bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrogen and Compounds With Biological Activity From Microalgae
Authors: Rosa Marcos P. , Vargas Jose V. C. , Kava Vanessa M. , Dias Fernando G. , Savi Daiani , Santos Beatriz , Balmant Wellington , Mariano Andre B. , Servienski Andre , Ordóñez Juan C.
Published: December 2019

Microalgae have a high biotechnological potential as a source of biofuels (biodiesel, biohydrogen) and other high-added value products (e.g., pharmaceuticals, proteins, pigments). However, for microalgae cultivation to be economically competitive with other fuel sources, it is necessary to apply the concept of biorefinery. This seems to be the most ambitious strategy to achieve viability. Therefore, the objectives of this study were to isolate and identify the main microalgae line used to produce biofuels at Federal University of Parana, Brazil, using the rDNA sequence and micromorphological analysis, and to evaluate the potential of this lineage in the production of hydrogen and co-products with biological activity. For the purification of the lineage (LGMM0001), an aliquot was seeded into solid CHU culture medium and an isolated colony was selected. The genomic DNA was purified using a commercial kit (Macherey-Nagel, Düren, Germany) for molecular identification, the ITS region (ITS1, 5.8S and ITS2) (Internal Transcribed Spacer) was amplified and sequenced using primers LS266 and V9G. Morphological characterization was performed as described by Hemschemeier et al. [1]. Finally, for biological activity research, secondary metabolites were extracted by fractionation and evaluated against bacteria of clinical interest. Through microscopic analysis, general characteristics shared by the genus Tetradesmus were observed. The plasticity of the morphological characteristics of this genus reinforces the need for further studies to classify correctly the species in this group, using DNA sequencing. ITS sequence analysis of LGMM0001 showed 100% homology with sequences from the Tetradesmus obliquus species, so, the lineage was classified as belonging to this species. The evaluated microalgae strain was able to produce hydrogen, showing positive results for gas formation. Biological activity was observed with the extract obtained from the residual culture carried out with alternative medium used in the photobioreactors (PBR), against the Staphylococcus aureus pathogenic lineage. In conclusion, the microalgae strain used in this work was identified as Tetradesmus obliquus (= Acutodesmus obliquus), and was able to produce a compound with economic potential in association with the existing biofuel production process.
Dynamic Impedance Monitoring of Large Diameter-Vessel Sealing in Bipolar Electrosurgeries
Authors: Li Xiaoran , Yang Che-Hao , Chen Roland K. , Li Wei
Published: December 2019

Vessel sealing with a bipolar electrosurgical device has become a common practice in modern operation rooms. Despite all the advantages, such as easier operation, less bleeding, and shorter post-surgery recovery time, side effects including sticking, charring, and rebleeding, often occur, leading to increased operation time and sometimes complications that are potentially fatal. Tissue impedance during the electrosurgical procedure has been used to improve the surgical outcome However, this method has only been effective for small-diameter vessels of 3–5 mm. Overall, little is found in literature on dynamic impedance monitoring of blood vessel sealing using bipolar electrosurgical devices. In this study, an experimental setup was designed and built to perform vessel sealing tests on large-diameter blood vessels with mimicking blood flow. Ex vivo porcine carotid artery samples with a diameter about 7 mm were used. Burst pressures after sealing were measured. It was found that the tissue impedance started with an initial decrease, followed by a rapid increase, and ended with a plateau that was orders of magnitude higher than the initial impedance. The rapid increase of impedance provides indication of protein denaturing, thus the seal completion. This feature was used to monitor the electrosurgical vessel sealing process. It is shown that a burst pressure at least twice the normal human systolic blood pressure can be achieved with heating until the maximum tissue impedance is reached. A FEA model was developed in COMSOL to understand the dynamic impedance behavior in the vessel sealing process.
The Oriented Spray Cooling System for Heat Rejection and Evaporation
Authors: Bowman Charles F. , Taylor Robert E. , Hubble Jerry D.
Published: December 2019

Spray ponds offer significant advantages over mechanical draft cooling towers (MDCT) including superior simplicity and operability, lower preferred power requirements, and lower capital and maintenance costs. Unlike a conventional spray pond in which spray nozzles are arranged in a flat bed and water is sprayed upward, the Oriented Spray Cooling System (OSCS) is an evolutionary spray pond design in which nozzles are mounted on spray trees arranged in a circle and are tilted at an angle oriented towards the center of the circle. As a result, each nozzle is exposed to essentially ambient air as water droplets drag air into the spray region while the warm air concentrated in the center of the circle rises. Both of these effects work together to increase air flow through the spray region. Increased air flow reduces the local wet-bulb temperature (LWBT) of the air in the spray pattern, promoting heat transfer and more efficient cooling. The authors have developed analytical models to predict the thermal performance of the OSCS that are based on classical heat and mass transfer and kinetic vector relationships for spherical water droplets that rely only on generic experimental thermal performance data. Therefore, the model is not limited in application with regard to spray pressure or nozzle spacing or orientation and is not limited by droplet size considerations. This paper describes specific details such as nozzle type, orientation, and drop spectrum and details on the analytical model never before published that are used to predict the OSCS performance. The paper compares the predicted performance of the OSCS with the rigorous full-scale field test results that were measured in compliance with Nuclear Regulatory Commission requirements at the Columbia Generating Station (CGS) where the ultimate heat sink (UHS) is two OSCS.
Study on a New Solar Thermal Energy Complementary Power Generation System Based on Gas-Steam Combined Cycle
Authors: Liqiang Duan , Zhipeng Lv , Zhen Wang
Published: December 2019

The integrated solar energy-driven chiller combined cycle system (SCCC) has a problem of low annual solar energy utilization. The solar thermal efficiency and power output of the traditional integrated solar combined cycle system (ISCC) are limited by the integrated solar mirror field area and Rankine cycle efficiency. This paper presents a new system, on the basis of the combined cycle system with the three pressure HRSG with reheat, the solar energy is integrated into the chiller for cooling the compressor inlet air of gas turbine and the heat recovery steam generator (HRSG) for increasing the power output simultaneously. The Aspen Plus, TRNSYS and EBSILON softwares are applied in this paper to build the models of the overall system. The solar thermal efficiency, annual solar power generation and annual solar thermal efficiency are used to evaluate the performances of the new system, the traditional ISCC system and SCCC system. During the summer solstice, the proportions of solar energy used in cooling and heating are set as 40% and 60% in new system, respectively. The research results show that the new system has a higher power output (406.37MW), thermal cycle efficiency (53.61%) and solar thermal efficiency (48.85%) compared with the traditional ISCC system (385.63MW, 51.67%, and 24.43%, respectively) at the design point. The new system can regulates the proportions of solar energy used in the chiller and HRSG based on the monthly meteorological data, in order to maximize the annual solar energy utilization and annual solar power generation. The new system’s annual solar energy utilization hours (2071h) and solar power generation (25.863GW·h) are far greater than those of SCCC system (1498h, 18.185GW·h, respectively). Therefore, the proposed new system with the simultaneous integrations of solar energy with both the chiller and HRSG not only greatly increases the utilization rate of solar energy, but also has the significant thermodynamic advantages.
Time-of-Use Pricing in the Electricity Market: An Application of Stackelberg Game
Authors: Ketkar Atharva , Koonamparampath Joselyn , Sawant Mayur
Published: December 2019

Electrical power, generated and consumed, is perhaps, one of today’s most important construct in determining the progress of a people. The power mismatch between the generated and consumed power is one of the major issues faced in the electricity industry. This can be addressed by analysing user behaviour and manipulating it. This paper attempts to put forth a demand response (DR) technique using the concept of Time-of-Use (ToU) electricity pricing. The utilities have an upper hand of quoting the electricity price whereas the users must follow this price and give their best response of power consumption. This process is similar to a leader-follower setting as in a Stackelberg game where the follower acts according to the leader’s strategy and gives its best response in every situation. This paper proposes a pricing technique where the users are charged according to the amount of power consumed in the specific period of time.
Energy Consumption Difference Analysis of Key Parameters Variations of 1000MW Ultra-Supercritical Double Reheat Coal-Fired Power Generation System
Authors: Liqiang Duan , Jing Sun
Published: December 2019

This paper makes the energy consumption difference analysis of the key parameters variations of a 1000MW Ultra-Supercritical Double Reheat coal-fired power generation system. By applying the constant power variable condition calculation method for the steam turbine thermal system, the energy consumption difference analysis mode is established. The energy consumption difference of the key parameters variations (such as the main steam pressure, the main steam temperature and the exhaust steam pressure) of a 1000MW ultra-supercritical double reheat coal-fired power generation system at THA load, 75%THA load, 50%THA load and 40%THA load are investigated. The effects of the key parameter changes on the gross turbine heat rate and coal consumption rate at different working conditions are analyzed, as well as the corresponding energy consumption variation characteristic curves, and the variation rules of power generation efficiency are explored. In addition, the energy consumption difference variation rules of system at different working conditions are studied when any two key parameters such as the main steam temperature, main steam pressure, and the exhaust pressure change simultaneously. The research results show that within a certain range of variation, when the main steam temperature or the main steam pressure increase, or the exhaust gas pressure decreases, the energy consumption of the overall system drops. And with the reduction of load, the main steam temperature has the greatest influence on the coal consumption. By studying the effects of the simultaneous change of two key parameters on the energy consumption of the overall system, it is found that under the same load, the change of the exhaust gas pressure has the greatest influence on the system energy consumption. This paper will provide the theoretical guidance for the energy-saving diagnosis and operation optimization of ultra-supercritical double reheat coal-fired power generation system.
Processing of Agricultural Biomass for Producing Reinforced Polymer Composites
Authors: Dikici Birce , Motagi Samarth , Kantamani Prahruth , Ayyagari Suma , Villarroel Gustavo , Al-Haik Marwan
Published: December 2019

Fast growing plants or biomass wastes can be used as affordable and environmentally sustainable alternatives to synthetic insulation materials. The aim of this study was to investigate the mechanical properties (tensile strength and Young’s modulus) of natural fiber reinforced polymer composites as potential building materials. As a natural fiber, Bermuda grass seeds, conifer cones and pinecones are selected. The fundamental processes to develop nanofiber reinforced resin by processing agricultural waste fibers into nanocellulose is also investigated. Tensile tests are conducted to define stress/strain relationship. SEM tests are conducted to evaluate the surface topologies after fracture. The tensile fracture surfaces of composites were investigated. With the addition of Bermuda fibers, the stiffness of the vinyl ester sample was observed to increase by 624.2% compared to neat vinyl ester sample. With the addition of nanocellulose fibers, the stiffness of the composite was observed to increase by 53.3% compared to neat vinyl ester sample.
Underground CSP Thermal Energy Storage
Authors: Mahmud Roohany , Erguvan Mustafa , MacPhee David W.
Published: December 2019

Concentrated Solar Power (CSP) is one of the most promising ways to generate electricity from solar thermal sources. In this situation, large tracking mirrors focus sunlight on a receiver and provide energy input to a heat engine. Inside the receiver the temperature can be well above 1000°C, and molten salts or oils are typically used as heat transfer fluid (HTF). However, since the sun does not shine at night, a remaining concern is how to store thermal energy to avoid the use of fossil fuels to provide baseline electricity demand, especially in the late evenings when electricity demand peaks. In this study, a new method will be investigated to store thermal energy underground using a borehole energy storage system. Numerical simulations are undertaken to assess the suitability and design constraints of such systems using both molten salt as HTF.
Pyrolysis and CO2 Gasification of Composite Polymer Absorbent Waste for Syngas Production
Authors: Burra K. G. , Singh P. , Déparrois N. , Gupta A. K.
Published: December 2019

Development of alternative carbonaceous sources for energy production is essential to alleviate the dependence on depleting fossil fuels which led to increasing atmospheric CO2 and thus global warming. While biomass utilization for energy and chemical production has been extensively studied in the literature, such studies on municipal solid wastes is difficult to interpret due to the heterogeneous nature of the waste. Understanding of the influence of individual components is necessary for comprehensive development of waste-to-energy pathway. One such waste that is complicated and has often been ignored in the literature is composite polymer absorbent material waste which can also be considered as a potential feedstock for thermochemical pathway of energy production. Composite polymer absorbent materials are ubiquitously used these days in the form of sanitary napkins, diapers, water blockers, fire blockers and surgical pads due to their high water-absorptive nature. Pyrolysis and CO2 gasification is ideal for such materials due to its versatile feedstock intake and uniform product output in the form of syngas with adjustable composition. CO2 gasification also provides the added benefit of CO2 utilization which provides carbon offset to this process. In the present study, a mixture of cellulose, absorbent material (sodium polyacrylate), polypropylene and polystyrene in a fixed proportion, to model approximate composition of a diaper, was examined for its pyrolysis and CO2 gasification capability for viable syngas production. The influence of individual components into the syngas yield from the composite waste gasification was also investigated. A fixed-bed, semi-batch reactor facility along with gas chromatography was employed to analyse the syngas yield and compositional evolution. Pyrolysis was done under nitrogen atmosphere and gasification was done under CO2 atmosphere. CO2 gasification provided net CO2 consumption which means a net reduction in carbon emissions per joule of energy produced. The sample was tested under four isothermal conditions of 973, 1073, and 1173 K to understand the impact of operational conditions on the syngas yield. Influence of individual component of the composite absorbent waste on the syngas yield and composition was also analyzed by comparing these syngas characteristics with that of the yield from gasification of its individual components separately at 1173 K. These investigations provided us with novel results on the behavior and capabilities of these composite polymer absorbent wastes and which opens up a new avenue towards efficient utilization of solid waste resources for sustainable energy production in the form of syngas which can also be used for various chemicals production such as methanol, gasoline and other petrochemical products.
Flame Imaging of Highly Turbulent Premixed Methane-Air Combustion Using Planar Laser Induced Fluorescence (PLIF) of CH (C-X)
Authors: Hossain Md. Amzad , Islam Md Nawshad Arslan , Choudhuri Ahsan
Published: December 2019

The article presents an investigation of CH (C-X) planar laser induced fluorescence imaging (PLIF) of highly turbulent methane-air flames inside a windowed combustor. Flame dynamics and flame growth and evolution of methane-air flames stabilized over a backward facing step at high Reynolds Number (Re) (Re = 15000 and Re = 30000) with an equivalence ratio of 0.7 are discussed. It was observed that the flame evolution was faster at Re = 30000 than that of Re = 15000. The rate of initiation or formation of wrinkles, detachment of the wrinkles and burnout of the burned gases from the flame core increased with the increase in Re. The qualitative flame imaging shows that the width of the flame profile increases as the flame progress towards downstream and the flame becomes thinner as the turbulence level increases. An experimental methodology was developed to optimize the system for excitation, detection of the CH C-X band and post-processing the PLIF images.
Smart Sensor Technologies for Performance Optimization of Power Generating Assets
Authors: Sunder Raj Komandur
Published: December 2019

Significant research is ongoing on several fronts in smart sensor technologies for optimizing the performance of power generating assets. The initiatives include:

1. Real-time models with advanced computational algorithms, embedded intelligence at sensor and component level for reducing operating costs, improving efficiencies, and lowering emissions.

2. Optical sapphire sensors for monitoring operation and performance of critical components in harsh environments, for improving accuracy of measurements in combustion monitoring, and lowering operating costs.

3. Wireless technologies using (a) microwave acoustic sensors for real-time monitoring of equipment in high temperature/pressure environments (b) integrated gas/temperature acoustic sensors for combustion monitoring in diverse harsh environment locations to improve combustion efficiency, reduce emissions, and lower maintenance costs (c) sensors for sensing temperature, strain and soot accumulation inside coal-fired boilers for detailed condition monitoring, better understanding of combustion and heat exchange processes, improved designs, more efficient operation.

4. Distributed optical fiber sensing system for real-time monitoring and optimization of high temperature profiles for improving efficiency and lowering emissions.

5. Smart parts with embedded sensors for in situ monitoring of multiple parameters in existing and new facilities.

6. Optimizing advanced 3D manufacturing processes for embedded sensors in components for harsh environments to reduce costs and improve efficiency of power generation facilities with carbon capture capabilities.

7. New energy-harvesting materials for powering wireless sensors in harsh environments, improving reliability of wireless sensors in demanding environments, and in-situ monitoring and performance of devices and systems.

8. Real-time, accurate and reliable monitoring of temperature at distributed locations of sensors in harsh environments for improving operations and reducing operating costs.

9. Algorithms and methodologies for designing control systems utilizing distributed intelligence for optimal control of power generation facilities.

10. Gas sensors for monitoring high temperatures in harsh environments for lowering operating costs and better control of operations.

11. Optimizing placement of smart sensors in networks for cognitive behavior and self-learning.

This paper provides an overview of the initiatives in smart sensor technologies and their applications in optimizing the performance of power generating facilities.
Dynamic Modeling and Simulation of Home Cooling System With Supercooling-Based Ice Energy Storage
Authors: Zhang Yili , Kissick Sean , Wang Hailei
Published: December 2019

City’s electricity power grid is under heavy load during on-peak hours throughout summer cooling season. As the result, many utility companies implemented the time-of-use rate of electricity leading to high electricity cost for customers with significant cooling needs. On the other hand, the need for electricity and/or cooling decreases greatly at night, creating excess electricity capacity for further utilization. An innovative ice energy storage system is being developed leveraging a unique supercooling-based ice production process. During off-peak hours the proposed system stores the low-cost electric energy in the form of ice; during on-peak hours the system releases the stored energy to meet extensive home cooling needs. Thus, it can not only reduce energy and cost of cooling, but also increase the penetration of renewable energies (especially wind energy). In this paper, the working principles of the system is presented along with the modeling details of the overall system and several key components. The Simulink model takes in hourly temperature and peak/off peak electricity cost data to dynamically simulate the amount of energy required and associated cost for cooling an average home. Both energy consumption and cost for homes using the cooling system with ice energy storage in two US cities have been compared with those using conventional HVAC cooling system. According to the model, huge reduction in energy cost (up to 3X) can be achieved over six months of cooling season in regions with high peak electricity rates. While only moderate reduction on energy consumption is predicted for the ice energy storage system, further energy reduction potentials have been identified for future study.
Fluid Structure Interaction Analyses of Wind Turbines: The North Carolina Jennette’s Pier Turbines Case Study
Authors: Goudarzi Navid , Mohafez Mir Hamed , Williams Wesley
Published: December 2019

Wind power is known as an abundant source of energy that can be a promising alternative to conventional energy resources. Obtaining a competitive cost of energy for wind power harnessing technologies requires accurate resource assessment and design analyses. A robust, yet cost-effective wind turbine structure design reduces the chance of system failure in extreme events; it also reduces the operation and maintenance cost. This work obtains the required inputs for conducting fluid structure interaction (FSI) analyses of 3D Bergey Excel 10kW wind turbine installed in Jennette’s Pier in North Carolina. Six years (2013–2018) wind data (magnitude and direction) at the Jennette’s Pier are used to obtain the site wind characteristics. Some worthwhile data such as prevailing wind direction and wind speed, average air temperature, pressure and density are determined through this study. The flow field around the turbine blades is simulated to obtain the pressure distribution and aerodynamic coefficients using computational fluid dynamics (CFD) software, ANSYS Workbench. The results will be beneficiary to the researchers and engineers in evaluating the turbine performance in sites with wind characteristics similar to Jennette’s Pier. Moreover, the outputs of the work can be used for designing enhanced drivetrain components.
Experimental Investigation on Flow Field Characteristics by Drag Reducing Agent Additives in Stirred Vessel
Authors: Qi Xueyu , Wu Ting , Chen Yiming , Yang Ke , Zhao Wei , Wang Wei , Gong Jing
Published: December 2019

In this paper, experimental investigation on two oil-soluble DRAs were carried out in stirred vessel by standard six-blade Rushton, based on the application of particle image velocimeter (PIV). Two DRAs (1# and 2#) with different concentration from 3 ppm to 50 ppm were added into diesel respectively, and speed of impeller speed was set 400 rpm. Flow field characteristics including turbulence intensity, turbulent kinetic energy, energy dissipation rate influenced by those additives in stirred vessel were study. It was found that inhibition effect of turbulence intensity of the two DRAs is not obvious with concentration below 10 ppm. However, when concentration is above 10 ppm, turbulence inhibition effect become more obvious. Under low concentration, 1# has better turbulence inhibition effect in area near impeller, while 2# has better turbulence inhibition effect under high concentration. When the two DRAs are under the same concentration of 50ppm, turbulent flow energy and energy dissipation rate are obviously reduced.
The effects of musicality and language background on cue integration in pitch perception
Authors: Cui Aletheia , Kuang Jianjing
Published: December 2019

Pitch perception involves the processing of multidimensional acoustic cues, and listeners can exhibit different cue integration strategies in interpreting pitch. This study aims to examine whether musicality and language experience have effects on listeners' pitch perception strategies. Both Mandarin and English listeners were recruited to participate in two experiments: (1) a pitch classification experiment that tested their relative reliance on f0 and spectral cues, and (2) the Montreal Battery of Evaluation of Musical Abilities that objectively quantified their musical aptitude as continuous musicality scores. Overall, the results show a strong musicality effect: Listeners with higher musicality scores relied more on f0 in pitch perception, while listeners with lower musicality scores were more likely to attend to spectral cues. However, there were no effects of language experience on musicality scores or cue integration strategies in pitch perception. These results suggest that less musical or even amusic subjects may not suffer impairment in linguistic pitch processing due to the multidimensional nature of pitch cues.
Kaposi’s Sarcoma-Associated Herpesvirus Viral Interleukin-6 Signaling Upregulates Integrin β3 Levels and Is Dependent on STAT3
Authors: Rivera-Soto Ricardo , Dissinger Nathan J. , Damania Blossom
Published: December 2019

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the etiological agent of three human malignancies: multicentric Castleman’s disease, primary effusion lymphoma, and Kaposi’s sarcoma. Kaposi’s sarcoma is a highly angiogenic tumor that arises from endothelial cells. It has been previously reported that KSHV infection of endothelial cells leads to an increase of integrin αVβ3, a molecule observed to be involved in the angiogenic process of several malignancies. Our data demonstrate that the KSHV protein viral interleukin-6 (vIL-6) can induce integrin β3 in an intracellular and paracrine manner. Furthermore, we showed that this induction is necessary for vIL-6-mediated cell adhesion and angiogenesis, suggesting a potential role of integrin β3 in KSHV pathogenesis and development of Kaposi’s sarcoma.
Mutations in the Neuraminidase-Like Protein of Bat Influenza H18N11 Virus Enhance Virus Replication in Mammalian Cells, Mice, and Ferrets
Authors: Zhong Gongxun , Fan Shufang , Hatta Masato , Nakatsu Sumiho , Walters Kevin B. , Lopes Tiago J. S. , Wang Jessica I-Hsuan , Ozawa Makoto , Karasin Alexander , Li Yan , Tong Suxiang , Donis Ruben O. , Neumann Gabriele , Kawaoka Yoshihiro
Published: December 2019

Bats are reservoirs for several severe zoonotic pathogens. The genomes of influenza A viruses of the H17N10 and H18N11 subtypes have been identified in bats, but no live virus has been isolated. The characterization of artificially generated bat influenza H18N11 virus in mammalian cell lines and animal models revealed that this virus can acquire mammal-adapting mutations that may increase its zoonotic potential; however, the wild-type and mutant viruses did not replicate to high titers in all infected animals.
Siz2 Prevents Ribosomal DNA Recombination by Modulating Levels of Tof2 in Saccharomyces cerevisiae
Authors: Abraham Neethu Maria , Ramalingam Kathirvel , Murthy Saketh , Mishra Krishnaveni
Published: December 2019

The genes that encode rRNA in
Saccharomyces cerevisiae
are organized as multiple repeats. The repetitive nature and heavy transcription of this region make it prone to DNA breaks. DNA breaks could lead to recombination, which could result in either loss or gain of repeats with detrimental consequences to the cell. Multiple mechanisms operate to maintain the stability of rDNA. Earlier studies reported that the absence of Ulp2, a deSUMOylase, resulted in declining levels of Tof2 and thereby disrupted rDNA silencing. In contrast, our findings suggest that accumulation of Tof2 can also result in increased rDNA recombination, through a mechanism that involves Fob1, an RFB-bound protein. While our study has examined only Tof2, rDNA recombination could be regulated by other proteins through a mechanism similar to this.
Streptococcus gordonii Type I Lipoteichoic Acid Contributes to Surface Protein Biogenesis
Authors: Lima Bruno P. , Kho Kelvin , Nairn Brittany L. , Davies Julia R. , Svensäter Gunnel , Chen Ruoqiong , Steffes Amanda , Vreeman Gerrit W. , Meredith Timothy C. , Herzberg Mark C.
Published: December 2019

Discovered over a half-century ago, lipoteichoic acid (LTA) is an abundant polymer found on the surface of Gram-positive bacteria. Although LTA is essential for the survival of many Gram-positive species, knowledge of how LTA contributes to bacterial physiology has remained elusive. Recently, LTA-deficient strains have been generated in some Gram-positive species, including the human oral commensal
Streptococcus gordonii
. The significance of our research is that we utilized an LTA-deficient strain of
S. gordonii
to address why LTA is physiologically important to Gram-positive bacteria. We demonstrate that in
S. gordonii
, LTA plays an important role in the presentation of many cell surface-associated proteins, contributing to cell envelope homeostasis, cell-to-cell interactions in biofilms, and adhesion to eukaryotic cells. These data may broadly reflect a physiological role of LTA in Gram-positive bacteria.
Encephalitis secondary to nitrous oxide and vitamin B12deficiency
Authors: Hughes Gareth , Moran Ed , Dedicoat Martin J
Published: December 2019

A 27-year-old woman presented with confusion, agitation and fever. Having initially been treated as an infective encephalitis case her initial and subsequent lumbar punctures revealed cerebrospinal fluid with a worsening pleocytosis and elevated protein. It was initially felt she had been suffering from tuberculous meningitis and started on treatment it later became apparent that she had a severe vitamin B12deficiency related to recreational nitrous oxide use. She also was noted to have a peripheral neuropathy. After replacing her vitamin B12and later stopping her tuberculous medication once cultures were negative her cognition and peripheral neuropathy continued to improve.
Effective coverage and budget implications of skill-mix change to improve neonatal nursing care: an explorative simulation study in Kenya
Authors: Tsiachristas Apostolos , Gathara David , Aluvaala Jalemba , Chege Timothy , Barasa Edwine , English Mike
Published: December 2019

Introduction

Neonatal mortality is an urgent policy priority to improve global population health and reduce health inequality. As health systems in Kenya and elsewhere seek to tackle increased neonatal mortality by improving the quality of care, one option is to train and employ neonatal healthcare assistants (NHCAs) to support professional nurses by taking up low-skill tasks.

Methods

Monte-Carlo simulation was performed to estimate the potential impact of introducing NHCAs in neonatal nursing care in four public hospitals in Nairobi on effectively treated newborns and staff costs over a period of 10 years. The simulation was informed by data from 3 workshops with >10 stakeholders each, hospital records and scientific literature. Two univariate sensitivity analyses were performed to further address uncertainty.

Results

Stakeholders perceived that 49% of a nurse full-time equivalent could be safely delegated to NHCAs in standard care, 31% in intermediate care and 20% in intensive care. A skill-mix with nurses and NHCAs would require ~2.6 billionKenyan Shillings (KES) (US$26 million) to provide quality care to 58% of all newborns in need (ie, current level of coverage in Nairobi) over a period of 10 years. This skill-mix configuration would require ~6 billion KES (US$61 million) to provide quality of care to almost all newborns in need over 10 years.

Conclusion

Changing skill-mix in hospital care by introducing NHCAs may be an affordable way to reduce neonatal mortality in low/middle-income countries. This option should be considered in ongoing policy discussions and supported by further evidence.
Comparative efficacy and safety of probiotics for the treatment of irritable bowel syndrome: a systematic review and network meta-analysis protocol
Authors: Yang Man , Yu Yuanyuan , Lei Ping-Guang , Yuan Jinqiu
Published: December 2019

Introduction

Irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disorder affecting approximately 10% to 25% of the adult population. A large number of clinical trials have been conducted to evaluate the efficacy of probiotics for IBS but the results were inconsistent. Previous meta-analyses have shown that probiotics are effective for IBS, but the comparative efficacy of individual species is unclear. In addition, evidence regarding the superiority of combination over single probiotic is still lacking. We, therefore, perform this study to evaluate the comparative efficacy and safety of various species of probiotics, and combination regimens for the treatment of IBS.

Methods and analysis

This study is a systematic review with network meta-analysis. We will search PubMed, Scopus, The Cochrane Central Register of Controlled Trials and CINAHL for randomised controlled trials comparing probiotics with placebo or comparing different probiotics for IBS, with no language restrictions. The primary outcomes will be treatment response and global IBS-symptom score. We will initially combine included studies with traditional pairwise meta-analysis and then with random-effects network meta-analysis. We will quantify the effect of potential effect modifiers by meta-regression if appropriate. We will check the consistency assumption by testing the absolute difference between direct and indirect estimates for comparisons in closed loops. The quality of evidence will be evaluated according to the GRADE framework.

Ethics and dissemination

Ethical approval is not required for literature-based studies. We will disseminate the findings through publications in peer-reviewed journals and relevant conferences.

PROSPERO registration number

CRD42018102101
Cutaneous manifestation of Mycobacterium avium complex infection in an Australian shepherd dog
Authors: Ramos Sara J , Woodward Michelle C , Wakamatsu Nobuko , Bolin Steven R , Friedman Martha Lane
Published: December 2019

A three‐year‐old male neutered Australian shepherd dog presented with a one‐week history of diffuse ulcerative cutaneous nodules. On physical examination the dog had generalised lymphadenomegaly with multiple well‐circumscribed subcutaneous to dermal nodules with central haemorrhagic ulceration affecting the face, dorsum, dorsal cervical area and abdomen. Histopathological findings revealed severe suppurative and pyogranulomatous dermatitis and panniculitis with acid‐fast pleomorphic bacterium present. Mycobacterial culture of tissue was negative. Repeated PCR assays on formalin‐fixed tissue followed by nucleic acid sequencing confirmed the presence of Mycobacterium avium complex. Treatment was initiated with clarithromycin (10.9 mg/kg orally every 12 hours) and rifampin (13.2 mg/kg orally every 24 hours) and resulted in clinical resolution of the lesions within two weeks. Treatment was continued for six months and then discontinued. Seventeen months following treatment discontinuation, the dog was clinically and systemically well with no relapse noted.
A model form for stem taper and volume estimates of Asian white birch (Betula platyphylla): a major commercial tree species of Northeast China
Authors: Shahzad Muhammad Khurram , Hussain Amna , Jiang Lichun
Published: December 2019

Stem taper functions are valuable tools for the study of stem profile and predict volume estimates. Such functions have long been analyzed for different birch species in the world. However, Asian white birch (Betula platyphylla Suk.) has not yet been investigated as an individual species in China or abroad. This study presents stem taper and volume equations for B. platyphylla in Northeast China. Eight commonly used taper functions were fit to the data of 615 destructively sampled trees from two regions of Northeast China. A second-order continuous autoregressive error structure was incorporated to address the autocorrelation in the data and to achieve the valid parameter estimation. The condition number was used to detect the multicollinearity in the models. The taper functions were compared in terms of overall evaluation statistics and by examining the box plots of diameter and volume residuals against relative heights and diameter classes. The equations of A. Kozak (2004, For. Chron. 80(4): 507–515; model 2), Z. Fang et al. (2000, For. Sci. 46(1): 1–12), and H. Bi (2000, For. Sci. 46(3): 397–409) were the leading models for diameter and volume estimates. Overall, the equation of Z. Fang et al. (2000, For. Sci. 46(1): 1–12) exhibited the best results for estimating diameter and total and merchantable volumes in terms of statistical performance and lower multicollinearity.
Scrutinization of 2D and mixed convection flow of generalized Newtonian fluid with nanoparticles and magnetic field
Authors: Sardar Humara , Ahmad Latif , Khan Masood
Published: December 2019

In this research paper we focus on presenting the local non-similar solutions for two-dimensional steady and mixed convective flow of electrically conducting Carreau nanofluid under the influence of Brownian motion and thermophoresis effects. This research paper also presents the new mass flux boundary condition of nanoparticles. The governing partial differential equations are converted into ordinary differential equations by using the local non-similar transformations called the Sparrow–Quack–Boerner local non-similar method. A numerical approach is used to investigate the local non-similar solutions of the entire problem. Outcomes for the skin friction and rate of heat and mass transfer have been obtained and discussed for parametric variations of the buoyancy parameter ξ, magnetic parameter M, Weissenberg number We, viscosity ratio parameter β*, Brownian motion parameter Nb, thermophoresis parameter Nt, Prandtl number Pr, and Schmidt number Sc. From the obtained results a considerable increase in the skin friction coefficient is observed with an increase in buoyancy parameter ξ. Also, ξ shows relative growth for the momentum and concentration profiles.
Validation of transfer map calculation for electrostatic deflectors in the code COSY INFINITY
Authors: Valetov Eremey , Berz Martin , Makino Kyoko
Published: December 2019

The code COSY INFINITY uses a beamline coordinate system with a Frenet–Serret frame relative to the reference particle, and calculates differential algebra-valued transfer maps by integrating the ODEs of motion in the respective vector space over a differential algebra (DA).

We described and performed computation of the DA transfer map of an electrostatic spherical deflector in a laboratory coordinate system using two conventional methods: (1) by integrating the ODEs of motion using a numerical integrator and (2) by computing analytically and in closed form the properties of the respective elliptical orbits from Kepler theory. We compared the resulting transfer maps with (3) the DA transfer map of COSY INFINITY’s built-in electrostatic spherical deflector element [Formula: see text] and (4) the transfer map of the electrostatic spherical deflector computed using the program GIOS, which uses analytic formulas from a paper1 by Hermann Wollnik regarding second-order aberrations.

In addition to the electrostatic spherical deflector, we studied an electrostatic cylindrical deflector, where the Kepler theory is not applicable. We computed the DA transfer map by the ODE integration method (1), and we compared it with the transfer maps by (3) COSY INFINITY’s built-in electrostatic cylindrical deflector element [Formula: see text] and (4) GIOS.

The transfer maps of electrostatic spherical and cylindrical deflectors obtained using the direct calculation methods (1) and (2) are in excellent agreement with those computed using (3) COSY INFINITY. On the other hand, we found a significant discrepancy with (4) the program GIOS.
Electrophysical properties of the (SnSe)1−x–(SmSe)x solid solutions at high and low temperature
Authors: Abdurahmanova V. A. , Abdullaev N. M. , Ismayilov Sh. S.
Published: December 2019

The temperature range of [Formula: see text] = 77–770 K in the system alloys: Holl coefficient [Formula: see text], thermo-emf [Formula: see text], electric conductivity [Formula: see text], measured [Formula: see text]-density of components and analyzed. It has been established that samarium additive atoms contain donor-type properties and the effectiveness increases with the temperature increase: up to 40% proportional to [Formula: see text] K in [Formula: see text]-type specimens, whereas in [Formula: see text]-type samples this increase is higher and covers the contents of pH varying from [Formula: see text] to [Formula: see text]. An electrical conductivity of compounds increased due to the carrier activation with further increase of temperature. The activation energy of carriers at low temperatures ([Formula: see text] K) is [Formula: see text] eV for [Formula: see text] mol.% and [Formula: see text] mol.% compounds at [Formula: see text] = 77–320 K and for [Formula: see text] mol.% and [Formula: see text] mol.% compounds are [Formula: see text] eV. [Formula: see text] const at [Formula: see text]–400 K for [Formula: see text] mol.% and [Formula: see text] mol.% compounds, and passing with minimum increases at [Formula: see text] = 400–500 K.
The analysis of high-capacity quantum secure direct communication using polarization and orbital angular momentum of photons
Authors: Li Lin-Yi , Wang Tie-Jun , Wang Chuan
Published: December 2019

Higher channel capacity and noise elimination are the key requirements for the implementation of long-distance quantum communication. As the additional degrees of freedom (DoF) of photons can be employed to achieve higher channel capacity and security beyond the polarizations DoF of photons, the photonic qubits are always employed as the flying qubits in quantum communication and quantum information processing. Here, exploiting the multiple DoFs of photons, we present an efficient quantum secure direct communication protocol based on the coding and manipulation of qubits on both the polarization and the orbital angular momentum of photons. Also, the numerical simulation is studied to further clarify the improvement of the channel capacity and the security. It is found that the channel capacity and the error rate (caused by eavesdropping) of the QSDC protocol which encoded on the polarization DoF and the OAM DoF is significantly higher than that of coding on only polarization DoF. We believe this work could provide more evidence for the applications of higher-dimensional qubits in quantum information science.
Influence of multi-sintering on the thermoelectric properties of Bi2Sr2Co2Oy ceramics
Authors: Zhang Y. , Fan M. M. , Ruan C. C. , Zhang Y. W. , Li X.-J. , Song H. Z.
Published: December 2019

[Formula: see text] ceramic samples have a structure similar to phonon glass electronic crystals, and their thermoelectric properties can be effectively adjusted through repeated grinding and sintering. The results show that multi-sintering can make their grain refined and increase their grain boundary, which will effectively increase density and phonon scattering. Finally, multi-sintering can reduce the resistivity and thermal conductivity, thus obviously improve thermoelectric figure of merit [Formula: see text] of [Formula: see text]. The optimum [Formula: see text] value of 0.26 is achieved at 923 K by the third sintered sample.
Stability of the composite wave for compressible Navier–Stokes/Allen–Cahn system
Authors: Luo Ting , Yin Haiyan , Zhu Changjiang
Published: December 2019

This paper is devoted to the study of the nonlinear stability of the composite wave consisting of two rarefaction waves and a viscous contact wave for the Cauchy problem to a one-dimensional compressible non-isentropic Navier–Stokes/Allen–Cahn system which is a combination of the classical Navier–Stokes system with an Allen–Cahn phase field description. We first construct the composite wave through Euler equations under the assumption of [Formula: see text] for the large time behavior, and then prove that the composite wave is time asymptotically stable under small perturbations for the corresponding Cauchy problem of the non-isentropic Navier–Stokes/Allen–Cahn system. The proof is mainly based on a basic energy method.
Ab Initio Study on the Lower Mantle Minerals
Authors: Tsuchiya Taku , Tsuchiya Jun , Dekura Haruhiko , Ritterbex Sebastian
Published: December 2019

Recent progress in theoretical mineral physics based on the ab initio quantum mechanical computation method has been dramatic in conjunction with the rapid advancement of computer technologies. It is now possible to predict stability, elasticity, and transport properties of complex minerals quantitatively with uncertainties that are comparable to or even smaller than those attached in experimental data. These calculations under in situ high-pressure ( P) and high-temperature conditions are of particular interest because they allow us to construct a priori mineralogical models of the deep Earth. In this article, we briefly review recent progress in studying high- P phase relations, elasticity, thermal conductivity, and rheological properties of lower mantle minerals including silicates, oxides, and some hydrous phases. Our analyses indicate that the pyrolitic composition can describe Earth's properties quite well in terms of density and P- and S-wave velocity. Computations also suggest some new hydrous compounds that could persist up to the deepest mantle and that the postperovskite phase boundary is the boundary of not only the mineralogy but also the thermal conductivity. ▪  The ab initio method is a strong tool to investigate physical properties of minerals under high pressure and high temperature. ▪  Calculated thermoelasticity indicates that the pyrolytic composition is representative to the chemistry of Earth's lower mantle. ▪  Simulations predict new dense hydrous phases stable in the whole lower mantle pressure and temperature condition. ▪  Calculated lattice thermal conductivity suggests a heat flow across the core mantle boundary no greater than 10 TW.