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This study was supported by the BBSRC (grant no. BB/F008783/1); additional support was given by The Isaac Newton Trust (Trinity College, Cambridge, U.K.) and the Department of Zoology (University of Cambridge, U.K.).
Original Research
Cellular basis for singing motor pattern generation in the field cricket (Gryllus bimaculatus DeGeer)
Article first published online: 3 SEP 2012
DOI: 10.1002/brb3.89
© 2012 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
Brain and Behavior
Volume 2, Issue 6, pages 707–725, November 2012
Additional Information
How to Cite
Brain and Behavior 2012; 2(6): 707–725
Publication History
- Issue published online: 9 NOV 2012
- Article first published online: 3 SEP 2012
- Manuscript Accepted: 30 JUL 2012
- Manuscript Revised: 17 JUL 2012
- Manuscript Received: 6 JUN 2012
Funded by
- BBSRC. Grant Number: BB/F008783/1
- The Isaac Newton Trust (Trinity College, Cambridge, U.K.)
- Department of Zoology (University of Cambridge, U.K.)
- Abstract
- Article
- References
- Cited By
- Acoustic communication;
- central pattern generator;
- identified interneuron;
- insect;
- species-specific motor pattern;
- stridulation
The singing behavior of male crickets allows analyzing a central pattern generator (CPG) that was shaped by sexual selection for reliable production of species-specific communication signals. After localizing the essential ganglia for singing in Gryllus bimaculatus, we now studied the calling song CPG at the cellular level. Fictive singing was initiated by pharmacological brain stimulation. The motor pattern underlying syllables and chirps was recorded as alternating spike bursts of wing-opener and wing-closer motoneurons in a truncated wing nerve; it precisely reflected the natural calling song. During fictive singing, we intracellularly recorded and stained interneurons in thoracic and abdominal ganglia and tested their impact on the song pattern by intracellular current injections. We identified three interneurons of the metathoracic and first unfused abdominal ganglion that rhythmically de- and hyperpolarized in phase with the syllable pattern and spiked strictly before the wing-opener motoneurons. Depolarizing current injection in two of these opener interneurons caused additional rhythmic singing activity, which reliably reset the ongoing chirp rhythm. The closely intermeshing arborizations of the singing interneurons revealed the dorsal midline neuropiles of the metathoracic and three most anterior abdominal neuromeres as the anatomical location of singing pattern generation. In the same neuropiles, we also recorded several closer interneurons that rhythmically hyper- and depolarized in the syllable rhythm and spiked strictly before the wing-closer motoneurons. Some of them received pronounced inhibition at the beginning of each chirp. Hyperpolarizing current injection in the dendrite revealed postinhibitory rebound depolarization as one functional mechanism of central pattern generation in singing crickets.
In all animals, including man, rhythmically repetitive movements such as breathing, walking, or flying are driven by central pattern generator (CPG) networks of the central nervous system (CNS) (Delcomyn 1980). Systematic identification of CPG neurons and their synaptic connections revealed the functional circuitry of several small CPG networks (Marder et al. 2005). By analyzing cellular and network mechanisms underlying rhythmic pattern generation (Marder and Calabrese 1996; Selverston 2010), invertebrate model systems provided the conceptual foundation to understand how similar circuits may operate in more complex brains (Pearson 1993; Yuste et al. 2005; Clarac and Pearlstein 2007; Harris-Warrick 2010).
The rhythmic output of a CPG originates either from emergent network properties deriving from mutual synaptic coupling between interneurons (e.g., locomotory rhythms, Satterlie 1985), endogenous bursting properties of individual pacemaker cells (e.g., respiration in mammals, Paton et al. 2006), or as a combination of both mechanisms (e.g., leech heart, Cymbalyuk et al. 2002). Even though all CPG circuits can endogenously produce rhythmic motor patterns without sensory feedback or other rhythmic inputs, most CPGs are nevertheless extensively modulated by sensory feedback (Pearson 1995; Beenhakker et al. 2005; Büschges and Gruhn 2008) and neuromodulators (Dickinson 2006; Harris-Warrick 2011) to allow flexible adjustment to varying external conditions (Pearson 2000).
Besides locomotion, intraspecific communication with stereotypically repeated visual, vibratory, or acoustic signals is also based on centrally generated rhythmic motor activity. Crickets are a well-established model system for studying principles of species-specific acoustic communication (e.g., Huber 1962; Hoy and Paul 1973; Schildberger 1994; Poulet and Hedwig 2006; Schöneich and Hedwig 2010; Grace and Shaw 2011). The males produce a genetically fixed calling song pattern (Bentley and Hoy 1972) that has to match the sharply tuned auditory recognition mechanism of the conspecific females (Pollack and Hoy 1979; Weber and Thorson 1989). However, the neuronal network that generates the singing motor pattern is still a virtually uncharted area (reviews: Kutsch and Huber 1989; Elsner 1994; Gerhardt and Huber 2002). From his pioneering studies, Huber (1955, 1960) initially concluded that the singing pattern is generated in distinct neuropiles of the cricket brain. Following experiments, however, demonstrated that the head ganglia are not directly involved in the central pattern generation of the crickets calling song (Otto 1971; Kutsch and Otto 1972). A pair of descending brain neurons merely controls the singing behavior by serving as command neurons that activate the singing CPG with their tonic spike discharge (Hedwig 2000). As the mesothoracic ganglion houses the motoneurons, which are driving the sonorous wing movements, for some decades it was surmised that the singing CPG is also located in this ganglion (review: Kutsch and Huber 1989). Recent studies, however, demonstrated that the neural network that generates the singing motor pattern spans from the metathoracic (Hennig and Otto 1995) to the first unfused abdominal ganglion (Schöneich and Hedwig 2011), and preliminary experiments reported an ascending singing interneuron in the first unfused abdominal ganglion, which elicited and reset the singing motor pattern when stimulated with intracellular current injection (Schöneich and Hedwig 2011).
To further investigate the neuronal mechanisms underlying singing pattern generation in the cricket CNS, here we quantitatively analyzed the rhythmic spike activity of wing-opener and wing-closer motoneurons during fictive singing, and we systematically probed the ventral nerve cord with sharp microelectrodes to identify and analyze interneurons of the singing network.
Materials and Methods
Male Mediterranean field crickets (Gryllus bimaculatus DeGeer) were selected 5–20 days after their final molt from the colony at the Department of Zoology (University of Cambridge, U.K.) and maintained under crowded conditions at 28°C on a 12h:12h light:dark cycle. Nearly 400 crickets were used for this study. After the preparation, about 50% sang for extended periods of time to allow exploring the ventral nerve cord with intracellular recordings and to narrow down the regions of the singing network. Presented data are based on recordings in 38 crickets. Experiments were carried out at 20–25°C and complied with the principles of Laboratory Animal Care.
Preparation and pharmacological brain stimulation
After removing legs and wings, crickets were opened by a dorsal longitudinal incision and pinned out ventral side down onto a plasticine-covered platform. The thoracic and anterior abdominal ganglia were exposed for intracellular recordings, and their peripheral nerves were cut. The head was waxed to a moveable metal support, and a small window was cut in the frontal head capsule to gain access to the brain. Fictive singing was elicited by pressure injection (Pneumatic PicoPump PV820; WPI, Sarasota, FL) of the acetylcholine esterase inhibitor eserine (10−2 mol/L in saline; Sigma-Aldrich, St Louis, MO) into the ventral protocerebrum using a blunt glass microcapillary (Fig. 1A; cf. Wenzel and Hedwig 1999; Poulet and Hedwig 2002). Exposed ganglia were continuously rinsed in Ringer's solution for crickets (ionic concentrations in mmol/L: NaCl, 140; KCl, 10; CaCl2, 7; NaHCO3, 8; MgCl2, 1; N-trismethyl-2-aminoethanesulfonic acid, 5; d-trehalose dihydrate, 4; pH 7.4).
Electrophysiological recordings
After severing all thoracic sensory and motor nerves, the motor pattern of fictive singing was recorded extracellularly from the truncated mesothoracic wing nerve 3A (labeled in this article as T2-N3A) using either a double-hook or a suction electrode (Fig. 1B). The signal was amplified with a differential AC amplifier (Model 1700; A-M Systems, Sequim, WA). For intracellular recordings with sharp microelectrodes, the respective ganglion was stabilized between a silver ring and a subjacent silver platform with an embedded optic fiber for brightfield illumination. The microelectrodes were pulled (DMZ-Universal Puller, Zeitz-Instruments, Martinsried, Germany) from borosilicate glass capillaries (GC100F-10, Harvard Apparatus Ltd., Kent, U.K.). Tips were filled with either 4% Lucifer Yellow (Sigma-Aldrich, St Louis, MO) or 5% neurobiotin (Vector Laboratories, Burlingame, CA), and the shaft was backfilled with 1 mol/L lithium chloride or 2 mol/L potassium acetate, respectively. Microelectrodes had final resistances of 90–130 MΩ. Intracellular recorded signals were amplified using a DC amplifier (BA-01X, NPI, Tamm, Germany). All recordings were monitored with an analog oscilloscope (Tektronix 5440) and simultaneously digitized with a 40 kHz sampling rate per channel (Micro1401 mk II, CED, Cambridge, U.K.) for storage on a PC hard drive.
Structure and terminology of neurons
For anatomical identification, intracellularly recorded neurons were labeled by iontophoretic tracer injection. The ventral nerve cord was subsequently dissected and processed following conventional protocols for Lucifer Yellow (Hedwig 1986) and neurobiotin (Schöneich et al. 2011) labeled whole-mount preparations. Successfully stained neurons were photographed using a digital SLR camera (Canon EOS 350D) attached to a fluorescence microscope (Axiophot, Zeiss, Germany) or scanned with a confocal laser-scanning microscope (Leica SP5, Wetzlar, Germany). The morphology of neurons was graphically reconstructed from the digital image stacks using ImageJ 1.44o (National Institutes of Health, Bethesda, MD). The acronyms given to the identified interneurons reflect morphological and functional features. The first two digits stand for the neuromere housing the cell body. In crickets, the metathoracic ganglion is a fused complex of the metathoracic (T3) and two abdominal (A1 and A2) neuromeres, and the first unfused abdominal ganglion is build by the A3 neuromere. The next two digits indicate by the letter A, D, or L whether it is an ascending, descending, or local interneuron and O or C stands for rhythmic excitation in phase with the wing-opener or wing-closer motoneurons during singing, respectively.
Data analysis
Electrophysiological data were analyzed with Spike2 (CED, Cambridge, U.K.) and Neurolab (Knepper and Hedwig 1997). The first spike of the wing-opener and wing-closer motoneuron bursts in nerve T2-N3A was used for interval measurements within the motor pattern and also for delay measurements between interneuron and motor activity. If not stated otherwise, normally distributed data are given as mean ± standard deviation (mean ± SD) and when normality tests failed (Prism 5.0, GraphPad, La Jolla, CA), median and interquartile range (IQR) were used instead. In pooled data sets, each contributing animal is equally represented (N, number of animals; n, number of stimulations or events).
Motor pattern of fictive singing
Male crickets sing by rhythmically opening and closing their front wings and thereby produce a short sound pulse (also called syllable) during each closing movement. In the calling song of Gryllus bimaculatus, chirps consisting of 3–5 pulses are perseveringly repeated at a rate of 2–3 Hz, and pulses are generated at a rate of 20–30 Hz within the chirps (Doherty 1985; Verburgt et al. 2011). After severing all sensory and motor nerves of the thoracic ganglia, we elicited fictive singing by pharmacological stimulation of the command neurons in the brain (Fig. 1A; cf. Wenzel and Hedwig 1999). The singing motor pattern was recorded from the left mesothoracic nerve T2-N3A, which contains several axons of wing-opener and wing-closer motoneurons. Thus, the pulse pattern, which constitutes the chirps, is reflected by rhythmically alternating opener- and closer-motoneuron spike bursts in the nerve recordings (Fig. 1B; cf. Poulet and Hedwig 2002). In order to distinguish between the acoustic pulse and the underlying biphasic opener–closer motorcycle, we will refer to the latter as "syllable" as these encompass a silent and sonorous section. To compare the fictive motor pattern with the temporal characteristics of the natural calling song, we quantitatively analyzed the wing-nerve recordings of five males that produced sustained singing episodes with 3-, 4-, and 5-syllable chirps.
In the majority of animals, singing activity started within 20 min after eserine injection and then lasted up to 3 h in some specimen. For episodes of fictive singing with either 3-, 4-, or 5-syllable chirps, the chirp rate decreased significantly with 2.9 ± 0.2, 2.6 ± 0.2, and 2.3 ± 0.3 Hz, respectively (mean ± SD; N = 5, n = 50; t-tests: P < 0.001 for each combination; Fig. 1C). This was due to an increase in the chirp duration with each additional syllable generated (108 ± 7, 148 ± 10, and 192 ± 12 msec for 3-, 4-, and 5-syllable chirps, respectively; N = 5, n = 50; t-tests: P < 0.001 for each combination). In contrast, regardless of the chirp duration, the chirp intervals ranged between 210 and 256 msec (IQR; median = 233 msec; N = 5, n = 150).
When pooled over the five animals, the mean syllable rate was 23.8 ± 2.2 Hz (mean ± SD; N = 5, n = 450). From the beginning to the end of a chirp, however, consecutive syllables became longer, resulting in a gradual decrease in the instantaneous syllable rate (Fig. 1D). For 5-syllable chirps, the consecutive syllable repetition rates were 25.5 ± 2.3, 24.3 ± 1.6, 23.3 ± 1.6, and 21.8 ± 1.7 Hz; for 4-syllable chirps 25.3 ± 2.2, 24.3 ± 2.1, and 22.6 ± 2.0 Hz; and for 3-syllable chirps 24.3 ± 1.8 and 22.6 ± 1.8 Hz (mean ± SD; N = 5, n = 50). The mean syllable rate of chirps was very consistent for each individual animal regardless of the syllable number, but between males it varied significantly in the range of 21–26 Hz (t-test: P < 0.0001 for seven of the 10 possible combinations between five animals; n = 90 each).
During fictive singing, an opener-to-closer interval of 21.5 ± 2.1 msec (N = 5, n = 600) and subsequent closer-to-opener interval of 21.0 ± 3.2 msec (N = 5, n = 450) were generated (lower trace in Fig. 1B). The average opener–closer interval differed significantly in a range from 20 ± 2 to 24 ± 1 msec between individual males (t-test animal min vs. animal max: P < 0.0001; n = 120 each), but was highly consistent for each animal regardless of instantaneous chirp or syllable rate and the number of syllables per chirp. Although with 21.2 msec (mean ± SD; N = 5, n = 150), the opener–closer interval of the first syllable in a chirp was in average by 0.4 msec shorter than the following (t-test first vs. second and first vs. third syllable: P < 0.01; second vs. third: P > 0.8; N = 5, n = 150 each), the progressively decreasing syllable rate within chirps (Fig. 1D) resulted mainly from the gradual lengthening of the closer–opener interval (Fig. 1E). For 5-syllable chirps, the closer–opener intervals of the consecutive syllables were 18.8 ± 2.2, 20.0 ± 2.1, 22.0 ± 2.8, and 24.8 ± 3.5 msec; for 4-syllable chirps, 18.6 ± 2.2, 20.2 ± 2.1, and 22.8 ± 2.7 msec; and for 3-syllable chirps, 19.6 ± 2.1 and 22.4 ± 2.3 msec (mean ± SD; N = 5, n = 50).
Cellular analysis of the singing network
Interneurons of the singing pattern generating network were intracellularly recorded and stained in the metathoracic ganglion (encompassing the T3, A1, and A2 neuromeres) and first unfused abdominal ganglion (A3 neuromere). Recent experiments had revealed that these two ganglia house the singing-pattern generator (Schöneich and Hedwig 2011). To test whether a recorded interneuron was part of the singing CPG, we modulated its spike activity by intracellular current injection and analyzed its impact on the ongoing motor pattern. An interneuron was considered a component of the singing CPG if its rhythmic activity strictly preceded the opener- or closer-motoneuron bursts and if transient perturbations of its activity reset or considerably altered the motor pattern. To quantitatively analyze the timing of interneuron activity with respect to the syllable rhythm, we used the spike burst onset of wing-opener and wing-closer motoneurons as temporal reference. The anatomical and physiological characteristics of individual singing interneurons are described in the following paragraphs.
Ascending opener-interneuron A3-AO
In the abdominal ganglion A3, we identified the interneuron A3-AO that discharged in phase with the syllable rhythm. This neuron was intracellularly recorded in 12 animals and subsequently stained with either Lucifer Yellow (N = 5) or neurobiotin (N = 3); it was described as A3-IN in a preliminary report by Schöneich and Hedwig (2011). The soma of A3-AO was located on the lateral margin of A3, the neurite crossed the ganglion midline close to the dorsal surface and its contralaterally ascending axon projected up to the prothoracic ganglion (Fig. 2A). At both sides of A3, the primary neurite gave off a large anterior and a smaller posterior dendrite. The ipsilateral and contralateral dendrites branched out bilateral symmetrically in the very dorsal neuropile of A3. In each neuromere of the three thoracic ganglia, one prominent anterior branch and one or two posterior branches arose from the main axon and projected dorsally toward the midline of the respective ganglion. A3-AO occurred as a bilateral pair of sibling neurons, and in all three neurobiotin-labeled specimen, the mirror-image sibling neuron was clearly stained as well (Fig. 3). Such dye coupling may indicate electrical coupling between the left and right A3-AO interneuron via gap junctions (cf. Ewadinger et al. 1994; Fan et al. 2005; Anava et al. 2009).
During fictive singing, the membrane potential of A3-AO, as recorded in its main dendrite, oscillated with the syllable pattern (Fig. 2B). In the opener phase of each syllable, it depolarized by 20–25 mV, and in the closer phase, it hyperpolarized 5–10 mV beneath resting potential. The depolarization preceding the first syllable of a chirp was up to 3.5 mV higher than the following. Every depolarization gave rise to a volley of 4–6 action potentials with a spike frequency of up to 380 Hz during the first syllable and 360 Hz during the following syllables of a chirp. The spike activity in A3-AO preceded the next opener burst in the wing nerve by 10.1 ± 0.8 msec (mean ± SD; N = 10) and the following closer burst by 29.2 ± 2.2 msec (mean ± SD; N = 10). Therefore, we refer to A3-AO as an opener interneuron. Interestingly, we never observed any synaptic inputs or spike activity in the A3-AO dendrite before and after singing episodes or during chirp intervals.
When a constant depolarizing current of 5 nA was injected into the dendrite of A3-AO, the interneuron responded with consistently repeated depolarization–hyperpolarization oscillations of its membrane potential generating a burst of 2–6 action potentials during each depolarization. This rhythmic interneuron activity reliably elicited alternating opener–closer motoneuron activity reflecting the normal syllable pattern in the ipsi- and contralateral wing nerves. Activation of a single A3-AO interneuron is therefore sufficient to continuously drive the motor pattern of the syllable rhythm. Current pulses of 500 msec elicited long chirps with 14–15 syllables (Fig. 2C) and pulses of 200 msec strictly elicited 6-syllable chirps. Injecting +5 nA for just 100 msec during the chirp interval caused strictly three additional depolarization–hyperpolarization cycles and the motor pattern of an additional 3-syllable chirp (Fig. 2D). Short current pulses (+5 nA; 10–20 msec), which fell entirely within a chirp, did not change the singing pattern. When injected during the chirp intervals, however, they reliably triggered a single membrane potential oscillation-cycle with at least two action potentials that strictly elicited the motor pattern of a single syllable.
Each additional chirp evoked by depolarizing current injection to A3-AO reliably reset the chirp rhythm of the singing activity (Fig. 2C and D). After the end of the stimulus, the subsequent chirp started with a delay of 230 ± 34 msec (N = 3, n = 51), which closely matched the duration of the normal chirp intervals (229 ± 20 msec; N = 3, n = 60) before current injection. Injection of 100 msec and 500 msec current pulses at different moments of the chirp cycle revealed a linear correlation between the stimulation phase and the resulting phase shift of the chirp rhythm (Fig. 2E). Plotted as a phase–response curve (Pinsker 1977), the data for 100 and 500 msec current pulses were closely fitted by the linear regression functions y = 1.28 × −0.35 (R2 = 0.95; N = 3, n = 34) and y = 1.37 × +0.75 (R2 = 0.92; N = 3, n = 17), respectively. The trend lines of the two data sets are vertically shifted by 1.1 chirp cycles (mean chirp cycle: 364 ± 43 msec; N = 3, n = 120), which precisely reflect the difference of 400 msec in stimulus duration. As A3-AO activation is sufficient to drive the syllable motor pattern and also reliably reset the chirp rhythm, this interneuron is clearly a pivotal element of the cricket singing CPG.
There was no significant difference between the average opener–closer intervals of fictive singing chirps (21 ± 1 msec; N = 3, n = 90) and chirps induced by current injection in the A3-AO dendrite (20 ± 2 msec; N = 3, n = 90). Just as in the fictive singing pattern, the opener–closer interval of the first syllable in the current-induced chirps was slightly shorter compared with the following (t-test first vs. second and first vs. third syllable: P < 0.01; second vs. third: P > 0.5; N = 3, n = 21 each). The closer–opener intervals, however, were significantly reduced (t-test: P < 0.0001; N = 3, n = 45) in current-induced chirps (mean ± SD: 15 ± 2 msec) compared with fictive singing (mean ± SD: 21 ± 2 msec) and did not show the successive increase as in natural chirps (Fig. 2F).
Sustained hyperpolarizing current injection was used to test if spike activity in both A3-AO sibling neurons is necessary to maintain fictive singing. Within 15–20 sec of injecting a constant −10 nA current in the dendrite of one A3-AO interneuron, fictive singing stopped and recurred not until 5–10 sec after the current injection. During the first seconds of hyperpolarization, the rhythmic spike activity in A3-AO was drastically reduced and even completely abolished for some individual syllables (Fig. 4A). This reduced activity in one A3-AO neuron, however, did not affect the ongoing singing motor activity, indicating that the single A3-AO interneuron is not necessary for the cycle-by-cycle generation of the singing motor pattern and the spike activity of the contralateral A3-AO neuron was presumably sufficient to transiently maintain the motor output. Interestingly, short hyperpolarizing current pulses (−5 nA; 100–1000 msec duration) in the A3-AO dendrite were immediately followed by additional membrane potential oscillations in this neuron (Fig. 4B). Although the depolarization amplitudes of the post-hyperpolarization response were considerably smaller (2–6 mV) than the opener-phase depolarizations during fictive singing (20–25 mV), A3-AO generated a burst of 3–5 action potentials during each poststimulus depolarization, which elicited a corresponding sequence of syllables in the motor pattern that reset the ongoing chirp rhythm (Fig. 4B).
The intracellular current injection experiments demonstrated the importance of A3-AO spike activity for the singing pattern generation. By gradual manipulation of its membrane potential, we asked if also subthreshold stimulation would modulate the singing activity. Ramp-like depolarizing and hyperpolarizing current with maximum amplitudes of only +0.5 nA and −0.5 nA was injected into the dendrite of A3-AO. This gently shifted the membrane potential of the neuron without changing the number of syllables per chirp (Fig. 5A) or even the spike activity underlying each syllable (A3-AO spikes per syllable: 0 nA, 4.7 ± 0.6; −0.5 nA, 4.7 ± 0.5; +0.5 nA, 4.6 ± 0.7; mean ± SD; N = 1, n = 25 each). The low-amplitude current injection did not influence the average chirp duration, which remained 176 ± 5 msec throughout the experiment. The duration of the chirp intervals (212 ± 18 msec; mean ± SD before current injection), however, progressively decreased with increasing depolarization (199 ± 15 msec for 0.1–0.3 nA; 192 ± 13 msec for 0.3–0.5 nA), whereas moderate hyperpolarization had no effect (Fig. 5B). Similarly, the initial syllable periods within the chirps were modulated by moderate depolarization but not by hyperpolarization (Fig. 5C). With increasing depolarization, the first syllable period in a chirp was lengthened by up to 4 msec, the second syllable period was shortened by up to 2 msec, and the following syllable periods did not change. These subtle modulations of the singing motor pattern indicate that the temporal structure of the motor output does not only depend on the spike activity but also on graded changes in the membrane potential of A3-AO.
Descending opener-interneuron T3-DO
Systematic probing the metathoracic neuromere with microelectrodes provided little evidence for the presence of singing interneurons. Only close to the border toward the A1 neuromere could we identify an interneuron with a contralateral descending axon that discharged in phase with the singing rhythm. The neuron was intracellularly recorded in 17 animals and subsequently stained with either Lucifer Yellow (N = 7) or neurobiotin (N = 3). The cell body of T3-DO was located on the lateral margin of the metathoracic ganglion just posterior to the root of nerve 5 (Fig. 6A). From there, the primary neurite ran dorsally along the border between the metathoracic and first abdominal neuromere toward the contralateral side. Near the midline of the ganglion, one prominent posterior and three anterior dendrites arose from the primary neurite. In all stained specimens, the most conspicuous feature of this neuron was the posteriorly projecting dendrite that branched along the dorsal midline of the two abdominal neuromeres (A1 and A2). The arborization patterns of the much thinner anterior dendrites varied considerably between animals. In the metathoracic ganglion, the contralateral descending axon had one medially projecting side branch in A1 and one in A2, which both ramified dorsally near the midline of the ganglion. In the unfused abdominal ganglia A3–A6, anterior and posterior axonal side branches projected in a similar way toward the dorsal midline neuropile, while the diameter of the descending axon decreased progressively and the axonal arborizations became less extensive from ganglion to ganglion. The axon of T3-DO typically terminated in A6, but in two animals, it descended as a very thin fiber toward the terminal ganglion.
Interneuron T3-DO fired bursts of 3–4 action potentials in phase with the syllable rhythm of fictive singing. Spike bursts started strictly 7.0 ± 0.8 msec (mean ± SD; N = 10) before the opener-motoneuron activity and 26.9 ± 3.2 msec (mean ± SD; N = 10) before the closer-motoneuron spike bursts (Fig. 6B), characterizing it as an opener interneuron. Recordings from the posterior dendrite revealed that the membrane potential clearly oscillated in phase with the syllable rhythm. In the opener phase, the dendrite depolarized by 4–6 mV, and in the closer phase, it hyperpolarized 7–8 mV below the resting potential. In recordings from the anterior main dendrite, the depolarization in the opener phase reached up to 14 mV and the hyperpolarization in the closer phase was hardly apparent. This indicates that the closer-phase inhibition occurs predominantly at the posterior dendrite, whereas the opener-phase depolarizations are more pronounced in the anterior dendrites. Recordings from the axon revealed just the rhythmic spike activity of the neuron, which reached 160–200 Hz during the opener phases. In the dendrite of T3-DO, the membrane depolarization coupled to the first syllable of a chirp was slightly less pronounced as compared with the following syllables. Like in the opener-interneuron A3-AO, also in T3-DO we never observed spike activity or any synaptic inputs before or after singing episodes or during the chirp intervals.
When we tried to disturb the ongoing singing activity by electrical stimulation of T3-DO, it became apparent that its main dendrite required exceptionally strong depolarizing current pulses of 10–20 nA to evoke additional spike activity. However, when effectively stimulated, the neuron generated rhythmic membrane potential oscillations for the duration of the current injection (Fig. 6C). During each of the depolarization phases, the neuron produced a burst of 3–5 action potentials, which elicited a cycle of opener–closer motoneuron activity reflecting the syllable pattern of fictive singing. Current pulses of 20 nA amplitude and just 20 msec duration were sufficient to evoke a single syllable, current pulses of 500 msec released 10–12 syllables, and sustained current injection for 1 sec caused a continuous train of 20–25 syllables. Similar to the reset effect of A3-AO, the additional syllables elicited by current injection in T3-DO reset the chirp rhythm in a way that after stimulation the next chirp cycle always started with a normal chirp interval of 180–250 msec (Fig. 6D). The current injection experiments demonstrated that depolarizing T3-DO beyond its spiking threshold is sufficient to drive the syllable motor pattern of fictive singing and reset the chirp rhythm.
During fictive singing even strong hyperpolarizing current injection of −20 nA in the main dendrite of T3-DO did not evidently reduce the spike activity of the interneuron, although it clearly reversed the polarity of the inhibitory postsynaptic potentials (IPSPs) in the closer phase. However, elevated T3-DO spike activity of about 100 action potentials per second, which occasionally occurred when the recording electrode entered the dendrite of the neuron, stopped fictive singing immediately (Fig. 6E). Interestingly, the high-frequency spike activity of T3-DO was still organized in bursts of 3–4 spikes, which were separated by brief phases of hyperpolarization. Moreover, the concomitantly occurring large-amplitude motoneuron spikes in the wing nerve were strictly latency coupled to the preceding interneuron burst (latency: 24 ± 2 msec; mean ± SD; N = 1, n = 50). Within a few seconds of recovery after microelectrode penetration, the mean burst frequency of T3-DO gradually decreased to about 10 Hz and the inhibition following each burst became more and more prominent. On subsequent intracellular injection of hyperpolarizing current (−1 nA), the spike bursts of T3-DO became grouped into the normal chirp pattern, and at the same time, the motor output of fictive singing was instantaneously reconstituted (Fig. 6E).
Ascending opener-interneuron A1-AO
We also identified an ascending interneuron in the metathoracic ganglion complex that spiked rhythmically in phase with the wing-opener activity and that was inhibited in phase with the wing-closer motoneurons. Its soma was located at the lateral margin of the first fused abdominal neuromere A1, from where its primary neurite ran dorsally toward the posterior border of the metathoracic neuromere (Fig. 7A). Forming a loop near the ganglion midline, the main neurite sharply bent anteriorly and the ascending axon projected through the ipsilateral connective toward the mesothoracic ganglion. Before leaving the ganglion, the axon gave off a side branch that ramified dorsally in the anterior metathoracic neuromere. Arising from the neurite, the main dendrite of A1-AO formed a dense meshwork of fine branches projecting anteriorly and posteriorly along the dorsal midline of the neuromeres A1 and A2.
During fictive singing, the membrane potential of A1-AO depolarized by 4–8 mV in each opener phase and hyperpolarized by 4–5 mV in phase with the closer-motoneuron activity (Fig. 7B). Every depolarization gave rise to a burst of 3–6 action potentials with an instantaneous spike frequency of 140–180 Hz. During each syllable, A1-AO fired its first spike 7.5 ± 1.1 msec (mean ± SD; N = 1, n = 50) before the first spike of the wing-opener motoneuron activity and 31.2 ± 1.2 msec (mean ± SD; N = 1, n = 50) before the first spike of the wing-closer activity. During the chirp intervals, the neuron spiked tonically at a rate of 100–120 Hz. This tonic background activity might result from a slightly elevated membrane potential due to the microelectrode penetration. Constant hyperpolarizing current injection in the dendrite of A1-AO completely prevented tonic spiking during the chirp intervals and also reduced the rhythmic spike activity during chirps (Fig. 7C). The spike activity reduction in A1-AO did not affect the singing motor pattern and neither strong depolarizing nor hyperpolarizing current pulses reset the chirp rhythm of fictive singing.
Closer interneurons
While recording in the abdominal neuromeres, we encountered considerably more often opener interneurons than closer interneurons. Nevertheless, in 12 crickets, we recorded interneurons whose rhythmic spike activity was strictly coupled to the closer phase of fictive singing. Here, we describe one morphologically identified closer interneuron and report on functional significant data from two closer interneurons, which were not labeled.
A1-LC is a local closer interneuron in the A1 neuromere of the metathoracic ganglion (Fig. 8A). Its dorsal cell body was located near the ganglion midline and its primary neurite projected toward the contralateral ganglion side. An anterior and a posterior dendritic main branch arose from the primary neurite at the midline of the ganglion and ramified along the dorsal midline of A1 and A2 where they spatially overlapped with the posterior dendrite of T3-DO and axonal branches of A3-AO and T3-DO. During fictive singing, A1-LC was depolarized and generated 2–4 action potentials in each wing-closer phase and was inhibited during the wing-opener phase (Fig. 8B). For each syllable, the neuron fired its first spike 11.4 ± 1.5 msec (mean ± SD; N = 1, n = 20) after the first wing-opener motoneuron spike and 10.2 ± 1.1 msec (mean ± SD; N = 1, n = 20) before the first spike of the wing-closer burst. During the chirp intervals, the membrane potential of A1-LC was up to 3 mV below the resting potential, which drastically reduced its spontaneous spike activity from 23 Hz before and after singing episodes to a mean spike activity of 8 Hz during chirp intervals.
In the A2 neuromere, we recorded a morphologically unidentified closer interneuron that received conspicuous inhibition at the beginning of each chirp and indicated postinhibitory rebound as a presumable mechanism contributing to singing pattern generation. During fictive singing, this closer neuron was inhibited in each opener phase and depolarized by 20–25 mV in the closer phase (Fig. 9A). Every depolarization gave rise to a burst of 5–6 action potentials with a spike frequency of 250–300 Hz. During each syllable, the neuron fired its first spike 12.0 ± 2.3 msec (mean ± SD; N = 1, n = 50) after the start of the wing-opener motoneuron burst and 8.0 ± 0.4 msec (mean ± SD; N = 1, n = 50) before the first spike of the wing-closer burst. Injection of depolarizing current pulses (+5 nA; 100 msec) reset the ongoing chirp rhythm similar to A3-AO and T3-DO, but in contrast to the reset effect of the opener interneurons, electrical stimulation of this closer neuron did not elicit additional singing motor activity (Fig. 9B). Interestingly, during the chirp intervals following the current pulses (arrows in Fig. 9B), the membrane potential was about 3 mV lower as during the preceding and following chirp intervals. Before the start of each singing episode, this closer interneuron received several volleys of 4–6 individual IPSPs at a time (Fig. 9C). After singing started, similar IPSP volleys preceded each chirp, and while the chirp rate increased during the first seconds of a singing episode, the individual IPSPs within each volley started to coincide more and more. When singing was in full swing (Fig. 9A), the membrane potential during the chirp intervals was up to 5 mV below the resting potential, and in addition, every chirp started with a pronounced compound IPSP of up to −5 mV amplitude. More insight into coupling of membrane hyperpolarization and subsequent excitation was provided by spontaneous synaptic activity, as well as hyperpolarizing current injection. After a singing episode, we recorded a continuous train of IPSPs (Fig. 9D). The individual IPSPs had amplitudes between −2 and −5 mV (average: −3.1 mV; N = 1, n = 30; asterisk in Fig. 9D inset), occurred at a rate of 15–20 Hz, and were followed by transient postinhibitory depolarization of 10–20 msec duration and peak amplitudes of 0.3–1.1 mV (average: 0.6 mV; N = 1, n = 30; arrowhead in Fig. 9D inset). Similarly, hyperpolarizing current injection of −2 nA for 500 msec elicited a subsequent rebound depolarization of 4 mV (peak amplitude), which triggered an immediate spike response and rhythmic singing activity starting about 300 msec after the stimulation (Fig. 9D). Short (125 msec) hyperpolarizing current pulses of −4 nA also entailed rebound depolarization that reliably triggered a single spike that was frequently followed by 1–3 IPSPs after 100–200 msec (Fig. 9E). When hyperpolarizing pulses (−4 nA; 125 msec) were injected repetitively at 2 Hz, corresponding to a slow chirp rate, they eventually triggered brief episodes of rhythmic membrane potential oscillation accompanied by singing motor activity. To quantify the relation between hyperpolarization and subsequent rebound depolarization, the closer interneuron was stimulated with hyperpolarizing current pulses of different amplitudes but with a constant duration of 125 msec. No depolarization or spike response occurred after stimulation with −1 nA (N = 1, n = 5), whereas pulses of −3 nA (N = 1, n = 5) evoked 1–3 mV poststimulus depolarizations that occasionally triggered a single action potential. Current pulses of −4 nA (N = 1, n = 5) elicited rebound depolarizations of 2–4 mV that reliably triggered 1–2 spikes (see average responses in Fig. 9F). The post-hyperpolarization spike response was frequently accompanied by consecutive IPSPs occurring after 100–300 msec (Fig. 9E).
In another cricket, a recording from the dendrite of a closer interneuron in the unfused abdominal ganglion A3 (data not shown) showed very similar characteristics. This closer neuron also received a volley of 4–6 IPSPs immediately before each singing episode and transient hyperpolarizing current injection (−0.5 nA) in the dendrite of the neuron triggered enduring singing activity with the normal chirp pattern. During the first chirps of a singing episode, its overall membrane potential slowly hyperpolarized and after singing stopped it repolarized within 3–5 sec to the resting potential. During singing, the neuron hyperpolarized by 5–10 mV in phase with the opener-motoneuron activity and depolarized by 10–15 mV in phase with the closer motoneurons. Each depolarization gave rise to a burst of 2–4 action potentials starting 9.3 ± 0.9 msec (mean ± SD; N = 1, n = 50) after the beginning of the wing-opener activity and 14.3 ± 0.9 msec (mean ± SD; N = 1, n = 50) before the wing-closer activity, which is 4–6 msec earlier than the closer neurons we recorded in the abdominal neuromeres of the metathoracic ganglion.
The neural basis of cricket singing has been repeatedly the subject of neurobiological studies (reviews: Kutsch and Huber 1989; Elsner 1994; Gerhardt and Huber 2002). Here, we intracellularly recorded and stained interneurons of the singing network and demonstrated their impact on singing pattern generation by intracellular current injection.
Motor pattern of fictive singing
After cutting all wing nerves, fictive singing was evoked by microinjection of eserine in the brain neuropiles housing the dendrites of the descending calling song command neurons (Hedwig 2000). With a syllable cycle of 21–26 Hz and a chirp cycle of 2.3–2.9 Hz, the fictive singing motor pattern precisely matched the temporal characteristics of the natural calling song (Doherty 1985; Verburgt et al. 2011). Even minute details like the gradual decrease in the instantaneous syllable rate within the chirps and the constant temporal coupling between wing-opener and wing-closer activity (Kutsch 1969) remained unchanged after deafferentation. This clearly demonstrates that in contrast to locomotory pattern generators (Pearson 1995; Ausborn et al. 2007; Büschges and Gruhn 2008), the cricket singing CPG operates independent of sensory feedback to produce a characteristic and highly stable motor pattern, as required for species-specific signaling. Also in intact crickets, the circuitry of the singing network dictates the temporal pattern of the calling song, whereas mechanosensory feedback merely adjusts the precise angular position and closing velocity of the moving wings (Möss 1971; Elliott 1983; Schäffner and Koch 1987) to ensure a proper engaging force for sound production (Elliott and Koch 1983).
Organization of the singing network
All singing interneurons we identified exhibited characteristic arborizations in the dorsal midline neuropiles of the fused metathoracic and first unfused abdominal ganglion (Fig. 10; Table 1). Likewise, previously identified singing interneurons had dendrites projecting posteriorly along the midline of the metathoracic ganglion complex (Hennig 1990). This local clustering of intermeshing singing interneuron arborizations clearly indicates the dorsal midline neuropiles of the metathoracic and three most anterior abdominal neuromeres as the location of singing pattern generation. Initially the CPG was thought to be located in the mesothoracic ganglion, which houses the singing motoneurons (Kutsch 1969; Kutsch and Otto 1972; Hoy 1978). Our data, however, now confirm at the cellular level the previously indicated spatial separation between the ganglion that generates the final motor output and the ganglia housing the CPG (Hennig and Otto 1995; Schöneich and Hedwig 2011) by revealing crucial CPG interneurons in A3, which had not been described in detail before.
|Number of specimen recorded/stained
|Action potentials per syllable
|Interneuron spike delay… (mean ± SD in msec)
|Reset of the chirp rhythm
|Opener INs
|…to wing-opener motoneurons
|7.0 ± 0.8
|7.5 ± 1.1
|10.1 ± 0.8
|Closer INs
|…to wing-closer motoneurons
|10.2 ± 1.1
|cIN in A2
|8.0 ± 0.4
|cIN in A3
|14.3 ± 0.9
In grasshoppers, which use their hind legs for sound production, singing interneurons with reset properties also have characteristic medial arborizations in the dorsal neuropile of the metathoracic–abdominal ganglion complex (Gramoll and Elsner 1987; Hedwig 1992; Schütze and Elsner 2001). Despite the use of different thoracic appendages (hind legs vs. front wings), in grasshoppers as well as in crickets, the singing network extends over the same neuromeres (T3 and A1–A3). Also in Drosophila, typical wing vibrations of male courtship singing can be elicited by stimulation of specific thoracic–abdominal interneurons (Clyne and Miesenböck 2008; von Philipsborn et al. 2011) and in arctiid moths that use tymbals for rhythmic sound production, the motor pattern is generated in the thoracic–abdominal ganglion complex as well (Dawson and Fullard 1995). This suggests that the circuits for intraspecific acoustic signaling have a common evolutionary origin based on early thoracic–abdominal motor control networks, which may have been linked to ventilation (cf. Robertson et al. 1982; Dumont and Robertson 1986).
Interestingly, the morphology of T3-DO in the metathoracic ganglion as well as its descending axon with projections in every unfused abdominal ganglion resembles the ventilation-coordinating interneurons identified in locusts (Pearson 1980; Ramirez and Pearson 1989). Considering that in a singing cricket, the abdominal ventilation cycles are strictly coupled to the chirp rhythm (Paripovic et al. 1996), the axonal projections of T3-DO in the posterior abdominal ganglia could link the singing CPG output to the abdominal ventilatory oscillators (Kammer 1976; Ramirez and Pearson 1989).
Cellular organization of the singing CPG
In accordance with other studies (Robertson and Pearson 1983; Ramirez and Pearson 1989; Jürgens and Hage 2007), we only considered an interneuron to be part of the singing CPG if its rhythmic spike discharge strictly preceded the motor activity, and if transient perturbation of its activity reset the fictive singing pattern. In terms of these criteria, the opener-interneuron A3-AO and T3-DO and the closer interneurons recorded in A2 and A3 qualify as components of the singing CPG.
The ascending and descending opener-interneuron A3-AO and T3-DO occurred both as pairs of bilateral mirror-image sibling cells, and in both cases, intracellular depolarizing current injection in either the right or left interneuron was sufficient to elicit singing motor activity. If the singing CPG consists of bilateral-symmetrical hemioscillators (Ronacher 1989; Hennig and Otto 1995), at some point the left and right subcircuits need to be coupled to ensure coordinated movement of the two forewings for sound production. A common mechanism for synchronizing CPG neurons is electrical coupling via gap junctions (Marder and Calabrese 1996; Kiehn and Tresch 2002), which is often indicated by dye coupling (Ewadinger et al. 1994; Antonsen and Edwards 2003; Fan et al. 2005). Labeling an A3-AO with neurobiotin reliably stained the contralateral A3-AO sibling neuron as well, whereas for T3-DO even intense neurobiotin labeling never indicated any dye coupling. This points toward electrical synapses between the A3-AO sibling cells providing bilateral synchronization of the motor pattern. Besides graded synaptic transmission (Simmons 1982; Manor et al. 1997), electrical coupling would explain how subthreshold shifting of the A3-AO membrane potential modulated the singing rhythm (cf. Mulloney et al. 1981; Mamiya et al. 2003). Similar subthreshold interaction has been reported between flight CPG neurons in the locust (Robertson and Reye 1988).
The spatial overlap of the T3-DO main dendrite with axonal arborization of both A3-AO neurons and vice versa (Fig. 10) indicate mutual synaptic connections between these CPG neurons. As spike activity in the ascending A3-AO neurons strictly preceded the first T3-DO spike by about 3 msec, the depolarization of T3-DO could be driven by excitatory A3-AO inputs, whereas the depolarization of A3-AO cannot primarily result from descending T3-DO inputs and may involve the descending command neurons.
Some flight CPG interneurons directly activate motoneurons (Robertson and Pearson 1985). As mesothoracic and prothoracic motoneurons contribute to singing (Kutsch 1969; Pfau and Koch 1994), the meso- and prothoracic axon collaterals of A3-AO may allow such direct connections. The opener-inter neuron A1-AO forward the rhythmic CPG output from the metathoracic ganglion to the mesothoracic motor network without interfering with pattern generation.
Generation of syllable and chirp rhythm
Our experiments clearly indicate A3-AO and T3-DO as crucial elements of the syllable–rhythm-generating network (cf. Figs. 2C–E and 6C–E). The membrane potential oscillations in A3-AO and T3-DO seem to result from excitatory inputs as well as inhibitory connections with yet unidentified closer interneurons like those we recorded in the anterior abdominal neuromeres. Besides the ability to reset the singing motor pattern, the closer interneuron we recorded in A2 (Fig. 9) received substantial inhibition in the opener phase and also exhibited postinhibitory rebound depolarization. Mutual inhibiting interneurons that respond with postinhibitory rebound generate rhythmically alternating activity bursts (Perkel and Mulloney 1974; Satterlie 1985). Our data indicate that rebound from opener-phase inhibition triggers closer-interneuron spiking, which in turn temporarily inhibit opener interneurons during the closer phase. This would explain the tight latency coupling of wing-opener and wing-closer bursts in the motor pattern (Kutsch and Huber 1989). Only opener interneurons (e.g., A3-AO) showed small subthreshold depolarizations following the last syllable cycle of the chirps, whereas in closer interneurons the depolarization of the last syllable in the chirp slowly decayed (e.g., Fig. 9A). This suggests that once a chirp has started, the alternate bursting of opener and closer interneurons continues until the opener neurons finally fail to generate a spike burst.
Activated by tonic command neuron spike activity, the singing CPG generates the species-specific calling song pattern with 3–5 syllables grouped to chirps. Constant depolarizing current injection in A3-AO or T3-DO, however, elicited sustained syllable trains, which reliably reset the ongoing chirp rhythm. Subsequent to current elicited syllables, the next chirp always started after a regular chirp interval. This result contradicts the idea of an independent chirp-cycle generator that periodically drives or inhibits the syllable generating circuit (Kutsch 1969; Bentley 1969). The chirp rhythm rather originates from activity-dependent inherent network and/or cellular properties (Bentley and Hoy 1972) that regularly silence the syllable generation and let it recover after a normal chirp interval. Additionally, the chirp pattern is stabilized by rhythmic feedback loops comprising interneurons of the subesophageal and posterior abdominal ganglia (Otto and Hennig 1993; Schöneich and Hedwig 2011) and also depends on the activity level of the descending command neurons (Hedwig 2000). Further studies are required to reveal the neural mechanism controlling chirp generation, which probably include activity-dependent slow changes of membrane conductances (El Manira et al. 1994; Harris-Warrick 2010) and/or periodical recovery of strongly depressing synapses (Manor and Nadim 2001).
Future prospects
Our identification of singing CPG neurons in Gryllus bimaculatus highlights the importance of ganglion A3. The data provide the basis for further studies to establish the functional circuitry of the network and to reveal evolutionary modifications in the singing CPG that account for the distinctive calling song patterns in related cricket species (Alexander 1962). Moreover, the connection between the singing CPG and the corollary discharge interneuron that modulates auditory processing during sound production (Poulet and Hedwig 2002, 2006) may now be targeted.
As gene expression studies considerably benefit from better knowledge about where in the nervous system the relevant phenotypic differentiations are most likely to occur (Shaw and Danley 2003), our results will also contribute to research efforts to obtain a genic understanding of speciation in crickets (Ellison et al. 2011) and also other acoustically communicating insects such as Drosophila (Rideout et al. 2007; von Philipsborn et al. 2011).
Conflict of Interest
The authors declare that there is no conflict of interest.
Role of authors: All authors had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: B. H., S. S. Acquisition of data: S. S. Analysis and interpretation of data: S. S., B. H. Drafting of the manuscript: S. S., B. H. Administrative, technical, and material support: B. H., S. S. Obtained funding: B. H.
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Location and breakfast are excellent but the owners, Brian and Josephine, are truly extraordinary. Helpful, knowledgeable, entertaining, willing to go the extra mile. They really make the experience and we will be back.
Bathroom for downstairs apartment a bit small. But then again, for no upcharge owners let us stay in huge apartment downstairs -- including breakfast -- so I wouldn't have to climb stairs on my bad knee. Really the nicest people and we so enjoyed them.
Too noisy. Also I book on kayak however the hotel never received the reservation and no record of the confirmation number.
The proximity to the beach and the staff was friendly.
The bathroom didn't have a fan. Room looked like something out of the 1970's and smelled like it to. Check-in was late after 4:00. I would never stay there again.
Not to regular hotel standards, no appeal.
Room was small and staff was not very friendly.
Very clean and they allowed our dog. The room was more than we had expected base on the star rating
The location was perfect. It was close to the beach and close to restaurants and bars for the evening. The staff was extremely helpful and friendly.
Great location!
very close to the main strip and shopping
the room was very small. we had to stand still in order to get past each other. water smelled due to being on a well system.
the water stopped working ... the water was also bad, they need a fiter
Price, my stay was in late September.
The location was very good.
Very few television channels, and I read all the fine print, after I signed to agree to it and there are a whole lot of conditions to be met or a stay could turn out to be VERY costly. And I did not read where a unsatisfied customer can get their money back.
Here's why:
We're not the seller
At KAYAK we don't set prices, so it's not possible for us to guarantee what other companies are selling.
We aggregate tons of data for you
Our service lets you quickly and easily compare results from hundreds of travel sites at once. In this sense, KAYAK is a search engine and we don't guarantee prices we find.
Why aren't prices accurate 100% of the time?
Prices on airline seats, hotel rooms and car rentals can change frequently. Several people may also be trying to buy the same travel option simultaneously. As a result, you may find on occasion that certain prices are no longer available.
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subset: commoncrawl


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The Lindt Chocolate Cafe in Sydney was taken hostage by an Islamist terrorist named Haron Monis. Watch terrified people flee the scene past the military.
After telling his parents he was going on a fishing trip and never returning, Abdullah Elmir, 17, now calling himself Abu Khaled, has surfaced in an ISIS video.
The Australian rugby star quit the sport to pursue his dream of playing in the NFL. He is searching for a team that will sign him.
An ISIS cell's plan to behead a member of the public in Sydney and Brisbane was thwarted by anti-terror police. Here's the info on the Islamic State in Oz.
Lindsay Price is married to Top Chef Duels host Curtis Stone. The 37-year-old is expecting her second child with the celebrity chef.
See Arjen Robben's goal to open the scoring in the World Cup match of Australia vs. Netherlands.
Australia meets The Netherlands in a crucial Group B matchup in World Cup 2014. See all the key highlights, photos and videos.
Australia's slim hopes of advancing to the World Cup Round of 16 are on the line today against the Netherlands, and we've got all the game's best photos.


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Colin's Column | Italy's Cultural, Creative and Intellectual Continuum
As London's Victoria and Albert Museum unveils "The Glamour of Italian Fashion," Colin McDowell explores the country's rich fashion history.
As London's Victoria and Albert Museum unveils "The Glamour of Italian Fashion," Colin McDowell explores the country's rich fashion history.
Technology will replace products, brands and financial strategies as the key source of value creation for fashion companies, argues Enrico Beltramini.
The April 2014 cover of American Vogue, featuring Kanye West and Kim Kardashian, proves that media now belongs to the people — but Vogue is not dead, writes Bonnie Morrison.
Given the intertwined beauty and troubled complexity of the lives of Yves Saint Laurent and his lover and business partner Pierre Bergé, Jalil Lespert's biopic should have been much more interesting than it is, reports Colin McDowell.
In today's reality, retailers who fail to embrace omni-channel strategies powered by connected data risk becoming extinct, argues John Squire.
Colin McDowell sits down with Mandi Lennard, a PR turned brand consultant who has built a unique position for herself at the intersection of emerging culture and London's fashion scene.
Debra Scherer speaks to Amy Odell, editor of Cosmopolitan.com, about what she learned working at The Cut and BuzzFeed, her goals for Cosmo's online presence, and the state of fashion media in the Internet Age.
In the Internet Age, fashion consumers increasingly know what they want long before they visit retailers, undermining the traditional role of department stores and boutiques as curators of style, argues Eugene Rabkin.
BoF founder and editor-in-chief Imran Amed looks back at the Autumn/Winter 2014 season.
In the iPhone Age, fashion week has become one glorified, ridiculous, narcissistic, nauseating selfie, argues Mark C. O'Flaherty.
Despite the rise of e-commerce, offline retail remains a fantastic opportunity for fashion brands, while offering features that digital channels will simply never be able to duplicate, argues Ari Bloom.
The problem with fashion criticism isn't the lack of honest opinion, but the lack of places to publish it, argues Jason Dike.
Colin McDowell speaks to Diane Pernet, the perennially black-clad former designer and journalist, who was one of the world's first fashion bloggers and a pioneer of fashion film.


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A successful outfit relies upon a solid foundation, which is why many women wear quality lingerie and avoid stilettoes with banana peels stuck on their bottoms. Build an unshakable image with this Groupon.
Choose Between Two Options
- $30 for $60 worth of lingerie, sleepwear, and swimwear
- $45 for $100 worth of lingerie, sleepwear, and swimwear
Online shelves brim with apparel that costs $39.95 per piece, including a Marilyn lingerie set, a Samantha swimsuit, a Dana satin robe, a Jenny corset, and a package of three Backseam stockings.
"Good variety of clothing Be aware about details of VIP club and required purchases so you are not charged monthly fee"


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Heating and cooling a room addition
Right now we have propane for heat and central air but where I want to add my new sewing room it will not be easy to tie in to the present system and the existing system might not be large enough. What would be the best way to heat and cool my new room? I was thinking about the heating in the floor but don't know if that would be enough. Also, I do not want a window type air conditioner. The room is supposed to be 20 feet by 30 feet--at least that is what I want. I would appreciate any help with this.
Sue in Wyoming
Why don't you ask the contractor about the possibilities?
You could use a split systen A/C for the room. It would require a compressor outside and a wall hung unit inside. Heat could be electric baseboard, electric radiant, separate oil fired boiler for hotwater baseboard or hot water radiant heat. You could also use a geothermal heat pump. Solar?
On the addition over the garage were going with a separate wall hung gas boiler for heat.


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Fascinating, compelling, and more than a little entertaining, Wheat Belly may be the most important health book of the year. --Dana Carpender, author of 500 Low-Carb Recipes
Dr Davis' comprehensive, readable and witty book reveals that wheat, far from being the staff of life, is in fact the stuff of nightmares. Take his advice to lose wheat from your diet and you'll likely be paid back many times over in the form of a slimmer, healthier body and a better functioning brain. --Dr. John Briffa BSc MB BS nutritional physician and author of Waist Disposal
"Davis makes a compelling case" --Fort Worth Star Telegram
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This book is inspiring!! I learned so much from reading it and it motivated me to give up eating wheat. I lost fourteen pounds in a month!! Thank you for writing this book. Read morePublished 2 days ago by Monique Koba
We cannot continue to avoid the fact that the American diet is killing us. This book provides great and easy alternatives to the American diet. Read morePublished 3 days ago by Kristin Bowe
I bought this book because my daughter needs a gluten free diet. But then I began to see some things that applied to me, too. So I started avoiding wheat and wheat products myself. Read morePublished 4 days ago by alice
Never thought of wheat this way. Trying to make the change NOW! ThanksPublished 4 days ago by Judith A Swayze


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Wedding is considered as the best day of every woman in the world. This is the time that she is going to married the man of her dream and for the man; it is the time that he will married the woman who will complete his world.
Talking about weddings is very exciting especially if it is about the wedding preparations. That is the reason why we created this site; we love weddings so much that we are willing to give advises to the couples who are planning their special day.
Before planning for your wedding you should complete all the documents needed for your wedding.
How to plan a wedding? They said it is fun but hard at the same time because of the preparations that you need to do, things that you have to complete, place that you have to coordinate with and talk to the people that are involve.
To be able to prepare your wedding, you should be mentally prepared. You should be open minded and flexible because mostly, the things that you want for your wedding may not be available or the way you imagine it may not work out in real life, so be open to changes. You should also have to compromise your plan with the available budget. Do not be stiff, it is your wedding that you are planning, be happy throughout the process so you can make the right decisions along the way.
The first thing to consider in planning a wedding is the budget. Your choices should be fitted to the budget. Choose something that will go well with your wedding and at the same time would not hurt your budget. Do not let the financial stress take over you. When problems occur you should calm your senses and think wisely about your decisions.
Create a to-do list. This will guide you on what you have to do for your wedding and what are the things that you need to buy for your wedding. Your to-do-list will also help you not to forget anything.
Choose the date for your special day. The date should depend on you, the date can be something special or it is the place where you think everyone is available and they can attend your wedding. Have an alternate date planned because the wedding place or other circumstances may occur and the last resort is just to change the date.
Choose the place for your wedding day and the reception area. This place must be the place that you really want to get married. Talk with your partner and discuss about the place. If you are going with a theme then the place should also fit to your chosen theme. Also consider the weather on the date of your wedding, if you are planning to be married on a rainy season then a beach wedding is not a good idea.
Make a list of the people that you want to be involved in your wedding like your chosen godfather, godmother and the entourage. Talk to those people and ask if they are willing to be part of your wedding. If they are, tell them all the things that they have to know about your wedding and what are their role. They should know the theme wedding and the arrangement on the gowns.
Buy the necessary items for your wedding, the wedding dress, the groom's suit, the rings, the cord, veil, candles and the coins. Now is the time to choose the entourage suits and gowns, the music, the invitation, flowers, centrepiece, photographer, videographer, make-up artist, the caterer, the cake, the wedding car, the arrangement for the wedding place and the reception. Make sure that all the things and arrangement that you choose will go well with your chosen theme.
Do not forget to do follow ups on your orders and to the people involve. Settle all the things needed for your wedding two to three days before your wedding so you will still have time to relax and to spend with your family and friends.
More weddings tips are available in our site and you are very welcome to read it.


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BIDDEFORD, Maine (AP) — A baseball fan took up smoking a century ago and with it acquired another habit: holding onto little cards that bore the faces of baseball's earliest greats.
Now, the trove of more than 1,400 tobacco cards featuring a slew of Hall of Famers like Cy Young and Ty Cobb — the legacy of a teenage smoker whose family hung onto a collection that dates to 1909 — is going up for auction.
The cards will be sold by a Maine auction house that is becoming known for selling rare memorabilia, Saco River Auction Co. in Biddeford.
Troy Thibodeau, the company's manager and auctioneer, said the collection of cards dating from 1909 to 1911 — an era when the Yankees were the Highlanders, the Dodgers were the Superbas and the Braves were the Doves — belongs to the grandchildren of a Brooklyn, New York-born man who began smoking when he was 19.
"Every time he got a card, he threw it in a box," Thibodeau said.
The collection has been dubbed the "Portland trove" because some of the collector's descendants ended up in Maine's largest city. The family doesn't want to be identified, Thibodeau said.
Due to be auctioned individually and in small lots starting in January, the collection includes about 10 cards depicting Young and a dozen depicting Cobb, along with other Hall of Famers like Chief Bender, Christy Mathewson and Walter Johnson.
Smaller than modern baseball cards, these cards known as "T206" cards to collectors feature color lithographs on the front and a tobacco advertisement on the back.
"They're not like your normal baseball card where there's a stock piece of photography that's printed on millions and millions of cards. These are truly pieces of art. They're colorful, they're bright, they're folky, they're Americana," Thibodeau said.
Continue reading this story on the...


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On Palm Sunday, March 29, we will celebrate together at one combined worship service at 10am in the sanctuary, followed by an all-church potluck lunch at 11am. Children who would like to be part of the palm processional during worship should meet in the Worship & Wonder room at 9:45 in order to line up and receive their palm branches.
Author Archives: Phil Snider
Soul Repair: Recovery from Moral Injury After War
On Tuesday, March 31 at 7:30 p.m. in Clara Thompson Hall, the Drury School of Religion will offer Drury and the Springfield area the opportunity to hear Disciples of Christ theologian Rita Nakashima Brock talk about her work with veterans seeking to recover from the trauma of war. Dr. Brock's ministry to veterans fits very well Drury's own commitment to being a military friendly university. We hope this lecture will be beneficial not only to our own student veterans but to veterans and those who care about them throughout the Ozarks.
Love stands stronger than death and violence
Our congregation's latest article for the Center for Diversity and Reconciliation column published by the News-Leader.
For Christians, Ash Wednesday marked the beginning of the season of Lent, a six-week journey preparing Christians for Easter and the hope of the resurrection — a hope which stands as an age-old symbol that love is stronger than all the powers that try to contain it, including the powers of death and violence.
There's no doubt that far too much death and violence takes its toll in our world, so much so that sometimes it feels like all hope is lost. For those who have suffered the sheer brutality and horror of ISIS, for victims of violence in our own community, including Officer Aaron Pearson as well as all of the others in our community whose lives have been affected or even taken far too soon, and for those who feel like their lives are empty and meaningless and don't know if the world needs them anymore, or if it ever did, our hearts break, and we weep.
Sometimes we don't have words for the sadness that overcomes us, and all we can do is hope that, indeed, love is stronger than all the powers that try to contain it.
At the Center for Diversity and Reconciliation, we don't sentimentalize the realities of our world or try to escape into some ideological vault that serves as a buffer for what negatively haunts it. Instead, we try to dig deeply into the root causes of violence and victimization in order to try to help give birth to a better, more humane world.
While we are a faith-based organization, we recognize that this requires a partnership that crosses many historic divides and barriers in order to do the shared work of peacemaking. We know that there isn't any perfect tradition — whether faith-based or not. We are all flawed in one way or another, which is part of what makes us human. At the same time, one of the gifts of being human is that we recognize that another way of being is possible, and it is our responsibility, and desire, to live into it. Together.
If you would like to join us on this journey, whether you consider yourself religious or not, we hope you will do so. There are too many victims of violence in our community and our world. What we need are those with the courage and conviction to be peacemakers in the spirit of Jesus, Gandhi, and King. It isn't easy work, but in the long run it's perhaps the most important of all.
Ash Wednesday service CANCELLED
Ash Wednesday worship — Feb. 18, 6:00pm
Wine into Water – Feb. 6
10 things that the Book of Revelation is… And is not
[Here are Phil's notes from the first Sunday of reflections on the Book of Revelation. Spoiler Alert: Most of the ways that Revelation is interpreted in contemporary culture, such as in the pop-theology of the Left Behind series of books, is hardly the way biblical scholars approach the meaning and significance of the book…]
"What the Book of Revelation Is… And What It Is Not"
1. It is symbolic commentary… It is not literal history
— Revelation is full of rich symbolism, allegory, and metaphor that is connected to events that transpire in history, but should not be confused for literal narrations or descriptions of events exactly as they transpire in history. Originally, the symbols and such helped early Christians make sense of the oppression and persecution they were enduring at the hands of the Roman Empire (an empire sustained by violence), and gave them language to express their hope and belief that the goodness of God would prevail, even though it didn't always seem like that was the case.
2. It is about God acting in history… It is not about God ending history
3. It is about God renewing the world… It is not about God destroying the world
— At the end of Revelation, the New Jerusalem comes down from heaven and restores the world. (This echoes the prayer Jesus taught his followers: "Thy will be done on earth, as it is in heaven.") Revelation's vision tells us that God ultimately destroys evil, but God does not destroy the world.
— Furthermore, contrary to pop-culture "Left Behind" rapture theology, God overcomes evil not through violence (remember, throughout Revelation, it is Rome that is symbolized by violence), but rather, God overcomes violence through the slain Lamb (imagery connected to Jesus, with images of the lamb symbolizing peace, not violence). It is Rome that seeks victory through violence; it is the way of the Lamb (Christ) that opposes such violence. (As the New Testament scholar Barbara Rossing has said, "'For God so loved the world that he gave us his son,' not World War III.")
4. It is set within the context of early Christians in the late first and early second centuries… It is not set in some far off future
— As John writes, "the time is near." The images and symbols that John invokes stand for figures and events that were prominent in his time and place — they are not reserved only for figures and events that will one day emerge in some far off future which he and his listeners would never be part of. Revelation's promise that God's goodness will overcome evil was written for oppressed and marginalized people living under the violence of the Roman Empire. (With that said, part of the beauty of Revelation is that it becomes a book in which oppressed and marginalized people from all ages can find hope and promise. As the philosopher Walter Benjamin once said, "Every moment contains a door through which the messiah can enter.")
5. It is coded communication that makes sense for early Christians familiar with Jewish traditions… It is not a special code that only the lucky few can crack
— Revelation draws on prominent imagery in the biblical texts, especially of the apocalyptic variety (e.g., Daniel and Ezekiel). The symbolism is not intended to conceal meaning, but to reveal meaning, and those familiar with Jewish imagery and traditions are well-equipped at understanding what John is saying. Modern interpreters who take Revelation grossly out of context (with all of their end-time charts and such) rob it of its original symbolic meaning (as will become clear in subsequent weeks). To treat Revelation as some sort of magical code, decipherable only to those with special revelation, is to do it a great disservice.
6. It is connected to well-known apocalyptic and prophetic genres… But it is not a magical crystal ball that predicts the future
— Revelation is commentary on unjust powers and principalities, and it exposes them for what they are. Prophets speak for God in the sense of exposing the truth (i.e., "speaking truth to power"), not predicting the future. As is obvious, those who use the Bible, particularly the Book of Revelation, in order to predict when the world will end have always gotten it wrong (which is why books like "88 Reasons Jesus will return in 1988″ always have to be revised and updated!).
7. It is a word of hope for people oppressed and persecuted by violent powers… It is not a word of comfort for those doing the oppressing and persecuting
— Revelation speaks a strong word of judgment against powers and principalities that violently oppress and exploit. Such powers and principalities are symbolized by the Beast and by Satan. God's goodness judges them and, ultimately, overcomes them.
— Here, the old adage by Reinhold Niebuhr is apropos: "The gospel comforts the afflicted and afflicts the comfortable."
8. It is best heard today with the ears of the oppressed… Not with the ears of those who represent the status quo
— The book of Revelation condemns representatives of the status quo (even including early Christians who turn a blind eye to the violence of Rome). Modern day people often don't want to treat the book for what it is — a radical, unveiled critique of violence and power — because as a culture we are so enamored with violence and power. As such, those living relatively comfortable, affluent lives in the United States (for whom the status quo often works in their favor) frequently wish to soften and avoid the more radical edges of the Book of Revelation.
— For example, the radical Christian revolutionary Thomas Munzer (1489-1525) was quite a fan of Revelation, whereas Bishop Eusebius, a fourth century confidant of Emperor Constantine, expressed major doubts about including it in the Bible.
9. It is set within a particular time and place… Yet its meaning transcends time and place
— While it is set within the context of Roman oppression, its indictment of violence and its word of hope can carry meaning for all people in similar situations down through the ages.
10. It is a book that at first glance can seem difficult to interpret… But with a little background, it's a book that reveals more meaning than it conceals (as we will talk about together in subsequent weeks).
*As mentioned in the previous post on Brentwood's blog that announced this series of reflections on Revelation, Phil is deeply indebted to the scholarly work of Richard Lowery and Barbara Rossing. Those interested in learning more are encouraged to check out their respective books:
"Revelation: Hope for the World in Troubled Times" & "The Rapture Exposed"
The Book of Revelation: Hope for the World in Troubled Times
Phil's new sermon series on Revelation will walk us through a book in the Bible that is often misunderstood and misused, and will help us reflect on how Revelation functioned among its early hearers and how it might — surprisingly perhaps — still have meaning for us today. (Spoiler Alert: Most of the ways that Revelation is interpreted in contemporary culture, such as in the pop-theology of the Left Behind series of books, is hardly the way biblical scholars approach the meaning and significance of the book!)
Feb. 1 – "What Revelation Is — And What It Is Not"
Feb. 8 – "What the Symbolism in Revelation Means — And What It Does Not" part I
Feb. 15 – "What the Symbolism in Revelation Means — And What It Does Not" part II
Interested in learning more?
Some excellent books Phil has used in prepping for this series include:
Revelation (Covenant Bible Studies) by Richard Lowery
The Rapture Exposed by Barbara Rossing
And here's a great intro illustration by Quaker theologian, C. Wess Daniels:
Phil's latest News-Leader Column: Honor Dr. King by fixing societal structures
Phil's latest Springfield News-Leader column…
As each year goes by, I'm experiencing more and more mixed feelings when celebrating Martin Luther King Jr. Day.
It's not that I think Americans shouldn't take time to honor the legacy of Dr. King. After all, I believe Dr. King is the greatest Christian theologian in our nation's history.
And it's not that I think we shouldn't have a national holiday in his honor. We have a variety of national holidays, and one of the primary things Dr. King left us with is a legacy of non-violent resistance (deeply rooted in, but not confined to, the example of Jesus), and it's vitally important for us as a nation to remember the virtues of non-violence, especially when we so frequently rush to arms and valorize warfare.
Every year my church and my family march with hundreds of others in the Springfield area out of a shared commitment to justice, dignity and equality, and I wish to continue these practices well into the future. Indeed, I want to see them grow.
So why am I experiencing such mixed feelings?
Part of it, I fear, has to do with the way our nation frequently runs the risk of trivializing the deep import of Dr. King's memory and message — a trivialization that harbors the potential of distracting us from the true — and much more difficult — pursuit of justice and equality.
During the Martin Luther King Jr. holiday weekend, we hear a lot of quotes on television and social media related to how everyone — no matter their background, race, or class — is created equally and therefore should be treated with dignity. Which is no doubt true. And we celebrate the beautiful call in Dr. King's "I Have a Dream" speech, reminding ourselves that our treatment of another person should be based on the content of their character and not on the color of their skin. Something else that is no doubt true.
But what we don't hear much about are Dr. King's penetrating critiques of societal structures that systematically take advantage of people — structures that produce unfair playing fields in which a person — no matter how good the content of their interpersonal character may or may not be — doesn't always share in the same advantages that others might have, whether related to education, business, safety, or economic security (this is why racism is always about far more than personal prejudice — it's also about systems of power that are set up to benefit some at the expense of others).
When Dr. King retold the biblical parable of the Good Samaritan, he certainly highlighted the importance of the Good Samaritan helping the man who was robbed, beaten, and left for dead along the Jericho Road. But he didn't limit his analysis to the interpersonal virtues of the Good Samaritan. He went on to say that:
"A true [transformation] of values will cause us to question the fairness of many of our policies. On the one hand, we're called to play the Good Samaritan on life's roadside, but that will be only an initial act. One day we must come to see that the whole Jericho Road must be transformed so that men and women will not be constantly beaten and robbed as they make their journey on life's highway."
Even though segregation and inequality are actually on the rise in America, we're conditioned to believe that to talk about systemic racism is no longer necessary in our so-called "post-racial America." After all, doesn't our annual celebration of Dr. King prove that we've arrived? That justice and equality have been achieved? Hardly.
It's far too easy for us to neglect the full import of Dr. King's legacy — a legacy that many white Americans like myself wish to conveniently repress or ignore. But when we reduce his legacy only to how we treat one another in interpersonal exchanges, and don't pay attention to the way systems of power can be structured in unfair ways that prevent everyone from getting a fair shake, we don't truly honor the man or the message. In such cases, we prefer celebrating the parts of his legacy that don't challenge or push us out of our comfort zones.
If we really wish to honor Dr. King, we must look at the way systemic injustice is structured and brokered in a society in which too many people are left hurt and abandoned along the Jericho Roads of our world. This is no easy task. But it's precisely what Dr. King did. It's also what got him killed.
Do we truly have the courage to pick up where Dr. King left off? Or is the weight of pursuing true justice — and liberty for all — more than we can handle?
Annual Martin Luther King Day March — Jan. 19th
"Human progress is neither automatic nor inevitable… Every step toward the goal of justice requires sacrifice, suffering, and struggle; the tireless exertions and passionate concern of dedicated individuals." — Martin Luther King Jr.
We encourage you to honor the legacy of Dr. King — and reflect on how you might participate in the ongoing work of justice in our world — by taking part in the annual Martin Luther King, Jr. March, on Monday, January 19. The march will begin at 9:30 a.m. at Mediacom Ice Park, 635 E. Trafficway, and end at the Gillioz Theater, 325 Park Central Square. A program dedicated to the historic pursuit of justice will follow.


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SOCIAL SECURITY Q&A: How to maximize your retirement amount
Q. I turn 65 on March 7, 2015. To maximize my retirement amount and not start early, should I start benefits for March or April?
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Joliet News
Local news for Joliet, IL continually updated from thousands of sources on the web.
New Chevy SUVs leading the pack at Chevrolet of Naperville
1 hr ago | Freshnews | Comment?
Body Pulled Out of Des Plaines River Along U S 6
6 hrs ago | WJOL-AM Joliet | Comment?
Toyota of Naperville kicking off tire special on April 1
11 hrs ago | Sys-Con Media | Comment?
Culver's To Hold Fundraisers for Plainfield Fire Families
21 hrs ago | Patch.com | Comment?
Gov Rauner Visits Will County: Says He's Not For Statewide "Right to...
Friday Mar 27 | WJOL-AM Joliet | Comment?
JJC proposes balanced budget for next fiscal year
Friday Mar 27 | Morris Daily Herald | 1
Why Do You Think The German Co-Pilot Crashed The Plane ...
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25 Sexy Celeb Women And Their Tiny Tattoos
Fed Judge Strikes Down California's 10-Day Gun Waiting ...
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Classic Albums Live Performs Pink Floyd-Dark Side Of The Moon
Friday Mar 27 | Patch.com | Comment?
James Van Praagh
Thursday Mar 26 | Patch.com | Comment?
Shorewood Sex Offender Worked as Volunteer With Joliet Ravens Youth Football: Cops
Thursday Mar 26 | Patch.com | Comment?
New Caregiver Guide Helps Battle Against Dementia
Tuesday Mar 24 | BroadwayWorld.com | Comment?
JTHS Students Speak to State Legislators at CTE Legislative Day
Tuesday Mar 24 | Patch.com | Comment?
Elizabeth Blatt
Tuesday Mar 24 | Free Press | Comment?
Angelo Aggelopoulos
Tuesday Mar 24 | Free Press | Comment?
Dwight Rotary hears presentation on Illiana expressway development
Monday Mar 23 | Morris Daily Herald | Comment?
Neighbors Rally To Help Plainfield Family After House Fire
Monday Mar 23 | Patch.com | Comment?
Two drivers charged with DUI after crash that killed pedestrian in Joliet
Monday Mar 23 | WLS-AM Chicago | Comment?
Foodie 5K expanding in 2nd year
Sunday Mar 22 | Kane Co. Chronicle | Comment?
Updated: Mon Mar 30, 2015 04:00 pm
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