bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological encoding in German children's language production: evidence from event-related brain potentials
Authors: JESSEN ANNA , FLEISCHHAUER ELISABETH , CLAHSEN HARALD
Published: March 2016

This study reports developmental changes in morphological encoding across late childhood. We examined event-related brain potentials (ERPs) during the silent production of regularly vs. irregularly inflected verb forms (viz. -tvs. -nparticiples of German) in groups of eight- to ten-year-olds, eleven- to thirteen-year-olds, and adults. The adult data revealed an enhanced (right-frontal) negativity 300–450 ms after cue onset for the (silent) production of -trelative to -npast participle forms (e.g.geplantvs.gehauen‘planned’ vs. ‘hit’). For the eleven- to thirteen-year-olds, the same enhanced negativity was found, with a more posterior distribution and a longer duration (=300–550 ms). The eight- to ten-year-olds also showed this negativity, again with a posterior distribution, but with a considerably delayed onset (800–1,000 ms). We suggest that this negativity reflects combinatorial processing required for producing -tparticiples in both children and adults and that the spatial and temporal modulations of this ERP effect across the three participant groups are due to developmental changes of the brain networks involved in processing morphologically complex words.
Development of a Decision Support System in Ship-To-Ship Lightering
Authors: Husjord Dagfinn
Published: March 2016

This paper focusses on the development of a tool for decision-making, tailored for personnel involved in complex Ship-To-Ship (STS) operations, to enhance the efficiency and safety of these operations. A step-wise approach has been selected. The first step includes specification, development and testing of the tool in a simulated work environment using full-mission simulators. In the second step the findings from application of the tool in the simulated work environment will be used to develop a prototype which will be tested during real life STS operations. This paper describes work done in the first of these two steps. During four iterations, a Graphical User Interface (GUI) has been made following Interaction Design (IxD) principles. The designs have been iteratively developed and tested by experienced ship's officers in a ship-handling simulator to clarify key information to enhance their Situation Awareness (SA) and decision-making process. In order to find indicators for performance, an initial performance test was carried out in a ship-handling simulator. The test indicates that a logic based Decision-Support System (DSS) can improve existing simulator-based training activities in STS operations.
The Custody Crucible: The Development of Scientific Authority About Gay and Lesbian Parents
Authors: George Marie-Amélie
Published: March 2016

In 1974, gay father Bruce Voeller sought visitation with his three children after divorcing his wife. The New Jersey family court held a six day trial that centered on expert witness testimony as to whether Voeller's homosexuality would be detrimental to his children. Drs. Richard Green and John Money testified on Voeller's behalf, whereas Voeller's ex-wife called Dr. Richard Gardner, who concluded that “‘the total environment to which the father exposed the children could impede healthy sexual development in the future.’” In his opinion, which imposed strict limitations on visitation, the judge focused on the opposition within the American Psychiatric Association (APA) over the decision to declassify homosexuality as a mental illness, reasoning that psychiatrists' inability to agree on how to define or classify homosexuality indicated that it was impossible to know what effect Voeller's homosexuality would have on his children. The court consequently concluded that the medical controversy, combined with “the immutable effects which are engendered by the parent-child relationship, demands that the court be most hesitant in allowing any unnecessary exposure of a child to an environment which may be deleterious.” The court imposed visitation restrictions to prevent the children from being in “any homosexual related activities,” which included prohibiting Voeller from ever introducing his partner to the children.
Gene expression, oocyte nuclear maturation and developmental competence of bovine oocytes and embryos produced after in vivo and in vitro heat shock
Authors: Pavani Krishna C. , Baron Erica , Correia Pedro , Lourenço Joana , Bettencourt Bruno Filipe , Sousa Madalena , da Silva Fernando Moreira
Published: March 2016

Three assays were performed. In assay 1, oocytes harvested during the winter months were subjected to kinetic heat shock by stressing the oocytes at 39.5°C (HS1) or at 40.5°C (HS2) for either 6, 12, 18 or 24 h and then matured at control temperature (38.5°C). The nuclear maturation rates (NMR) of all oocytes were recorded after 24 h. In assay 2, oocytes collected year-round maturated, were implanted via in vitro fertilization (IVF) and developed for 9 days. Gene expression analysis was performed on target genes (Cx43, CDH1, DNMT1, HSPA14) with reference to the two housekeeping genes (GAPDH and SDHA) in embryos. Similarly, in assay 3, genetic analysis was performed on the embryos produced from heat-stressed oocytes (from HS1 and HS2). In assay 1, the duration of heat stress resulted in a significant decline in NMR (P < 0.05) with HS1 for maturated oocytes at 86.4 ± 4.3; 65.5 ± 0.7; 51.3 ± 0.9; 38.1 ± 1.9 and 36.3 ± 0.9, for control, 6 h, 12 h, 18 h and 24 h, respectively. For assays 2 and 3, results demonstrated that DNMT1, Cx43 and HSPA14 were down-regulated in the embryos produced in the warm with respect to the cold months (P < 0.05). A constant up- and down-regulation of DNMT1 and HSPA14 genes were observed in both HS-treated samples. Also, an inconsistent pattern of gene expression was observed in Cx43 and CDH1 genes (P < 0.05). Targeted gene expression was aberrant in embryo development, which can provide evidence on early embryo arrest and slowed embryo development.
Medical Support for Aircraft Disaster Search and Recovery Operations at Sea: the RSN Experience
Authors: Teo Kok Ann Colin , Chong Tse Feng Gabriel , Liow Min Han Lincoln , Tang Kong Choong
Published: March 2016

The maritime environment presents a unique set of challenges to search and recovery (SAR) operations. There is a paucity of information available to guide provision of medical support for SAR operations for aircraft disasters at sea. The Republic of Singapore Navy (RSN) took part in two such SAR operations in 2014 which showcased the value of a military organization in these operations. Key considerations in medical support for similar operations include the resultant casualty profile and challenges specific to the maritime environment, such as large distances of area of operations from land, variable sea states, and space limitations. Medical support planning can be approached using well-established disaster management life cycle phases of preparedness, mitigation, response, and recovery, which all are described in detail. This includes key areas of dedicated training and exercises, force protection, availability of air assets and chamber support, psychological care, and the forensic handling of human remains. Relevant lessons learned by RSN from the Air Asia QZ8501 search operation are also included in the description of these key areas.

TeoKAC, ChongTFG, LiowMHL, TangKC. Medical support for aircraft disaster search and recovery operations at sea: the RSN experience. Prehosp Disaster Med. 2016; 31(3):294–299.
The UCLA study of Predictors of Cognitive Functioning Following Moderate/Severe Pediatric Traumatic Brain Injury
Authors: Moran Lisa M. , Babikian Talin , Del Piero Larissa , Ellis Monica U. , Kernan Claudia L. , Newman Nina , Giza Christopher C. , Mink Richard , Johnson Jeffrey , Babbitt Christopher , Asarnow Robert
Published: March 2016

Objectives:Following pediatric moderate-to-severe traumatic brain injury (msTBI), few predictors have been identified that can reliably identify which individuals are at risk for long-term cognitive difficulties. This study sought to determine the relative contribution of detailed descriptors of injury severity as well as demographic and psychosocial factors to long-term cognitive outcomes after pediatric msTBI.Methods:Participants included 8- to 19-year-olds, 46 with msTBI and 53 uninjured healthy controls (HC). Assessments were conducted in the post-acute and chronic stages of recovery. Medical record review provided details regarding acute injury severity. Parents also completed a measure of premorbid functioning and behavioral problems. The outcome of interest was four neurocognitive measures sensitive to msTBI combined to create an index of cognitive performance.Results:Results indicated that none of the detailed descriptors of acute injury severity predicted cognitive performance. Only the occurrence of injury, parental education, and premorbid academic competence predicted post-acute cognitive functioning. Long-term cognitive outcomes were best predicted by post-acute cognitive functioning.Discussion:The findings suggest that premorbid factors influence cognitive outcomes nearly as much as the occurrence of a msTBI. Furthermore, of youth with msTBI who initially recover to a level of moderate disability or better, a brief cognitive battery administered within several months after injury can best predict which individuals will experience poor long-term cognitive outcomes and require additional services. (JINS, 2016,22, 1–8)
Executive Impairment Is Associated with Impaired Memory Performance in Working-Aged Stroke Patients
Authors: Turunen Katri E.A. , Laari Siiri P.K. , Kauranen Tatu V. , Mustanoja Satu , Tatlisumak Turgut , Poutiainen Erja
Published: March 2016

Objectives:Executive dysfunction is associated with impaired memory performance, but controversies remain about which aspects of memory are involved and how general intelligence influences these connections. We aimed to clarify these connections in stroke patients by comparing various memory measures in patients with and without executive impairment.Methods:Our consecutive cohort included patients with a first-ever ischemic stroke. Neuropsychological assessments were completed 6 months and 2 years after stroke. We classified patients as executively impaired, when at least two of five executive measures were defective at 6 months. At both 6 months and 2 years, we compared list learning of unrelated words, story recall, and recall of geometric figures in patients with and without executive impairment, while controlling for general intelligence.Results:Patients with executive impairment (n=66; 37%) performed worse in list learning (p=.001; partial η2=.058) and immediate recall of a logical passage (p=.010; partial η2=.037) 6 months after stroke compared to executively intact patients (n=113). At the end of the 2-year follow-up period, the patients who were executively impaired at 6 months (n=53; 37%) still performed worse than executively intact patients (n=92) in list learning (p<.001; partial η2=.096), and additionally in delayed recall of the list (p=.006; partial η2=.052) and immediate recall of geometric figures (p=.007; partial η2=.050).Conclusions:In our working-aged stroke patients, executive impairment was common. Executive impairment was associated with memory tasks that provided less inherent structure and required the use of active memory strategies. Clinicians should remember this role of executive dysfunction when interpreting memory performance. (JINS, 2016,22, 1–10)
Common ways Americans are incorporating fruits and vegetables into their diet: intake patterns by meal, source and form, National Health and Nutrition Examination Survey 2007–2010
Authors: Moore Latetia V , Hamner Heather C , Kim Sonia A , Dalenius Karen
Published: March 2016

Objective

We explored how Americans aged ≥2 years who consumed the recommended amount of fruits and vegetables on a given day incorporated fruits and vegetables into their diet compared with those who did not consume recommended amounts.

Design

We used 1 d of dietary recall data from the National Health and Nutrition Examination Survey (NHANES) 2007–2010 to examine cross-sectional differences in mean intakes of fruits and vegetables in cup-equivalents by meal, source and form between the two groups.

Setting

USA.

Subjects

NHANES 2007–2010 participants aged ≥2 years (n 17 571) with 1 d of reliable 24 h recall data.

Results

On a given day, the proportions of fruits and vegetables consumed at different meals were similar between those who consumed recommended amounts and those who did not. Among adults, 59–64 % of their intake of fruits was consumed at breakfast or as a snack and almost 90 % came from retail outlets regardless of whether they consumed the recommended amount or not. Adults who consumed the recommended amount of fruits ate more fruits in raw form and with no additions than those who did not. Among children and adults, 52–57 % of vegetables were consumed at dinner by both groups. Retail outlets were the main source of vegetables consumed (60–68 %).

Conclusions

Our findings indicate that habits of when, where and how consumers eat fruits and vegetables might not need to change but increasing the amount consumed would help those not currently meeting the recommendation.
THE FORMATION OF LARGE-AMPLITUDE FINGERS IN ATMOSPHERIC VORTICES
Authors: COSGROVE JASON M. , FORBES LAWRENCE K.
Published: March 2016

Large-scale low-pressure systems in the atmosphere are occasionally observed to possess Kelvin–Helmholtz fingers, and an example is shown in this paper. However, these structures are hundreds of kilometres long, so that they are necessarily affected strongly by nonlinearity. They are evidently unstable and are observed to dissipate after a few days.

A model for this phenomenon is presented here, based on the usual $f$-plane equations of meteorology, assuming an atmosphere governed by the ideal gas law. Large-amplitude perturbations are accounted for, by retaining the equations in their nonlinear forms, and these are then solved numerically using a spectral method. Finger formation is modelled as an initial perturbation to the $n$th Fourier mode, and the numerical results show that the fingers grow in time, developing structures that depend on the particular mode. Results are presented and discussed, and are also compared with the predictions of the ${\it\beta}$-plane theory, in which changes of the Coriolis acceleration with latitude are included. An idealized vortex in the northern hemisphere is considered, but the results are at least in qualitative agreement with an observation of such systems in the southern hemisphere.
‘ON DIFFERENTIAL CHARACTERISTIC CLASSES’
Authors: HO MAN-HO
Published: March 2016

In this erratum we correct a mistake in Ho [‘On differential characteristic classes’, J. Aust. Math. Soc.99(1) (2015), 30–47].
THE ILLIMITABLE RIGHT: DEBATING THE MEANING OF PROPERTY AND THEMARCHÉ À TERMEIN NAPOLEONIC FRANCE
Authors: LEUCHTER TYSON
Published: March 2016

At a critical moment during the Napoleonic era, the stockbrokers of Paris were summoned before the Council of State to defend themarché à terme, or futures contract in public debt. Surprisingly, despite official disdain and ample legal opportunity for prohibition, the brokers’ argument was successful, and themarché à termeescaped repression. The defense of themarché à termeturned on the nature of property. To critics, it divided property from possession, severing property from any concrete anchors. Advocates, by contrast, pointed to the inherent abstraction of property encoded in legal norms. These debates helped shape a concept of property in which economic utility, legal validity, and moral grounding converged. As a central pillar of the new regime, this concept of property also constrained political authority. The successful defense of themarché à termeshows that property was a right that not even authoritarian regimes could restrict arbitrarily.
Dealing with farmers’ Ethnolinguistic differences when collecting crop diversity on-farm
Authors: Kamau Joseph Ireri , Labeyrie Vanesse , Njoroge Grace Njeri , Wanjoya Anthony Kibira , Wambugu Peterson Weru , Muthamia Zachary Kithinji , Leclerc Christian
Published: March 2016

Identification and characterization of the farmers’ named crop varieties cultivated around the world is a major issue for conservation and sustainable use of plant genetic resources. Intraspecific diversity is strongly determined by farmers’ socio-cultural environment, but this has little been documented. In this paper, we tested, on a contact zone among three ethnolinguistic groups located on the Mount Kenya region, whether farmers’ socio-cultural differences have an impact on the morphological characteristics of the farmers’ named sorghum varieties. Eighteen qualitative morphological traits of the panicles were measured. We first compared the morphological diversity of the named varieties among ethnolinguistic groups using multivariate analysis of homogeneity of groups’ dispersion and tested their differentiation using permutational multivariate analysis of variance. Discriminant analysis of principal components was then used to categorize the morphological diversity withouta priori, and this classification was compared with farmers’ local taxonomy (vernacular names) in the three ethnolinguistic groups. Our results show that some morphotypes are peculiar to some ethnolinguistic groups and that a morphotype can bear different variety names while the same variety name can be used to identify different morphotypes. Morphological differentiation that was explained by ethnolinguistic groups was higher for local landraces than for improved varieties. Our findings imply that socio-cultural diversity of farmers and the criteria they use to identify and maintain landraces need to be considered in studying and sampling crop diversity forin situas well as forex situconservation.
Role of genetic resources and molecular markers inMucuna pruriens(L.) DC improvement
Authors: Sathyanarayana N. , Mahesh S. , Leelambika M. , Jaheer M. , Chopra R. , Rashmi K. V.
Published: March 2016

Mucuna pruriens(L.) DC is a tropical legume cover crop with promising nutritional and agronomic potentials. It is also a key source of 3,4 dihydroxy-L-phenylalanine (L-Dopa) – a precursor of dopamine used in the treatment of Parkinson's disease. However, lack of well-characterized germplasm plus poor accessibility to genomic resources has hindered its breeding programs. Furthermore, the cause and effect of various biotic and abiotic stresses impacting yield is also little studied. Systematic collection and evaluation of Indian germplasm by our group revealed presence of a diverse gene pool in India that can support a variety of breeding needs. The stability of L-Dopa trait across environments examined through Genotype and environment (G × E) interaction studies, as well as feasibility check on barcoding and phylogenetic analyses based on karyotype and conserved nuclear and chloroplast genes showed promising outcome. Germplasm screening for select biotic abiotic stresses identified resilient genotypes. Advances in use of DNA markers for diversity analysis, linkage map development, tagging of genes/quantitative trait loci for qualitative and quantitative traits, and progress in genomics are presented.
Magnetoelectric coupling and spin-induced electrical polarization in metal–organic magnetic chains
Authors: Scarrozza Marco , Barone Paolo , Sessoli Roberta , Picozzi Silvia
Published: March 2016

We report first-principles predictions of magnetoelectric coupling in organic magnetic helices and clarify the microscopic mechanism of spin-induced electric polarization.
Accelerated synthesis of Sn-BEA in fluoride media: effect of H2O content in the gel
Authors: Yakimov Alexander V. , Kolyagin Yury G. , Tolborg Søren , Vennestrøm Peter N. R. , Ivanova Irina I.
Published: March 2016

Sn-BEA synthesis in concentrated gels results in 2.5–4 fold reduction of crystallization time and formation of smaller zeolite crystals.
Block copolymers based on 2-methyl- and 2-phenyl-oxazoline by metallocene-mediated cationic ring-opening polymerization: synthesis and characterization
Authors: Kourti Maria-Evgenia , Fega Eirini , Pitsikalis Marinos
Published: March 2016

The cationic polymerization of oxazolines, lactones and vinyl ethers can be efficiently promoted by metallocene complexes activated by floroaryl borates.
Pd-catalyzed aminocarbonylation of alkynes with amines using Co2(CO)8 as a carbonyl source
Authors: Dong Yaxi , Sun Suyan , Yang Fan , Zhu Yu , Zhu Weiguo , Qiao Huijie , Wu Yusheng , Wu Yangjie
Published: March 2016

A facile protocol for aminocarbonylation of alkynes with amines at room temperature was developed using a metal carbonyl source.
Comparative study of preparation, characterization and anticandidal activities of a chitosan silver nanocomposite (CAgNC) compared with low molecular weight chitosan (LMW-chitosan)
Authors: Dananjaya S. H. S. , Kulatunga D. C. M. , Godahewa G. I. , Lee Jehee , De Zoysa Mahanama
Published: March 2016

A chitosan-silver nanocomposite (CAgNC) was synthesized in a green manner using low molecular weight chitosan (LMW-chitosan) and silver nitrate without applying external chemical reducing agents.
Growth of vertically aligned MoS2 nanosheets on a Ti substrate through a self-supported bonding interface for high-performance lithium-ion batteries: a general approach
Authors: Zhou Yu , Liu Yong , Zhao Wenxia , Xie Fangyan , Xu Ruimei , Li Baojun , Zhou Xiang , Shen Hui
Published: March 2016

Interconnected MoS2 nanosheets were grown on Ti foil via a self-supported TiO2 bonding interface to preferentially expose the active edge sites.
Thienylphenothiazine integrated pyrenes: an account on the influence of substitution patterns on their optical and electroluminescence properties
Authors: Konidena Rajendra Kumar , Justin Thomas K. R. , Singh Meenu , Jou Jwo-Huei
Published: March 2016

A new set of thienylphenothiazine-integrated pyrenes have been prepared by Stille coupling reactions in good yields and characterized by optical, electrochemical, thermal and electroluminescence investigations.
Unusual Case of Sinusitis Related to Ectopic Teeth in the Maxillary Sinus Roof/Orbital Floor: A Report
Authors: Chagas Júnior OtacílioLuiz , Moura LucasBorin , Sonego CamilaLeal , de Farias Eduardo Oliveira Campos , Giongo CarolineComis , Fonseca Alisson André Robe
Published: March 2016

This article presents a case report of an adult patient with chronic sinusitis related to the presence of two erupted ectopic teeth located atypically in the maxillary sinus roof/orbital floor after a long latency period associated with childhood facial trauma. This article aims to show the treatment of chronic sinusitis of odontogenic origin by surgical removal of ectopic teeth in an unusual position by direct visualization. This case report discusses the signs and symptoms of chronic sinusitis linked to the presence of ectopic elements and associated with an inflammatory cyst, the choice of complementary tests for diagnosis and surgical treatment through the Caldwell-Luc procedure. After a 2-year follow-up period, the patient presently shows clinical improvement, thus demonstrating the success of the chosen treatment.
Long-Term Results of Orbital Roof Repair with Titanium Mesh in a Case of Traumatic Intraorbital Encephalocele: A Case Report and Review of Literature
Authors: Arslan Erhan , Arslan Selçuk , Kalkısım Selçuk , Arslan Ahmet , Kuzeyli Kayhan
Published: March 2016

Orbital roof fractures associated with cranial and maxillofacial trauma are rarely encountered. Traumatic intraorbital encephaloceles due to orbital roof fractures developing in the early posttraumatic period are even rarer. A variety of materials, such as alloplastic implants or autogenous materials, have been used for the reconstruction of orbital roof, but data regarding the long-term results of these materials are very limited. We report a case of intraorbital encephalocele developing in the early posttraumatic period (2 days) in a child patient and the long-term results of titanium mesh used for the reconstruction of the orbital roof. The case is presented with a pertinent review of literature.
The 3-point Virasoro algebra and its action on a Fock space
Authors: Cox Ben , Jurisich Elizabeth , Martins Renato A.
Published: March 2016

We define the 3-point Virasoro algebra and construct a representation of it on a previously defined Fock space for the 3-point affine algebra.
High yield, single crystal ice via the Bridgman method
Authors: Bisson Patrick , Groenzin Henning , Barnett Irene Li , Shultz Mary Jane
Published: March 2016

The surface chemistry of ice and of water is an important topic of study, especially given the role of ice and water in shaping the environment. Although snow, granular, and polycrystalline ice are often used in research, there are applications where large surface areas of a known crystallographic plane are required. For example, fundamental spectroscopy or scattering studies rely on large area samples of known crystalline orientation. In addition, due to its slower dynamics and decreased number of molecular configurations, ice can be viewed as a reduced complexity model for the complex hydrogen bonding environment found at the surface and within the bulk of liquid water. In our studies using Sum Frequency Generation (SFG) vibrational spectroscopy, we have shown that each crystalline face has a unique spectral signature and therefore a unique chemistry and chemical activity. A reliable, reproducible, high performance method of producing large single crystal samples is needed to support this surface chemistry research. The design, construction, and use of a computer-controlled, ice-growth machine based on the Stockbarger modified Bridgeman technique is described. The instrument reliably produces relatively large single crystals that are optically flawless (that is, no visible flaws when viewed in a crossed polarizer), and in very high yield. Success rates of 95% are typical. Such performance has not been observed in the literature.
Lagrangian velocity and acceleration correlations of large inertial particles in a closed turbulent flow
Authors: Machicoane Nathanaël , Volk Romain
Published: March 2016

We investigate the response of large inertial particle to turbulent fluctuations in an inhomogeneous and anisotropic flow. We conduct a Lagrangian study using particles both heavier and lighter than the surrounding fluid, and whose diameters are comparable to the flow integral scale. Both velocity and acceleration correlation functions are analyzed to compute the Lagrangian integral time and the acceleration time scale of such particles. The knowledge of how size and density affect these time scales is crucial in understanding particle dynamics and may permit stochastic process modelization using two-time models (for instance, Sawford’s). As particles are tracked over long times in the quasi-totality of a closed flow, the mean flow influences their behaviour and also biases the velocity time statistics, in particular the velocity correlation functions. By using a method that allows for the computation of turbulent velocity trajectories, we can obtain unbiased Lagrangian integral time. This is particularly useful in accessing the scale separation for such particles and to comparing it to the case of fluid particles in a similar configuration.
Asynchronous τ-leaping
Authors: Jȩdrzejewski-Szmek Zbigniew , Blackwell Kim T.
Published: March 2016

Stochastic simulation of cell signaling pathways and genetic regulatory networks has contributed to the understanding of cell function; however, investigation of larger, more complicated systems requires computationally efficient algorithms. τ-leaping methods, which improve efficiency when some molecules have high copy numbers, either use a fixed leap size, which does not adapt to changing state, or recalculate leap size at a heavy computational cost. We present a hybrid simulation method for reaction-diffusion systems which combines exact stochastic simulation and τ-leaping in a dynamic way. Putative times of events are stored in a priority queue, which reduces the cost of each step of the simulation. For every reaction and diffusion channel at each step of the simulation the more efficient of an exact stochastic event or a τ-leap is chosen. This new approach removes the inherent trade-off between speed and accuracy in stiff systems which was present in all τ-leaping methods by allowing each reaction channel to proceed at its own pace. Both directions of reversible reactions and diffusion are combined in a single event, allowing bigger leaps to be taken. This improves efficiency for systems near equilibrium where forward and backward events are approximately equally frequent. Comparison with existing algorithms and behaviour for five test cases of varying complexity shows that the new method is almost as accurate as exact stochastic simulation, scales well for large systems, and for various problems can be significantly faster than τ-leaping.
Structural, dynamical, and transport properties of the hydrated halides: How do At− bulk properties compare with those of the other halides, from F− to I−?
Authors: Réal Florent , Severo Pereira Gomes André , Guerrero Martínez Yansel Omar , Ayed Tahra , Galland Nicolas , Masella Michel , Vallet Valérie
Published: March 2016

The properties of halides from the lightest, fluoride (F−), to the heaviest, astatide (At−), have been studied in water using a polarizable force-field approach based on molecular dynamics (MD) simulations at the 10 ns scale. The selected force-field explicitly treats the cooperativity within the halide-water hydrogen bond networks. The force-field parameters have been adjusted to ab initio data on anion/water clusters computed at the relativistic Möller-Plesset second-order perturbation theory level of theory. The anion static polarizabilities of the two heaviest halides, I− and At−, were computed in the gas phase using large and diffuse atomic basis sets, and taking into account both electron correlation and spin-orbit coupling within a four-component framework. Our MD simulation results show the solvation properties of I− and At− in aqueous phase to be very close. For instance, their first hydration shells are structured and encompass 9.2 and 9.1 water molecules at about 3.70 ± 0.05 Å, respectively. These values have to be compared to the F−, Cl−, and Br− ones, i.e., 6.3, 8.4, and 9.0 water molecules at 2.74, 3.38, and 3.55 Å, respectively. Moreover our computations predict the solvation free energy of At− in liquid water at ambient conditions to be 68 kcal mol−1, a value also close the I− one, about 70 kcal mol−1. In all, our simulation results for I− are in excellent agreement with the latest neutron- and X-ray diffraction studies. Those for the At− ion are predictive, as no theoretical or experimental data are available to date.
Stochastic Schrödinger evolution over piecewise enlarged filtrations
Authors: Mengütürk Levent Ali
Published: March 2016

This paper constructs a nonlinear filtering framework that admits appearances of new information processes at random times by introducing piecewise enlargements of filtrations and proposes a new energy-based Schrodinger evolution expressed as a stochastic differential equation on a complex Hilbert space. Each information process is modeled as the sum of a random variable taking the eigenvalues of a Hamiltonian and an independent Brownian bridge noise. It is shown that under a piecewise enlarged filtration, the wave function is a jump-diffusion process until it collapses at some terminal time. In between discontinuities, the dynamics of the state vector are governed by different Wiener processes and diffusion coefficients. This motivates the introduction of an inclusive chain of Kolmogorov probability spaces or a *-isomorphic chain of commutative von Neumann probability spaces, on which the quantum system evolves differently based on the number of active information processes. The expectation of the Hamiltonian at a given state is the solution of a second-order nonlinear differential equation determined by one of the possible regimes that the quantum system belongs to. It is shown that the collapse rate is a submartingale with positive jumps and the Shannon entropy process is a supermartingale with expected negative jumps when passing to higher-order probability spaces. The framework is extended to the case when the Hamiltonian is modeled as a function of a set of commutative operators, where each operator is associated with a different piecewise enlarged filtration.
Solution of the complete Curtiss-Bird model for polymeric liquids subjected to simple shear flow
Authors: Stephanou Pavlos S. , Kröger Martin
Published: March 2016

The complete kinetic theory model for concentrated polymer solutions and melts proposed by Curtiss and Bird is solved for shear flow: (a) analytically by providing a solution for the single-link (or configurational) distribution function as a real basis spherical harmonics expansion and then calculating the materials functions in shear flow up to second order in the dimensionless shear rate and, (b) numerically via the execution of Brownian dynamics simulations. These two methods are actually complementary to each other as the former is accurate only for small dimensionless shear rates where the latter produces results with increasingly large uncertainties. The analytical expansions of the material functions with respect to the dimensionless shear rate reduce to those of the extensively studied, simplified Curtiss-Bird model when ε′ = 0, and to the rigid rod when ε′ = 1. It is known that the power-law behavior at high shear rates is very different for these two extremal cases. We employ Brownian dynamics simulation to not only recover the limiting cases but to find a gradual variation of the power-law behaviors at large dimensionless shear rates upon varying ε′. The fact that experimental data are usually located between these two extremes strongly advocates the significance of studying the solution of the Curtiss-Bird model. This is exemplified in this work by comparing the solution of this model with available rheological data for semiflexible biological systems that are clearly not captured by the original Doi-Edwards or simplified Curtiss-Bird models.
Statistical effects related to low numbers of reacting molecules analyzed for a reversible association reaction A + B = C in ideally dispersed systems: An apparent violation of the law of mass action
Authors: Szymanski R. , Sosnowski S. , Maślanka Ł.
Published: March 2016

Theoretical analysis and computer simulations (Monte Carlo and numerical integration of differential equations) show that the statistical effect of a small number of reacting molecules depends on a way the molecules are distributed among the small volume nano-reactors (droplets in this study). A simple reversible association A + B = C was chosen as a model reaction, enabling to observe both thermodynamic (apparent equilibrium constant) and kinetic effects of a small number of reactant molecules. When substrates are distributed uniformly among droplets, all containing the same equal number of substrate molecules, the apparent equilibrium constant of the association is higher than the chemical one (observed in a macroscopic—large volume system). The average rate of the association, being initially independent of the numbers of molecules, becomes (at higher conversions) higher than that in a macroscopic system: the lower the number of substrate molecules in a droplet, the higher is the rate. This results in the correspondingly higher apparent equilibrium constant. A quite opposite behavior is observed when reactant molecules are distributed randomly among droplets: the apparent association rate and equilibrium constants are lower than those observed in large volume systems, being the lower, the lower is the average number of reacting molecules in a droplet. The random distribution of reactant molecules corresponds to ideal (equal sizes of droplets) dispersing of a reaction mixture. Our simulations have shown that when the equilibrated large volume system is dispersed, the resulting droplet system is already at equilibrium and no changes of proportions of droplets differing in reactant compositions can be observed upon prolongation of the reaction time.
Thermoelectric properties of semiconductor nanowire networks
Authors: Roslyak Oleksiy , Piryatinski Andrei
Published: March 2016

To examine the thermoelectric (TE) properties of a semiconductor nanowire (NW) network, we propose a theoretical approach mapping the TE network on a two-port network. In contrast to a conventional single-port (i.e., resistor) network model, our model allows for large scale calculations showing convergence of TE figure of merit, ZT, with an increasing number of junctions. Using this model, numerical simulations are performed for the Bi2Te3 branched nanowire (BNW) and Cayley tree NW (CTNW) network. We find that the phonon scattering at the network junctions plays a dominant role in enhancing the network ZT. Specifically, disordered BNW and CTNW demonstrate an order of magnitude higher ZT enhancement compared to their ordered counterparts. Formation of preferential TE pathways in CTNW makes the network effectively behave as its BNW counterpart. We provide formalism for simulating large scale nanowire networks hinged upon experimentally measurable TE parameters of a single T-junction.
A multi-pathway model for photosynthetic reaction center
Authors: Qin M. , Shen H. Z. , Yi X. X.
Published: March 2016

Charge separation occurs in a pair of tightly coupled chlorophylls at the heart of photosynthetic reaction centers of both plants and bacteria. Recently it has been shown that quantum coherence can, in principle, enhance the efficiency of a solar cell, working like a quantum heat engine. Here, we propose a biological quantum heat engine (BQHE) motivated by Photosystem II reaction center (PSII RC) to describe the charge separation. Our model mainly considers two charge-separation pathways which is more than that typically considered in the published literature. We explore how these cross-couplings increase the current and power of the charge separation and discuss the effects of multiple pathways in terms of current and power. The robustness of the BQHE against the charge recombination in natural PSII RC and dephasing induced by environments is also explored, and extension from two pathways to multiple pathways is made. These results suggest that noise-induced quantum coherence helps to suppress the influence of acceptor-to-donor charge recombination, and besides, nature-mimicking architectures with engineered multiple pathways for charge separations might be better for artificial solar energy devices considering the influence of environments.
CMOS-compatible method for doping of buried vertical polysilicon structures by solid phase diffusion
Authors: Turkulets Yury , Silber Amir , Ripp Alexander , Sokolovsky Mark , Shalish Ilan
Published: March 2016

Polysilicon receives attention nowadays as a means to incorporate 3D-structured photonic devices into silicon processes. However, doping of buried layers of a typical 3D structure has been a challenge. We present a method for doping of buried polysilicon layers by solid phase diffusion. Using an underlying silicon oxide layer as a dopant source facilitates diffusion of dopants into the bottom side of the polysilicon layer. The polysilicon is grown on top of the oxide layer, after the latter has been doped by ion implantation. Post-growth heat treatment drives in the dopant from the oxide into the polysilicon. To model the process, we studied the diffusion of the two most common silicon dopants, boron (B) and phosphorus (P), using secondary ion mass spectroscopy profiles. Our results show that shallow concentration profiles can be achieved in a buried polysilicon layer using the proposed technique. We present a quantitative 3D model for the diffusion of B and P in polysilicon, which turns the proposed method into an engineerable technique.
Effect of cleaning procedures on the electrical properties of carbon nanotube transistors—A statistical study
Authors: Tittmann-Otto J. , Hermann S. , Kalbacova J. , Hartmann M. , Toader M. , Rodriguez R. D. , Schulz S. E. , Zahn D. R. T. , Gessner T.
Published: March 2016

The interface between a carbon nanotube (CNT) and its environment can dramatically affect the electrical properties of CNT-based field-effect transistors (FETs). For such devices, the channel environment plays a significant role inducing doping or charge traps giving rise to hysteresis in the transistor characteristics. Thereby the fabrication process strongly determines the extent of those effects and the final device performance. In CNT-based devices obtained from dispersions, a proper individualization of the nanotubes is mandatory. This is generally realized by an ultrasonic treatment combined with surfactant molecules, which enwrap nanotubes forming micelle aggregates. To minimize impact on device performance, it is of vital importance to consider post-deposition treatments for removal of surfactant molecules and other impurities. In this context, we investigated the effect of several wet chemical cleaning and thermal post treatments on the electrical characteristics as well as physical properties of more than 600 devices fabricated only by wafer-level compatible technologies. We observed that nitric acid and water treatments improved the maximum-current of devices. Additionally, we found that the ethanol treatment successfully lowered hysteresis in the transfer characteristics. The effect of the chemical cleaning procedures was found to be more significant on CNT-metal contacts than for the FET channels. Moreover, we investigated the effect of an additional thermal cleaning step under vacuum after the chemical cleaning, which had an exceptional impact on the hysteresis behavior including hysteresis reversal. The presence of surfactant molecules on CNT was evidenced by X-ray photoelectron and Raman spectroscopies. By identifying the role of surfactant molecules and assessing the enhancement of device performance as a direct consequence of several cleaning procedures, these results are important for the development of CNT-based electronics at the wafer-level.
Structural and relaxor-like dielectric properties of unfilled tungsten bronzes Ba5−5xSm5xTi5xNb10−5xO30
Authors: Wei T. , Dong Z. , Zhao C. Z. , Guo Y. Y. , Zhou Q. J. , Li Z. P.
Published: March 2016

New unfilled tetragonal tungsten bronze (TTB) oxides, Ba5−5xSm5xTi5xNb10−5xO30 (BSTN-x), where 0.10 ≤ x ≤ 0.35, have been synthesized in this work. Their crystal structure was determined and analyzed based on Rietveld structural refinement. It is found that single TTB phase can be formed in a particular x range (i.e., 0.15 ≤ x ≤ 0.3) due to the competition interaction between tolerance factor and electronegativity difference. Furthermore, dielectric and ferroelectric results indicate that phase transitions and ferroelectric states are sensitive to x. Referring to the local chemistry, we suggest that the raise of vacancies at the A2-site compared with that of A1-site will intensely depress the normal ferroelectric phase and is in favor of relaxor ferroelectric state. Macroscopically, previous A-site size difference standpoint on fill TTB compounds cannot give a reasonable explanation about the variation of dielectric maximum temperature (Tm) for present BSTN-x compounds. Alternatively, tetragonality (c/a) is adopted which can well describe the variation of Tm in whole x range. In addition, one by one correspondence between tetragonality and electrical features can be found, and the compositions involving high c/a are usually stabilized in normal ferroelectric phase. It is believed that c/a is a more appropriate parameter to illustrate the variation of ferroelectric properties for unfilled TTB system.
Observation of a scrolled graphene nanoribbons with gap-plasmonic system
Authors: Jung Myunghee , Moon Jin-San , Park Won-Hwa
Published: March 2016

We report an observation of a scrolled graphene nanoribbon (sGNR) produced via a chemical vapor deposition. The sandwiched sGNR between Au nanoparticle and Au thin film system can be identified by the remarkable enhancement of G peak accompanied with a subsequent splitting (G+ and G−) with strong Radial Breading Like Mode enhancement. Because the weak adhesion force between graphene monolayer and target Au substrate during transfer maybe result in a sparse distribution of sGNR with a z-directional curvature-induced G peak splitting. Reproducibility and mass production with a nanometer scale circuit devices may be anticipated from this work.
Controlling the state of polarization via optical nanoantenna feeding with surface plasmon polaritons
Authors: Xie Yu-Bo , Liu Zheng-Yang , Wang Qian-Jin , Sun Guang-Hou , Zhang Xue-Jin , Zhu Yong-Yuan
Published: March 2016

Optical nanoantennas, usually referring to metal structures with localized surface plasmon resonance, could efficiently convert confined optical energy to free-space light, and vice versa. But it is difficult to manipulate the confined visible light energy for its nanoscale spatial extent. Here, a simple method is proposed to solve this problem by controlling surface plasmon polaritons to indirectly manipulate the localized plasmons. As a proof of principle, we demonstrate an optical rotation device which is a grating with central circular polarization optical nanoantenna. It realized the arbitrary optical rotation of linear polarized light by controlling the retard of dual surface plasmon polaritons sources from both side grating structures. Furthermore, we use a two-parameter theoretical model to explain the experimental results.
Ellipsometric investigation of ZnFe2O4 thin films in relation to magnetic properties
Authors: Zviagin V. , Kumar Y. , Lorite I. , Esquinazi P. , Grundmann M. , Schmidt-Grund R.
Published: March 2016

We report an influence of disorder on structural and magnetic properties of ZnFe2O4 thin films grown at temperatures ranging from 400 °C to 600 °C by pulsed laser deposition in O2 atmosphere on SrTiO3 (100) substrates evidenced by properties of electronic transitions observed in the dielectric function. Inversion of the normal spinel structure was found to be one of the main mechanisms responsible for the increase in the magnetic response for the lowest growth temperature. The enhanced feature in the dielectric function located at ∼3.5 eV, related to the transition involving tetrahedrally coordinated Fe3+ cations, corresponds to the dominating magnetic coupling between the octahedral and tetrahedral lattice sites, responsible for the overall ferrimagnetic behaviour of the film grown at the lowest temperature.