bluuebunny/crossref_metadata_2025 huggingface dataset:
Pressure‐induced structural transition of mature HIV‐1 protease from a combined NMR/MD simulation approach
Authors: Roche Julien , Louis John M. , Bax Ad , Best Robert B.
Published: September 2015

We investigate the pressure‐induced structural changes in the mature human immunodeficiency virus type 1 protease dimer, using residual dipolar coupling (RDC) measurements in a weakly oriented solution. 1DNH RDCs were measured under high‐pressure conditions for an inhibitor‐free PR and an inhibitor‐bound complex, as well as for an inhibitor‐free multidrug resistant protease bearing 20 mutations (PR20). While PR20 and the inhibitor‐bound PR were little affected by pressure, inhibitor‐free PR showed significant differences in the RDCs measured at 600 bar compared with 1 bar. The structural basis of such changes was investigated by MD simulations using the experimental RDC restraints, revealing substantial conformational perturbations, specifically a partial opening of the flaps and the penetration of water molecules into the hydrophobic core of the subunits at high pressure. This study highlights the exquisite sensitivity of RDCs to pressure‐induced conformational changes and illustrates how RDCs combined with MD simulations can be used to determine the structural properties of metastable intermediate states on the folding energy landscape. Proteins 2015; 83:2117–2123. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Standardized Prunella vulgaris var. lilacina Extract Enhances Cognitive Performance in Normal Naive Mice
Authors: Park Se Jin , Ahn Young Je , Lee Hyung Eun , Hong Eunyoung , Ryu Jong Hoon
Published: September 2015

Adult hippocampal neurogenesis is closely associated with neuronal plasticity, cognitive function and the etiology of neurological diseases. We previously reported that the standardized ethanolic extract of Prunella vulgaris var. lilacina (EEPV) can be used for the prevention and treatment of cognitive impairments associated with Alzheimer's disease or schizophrenia. In the present study, we investigated the effects of EEPV on cognitive ability in normal naive mice and the underlying mechanism(s) governing these effects, including adult hippocampal neurogenesis. In the passive avoidance task, sub‐chronic administration of EEPV (25 or 50 mg/kg, p.o.) for 14 days markedly induced the improvement of cognitive function in mice. In addition, sub‐chronic administration of EEPV (25 or 50 mg/kg) for 14 days significantly increased neural cell proliferation and the number of immature neurons, but not newly generated cell survival, in the hippocampal dentate gyrus. Increased ERK, Akt and GSK‐3β phosphorylation levels in the hippocampus were also observed after such administration. Our results indicate that EEPV may enhance cognitive function via the activation of various intracellular signaling molecules and the up‐regulation of adult hippocampal neurogenesis. Copyright © 2015 John Wiley & Sons, Ltd.
Optimal control of multi‐hop control networks based on the MLD framework
Authors: Kobayashi Koichi , Hiraishi Kunihiko
Published: September 2015

A multi‐hop control network (MHCN) is a control system in which plants and controllers are connected through a multi‐hop wireless network modeled by a directed graph. In this paper, based on the MLD (mixed logical dynamical) framework, which is one of the powerful methods in hybrid systems control, we propose a modeling method and an optimal control method of MHCNs. First, a directed graph in MHCNs and a switch of the control input are modeled by a pair of a linear state equation and a linear inequality with binary variables. Thus, the MLD model expressing a given MHCN is derived. Next, using the MLD model, the optimal control problem is transformed into a mixed integer quadratic programming problem. Finally, numerical examples are presented. The proposed method provides us a basic result for control of MHCNs. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
p53‐Based strategy to reduce hematological toxicity of chemotherapy: A proof of principle study
Authors: Ha Chul S. , Michalek Joel E. , Elledge Richard , Kelly Kevin R. , Ganapathy Suthakar , Su Hang , Jenkins Carol A. , Argiris Athanassios , Swords Ronan , Eng Tony Y. , Karnad Anand , Crownover Richard L. , Swanson Gregory P. , Goros Martin , Pollock Brad H. , Yuan Zhi-Min
Published: September 2015

p53 activation is a primary mechanism underlying pathological responses to DNA damaging agents such as chemotherapy and radiotherapy. Our recent animal studies showed that low dose arsenic (LDA)‐induced transient p53 inhibition selectively protected normal tissues from chemotherapy‐induced toxicity.

Study objectives were to: 1) define the lowest safe dose of arsenic trioxide that transiently blocks p53 activation in patients and 2) assess the potential of LDA to decrease hematological toxicity from chemotherapy.

Patients scheduled to receive minimum 4 cycles of myelosuppressive chemotherapy were eligible. For objective 1, dose escalation of LDA started at 0.005 mg/kg/day for 3 days. This dose satisfied objective 1 and was administered before chemotherapy cycles 2, 4, and 6 for objective 2. p53 level in peripheral lymphocytes was measured on day 1 of each cycle by ELISA assay. Chemotherapy cycles 1, 3, and 5 served as the baseline for the subsequent cycles of 2, 4, and 6 respectively. If p53 level for the subsequent cycle was lower (or higher) than the baseline cycle, p53 was defined as “suppressed” (or “activated”) for the pair of cycles. Repeated measures linear models of CBC in terms of day, cycle, p53 activity and interaction terms were used.

Twenty‐six patients treated with 3 week cycle regimens form the base of analyses. The mean white blood cell, hemoglobin and absolute neutrophil counts were significantly higher in the “suppressed” relative to the “activated” group.

These data support the proof of principle that suppression of p53 could lead to protection of bone marrow in patients receiving chemotherapy.

This trial is registered in ClinicalTrials.gov. Identifier: NCT01428128.
Executive summary of the CAEP 2014 Academic Symposium: How to make research succeed in your department
Authors: Stiell Ian G. , Artz Jennifer D. , Perry Jeffrey , Vaillancourt Christian , Calder Lisa
Published: September 2015

The vision of the recently created Canadian Association of Emergency Physicians (CAEP) Academic Section is to promote high-quality emergency patient care by conducting world-leading education and research in emergency medicine. The Academic Section plans to achieve this goal by enhancing academic emergency medicine primarily at Canadian medical schools and teaching hospitals. It seeks to foster and develop education, research, and academic leadership amongst Canadian emergency physicians, residents, and students. In this light, the Academic Section began in 2013 to hold the annual Academic Symposia to highlight best practices and recommendations for the three core domains of governance and leadership, education scholarship, and research. Each year, members of three panels are asked to review the literature, survey and interview experts, achieve consensus, and present their recommendations at the Symposium (2013, Education Scholarship; 2014, Research; and 2015, Governance and Funding).

Research is essential to medical advancement. As a relatively young specialty, emergency medicine is rapidly evolving to adapt to new diagnostic tools, the challenges of crowding in emergency departments, and the growing needs of emergency patients. There is significant variability in the infrastructure, support, and productivity of emergency medicine research programs across Canada. All Canadians benefit from an investigation of the means to improve research infrastructure, training programs, and funding opportunities. Such an analysis is essential to identify areas for improvement, which will support the expansion of emergency medicine research. To this end, physician-scientist leaders were gathered from across Canada to develop pragmatic recommendations on the improvement of emergency medicine research through a comprehensive analysis of current best practices, systematic literature reviews, stakeholder surveys, and expert interviews.
Mexican Trilogy/Trilogía Mexicana: Writing Bodies Through Five Hundred Years
Authors: Hellier-Tinoco Ruth
Published: September 2015

Fifteenth- and sixteenth-centuryMexicawriting utilized a largely pictorial system in which bodies undertaking actions (pictorial-iconic presentation) and hieroglyphic text were used to both document and communicate information. Between 2006 and 2010, one of Mexico's most renowned innovative and interdisciplinary performance ensembles, La Máquina de Teatro, worked withMexicadocuments and sculptures in the creation of itsTrilogía Mexicana(Mexican Trilogy). I discuss fragments of the performance and studio-based creative processes as they translated from the wordless fifteenth- and sixteenth-century writing into an embodied, corporeal, moving form for a twenty-first-century performance stage, specifically aiming to explore notions of memory, temporality, history, and postdramatic theatre.
A Sorcerer's Apprentice? John Weaver's Comic Muse
Authors: Semmens Richard
Published: September 2015

This paper examines John Weaver'sEssay Towards an History of Dancing(London, 1712) and hisHistory of the Mimes and Pantomimes(London, 1728). The paper will argue that comic pantomime dancing was critically central to Weaver's agenda as practitioner and writer, theorist, and historian. Modern scholarship has privileged his admittedly considerable contributions in the serious mode in ways that compromise our understanding of his important work overall.
Lactase non-persistence as a determinant of milk avoidance and calcium intake in children and adolescents
Authors: Almon Ricardo , Sjöström Michael , Nilsson Torbjörn K.
Published: September 2015

This study examines if lactase non-persistent (LNP) children and adolescents differ from those who are lactase persistent (LP) as regards milk avoidance and Ca intake. We also studied potential differences in anthropometric features related to obesity, and examined if milk avoidance is associated with lactase-persistence status. Additionally, we aimed to determine if heterozygous subjects showed an intermediary phenotype as regards Ca intake. Furthermore, we tested if LP and LNP influence vitamin D intake. The European Youth Heart Study is an ongoing international, multi-centre cohort study primarily designed to address CVD risk factors. Children (n298, mean age 9·6 years) and adolescents (n386, mean age 15·6 years) belonging to the Swedish part of the European Youth Heart Study were genotyped for the LCT-13910 C > T polymorphism. Mendelian randomisation was used. Milk avoidance was significantly more common in LNP adolescents (OR 3·2; 95% CI 1·5, 7·3). LP subjects had higher milk consumption (P < 0·001). Accordingly, energy consumption derived from milk and Ca intake was lower in LNP (P < 0·05 andP < 0·001, respectively). Heterozygous subjects did not show an intermediary phenotype concerning milk consumption. LP or LNP status did not affect vitamin D intake or anthropometric variables. LNP in children and adolescents is associated with reduced intake of milk and some milk-product-related nutritional components, in particular Ca. This reduced intake did not affect the studied anthropometric variables, indicators of body fat or estimated vitamin D intake. However, independently of genotype, age and sex, daily vitamin D intake was below the recommended intakes. Milk avoidance among adolescents but not children was associated with LNP.
Critical care for paediatric patients with heart failure
Authors: Costello John M. , Mazwi Mjaye L. , McBride Mary E. , Gambetta Katherine E. , Eltayeb Osama , Epting Conrad L.
Published: September 2015

This review offers a critical-care perspective on the pathophysiology, monitoring, and management of acute heart failure syndromes in children. An in-depth understanding of the cardiovascular physiological disturbances in this population of patients is essential to correctly interpret clinical signs, symptoms and monitoring data, and to implement appropriate therapies. In this regard, the myocardial force–velocity relationship, the Frank–Starling mechanism, and pressure–volume loops are discussed. A variety of monitoring modalities are used to provide insight into the haemodynamic state, clinical trajectory, and response to treatment. Critical-care treatment of acute heart failure is based on the fundamental principles of optimising the delivery of oxygen and minimising metabolic demands. The former may be achieved by optimising systemic arterial oxygen content and the variables that determine cardiac output: heart rate and rhythm, preload, afterload, and contractility. Metabolic demands may be decreased by a number of ways including positive pressure ventilation, temperature control, and sedation. Mechanical circulatory support should be considered for refractory cases. In the near future, monitoring modalities may be improved by the capture and analysis of complex clinical data such as pressure waveforms and heart rate variability. Using predictive modelling and streaming analytics, these data may then be used to develop automated, real-time clinical decision support tools. Given the barriers to conducting multi-centre trials in this population of patients, the thoughtful analysis of data from multi-centre clinical registries and administrative databases will also likely have an impact on clinical practice.
Echocardiographic evaluation of the failing heart
Authors: Parthiban Anitha , Shirali Girish
Published: September 2015

Heart failure in children can result from a wide range of aetiologies and can manifest in systolic and/or diastolic dysfunction. Echocardiography is the primary test for the diagnosis and follow-up of children with heart failure. In this article, we critically review standard echocardiographic measurements that have been shown to have prognostic importance in children with various types of heart failure. Each of the common forms of cardiomyopathy that is encountered in childhood – dilated, hypertrophic, restrictive, left ventricular non-compaction, and arrhythmogenic right ventricular cardiomyopathy – is discussed separately. Special attention is paid to the failing right ventricle, both in the systemic and in the sub-pulmonary position, to the failing univentricular heart, and to the assessment of diastolic function in children.
Entekhabi Receives 2015 Hydrologic Sciences Award
Authors:   AGU
Published: September 2015

Dara Entekhabi will receive the 2015 Hydrologic Sciences Award at the 2015 American Geophysical Union Fall Meeting, to be held 14–18 December in San Francisco, Calif. The award is for outstanding contributions to the science of hydrology.
Gleeson Receives 2015 Early Career Hydrologic Science Award
Authors:   AGU
Published: September 2015

Thomas Gleeson will receive the 2015 Early Career Hydrologic Science Award at the 2015 American Geophysical Union Fall Meeting, to be held 14–18 December in San Francisco, Calif. The award is for significant early career contributions to hydrologic science.
Riding a "Roller Coaster" at National Geographic
Authors: Wei-Haas Maya
Published: September 2015

Ph.D. geologist loves doing science, but a summer gig chasing news and explaining the science behind it touches her storytelling heart.
Engineering Climate Change Resilience into New York Subways
Authors: Lemonick Sam
Published: September 2015

Impending renovations presented at a conference on transportation systems and climate extremes would keep hurricane-driven waters out of subsurface transit tunnels.
Effects of post-suckling n-3 polyunsaturated fatty acids: prevention of dyslipidemia and liver steatosis induced in rats by a sucrose-rich diet during pre- and post-natal life
Authors: Chicco Adriana , Creus Agustina , Illesca Paola , Hein Gustavo Juan , Rodriguez Silvia , Fortino Alejandra
Published: September 2015

After suckling, dietary fish oil (FO) that is rich in n-3 PUFAs attenuates induced sucrose outcomes.
Watson–Crick base pairing, electronic and photophysical properties of triazole modified adenine analogues: a computational study
Authors: Das Shubhajit , Samanta Pralok K , Pati Swapan K
Published: September 2015

Triazole adenine nucleobase analogues show fluorescence in the UV-Vis region and form Watson–Crick base pairing with thymine nucleobases.
Synthesis of a fluorinated Ezetimibe analogue using radical allylation of α-bromo-α-fluoro-β-lactam
Authors: Tarui Atsushi , Tanaka Ayumi , Ueo Masakazu , Sato Kazuyuki , Omote Masaaki , Ando Akira
Published: September 2015

A facile and efficient synthesis of a fluorinated Ezetimibe analogue was achieved by radical allylation, Wacker oxidation, and nucleophilic arylation of α-bromo-α-fluoro-β-lactam.
Zeolite encapsulated active metal composites and their photocatalytic studies for rhodamine-B, reactive red-198 and chloro-phenols
Authors: Reddy G. Ramanjaneya , Balasubramanian S. , Chennakesavulu K.
Published: September 2015

Niobium (Nb), tantalum (Ta) and palladium (Pd) were impregnated in the cavities of a zeolite by the ion exchange method.
pH-dependent and self-healing properties of mussel modified poly(vinyl alcohol) hydrogels in a metal-free environment
Authors: Shi Dongjian , Liu Rongjin , Dong Weifu , Li Xiaojie , Zhang Hongji , Chen Mingqing , Akashi Mitsuru
Published: September 2015

We describe a simple strategy towards a DOPA-based PVA hydrogel with pH-dependent and rapid self-healing properties in the absence of metal ions. The hydrogel could self-heal in 270 s which was much quicker than that prepared in the presence of Fe3+.
Needle-like MnO2/activated carbon nanocomposites derived from human hair as versatile electrode materials for supercapacitors
Authors: Deng Dian , Kim Byoung-Suhk , Gopiraman Mayakrishnan , Kim Ick Soo
Published: September 2015

Efficient needle-like MnO2/activated carbon nanocomposites have been prepared and demonstrated as versatile electrode materials for supercapacitors.
Fluorous bispidine: a bifunctional reagent for copper-catalyzed oxidation and knoevenagel condensation reactions in water
Authors: Ang Wei Jie , Chng Yong Sheng , Lam Yulin
Published: September 2015

Fluorous bispidine-type ligands have been developed to demonstrate its bifunctional property as a ligand and base in copper-catalyzed aerobic oxidation, the Knoevenagel condensation and tandem oxidation/condensation in water under mild conditions.
Anatase TiO2 nanoparticles with controllable crystallinity as a substrate for SERS: improved charge-transfer contribution
Authors: Gong Mengdi , Jiang Xin , Du Juan , Li Xiuling , Han Xiaoxia , Yang Libin , Zhao Bing
Published: September 2015

Anatase TiO2 nanoparticles were controllably synthesized by a very simple sol-hydrothermal method with the assistance of H2SO4 for improving their SERS performances.
Scanning fluorescence correlation spectroscopy as a versatile tool to measure static and dynamic properties of soft matter systems
Authors: Nepal Manish , Oyler-Yaniv Alon , Krichevsky Oleg
Published: September 2015

Scanning fluorescence correlation spectroscopy in combination with specific fluorescence labeling is used to measure different static and dynamic properties of a soft matter system.
Spectroscopic and nonlinear optical properties of the four positional isomers of 4α-(4-tert-butylphenoxy)phthalocyanine
Authors: Ngubeni Grace N. , Britton Jonathan , Mack John , New Edward , Hancox Ian , Walker Marc , Nyokong Tebello , Jones Tim S. , Khene Samson
Published: September 2015

An enhanced NLO response in terms of both the β and γ values was observed for C4h isomer compared to the other isomers, smallest NLO response were observed for the C2v and Cs isomers, respectively.
Nrf2 in health and disease: current and future clinical implications
Authors: Al-Sawaf Othman , Clarner Tim , Fragoulis Athanassios , Kan Yuet Wai , Pufe Thomas , Streetz Konrad , Wruck Christoph Jan
Published: September 2015

The transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) is a major regulator of oxidative stress defence in the human body. As Nrf2 regulates the expression of a large battery of cytoprotective genes, it plays a crucial role in the prevention of degenerative disease in multiple organs. Thus it has been the focus of research as a pharmacological target that could be used for prevention and treatment of chronic diseases such as multiple sclerosis, chronic kidney disease or cardiovascular diseases. The present review summarizes promising findings from basic research and shows which Nrf2-targeting therapies are currently being investigated in clinical trials and which agents have already entered clinical practice.
Control of non‐linear switched systems with average dwell time: interval observer‐based framework
Authors: He Zhongwei , Xie Wei
Published: September 2015

The authors address control system design based on an interval observer for non‐linear switched systems with non‐linear vector functions that are assumed to satisfy Lipschitz conditions. First, the observer gain satisfying a Metzler matrix can be solved by optimisations of linear matrix inequalities (LMIs). Second, an interval observer is designed to estimate the states of non‐linear switched systems with the average dwell time scheme, and sufficient conditions for state estimation are presented in terms of an LMI formulation. Third, based on an interval observer, state feedback matrices are designed to construct an asymptotically stabilising switching controller. Finally, a numerical example is provided to demonstrate the efficiency of the approach.
Robust and fast beamforming with magnitude response constraints for multiple‐input multiple‐output radar
Authors: Yu HongBo , Feng DaZheng , Nie WeiKe
Published: September 2015

In this study, a new robust and fast beamformer is developed for multiple‐input multiple‐output radar to improve the robustness against steering vector (SV) mismatches. A convex robust model with magnitude response constraints (MRC) is established by using the conjugate symmetry characteristic of the transmitted–received SV. To reduce the computational complexity and the number of samples required, the full‐dimensional weight vector (WV) is expressed as the Kronecker product of the transmitted and received array WVs. Thus, the convex problem is converted into a bi‐quadratic cost function and it is solved by combining the bi‐iterative algorithm and convex quadratic program. The proposed beamformer can flexibly control the beamwidth of the robust region and achieve high output signal‐to‐interference‐plus‐noise ratio. Moreover, the proposed method has lower computational complexity and faster sample convergence rate as compared with the traditional MRC‐iterative second‐order cone programming and MRC‐semi‐definite programming beamformers. Finally, numerical simulations are provided to demonstrate the effectiveness and robustness of the proposed beamformer.
Computational discovery of lanthanide doped and Co-doped Y3Al5O12 for optoelectronic applications
Authors: Choudhary Kamal , Chernatynskiy Aleksandr , Mathew Kiran , Bucholz Eric W. , Phillpot Simon R. , Sinnott Susan B. , Hennig Richard G.
Published: September 2015

We systematically elucidate the optoelectronic properties of rare-earth doped and Ce co-doped yttrium aluminum garnet (YAG) using hybrid exchange-correlation functional based density functional theory. The predicted optical transitions agree with the experimental observations for single doped Ce:YAG, Pr:YAG, and co-doped Er,Ce:YAG. We find that co-doping of Ce-doped YAG with any lanthanide except Eu and Lu lowers the transition energies; we attribute this behavior to the lanthanide-induced change in bonding environment of the dopant atoms. Furthermore, we find infrared transitions only in case of the Er, Tb, and Tm co-doped Ce:YAG and suggest Tm,Ce:YAG and Tb,Ce:YAG as possible functional materials for efficient spectral up-conversion devices.
Power combination of a self-coherent high power microwave source
Authors: Yan Xiaolu , Zhang Xiaoping , Li Yangmei , Dang Fangchao , Zhang Jun
Published: September 2015

In our previous work, generating two phase-locked high power microwaves (HPMs) in a single self-coherent HPM device has been demonstrated. In this paper, after optimizing the structure of the previous self-coherent source, we design a power combiner with a folded phase-adjustment waveguide to realize power combination between its two sub-sources. Further particle-in-cell simulation of the combined source shows that when the diode voltage is 687 kV and the axial magnetic field is 0.8 T, a combined output microwave with 3.59 GW and 9.72 GHz is generated. The impedance of the combined device is 36 Ω and the total power conversion efficiency is 28%.
Combined temperature and density series for fluid-phase properties. I. Square-well spheres
Authors: Elliott J. Richard , Schultz Andrew J. , Kofke David A.
Published: September 2015

Cluster integrals are evaluated for the coefficients of the combined temperature- and density-expansion of pressure: Z = 1 + B2(β) η + B3(β) η2 + B4(β) η3 + ⋯, where Z is the compressibility factor, η is the packing fraction, and the Bi(β) coefficients are expanded as a power series in reciprocal temperature, β, about β = 0. The methodology is demonstrated for square-well spheres with λ = [1.2-2.0], where λ is the well diameter relative to the hard core. For this model, the Bi coefficients can be expressed in closed form as a function of β, and we develop appropriate expressions for i = 2-6; these expressions facilitate derivation of the coefficients of the β series. Expanding the Bi coefficients in β provides a correspondence between the power series in density (typically called the virial series) and the power series in β (typically called thermodynamic perturbation theory, TPT). The coefficients of the β series result in expressions for the Helmholtz energy that can be compared to recent computations of TPT coefficients to fourth order in β. These comparisons show good agreement at first order in β, suggesting that the virial series converges for this term. Discrepancies for higher-order terms suggest that convergence of the density series depends on the order in β. With selection of an appropriate approximant, the treatment of Helmholtz energy that is second order in β appears to be stable and convergent at least to the critical density, but higher-order coefficients are needed to determine how far this behavior extends into the liquid.
Electronic structure origin of conductivity and oxygen reduction activity changes in low-level Cr-substituted (La,Sr)MnO3
Authors: Tsekouras George , Boudoire Florent , Pal Banabir , Vondráček Martin , Prince Kevin C. , Sarma D. D. , Braun Artur
Published: September 2015

The electronic structure of the (La0.8Sr0.2)0.98Mn1−xCrxO3 model series (x = 0, 0.05, or 0.1) was measured using soft X-ray synchrotron radiation at room and elevated temperature. O K-edge near-edge X-ray absorption fine structure (NEXAFS) spectra showed that low-level chromium substitution of (La,Sr)MnO3 resulted in lowered hybridisation between O 2p orbitals and M 3d and M 4sp valance orbitals. Mn L3-edge resonant photoemission spectroscopy measurements indicated lowered Mn 3d–O 2p hybridisation with chromium substitution. Deconvolution of O K-edge NEXAFS spectra took into account the effects of exchange and crystal field splitting and included a novel approach whereby the pre-peak region was described using the nominally filled t2g↑ state. 10% chromium substitution resulted in a 0.17 eV lowering in the energy of the t2g↑ state, which appears to provide an explanation for the 0.15 eV rise in activation energy for the oxygen reduction reaction, while decreased overlap between hybrid O 2p–Mn 3d states was in qualitative agreement with lowered electronic conductivity. An orbital-level understanding of the thermodynamically predicted solid oxide fuel cell cathode poisoning mechanism involving low-level chromium substitution on the B-site of (La,Sr)MnO3 is presented.
Site-specific dissociation dynamics of H2/D2 on Ag(111) and Co(0001) and the validity of the site-averaging model
Authors: Hu Xixi , Jiang Bin , Xie Daiqian , Guo Hua
Published: September 2015

Dissociative chemisorption of polyatomic molecules on metal surfaces involves high-dimensional dynamics, of which quantum mechanical treatments are computationally challenging. A promising reduced-dimensional approach approximates the full-dimensional dynamics by a weighted average of fixed-site results. To examine the performance of this site-averaging model, we investigate two distinct reactions, namely, hydrogen dissociation on Co(0001) and Ag(111), using accurate first principles potential energy surfaces (PESs). The former has a very low barrier of ∼0.05 eV while the latter is highly activated with a barrier of ∼1.15 eV. These two systems allow the investigation of not only site-specific dynamical behaviors but also the validity of the site-averaging model. It is found that the reactivity is not only controlled by the barrier height but also by the topography of the PES. Moreover, the agreement between the site-averaged and full-dimensional results is much better on Ag(111), though quantitative in neither system. Further quasi-classical trajectory calculations showed that the deviations can be attributed to dynamical steering effects, which are present in both reactions at all energies.
Point contact tunneling spectroscopy apparatus for large scale mapping of surface superconducting properties
Authors: Groll Nickolas , Pellin Michael J. , Zasadzinksi John F. , Proslier Thomas
Published: September 2015

We describe the design and testing of a point contact tunneling spectroscopy device that can measure material surface superconducting properties (i.e., the superconducting gap Δ and the critical temperature TC) and density of states over large surface areas with size up to mm2. The tip lateral (X,Y) motion, mounted on a (X,Y,Z) piezo-stage, was calibrated on a patterned substrate consisting of Nb lines sputtered on a gold film using both normal (Al) and superconducting (PbSn) tips at 1.5 K. The tip vertical (Z) motion control enables some adjustment of the tip-sample junction resistance that can be measured over 7 orders of magnitudes from a quasi-ohmic regime (few hundred Ω) to the tunnel regime (from tens of kΩ up to few GΩ). The low noise electronic and LabVIEW program interface are also presented. The point contact regime and the large-scale motion capabilities are of particular interest for mapping and testing the superconducting properties of macroscopic scale superconductor-based devices.
Autodetachment spectroscopy of the aluminum oxide anion dipole bound state
Authors: Mascaritolo Kyle J. , Gardner Adrian M. , Heaven Michael C.
Published: September 2015

The 1Σ+←X1Σ+ ground state to dipole bound state (DBS) electronic transition of AlO− has been studied by means of autodetachment spectroscopy. Vibrational and rotational molecular constants for AlO− have been determined for both the ground state (υ″ = 0, 1) and the excited DBS (υ′ = 0, 1). These data provide an improved determination of the electron affinity for AlO (2.6110(7) eV) that is consistent with an earlier measurement. The electron binding energy of the DBS was found to be 52 ± 6 cm−1. Experimental results are compared with the predictions from high level ab initio calculations.
Dynamic range tuning of graphene nanoresonators
Authors: Parmar Marsha M. , Gangavarapu P. R. Yasasvi , Naik A. K.
Published: September 2015

From sensing perspective, smaller electromechanical devices, in general, are expected to be more responsive to the stimuli. This enhanced performance, however, is contingent upon the noise sources remaining unchanged and the onset of nonlinear behavior not being precipitated by miniaturization. In this paper, we study the effect of strain on the nonlinearities and dynamic range in graphene nanoresonators. The dynamic response and the onset of nonlinearity in these devices are sensitive both to the electrostatic field used to actuate the device and the strain. By tuning the strain of the device by two orders of magnitude, we observe an enhancement of 25 dB in the dynamic range leading to a mass resolution of 100 yoctogram. The increase in dynamic range in our devices is modeled as a combined effect of strain and partial cancellation of elastic and electrostatic nonlinearities.
Nanowire dopant measurement using secondary ion mass spectrometry
Authors: Chia A. C. E. , Dhindsa N. , Boulanger J. P. , Wood B. A. , Saini S. S. , LaPierre R. R.
Published: September 2015

A method is presented to improve the quantitative determination of dopant concentration in semiconductor nanowire (NW) arrays using secondary ion mass spectrometry (SIMS). SIMS measurements were used to determine Be dopant concentrations in a Be-doped GaAs thin film and NW arrays of various pitches that were dry-etched from the same film. A comparison of these measurements revealed a factor of 3 to 12 difference, depending on the NW array pitch, between the secondary Be ion yields of the film and the NW arrays, despite being identically doped. This was due to matrix effects and ion beam mixing of Be from the NWs into the surrounding benzocyclobutene that was used to fill the space between the NWs. This indicates the need for etched NWs to be used as doping standards instead of 2D films when evaluating NWs of unknown doping by SIMS. Using the etched NWs as doping standards, NW arrays of various pitches grown by the vapour-liquid-solid mechanism were characterized by SIMS to yield valuable insights into doping mechanisms.
Influence of Ce doping on structural and photoelectric properties of CuInS2 thin films
Authors: Zhu Jun , Xiao Lingling , Ding Tiezhu , Wang Yanlai , Fan Yue
Published: September 2015

Cerium doped CuInS2 thin films were successfully fabricated by a powder metallurgy method. X-ray diffraction and scanning electron microscope measurements showed that the as-prepared CuIn1−xCexS2 samples are of good crystallinity and crystallize with chalcopyrite structure when sintering at 550 °C. The presence of Ce3+ in host material was conformed by X-ray photoelectron spectroscopy. Two subband photon absorption peaks were observed at 1710 nm (0.73 eV) and 1955 nm (0.63 eV) in the UV–Vis–NIR absorption spectrum. This behavior could suggest that an intermediate band forms in the forbidden band of CuInS2 semiconductor due to cerium incorporation. The optical bandgap of CuIn1−xCexS2 films was tuned in the range of 1.38 eV to 1.23 eV with increasing cerium content. And the electrical conductivity could be improved if doped moderate cerium content, especially x = 0.1.
Hydrogen bond network in the hydration layer of the water confined in nanotubes increasing the dielectric constant parallel along the nanotube axis
Authors: Qi Wenpeng , Zhao Hongwei
Published: September 2015

The water confined in nanotubes has been extensively studied, because of the potential usages in drug delivery and desalination. The radial distribution of the dielectric constant parallel along the nanotube axis was obtained by molecular dynamics simulations in a carbon nanotube and a nanotube with a very small van der Waals potential. The confined water was divided into two parts, the middle part water and the hydration water. In both cases, the hydrogen bond orientation of the middle water is isotropic, while the hydrogen bonds in hydration layers are apt to parallel along the nanotube axis. Therefore, the hydration water has higher dipole correlations increasing the dielectric constant along the nanotube axis.
Observation of silicon self-diffusion enhanced by the strain originated from end-of-range defects using isotope multilayers
Authors: Isoda Taiga , Uematsu Masashi , Itoh Kohei M.
Published: September 2015

Si self-diffusion in the presence of end-of-range (EOR) defects is investigated using natSi/28Si isotope multilayers. The isotope multilayers were amorphized by Ge ion implantation, and then annealed at 800–950 °C. The behavior of Si self-interstitials is investigated through the 30Si self-diffusion. The experimental 30Si profiles show further enhancement of Si self-diffusion at the EOR defect region, in addition to the transient enhanced diffusion via excess Si self-interstitials by EOR defects. To explain this additional enhanced diffusion, we propose a model which takes into account enhanced diffusion by tensile strain originated from EOR defects. The calculation results based on this model have well reproduced the experimental 30Si profiles.
Reduced graphene oxide mid-infrared photodetector at 300 K
Authors: Fernandes Gustavo E. , Kim Jin Ho , Oller Declan , Xu Jimmy
Published: September 2015

We report on uncooled mid-infrared photovoltaic responses at 300 K arising in heterojunctions of reduced graphene oxide with p-Si. Two major photoresponse spectral peaks are observed, one in the near infrared starting at 1.1 μm corresponding to electron-hole pair generation in the Si substrate, and another at wavelengths below 2.5 μm, arising from properties of the reduced graphene oxide-Si heterojunction. Our analysis of the current-voltage characteristics at various temperatures suggests that the two materials form a type-II (broken-gap) heterojunction, with a characteristic transition between direct tunneling to field emission, to over-the-barrier excitation with increasing reverse voltage. Illumination was found to affect the onset of the transition between direct tunneling and field-emission, suggesting that the mid infrared response results from the excitation of minority carriers (electrons) from the Si and their collection in the reduced graphene oxide contact. The photoresponse near 1.1 μm showed a time constant at least five times faster than the one at 2.5 μm, which points to surface defects as well as high series resistance and capacitance as potentially limiting factors in this mode of operation. With proper device engineering considerations, these devices could be promising as a graphene-based platform for infrared sensing.
Synthesis of phylogeny and taxonomy into a comprehensive tree of life
Authors: Hinchliff Cody E. , Smith Stephen A. , Allman James F. , Burleigh J. Gordon , Chaudhary Ruchi , Coghill Lyndon M. , Crandall Keith A. , Deng Jiabin , Drew Bryan T. , Gazis Romina , Gude Karl , Hibbett David S. , Katz Laura A. , Laughinghouse H. Dail , McTavish Emily Jane , Midford Peter E. , Owen Christopher L. , Ree Richard H. , Rees Jonathan A. , Soltis Douglas E. , Williams Tiffani , Cranston Karen A.
Published: September 2015

Significance

Scientists have used gene sequences and morphological data to construct tens of thousands of evolutionary trees that describe the evolutionary history of animals, plants, and microbes. This study is the first, to our knowledge, to apply an efficient and automated process for assembling published trees into a complete tree of life. This tree and the underlying data are available to browse and download from the Internet, facilitating subsequent analyses that require evolutionary trees. The tree can be easily updated with newly published data. Our analysis of coverage not only reveals gaps in sampling and naming biodiversity but also further demonstrates that most published phylogenies are not available in digital formats that can be summarized into a tree of life.
Light-enhanced bioaccumulation of molybdenum by nitrogen-deprived recombinant anoxygenic photosynthetic bacterium Rhodopseudomonas palustris
Authors: Naito Taki , Sachuronggui  , Ueki Masayoshi , Maeda Isamu
Published: September 2015

As molybdenum (Mo) is an indispensable metal for plant nitrogen metabolisms, accumulation of dissolved Mo into bacterial cells may connect to the development of bacterial fertilizers that promote plant growth. In order to enhance Mo bioaccumulation, nitrogen removal and light illumination were examined in anoxygenic photosynthetic bacteria (APB) because APB possess Mo nitrogenase whose synthesis is strictly regulated by ammonium ion concentration. In addition, an APB, Rhodopseudomonas palustris, transformed with a gene encoding Mo-responsive transcriptional regulator ModE was constructed. Mo content was most markedly enhanced by the removal of ammonium ion from medium and light illumination while their effects on other metal contents were limited. Increases in contents of trace metals including Mo by the genetic modification were observed. Thus, these results demonstrated an effective way to enrich Mo in the bacterial cells by the culture conditions and genetic modification.
Impact of Antibiotic Choice on Pneumonia Readmission Rates
Authors: Hemenway Alice N. , Naretta Michael A.
Published: September 2015

There are many patient and institutional variables associated with a higher risk of rehospitalization within 30 days of an admission for community-acquired pneumonia. However, less is known regarding the impact of antibiotics. A retrospective cohort study of 271 patients was performed to determine whether, when controlling for known factors for readmission, the choice of antibiotic affects 30-day rehospitalization after an index admission of pneumonia. Multivariate logistic regression analysis was performed to determine correlation between antibiotic choice and readmission rates. Empiric tobramycin was associated with a 31.2% increased risk of readmission for any reason (P < 0.01). Empiric and treatment aztreonam were associated with a 13.7% and 13.5% increased risk of readmission with recurrent pneumonia, respectively (both P < 0.05). Further research evaluating these associations is warranted.
Structure and evolutionary history of a large family of NLR proteins in the zebrafish
Authors: Howe Kerstin , Schiffer Philipp H. , Zielinski Julia , Wiehe Thomas , Laird Gavin K. , Marioni John C. , Soylemez Onuralp , Kondrashov Fyodor , Leptin Maria
Published: September 2015

Animals and plants have evolved a range of mechanisms for recognizing noxious substances and organisms. A particular challenge, most successfully met by the adaptive immune system in vertebrates, is the specific recognition of potential pathogens, which themselves evolve to escape recognition. A variety of genomic and evolutionary mechanisms shape large families of proteins dedicated to detecting pathogens and create the diversity of binding sites needed for epitope recognition. One family involved in innate immunity are the NACHT-domain-and Leucine-Rich-Repeat-containing (NLR) proteins. Mammals have a small number of NLR proteins, which are involved in first-line immune defense and recognize several conserved molecular patterns. However, there is no evidence that they cover a wider spectrum of differential pathogenic epitopes. In other species, mostly those without adaptive immune systems, NLRs have expanded into very large families. A family of nearly 400 NLR proteins is encoded in the zebrafish genome. They are subdivided into four groups defined by their NACHT and effector domains, with a characteristic overall structure that arose in fishes from a fusion of the NLR domains with a domain used for immune recognition, the B30.2 domain. The majority of the genes are located on one chromosome arm, interspersed with other large multi-gene families, including a new family encoding proteins with multiple tandem arrays of Zinc fingers. This chromosome arm may be a hot spot for evolutionary change in the zebrafish genome. NLR genes not on this chromosome tend to be located near chromosomal ends.

Extensive duplication, loss of genes and domains, exon shuffling and gene conversion acting differentially on the NACHT and B30.2 domains have shaped the family. Its four groups, which are conserved across the fishes, are homogenised within each group by gene conversion, while the B30.2 domain is subject to gene conversion across the groups. Evidence of positive selection on diversifying mutations in the B30.2 domain, probably driven by pathogen interactions, indicates that this domain rather than the LRRs acts as a recognition domain. The NLR-B30.2 proteins represent a new family with diversity in the specific recognition module that is present in fishes in spite of the parallel existence of an adaptive immune system.
A cost analysis of a cancer genetic service model in the UK
Authors: Slade Ingrid , Hanson Helen , George Angela , Kohut Kelly , Strydom Ann , Wordsworth Sarah , Rahman Nazneen ,   MCG Programme
Published: September 2015

Background

Technological advances in DNA sequencing have made gene testing fast and more affordable. Evidence of cost-effectiveness of genetic service models is essential for successful translation, but remain sparse in the literature. In particular there is a lack of cost data related to genetic services.

Methods

A detailed micro-costing of 28 pathways relating to breast and/or ovarian cancer and gene testing for theBRCA1andBRCA2genes (termed ‘BRCA testing’) was carried out. These data were combined with patient-level data from a Royal Marsden Cancer Genetics Service audit during which BRCA testing was offered to individuals at ≥10% risk of having a mutation.

Results

The average cost across all pathways was £2,222.68 (range £376.47-£13,531.24). The average pathway cost for a person with cancer was £1897.71 compared to £2,403.22 for a person without cancer. Of the women seen during audit period, 38% were affected with breast and/or ovarian cancer and 62% were unaffected but concerned about their family history.

Conclusion

There is considerable variation in the costs of different gene testing pathways. Improved cost-efficiency could be achieved by increasing the proportion of cancer patients tested, because the pathway cost of an unaffected individual in whom testing has already been performed in a relative with cancer is considerably less.

Acknowledgements

We acknowledge NHS funding to the Royal Marsden/ICR NIHR Specialist Biomedical Research Centre for Cancer. SW is supported by funding through the NIHR Oxford Biomedical Research Centre. This work was supported by Wellcome Trust Award 098518/Z/12/Z. For MCG programme seewww.mcgprogramme.com.

Conflict of Interest Statement

There are no conflicts of interests for any author of this paper
Understanding consumer loyalty to technology-based self-services with credence qualities
Authors: Schuster Lisa , Proudfoot Judy , Drennan Judy
Published: September 2015

Purpose

– This paper aims to use the Model of Goal-Directed Behavior (MGB) to examine the factors affecting consumers’ continued use of emerging technology-based self-services (TBSSs) with credence qualities. Professional services, which traditionally require specialized knowledge and high levels of interpersonal interaction to produce owing to their credence qualities, are increasingly delivered via self-service technologies. Health services delivered via mobile devices, for example, facilitate self-care without direct involvement from health professionals.

Design/methodology/approach

– A mental health service delivered via the Internet and mobile phone, myCompass, was selected as the research context. Twenty interviews were conducted with users of myCompass and the data were thematically analyzed.

Findings

– The findings of the study showcase the unique determinants of consumers’ continued use of TBSSs with credence qualities relative to the more routine services which have been the focus of extant research. The findings further provide support for the utility of the MGB in explaining service continuance, although the importance of distinguishing between extrinsic and intrinsic motivational components of behavioral desire and capturing the impact of social influence beyond subjective norms is also highlighted.

Originality/value

– This study contributes to recent research examining differences in consumer responses across TBSSs and behavioral loyalty to these services. It also provides empirical evidence for broadening and deepening the MGB within this behavioral domain.