bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on power sharing strategy of hybrid energy storage system in photovoltaic power station based on multi‐objective optimisation
Authors: Jiang Wei , Zhang Lei , Zhao Hui , Huang Huichun , Hu Renjie
Published: February 2016

Battery/supercapacitor (SC) hybrid energy storage system (HESS) is an effective way to suppress the power fluctuation of photovoltaic (PV) power generation system during radiation change. This study focuses on the power sharing between different energy storage components with two optimisation objectives: energy loss and state of charge of SC. First, the topology of HESS and its connection with PV system are analysed. Second, the control targets of the HESS have been organised as optimisation objectives. A linear weighted summation algorithm based on variable weights is proposed to solve the multi‐objective optimisation problem to obtain current reference of SC and battery. Third, the energy management system of the HESS is designed based on proposed algorithms. Simulation and experiment results verified the proposed algorithms and control strategy.
Very long distance connection of gigawatt‐size offshore wind farms: extra high‐voltage AC versus high‐voltage DC cost comparison
Authors: Lauria Stefano , Schembari Maddalena , Palone Francesco , Maccioni Marco
Published: February 2016

This study presents a cost comparison between commercially available high‐voltage DC (HVDC) and extra high‐voltage AC shore connection (±320 kV voltage source converter and 420 kV–50 Hz single‐core and three‐core cables), for a 1 GW offshore wind farm cluster, considering transmission distances up to 400 km. The HVDC system is a point‐to‐point connection whereas multiple AC intermediate compensating stations are envisaged for AC when needed. Capital costs are evaluated from recently awarded contracts, operating costs include energy losses and missed revenues due to transmission system unavailability, both estimated using North Sea wind production curves. Optimal AC intermediate compensation, if any, and reactive profiles are also taken into account. Resultsshow that HVDC has lower transmission losses at distances in excess of 130 km; however, due to the combined effect of lower AC capital cost and unavailability, using three‐core aluminium cables can be more convenient up to 360 km distance.
Assessment of potential for photovoltaic roof installations by extraction of roof tilt from light detection and ranging data and aggregation to census geography
Authors: Palmer Diane , Cole Ian , Betts Thomas , Gottschalg Ralph
Published: February 2016

Large‐scale adoption of solar photovoltaics (PV) in the built environment requires automation of roof suitability surveying over large geographical areas. Furthermore, as local PV installation density increases, electricity network operators require clearer information on the overall impact the large number of different rooftop PV systems will have on the stability of the local network. Knowledge of roof features (tilt angle, azimuth angle and area) and localised in‐plane irradiance data is essential to meet both of these requirements. Such information is currently not available (except by individual roof surveying by PV consultants) and has to be generated. This study demonstrates the automated extraction of building roof plane characteristics from existing wide‐area, aircraft‐based light detection and ranging data. These characteristics are then aggregated statistically and scaled‐up to produce a UK‐wide map of average roof tilt variation. Validation of roof tilt with site measurements taken by four different methods demonstrates a mean absolute error of 3°. For major roof plane azimuth angles, banded into compass octants, accurate detection was achieved in 100% of cases, validated by inspection of aerial photography. This is sufficient for calculating in‐plane irradiance for a more detailed automated assessment.
Solar PV yield and electricity generation in the UK
Authors: Mason Nigel B.
Published: February 2016

The annual yield for solar photovoltaic (PV) electricity generation in the UK is calculated for the installed capacity at the end of 2014 and found to be close to 960 kWh/kWp. This value is derived by averaging expected PV yield in different regions of the UK, weighted according to the regionally installed generating capacity from UK government statistics and has an estimated uncertainty of ±5%. The mean generating yield can vary with time as newly deployed PV may change the regional distribution of installed power and the variation over the period 2010–2014 is charted. The installed generating capacity at September 2015 was 8.19 GWp and, based on the above yield, should generate around 7860 GWh of electricity in a typical year or 2.6% of UK consumption (2014). Based on current trends, Solar PV electricity should exceed 3% of UK consumption in 2016.
Reference Correlation of the Thermal Conductivity of Carbon Dioxide from the Triple Point to 1100 K and up to 200 MPa
Authors: Huber M. L. , Sykioti E. A. , Assael M. J. , Perkins R. A.
Published: February 2016

This paper contains new, representative reference equations for the thermal conductivity of carbon dioxide. The equations are based in part upon a body of experimental data that has been critically assessed for internal consistency and for agreement with theory whenever possible. In the case of the dilute-gas thermal conductivity, we incorporated recent theoretical calculations to extend the temperature range of the experimental data. Moreover, in the critical region, the experimentally observed enhancement of the thermal conductivity is well represented by theoretically based equations containing just one adjustable parameter. The correlation is applicable for the temperature range from the triple point to 1100 K and pressures up to 200 MPa. The overall uncertainty (at the 95% confidence level) of the proposed correlation varies depending on the state point from a low of 1% at very low pressures below 0.1 MPa between 300 and 700 K, to 5% at the higher pressures of the range of validity.
Electronic spectra of 2- and 3-tolunitrile in the gas phase. II. Geometry changes from Franck-Condon fits of fluorescence emission spectra
Authors: Gmerek Felix , Stuhlmann Benjamin , Álvarez-Valtierra Leonardo , Pratt David W. , Schmitt Michael
Published: February 2016

We determined the changes of the geometries of 2- and 3-tolunitrile upon excitation to the lowest excited singlet states from Franck-Condon fits of the vibronic intensities in several fluorescence emission spectra and of the rotational constant changes upon excitation. These structural changes can be connected to the altered electron distribution in the molecules and are compared to the results of ab initio calculations. We show how the torsional barriers of the methyl groups in both components are used as probe of the molecular changes upon electronic excitation.
Visualization and analysis of the Kohn-Sham kinetic energy density and its orbital-free description in molecules
Authors: Cancio Antonio C. , Stewart Dane , Kuna Aeryk
Published: February 2016

We visualize the Kohn-Sham kinetic energy density (KED) and the ingredients — the electron density, its gradient, and Laplacian — used to construct orbital-free models of it, for the AE6 test set of molecules. These are compared to related quantities used in metaGGA’s, to characterize two important limits — the gradient expansion and the localized-electron limit typified by the covalent bond. We find the second-order gradient expansion of the KED to be a surprisingly successful predictor of the exact KED, particularly at low densities where this approximation fails for exchange. This contradicts the conjointness conjecture that the optimal enhancement factors for orbital-free kinetic and exchange energy functionals are closely similar in form. In addition we find significant problems with a recent metaGGA-level orbital-free KED, especially for regions of strong electron localization. We define an orbital-free description of electron localization and a revised metaGGA that improves upon atomization energies significantly.
An investigation of one- versus two-dimensional semiclassical transition state theory for H atom abstraction and exchange reactions
Authors: Greene Samuel M. , Shan Xiao , Clary David C.
Published: February 2016

We investigate which terms in Reduced-Dimensionality Semiclassical Transition State Theory (RD SCTST) contribute most significantly in rate constant calculations of hydrogen extraction and exchange reactions of hydrocarbons. We also investigate the importance of deep tunneling corrections to the theory. In addition, we introduce a novel formulation of the theory in Jacobi coordinates. For the reactions of H atoms with methane, ethane, and cyclopropane, we find that a one-dimensional (1-D) version of the theory without deep tunneling corrections compares well with 2-D SCTST results and accurate quantum scattering results. For the “heavy-light-heavy” H atom exchange reaction between CH3 and CH4, deep tunneling corrections are needed to yield 1-D results that compare well with 2-D results. The finding that accurate rate constants can be obtained from derivatives of the potential along only one dimension further validates RD SCTST as a computationally efficient yet accurate rate constant theory.
Developments in stochastic coupled cluster theory: The initiator approximation and application to the uniform electron gas
Authors: Spencer James S. , Thom Alex J. W.
Published: February 2016

We describe further details of the stochastic coupled cluster method and a diagnostic of such calculations, the shoulder height, akin to the plateau found in full configuration interaction quantum Monte Carlo. We describe an initiator modification to stochastic coupled cluster theory and show that initiator calculations can at times be extrapolated to the unbiased limit. We apply this method to the 3D 14-electron uniform electron gas and present complete basis set limit values of the coupled cluster singles and doubles (CCSD) and previously unattainable coupled cluster singles and doubles with perturbative triples (CCSDT) correlation energies for up to rs = 2, showing a requirement to include triple excitations to accurately calculate energies at high densities.
Bias voltage dependence of two-step photocurrent in GaAs/AlGaAs quantum well solar cells
Authors: Noda T. , Elborg M. , Mano T. , Kawazu T. , Han L. , Sakaki H.
Published: February 2016

We investigated photoresponses of AlGaAs solar cells in which coupled GaAs quantum wells were embedded in the i-region of p-i-n diodes; we studied how the bias voltage Vb affects the normal photocurrent I generated by the visible light and a “two-step” photocurrent ΔI generated by the absorption of visible and infrared photons. We found that as Vb exceeds −0.2 V, ΔI rises and peaks at 0.6 V, while the normal photocurrent I falls to about half of its saturated level. These findings are discussed in terms of a rate equation model to show that ΔI is mainly determined by the balance of escape and recombination of photogenerated carriers.
Effect of Ni content on the morphological evolution of Ni-YSZ solid oxide fuel cell electrodes
Authors: Chen-Wiegart Yu-chen Karen , Kennouche David , Scott Cronin J. , Barnett Scott A. , Wang Jun
Published: February 2016

The coarsening of Ni in Ni–yttria-stabilized zirconia (YSZ) anodes is a potential cause of long term solid oxide fuel cells (SOFC) performance degradation. The specifics of the Ni-YSZ structure—including Ni/YSZ ratio, porosity, and particle size distributions—are normally selected to minimize anode polarization resistance, but they also impact long-term stability. A better understanding of how these factors influence long-term stability is important for designing more durable anodes. The effect of structural details, e.g., Ni-YSZ ratio, on Ni coarsening has not been quantified. Furthermore, prior measurements have been done by comparing evolved structures with control samples, such that sample-to-sample variations introduce errors. Here, we report a four dimensional (three spatial dimensions and time) study of Ni coarsening in Ni-YSZ anode functional layers with different Ni/YSZ ratios, using synchrotron x-ray nano-tomography. The continuous structural evolution was observed and analyzed at sub-100 nm resolution. It is shown quantitatively that increasing the Ni/YSZ ratio increases the Ni coarsening rate. This is due to both increased pore volume and a decrease in the YSZ volume fraction, such that there is more free volume and a less obtrusive YSZ network, both of which allow greater Ni coarsening. The results are shown to be in good agreement with a power-law coarsening model. The finding is critical for informing the design of SOFC electrode microstructures that limit coarsening and performance degradation.
Impact of MoO3 interlayer on the energy level alignment of pentacene-C60 heterostructure
Authors: Zou Ye , Mao Hongying , Meng Qing , Zhu Daoben
Published: February 2016

Using in situ ultraviolet photoelectron spectroscopy, the electronic structure evolutions at the interface between pentacene and fullerene (C60), a classical organic donor-acceptor heterostructure in organic electronic devices, on indium-tin oxide (ITO) and MoO3 modified ITO substrates have been investigated. The insertion of a thin layer MoO3 has a significant impact on the interfacial energy level alignment of pentacene-C60 heterostructure. For the deposition of C60 on pentacene, the energy difference between the highest occupied molecular orbital of donor and the lowest unoccupied molecular orbital of acceptor (HOMOD-LUMOA) offset of C60/pentacene heterostructure increased from 0.86 eV to 1.54 eV after the insertion of a thin layer MoO3 on ITO. In the inverted heterostructrure where pentacene was deposited on C60, the HOMOD-LUMOA offset of pentacene/C60 heterostructure increased from 1.32 to 2.20 eV after MoO3 modification on ITO. The significant difference of HOMOD-LUMOA offset shows the feasibility to optimize organic electronic device performance through interfacial engineering approaches, such as the insertion of a thin layer high work function MoO3 films.
Can quantum transition state theory be defined as an exact t = 0+ limit?
Authors: Jang Seogjoo , Voth Gregory A.
Published: February 2016

The definition of the classical transition state theory (TST) as a t → 0+ limit of the flux-side time correlation function relies on the assumption that simultaneous measurement of population and flux is a well defined physical process. However, the noncommutativity of the two measurements in quantum mechanics makes the extension of such a concept to the quantum regime impossible. For this reason, quantum TST (QTST) has been generally accepted as any kind of quantum rate theory reproducing the TST in the classical limit, and there has been a broad consensus that no unique QTST retaining all the properties of TST can be defined. Contrary to this widely held view, Hele and Althorpe (HA) [J. Chem. Phys. 138, 084108 (2013)] recently suggested that a true QTST can be defined as the exact t → 0+ limit of a certain kind of quantum flux-side time correlation function and that it is equivalent to the ring polymer molecular dynamics (RPMD) TST. This work seeks to question and clarify certain assumptions underlying these suggestions and their implications. First, the time correlation function used by HA as a starting expression is not related to the kinetic rate constant by virtue of linear response theory, which is the first important step in relating a t = 0+ limit to a physically measurable rate. Second, a theoretical analysis calls into question a key step in HA’s proof which appears not to rely on an exact quantum mechanical identity. The correction of this makes the true t = 0+ limit of HA’s QTST different from the RPMD-TST rate expression, but rather equal to the well-known path integral quantum transition state theory rate expression for the case of centroid dividing surface. An alternative quantum rate expression is then formulated starting from the linear response theory and by applying a recently developed formalism of real time dynamics of imaginary time path integrals [S. Jang, A. V. Sinitskiy, and G. A. Voth, J. Chem. Phys. 140, 154103 (2014)]. It is shown that the t → 0+ limit of the new rate expression vanishes in the exact quantum limit.
A class of circular waveguiding structures containing cylindrically anisotropic metamaterials: Applications from radio frequency/microwave to optical frequencies
Authors: Pollock Justin G. , Iyer Ashwin K. , Pratap Dheeraj , Anantha Ramakrishna S.
Published: February 2016

This paper investigates a class of circular waveguiding structures containing anisotropic metamaterials and explores their potential benefits in applications from RF to optical frequencies. The introduction of anisotropy in these waveguides is shown to provide substantial control of the dispersion and field distributions of several supported modes. For exotic material parameters such as permittivity and permeability that are typically associated with metamaterials, intriguing propagation phenomena such as backward-wave behavior, frequency-reduced modes, monomodal propagation, and field confinement are observed and provide enabling functionalities for a wide range of RF/microwave and optical applications.
Features of primary damage by high energy displacement cascades in concentrated Ni-based alloys
Authors: Béland Laurent Karim , Lu Chenyang , Osetskiy Yuri N. , Samolyuk German D. , Caro Alfredo , Wang Lumin , Stoller Roger E.
Published: February 2016

Alloying of Ni with Fe or Co has been shown to reduce primary damage production under ion irradiation. Similar results have been obtained from classical molecular dynamics simulations of 1, 10, 20, and 40 keV collision cascades in Ni, NiFe, and NiCo. In all cases, a mix of imperfect stacking fault tetrahedra, faulted loops with a 1/3⟨111⟩ Burgers vector, and glissile interstitial loops with a 1/2⟨110⟩ Burgers vector were formed, along with small sessile point defect complexes and clusters. Primary damage reduction occurs by three mechanisms. First, Ni-Co, Ni-Fe, Co-Co, and Fe-Fe short-distance repulsive interactions are stiffer than Ni-Ni interactions, which lead to a decrease in damage formation during the transition from the supersonic ballistic regime to the sonic regime. This largely controls final defect production. Second, alloying decreases thermal conductivity, leading to a longer thermal spike lifetime. The associated annealing reduces final damage production. These two mechanisms are especially important at cascades energies less than 40 keV. Third, at the higher energies, the production of large defect clusters by subcascades is inhibited in the alloys. A number of challenges and limitations pertaining to predictive atomistic modeling of alloys under high-energy particle irradiation are discussed.
Correlative theoretical and experimental investigation of the formation of AlYB14 and competing phases
Authors: Hunold Oliver , Chen Yen-Ting , Music Denis , Persson Per O. Å. , Primetzhofer Daniel , to Baben Moritz , Achenbach Jan-Ole , Keuter Philipp , Schneider Jochen M.
Published: February 2016

The phase formation in the boron-rich section of the Al-Y-B system has been explored by a correlative theoretical and experimental research approach. The structure of coatings deposited via high power pulsed magnetron sputtering from a compound target was studied using elastic recoil detection analysis, electron energy loss spectroscopy spectrum imaging, as well as X-ray and electron diffraction data. The formation of AlYB14 together with the (Y,Al)B6 impurity phase, containing 1.8 at. % less B than AlYB14, was observed at a growth temperature of 800 °C and hence 600 °C below the bulk synthesis temperature. Based on quantum mechanical calculations, we infer that minute compositional variations within the film may be responsible for the formation of both icosahedrally bonded AlYB14 and cubic (Y,Al)B6 phases. These findings are relevant for synthesis attempts of all boron rich icosahedrally bonded compounds with the space group: Imma that form ternary phases at similar compositions.
Force transfer characteristics of composite bucket foundation for offshore wind turbines
Authors: Zhang Puyang , He Shaohua , Liu Yonggang , Ding Hongyan
Published: February 2016

This paper presents a new type of composite bucket foundation (CBF) for offshore wind turbines, which can be adapted to the loading characteristics and development needs of offshore wind farms due to its special structural form. There are seven rooms divided inside the CBF by steel bulkheads, which are arranged in a honeycomb structure. The six peripheral rooms with the skirt have the same proportions while the middle orthohexagonal one is a little larger. With the seven-room structure, the CBF has reasonable motion characteristics and towing reliability during the wet-tow construction process. Through extensive research into the force transfer characteristics of composite structure systems, a composite bucket foundation structure system with a curved transition part has been developed. The large bending moment and horizontal force of the wind turbine tower are transferred to and dispersed into the sea floor soil through a prestressed curved concrete transition section, the top cover of the bucket foundation, the bucket skirts, and the internal steel compartment plates. Particularly, this proposed CBF structure can effectively convert the extremely large bending moment of the turbine tower to limited tensile and compressive stresses within the foundation structure via a transition section.
Space matters: Li+ conduction versus strain effect at FePO4/LiFePO4 interface
Authors: Lv Weiqiang , Niu Yinghua , Jian Xian , Zhang Kelvin H. L. , Wang Wei , Zhao Jiyun , Wang Zhiming , Yang Weiqing , He Weidong
Published: February 2016

FePO4/LiFePO4 (FP/LFP) interfacial strain, giving rise to substantial variation in interfacial energy and lattice volume, is inevitable in the (de)lithiation process of LiFePO4, a prototype of Li ion battery cathodes. Extensive theoretical and experimental research has been focused on the effect of lattice strain energy on FP/LFP interface propagation orientation and cyclic stability of the electrode. However, the essential effect of strain induced lattice distortion on Li+ transport at the FP/LFP interface is typically overlooked. In this report, a coherent interface model is derived to evaluate quantitatively the correlation between FP/LFP lattice distortion and Li+ conduction. The results illustrate that the effect of lattice strain on Li+ conduction depends strongly on FP/LFP interface orientations. Lattice strain induces a 90% decrease of Li+ conductivity in ac-plane oriented (de)lithiation at room temperature. The opposite effect of lattice strain on delithiation and lithiation for ab- and bc-orientations is elucidated. In addition, the effect of lattice strain tends to be more pronounced at a lower working temperature. This study provides an efficient platform to comprehend and manipulate Li+ conduction in the charge and discharge of lithium ion batteries, the large-scale application of which is frequently challenged by limited in-cell ion conduction.
Generation of micro-sized PDMS particles by a flow focusing technique for biomicrofluidics applications
Authors: Muñoz-Sánchez B. N. , Silva S. F. , Pinho D. , Vega E. J. , Lima R.
Published: February 2016

Polydimethylsiloxane (PDMS), due to its remarkable properties, is one of the most widely used polymers in many industrial and medical applications. In this work, a technique based on a flow focusing technique is used to produce PDMS spherical particles with sizes of a few microns. PDMS precursor is injected through a hypodermic needle to form a film/reservoir over the needle's outer surface. This film flows towards the needle tip until a liquid ligament is steadily ejected thanks to the action of a coflowing viscous liquid stream. The outcome is a capillary jet which breaks up into PDMS precursor droplets due to the growth of capillary waves producing a micrometer emulsion. The PDMS liquid droplets in the solution are thermally cured into solid microparticles. The size distribution of the particles is analyzed before and after curing, showing an acceptable degree of monodispersity. The PDMS liquid droplets suffer shrinkage while curing. These microparticles can be used in very varied technological fields, such as biomedicine, biotechnology, pharmacy, and industrial engineering.
Nutrition of antler growth in deer
Authors: Dryden G. McL.
Published: February 2016

Stags are susceptible to the effects of nutrition at several stages during their lives and during the antler cycle. Nutrition during the in utero, post-natal (suckling) and yearling stages influences the size of spike antlers, and, generally, there is a close relationship between bodyweight and antler weight in stags aged up to 5 years. While antler size is not greatly affected by nutrition during the growth of immature (velvet) antler, it is influenced by body size and condition at casting, i.e. at the beginning of new antler growth. Antler growth appears to have a high priority for nutrients, especially energy, protein and calcium. Antler growth in adult stags is little affected by diet protein concentrations over 7%, but supplements of protected protein or methionine may improve antler growth. Substantial amounts of calcium and phosphorus are sequestered in antlers as they become mineralised, and calcium is withdrawn from the skeleton in support of this. Feeding programs to obtain good antler growth involve recognising the periods when juvenile stags are susceptible to under-nutrition, and providing sufficient nutrients to re-establish adequate body condition in adult stags between the end of the rut and antler casting.
Total velvet-antler polypeptide extract from Cervus nippon Temminck induces cell proliferation and activation of the PI3K–Akt signalling pathway in human peripheral blood lymphocytes
Authors: Zhang Min , Li Na , Qu Xiao Bo , Luo Su , Drummen Gregor P. C.
Published: February 2016

Velvet antler (VA) has been used for centuries as a traditional medicine to treat a wide range of health problems. VA was first recorded in the Chinese medical classics Shen Nong Ben Cao Jing 2000 years ago. VA has been extensively used to strengthen bones and muscles, promote blood flow and increase immune function. In the present study, we used VA (Cervus nippon Temminck) protein extract (VAPE) to induce cell proliferation and differentiation in human peripheral blood lymphocyte cell line 1301 cells. The results showed that 100 µg/mL of VAPE could significantly induce 1301-cell proliferation (151.3%), increase the population of S-phase cells and increase the expression of CDK4. In addition, VAPE could effectively increase the expression levels of PI3K and Akt and activate PI3K–Akt signal pathway. These findings have provided novel insights into the further understanding of the molecular and signalling pathway mechanisms of VAPE in promoting proliferation of human peripheral blood lymphocyte cells.
Micromanipulation of equine blastocysts to allow vitrification
Authors: Hinrichs Katrin , Choi Young-Ho
Published: February 2016

Embryo cryopreservation presents an essential method for banking of valuable genetics. However, in equine species the cryopreservation of embryos is complicated by three interacting factors: (1) the late entry of the embryo into the uterus (~6 days after ovulation); (2) the rapid expansion of the blastocyst; and (3) the formation of the equine embryonic capsule, a glycoprotein membrane that forms between the embryo and zona. Efforts to freeze or vitrify equine expanded blastocysts were initially met with little success. In addition, it was thought that breaching the capsule led to loss of embryo viability. We found that micromanipulation with the Piezo drill to puncture the capsule and collapse the blastocyst before vitrification provided a means for successful cryopreservation of equine expanded blastocysts, and that this can be done successfully using a standard sperm injection pipette. Modification of cryoprotectants and methods for vitrification and warming resulted in a technique that allowed successful vitrification of expanded equine blastocysts up to 650 µm diameter, with pregnancy rates approaching those for fresh embryos. After blastocyst collapse, vitrification is performed with ethylene glycol and galactose as cryoprotectants, and the embryo is cooled in a low-volume micropipette tip. Vitrification of expanded equine blastocysts provides a valuable tool for use in exotic equids to preserve genetics.
Spheres, Rings, and Rods as Electrodes in Electrofishing: Their Effects on System Resistance and Electrical Fields
Authors: Reynolds James B.
Published: February 2016

Three shapes of electrodes are used for most electrofishing: spheres, rings, and rods. The predictive value of theoretical equations and relative effects of electrode size, shape, and stock diameter (material thickness) on electrical characteristics have not been evaluated by designed experiment. I performed an experiment in a hatchery raceway, using minimum and maximum electrode size‐shape categories common in electrofishing: 15‐cm‐ and 30‐cm‐diameter spheres and rings and 48‐cm‐ and 96‐cm‐long rods (lengths equivalent to ring circumferences). Each size of ring and rod was fabricated in four stock diameters: 3, 6, 10, and 13 mm. Eighteen identical pairs of electrodes (two spheres, eight rings, eight rods) were energized with 120‐V, 60‐Hz sine‐wave AC. Observed values of system resistance (representing potential power demand), voltage gradient at 0–1 cm from an electrode surface (high‐hazard zone for fish), and distance to 0.1 V/cm (effective field size) were measured. Both size–shape and stock diameter had highly significant (P ≤ 0.01) effects on system resistance, high‐hazard zone, and effective field size. Size–shape effect was about nine times more important than stock diameter in its influence on system resistance; about six times more for effective field size; and about twice more for the high‐hazard zone. Boundary conditions imposed by the raceway limited the usefulness of theoretical equations; such boundaries would also exist in natural waters. Empirical measurements of circuits and fields are more accurate and realistic, than theoretical values, for application of electrode design. Lacking one's own empirical data, the data from this study may be used to test virtual electrofishing systems for electrode design. Scenarios are offered as examples for practical application of the results of this study.

Received November 25, 2014; accepted October 13, 2015
Substance use among Persons with Homeless Experience in Primary Care
Authors: Stringfellow Erin J. , Kim Theresa W. , Gordon Adam J. , Pollio David E. , Grucza Richard A. , Austin Erika L. , Johnson N. Kay , Kertesz Stefan G.
Published: February 2016

Background: Community survey data suggest high prevalence of substance use disorders among currently homeless individuals. There are less data regarding illicit drug and alcohol use problems of homeless-experienced persons engaged in primary care. They may have less severe use and require different care responses from primary care teams. Methods: The authors surveyed currently and formerly homeless, i.e., homeless-experienced, persons engaged in primary care at five federally funded programs in the United States, administering the World Health Organization (WHO) Alcohol, Smoking and Substance Involvement Screening Test (ASSIST). The ASSIST definitions of lower, moderate, and high risk were used to assess a spectrum of lifetime and recent substance use, from any use to likely dependence, and to identify sociodemographic and health status characteristics associated with severity of use. Results: Almost one half of the sample ( N = 601) had recently (within the past three months) used alcohol, and one third had recently used an illicit drug. The most commonly used illicit drugs in the past three months were cannabis (19%), cocaine (16%), and opioids (7.5%). Over one half (59%) of respondents had ASSIST-defined moderate- or high-risk substance use. A significant proportion (31%) of those identified as at moderate risk had no recent substance use, but did report past problematic use. Ten percent of the lower-risk group had past problematic use of alcohol. Severity of use was associated with worse health status, but not with housing status or type of homelessness experienced. Conclusions: Less severe (moderate-risk) use and past problematic use, potentially indicative of remitted substance use disorders, were more common than high-risk use in this primary care, homeless-experienced sample. These findings highlight the urgency of identifying effective ways to reduce risky substance use and prevent relapse in homeless-experienced persons.
Factors Associated with Buprenorphine versus Methadone use in Pregnancy
Authors: Krans Elizabeth E. , Bogen Debra , Richardson Gale , Park Seo Young , Dunn Shannon L. , Day Nancy
Published: February 2016

Background: Buprenorphine has recently emerged as a safe and effective treatment option for pregnant women with opioid use disorder (OUD) and is associated with superior neonatal outcomes. This study characterized and compared patient populations who used buprenorphine versus methadone during pregnancy in an academic medical center. Methods: Observational retrospective cohort evaluation of 791 pregnant women with OUD on opioid maintenance treatment from 2009 to 2012. Buprenorphine versus methadone use was defined as use after either (a) conversion from illicit opioid use during pregnancy or (b) ongoing prepregnancy use. Multivariable logistic regression was used to identify patient characteristics predictive of buprenorphine use. Results: Among 791 pregnant women, 608 (76.9%) used methadone and 183 (23.1%) used buprenorphine. From 2009 to 2012, buprenorphine use during pregnancy increased from 10.1% to 33.2%. Pregnant women using buprenorphine were significantly more likely to be older, married, employed, have more education, and have a history of prescription opioid use compared with women using methadone. In contrast, pregnant women using methadone were significantly more likely to have hepatitis C virus infection, use cocaine, benzodiazepines, or marijuana, and have a history of heroin and/or intravenous opioid use. In multivariable analysis, pregnant women who were older (odds ratio [OR] = 1.01; 95% confidence interval [CI]: 1.02, 1.11), were employed (1.87; 1.20, 2.90), and had a history of opioid maintenance treatment prior to pregnancy (2.68; 1.78, 4.02) were more likely to use buprenorphine during pregnancy. Pregnant women with a history of benzodiazepine use (0.48; 0.30, 0.77), who had children no longer in their legal custody (0.63; 0.40, 0.99), and who had a partner with a substance use history (0.37; 0.22, 0.63) were less likely to use buprenorphine during pregnancy. Conclusions: Disparities exist among patients who use buprenorphine versus methadone during pregnancy and indicate the need to improve the availability and accessibility of buprenorphine for many pregnant women.
Measuring residual stresses in linear friction welded joints composed by dissimilar titanium
Authors: Xie P. , Zhao H. , Liu Y.
Published: February 2016

The Ti–5Al–2Sn–2Zr–4Mo–4Cr (Ti17) titanium alloy is the main material used in manufacturing blades and disks of aero engines, and it is always jointed with different microstructures for the design constraints. In this work, the residual stresses of linear friction welding of β Ti17 and α + β Ti17 are measured by contour method and the X-ray diffraction method. The welding-induced tensions were found to be greater on the β side than that on the α + β side, and had an obvious reduction in the weld centre. After the post weld heat treatment (PWHT) of 630°C for 3 h, all tensions on the β side relax to a very limited value while some new PWHT-induced compressions are found on the α + β side.
Study on residual stress in socket weld by numerical simulation and experiment
Authors: Wang H. , Jing H. Y. , Zhao L. , Han Y. D. , Xu L. Y.
Published: February 2016

In this paper, welding residual stress in socket weld of 304L stainless steel pipe was investigated using numerical simulation and validated by X-ray stress measurement. From the simulation results, the maximum tensile residual stresses were located at weld root and weld toe on both sides of the weld along pipe, which led to the fatigue failure. Pre-bevelling and low transformation temperature (LTT) dressing could decrease tensile residual stress both in hoop and axial direction at weld root and weld toe. After LTT dressing, compressive residual stress was generated throughout weld toe. Compressive stress can delay fatigue crack initiation and propagation. Therefore, pre-bevelling and LTT dressing can improve the fatigue life of socket weld.
Regular del Pezzo surfaces with irregularity
Authors: Maddock Zachary
Published: February 2016

We construct the first examples of regular del Pezzo surfaces

X
X

for which ℎ¹(𝒪

_{𝒳})>0.

We also find a restriction on the integer pairs that are possible as the anti-canonical degree

K
X
2

K_X^2

and irregularity

h
1

(

O

X

)

h^1(\mathcal {O}_X)

of such a surface. Our method of proof is by generalizing results of Ekedahl on foliations to the setting of regular varieties.
A theoretical model of cytokinesis implicates feedback between membrane curvature and cytoskeletal organization in asymmetric cytokinetic furrowing
Authors: Dorn Jonas F. , Zhang Li , Phi Tan-Trao , Lacroix Benjamin , Maddox Paul S. , Liu Jian , Maddox Amy Shaub
Published: February 2016

During cytokinesis, the cell undergoes a dramatic shape change as it divides into two daughter cells. Cell shape changes in cytokinesis are driven by a cortical ring rich in actin filaments and nonmuscle myosin II. The ring closes via actomyosin contraction coupled with actin depolymerization. Of interest, ring closure and hence the furrow ingression are nonconcentric (asymmetric) within the division plane across Metazoa. This nonconcentricity can occur and persist even without preexisting asymmetric cues, such as spindle placement or cellular adhesions. Cell-autonomous asymmetry is not explained by current models. We combined quantitative high-resolution live-cell microscopy with theoretical modeling to explore the mechanistic basis for asymmetric cytokinesis in the Caenorhabditis elegans zygote, with the goal of uncovering basic principles of ring closure. Our theoretical model suggests that feedback among membrane curvature, cytoskeletal alignment, and contractility is responsible for asymmetric cytokinetic furrowing. It also accurately predicts experimental perturbations of conserved ring proteins. The model further suggests that curvature-mediated filament alignment speeds up furrow closure while promoting energy efficiency. Collectively our work underscores the importance of membrane–cytoskeletal anchoring and suggests conserved molecular mechanisms for this activity.
Is the higher rate of parental child homicide in stepfamilies an effect of non-genetic relatedness?
Authors: Temrin Hans , Nordlund Johanna , Rying Mikael , Tullberg Birgitta S.
Published: February 2016

In an evolutionary perspective individuals are expected to vary the degree of parental love and care in relation to the fitness value that a child represents. Hence, stepparents are expected to show less solicitude than genetically related parents, and this lack of genetic relatedness has been used to explain the higher frequencies of child abuse and homicide found in stepfamilies. However, other factors than non-genetic relatedness may cause this over-representation in stepfamilies. Here we use a 45-year data set of parental child homicides in Sweden to test two hypotheses related to the higher incidence in stepfamilies: 1) adults in different types of family differ in their general disposition to use violence, and 2) parents are more likely to kill stepchildren than genetically related children. Of the 152 perpetrators in biparental families there was an overrepresentation of perpetrators in step-families (n=27) compared with the general population. We found support for the first hypothesis in that both general and violent crime rates were higher in stepfamilies, both in the general population and among perpetrators of child homicide. However, we found no support for the second hypothesis because of the 27 perpetrators in stepfamilies the perpetrator killed a genetically related child in 13 cases, a stepchild in 13 cases and both types of children in one case. Moreover, out of the 12 families where the perpetrator lived with both stepchildren and genetic children, there was no bias towards killing stepchildren. Thus, we found no evidence for an effect of non-genetic relatedness per se.
Behavioral and life history responses to extreme climatic conditions: Studies on a migratory songbird
Authors: Møller A. P.
Published: February 2016

Behavioral responses to environmental change are the mechanisms that allow for rapid phenotypic change preventing temporary or permanent damage and hence preventing reductions in fitness. Extreme climatic events are by definition rare, although they are predicted to increase in amplitude and frequency in the coming years. However, our current knowledge about behavioral responses to such extreme events is scarce. Here I analyze two examples of the effects of extreme weather events on behavior and life history: (1) A comparison of behavior and life history during extremely warm and extremely cold years relative to normal years; and (2) a comparison of behavior before and after the extremely early snowfall in fall 1974 when numerous birds died in the Alps during September-October. Behavioral and life history responses of barn swallows Hirundo rustica to extremely cold and extremely warm years were positively correlated, with particularly large effect sizes in cold years. Extreme mortality in barn swallows during fall migration 1974 in the Alps eliminated more than 40% of the breeding population across large areas in Central and Northern Europe, and this affected first arrival date, changes in timing and extent of reproduction and changes in degree of breeding sociality supposedly as a consequence of correlated responses to selection. Finally, I provide directions for research that will allow us to better understand behavior and life history changes in response to extreme climate change.
What are extreme environmental conditions and how do organisms cope with them?
Authors: Wingfield John C. , Kelley J. Patrick , Angelier Frédéric
Published: February 2016

Severe environmental conditions affect organisms in two major ways. The environment may be predictably severe such as in deserts, polar and alpine regions, or individuals may be exposed to temporarily extreme conditions through weather, presence of predators, lack of food, social status etc. Existence in an extreme environment may be possible, but then to breed or molt in addition can present major bottlenecks that have resulted in the evolution of hormone-behavior adaptations to cope with unpredictable events. Examples of hormone-behavior adaptations in extreme conditions include attenuated testosterone secretion because territoriality and excess courtship may be too costly when there is one opportunity to reproduce. The individual may even become insensitive to testosterone when target areas of the brain regulating reproductive behavior no longer respond to the hormone. A second example is reduced sensitivity to glucocorticoids following acute stress during the breeding season or molt that allows successful reproduction and/or a vital renewal of the integument to endure extreme conditions during the rest of the year. Reduced sensitivity could involve: (a) modulated response of the hypothalamo-pituitary-adrenal axis, (b) reduced sensitivity to high glucocorticoid levels, or (c) a combination of (a) and (b). Moreover, corticosteroid binding proteins (CBP) buffer responses to stress by reducing the movement of glucocorticoids into target cells. Finally, intracellular enzymes (11β-hydroxysteroid dehydrogenase and variants) can deactivate glucocorticoids entering cells thus reducing interaction with receptors. These mechanisms have important implications for climate change and increasing extremes of weather.
Short- and long-term effects of developmental corticosterone exposure on avian physiology, behavioral phenotype, cognition, and fitness: A review
Authors: Schoech Stephan J. , Rensel Michelle A. , Heiss Rebecca S.
Published: February 2016

A growing body of evidence from across taxa suggests that exposure to elevated levels of glucocorticoids during early development can have long-term effects upon physiological and behavioral phenotypes. Additionally, there is some, though limited, evidence that similar early exposure can also negatively impact cognitive ability. Following pioneering mammalian studies, several avian studies have revealed that the responsiveness of the hypothalamo-pituitary-adrenal (HPA) axis as an adult can be explained by levels of corticosterone, the avian glucocorticoid, the individual experienced as a nestling or even as an embryo via yolk exposure. Studies also suggest that perinatal exposure to corticosterone can have effects upon avian ‘personalities’ or coping styles, and findings from mammalian studies suggest that these long-term effects are mediated epigenetically via altered expression of relevant DNA sequences. Although a consistent pattern across-species has yet to emerge, recent work in Florida scrub-jays Aphelocoma coerulescens found that baseline corticosterone levels in 11-day-old nestlings explained 84% of the variation in ‘personality’ (bold vs. timid) when those individuals were tested approximately seven months later. Nestlings with elevated corticosterone levels were more timid than those individuals that as nestlings experienced relatively low corticosterone levels. Some researchers have suggested that parents might use such mechanisms to ‘program’ their offsprings’ phenotype to best fit prevailing environmental conditions. This review will visit what is known about the links between stressful developmental conditions that result in exposure to elevated corticosterone and the short- and long-term effects of this steroid hormone upon central nervous system function and whether alterations thereof are beneficial, deleterious, or neutral. It will concentrate on examples from birds, although critical supporting studies from the mammalian literature will be included as appropriate.
Limited gene flow and partial isolation phylogeography of Himalayan snowcock Tetraogallus himalayensis based on part mitochondrial D-loop sequences
Authors: Wang Xiaoli , Qu Jiangyong , Liu Naifa , Bao Xinkang , Song Sen
Published: February 2016

Himalayan snowcock Tetraogallus himalayensis are distributed in alpine and subalpine areas in China. We used mitochondrial DNA control-region data to investigate the origin and past demographic change in sixty-seven Himalayan snowcock T. himalayensis. The fragments of 1155 nucleotides from the control region of mitochondrial DNA were sequenced, and 57 polymorphic positions defined 37 haplotypes. A high level of genetic diversity was detected in all populations sampled and may be associated isolation of the mountains and habitat fragmentation and deterioration from Quaternary glaciations. In the phylogenetic tree, all haplotypes grouped into four groups: clade A (Kunlun Mountains clade), clade B (Northern Qinghai-Tibetan Plateau clade), clade C (Tianshan Mountains clade) and clade D (Kalakunlun Mountains clade). We found a low level of gene flow and significant genetic differentiation among all populations. Based on divergence time we suggest that the divergence of Himalayan snowcock occurred in the middle Pleistocene inter-glaciation, and expansion occurred in the glaciation. Analysis of mtDNA D-loop sequences confirmed demographic population expansion, as did our non-significant mismatch distribution analysis. In conclusion, limited gene flow and a pattern of partial isolation phylogeographic was found in geographic populations of T. himalayansis based on the analysis on mtDNA D-loop sequences.