bluuebunny/crossref_metadata_2025 huggingface dataset:
Concerns and Structural Barriers Associated with WIC Participation among WIC‐Eligible Women
Authors: Liu Cindy H. , Liu Heidi
Published: March 2016

Objectives

To examine sociodemographic status, psychosocial concerns, and structural barriers associated with women's participation in the USDA's Women, Infants, and Children (WIC) program among those eligible for the program.

Design and Sample

A total of 1,634 White, African‐American, Hispanic, and Asian/Pacific Islander (A/PI) women from the New York City area completed the Pregnancy Risk Assessment Monitoring System (PRAMS) from 2004 to 2007, a population‐based survey.

Measures

Data on WIC eligibility and participation, sociodemographic details, unintended pregnancy, social support, and structural barriers were evaluated.

Results

Hispanics and Blacks were 4.1 and 2.4 times more likely to participate, respectively, in the WIC program relative to Whites. Mothers reporting unplanned pregnancies, fewer social supports, and more structural barriers (e.g., transportation) were less likely to participate in WIC. Race‐stratified analyses revealed race/ethnic differences in the pattern of barriers; unintended pregnancy and structural problems were barriers associated with WIC participation particularly for A/PI.

Conclusions

WIC‐eligible women with unintended pregnancies and fewer social supports tend to participate in WIC, but those who experience more structural barriers are less likely to participate. A/PI women may face specific challenges to WIC participation. Careful attention is needed to understand the unique attitudes and behaviors in the process of participating in WIC.
Dialogues of Byrd and Sidney: performing incompleteness
Authors: Bank Katie
Published: March 2016

This article offers a reading of Byrd's setting of Sidney's text ‘O you that heare this voice’ from Byrd's 1588 publication Psalms, sonets, and songs of sadness and piety that positions the piece as a practical performance of the negotiation surrounding changes in episteme that unfolded over the seventeenth century. Musical analysis of William Byrd's settings of poetry by Philip Sidney has proven to present significant hermeneutic challenges. This article presents an observation of an anomaly within one of Byrd's settings that echoes many similar challenges Sidney scholars have encountered when analysing the poet and his works on their own. This incongruity in Byrd's setting of Sidney's verse can be read as related to contemporary concern regarding the role of the arts in understanding sense perception, as well as the role of the performer(s) in the creation of musical meaning in late sixteenth‐century England.
Sodomy in Renaissance Bologna
Authors: Dean Trevor
Published: March 2016

Sodomy has been well studied in Renaissance Florence and Venice. This article for the first time examines this sexual crime in another major Italian city, home of an important university, seat of papal government, and venue of an emergent lordship of the Bentivoglio family. The article starts with a full discussion of the thirty‐nine trials in the Bolognese criminal court across the period 1350–1499, focusing on the evolution of the penalized behaviour, of the character of the suspects and victims (age, provenance), and of the penalty (from death by burning to corporal punishment and incarceration) Two exceptional cases are then discussed at length, in order to focus on two particular issues in these trials, namely the use of torture and the probative quality of ill‐repute.
Highly efficient de novo mutant identification in a Sorghum bicolor TILLING population using the ComSeq approach
Authors: Nida Habte , Blum Shula , Zielinski Dina , Srivastava Dhruv A. , Elbaum Rivka , Xin Zhanguo , Erlich Yaniv , Fridman Eyal , Shental Noam
Published: March 2016

Screening large populations for carriers of known or de novo rare single nucleotide polymorphisms (SNPs) is required both in Targeting induced local lesions in genomes (TILLING) experiments in plants and in screening of human populations. We previously suggested an approach that combines the mathematical field of compressed sensing with next‐generation sequencing to allow such large‐scale screening. Based on pooled measurements, this method identifies multiple carriers of heterozygous or homozygous rare alleles while using only a small fraction of resources. Its rigorous mathematical foundations allow scalable and robust detection, and provide error correction and resilience to experimental noise. Here we present a large‐scale experimental demonstration of our computational approach, in which we targeted a TILLING population of 1024 Sorghum bicolor lines to detect carriers of de novo SNPs whose frequency was less than 0.1%, using only 48 pools. Subsequent validation confirmed that all detected lines were indeed carriers of the predicted mutations. This novel approach provides a highly cost‐effective and robust tool for biologists and breeders to allow identification of novel alleles and subsequent functional analysis.
The intestinal cholinergic anti‐inflammatory pathway
Authors: Goverse Gera , Stakenborg Michelle , Matteoli Gianluca
Published: March 2016

The main task of the immune system is to distinguish and respond accordingly to ‘danger’ or ‘non‐danger’ signals. This is of critical importance in the gastrointestinal tract in which immune cells are constantly in contact with food antigens, symbiotic microflora and potential pathogens. This complex mixture of food antigens and symbionts are essential for providing vital nutrients, so they must be tolerated by the intestinal immune system to prevent aberrant inflammation. Therefore, in the gut the balance between immune activation and tolerance should be tightly regulated to maintain intestinal homeostasis and to prevent hypersensitivity to harmless luminal antigens. Loss of this delicate equilibrium can lead to abnormal activation of the intestinal immune system resulting in devastating gastrointestinal disorders such as inflammatory bowel disease (IBD). Recent evidence supports the idea that the central nervous system interacts dynamically via the vagus nerve with the intestinal immune system to modulate inflammation through humoral and neural pathways, using a mechanism also referred to as the intestinal cholinergic anti‐inflammatory pathway. In this review, we will focus on the current understanding of the mechanisms and neuronal circuits involved in the intestinal cholinergic anti‐inflammatory pathway. Further investigation on the crosstalk between the nervous and intestinal immune system will hopefully provide new insights leading to the identification of innovative therapeutic approaches to treat intestinal inflammatory diseases.

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Rescue of protein expression defects may not be enough to abolish the pro‐arrhythmic phenotype of long QT type 2 mutations
Authors: Perry Matthew D. , Ng Chai Ann , Phan Kevin , David Erikka , Steer Kieran , Hunter Mark J. , Mann Stefan A. , Imtiaz Mohammad , Hill Adam P. , Ke Ying , Vandenberg Jamie I.
Published: March 2016

Key points

Most missense long QT syndrome type 2 (LQTS2) mutations result in Kv11.1 channels that show reduced levels of membrane expression.

Pharmacological chaperones that rescue mutant channel expression could have therapeutic potential to reduce the risk of LQTS2‐associated arrhythmias and sudden cardiac death, but only if the mutant Kv11.1 channels function normally (i.e. like WT channels) after membrane expression is restored.

Fewer than half of mutant channels exhibit relatively normal function after rescue by low temperature. The remaining rescued missense mutant Kv11.1 channels have perturbed gating and/or ion selectivity characteristics.

Co‐expression of WT subunits with gating defective missense mutations ameliorates but does not eliminate the functional abnormalities observed for most mutant channels.

For patients with mutations that affect gating in addition to expression, it may be necessary to use a combination therapy to restore both normal function and normal expression of the channel protein.

In the heart, Kv11.1 channels pass the rapid delayed rectifier current (IKr) which plays critical roles in repolarization of the cardiac action potential and in the suppression of arrhythmias caused by premature stimuli. Over 500 inherited mutations in Kv11.1 are known to cause long QT syndrome type 2 (LQTS2), a cardiac electrical disorder associated with an increased risk of life threatening arrhythmias. Most missense mutations in Kv11.1 reduce the amount of channel protein expressed at the membrane and, as a consequence, there has been considerable interest in developing pharmacological agents to rescue the expression of these channels. However, pharmacological chaperones will only have clinical utility if the mutant Kv11.1 channels function normally after membrane expression is restored. The aim of this study was to characterize the gating phenotype for a subset of LQTS2 mutations to assess what proportion of mutations may be suitable for rescue. As an initial screen we used reduced temperature to rescue expression defects of mutant channels expressed in Xenopus laevis oocytes. Over half (∼56%) of Kv11.1 mutants exhibited functional gating defects that either dramatically reduced the amount of current contributing to cardiac action potential repolarization and/or reduced the amount of protective current elicited in response to premature depolarizations. Our data demonstrate that if pharmacological rescue of protein expression defects is going to have clinical utility in the treatment of LQTS2 then it will be important to assess the gating phenotype of LQTS2 mutations before attempting rescue.
Optogenetic and pharmacological evidence that somatostatin‐GABA neurons are important regulators of parasympathetic outflow to the stomach
Authors: Lewin Amanda E. , Vicini Stefano , Richardson Janell , Dretchen Kenneth L. , Gillis Richard A. , Sahibzada Niaz
Published: March 2016

Key points

The dorsal motor nucleus of the vagus (DMV) in the brainstem consists primarily of vagal preganglionic neurons that innervate postganglionic neurons of the upper gastrointestinal tract.

The activity of the vagal preganglionic neurons is predominantly regulated by GABAergic transmission in the DMV.

The present findings indicate that the overwhelming GABAergic drive present at the DMV is primarily from somatostatin positive GABA (Sst‐GABA) DMV neurons.

Activation of both melanocortin and μ‐opioid receptors at the DMV inhibits Sst‐GABA DMV neurons.

Sst‐GABA DMV neurons may serve as integrative targets for modulating vagal output activity to the stomach.

We have previously shown that local GABA signalling in the brainstem is an important determinant of vagally‐mediated gastric activity. However, the neural identity of this GABA source is currently unknown. To determine this, we focused on the somatostatin positive GABA (Sst‐GABA) interneuron in the dorsal motor nucleus of the vagus (DMV), a nucleus that is intimately involved in regulating gastric activity. Also of particular interest was the effect of melanocortin and μ‐opioid agonists on neural activity of Sst‐GABA DMV neurons because their in vivo administration in the DMV mimics GABA blockade in the nucleus. Experiments were conducted in brain slice preparation of transgenic adult Sst‐IRES‐Cre mice expressing tdTomato fluorescence, channelrhodopsin‐2, archaerhodopsin or GCaMP3. Electrophysiological recordings were obtained from Sst‐GABA DMV neurons or DiI labelled gastric‐antrum projecting DMV neurons. Our results show that optogenetic stimulation of Sst‐GABA neurons results in a robust inhibition of action potentials of labelled premotor DMV neurons to the gastric‐antrum through an increase in inhibitory post‐synaptic currents. The activity of the Sst‐GABA neurons in the DMV is inhibited by both melanocortin and μ‐opioid agonists. These agonists counteract the pronounced inhibitory effect of Sst‐GABA neurons on vagal pre‐motor neurons in the DMV that control gastric motility. These observations demonstrate that Sst‐GABA neurons in the brainstem are crucial for regulating the activity of gastric output neurons in the DMV. Additionally, they suggest that these neurons serve as targets for converging CNS signals to regulate parasympathetic gastric function.
Proposal Design Procedure and Preliminary Simulation of Turbo Expander for Small Size (2–10 kW) Organic Rankine Cycle (ORC)
Authors: Capata Roberto , Hernandez Gustavo
Published: March 2016

Currently, one of the leading technologies for the “energy recovery” adopting a Rankine cycle (ORC) with organic fluids. ORC system operates like a conventional Rankine cycle, but instead of steam/water, uses an organic fluid. This change allows to convert low temperature heat and generate, where required, electricity. A large amount of studies were carried out to identify the most suitable fluids, system parameters and the various configurations. In reality, most ORC systems are designed and manufactured for recovery of thermal energy from various sources but at “large power rating” (exhaust gas turbines, internal combustion engines, geothermal sources, large melting furnaces, biomass, solar, etc.) from where it is possible to produce electric energy (30kW ÷ 300kW), but for the application of this system for small nominal power, as well as the exhaust gases of internal combustion engines (car sedan or town, ships, etc.) or smaller heat exchangers, there are very few applications. The aim of this work is to design a turbo-expander that meets system requirements: low pressure, small size, low mass flow rates.

The Expander must be adaptable to a small ORC system utilizing gas of a diesel engine or small gas turbine to produce 2–10 kW of electricity. The temperature and pressure of the exhaust gases, in this case study (400–600° C and at a pressure of 2 bar), imposes a limit on the use of an organic fluid and on the net power that can be produced. In addition to water, organic fluids such as CO2, R134a and R245fa have been considered. Once the fluid has been chosen operating, the turbine characteristics (dimensions, temperature, input and output pressure ratio, etc.) have been calculated and an attempt to find the “nearly-optimal” has been carried out. The detailed design of radial Expander is presented and discussed. An initial thermo-mechanical performance study is carried out to verify structural tension and possible displacement. Next step of the research here proposed will be the CFD simulation to improve or modify the chosen blade profile.
Reduction Techniques Methods for Simplifying Complex Kinetic Systems: A General Review
Authors: Nicolas Ghassan , Khanshan Fariba Seiyedzadeh , Metghalchi Hameed , West Richard H.
Published: March 2016

The development of kinetic models to describe the time evolution of chemically reacting systems is a fundamental objective of chemical kinetics. Ideally, the most accurate approach to this problem is to include all possible species and reactions of any importance to predict, within the specified uncertainty, a wide variety of experimental data. The complexity of these detailed models grows with an increase in the number of fuel components. When the detailed kinetic model is to be coupled to transport equations, the computational tasks often become formidable due to the intrinsic presence of a wide range of time and length scales, which result in the well-known stiffness problem. Such difficulties have motivated the development of numerous model order reduction techniques during the past three decades. In this paper, the most used reduction techniques for detailed kinetic models are presented and the advantages and disadvantages of each are explained.
Exergy Analysis and Optimization of a Building Air Conditioning System in Tropical Climate
Authors: Salazar Ricardo , Sciubba Enrico , Toro Claudia
Published: March 2016

The space conditioning sector is one of the highest exergy consumers and least efficient from the point of view of primary-to-end-use matching. Exergy analysis can be considered as a reliable tool for analyzing and optimizing energy consumption related to building conditioning systems.

The present study presents a comparative exergy analysis of the air conditioning system of the TOTAL S.A. offices located in Caracas, Venezuela to finally achieve a reduction of the global electric energy use of the considered building. Starting from the provided thermal cooling load, different possible cooling chains (primary-to-final energy conversion chain) are considered in order to locate the thermodynamically more efficient one from an exergetic point of view. The internal air handler unit, which provides for the cooled and dehumidified air to the building, is fed by the energy obtained from different possible converters of renewable energy primary sources. Specifically, solar and hybrid photovoltaic-thermal (PV/T) panels coupled with an absorption refrigeration machine and with an ejector refrigeration cycle are analyzed.

The study that has been carried on leads to identify the most convenient matching between final use and primary sources allowing to substantially reduce the global non-renewable energy consumption of the considered building.
Optimization of Smart Grid Solar Energy Application
Authors: Bello Olumide , Onyebueke Landon
Published: March 2016

This paper presents an approach to modeling of renewable energy integration into Smart Grid for Electric Vehicle charging applications.

Integration of renewable energy sources to smart grid is not only the key to smart Electric Vehicle charging but also the most efficient way to manage the distributed energy resources. It enables the ability to control, ease the peak load impacts, and protect distribution network components from being overloaded by Electric Vehicles. Thus, the electricity generation and consumption is managed in more cost effective way.

The developed model is a grid connected solar-assisted Electric Vehicle charging station, with battery bank. It generates electricity using solar photovoltaic (PV) arrays to augment the electricity used to charge the electric vehicles. The battery bank stores electricity from the grid and discharges the stored energy during periods of peak charging demand.

Optimization of the model was done by developing a program written in Visual Basic 2012. The computational results show the economic advantages of this model as well as the anticipated benefits of the smart grid for reduced peak loads, and increased efficiency.
Representing the Water-Energy Nexus With Decision Matrices
Authors: Weimann Jacob , Schmidt Matthew , Bergles Arthur , Compere Marc
Published: March 2016

The global water nexus is still in the formative stages as a area of study. The needs are mostly clear: people need adequate water for drinking, for growing food, for cooling steam-based power plants, and for sustaining the natural habitats that keep the carbon and hydrologic cycles functioning properly. What has emerged is a growing awareness of how finite the earth’s water resources are and how this creates a complex set of interconnected challenges in both developed and developing nations. What has also emerged are predictions with increasing urgency for water and energy crises in the next 20–50 years, especially if these concerns are left unaddressed.

The Water-Nexus is not new, but its emerging importance now is driven primarily by population growth, climate change, and our growing awareness of societal impact on ecosystems. Providing energy for buildings, homes, and transportation is an increasingly difficult task for the growing population and aging infrastructure. Most individual issues within the Water-Energy Nexus are fairly well known with quantifiable water impacts. What is lacking is a clear representation of the Nexus relationships that show how changes in one sector impact another. What is needed is a compact way to represent the interrelationships that provide both insight and perspective on how much influence one proposed change has compared to another. Such an understanding should surface the most strategic, viable methods for simultaneously meeting water and energy needs while being a good steward of finances and natural resources.

We propose the use of decision matrices from engineering design to represent the interconnected relationships that form the Water-Energy Nexus. The customers in this case are water-centric stakeholders such as government and corporate decision makers, educators, and water-oriented development agencies. Both quantitative and qualitative research methods are used to integrate the nexus topics into the decision matrix. Both positive and negative correlations in water impacts are indicated with their relative level of influence. Common units are used when possible to quantify water consumption or savings.

Decision matrices are presented for transportation fuels and utility power generation. The transportation fuels matrix includes evaluation criteria for water impact, sustainability, convenience, emissions, public opinion, and geographic considerations. The utility power decision matrix has similar evaluation criteria except capacity factor is considered instead of convenience. These criteria are intended to aid policy makers in strategically navigating the legislative and policy generation process to emphasize or reduce emphasis on different fuel types. Recommendations are provided for strategic, viable methods to mitigate future effects of the Water-Energy crisis.
Conversion of Glucose Into 5-Hydroxymethylfurfural in DMSO as Single Organic Solvent
Authors: Elmously Mohamed A. , Emara Ahmed , S. M. Abu-Elyazeed Osayed
Published: March 2016

Nowadays, 5-Hydroxymethylfurfural (HMF) is considered an important compound due to its economic importance, and due to the energy and waste crisis. It could provide a biofuel and alternatives of petrochemicals for various industrial applications. In the present work, 5-HMF was successfully produced with high yield by the dehydration of glucose in DMSO as organic solvent. DMSO was approved that it is highly selectivity of HMF (5-Hydroxymethylfurfural), and reducing the side reactions compared to water/DMSO as solvent. And the 5-HMF formation reaction was found to be faster in DMSO system than in water/DMSO. The influence of temperature and reaction time on the selectivity of DMSO was investigated over small range, to clarify the relation between temperature and time.
A Mathematical Model for Li-Air Battery Considering Volume Change Phenomena
Authors: Yoo Kisoo , Dutta Prashanta , Banerjee Soumik
Published: March 2016

Li-air battery has the potential to be the next generation energy storage device because of its much higher energy density and power density. However, the development of Li-air battery has been hindered by a number of technical challenges such as passivation of cathode, change in effective reaction area, volume change during charge and discharge, etc. In a lithium-air cell, the volume change can take place due to Li metal oxidation in anode during charge as well as due to the solubility of reaction product (lithium peroxide) in the electrolyte at cathode. In this study, a mathematical model is developed to study the performance of lithium-air batteries considering the significant volume changes at the anode and cathode sides using moving boundary technique. A numerical method was introduced to solve moving boundary problem using finite volume method. Using this model, the electric performance of lithium-air battery is obtained for various load conditions. Numerical results indicate that cell voltage drops faster with increase in load which is consistent with experimental observations. Also, the volume changes significantly affect the electric performance of lithium-air cell.
Combining Diesel Generators With Ultracapacitors to Enhance Stability and Reliability
Authors: Averbukh M. , Kuperman A. , Geula G. , Gadelovitch S. , Yuhimenko V.
Published: March 2016

Diesel generator based auxiliary power units (DG-APU) are widely used in different civil and military applications. Fuel economy and service life are probably the most important issues concerning their operation. Controlling engine throttle position in accordance with the load power allows regulating fuel supply to the engine to optimize fuel consumption. Despite the advantage of the method, control stability is sacrificed in case of light load operation as follows. When the DG-APU is running with a light load, engine throttle position should be nearly closed in order to minimize fuel consumption. If a load step is applied in such situation, engine velocity may drop sharply until complete stop because of insufficient control system bandwidth. This is why velocity and throttle position of a DG-APU should not be decreased below some level even if load power is low to maintain reliability at the expense of increased specific fuel consumption. Moreover, for small diesel-generators the throttle position is usually fixed. Thereby, relatively wide range load power variations (typical for many of diesel-generator applications) cause excessive fuel consumption.

The situation may be sufficiently improved by connecting ultracapacitors (UC) on the DG-APU output terminals, introducing additional inertia allowing smoothing engine velocity decrease during a sudden load increase thus providing more time to the control system to regulate throttle position. As a result, DG-APU would be operated much more efficiently at light loads without sacrificing stability. Moreover, the UC may be used at as starter motor power source, removing starting stress from electrochemical batteries. Present work investigates the improvements in UC-supported DG-APU fuel efficiency and stability compared to conventional technical solutions. The research is based on mathematical modeling of the entire system, verified by experiments. The results support the presented ideas and quantitatively demonstrate the improved fuel economy and reliability of small DG-APUs.
Ammonia Gasoline-Ethanol/Methanol Tertiary Fuel Blends as an Alternate Automotive Fuel
Authors: Haputhanthri Shehan Omantha , Maxwell Timothy Taylor , Fleming John , Austin Chad
Published: March 2016

Ammonia and hydrocarbon fuel blends, similar to ethanol and gasoline fuel blends can be used to commercialize ammonia as an alternative fuel. Feasibility of developing ammonia gasoline liquid fuel blends and the use of ethanol and methanol as emulsifiers to enhance the solubility of ammonia in gasoline were studied using thermostated vapor liquid equilibrium (VLE) high pressure cells, in this research. Solubility test results prove that emulsifier free pure gasoline is capable of dissolving 23 g/l of ammonia on mass basis (4.5% of ammonia on volume basis) at 345 kPa pressure and 286.65 K temperature in liquid phase. Solubility level is increased with the use of ethanol and methanol. Gasoline with 10% ethanol can retain 31.7 g/l (5.7% on volume basis) of ammonia in the liquid phase at the same pressure and temperature. Methanol has better emulsifying capabilities. Solubility level of gasoline with 30% methanol is 189.5 g/l (30.0% on volume basis). This paper presents solubility and dynamometer test results of five fuel blends E/M0, E10, M10, M20 and M30. Better performances are observed when the ammonia rich fuels are benchmarked against baseline fuel especially at higher engine speeds.
Biomass Gasification in a Pilot-Scale Gasifier
Authors: Shi Yunye , Sharma Tejasvi , Zang Guiyan , Ratner Albert
Published: March 2016

A study of the gasification of corn kernels has been performed on an experimental, pilot-scale (50–100 lbs/hour) gasification unit. Analysis was made on the performance of the gasifier in terms of producer gas generation and composition, char production and process mass balance. In these experiments corn kernels was used so that the shapes and sized of the materials did not influence the results. Experiments were conducted with varying temperature of fuel bed. For each experimental condition, the permanent gas composition was measured continuously by gas chromatography (GC). Tar was collected according to CEN Standard. Bio-char were weighted for mass balance. The results from the study indicate that there were differences between various operational parameters in terms of producer gas concentration and char percentage.
Thermal Transpiration Based Propulsion
Authors: Falkenstein-Smith Ryan , Zeng Pingying , Culp Tyler , Ahn Jeongmin
Published: March 2016

Thermal transpiration based propulsion is studied. Thermal transpiration describes flowing of the gas through a narrow channel with an imposed temperature gradient. As gas flows from the cold to hot side in the chamber, a pressure gradient is created across the channel induced by the temperature gradient. Between the two sides of the chamber an aerogel substance, which functions as an excellent insulator, is used as a thermal transpiration membrane and allows gas diffuse to the hot chamber. The induced pressure gradient is the driving factor in the propulsion of air, or any gas, into the chamber and through the porous membrane. The use of a porous substance such as aerogel as the transpiration membrane and a pressure gradient served as the two requirements in order to successfully achieve thermal transpiration. The gas diffusion through the aerogel transpiration membrane indicates that the average pore size of the aerogel must be comparable with the free path of the molecules. This concept can be taken further if the outlet chamber served as a combustion reactor. The flowing gas is motivated by the heat produced from the combustion process. Along with the exceptionally low thermal conductivity of the aerogel, the gas flow permits the propulsion device to be self-sustaining. The implications of providing a self-sustaining heat source signify that no external electrical heating is required. The effectiveness of this device can be measured as a function of the porous size of the membrane and the temperature difference applied to the system and pressure gradient created.
Dynamic Response of a Solid Oxide Fuel Cell Stack to Changes in a University Building’s Load
Authors: Whiston Michael M. , Collinge William O. , Bilec Melissa M. , Schaefer Laura A.
Published: March 2016

The load-following performance of a solid oxide fuel cell (SOFC) stack is investigated for meeting the power demand of a university building. A numerical model is developed based on charge, species mass, energy, and momentum balances, and an equivalent circuit is used to combine the fuel cell’s irreversibilities. The fuel cell stack is sized to meet the peak electric load of a building located on the University of Pittsburgh’s campus. The SOFC model is verified on electrochemical, mass, and thermal timescales. Results indicate that higher inlet gas pressures improve load-following by generating power closer to demand after settling has occurred, but higher pressures do not guarantee a desired power level. It is also found that lower fuel utilizations correspond to faster settling times on the mass flow timescale but with the disadvantage of lower efficiency. Lastly, it is shown that the thermal settling time decreases as the excess air ratio increases, with a slight increase in the air’s exhaust temperature.
Evaluation of Synthetic Natural Gas Production From Renewably Generated Hydrogen and Carbon Dioxide
Authors: Becker W. L. , Braun R. J. , Penev M.
Published: March 2016

The natural gas distribution infrastructure is well developed in many countries, enabling the fuel to be transported long distances via pipelines and easily delivered throughout cities. Using the existing pipeline to transport renewably generated synthetic natural gas (SNG) can leverage the value of the product. While the price of natural gas is near record lows in the United States, many other countries are working to develop SNG as an alternative fuel for transportation markets, especially in Europe and for island nations. This study presents an SNG plant design and evaluates its performance for producing SNG by reacting renewably generated hydrogen with carbon dioxide. The carbon dioxide feedstock is assumed to be captured and scrubbed from an existing coal fired power plant at the city-gate, where the SNG plant is co-located. Historically, methanation has been a common practice for eliminating carbon monoxide and carbon dioxide in various chemical processes such as ammonia production and natural gas purification; for these processes, only small amounts (1–3% molar basis) of carbon oxides need to be converted to methane. A “bulk” methanation process is unique due to the high concentration of carbon oxides and hydrogen. In addition, the carbon dioxide is the only carbon source, and the reaction characteristics of carbon dioxide are much different than carbon monoxide. Thermodynamic and kinetic considerations of the methanation reaction are explored to model and simulate a system of reactors for the conversion of hydrogen and carbon dioxide to SNG. Multiple reactor stages are used to increase temperature control of the reactor and drain water to promote the forward direction of the methanation reaction. Heat recuperation and recovery using organic Rankine cycle units for electricity generation utilizes the heat produced from the methanation reaction. Bulk recycle is used to increase the overall reactant conversion while allowing a satisfactorily high methane content SNG product. A hydrogen membrane separates hydrogen for recycle to increase the Wobbe index of the product SNG by increasing the methane content to nearly 93% by volume. The product SNG has a Wobbe index of 47.5 MJ/m3 which is acceptable for natural gas pipeline transport and end-use appliances in the existing infrastructure. The overall plant efficiency is shown to be 78.1% HHV and 83.2% LHV. The 2nd Law efficiency for the SNG production plant is 84.1%.
Optimal Design of IC Engine Cooling Fins by Using Genetic Algorithm
Authors: Yan Terry , Yobby Jason , Vundavilli Ravindra
Published: March 2016

The analysis for optimal design of an air-cooled internal combustion engine cooling fin array by using genetic algorithms (GA) is presented in this study. Genetic Algorithms are robust, stochastic search techniques which are also used for optimizing highly complex problems. In this study, the fin array is of the traditional circular fin type, which is subject to ambient convective heat transfer. The parameters (degrees of freedom) selected for the analysis include the cylinder wall thickness-to-radius ratio, fin thickness, fin length, the number of fins, and the local heat transfer coefficient. By using a single objective GA procedure, the heat transfer through the fin arrays is set as the objective function to be optimized with each parameter varied within the physical ranges. Proper population size is selected and the mutations, cross-over and selection are conducted in the GA procedure to arrive at the optimal set of parameters after a certain number of generations. The GA proves to be an effective optimization method in the thermal system component designs when the number of independent variables is large.
Evaluation of a Novel Concept for LNG Regasification in an Industrial Complex
Authors: Morosuk T. , Tesch S. , Schult M. , Tsatsaronis G.
Published: March 2016

New technologies that lead to an increased efficiency and lower product cost in each step of the LNG chain are of particular interest to scientists and engineers. The studies and commercial applications of LNG regasification processes can be divided into three large groups: (a) direct and indirect heat transfer processes between LNG and other substances in the so-called “traditional systems”, (b) LNG-based electricity generation systems, and (c) LNG regasification within an industrial complex consisting of an LNG import terminal and at least one different refrigeration or cryogenic plant (process).

In this paper the regasification of LNG is accomplished within an air separation process, to improve the overall system efficiency. The paper discusses the simulation, and the energetic, exergetic, and economic analyses of this novel cryogenic-based concept, which is characterized by a lower specific power requirement and improved cost effectiveness.
Combustion Characteristics of Jojoba Methyl Ester as an Alternative Fuel for Gas Turbine
Authors: Attia Ali M. A. , El-Zoheiry Radwan M. , El-Batsh Hesham M. , Shehata Mohamed S.
Published: March 2016

The strengthened requirements of new emission norms and the limited fuel resources are the major challenges for researchers over the world. The use of biofuels produced from vegetable oil will be a promising solution. In this case, Jojoba oil comes from very surprising plant as its seed contains 40–60% of its weight as raw oil and grows in desert. The trans-esterification process is used to convert jojoba oil into a Jojoba Methyl Ester (JME). This study aims to characterize the flame of JME as an alternative fuel in the gas turbines. Using of the premixed flame resulted in higher combustion efficiency and low emissions. The premixed flames for liquid fuels can be realized via use of lean premixed pre-vaporized (LPP) combustion method. In this work the jet fuel and blends of jet-JME fuel (with JME volume faction of 10, and 20%) are burned with LPP technique keeping the same equivalence ratio as it is used for burning the base jet fuel to determine the possibility to use the fuel mixture without any modifications in a specific LPP combustor. The main results indicate that, as volume content of JME increase the NOx emissions decrease to be lower than 10 ppm in case of B20. Moreover, the CO emission in case of B20 is higher than that of the jet fuel but at the end of the test section it does not exceed 0.15 %. In the same way, B20 produces higher UHC emissions than the jet fuel; however, at the end of the test section it does not exceed 80 ppm. So it can be concluded that blended Jojoba biodiesel can be used as an alternative fuel for jet fuel.
Solubility of Oxygen in Lithium-Air Battery Electrolytes: A Molecular Dynamics Study
Authors: Deshpande Anirudh , Dutta Prashanta , Banerjee Soumik
Published: March 2016

Ionic liquids are widely considered as potential electrolytes for lithium batteries due to their tunable electrochemical properties and extremely low vapor pressure, which makes them highly non-inflammable. However, the solubility of oxygen in ionic liquid based electrolytes is an important parameter that determines the performance of batteries. In the present study, we have employed molecular dynamics simulations to calculate the Henry’s constant and corresponding solubility values of atmospheric oxygen in N-methyl-N-propyl pyrrolidinium bis(trifluoromethanesulfonyl) imide (mppy+TFSI−) ionic liquids. After qualitatively validating the results at 323 K, we calculated the solubility of oxygen in mppy+TFSI−, as the ratio of the partial pressure of oxygen gas in the atmosphere and the Henry’s constant, at a range of temperatures that occur in realistic battery electrolytes. The solubility of oxygen increases with increasing temperature. Comparison of these solubility values with those of commonly used organic electrolytes provides valuable information regarding the feasibility of using ionic liquid electrolytes in lithium-air batteries.
Ab Initio Modeling of the Electron Transfer Reaction Rate at the Electrode-Electrolyte Interface in Lithium-Air Batteries
Authors: Kazemiabnavi Saeed , Dutta Prashanta , Banerjee Soumik
Published: March 2016

Lithium-air batteries are very promising energy storage systems for meeting current demands in electric vehicles. However, the performance of these batteries is highly dependent on the electrochemical stability and physicochemical properties of the electrolyte such as ionic conductivity, vapor pressure, static and optical dielectric constant, and ability to dissolve oxygen and lithium peroxide. Room temperature ionic liquids, which have high electrical conductivity, wide electrochemical stability window and also low vapor pressure, are considered potential electrolytes for these batteries. Moreover, since the physicochemical and electrochemical properties of ionic liquids are dependent on the structure of their constitutive cations and anions, it is possible to tune these properties by choosing from various combinations of cations and anions. One of the important factors on the performance of lithium-air batteries is the local current density. The current density on each electrode can be obtained by calculating the rate constant of the electron transfer reactions at the surface of the electrode. In lithium-air batteries, the oxidation of pure lithium metal into lithium ions happens at the anode. In this study, Marcus theory formulation was used to calculate the rate constant of the electron transfer reaction in the anode side using the respective thermodynamics data. The Nelsen’s four-point method of separating oxidants and reductants was used to evaluate the inner-sphere reorganization energy. In addition, the Conductor-like Screening Model (COSMO) which is an approach to dielectric screening in solvents has been implemented to investigate the effect of solvent on these reaction rates. All calculations were done using Density Functional Theory (DFT) at B3LYP level of theory with a high level 6-311++G** basis set which is a Valence Triple Zeta basis set with polarization and diffuse on all atoms (VTZPD) that gives excellent reproducibility of energies. Using this methodology, the electron transfer rate constant for the oxidation of lithium in the anode side was calculated in an ionic liquids electrolyte. Our results present a novel approach for choosing the most appropriate electrolyte(s) that results in enhanced current densities in these batteries.
Salinity Gradient Power Experiment Using Reverse Electrodialysis
Authors: Amaral Sean , Franklin Neil , Jurkowski Michael , Zenouzi Mansour
Published: March 2016

A relatively new form of alternative energy known as reverse electrodialysis (RED) appears to be one of the promising energy sources of the future. This technology harvests the energy stored in the salinity gradient between two different liquids, and converts it directly into electric power. This power is generated by pumping water through an array of alternating pairs of cation and anion exchange membranes called cells.

An experimental system was designed and assembled with cells 61 cm × 16.5 cm. Along with having much larger dimensions than the prototype systems reported in the literature, the design has an adjustable number of cells in the stack, allowing users to obtain test results at a variety of settings. Comparing the output of systems with few cells to systems with a higher number of cells will help us to optimize the stack size in terms of hydrodynamic losses.

Tests results have shown a voltage output of 1.98V, 83% of the predicted output. The current and power produced by the system did not meet theoretical output levels, but our group believes a redesign of the electrode rinse system will bring these values up to expectations. Future works will benefit from the learning experience.
Control of edge bulge evolution during photoresist reflow and its application to diamond microlens fabrication
Authors: Liu Hangyu , Herrnsdorf Johannes , Gu Erdan , Dawson Martin D.
Published: March 2016

The authors present an empirical study of profile evolution of lithographically defined photoresist (PR) patterns during thermal reflow and apply the findings to diamond microlens fabrication. During PR reflow, a bulge forms at the edge of the PR pattern and propagates inwards as the temperature and PR thickness are increased. An empirical relationship for this propagation is derived. Furthermore, it was found that at a certain reflow temperature and a limited pattern size, there is a minimum initial thickness of the PR pattern for forming spherical lens profiles. Based on these findings, diamond microlenses with a diameter of 400 μm and a previously unachieved radius of curvature of over 13 mm were fabricated. This is underpinned by forming PR microlens patterns with a large radius of curvature and transferring the PR patterns through low-selectivity Ar/Cl2 inductively coupled plasma etching.
TarO-specific inhibitors of wall teichoic acid biosynthesis restore β-lactam efficacy against methicillin-resistant staphylococci
Authors: Lee Sang Ho , Wang Hao , Labroli Marc , Koseoglu Sandra , Zuck Paul , Mayhood Todd , Gill Charles , Mann Paul , Sher Xinwei , Ha Sookhee , Yang Shu-Wei , Mandal Mihir , Yang Christine , Liang Lianzhu , Tan Zheng , Tawa Paul , Hou Yan , Kuvelkar Reshma , DeVito Kristine , Wen Xiujuan , Xiao Jing , Batchlett Michelle , Balibar Carl J. , Liu Jenny , Xiao Jianying , Murgolo Nicholas , Garlisi Charles G. , Sheth Payal R. , Flattery Amy , Su Jing , Tan Christopher , Roemer Terry
Published: March 2016

New inhibitors of wall teichoic acid biosynthesis restore susceptibility of drug-resistant staphylococci to β-lactam antibiotics.
Two-mAb cocktail protects macaques against the Makona variant of Ebola virus
Authors: Qiu Xiangguo , Audet Jonathan , Lv Ming , He Shihua , Wong Gary , Wei Haiyan , Luo Longlong , Fernando Lisa , Kroeker Andrea , Bovendo Hugues Fausther , Bello Alexander , Li Feng , Ye Pei , Jacobs Michael , Ippolito Giuseppe , Saphire Erica Ollmann , Bi Shengli , Shen Beifen , Gao George F. , Zeitlin Larry , Feng Jiannan , Zhang Boyan , Kobinger Gary P.
Published: March 2016

A two–monoclonal antibody cocktail protects nonhuman primates against Ebola virus 3 days after lethal exposure.
Back to the future: Rethinking global control of tuberculosis
Authors: Bloom Barry R. , Atun Rifat
Published: March 2016

If the ultimate goal of controlling an infectious disease is to interrupt transmission, the current global TB strategy is not succeeding.
The case against Zika virus
Authors: Bouvier Nicole M.
Published: March 2016

What case reports tell us—and don’t tell us—about Zika virus and birth defects.
Roots and routes of resistance
Authors: Thomas Anish
Published: March 2016

Drug-resistant cancer cells can both preexist and evolve from drug-tolerant cells; the path to resistance impacts response to additional treatment.