Davide Bolchini, Diego Pulido, Anthony Faiola
Prototyping is widely recognized as an effective method for quickly generating cost-effective designs and efficiently gaining user feedback early in the product life cycle [1, 2]. Over the past decade, the method has also been adapted and extensively used for mobile interfaces and devices . Because the design of handheld devices (e.g., PDAs and cell phones) involves complex software functionality as well as a need to be integrated with the customized controls and interaction of the physical device, it requires hardware and software prototyping that is challenging. Celine Pering argues that one of the greatest issues of prototyping is to be efficient with the full range of tools, such as paper or high-fidelity prototypes . For interaction designers to overcome a range of prototyping challenges, they first must recognize that each new and greater level of functionality in prototype development means more implementation time. This article introduces a hybrid method of prototyping that utilizes paper and mobile device technology that is both quick to create and agile to use in the early stages of design without the need to implement a fully operational high-fidelity prototype.
A disadvantage of paper prototypes is that they usually require a facilitator, i.e., someone who has a comprehensive understanding of the application and can adequately demonstrate it to the test participant . In other words, a full interaction experience is limited because the participant relies on the facilitator to provide feedback (e.g., changing paper screens) during the command simulation sequence (e.g., clicking buttons or icons), and to constantly remind the user about how the various elements of the design would eventually fit together in the envisioned product. Without human intervention, the participant is unclear about how the system should respond. On the other hand, paper prototypes do provide a quick means for testing basic interactivity that may be essential for specific design decisions . Tools for agile prototyping and electronic sketching are also increasingly available to support quick design iteration [6, 7].
Conversely, fully interactive high-fidelity prototypes (created with Visual Basic, Flash, HTML, among others) are neither easily nor quickly produced.
Paper prototyping relies on the exclusive use of paper-based artifacts, which are physically detached from the use of any real device or digital interface. High-fidelity prototypes, although difficult to quickly develop, allow test participants to easily enter data and execute commands, while being much less dependent on the facilitator.
Emotion, Design, and Prototyping
When it comes to prototyping and evaluating a mobile touchscreen interface, understanding the emotional response of the user is imperative to better evaluate the quality of design. In particular, not only the appearance of the interface (which can be well anticipated by current prototyping tools and practices), but also the physical holding, feeling, manipulating, and touching of the device are important factors in determining the quality of the user experience . For this reason, standard paper prototypes, though useful and quick to generate, are very limited in delivering the depth of user experience necessary to adequately inform design iteration.
In discussing the relationship of user experience and design, Don Norman states that the “visceral” (or physical) level is the simplest and most primitive cognitive process . With regard to handheld devices, visceral is all about look, feel, and sound, i.e., how a device, including the interface, looks and feels in the hand of the user. The iPhone is one of the greatest examples of the visceral experience. It was designed, in great part, for the visceral level of cognitionApple designed for visual and physical impact. Evaluating the mobile user experience without considering visceral factors is like evaluating the quality of a meal by looking at the menu. A lot can be said about the dishes, but the experience is not there. It is a challenge, of course, to anticipate this experience in early prototyping.
Beyond the visceral experience, the “behavioral” level of cognition is about designing device interaction or behavior to reflect human behavior . In other words, device design becomes intuitive in the way it complements one’s implicit assumptions about how it might work. Last, to design for the “reflective” level of cognition is to appeal to one’s aesthetic sensibilities, uniqueness, and cultural preferences . From such a design perspective, people relate to and acquire a personal adherence to a device as part of their identity and self-expression.
Understanding these three levels of cognition is extremely relevant, because emotional engagement at every level strongly influences human-interface interaction from a physical, aesthetic, and usability perspective. Moreover, if we need to take into account these emotion-centric factors early on in the life-cycle of device design, it is clear that paper prototyping cannot deliver the necessary insight into a full visceral and behavioral experience of the interface in the context of handling the physical device. In other words, if we only use paper separate from its actual relationship to the physical device, we may bypass important elements of the user’s emotional experience. As a consequence, inadequacies of this kind may lead to highly artificial (and ultimately irrelevant) evaluation results. To date, producing high-fidelity electronic prototypes or beta-version releases appear to be the only viable way to have users test or try out mobile applications on their devices. We, however, recommend another intermediate solution.
If we could anticipate the mobile user experience (testing the interface with a device), yet spend minimal effort in implementing high-fidelity prototypes, we would have found a far more efficient way to prototype mobile applications with a much higher ROI in time, energy, and valuable user feedback.
So, how can we arrive at a prototyping technique that can deliver development speed, with both visceral and behavioral user experiences that far exceed the use of paper, but without the need to develop high-fidelity prototypes?
Anticipating the Mobile Experience
We propose a simple and straightforward technique: placing the paper prototype inside the device. It is possible to quickly generate a paper prototype (using traditional guidelines and best practices) and efficiently digitalize it in a form suitable for integration and interaction within a mobile device (see page 29). Designers can then ask users to use an actual mobile device (e.g., an iPhone) to try out the prototype, by looking at and flipping through the digitalized papers, thus envisioning a richer mobile experience.
The “paper in screen” approach has important benefits. Users can hold the actual mobile device while interacting with the digitalized paper prototype. And users can interact with the digital prototype in a way that is intimately integrated with the physical experience, thus capturing a fully emotional and true-to-life usage.
The only drawback (to meet the requirements of an “agile” prototype generation) is that the digitalized paper is not fully interactive. The only supported interaction is moving from one screen to another. This sequential navigation can be easily controlled through the most elementary interaction command available on a mobile device (tapping, sliding, flipping, or using a single button). In other words, the papers are not made interactive, but they become interactive on a more generic and basic level through the use of a standard device command. With minimal initial explanation, users point their finger on the actual interface link they need to activate and slide/ flip the screen to move to the next page. The digital paper prototype is still provisional, malleable, thought provoking, and expressive, but at the same it enables the user to experience it within the real mobile device, with all its affordances for an interaction experience that is both tactile and visceral. And all this can be done at a very limited cost.
From Interface to Experience Prototyping
The cost and feasibility of the paper-in-screen approach should be considered in the context of the design life cycle. In a simplified picture of the established practice of interactive application development, iterations often occur between the experience design and interface evaluation (see Figure 2). Paper prototypes typically serve well in this phase; they can cheaply externalize the reification of the design vision into an interface, more or less refined. Paper-based interface prototyping easily lends itself to a subsequent usability evaluation that can be done through various techniques (usability tests, inspections, or walkthrough). Besides the important details of the interface elements, the conceptual flow of the overall navigation and task support can be evaluated. Still, everything is focused solely on the interface as an artificially separate artifact from the overall user experience. After a reasonable number of insightful iterations, low-fidelity paper prototypes are typically improved, refined, and eventually solidified into more interactive, electronic, partially implemented applications that can be integrated as they are into a mobile device for more lively validation and demonstration. This is the stage in which users can actually try out a mobile application using a real device, and designers are able to finally evaluate their user experience. Besides full usability inspection and lab testing, on-the-field observations can be performed, as all the enabling elements of the user experience are there. Using “paper in screen” provides a straight shortcut to make this process much more efficient (see Figure 1).
In just a few minutes a digital version of the paper prototypes can be made available on a mobile device, to be experienced and tested by users and designers. This inexpensive yet rich anticipation of the interface integrated in the device is a form of “experience prototyping” , as the malleability and provisional character of the anticipated situation still embeds some core ingredients of the final, natural experienceusers interacting with the mobile interface while holding the device. A paper-in-screen prototype lends itself to “experience evaluation,” that can be carried outas with fully higher-fidelity interfaces integrated in the devicealso through field observation.
In essence, using paper-in-screen enables designers to reconstruct very early in the life cycle the synthetic aspect of the user experience, which is typically lost in the separationdue to pragmatic purposes and established practicebetween interface design and device integration. Although this separation of concerns (interface and device) is practical and reasonable, the envisioning of the user experience traditionally suffers from the fact that this chasm is not reconciled until an implemented prototype is ready.
Enabling Feedback from Users and Designers
The nature of user feedback enabled by paper-in-screen prototyping needs proper consideration. As we have emphasized its potential of anticipating visceral elements of the mobile user experience, we also acknowledge its limited interactivity, due to the trade-off between cost (time and effort) and prototype refinement. Still, the direct transposition of paper prototypes into digitalized form integrated in a mobile device generates an interesting outcome. In our experience, users interacting with paper-in-screen are surprisingly able to abstract from the limited interactivity of the prototype (as they consider it part of the work in progress) and raise issues on interface labels, content organization, and affordance, using context to provide suggestions for improvement. Interestingly, the elementary, though viscerally engaging, interactivity with the sequence of screens, provides the real-life experiential context not only to focus on the interface usability, but also to facilitate the discussion on the overall utility of the application for realistic mobile scenarios of usage. The provisional and paper-like characteristics of the interface stimulate feedback on information architecture, navigation affordance, underlying business model, content, and requirements (behavioral level). It is clear that only higher-fidelity prototypes with more refined design will elicit other issues concerning, for example graphics, layout, colors, and elements visibility (reflective level).
From this perspective, paper-in-screen can serve well not only traditional user-based evaluation settings, but also expert reviews (heuristics inspection or walkthroughs), and participatory design activities. Experiencing the partial use of the application within the mobile device is helpful to stimulate discussion in the design team, to support individual inspections, or to enable bodystorming (enacting real-life situations of use).
With the increasing demand for mobile applications and their decreasing time to market, we believe that strategies are needed to anticipate the mobile experience in as many aspects as possible and yet meet the time and budget constraints for agile prototype development. The paper-in-screen technique is an innovative proposal to meet this design challenge.
6. DENIM: An Informal Tool For Early Stage Web Site and UI Design, <http://dub.washington.edu:2007/denim/>.
7. Balsamiq Mockups, <http://www.balsamiq.com/products/mock-ups>.
9. Buchenau, M., and F.J. Suri. “Experience Prototyping.” In Proceedings on Designing Interactive Systems: Processes, Practices, Methods, and Techniques. August 17-19, 2000. New York: ACM Press, 424433.
Davide Bolchini is an assistant professor in human-computer interaction at Indiana University, School of Informatics, Indianapolis. Prior to joining IUPUI, he held positions at the University College London, Politecnico di Milano (Italy), and University of Lugano (Switzerland). His research focuses on conceptual design languages for the user experience, usability inspection methods, and user-requirements modeling for Web applications. He is vice president of the Swiss chapter of the Usability Professionals’ Association and teaches graduate courses in usability evaluation and HCI at IUPUI.
Diego Pulido is an interaction designer at Pearson Education in Indianapolis and master’s student in the human-computer interaction program at Indiana University, School of Informatics, Indianapolis (IUPUI).
Anthony Faiola is the executive associate dean of the School of Informatics, Indiana University, Indianapolis (IUPUI). He is also an associate professor and director of the human-computer interaction program. Faiola’s HCI research interests are twofold: First, in the area of crosscultural computer-mediated communication, specifically related to cultural cognitive design and its impact on interaction and information design, as well as the social and cultural influence of “flow experience” on gaming and virtual worlds. Second, related to biomedical informatics, with a focus on health information technology (HIT) design and usability, which aims to contribute to improving its usability and provide the intelligibility of HIT concepts to users through human-centered research.
Sidebar: Applying “Paper in Screen” Prototyping
With respect to traditional paper prototyping, whereaccording to the user’s selectiona different paper screen is shown (within a limited range of possibilities), the screen sequence is predefined and fixed. This requires the facilitator to verbally indicate to the user the nature of the next step in the scenario sequence (“now you can go to the green chart”), but without specifying the label or button to click on. These conditions enable the evaluation of the overall scenarios in terms of utility of content and functionality, fitness with the requirements and user’s needs, navigation flow, and interface understandability.
The cost, in terms of time spent, of transforming a traditional paper prototype into a “paper in screen” prototype is of course proportional to the number of pictures that need to be edited and organized. But about one hour of work is needed for every seven or eight screens.
We have tested the creation and use of “paper in screen” on the iPhone. However, the technique can be applied to any mobile devices enabling interacting (through touch or hardware commands) with a sequential full-screen set of digital pictures.
Based on our experience, here is a summary of the key steps in creating a fully working “paper in screen” prototype:
- Begin by designing the paper prototype itself. This can be done by following existing guidelines and practices on the subject. The paper prototype should result in a number of representative screens designed around key task scenarios.
- To digitalize each paper screen, a good-quality digital photograph (at least 5 megapixels) may be enough. In this case, the shot should zoom in close enough for digital editing later. As an alternative to a digital picture, the paper can be easily scanned and imported for image editing.
- Modify each picture to fit the screen of the mobile device to be used during testing. Any photoediting software can do the job. For example, a picture needs to be resized to 320×480 pixels to fit the screen size of an Apple iPhone.
- Export your resized image as a picture file supported by your mobile device (PNG, JPEG, GIF). Ideally, the image’s borders should merge with those of the device screen.
- Organize the screen images into photo albums or sets, where one album or set corresponds to a specific scenario to be tested, i.e., a salient sequence of screens corresponding to a task or storyboard sequence.
- Upload your photo albums to the mobile device, and the “paper in screen” is ready.
- Explain to the user how to navigate through the images, whether by pressing a “next” button or flicking the photos with a finger sweep. While carrying out each scenario, users can think aloud and articulate comments about the interface and the sequence of screens.
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Electrolysis IGCSE 0620 by Kanayati ®
Clear concise easy understanding of electrolysis chemistry IGCSE 0620
FINALLY MAKE IT SIMPLE AND UNDERSTAND GCSE CHEMISTRY CAMBRIDGE EDEXCEL
Chemistry IGCSE (CIE)
This is a 42 page revision booklet for Chemistry IGCSE exams. It contains everything you need to know for the CIE exam syllabus. I studied fully and only from this booklet and past papers and attained an A* in my chemistry exam. All information was taken from a Cambridge IGCSE Chemistry textbook and was summarised to contain only the information you need to know for the exam along with further explanations and with images from the textbook itself.


About Glass Wool
Glass wool (originally known also as fiberglass) is an insulating material made from fibres of glass arranged using a binder into a texture similar to wool. Glass wool and stone wool are produced from mineral fibres and are therefore often referred to as ‘mineral wools’. Mineral wool is a general name for fiber materials that are formed by spinning or drawing molten minerals. Glass wool is a furnace product of molten glass at a temperature of about 1450 °C.
|Phase at STP||solid|
|Ultimate Tensile Strength||0.02 MPa|
|Young’s Modulus of Elasticity||N/A|
|Melting Point||1227 °C|
|Thermal Conductivity||0.03 W/mK|
|Heat Capacity||840 J/g K|
Composition of Glass Wool
From the melted glass, fibres are spun. This process is based on spinning molten glass in high-speed spinning heads somewhat like the process used to produce cotton candy. During the spinning of the glass fibres, a binding agent is injected. Glass wool is then produced in rolls or in slabs, with different thermal and mechanical properties. It may also be produced as a material that can be sprayed or applied in place, on the surface to be insulated.
Applications of Glass Wool
Applications of glass wool include structural insulation, pipe insulation, filtration and soundproofing. Glass wool is a versatile material that can be used for the insulation of walls, roofs and floors. It can be a loose fill material, blown into attics, or, together with an active binder sprayed on the underside of structures. During the installation of the glass wool, it should be kept dry at all times, since an increase of the moisture content causes a significant increase in thermal conductivity.
Mechanical Properties of Glass Wool
Strength of Glass Wool
In mechanics of materials, the strength of a material is its ability to withstand an applied load without failure or plastic deformation. Strength of materials basically considers the relationship between the external loads applied to a material and the resulting deformation or change in material dimensions. In designing structures and machines, it is important to consider these factors, in order that the material selected will have adequate strength to resist applied loads or forces and retain its original shape.
Strength of a material is its ability to withstand this applied load without failure or plastic deformation. For tensile stress, the capacity of a material or structure to withstand loads tending to elongate is known as ultimate tensile strength (UTS). Yield strength or yield stress is the material property defined as the stress at which a material begins to deform plastically whereas yield point is the point where nonlinear (elastic + plastic) deformation begins. In case of tensional stress of a uniform bar (stress-strain curve), the Hooke’s law describes behaviour of a bar in the elastic region. The Young’s modulus of elasticity is the elastic modulus for tensile and compressive stress in the linear elasticity regime of a uniaxial deformation and is usually assessed by tensile tests.
See also: Strength of Materials
Ultimate Tensile Strength of Glass Wool
Ultimate tensile strength of Glass Wool is 0.02 MPa.
Yield Strength of Glass Wool
Yield strength of Glass Wool is N/A.
Modulus of Elasticity of Glass Wool
The Young’s modulus of elasticity of Glass Wool is N/A.
Hardness of Glass Wool
In materials science, hardness is the ability to withstand surface indentation (localized plastic deformation) and scratching. Brinell hardness test is one of indentation hardness tests, that has been developed for hardness testing. In Brinell tests, a hard, spherical indenter is forced under a specific load into the surface of the metal to be tested.
The Brinell hardness number (HB) is the load divided by the surface area of the indentation. The diameter of the impression is measured with a microscope with a superimposed scale. The Brinell hardness number is computed from the equation:
Brinell hardness of Glass Wool is approximately N/A.
See also: Hardness of Materials
Thermal Properties of Glass Wool
Glass Wool – Melting Point
Melting point of Glass Wool is 1227 °C.
Note that, these points are associated with the standard atmospheric pressure. In general, melting is a phase change of a substance from the solid to the liquid phase. The melting point of a substance is the temperature at which this phase change occurs. The melting point also defines a condition in which the solid and liquid can exist in equilibrium. For various chemical compounds and alloys, it is difficult to define the melting point, since they are usually a mixture of various chemical elements.
Glass Wool – Thermal Conductivity
Thermal conductivity of Glass Wool is 0.03 W/(m·K).
The heat transfer characteristics of a solid material are measured by a property called the thermal conductivity, k (or λ), measured in W/m.K. It is a measure of a substance’s ability to transfer heat through a material by conduction. Note that Fourier’s law applies for all matter, regardless of its state (solid, liquid, or gas), therefore, it is also defined for liquids and gases.
The thermal conductivity of most liquids and solids varies with temperature. For vapors, it also depends upon pressure. In general:
Most materials are very nearly homogeneous, therefore we can usually write k = k (T). Similar definitions are associated with thermal conductivities in the y- and z-directions (ky, kz), but for an isotropic material the thermal conductivity is independent of the direction of transfer, kx = ky = kz = k.
Glass Wool – Specific Heat
Specific heat of Glass Wool is 840 J/g K.
Specific heat, or specific heat capacity, is a property related to internal energy that is very important in thermodynamics. The intensive properties cv and cp are defined for pure, simple compressible substances as partial derivatives of the internal energy u(T, v) and enthalpy h(T, p), respectively:
where the subscripts v and p denote the variables held fixed during differentiation. The properties cv and cp are referred to as specific heats (or heat capacities) because under certain special conditions they relate the temperature change of a system to the amount of energy added by heat transfer. Their SI units are J/kg K or J/mol K.
Properties and prices of other materials


Hot, young, white dwarfs – the super-dense remains of sunlike stars – have atmospheres made essentially of pure hydrogen or pure helium. But these stars’ atmospheres are contaminated by other elements, too – for example, carbon, silicon and iron – known to astronomers as metals. A decades-old space mystery is how the metals came to be in white dwarf atmospheres. And now an international team of astronomers led by Professor Martin Barstow of the University of Leicester in the U.K. say they have solved the mystery. Their solution points to an ominous fate for planet Earth. Professor Barstow said in a press release:
The mystery of the composition of these stars is a problem we have been trying to solve for more than 20 years. It is exciting to realize that they are swallowing up the leftovers from planetary systems, perhaps like our own.
An earlier idea about this material was that it was “levitated” by the intense radiation from deeper layers in the star.
Now the researchers have discovered that many of the stars show signs of contamination by rocky material, the leftovers from a planetary system.
In the new study, researchers surveyed 89 white dwarfs, using the Far Ultraviolet Spectroscopic Explorer to obtain their spectra. In some of the stars, when certain elements are present in the atmosphere, the spectra reveal the chemical fingerprints of carbon, silicon, phosphorous and sulphur. Barstow said:
We found that in stars with polluted atmospheres the ratio of silicon to carbon matched that seen in rocky material, much higher than found in stars or interstellar gas.
The new work indicates that at around one-third of all hot white dwarfs are contaminated in this way, with the debris most likely in the form of rocky minor planet analogues. This implies that a similar proportion of stars like our sun, as well as stars that are a little more massive like Vega and Fomalhaut, build systems containing terrestrial planets.
This work is a form of celestial archaeology where we are studying the ruins of rocky planets and/or their building blocks, following the demise of the main star.
These scientists say that more detailed follow-up work will reveal much about the composition of rocky planets orbiting other stars. The study also points to the ultimate fate of the Earth billions of years from now – ending up as a contamination in the atmosphere of our sun, after it becomes a white dwarf.
Bottom line: A decades-old about how metals came to be in white dwarf atmospheres may be solved. Results of a new study suggest they are swallowing up the leftovers from planetary systems, much like that of our own Earth.


Despite being one of the less well-known ancient civilisation the Phoenicians represent an interesting and underrated influential impact on Western culture. They may not have had a large inland Empire but they were certainly very much in control of the coast and the sea. They were not particularly warlike but relied on trade and Commerce to establish themselves and their influence. For example they had no capital but had two dominant cities of Byblos and Tyre. They lasted from 2500 BC to 539 BC using a system of Kings and automatic monarchs until establishing a republic in Carthage. In terms of land they originated from what we now call modern Lebanon.
Despite their lack of warlike nature they were still able to have an effect on the region. They were renowned as being Traders and merchants but also explorers, sea based, in large ships. They could have made full use of some Oak Beams in their construction, and they were able to bring several new ideas and practices to the Mediterranean and the lands surrounding it. They followed the structure of city-states much the same as ancient Greece who they had a huge influence on. They also provided one of the oldest alphabet to us.
Sadly very little has survived of the Phoenicians in part due to the fact that they did not have a large land-based capital, Instead we have had to rely on Greek, Roman and North African writers from ancient times to give us a piecemeal account of their history. However what we do know suggests that they were able to give Great guidance and leadership 2tocountries around the Mediterranean and help shape the great empires of Carthage, Rome and Greece itself.


The Nov. 14, 2012 article by Humberto Marquez for AlertNet; a Thompson Reuters Foundation Service, provides a context for why Venezuela is so interested in reducing the environmental footprint left by oil production,
Venezuela, a founding member of the Organisation of the Petroleum Exporting Countries (OPEC), extracts close to three million barrels of oil a day and has over two billion barrels of heavy crude oil reserves.
There are six refineries in the South American country that process a total of 1.1 million barrels daily.
Meanwhile, according to OPEC figures, the country consumes 742,000 barrels of different types of fuel daily, of which 300,000 barrels correspond to the gasoline used by more than six million motor vehicles.
The Ministry of the Environment reports that Venezuela is responsible for 0.48 percent of worldwide emissions of greenhouse gases and 0.56 percent of one of these “villains”, carbon dioxide.
Here are a few details about the research they are currently pursuing,
“We are seeking to use nanoparticles of metallic salts, such as iron, nickel or cobalt nitrates, as catalysts in oil-related processes that produce greenhouse gas emissions,” said Sarah Briceño, a researcher at the Centre for Physics at the Venezuelan Institute of Scientific Research (IVIC).
Catalysts are substances used to speed up chemical processes, “and our goal is to develop catalysts adapted to Venezuelan industry that will make it possible to reduce greenhouse gas emissions from activities such as oil refining and fuel consumption by motor vehicles by up to 50 percent,” Briceño told Tierramérica*.
Apparently, they are expecting this research to yield results in 2013 although it’s unclear whether that means laboratory results or practical applications. Interesting article and this is the first time I’ve found an opportunity to post about Venezuela and its nanotechnology efforts.


EPA Moves to Overhaul Obama-Era Coal Ash Disposal Rule
The U.S. Environmental Protection Agency (EPA) is proposing major changes to Obama-era coal ash disposal regulations, seeking to give states and utilities more leeway in how they dispose of coal ash, which can contain highly toxic substances such as arsenic, mercury and lead.
The Scott Pruitt-led agency claims that the proposal, if finalized, can save the utility sector up to $100 million per year in compliance costs.
"Today's coal ash proposal embodies EPA's commitment to our state partners by providing them with the ability to incorporate flexibilities into their coal ash permit programs based on the needs of their states," Pruitt said in a statement Thursday.
Coal ash is one of the largest types of industrial waste generated in the U.S. The nation's coal plants produce 140 million tons of the toxic byproduct annually, and all that gets dumped into open-air pits and surface-waste ponds. Without proper management of these sites, the harmful contaminants can leach out and pollute waterways, ground water, drinking water and the air.
As the EPA's own website points out, the need for federal action to help ensure protective coal ash disposal was highlighted by two large spills: the Kingston Fossil Plant spill in 2008, when 5.4 million cubic yards of coal ash was released from a failed dike into the Emory River channel in Tennessee; and the Duke Energy spill in 2014, when 39,000 tons of coal ash spilled into the Dan River in North Carolina. The two spills "caused widespread environmental and economic damage to nearby waterways and properties," the EPA says.
That led to the Obama administration's 2015 rule set requirements for the safe storage of coal ash for more than 400 coal-fired power plants nationwide. But now, Trump's EPA is proposing to make more than a dozen changes to the regulation to allow "alternative performance standards" for state and federally permitted facilities.
The Washington Post reported that industry officials had lobbied the Trump administration for the rule changes. They said the existing rule causes "significant adverse impacts on coal-fired generation in this country due to the excessive costs of compliance."
Taking their concerns into account, Pruitt said in September it was "appropriate and in the public interest" for the agency to rethink the regulation.
Environmental groups criticized Pruitt's actions, calling it "another present" to coal executives.
"This is another example of Pruitt not caring about science, working families, or clean water, and instead bending over backwards for polluters eager to avoid accountability to the laws that keep our communities and families healthy," Mary Anne Hitt, director of Sierra Club's Beyond Coal campaign, said then.
Ken Kopocis, the former top official in EPA's water office during the Obama administration, told the Post the original rule had taken already industry concerns into account.
"We bent over backwards for industry both in terms of the substance of the rule and in terms of the timing," Kopocis told The Post in September.
He said rolling the rule back further would endanger public health, calling the coal ash pits "ticking time bombs."
The EPA said it will be accepting public comment on this proposal for 45 days after publication in the Federal Register and plans to hold a public hearing to receive additional feedback on the proposal during the public comment period.
The agency also plans to propose additional changes to the rule later this year.


It should worth the investment making our house more efficient. It should also be considered as our contribution for the environment and it is possible to save a lot of money this way. Many people rack up thousands of dollars each year on utility bills due to inefficient usage of resources. It may not be necessary to do a lot of things in one big swoop, but we can certainly make small improvements here and there.
We should do a number of upgrades and perhaps some remodelling to make these changes permanent. If we do things properly, we will see that these costs will be recouped very fast. After all, many things we do to make our home more efficient shouldn’t cost too much money. This is especially true if we know contractors who are able to do things efficiently.
As an example, we can add weather stripping to windows and doors. This would cost us less than $50, but the annual cooling and heating costs could be a few hundred dollars lower. We should also install windows films on windows that face westwards or eastwards; doing this will cost us less than $100, but the overall savings could be three or four times more than that. In addition, intense sunlight could fade our furniture and carpet; so reducing incoming light could bring multiple benefits. These simple investments could be paid off in just a few months.
Instead of using incandescent light bulbs, it is a good idea to use compact fluorescent bulbs. This will help us save on electricity and the bulbs themselves would last much longer. Some storm windows and door models can also help us save on both heating and cooling costs. If our budget is tight, we can make our own storm windows. These windows should be easy to build.
We only need to get some heavy plastic, a few nails and a good amount of thick lumber. Many of us often replace appliances and it is a good idea to choose options and models with low power usages. If we plan to replace the cooling/heating system, attic fan and water heater; it is also important to choose more energy-efficient replacements.
It is a good idea to replace our water heater with either solar water heater or instant water heater. Solar-powered fans are also much more efficient than standard electric fans. Cooling and heating equipments can also be replaced with heat pumps. If we plan to save more money, it is a good to choose timers with programmable zoned system. This allows us to set different temperature ranges in different parts of our house based on unique requirements.
After a few years, we need to replace a toilet. To save water usage, it is a good idea to choose dual flush toilet. When replacing the roof, we should choose metal roof, which is very efficient and much less expensive. To prevent heat loss during winter, we can also install attic foil.
All of these are wonderful ways to help us improve the environment, while reducing utility costs. However, we shouldn’t ignore further cost reduction opportunities, by getting tax breaks and rebates. Utility companies may offer rebates for customers who plan to install energy efficient lights and appliances. In this case, we only need to call the utility company and ask for immediate replacements. Obviously, we need to make sure that we are fully qualified to receive the rebates themselves.
Learn more on best seo services to help boost your online business presence.


Antimicrobial agents are essential components in the treatment of various bacterial infections as they help to kill or prevent the growth of microbes such as bacteria, fungi, and protozoans. Prior to the discovery of antimicrobial agents, treatment options for patients with bacterial infections were limited. For many patients, treatment often resulted in the amputation of limbs or even death. Today, treatment options for bacterial infections typically have a more positive prognosis. Due to the various types of infections presented in patients, it is essential to be able to identify the underlying cause of the infection—whether bacterial or viral—before recommending drug treatments. This will help you identify whether or not an antimicrobial agent would be appropriate and which specific agent would target the infection. In this Assignment, you consider the appropriate use of antimicrobial agents for infections.
- – Review this week’s media presentation on principles of antimicrobial therapy, as well as Chapter 8 of the Arcangelo and Peterson text.
- – Consider the categories of antimicrobial agents.
- – Think about differences between viral and bacterial infections.
- – Reflect on why proper identification of the infection is key to selecting the proper antimicrobial agent.
POST a 2- to 3- page paper that addresses the following:
- – Describe the categories of antimicrobial agents.
- – Describe differences between viral and bacterial infections.
- – Explain why proper identification of viral and bacterial infections is key to selecting the proper antimicrobial agent.
This work should have Introduction and conclusion
– This work should have at 4 to 6 current references (Year 2012 and up)
– Use at least 3 references from class Learning Resources
The following Resources are not acceptable:
2. Cdc.gov- nonhealthcare professionals section
Arcangelo, V. P., Peterson, A. M., Wilbur, V., & Reinhold, J. A. (Eds.). (2017). Pharmacotherapeutics for advanced practice: A practical approach (4th ed.). Ambler, PA: Lippincott Williams & Wilkins.
- Chapter 8, “Principles of Antimicrobial Therapy” (pp. 111-134)
This chapter covers factors that impact the selection of an antimicrobial treatment regimen. It also examines the clinical uses, adverse events, and drug interactions of various antimicrobial agents such as penicillin.
- Chapter 12, “Fungal Infections of the Skin” (pp. 163-196)
This chapter explores the pathophysiology of several fungal infections of the skin as well as related drug treatments and examines the importance of patient education when managing these infections.
- Chapter 14, “Bacterial Infections of the Skin” (pp. 181-196)
This chapter begins by examining causes of bacterial infections. It then explores the importance of selecting an appropriate agent for treating bacterial infections.
- Chapter 32, “Urinary Tract Infection” (pp. 519-526)
This chapter covers drugs used to treat urinary tract infections and identifies special considerations when treating geriatric patients, pediatric patients, and women.
- Chapter 35, “Sexually Transmitted Infections” (pp. 512-535)
This chapter outlines the causes, pathophysiology, and drug treatment of six sexually transmitted infections, including gonorrhea, syphilis, and human papilloma virus infection (HPV). It also examines the importance of selecting the proper agent and monitoring patient response to treatment.
- Chapter 49, “Human Immunodeficiency Virus” (pp. 843-860)
This chapter presents the causes, pathophysiology, diagnostic criteria, and prevention methods for HIV. It also covers various methods of drug treatment and patient factors to consider when selecting, administering, and managing drug treatments.
Krummenacher, I., Cavassini, M., Bugnon, O., & Schneider, M. (2011). An interdisciplinary HIV-adherence program combining motivational interviewing and electronic antiretroviral drug monitoring. AIDS Care, 23(5), 550–561.
This article analyzes medication adherence in HIV patients and examines factors that increase adherence as well as factors that contribute to termination or discontinuation of treatment.
Drugs.com. (2012). Retrieved from http://www.drugs.com/
This website presents a comprehensive review of prescription and over-the-counter drugs including information on common uses and potential side effects. It also provides updates relating to new drugs on the market, support from health professionals, and a drug-drug interactions checker.
Scourfield, A., Waters, L., & Nelson, M. (2011). Drug combinations for HIV: What’s new? Expert Review of Anti-Infective Therapy, 9(11), 1001–1011.
Note: Retrieved from the Walden Library databases.
This article examines current therapies and strategies for treating HIV patients. It also examines factors that impact selection of therapy, including drug interactions, personalization of therapy, costs, management of comorbidities, and patient response.
Laureate Education, Inc. (Executive Producer). (2012). Antimicrobials. Baltimore, MD: Author.
This media presentation outlines principles of antimicrobial therapy
Note: The approximate length of this media piece is 7 minutes.
Mayer, K. H., & Krakower, D. (2012). Antiretroviral medication and HIV prevention: New steps forward and New Questions. Annals of Internal Medicine, 156(4), 312–314.


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