Neural oscillations, or brainwaves, are rhythmic or repetitive patterns of neural activity in the central nervous system. Neural tissue can generate oscillatory activity in many ways, driven either by mechanisms within individual neurons or by interactions between neurons.  In individual neurons, oscillations can appear either as oscillations in membrane potential or as rhythmic patterns of action potentials, which then produce oscillatory activation of post-synaptic neurons.  At the level of neural ensembles, synchronized activity of large numbers of neurons can give rise to macroscopic oscillations, which can be observed in an electroencephalogram. Oscillatory activity in groups of neurons generally arises from feedback connections between the neurons that result in the synchronization of their firing patterns. The interaction between neurons can give rise to oscillations at a different frequency than the firing frequency of individual neurons. A well-known example of macroscopic neural oscillations is alpha activity.

Neural oscillations in humans were observed by researchers as early as 1924 (by Hans Berger). More than 50 years later, intrinsic oscillatory behavior was encountered in vertebrate neurons, but its functional role is still not fully understood. The possible roles of neural oscillations include feature binding, information transfer mechanisms and the generation of rhythmic motor output. Over the last decades more insight has been gained, especially with advances in brain imaging. A major area of research in neuroscience involves determining how oscillations are generated and what their roles are. Oscillatory activity in the brain is widely observed at different levels of organization and is thought to play a key role in processing neural information. Numerous experimental studies support a functional role of neural oscillations; a unified interpretation, however, is still lacking.

History

Richard Caton discovered electrical activity in the cerebral hemispheres of rabbits and monkeys and presented his findings in 1875. Adolf Beck published in 1890 his observations of spontaneous electrical activity of the brain of rabbits and dogs that included rhythmic oscillations altered by light detected with electrodes directly placed on the surface of the brain. Before Hans Berger, Vladimir Vladimirovich Pravdich-Neminsky published the first animal EEG and the evoked potential of a dog.

Overview

Neural oscillations are observed throughout the central nervous system at all levels, and include spike trains, local field potentials and large-scale oscillations which can be measured by electroencephalography (EEG). In general, oscillations can be characterized by their frequency, amplitude and phase. These signal properties can be extracted from neural recordings using time-frequency analysis. In large-scale oscillations, amplitude changes are considered to result from changes in synchronization within a neural ensemble, also referred to as local synchronization. In addition to local synchronization, oscillatory activity of distant neural structures (single neurons or neural ensembles) can synchronize. Neural oscillations and synchronization have been linked to many cognitive functions such as information transfer, perception, motor control and memory. Contrary to neuron synchronization, neural isolation is when electrical activity of neurons are not temporally synchronized. This is when the likelihood of the neuron to reach their threshold potential for the signal to propagate to the next neuron, decreases. This phenomenon is typically observed as the spectral intensity decreases from the summation of these neurons firing, which can be utilized to differentiate cognitive function or neural isolation. However new non-linear methods have be used that couple temporal and spectral entropic relationships simultaneously to characterize how neurons are isolated, (the signal's inability to propagate to adjacent neurons), an indicator of impairment (e.g., hypoxia).

Neural oscillations have been most widely studied in neural activity generated by large groups of neurons. Large-scale activity can be measured by techniques such as EEG. In general, EEG signals have a broad spectral content similar to pink noise, but also reveal oscillatory activity in specific frequency bands. The first discovered and best-known frequency band is alpha activity (8–12 Hz) that can be detected from the occipital lobe during relaxed wakefulness and which increases when the eyes are closed. Other frequency bands are: delta (1–4 Hz), theta (4–8 Hz), beta (13–30 Hz), low gamma (30–70 Hz), and high gamma (70–150 Hz) frequency bands, where faster rhythms such as gamma activity have been linked to cognitive processing. Indeed, EEG signals change dramatically during sleep and show a transition from faster frequencies to increasingly slower frequencies such as alpha waves. In fact, different sleep stages are commonly characterized by their spectral content. Consequently, neural oscillations have been linked to cognitive states, such as awareness and consciousness.

Although neural oscillations in human brain activity are mostly investigated using EEG recordings, they are also observed using more invasive recording techniques such as single-unit recordings. Neurons can generate rhythmic patterns of action potentials or spikes. Some types of neurons have the tendency to fire at particular frequencies, either as resonators or as intrinsic oscillators. Bursting is another form of rhythmic spiking. Spiking patterns are considered fundamental for information coding in the brain. Oscillatory activity can also be observed in the form of subthreshold membrane potential oscillations (i.e. in the absence of action potentials). If numerous neurons spike in synchrony, they can give rise to oscillations in local field potentials. Quantitative models can estimate the strength of neural oscillations in recorded data.

Neural oscillations are commonly studied from a mathematical framework and belong to the field of "neurodynamics", an area of research in the cognitive sciences that places a strong focus upon the dynamic character of neural activity in describing brain function. It considers the brain a dynamical system and uses differential equations to describe how neural activity evolves over time. In particular, it aims to relate dynamic patterns of brain activity to cognitive functions such as perception and memory. In very abstract form, neural oscillations can be analyzed analytically. When studied in a more physiologically realistic setting, oscillatory activity is generally studied using computer simulations of a computational model.

The functions of neural oscillations are wide-ranging and vary for different types of oscillatory activity. Examples are the generation of rhythmic activity such as a heartbeat and the neural binding of sensory features in perception, such as the shape and color of an object. Neural oscillations also play an important role in many neurological disorders, such as excessive synchronization during seizure activity in epilepsy or tremor in patients with Parkinson's disease. Oscillatory activity can also be used to control external devices such as a brain–computer interface.

Physiology

Oscillatory activity is observed throughout the central nervous system at all levels of organization. Three different levels have been widely recognized: the micro-scale (activity of a single neuron), the meso-scale (activity of a local group of neurons) and the macro-scale (activity of different brain regions).

Microscopic

Neurons generate action potentials resulting from changes in the electric membrane potential. Neurons can generate multiple action potentials in sequence forming so-called spike trains. These spike trains are the basis for neural coding and information transfer in the brain. Spike trains can form all kinds of patterns, such as rhythmic spiking and bursting, and often display oscillatory activity. Oscillatory activity in single neurons can also be observed in sub-threshold fluctuations in membrane potential. These rhythmic changes in membrane potential do not reach the critical threshold and therefore do not result in an action potential. They can result from postsynaptic potentials from synchronous inputs or from intrinsic properties of neurons.

Neuronal spiking can be classified by their activity patterns. The excitability of neurons can be subdivided in Class I and II. Class I neurons can generate action potentials with arbitrarily low frequency depending on the input strength, whereas Class II neurons generate action potentials in a certain frequency band, which is relatively insensitive to changes in input strength. Class II neurons are also more prone to display sub-threshold oscillations in membrane potential.

Mesoscopic

A group of neurons can also generate oscillatory activity. Through synaptic interactions, the firing patterns of different neurons may become synchronized and the rhythmic changes in electric potential caused by their action potentials will add up (constructive interference). That is, synchronized firing patterns result in synchronized input into other cortical areas, which gives rise to large-amplitude oscillations of the local field potential. These large-scale oscillations can also be measured outside the scalp using electroencephalography (EEG) and magnetoencephalography (MEG). The electric potentials generated by single neurons are far too small to be picked up outside the scalp, and EEG or MEG activity always reflects the summation of the synchronous activity of thousands or millions of neurons that have similar spatial orientation. Neurons in a neural ensemble rarely all fire at exactly the same moment, i.e. fully synchronized. Instead, the probability of firing is rhythmically modulated such that neurons are more likely to fire at the same time, which gives rise to oscillations in their mean activity (see figure at top of page). As such, the frequency of large-scale oscillations does not need to match the firing pattern of individual neurons. Isolated cortical neurons fire regularly under certain conditions, but in the intact brain cortical cells are bombarded by highly fluctuating synaptic inputs and typically fire seemingly at random. However, if the probability of a large group of neurons is rhythmically modulated at a common frequency, they will generate oscillations in the mean field (see also figure at top of page). Neural ensembles can generate oscillatory activity endogenously through local interactions between excitatory and inhibitory neurons. In particular, inhibitory interneurons play an important role in producing neural ensemble synchrony by generating a narrow window for effective excitation and rhythmically modulating the firing rate of excitatory neurons.

Macroscopic

Neural oscillation can also arise from interactions between different brain areas coupled through the structural connectome. Time delays play an important role here. Because all brain areas are bidirectionally coupled, these connections between brain areas form feedback loops. Positive feedback loops tend to cause oscillatory activity where frequency is inversely related to the delay time. An example of such a feedback loop is the connections between the thalamus and cortex – the thalamocortical radiations. This thalamocortical network is able to generate oscillatory activity known as recurrent thalamo-cortical resonance. The thalamocortical network plays an important role in the generation of alpha activity. In a whole-brain network model with realistic anatomical connectivity and propagation delays between brain areas, oscillations in the beta frequency range emerge from the partial synchronisation of subsets of brain areas oscillating in the gamma-band (generated at the mesoscopic level).

Mechanisms

Neuronal properties

Scientists have identified some intrinsic neuronal properties that play an important role in generating membrane potential oscillations. In particular, voltage-gated ion channels are critical in the generation of action potentials. The dynamics of these ion channels have been captured in the well-established Hodgkin–Huxley model that describes how action potentials are initiated and propagated by means of a set of differential equations. Using bifurcation analysis, different oscillatory varieties of these neuronal models can be determined, allowing for the classification of types of neuronal responses. The oscillatory dynamics of neuronal spiking as identified in the Hodgkin–Huxley model closely agree with empirical findings. In addition to periodic spiking, subthreshold membrane potential oscillations, i.e. resonance behavior that does not result in action potentials, may also contribute to oscillatory activity by facilitating synchronous activity of neighboring neurons. Like pacemaker neurons in central pattern generators, subtypes of cortical cells fire bursts of spikes (brief clusters of spikes) rhythmically at preferred frequencies. Bursting neurons have the potential to serve as pacemakers for synchronous network oscillations, and bursts of spikes may underlie or enhance neuronal resonance.

Network properties

Apart from intrinsic properties of neurons, biological neural network properties are also an important source of oscillatory activity. Neurons communicate with one another via synapses and affect the timing of spike trains in the post-synaptic neurons. Depending on the properties of the connection, such as the coupling strength, time delay and whether coupling is excitatory or inhibitory, the spike trains of the interacting neurons may become synchronized.  Neurons are locally connected, forming small clusters that are called neural ensembles. Certain network structures promote oscillatory activity at specific frequencies. For example, neuronal activity generated by two populations of interconnected inhibitory and excitatory cells can show spontaneous oscillations that are described by the Wilson-Cowan model.

If a group of neurons engages in synchronized oscillatory activity, the neural ensemble can be mathematically represented as a single oscillator. Different neural ensembles are coupled through long-range connections and form a network of weakly coupled oscillators at the next spatial scale. Weakly coupled oscillators can generate a range of dynamics including oscillatory activity. Long-range connections between different brain structures, such as the thalamus and the cortex (see thalamocortical oscillation), involve time-delays due to the finite conduction velocity of axons. Because most connections are reciprocal, they form feed-back loops that support oscillatory activity. Oscillations recorded from multiple cortical areas can become synchronized to form large-scale brain networks, whose dynamics and functional connectivity can be studied by means of spectral analysis and Granger causality measures. Coherent activity of large-scale brain activity may form dynamic links between brain areas required for the integration of distributed information.

Neuromodulation

In addition to fast direct synaptic interactions between neurons forming a network, oscillatory activity is regulated by neuromodulators on a much slower time scale. That is, the concentration levels of certain neurotransmitters are known to regulate the amount of oscillatory activity. For instance, GABA concentration has been shown to be positively correlated with frequency of oscillations in induced stimuli. A number of nuclei in the brainstem have diffuse projections throughout the brain influencing concentration levels of neurotransmitters such as norepinephrine, acetylcholine and serotonin. These neurotransmitter systems affect the physiological state, e.g., wakefulness or arousal, and have a pronounced effect on amplitude of different brain waves, such as alpha activity.

Mathematical description

Oscillations can often be described and analyzed using mathematics. Mathematicians have identified several dynamical mechanisms that generate rhythmicity.  Among the most important are harmonic (linear) oscillators, limit cycle oscillators, and delayed-feedback oscillators.  Harmonic oscillations appear very frequently in nature—examples are sound waves, the motion of a pendulum, and vibrations of every sort. They generally arise when a physical system is perturbed by a small degree from a minimum-energy state, and are well understood mathematically.  Noise-driven harmonic oscillators realistically simulate alpha rhythm in the waking EEG as well as slow waves and spindles in the sleep EEG. Successful EEG analysis algorithms were based on such models. Several other EEG components are better described by limit-cycle or delayed-feedback oscillations.  Limit-cycle oscillations arise from physical systems that show large deviations from equilibrium, whereas delayed-feedback oscillations arise when components of a system affect each other after significant time delays.  Limit-cycle oscillations can be complex but there are powerful mathematical tools for analyzing them; the mathematics of delayed-feedback oscillations is primitive in comparison. Linear oscillators and limit-cycle oscillators qualitatively differ in terms of how they respond to fluctuations in input.  In a linear oscillator, the frequency is more or less constant but the amplitude can vary greatly. In a limit-cycle oscillator, the amplitude tends to be more or less constant but the frequency can vary greatly.  A heartbeat is an example of a limit-cycle oscillation in that the frequency of beats varies widely, while each individual beat continues to pump about the same amount of blood.

Computational models adopt a variety of abstractions in order to describe complex oscillatory dynamics observed in brain activity. Many models are used in the field, each defined at a different level of abstraction and trying to model different aspects of neural systems. They range from models of the short-term behaviour of individual neurons, through models of how the dynamics of neural circuitry arise from interactions between individual neurons, to models of how behaviour can arise from abstract neural modules that represent complete subsystems.

Single neuron model

A model of a biological neuron is a mathematical description of the properties of nerve cells, or neurons, that is designed to accurately describe and predict its biological processes. One of the most successful neuron models is the Hodgkin–Huxley model, for which Hodgkin and Huxley won the 1963 Nobel Prize in physiology or medicine. The model is based on data from the squid giant axon and consists of nonlinear differential equations that approximate the electrical characteristics of a neuron, including the generation and propagation of action potentials. The model is so successful at describing these characteristics that variations of its "conductance-based" formulation continue to be utilized in neuron models over a half a century later.

The Hodgkin–Huxley model is too complicated to understand using classical mathematical techniques, so researchers often turn to simplifications such as the FitzHugh–Nagumo model and the Hindmarsh–Rose model, or highly idealized neuron models such as the leaky integrate-and-fire neuron, originally developed by Lapique in 1907. Such models only capture salient membrane dynamics such as spiking or bursting at the cost of biophysical detail, but are more computationally efficient, enabling simulations of larger biological neural networks.

Spiking model

A neural network model describes a population of physically interconnected neurons or a group of disparate neurons whose inputs or signalling targets define a recognizable circuit.  These models aim to describe how the dynamics of neural circuitry arise from interactions between individual neurons. Local interactions between neurons can result in the synchronization of spiking activity and form the basis of oscillatory activity. In particular, models of interacting pyramidal cells and inhibitory interneurons have been shown to generate brain rhythms such as gamma activity. Similarly, it was shown that simulations of neural networks with a phenomenological model for neuronal response failures can predict spontaneous broadband neural oscillations.

Neural mass model

Neural field models are another important tool in studying neural oscillations and are a mathematical framework describing evolution of variables such as mean firing rate in space and time. In modeling the activity of large numbers of neurons, the central idea is to take the density of neurons to the continuum limit, resulting in spatially continuous neural networks. Instead of modelling individual neurons, this approach approximates a group of neurons by its average properties and interactions. It is based on the mean field approach, an area of statistical physics that deals with large-scale systems. Models based on these principles have been used to provide mathematical descriptions of neural oscillations and EEG rhythms. They have for instance been used to investigate visual hallucinations.

Kuramoto model

The Kuramoto model of coupled phase oscillators is one of the most abstract and fundamental models used to investigate neural oscillations and synchronization. It captures the activity of a local system (e.g., a single neuron or neural ensemble) by its circular phase alone and hence ignores the amplitude of oscillations (amplitude is constant). Interactions amongst these oscillators are introduced by a simple algebraic form (such as a sine function) and collectively generate a dynamical pattern at the global scale. The Kuramoto model is widely used to study oscillatory brain activity and several extensions have been proposed that increase its neurobiological plausibility, for instance by incorporating topological properties of local cortical connectivity. In particular, it describes how the activity of a group of interacting neurons can become synchronized and generate large-scale oscillations. Simulations using the Kuramoto model with realistic long-range cortical connectivity and time-delayed interactions reveal the emergence of slow patterned fluctuations that reproduce resting-state BOLD functional maps, which can be measured using fMRI.

Activity patterns

Both single neurons and groups of neurons can generate oscillatory activity spontaneously. In addition, they may show oscillatory responses to perceptual input or motor output. Some types of neurons will fire rhythmically in the absence of any synaptic input. Likewise, brain-wide activity reveals oscillatory activity while subjects do not engage in any activity, so-called resting-state activity. These ongoing rhythms can change in different ways in response to perceptual input or motor output. Oscillatory activity may respond by increases or decreases in frequency and amplitude or show a temporary interruption, which is referred to as phase resetting. In addition, external activity may not interact with ongoing activity at all, resulting in an additive response.

Ongoing activity

Spontaneous activity is brain activity in the absence of an explicit task, such as sensory input or motor output, and hence also referred to as resting-state activity. It is opposed to induced activity, i.e. brain activity that is induced by sensory stimuli or motor responses.  The term ongoing brain activity is used in electroencephalography and magnetoencephalography for those signal components that are not associated with the processing of a stimulus or the occurrence of specific other events, such as moving a body part, i.e. events that do not form evoked potentials/evoked fields, or induced activity. Spontaneous activity is usually considered to be noise if one is interested in stimulus processing; however, spontaneous activity is considered to play a crucial role during brain development, such as in network formation and synaptogenesis.  Spontaneous activity may be informative regarding the current mental state of the person (e.g. wakefulness, alertness) and is often used in sleep research. Certain types of oscillatory activity, such as alpha waves, are part of spontaneous activity. Statistical analysis of power fluctuations of alpha activity reveals a bimodal distribution, i.e. a high- and low-amplitude mode, and hence shows that resting-state activity does not just reflect a noise process. In case of fMRI, spontaneous fluctuations in the blood-oxygen-level dependent (BOLD) signal reveal correlation patterns that are linked to resting states networks, such as the default network. The temporal evolution of resting state networks is correlated with fluctuations of oscillatory EEG activity in different frequency bands.

Ongoing brain activity may also have an important role in perception, as it may interact with activity related to incoming stimuli. Indeed, EEG studies suggest that visual perception is dependent on both the phase and amplitude of cortical oscillations. For instance, the amplitude and phase of alpha activity at the moment of visual stimulation predicts whether a weak stimulus will be perceived by the subject.

Frequency response

In response to input, a neuron or neuronal ensemble may change the frequency at which it oscillates, thus changing the rate at which it spikes. Often, a neuron's firing rate depends on the summed activity it receives. Frequency changes are also commonly observed in central pattern generators and directly relate to the speed of motor activities, such as step frequency in walking. However, changes in relative oscillation frequency between different brain areas is not so common because the frequency of oscillatory activity is often related to the time delays between brain areas.

Amplitude response

Next to evoked activity, neural activity related to stimulus processing may result in induced activity. Induced activity refers to modulation in ongoing brain activity induced by processing of stimuli or movement preparation. Hence, they reflect an indirect response in contrast to evoked responses. A well-studied type of induced activity is amplitude change in oscillatory activity. For instance, gamma activity often increases during increased mental activity such as during object representation. Because induced responses may have different phases across measurements and therefore would cancel out during averaging, they can only be obtained using time-frequency analysis. Induced activity generally reflects the activity of numerous neurons: amplitude changes in oscillatory activity are thought to arise from the synchronization of neural activity, for instance by synchronization of spike timing or membrane potential fluctuations of individual neurons. Increases in oscillatory activity are therefore often referred to as event-related synchronization, while decreases are referred to as event-related desynchronization.

Phase resetting

Phase resetting occurs when input to a neuron or neuronal ensemble resets the phase of ongoing oscillations. It is very common in single neurons where spike timing is adjusted to neuronal input (a neuron may spike at a fixed delay in response to periodic input, which is referred to as phase locking) and may also occur in neuronal ensembles when the phases of their neurons are adjusted simultaneously. Phase resetting is fundamental for the synchronization of different neurons or different brain regions because the timing of spikes can become phase locked to the activity of other neurons.

Phase resetting also permits the study of evoked activity, a term used in electroencephalography and magnetoencephalography for responses in brain activity that are directly related to stimulus-related activity. Evoked potentials and event-related potentials are obtained from an electroencephalogram by stimulus-locked averaging, i.e. averaging different trials at fixed latencies around the presentation of a stimulus. As a consequence, those signal components that are the same in each single measurement are conserved and all others, i.e. ongoing or spontaneous activity, are averaged out. That is, event-related potentials only reflect oscillations in brain activity that are phase-locked to the stimulus or event. Evoked activity is often considered to be independent from ongoing brain activity, although this is an ongoing debate.

Asymmetric amplitude modulation

It has recently been proposed that even if phases are not aligned across trials, induced activity may still cause event-related potentials because ongoing brain oscillations may not be symmetric and thus amplitude modulations may result in a baseline shift that does not average out. This model implies that slow event-related responses, such as asymmetric alpha activity, could result from asymmetric brain oscillation amplitude modulations, such as an asymmetry of the intracellular currents that propagate forward and backward down the dendrites. Under this assumption, asymmetries in the dendritic current would cause asymmetries in oscillatory activity measured by EEG and MEG, since dendritic currents in pyramidal cells are generally thought to generate EEG and MEG signals that can be measured at the scalp.

Cross-frequency coupling
Cross-frequency coupling (CFC) describes the coupling (statistical correlation) between a slow wave and a fast wave. There are many kinds, generally written as A-B coupling, meaning the A of a slow wave is coupled with the B of a fast wave. For example, phase–amplitude coupling is where the phase of a slow wave is coupled with the amplitude of a fast wave.

The theta-gamma code is a coupling between theta wave and gamma wave in the hippocampal network. During a theta wave, 4 to 8 non-overlapping neuron ensembles are activated in sequence. This has been hypothesized to form a neural code representing multiple items in a temporal frame

Function

Neural synchronization can be modulated by task constraints, such as attention, and is thought to play a role in feature binding, neuronal communication, and motor coordination. Neuronal oscillations became a hot topic in neuroscience in the 1990s when the studies of the visual system of the brain by Gray, Singer and others appeared to support the neural binding hypothesis. According to this idea, synchronous oscillations in neuronal ensembles bind neurons representing different features of an object. For example, when a person looks at a tree, visual cortex neurons representing the tree trunk and those representing the branches of the same tree would oscillate in synchrony to form a single representation of the tree. This phenomenon is best seen in local field potentials which reflect the synchronous activity of local groups of neurons, but has also been shown in EEG and MEG recordings providing increasing evidence for a close relation between synchronous oscillatory activity and a variety of cognitive functions such as perceptual grouping and attentional top-down control.

Pacemaker

Cells in the sinoatrial node, located in the right atrium of the heart, spontaneously depolarize approximately 100 times per minute. Although all of the heart's cells have the ability to generate action potentials that trigger cardiac contraction, the sinoatrial node normally initiates it, simply because it generates impulses slightly faster than the other areas. Hence, these cells generate the normal sinus rhythm and are called pacemaker cells as they directly control the heart rate. In the absence of extrinsic neural and hormonal control, cells in the SA node will rhythmically discharge. The sinoatrial node is richly innervated by the autonomic nervous system, which up or down regulates the spontaneous firing frequency of the pacemaker cells.

Central pattern generator

Synchronized firing of neurons also forms the basis of periodic motor commands for rhythmic movements. These rhythmic outputs are produced by a group of interacting neurons that form a network, called a central pattern generator. Central pattern generators are neuronal circuits that—when activated—can produce rhythmic motor patterns in the absence of sensory or descending inputs that carry specific timing information. Examples are walking, breathing, and swimming, Most evidence for central pattern generators comes from lower animals, such as the lamprey, but there is also evidence for spinal central pattern generators in humans.

Information processing

Neuronal spiking is generally considered the basis for information transfer in the brain. For such a transfer, information needs to be coded in a spiking pattern. Different types of coding schemes have been proposed, such as rate coding and temporal coding. Neural oscillations could create periodic time windows in which input spikes have larger effect on neurons, thereby providing a mechanism for decoding temporal codes.

Temporal decoding

Single-cell intrinsic oscillators serve as valuable tools for decoding temporally-encoded sensory information. This information is encoded through inter-spike intervals, and intrinsic oscillators can act as 'temporal rulers' for precisely measuring these intervals. One notable mechanism for achieving this is the neuronal phase-locked loop (NPLL). In this mechanism, cortical oscillators undergo modulation influenced by the firing rates of thalamocortical 'phase detectors,' which, in turn, gauge the disparity between the cortical and sensory periodicity.

Perception

Synchronization of neuronal firing may serve as a means to group spatially segregated neurons that respond to the same stimulus in order to bind these responses for further joint processing, i.e. to exploit temporal synchrony to encode relations. Purely theoretical formulations of the binding-by-synchrony hypothesis were proposed first, but subsequently extensive experimental evidence has been reported supporting the potential role of synchrony as a relational code.

The functional role of synchronized oscillatory activity in the brain was mainly established in experiments performed on awake kittens with multiple electrodes implanted in the visual cortex. These experiments showed that groups of spatially segregated neurons engage in synchronous oscillatory activity when activated by visual stimuli. The frequency of these oscillations was in the range of 40 Hz and differed from the periodic activation induced by the grating, suggesting that the oscillations and their synchronization were due to internal neuronal interactions. Similar findings were shown in parallel by the group of Eckhorn, providing further evidence for the functional role of neural synchronization in feature binding. Since then, numerous studies have replicated these findings and extended them to different modalities such as EEG, providing extensive evidence of the functional role of gamma oscillations in visual perception.

Gilles Laurent and colleagues showed that oscillatory synchronization has an important functional role in odor perception. Perceiving different odors leads to different subsets of neurons firing on different sets of oscillatory cycles.  These oscillations can be disrupted by GABA blocker picrotoxin, and the disruption of the oscillatory synchronization leads to impairment of behavioral discrimination of chemically similar odorants in bees and to more similar responses across odors in downstream β-lobe neurons. Recent follow-up of this work has shown that oscillations create periodic integration windows for Kenyon cells in the insect mushroom body, such that incoming spikes from the antennal lobe are more effective in activating Kenyon cells only at specific phases of the oscillatory cycle.

Neural oscillations are also thought be involved in the sense of time and in somatosensory perception. However, recent findings argue against a clock-like function of cortical gamma oscillations.

Motor coordination

Oscillations have been commonly reported in the motor system. Pfurtscheller and colleagues found a reduction in alpha (8–12 Hz) and beta (13–30 Hz) oscillations in EEG activity when subjects made a movement. Using intra-cortical recordings, similar changes in oscillatory activity were found in the motor cortex when the monkeys performed motor acts that required significant attention. In addition, oscillations at spinal level become synchronised to beta oscillations in the motor cortex during constant muscle activation, as determined by cortico-muscular coherence. Likewise, muscle activity of different muscles reveals inter-muscular coherence at multiple distinct frequencies reflecting the underlying neural circuitry involved in motor coordination.

Recently it was found that cortical oscillations propagate as travelling waves across the surface of the motor cortex along dominant spatial axes characteristic of the local circuitry of the motor cortex. It has been proposed that motor commands in the form of travelling waves can be spatially filtered by the descending fibres to selectively control muscle force. Simulations have shown that ongoing wave activity in cortex can elicit steady muscle force with physiological levels of EEG-EMG coherence.

Oscillatory rhythms at 10 Hz have been recorded in a brain area called the inferior olive, which is associated with the cerebellum. These oscillations are also observed in motor output of physiological tremor and when performing slow finger movements. These findings may indicate that the human brain controls continuous movements intermittently. In support, it was shown that these movement discontinuities are directly correlated to oscillatory activity in a cerebello-thalamo-cortical loop, which may represent a neural mechanism for the intermittent motor control.

Memory

Neural oscillations, in particular theta activity, are extensively linked to memory function. Theta rhythms are very strong in rodent hippocampi and entorhinal cortex during learning and memory retrieval, and they are believed to be vital to the induction of long-term potentiation, a potential cellular mechanism for learning and memory. Coupling between theta and gamma activity is thought to be vital for memory functions, including episodic memory. Tight coordination of single-neuron spikes with local theta oscillations is linked to successful memory formation in humans, as more stereotyped spiking predicts better memory.

Sleep and consciousness

Sleep is a naturally recurring state characterized by reduced or absent consciousness and proceeds in cycles of rapid eye movement (REM) and non-rapid eye movement (NREM) sleep. Sleep stages are characterized by spectral content of EEG: for instance, stage N1 refers to the transition of the brain from alpha waves (common in the awake state) to theta waves, whereas stage N3 (deep or slow-wave sleep) is characterized by the presence of delta waves. The normal order of sleep stages is N1 → N2 → N3 → N2 → REM.

Development

Neural oscillations may play a role in neural development. For example, retinal waves are thought to have properties that define early connectivity of circuits and synapses between cells in the retina.

Pathology

Specific types of neural oscillations may also appear in pathological situations, such as Parkinson's disease or epilepsy. These pathological oscillations often consist of an aberrant version of a normal oscillation. For example, one of the best known types is the spike and wave oscillation, which is typical of generalized or absence epileptic seizures, and which resembles normal sleep spindle oscillations.

Tremor

A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving to-and-fro movements of one or more body parts. It is the most common of all involuntary movements and can affect the hands, arms, eyes, face, head, vocal cords, trunk, and legs. Most tremors occur in the hands. In some people, tremor is a symptom of another neurological disorder. Many different forms of tremor have been identified, such as essential tremor or Parkinsonian tremor. It is argued that tremors are likely to be multifactorial in origin, with contributions from neural oscillations in the central nervous systems, but also from peripheral mechanisms such as reflex loop resonances.

Epilepsy

Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.

Thalamocortical dysrhythmia

In thalamocortical dysrhythmia (TCD), normal thalamocortical resonance is disrupted. The thalamic loss of input allows the frequency of the thalamo-cortical column to slow into the theta or delta band as identified by MEG and EEG by machine learning. TCD can be treated with neurosurgical methods like thalamotomy.

Applications

Clinical endpoints
Neural oscillations are sensitive to several drugs influencing brain activity; accordingly, biomarkers based on neural oscillations are emerging as secondary endpoints in clinical trials and in quantifying effects in pre-clinical studies. These biomarkers are often named "EEG biomarkers" or "Neurophysiological Biomarkers" and are quantified using quantitative electroencephalography (qEEG). EEG biomarkers can be extracted from the EEG using the open-source Neurophysiological Biomarker Toolbox.

Brain–computer interface

Neural oscillation has been applied as a control signal in various brain–computer interfaces (BCIs). For example, a non-invasive BCI  can be created by placing electrodes on the scalp and then measuring the weak electric signals. Although individual neuron activities cannot be recorded through non-invasive BCI because the skull damps and blurs the electromagnetic signals, oscillatory activity can still be reliably detected. The BCI was introduced by Vidal in 1973 as challenge of using EEG signals to control objects outside human body.

After the BCI challenge, in 1988, alpha rhythm was used in a brain rhythm based BCI for control of a physical object, a robot. Alpha rhythm based BCI was the first BCI for control of a robot. In particular, some forms of BCI allow users to control a device by measuring the amplitude of oscillatory activity in specific frequency bands, including mu and beta rhythms.

Examples
A non-inclusive list of types of oscillatory activity found in the central nervous system:

 Alpha wave
 Beta wave
 Bursting
 Cardiac cycle
 Delta wave
 Epileptic seizure
 Gamma wave
 Mathematical modeling of electrophysiological activity in epilepsy
 Mu wave
 PGO waves
 Thalamocortical oscillations
 Sharp wave–ripple complexes
 Sleep spindle
 Subthreshold membrane potential oscillations
 Theta wave

See also
 Cybernetics
 Dynamical systems theory
 EEG analysis
 Neurocybernetics
 Oscillatory neural network
 Systems neuroscience
 ThetaHealing
 Phase resetting in neurons

References

Further reading

External links
 Binding by synchronization
 Neural Field Theory
 Spike-and-wave oscillations
 Synchronization
 Bursting

Articles containing video clips
Computational neuroscience
Electrophysiology
Neural circuits
Neural coding
Neurophysiology
Neuroscience

Neural oscillation


Mailoc or Maeloc was a 6th-century bishop of Britonia, a settlement founded by expatriate Britons in Galicia, Spain. He represented his diocese, referred to as the Britonensis ecclesia or "Britonnic church", at the Second Council of Braga in 572. Records of the council refer to his see, the sedes Britonarum ("See of the Britons"), which may have been seated at the monastery of Saint Mary of Britonia. Mailoc's name is clearly Brythonic, deriving from the Celtic *Maglācos, thereby providing further evidence for the Britonnic presence in the area, but he is the only one to have a Celtic name.

See also
 Diocese of Ferrol-Mondoñedo (Formerly known as: Dioecesis Britoniensis).

Notes

References
Koch, John T. (2006). Celtic Culture: A Historical Encyclopedia. Santa Barbara: ABC-CLIO.
Richards, Melville, "Mailoc", Habis, III, 1972, p. 159.
Tovar, António, "Un obispo con nombre británico y los orígenes de la diócesis de Mondoñedo", Habis, III, 1972, pp. 155–158.
Vives, J., Concilios visigóticos e hispano-romanos, Madrid, 1963.
Young, Simon, The Bishops of the early medieval diocese of Britonia (forthcoming).
Young, Simon, "Note on Britones in Thirteenth-century Galicia", Studia Celtica, XXXV (2001), pp. 361–2.
Young, Simon, "The Forgotten Colony", History Today, L, oct. 2000, pp. 5–6.

External links
  The Mindoniensis-Ferrolensis Province in the 21st Century (Alternatives: The Britonia Province)

6th-century Galician bishops
Sub-Roman Britons
6th-century English people

Mailoc


Kito Lorenc (4 March 1938 – 24 September 2017) was a Sorbian-German writer, lyric poet and translator. He was a grandson of the Sorbian writer and politician Jakub Lorenc-Zalěski. He was born in Schleife, Germany.

Lorenc was an employee at the Institute for Sorbian People Research in Bautzen between 1961 and 1972.  From 1972 until 1979, he worked as a dramaturge at the State Ensemble for Sorbian People's Culture.  Kito Lorenc was a member of the Sächsischen Akademie der Künste and lived as a freelance writer in Wuischke by Hochkirch.

Lorenc died in Bautzen, Germany on 24 September 2017 of a stroke at the age of 79.

References

1938 births
2017 deaths
German historians
German poets
Writers from Brandenburg

Kito Lorenc


The eastern mosquitofish, eastern gambusia,  or mosquito fish (Gambusia holbrooki) is a fish that belongs to the Poeciliidae family.  It is from the eastern United States but human beings brought it to many other parts of the world, such as Hawaii, Puerto Rico, and Australia, where it has caused problems as an invasive species.

The adult male eastern mosquitofish grows to 3.5 cm and the female to 6.0 cm.  It is green or brown on top and blue, white or silver on the bottom.  It has large eyes and one dorsal fin and a round tail fin.

This fish likes to live in fresh water but can live in water that has some salt.  It can survive cold and warm temperatures.  It eats insects and their larvae.

People brought the eastern mosquitofish to Hawaii in the 1910s and to Australia in the 1920s and set it free there.  They thought it would eat mosquito larvae so there would be fewer mosquitoes.  But the eastern mosquitofish did not eat more mosquitoes than the fish that were already in Australia did.  The eastern mosquitofish outcompetes other fish and bites their tails or even eats them.  It can kill larger fish by damaging their fins.  In the western United States, the eastern mosquitofish killed or outcompeted many other fish that were better at controlling mosquitoes than it is.  After people put eastern mosquitofish in a body of water, there may be an algal bloom because the eastern mosquitofish eats or kills all the fish that usually eat the algae.

This fish likes to eat frog eggs and tadpoles.  It is one reason why the green and golden bell frog is endangered in Australia and the Chiricahua leopard frog in Arizona.

The fish has 50-300 eggs at a time.  The eggs stay inside the female's body until they hatch.  It takes the new fish two months to become adults.  Eastern mosquitofish can do this several times each year.

The western mosquitofish G. affinis and eastern mosquitofish G. holbrooki used to both be called G. affinis because people thought they were the same species.  They are not.  According to the IUCN Global Invasive Species Database, most records in Australia that say "G. affinis" really refer to G. holbrooki.

References

Freshwater fish
Cyprinodontiformes

Eastern mosquitofish


William Ernest Bowman (30 September 1911 in Scarborough – 1 January 1985) was an engineer and writer, best remembered for his 1956 book The Ascent of Rum Doodle, a satire on the world of mountaineering literature inspired by Bill Tilman and his 1937 account of the Nanda Devi expedition. Bowman's work was a send-up of the rather pompous British expedition book style fashionable in the 1930s through to the 1950s.

Bill Bowman was the eldest of a family of three boys. His mother died in 1926 when Bill was 15, and his father in 1928 from World War I exposure to mustard gas. This led to a separation of the three brothers - Bill to Middlesbrough, the middle brother, John Howard (Howie), to Canada and the youngest, Lawrence, sent to live with another family.

Bill left school when he was 16, subsequently following a career as draughtsman and civil engineer. During World War II he served in Egypt as a radar instructor for the Royal Air Force (RAF), and afterwards joined the International Voluntary Service for Peace in Duisburg, Germany. His pacifist convictions persuaded him to return his RAF paybook to the government.

The Cruise of the Talking Fish is Bowman's only other published work. It is a parody of the Kon-Tiki Expedition by Thor Heyerdahl. He did, however, write a number of pieces including a layman's interpretation of Relativity and several short stories.
Bowman's leisure activities included hillwalking and painting.

References

English satirists
British parodists
Parody novelists
1911 births
1985 deaths
People from Scarborough, North Yorkshire
20th-century English male writers

William Ernest Bowman


David C. O'Neal (January 24, 1937 – July 10, 2021) was an American politician who served as the 41st Lieutenant Governor of Illinois from 1977 to 1981. For six years he served as Saint Clair County Sheriff, the first Republican to hold that office in twenty years.

Background
O'Neal was born January 24, 1937, in Belleville, Illinois. He graduated from St. Louis College of Pharmacy and was a former ministerial student and United States Marine. Prior to entering politics O'Neal was a pharmacist and businessman. He served as a member of the executive and economic development committees of the National Conference of Lieutenant Governors and the governing boards of McKendree University in Lebanon, and the Saint Louis College of Pharmacy. He is the recipient of the Illinois Wisconsin States Association of Elks Humanitarian of the Year and East Saint Louis Model Cities Program Meritorious Services Award and was named Outstanding Young Republican of the United States in 1975 and Outstanding Young Republican of Illinois in 1971.

In 1977, he received the Distinguished Pharmacist Award from the Illinois Pharmacists' Association. An athlete, his hobbies include sports such as tennis, golf, bowling and motorcycling.

Lt. Governor of Illinois
Lieutenant Governor O'Neal devoted much effort to overseeing the Senior Legislative Forum, a legislative advocacy group he created to aid senior citizens throughout Illinois. He also worked closely with the State's two Senior Action Centers, which provides assistance with the elderly and disabled.

His other responsibilities have included chairmanships of the Governor's Special Commission on State-Mandated Programs, the Technical Advisory Committee on Aging, the Illinois Energy Contingency Council's Subcommittee, the Governor's Jail and Detention Standards Review Committee, and a committee to investigate administrative and correctional officer conditions at adult correctional centers.

He has also served as vice-chairman of the Governor's Energy Advisory Council, ex officio member of the Council on Aging, and a member of the Commission on Inter-Governmental Cooperation.

In 1980 O'Neal sought the Republican nomination for the U.S. Senate winning the nomination to go on to the general election. His Democratic opponent was Illinois Secretary of State Alan Dixon. After a tough election battle O'Neal went down to defeat; Dixon defeated O'Neal in a vote of 2,565,302–1,946,296. O'Neal resigned as Lieutenant Governor in 1981, claiming that he was just bored.

O'Neal served as Assistant Secretary of the Interior, Division of Energy and Natural Resources in George H.W. Bush administration.

He died on July 10, 2021, in Las Vegas, Nevada, at age 84.

References

1937 births
2021 deaths
Lieutenant Governors of Illinois
American pharmacists
United States Marines
Illinois Republicans
Illinois sheriffs
People from Belleville, Illinois
Businesspeople from Illinois
Military personnel from Illinois
University of Health Sciences and Pharmacy in St. Louis alumni

Dave O'Neal


Citrus australasica, the Australian finger lime or caviar lime, is a thorny understorey shrub or small tree of lowland subtropical rainforest and rainforest in the coastal border region of Queensland and New South Wales, Australia.

It has edible fruits which are under development as a commercially sold crop.

Description
The plant is  in height. The leaves are small,  long and  wide, glabrous, with a notched tip and crenate towards the apex. Flowers are white with petals  long. The fruit is cylindrical,  long, sometimes slightly curved, coming in different colours, including pink and green.

Cultivation and uses

History
Early settlers consumed the fruit and retained the trees when clearing for agriculture. Colonial botanists suggested that they should be cultivated, due to the lack of citrus alternatives.

Rising demand

The finger lime has been recently popularised as a gourmet bushfood. The globular juice vesicles (also known as pearls) have been likened to a "lime caviar", which can be used as a garnish or added to various recipes. The fresh vesicles have the effect of a burst of effervescent tangy flavour as they are chewed. The fruit juice is acidic and similar to that of a lime. Marmalade and pickles are also made from finger lime. Finger lime peel can be dried and used as a flavouring spice.

Commercial use of finger lime fruit started in the mid-1990s with boutique marmalades made from wild harvested fruit. By 2000 the finger lime was being sold in restaurants, and exported fresh.

The finger lime has been recently grown on a commercial basis in Australia in response to high demand for the fruit. There is an increasing range of genetic selections which are budded onto citrus rootstock. With the sudden high market demand for the fruit the primary source of genetic material for propagation has been selections from wild stock.

Diseases

In cultivation, the finger lime plant is grown in much the same way as other citrus species. It may be subject to some pests and diseases requiring pest control in cropping situations. This includes scale, caterpillars, gall-wasp, and limb dieback. Fruit fly research has concluded that finger limes are a non-host plant to fruit flies and as such are not a quarantine risk to importing countries.

Research conducted since the 1970s indicated that a wild selection of C. australasica was highly resistant to Phytophthora citrophthora root disease, which has resulted in a cross-breeding program with finger lime to develop disease-resistant citrus rootstock. In 2020, researchers began working with C. australasica to develop solutions for Citrus greening disease.

The CSIRO has also developed several Citrus hybrids by crossing the finger lime with standard Citrus species. These hybrids have created many cultivars  which generate finger limes in many different colors ranging from light pink to deep blue-green.  Finger lime is thought to have the widest range of color variation within any Citrus species.  The color of the pulp (juice vesicles) comes in shades of green or pink including pale lime-green, pale pink, coral, and scarlet.

Taxonomy
Historically the finger lime was viewed as a member of the genus Citrus. The Swingle system of taxonomy instead divided the historical true citrus into seven genera, placing the finger lime along with the round lime in a novel genus, Microcitrus. However, subsequent studies have favored a broader concept of Citrus that reunites the genera separated by Swingle, restoring the finger lime to Citrus.

References

External links

Australian Aboriginal bushcraft
Australian cuisine
Bushfood
australasica
Crops originating from Australia
Edible fruits
Flora of New South Wales
Flora of Queensland
australasica
Plants described in 1858
Sapindales of Australia
Taxa named by Ferdinand von Mueller

Citrus australasica


Albert Dubois-Pillet (28 October 1846 – 18 August 1890) was a French Neo-impressionist painter and a career army officer. He was instrumental in the founding of the Société des Artistes Indépendants, and was one of the first artists to embrace Pointillism.

Early life and military service

Louis-Auguste-Albert Dubois was born on 28 October 1846 in Paris. Shortly thereafter, his family moved to Toulouse, where he was raised. In 1867, he graduated from l'Ecole Impériale Militaire in Saint-Cyr and began his career as a military officer. He remained in the army for the rest of his life.

From 1870 to 1871, he served in the Franco-Prussian War, during which the Germans captured him and held him in Westphalia, Prussia as a prisoner of war. After his release, he resumed a post in the Versailles army. Throughout the 1870s he was stationed at several different provincial posts. He received an appointment in 1879 or 1880 to la Légion de la Garde Républicaine (the Republican Guard) in Paris.

Early art career

Although self-taught, with no formal art education, he proved to be a talented artist. The official Paris Salon accepted one of his still lifes in 1877, and another one in 1879. However, after his arrival in Paris, he created paintings which were somewhat more experimental, and his submissions were rejected by The Salons from 1880 to 1883.

Beginning in 1884, he attempted to hide his art-related activities from the military by disguising his name – he added "Pillet", his mother's maiden name, to his name, signing his artworks "Dubois-Pillet".

His painting Enfant Mort (Dead Child), completed in 1881, was displayed at the May 1884 Tuileries Exhibition, where it caught the attention of Émile Zola, who used it as his inspiration for a scene in his 1886 novel L'Œuvre. In the book, artist Claude Lantier, distraught over his son's death, finds himself compelled to create a painting of his dead child.

The Tuileries Exhibition was a one-time event with a goal similar to that of 1863's Salon des Refusés which showed works that had been rejected by the Salon. Dubois-Pillet envisioned a permanent alternative to the official Salon. He met with some of the other exhibitors, and he, Georges Seurat, Paul Signac, and Odilon Redon became the "founding fathers" of the Société des Artistes Indépendants. Dubois-Pillet structured the organization and, within less than a week, wrote and published its statutes, which are largely still in effect. The society was officially formed on 29 July 1884, and their first exhibition, which opened on 1 December 1884, included work by Dubois-Pillet. He used his connections to secure desirable venues and terms for their exhibitions, was the primary organizer of the group until 1888, and was a regular exhibitor with them until 1889.

Neo-impressionism

Around 1885, probably influenced by his friendships with Seurat and others, he began experimenting with Divisionist techniques, and he embraced Pointillism – one of the first artists to do so. By the next year, his works were fully Neo-impressionist. With Signac, he used pen and ink to create pointillist drawings. Dubois-Pillet's studio-apartment served as the unofficial Neo-impressionist headquarters during the movement's early years. Some of his pointillist work is composed with "photographic precision".

In 1886, he was ordered by the army to discontinue his participation in exhibiting his art, and to dissociate himself from Les Indépendants. Dubois-Pillet paid little attention to these orders. He remained active with Les Indépendants and continued to show his work, including regular Les Indépendants exhibits, an 1886 Nantes show, and participation in the 1888 and 1889 Les XX exhibitions in Brussels. His only solo exhibition during his lifetime was in 1888, at the offices of French symbolist journal Revue Indépendante. Some of his pointillist drawings were published in La Vie moderne in 1887.

Dubois-Pillet and Louis Hayet were the two Neo-impressionists who were most focused on the theoretical aspects and scientific basis of their art. Starting around 1887, Dubois-Pillet explored the science of color perception as it related to Pointillism by investigating the work of English polymath Thomas Young (1773–1829), who concluded that the eye has three color receptors, each sensitive to one of the primary colors of light (green, red, and violet). Dubois-Pillet applied Young's findings into a triad color theory which he referred to as passage, whereby a touch of pigment corresponding to each of the primary light colors is included in the passage from one hue to the next. Colors are scientifically decomposed by the artist, then they are recomposed in the viewer's eye, but with a greater luminosity than would have been possible if the colors had simply been mixed on the palette. How to apply his theory in practice wasn't entirely clear, and his fellow Neo-impressionists were not convinced.

Neo-impressionism was often focused on depicting brilliant colors in natural light, and perhaps because of this, the subject matter most commonly consisted of outdoor scenes such as landscapes, cityscapes, seascapes, or river scenes. While Dubois-Pillet painted all of these, as well as still lifes, he also created the first portrait of the Neo-impressionist movement – La Dame à la Robe Blanche, a painting which depicts a woman, wearing a white dress, seated in an upholstered chair. The model's identity is unknown; exhibition curators tended to, at best, identify subjects by the initial of their last name. The Musée d'Art Moderne de Saint-Etienne refers to her as Madame P., but art critic Félix Fénéon called her Mademoiselle B.

In late 1889, Dubois-Pillet was transferred by the army to a post as commander of the gendarmerie in Le Puy-en-Velay, a south central French commune. His transfer may have been in response to his defying the orders to curtail his artistic activities.

The churches and landscapes of the surrounding Auvergne region are the subject matter of his final paintings. He died in Le Puy-en-Velay on 18 August 1890 at the age of 43 during an outbreak of smallpox. The following year, a memorial exhibition, organized by Signac and consisting of sixty-four of Dubois-Pillet's paintings, was mounted by Les Indépendants. Because of a fire which destroyed the majority of his work, as well as his rather early death, his extant oeuvre is relatively small.

Collections
Indianapolis Museum of Art
J. Paul Getty Museum
Musée Crozatier
Musée d'Art Moderne, Saint-Étienne
Musée d'Orsay
Musée du Petit Palais, Geneva
The Phillips Collection

Gallery

References

Sources

Post-impressionist painters
Pointillism
19th-century French painters
French male painters
French military personnel of the Franco-Prussian War
French prisoners of war in the 19th century
Artists from Toulouse
1846 births
1890 deaths
Painters from Paris
Deaths from smallpox
19th-century French male artists

Albert Dubois-Pillet


Keith Lee Morris is an American author who has published three novels, The Greyhound God (University of Nevada Press, 2003), The Dart League King (Tin House Books, 2008) and Traveler's Rest (Little, Brown and Company, 2016) as well as two collections of short stories, The Best Seats in the House and Other Stories (University of Nevada Press, 2004) and Call It What You Want (Tin House Books, 2010). His work has been published in A Public Space, Tin House, The Southern Review, Ninth Letter, Story Quarterly, The New England Review, The Cincinnati Review, and The Georgia Review.

Morris received his MFA in Writing from the University of North Carolina at Greensboro.  He is currently an Associate Professor in creative writing in the Clemson University English Department.

Accolades
Morris's novel, The Dart League King, garnered a starred review and "Pick of the Week" in Publishers Weekly and a starred review from Booklist.

His story "Tired Heart" was included in the collection New Stories from the South: The Year's Best, 2006.

His story "The Culvert" won the 2005 Eudora Welty Prize

References

21st-century American novelists
American male novelists
Living people
Clemson University faculty
University of North Carolina at Greensboro alumni
21st-century American male writers
Year of birth missing (living people)

Keith Lee Morris


The Fort de Joux () or Château de Joux () is a castle, later transformed into a fort, located in La Cluse-et-Mijoux in the Doubs department in the Jura Mountains of France. It commands the mountain pass Cluse de Pontarlier.

History

The Château de Joux has undergone several transformations. The original structure was built in the 11th century and was made of wood. Over the next century, the lords of Joux rebuilt the keep and the external fortifications out of stone. In 1454, Philip the Good, Duke of Burgundy, bought the château and transformed it into a border fort, adding a moat and barracks. The château then passed to Charles the Bold, Mary of Burgundy, Maximilian I, Holy Roman Emperor (Habsburgs), Margaret of Austria, and Charles Quint, with each successive owner making further improvements. Its most famous remodeler was Vauban, who modernised it between 1678 and 1693.  It was finally annexed by France in 1678 under Louis XIV.

The Austrians captured the château in 1814. Later, the construction of the forts at Larmont in the 19th century provided reinforcement. In 1879, Captain (later Marshal) Joseph Joffre, then a military engineering officer, modernised the château and transformed it into a fort included in the Maginot Line to prevent German invasion from Swiss territory.

It served as a prison for successive French governments between the 17th and the 19th centuries. In that capacity, the château is best known for imprisoning several famous figures, including Mirabeau, Heinrich von Kleist, and the leader of the Haitian Revolution, Toussaint Louverture, who died there on 7 April 1803.

In addition to being used as a prison, the château played a part in the defence of the region until the First World War.

The fortress currently houses a museum of arms that exhibits more than 600 rare weapons dating from the early 18th to the 20th centuries, including a rare 1717 rifle. The castle also has a well which, at , was once the deepest in France. Cut with a horizontal gallery and partially filled, it is now the third deepest at about .

Since 1949, the French Ministry of Culture has listed the château as a monument historique.

See also
 List of castles in France

References

Sources
 Caroit, Jean-Michel, "L'INDEPENDENCE DE LA PREMIERE REPUBLIQUE NOIRE – 1er JANVIER 1804", Le Monde, 2 January 1904. (Archived from the original, 7 June 2004. Website contains translation and apparently the original.
 Francerama (travel website)

External links

 Le Château de Joux' website
 The Louverture Project: Fort de Joux

Castles in Bourgogne-Franche-Comté
Forts in France
Defunct prisons in France
Monuments historiques of Bourgogne-Franche-Comté
Museums in Doubs
Military and war museums in France
Vauban fortifications in France

Fort de Joux


, formerly , is a Japanese diversified retail holding company. It is one of the largest retail companies in Japan, owning Aeon hypermarkets, Aeon Mall and Aeon Town shopping malls, Daiei, MaxValu, Maruetsu, and My Basket supermarkets, Ministop convenience store, Welcia drugstore, and Aeon Cinema movie theaters.

Aeon traces its origins back to 1758 during the Edo period in Japan when it was established as a small sundry goods store called Shinohara-ya. Later, it was renamed Okada-ya after the founding family. In 1970, Okada-ya merged with several other companies it had established and became Jusco. Through a series of mergers and acquisitions, Jusco expanded its business and in 2001 changed its name to Aeon, which was its own brand. In 2010, Aeon merged with its subsidiary retail companies and consolidated all its hypermarket brands such as Jusco and Saty under the Aeon name. In 2021, Aeon was reportedly the 17th largest retailer in the world in terms of revenue.

Naming
The name Aeon is a transliteration from the koine Greek word  (ho aion), from the archaic   (aiwon). The name and symbolism used in the branding implies the eternal nature of the company.

History
 is the acronym for Japan United Stores Company, a chain of "general merchandise stores" (or hypermarket) and the largest of its type in Japan.

The various Jusco companies are subsidiaries of the Aeon supermarket chain.

The Jusco name was adopted in 1970 from a company founded as a kimono silk trader in 1758. Renamed Aeon in 1989, it operates stores throughout Japan under Jusco and other names and also has a presence in Malaysia, Hong Kong, mainland China and Thailand.

As of March 1, 2011, all Jusco and SATY stores under the Aeon umbrella in Japan changed their names to Aeon while all the Jusco stores and shopping centres in Malaysia have been fully re-branded into Aeon since March 2012. The Hong Kong and Mainland China subsidiaries officially changed their name to Aeon on 1 March 2013.

International ventures

Malaysia
In 1985, the first Jusco store outside Japan was opened in Plaza Dayabumi, Kuala Lumpur, Malaysia, as a jointly-owned company with Cold Storage and three local companies, known as Jaya Jusco. It was the first time that a Japanese company had entered into a significant joint venture in the Malaysian retail industry. Jusco assumed total operational control of the chain in 1988. Currently. there are 62 Aeon (formerly known as Jusco) Retails stores and shopping centres are in operation in Malaysia.

The oldest (though not the first) Jusco store in Malaysia is Jusco Taman Maluri in Cheras, Kuala Lumpur. It opened on 30 October 1989.

The Aeon Bukit Tinggi Shopping Centre in Bandar Bukit Tinggi, Klang, Selangor, Malaysia is the largest Jusco in Malaysia and Southeast Asia with over  of built-up area and 5,000 car park bays.

Jusco in Malaysia is notable for being among the first general merchandise chains to introduce biodegradable polybags made from sweet potatoes.

In March 2012, all the Jusco stores and shopping centres in Malaysia were re-branded to Aeon, following the decision of Aeon in Japan.

In April 2018, Aeon expanded to East Malaysia by opening their first mall in Kuching.

Vietnam
The first Jusco store "AEON MALL Tan Phu Celadon" opened on January 11, 2014, in Ho Chi Minh City at Tân Phú district. On October 28, 2015, Hanoi opened its first Jusco store "AEON MALL Long Bien" with an investment of 200m USD. Vietnam has currently about 200 Junco stores including 6 malls and several supermarkets. Junco has announced in 2023 that the first Aeon mall will open in Central Vietnam in the city of Huế in 2024.

Cambodia
First Junco store in Cambodia was opened on June 30, 2014, in Phnom Penh at Tonlé Bassac district. As of September 2023, Cambodia has three Aeon Malls, all of them located in the capital Phnom Penh.

Hong Kong

The Hong Kong Jusco subsidiary was established in November 1987 as Jusco Department Store Co. Ltd. The first Jusco store opened in Kornhill in December 1987 (another name for this store was Quarry Bay Main and Flagship store). It was listed in Hong Kong Exchanges and Clearing Limited on 4 February 1994 with the stock code 984.

Hong Kong Jusco has now been renamed as Aeon Stores (Hong Kong), and mainly manages shopping malls and other retail shops such as supermarkets, discount shops, home places, convenience stores and department stores. They offer low-cost and convenient daily necessities to customers including food, clothes, household items and electrical appliances. As of March 2013, there are eight Aeon General Merchandise Stores (GMS) in Hong Kong, seven branches of Aeon Supermarkets, 22 branches of Living Plaza by Aeon, 4 branches of BENTO EXPRESS by Aeon, 2 Aeon Style stores and only one branch of Aeon MaxValu Prime, which is located at The One, Tsim Sha Tsui.

Taiwan
Taiwan Jusco are subsidiaries of Taiwan Aeon Stores Co., Ltd. The first Jusco was in Windance in Hsinchu City. It was operated in 2003.  The second Jusco was operated in December 2005 at New Taipei city global mall.

China

In Mainland China, Jusco uses Aeon and Jusco for its name.  From 1996, Aeon Co., Ltd created many shopping mall named Jusco.  In Shanghai, there was a Jusco before, but it divested finance finally because of poor management.  In Guangdong, Guangdong Jusco Co., Ltd used the name "Jusco" to operate the first Jusco at 1996.  Now, there are thirteen shops in Guangdong.  Otherwise, Aeon also operated large shopping mall in Beijing and Shunde.  It also planned to expand to North China. In Shenzhen, Aeon () has  a number of large stores including one at Coastal city (Houhai station ).

Other countries
The largest Jusco (also the largest single-building shopping center in Japan) opened in 2005 in Mito.

All Juscos, have been closed down in Bangkok, Thailand. Aeon Co., Ltd. and now use the MaxValu name instead.

The company was legally incorporated in September 1926 as Okadaya (founded in 1758). In 1970, Okadaya merged with Futagi and Shiro to form Jusco Co., Ltd. The employees voted to name the company "Japan United Stores Company".

On August 21, 2001, the company became Aeon Co., Ltd.

On August 21, 2008, the corporate structure changed. Aeon Co., Ltd. became a holding company while Aeon Retail Co., Ltd. took over the retail operations formerly held by Aeon Co., Ltd.

As of March 1, 2011, all Jusco and Saty stores under the Aeon umbrella in Japan officially changed their names to Aeon while all the Jusco stores and shopping centres in Malaysia were fully re-branded into Aeon since March 2012. However, Jusco stores still operate in the Greater China region and some others.

In November 2012, Aeon acquired the operation of Carrefour Malaysia with an enterprise value of €250 million. All of the current Carrefour hypermarkets and supermarkets in Malaysia were then fully re-branded into Aeon BiG. The acquisition of Carrefour Malaysia made Aeon as the second largest retailer in Malaysia, which combined the sales from Aeon Retail stores (formerly known as Jusco) and the former Carrefour outlets. Post-acquisition, Aeon's ASEAN business vice president said the retail giant targeted to open 100 outlets in various formats in the country by year 2020.

Aeon Stores (Hong Kong) Co., Limited was established in Hong Kong in November 1987 and listed on the Hong Kong Stock Exchange in February 1994. Aeon aims to develop a chain operation in Hong Kong and offer value-for-money merchandise to Hong Kong customers.

See also

 Don Quijote (store)
 Maxvalu Tokai

References

 Aeon Financial Results for FY 2010 (ended on February 28, 2012)

External links

1758 establishments in Japan
1970s initial public offerings
Companies based in Chiba Prefecture
Companies listed on the Tokyo Stock Exchange
Holding companies of Japan
Holding companies established in 1758
Japanese brands
Multinational companies headquartered in Japan
Supermarkets of Japan
Retail companies established in 1758
Retail companies of Japan
Department stores of Malaysia
Retail companies of Malaysia

Aeon (company)


A rotation government or alternation government is one of the ways of forming of a government in a parliamentary state. It is a government that, during its term, will see the individual holding the post of prime minister switch (or "rotate"), whether within the same political bloc or as part of a grand coalition. Israel has seen by far the most experience with such a governing arrangement. The governments of Ireland and Bulgaria are now in their first rotation agreement. Usually, this alternation is guided by constitutional convention with tactical resignation of the first officeholder to allow the second to form a new government. Israel, which established the rotation mechanism in 1984, codified it in 2020.

, rotation governments have been formed in Ireland, Israel, Malaysia, North Macedonia, Romania, and Turkey. Successful rotations have only taken place in Israel (first with the rotation between Shimon Peres and Yitzhak Shamir, and second with the ascension of Yair Lapid to the office of the Prime Minister of Israel on 1 July 2022, fulfilling the agreement of his coalition government), Ireland (with Leo Varadkar returning as Taoiseach in December 2022) and Romania (with the rotation between Nicolae Ciucă and Marcel Ciolacu in June 2023); in all other cases, either the rotation has not yet taken place or the government has collapsed before it could occur. A rotation government was considered after the 2005 German federal election.

Bulgaria

Greek mythology
In the writings of Diodorus and the Bibliotheca of Pseudo-Apollodorus, Oedipus's sons Eteocles and Polynices agreed to share the kingship of Thebes, switching each year. When Eteocles's first year as king ended, he refused to give up the kingship, exiling Polynices, who found allies in Argos to retake the city, recounted in the events of Seven Against Thebes.

Germany
After the 2005 German federal election, a rotation government between the CDU and the SPD was considered; under it, then-incumbent SPD Chancellor Gerhard Schröder would have continued to serve until 2007, at which point the CDU's Angela Merkel would take over for the remaining two years. The CDU rejected this and opted for a grand coalition without rotation, with Merkel holding the Chancellery for the entire term.

Ireland

After the 2020 Irish general election a coalition of Fianna Fáil, Fine Gael and the Green Party was formed on 27 June 2020 on the basis of a rotation government. Micheál Martin of Fianna Fáil became Taoiseach with an agreement that Leo Varadkar of Fine Gael would serve as his deputy (Tánaiste) until December 2022, when he would become Taoiseach. The rotation took place on 17 December 2022, with Varadkar sworn in for his second non-consecutive term as Taoiseach, and Martin taking the role of Tánaiste.

Israel

Israel was the first country to employ a rotation government ( memshelet rotatzia) in 1984, following the negotiations for the forming of a grand coalition government after the inconclusive 1984 election. The 1984 rotation deal was non-binding; de jure, the rotation government was two successive governments, one formed in 1984 and headed by Alignment's Shimon Peres and another formed in 1986 and headed by Likud's Yitzhak Shamir, but whose membership and portfolio distribution were otherwise identical. In addition, since the 1984 rotation government was formally two "ordinary" governments, the prime minister could unilaterally dismiss ministers from the alternate prime minister's bloc: In fact, Shimon Peres forced the  Likud finance minister, Yitzhak Moda'i, to resign, despite Shamir's objections.

In the 2015 Israeli legislative election, the Zionist Union originally floated the idea of forming an intra-party rotation government between its co-leaders Isaac Herzog and Tzipi Livni, in which Herzog would serve for the first two years and Livni for the second two, though Livni announced on 16 March 2015 that only Herzog would serve as prime minister of a Zionist Union-led government.

The idea of a rotation-based grand coalition again took hold during the 2019–2022 Israeli political crisis and the negotiations for the forming of the 35th Israeli government after the elections to the 23rd Knesset, but unlike in 1984, broad changes in the Basic Law: The Government were made to establish a legally-binding rotation, under a mechanism known as an "alternation government" ( memshelet chilufim). Under these changes, the initial prime minister's term automatically expires when the rotation time comes and he swaps positions with the alternate prime minister, without the need to form a de jure new government. Under the law, the alternate prime minister's status is legally entrenched - for example, the prime minister must obtain the approval of the alternate prime minister before removing ministers from the latter's bloc.

The first official alternation government was the 35th Israeli government, with the rotation being made between the Likud (Benjamin Netanyahu) and Blue and White (Benny Gantz). The two parties identified the rotation deal as a central part of their coalition agreement. The High Court of Justice heard a petition (brought by the Movement for Quality Government, Meretz, and others) challenging the Basic Law authorizing rotation agreements, but a nine-justice panel decided in 2021 that such agreements do "not amount to the denial of the basic democratic characteristics of the State of Israel" and that the judiciary thus could not intervene.

Under the agreement, Netanyahu was prime minister and Gantz was alternate prime minister. The two were to swap positions on November 17, 2021, after Netanyahu spent 18 months as PM. However, the scheduled rotation never occurred, because the government collapsed after six months, after Netanyahu maneuvered to sink the passage of the 2020 state budget, trigging new elections in March 2021; the move blocked Gantz from becoming PM.

The 36th Israeli government, a broad-based coalition government of eight parties formed after the 2021 Israeli legislative election, ousted Benjamin Netanyahu as prime minister. As part of the coalition agreement, the parties agreed that Yamina's Naftali Bennett would serve as prime minister of Israel for two years starting in 2021, while Yesh Atid's Yair Lapid was named as alternate prime minister and would take over as PM for two years starting in September 2023. After the coalition lost its majority, leading to its collapse, Bennett and Lapid announced new elections (the fifth Israeli elections in four years) on November 1, 2022. The Knesset formally dissolved on 30 June 2022; on the same day, in accordance with the 2021 agreement, Lapid became prime minister, serving in a caretaker capacity until the elections four months later.

Characteristics since 2020
In an alternation government, as established by the 2020 amendments to Basic Law: The Government, the alternate prime minister is an office held either by a member of the Knesset who is designated to serve as prime minister later in a government or a member of the Knesset who has already served as the prime minister earlier in a government and has since rotated out of that position. The incumbent prime minister and alternate prime minister are sworn in together.

In the following cases, the alternate prime minister will replace the incumbent prime minister:
 the termination of the incumbent prime minister's term.
 the resignation of the incumbent prime minister from the position of prime minister
 the death of the incumbent prime minister.
 the passing of 100 days, in which the incumbent prime minister has been incapacitated for health reasons only.
 the resignation of the incumbent prime minister from the Knesset.

The law stipulates that "the number of ministers identified as having an affinity for the prime minister will be equal to the number of ministers who are identified as having an affinity for the alternate prime minister; However, if the number of ministers shall not be equal, the government will establish a voting mechanism according to which the voting power of all the prime minister-affiliated ministers shall be equal to the voting power of all the alternate-prime minister-affiliated ministers, or rules on how decisions will be taken to ensure such a ratio." The alternate-prime minister shall be acting prime minister.

Some of the clauses in Basic Law: The Government dealing with the incumbent prime minister will also apply to the alternate prime minister, including  Clause 18 (d), which stipulates that the prime minister's term expires upon his conviction in a final judgment on an offense in which he is infamous. The Basic Law stipulates that when the prime minister is convicted as aforesaid, the alternate prime minister will replace him, and when the alternate prime minister is convicted as aforesaid, the government will not be deemed to have resigned.

Malaysia
In the campaign for the 2018 Malaysian general election, the then-opposition Pakatan Harapan announced that, if a PH-led government would be formed, Mahathir Mohamad would initially serve as its Prime Minister and secure a pardon for jailed opposition leader Anwar Ibrahim, and that the premiership would be subsequently yielded to Anwar Ibrahim after his release. While Anwar Ibrahim was released from prison on 16 May 2018, the planned rotation did not happen by the time of the collapse of the Mahathir-formed government on 1 March 2020.

North Macedonia
In the campaign for the 2020 North Macedonian parliamentary election, the Democratic Union for Integration made its participation in any coalition contingent on the nominee for Prime Minister being an ethnic Albanian, which both the Social Democratic Union of Macedonia and VMRO-DPMNE have refused. On 18 August, the SDSM and DUI announced that they had reached a deal on a coalition government as well as a compromise on the issue of an ethnic Albanian Prime Minister. Under the deal, SDSM leader Zoran Zaev will be installed as Prime Minister, and will serve in that position until no later than 100 days from the next parliamentary elections. At that time, the BDI will propose an ethnic Albanian candidate for Prime Minister, and if both parties agree on the candidate, that candidate will serve out the remaining term until the elections.

Romania
The Ciucă Cabinet is the first rotation government which took power in Romania, of which members are the PSD, PNL and UDMR. The government took power in 2021 with Nicolae Ciucă of PNL as Prime Minister, with a successful rotation between the PNL and the PSD in 2023, after which Marcel Ciolacu's government took power, which would lead Romania until the next legislative elections.

Turkey
The 53rd government of Turkey was planned to be a rotation government between the True Path Party (DYP) and Motherland Party (ANAP), with the premiership alternating between the two parties every year. The vote of confidence was declared invalid by the Constitutional Court as an absolute majority of deputies was not obtained.

The 54th government of Turkey was planned to be a rotation government between the Welfare Party (RP) and DYP. Initially, Necmettin Erbakan of RP was the prime minister and Tansu Çiller of DYP was the deputy prime minister, with the rotation between the two taking place in 1997. When Erbakan resigned to ensure the rotation would take place, president Süleyman Demirel appointed Mesut Yılmaz of ANAP as the new prime minister instead.

See also
 The 1999 Indonesian presidential election (the power sharing pact between Abdurrahman Wahid and Megawati Sukarnoputri)
 The Granita Pact (the Blair–Brown deal)

References

Political science terminology

Rotation government


Steven Howse (born September 23, 1974), known professionally as Layzie Bone, is a rapper known primarily for being a member of the group Bone Thugs-n-Harmony. He has also gone by the names L-Burna and The #1 Assassin. He is the younger brother of fellow group member Flesh-N-Bone and cousin of group member Wish Bone. Layzie is also a member of the rap group Bone Brothers and CEO of the record label Harmony Howse Entertainment.

Music career
The group formed the band B.O.N.E. Enterpri$e (all except for Flesh-N-Bone) and recorded an album entitled Faces of Death in the studio of their then-mentor, Kermit Henderson, on his indie label Stoney Burke in 1993. After this Layzie and the rest of the Bone Family boarded a Greyhound Bus to Los Angeles where they worked with notable producer and rapper Eazy-E and his Ruthless/Relativity Records label. Diego Blak (born Diego Hodge), a marketer and promoter and co-executive producer of Faces of Death, introduced them to Eazy-E at a concert he promoted in Cleveland, Ohio, where they auditioned for him in his dressing room and then traveled back to Los Angeles after the show to seal the deal. At this point Eazy named them Thugs-n-Harmony but they wanted to keep the Bone name so they were called Bone Thugs-N-Harmony.

Solo career, Mo Thugs & Bone Brothers
Layzie has also promoted the indie label Mo Thugs Records which he and the rest of Bone originated. He released his first solo album Thug By Nature on March 20, 2001, exactly the same day Bizzy Bone released his second solo album, The Gift. He also has collaborative albums with Young Noble from The Outlawz and A.K. of Do or Die, solo albums out such as It's Not A Game, The New Revolution, Cleveland, Startin' from Scratch: How A Thug Was Born, and Thugz Nation. He has had a series of albums with Bizzy Bone; Still Creepin On Ah Come Up and under the name Bone Brothers entitled: Bone Brothers, Bone Brothers 2, Bone Brothers 3.

In the fall of 2010, Layzie established a new label, Harmony Howse Entertainment. In 2011, he and Fredro Starr of the Onyx group were planning on releasing a collaborative EP entitled FireSquad. Layzie would go on to release two separate albums The Definition and The Meaning on February 22, 2011 under his new label Harmony Howse Entertainment. In 2015 Layzie released the single Cleveland is The City Featuring Aaron "D-Boyy" Dissell. The song was used by Fox News during the 2015 NBA Finals as the Cleveland Cavaliers theme song. Layzie was also working on an album called Perfect Timing, which was originally scheduled to be released in 2016, but is now TBD. Layzie is the uncle of the independent rapper, Dizzy Wright.

During a brief feud with the Migos Layzie would release the album Annihilation on April 19, 2019 featuring the song  If was a 5th featuring Bizzy Bone, and the dis song Let me go Migo(Remix) . On August 16, 2019 Layzie would release another album Lost & Found. On July 6, 2020, Layzie Bone released an album titled Wanted Dead or Alive featuring Krayzie Bone, Flesh-N-Bone, Dame Dolla, Willy Ray, Cyrano ESQ, Maybach Dice, Paul Zero, Stew Deez, Ken Dawg, and Ebony Burks. On November 26, 2021, Layzie Bone released a new collaboration album with HC The Chemist titled Eyez on the Prize. On July 4, 2023 Layzie released a mixtape Too Eazy while announcing a new album called Hypnotic Rhythms which was set to be released with a new video in August 2023 but is now TBD.

Discography

Studio albums
Thug by Nature (2001)
The New Revolution (2006)
Cleveland (2006)
Startin' from Scratch: How A Thug Was Born (2007)
Thugz Nation (2008)
The Definition (2011)
The Meaning (2011)
Annihilation (2019)
Lost & Found (2019)
Wanted Dead or Alive (2020)

Collaboration albums
Bone Brothers with Bone Brothers (2005)
Thug Brothers with Young Noble (2006)
Bone Brothers 2 with Bone Brothers (2007)
Bone Brothers III with Bone Brothers (2008)
Still Creepin on Ah Come Up with Bone Brothers (2008)
Finally with A.K. (2008)
Thug Twinz with Big Sloan (2009)
Eyez On The Prize with HC The Chemist (2021)

References

External links
Layzie Bone

1975 births
Living people
African-American male rappers
American male rappers
American hip hop singers
Bone Thugs-n-Harmony members
Rappers from Cleveland
Gangsta rappers
RBC Records artists
21st-century American rappers
21st-century American male musicians
21st-century African-American musicians
20th-century African-American people
Mo Thugs members

Layzie Bone


Early Life:

Louis the Child was born in September or October 893 in Altötting, Duchy of Bavaria, to king Arnulf of Carinthia and his wife, Ota.

He had at least two brothers: his elder, illegitimate brother Zwentibold, who ruled Lotharingia, and another brother named Ratold, who briefly ruled the Kingdom of Italy.

East Francia:

Louis was crowned in Forchheim on 4 February 900 at the age of six and reigned until his death aged 17 or 18.

Due to his young age and weak personal constitution, the reins of government were entirely in the hands of others - the nobles and bishops.

The most influential of Louis's councillors were Hatto I and Solomon III (bishop of Constance).

Lotharingia:

Louis succeeded his elder illegitimate half-brother Zwentibold in Lotharingia after 900 and maintained a separate chancery for both regions.

He appointed an East Frankish duke Gebhard to rule Lotharingia, alienating the Lotharingian nobility.

The Lotharingian nobility did not participate in East Frankish assemblies.

Magyar Invasions:

During his reign, the country was ravaged by Magyar raids. The Magyar army devastated Bavaria, the Duchy of Carinthia, and twice ravaged the Duchy of Saxony.

In 904, Louis invited Kurszán, the kende of the Magyars, to negotiations, but killed him and his delegation.

In 907, the Magyars inflicted a heavy defeat on the Bavarians in the Battle of Pressburg, killing the Margrave Luitpold and many high nobles.

Death and Succession:

Louis the Child died at Frankfurt am Main on 20 or 24 September 911, aged seventeen or eighteen.

His death brought an end to the eastern branch of the Carolingian dynasty.

The dukes of East Francia elected Conrad of Franconia, son of Gebhard, as the king, while the nobles of Lotharingia elected the Carolingian Charles the Simple as their king.

Legacy:

Louis the Child was the last East Frankish ruler of the Carolingian dynasty.

He was buried in the monastery of Saint Emmeram's in Regensburg, where his father Arnulf also lay.

10th century in Germany
Carolingian dynasty

Louis the Child


The Rotherham Tramway was a tramway system serving the West Riding town of Rotherham. Service began on  31 January 1903 and ended on 13 November 1949.

The network of six lines spread across the town and was linked to the tramway networks of Sheffield and Mexborough & Swinton.

Rotherham tramways ran on six lines joining in the town's centre and serving Thrybergh, Silverwood Colliery and Broom Road to the East, Canklow and Sheffield to the South, Kimberworth to the West and Rawmarsh to the North.

The line to Sheffield was Rotherham's busiest as it served the main steel producing area of Great Britain. It required an almost constant flow of tramcars to meet demand. Track was re-laid in 1933 as well as single-ended double-decker tramcars purchased to serve on this particular line. Indeed, the line was built with loop termini. The tramcars used for the Sheffield-Rotherham service were equipped with only one entrance and staircase and like on traditional double-decker buses, seats were made to be comfortable. Tram service ended on this route in 1948 and Sheffield trams ended at Tinsley (where the change of owner occurred until 1926 when the Sheffield Corporation purchased the line up to Vulcan Road).

An extension of the line to Broom Top to Maltby was opened for trolleybuses in 1912, this being the third trolleybus line in Great Britain. Trolleybuses were permitted to reach the town centre in 1924 along with trams. Tram routes to Rawmarsh Road, Broom Road, Kimberworth and Thrybergh were converted to trolleybuses in 1929 and 1931. The line to Canklow was converted to motorbuses in 1934.

Double-decker trolleybuses were built from the single-deck fleet from 1955. Twenty-three of these were sold in Spain with the last trolleybus running in 1965.

Trams returned to Rotherham in October 2018 when the Sheffield Supertram was extended to Rotherham Parkgate.

References

Rotherham
Tram transport in England
Rail transport in South Yorkshire
1903 establishments in England
1949 disestablishments in England

Rotherham Tramway


Ngwane III was King of kaNgwane from 1745 to 1780. He is considered to be the first King of modern Eswatini. For his name the people were called bakaNgwane and the country was called kaNgwane or lakaNgwane. Ngwane was the son of Dlamini III and Queen LaYaka Ndwandwe.
Dlamini was succeeded by Ngwane III his son with Queen LaYaka Ndwandwe. He took over the Dlamini chieftaincy
and established settlements south of the Pongola River, later moving them to the north of the river banks. This makes Ngwane and his followers the founders of modern Swaziland.
Ngwane ruled his Kingdom from the south east of Swaziland in the present Shiselweni district and his headquarters were called Zombodze at the foot of the Mhlosheni hills.
It was at Zombodze that the Nguni ceremony incwala was celebrated for the first time.

Kingship

Ngwane III is an important figure in the history of Eswatini and he is regarded the first King of modern Eswatini. He succeeded his father Dlamini III as chief of the early Swazi who had settled near the Pongola River and Lubombo Mountains. He managed to conquer land south of the Pongola River. He wasn't able to hold this land, but it is this land which is still seen as an important part of modern Swaziland. Later he settled on the northern side of the Pongola and subsequently moving his royal capital to Zombodze, within the borders of present-day Eswatini. Zombodze became the heartland of the Ngwane kingdom, and incwala, the Nguni ceremony of First Fruits was celebrated for the first time there. Ngwane thus became the eponym of his country and his people. The country became known as kaNgwane, means "the country of place of Ngwane" and his people as bakaNgwane. This name is still used today and the Swazi people use this name to refer to themselves as a people. Ngwane III reigned until 1780 when his son, Ndvungunye, became King after a regency of Queen LaYaka Ndwandwe.

References

See also
List of kings of Swaziland

Swazi monarchs
18th-century monarchs in Africa
Year of birth missing
1780 deaths
Monarchies of South Africa

Ngwane III