bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of Kilonovae from Dynamical and Post-merger Ejecta of Neutron Star Mergers
Authors: Tanaka Masaomi , Kato Daiji , Gaigalas Gediminas , Rynkun Pavel , Radžiūtė Laima , Wanajo Shinya , Sekiguchi Yuichiro , Nakamura Nobuyuki , Tanuma Hajime , Murakami Izumi , Sakaue Hiroyuki A.
Published: January 2018

Ejected material from neutron star mergers gives rise to electromagnetic emission powered by radioactive decays of r-process nuclei, the so-called kilonova or macronova. While properties of the emission are largely affected by opacities in the ejected material, available atomic data for r-process elements are still limited. We perform atomic structure calculations for r-process elements: Se (Z = 34), Ru (Z = 44), Te (Z = 52), Ba (Z = 56), Nd (Z = 60), and Er (Z = 68). We confirm that the opacities from bound–bound transitions of open f-shell, lanthanide elements (Nd and Er) are higher than those of the other elements over a wide wavelength range. The opacities of open s-shell (Ba), p-shell (Se and Te), and d-shell (Ru) elements are lower than those of open f-shell elements, and their transitions are concentrated in the ultraviolet and optical wavelengths. We show that the optical brightness can be different by

mag depending on the element abundances in the ejecta such that post-merger, lanthanide-free ejecta produce brighter and bluer optical emission. Such blue emission from post-merger ejecta can be observed from the polar directions if the mass of the preceding dynamical ejecta in these regions is small. For the ejecta mass of 0.01

, observed magnitudes of the blue emission will reach 21.0 mag (100 Mpc) and 22.5 mag (200 Mpc) in the g and r bands within a few days after the merger, which are detectable with 1 m or 2 m class telescopes.
Low-energy Spectra of Gamma-Ray Bursts from Cooling Electrons
Authors: Geng Jin-Jun , Huang Yong-Feng , Wu Xue-Feng , Zhang Bing , Zong Hong-Shi
Published: January 2018

The low-energy spectra of gamma-ray bursts’ (GRBs) prompt emission are closely related to the energy distribution of electrons, which is further regulated by their cooling processes. We develop a numerical code to calculate the evolution of the electron distribution with given initial parameters, in which three cooling processes (i.e., adiabatic, synchrotron, and inverse Compton cooling) and the effect of a decaying magnetic field are coherently considered. A sequence of results is presented by exploring the plausible parameter space for both the fireball and the Poynting flux–dominated regime. Different cooling patterns for the electrons can be identified, and they are featured by a specific dominant cooling mechanism. Our results show that the hardening of the low-energy spectra can be attributed to the dominance of synchrotron self-Compton cooling within the internal shock model or to decaying synchrotron cooling within the Poynting flux–dominated jet scenario. These two mechanisms can be distinguished by observing the hard low-energy spectra of isolated short pulses in some GRBs. The dominance of adiabatic cooling can also lead to hard low-energy spectra when the ejecta is moving at an extreme relativistic speed. The information from the time-resolved low-energy spectra can help to probe the physical characteristics of the GRB ejecta via our numerical results.
Reflection Spectra of the Black Hole Binary Candidate MAXI J1535-571 in the Hard State Observed by NuSTAR
Authors: Xu Yanjun , Harrison Fiona A. , García Javier A. , Fabian Andrew C. , Fürst Felix , Gandhi Poshak , Grefenstette Brian W. , Madsen Kristin K. , Miller Jon M. , Parker Michael L. , Tomsick John A. , Walton Dominic J.
Published: January 2018

We report on a Nuclear Spectroscopic Telescope Array (NuSTAR) observation of the recently discovered bright black hole candidate MAXI J1535-571. NuSTAR observed the source on MJD 58003 (five days after the outburst was reported). The spectrum is characteristic of a black hole binary in the hard state. We observe clear disk reflection features, including a broad Fe Kα line and a Compton hump peaking around 30 keV. Detailed spectral modeling reveals a narrow Fe Kα line complex centered around 6.5 keV on top of the strong relativistically broadened Fe Kα line. The narrow component is consistent with distant reflection from moderately ionized material. The spectral continuum is well described by a combination of cool thermal disk photons and a Comptonized plasma with the electron temperature

keV. An adequate fit can be achieved for the disk reflection features with a self-consistent relativistic reflection model that assumes a lamp-post geometry for the coronal illuminating source. The spectral fitting measures a black hole spin

, inner disk radius

, and a lamp-post height

(statistical errors, 90% confidence), indicating no significant disk truncation and a compact corona. Although the distance and mass of this source are not currently known, this suggests the source was likely in the brighter phases of the hard state during this NuSTAR observation.
Intégration, réseaux sociaux et représentations langagières de migrants en France
Authors: Biichlé Luc
Published: January 2018

Fondé sur un corpus d’environ 300 entretiens dont 150 enregistrés, cet article propose l’étude du réseau social et des représentations de migrants originaires de onze pays différents ainsi que de leurs proches. En effet, la structure du réseau social, par la nature de ses liens, par les contacts qu’elle génère, détermine fortement les représentations et les pratiques, notamment langagières. Pour les migrants, la restructuration du réseau constitue donc une phase importante de l’insertion dans le nouveau pays. L’étude de ces réseaux ainsi que celle des représentations/pratiques des personnes montrent que l’on peut établir des corrélations entre la présence de liens faibles (réseaux ouverts) et les pratiques plurilingues (langue étrangère + français). À l’inverse, un réseau plus dense, moins ouvert, correspondra plutôt à des pratiques monolingues en langue(s) étrangère(s). Les processus intégrationnels, dont l’apprentissage de la langue, semblent donc largement subordonnés à la restructuration du réseau des migrants quelle que soit leur provenance.
Promotions, déclassements et reclassements. À propos du repositionnement symbolique lié aux lapsus politiques
Authors: Descamps David , Foudi Agathe
Published: January 2018

Les lapsus engageant les statuts sociaux des personnalités politiques apparaissent liés à la structure du champ politique. Qu’il s’agisse de promotions, de reclassements ou de déclassements symboliques, la forme prise par ces lapsus semble relever de multiples logiques liées notamment à l’intériorisation de carrières politiques typiques suivies par les personnalités politiques, au prestige inégal associé à tel ou tel statut, à l’intériorisation d’une association entre les acteurs politiques et certains des statuts qu’ils ont pu occuper ou encore à des éléments plus contextuels.
Le pouvoir des algorithmes
Authors: Cardon Dominique
Published: January 2018

Cet article propose un cadre d’interprétation des différentes significations pouvant être données à l’attribution d’un pouvoir aux algorithmes qui, de plus en plus, régissent l’organisation des informations numériques. Il propose d’abord de distinguer certaines caractéristiques du calcul algorithmique en introduisant quelques explications sur leur fonctionnement. La réflexion conduite ici propose ensuite de décomposer différents types d’enjeux portant sur la critique, l’audit et la régulation des algorithmes en tenant compte de la variété des dispositifs dans lesquels ils sont insérés.
L’évolution du niveau de vie des pauvres. La petite paysannerie de la région de Gérone (1750-1800)
Authors: Congost Rosa , Esteve Eulàlia , Serramontmany Albert , Detry Florence
Published: January 2018

Certains débats historiographiques actuels, tels ceux qui concernent les inégalités sociales ou encore plus spécifiquement celui qui entoure la « révolution industrieuse », ont mis en lumière le défi que représente encore, pour l’histoire sociale et l’histoire économique, l’étude de l’évolution du niveau de vie des plus humbles. Cet article entend s’emparer de cette question par une approche régionale, en s’appuyant sur les sources considérées comme les plus significatives. Il apporte un faisceau de preuves pour témoigner d’une amélioration du niveau de vie des individus issus du groupe social des « travailleurs » ( treballadors ) dans la région de Gérone (située au nord-est de la péninsule Ibérique), grâce au croisement des données apportées par deux sources notariales : les contrats de mariage et les inventaires après décès, et par le témoignage direct d’un paysan ampurdanais, Sebastià Casanovas, durant la seconde moitié du XVIII e siècle.
Molecular Dynamics Study of Nonequilibrium [112] Tilt Grain Boundaries in Ni and their Relaxation under Cyclic Deformation
Authors: Nazarov Ayrat A. , Murzaev Ramil’ T.
Published: January 2018

Atomic structure of nonequilibrium [112] tilt grain boundaries in nickel containing disclination dipoles is studied by means of molecular dynamics simulations. Initial systems for simulations are constructed by joining together pieces of two bicrystals one of which contains a symmetric tilt GB S=11 / 62.96° and the other a GB S=105 / 57.12°, or S=125 / 55.39°, or S=31 / 52.20°, so disclination dipoles with strengths w = 5.84°, 7.58° and 10.76° are created. Stress maps plotted after relaxation at zero temperature indicate the presence of high long-range stresses induced by disclination dipoles. Excess energy of GBs due to the nonequilibrium structure is calculated. Effect of oscillating tension-compression stresses on the nonequilibrium GB structure is studied at temperature T = 300 K. The simulations show that the oscillating stress results in a generation of partial lattice dislocations by the GB, their glide across grains and sink at appropriate surfaces that results in a compensation of the disclination stress fields and recovery of an equilibrium GB structure and energy.
The Necessary Duration of a Molecular Dynamics Experiment for the Diffusion Coefficient Calculation
Authors: Poletaev Gennady M. , Medvedeva Ekaterina S. , Novoselova Darya V. , Zorya Irina V. , Starostenkov Mikhail D.
Published: January 2018

The evaluation of the necessary duration of a molecular dynamics experiment for the calculation of the diffusion coefficient at migration of different point defects in Ni (vacancy, bivacancy, self-interstitial atom, hydrogen atom) is held in the present work. It is shown that at the temperature higher than 0.6 of melting point is usually enough the simulation during of 100 ps for this. When calculating of the diffusion coefficient of impurity in the metal crystal, for example, of hydrogen, the decrease of error of mean-square displacements of impurity atoms can be achieved by introducing of a large number of the impurities.
Phase Composition and Defect Substructure of Strengthening Layer Surfaced on Low Alloyed Steel
Authors: Ivanov Yurii F. , Gromov Victor E. , Konovalov Sergey V. , Kormyshev Vassily E. , Qin Rong Shan , Semina Olga A.
Published: January 2018

The microstructure and microhardness distribution in surface of low carbon Hardox 450 steel coated with alloyed powder wires of different chemical compositions are studied. It is shown that the microhardness of 6-8 mm thickness surfaced layer exceeds that of base metal by more than 2 times. The increased mechanical properties of surfaced layer are caused by the submicro and nanoscale dispersed martensite, containing the niobium carbides Nb2C, NbC and iron borides Fe2B. In the bulk plates a dislocation substructure of the net-like type with scalar dislocation density of 1011 cm-2 is observed. The layer surfaced with the wire containing B possesses the highest hardness. The possible mechanisms of niobium and boron carbides formation in surfacing are discussed.
Analysis of the Structure and Thermal Stability of Cu@Si Nanoparticles
Authors: Gafner Yuri Ya. , Gafner Svetlana L. , Nomoev Andrey V. , Bardakhanov Sergey P.
Published: January 2018

In this research core-shell Cu@Si nanoparticles were obtained through evaporation of elemental precursors by a high-powered electron beam. The structures of the particles were investigated in order to elucidate their mechanisms of formation. The thermal stability of the particles was studied with the help of molecular dynamics calculations. The parameters of the thermal stability of the composite nanoparticles Cu@Si with different size were determined. It was concluded that with the temperature increasing the diffusion of copper atoms on the surface begins, leading to a reversal of the structure and the formation of particles having a particle type Si@Cu.
Service oriented product lines - managed service level agreements for better quality of service
Authors: Garusinghe Asanka , Perera Indika , Meedeniya Dulani
Published: January 2018

Service Oriented Architecture (SOA) is being used for developing service oriented applications as a set of business specific web services and gives more flexibility for the software development industry. However, systematic reusability for developing applications to fit customers' individual needs with high customization is significant to increase the productivity and reusability of such service oriented applications. Software Product Line (SPL) has the ability to prepare core sets of assets in an identifiable and reusable manner with manageable variable components. Thus, the combination of SOA and SPL has highlighted the term of Service Oriented Product Line (SOPL), which is used for increasing levels of flexibility and reusability. It helps to develop semantics of variability over identified service components. Likewise, Quality of Service (QoS) attributes play an important role in selection of web services in a SOA environment. Service Level Agreements (SLAs) provide the mechanism with a specification of the verifiable Quality attributes in web services. In this paper, we present our implementation approach of SOPL to manage Service Level Agreements (SLAs) in SOPL environments by monitoring Quality of Service (QoS) attributes in bundles of web service components. The design and development of service bundles for representing core sets of assets in SOPL are followed by the initial feature based analysis and identification of service components. The management of SLAs is handled by detecting the deviation between actual and acceptable predefined QoS metrics values in previously analysed web service components via Web Service Level Agreement (WSLA) language specified templates. The case study based evaluation results indicate the usefulness of research contribution.
Cutting Edge: Plasmodium falciparum Induces Trained Innate Immunity
Authors: Schrum Jacob E. , Crabtree Juliet N. , Dobbs Katherine R. , Kiritsy Michael C. , Reed George W. , Gazzinelli Ricardo T. , Netea Mihai G. , Kazura James W. , Dent Arlene E. , Fitzgerald Katherine A. , Golenbock Douglas T.
Published: January 2018

Malarial infection in naive individuals induces a robust innate immune response. In the recently described model of innate immune memory, an initial stimulus primes the innate immune system to either hyperrespond (termed training) or hyporespond (tolerance) to subsequent immune challenge. Previous work in both mice and humans demonstrated that infection with malaria can both serve as a priming stimulus and promote tolerance to subsequent infection. In this study, we demonstrate that initial stimulation with Plasmodium falciparum–infected RBCs or the malaria crystal hemozoin induced human adherent PBMCs to hyperrespond to subsequent ligation of TLR2. This hyperresponsiveness correlated with increased H3K4me3 at important immunometabolic promoters, and these epigenetic modifications were also seen in Kenyan children naturally infected with malaria. However, the use of epigenetic and metabolic inhibitors indicated that the induction of trained immunity by malaria and its ligands may occur via a previously unrecognized mechanism(s).
IL-10 Deficiency Reveals a Role for TLR2-Dependent Bystander Activation of T Cells in Lyme Arthritis
Authors: Whiteside Sarah K. , Snook Jeremy P. , Ma Ying , Sonderegger F. Lynn , Fisher Colleen , Petersen Charisse , Zachary James F. , Round June L. , Williams Matthew A. , Weis Janis J.
Published: January 2018

T cells predominate the immune responses in the synovial fluid of patients with persistent Lyme arthritis; however, their role in Lyme disease remains poorly defined. Using a murine model of persistent Lyme arthritis, we observed that bystander activation of CD4+ and CD8+ T cells leads to arthritis-promoting IFN-γ, similar to the inflammatory environment seen in the synovial tissue of patients with posttreatment Lyme disease. TCR transgenic mice containing monoclonal specificity toward non–Borrelia epitopes confirmed that bystander T cell activation was responsible for disease development. The microbial pattern recognition receptor TLR2 was upregulated on T cells following infection, implicating it as marker of bystander T cell activation. In fact, T cell–intrinsic expression of TLR2 contributed to IFN-γ production and arthritis, providing a mechanism for microbial-induced bystander T cell activation during infection. The IL-10–deficient mouse reveals a novel TLR2-intrinsic role for T cells in Lyme arthritis, with potentially broad application to immune pathogenesis.
Negative peri-donation events among whole blood donors in a blood bank in Ibadan, Nigeria
Authors: Fasola Foluke A.
Published: January 2018

The existence and sustenance of the blood bank depends on blood donors. It is imperative that the donation experience is satisfactory for the donors. Therefore this study was carried out to determine the frequency of undesirable events experienced by the blood donor as part of donor haemovigilance. This was a retrospective descriptive study of the events that occurred amongst the blood donors of the blood bank of a tertiary institution. The blood donor incident book was reviewed for the period of six months. Negative undesirable events occurred in 2% of the donor populations, of which 45.8% could not complete the blood donation process while only 16.7% completed the blood donation process. Mild vasovagal attack occurred in 0.2% of the donor population. Undisclosed deferrable risk factors/ behaviours were identified by the phlebotomist in the bleeding room which made donors unfit for donation even though they had passed the donor screening criteria. This accounted for 20.8% of those with negative experience. Guidelines are required to identify donors that are not likely to complete donation to avoid wastage of time, blood, resources and reduce undesirable experiences.
Les problèmes posés par le contrôle des vaccins antirabiques administrés par voie orale
Authors: Blancou J.
Published: January 2018

La vaccination par voie orale des animaux sauvages ou domestiques errants contre la rage fait l’objet de recherches et d’applications pratiques extrêmement importantes depuis quelques années. La quantité de vaccin utilisée (plus de 1 million de doses par an en Europe) appelle une harmonisation des contrôles des différents produits proposés : vaccins SAD standard, mutants des virus SAD ou d’autres souches, ex. : vaccins recombinants obtenus par génie génétique. Si le contrôle d’efficacité de tels produits ne pose pas de problème particulier par rapport à celui de vaccins utilisés par voie parentérale, celui du contrôle de leur innocuité se révèle beaucoup plus délicat. En effet les virus-vaccins vivants sont dissimulés dans des appâts distribués sur le terrain. Ils sont donc potentiellement accessibles à des espèces ou individus non cibles, chez lesquels la probabilité d’amorce d’un cycle de réplication virale est encore mal connue. Les modalités actuelles de contrôle de ces vaccins sont exposées et discutées et des règles communes pour les contrôles à venir proposées.
Continuity of Care in Resident Outpatient Clinics: A Scoping Review of the Literature
Authors: Walker Jeremey , Payne Brittany , Clemans-Taylor B. Lee , Snyder Erin Dunn
Published: January 2018

Background 

Continuity between patients and physicians is a core principle of primary care and an accreditation requirement. Resident continuity clinics face challenges in nurturing continuity for their patients and trainees.

Objective 

We undertook a scoping review of the literature to better understand published benchmarks for resident continuity; the effectiveness of interventions to improve continuity; and the impact of continuity on resident and patient satisfaction, patient outcomes, and resident career choice.

Methods 

We developed a MEDLINE search strategy to identify articles that defined continuity in residency programs in internal medicine, family medicine, and pediatrics published prior to December 31, 2015, and used a quality evaluation tool to assess included studies.

Results 

The review includes 34 articles describing 12 different measures of continuity. The usual provider of care and continuity for physician formulas were most commonly utilized, and mean baseline continuity was 56 and 55, respectively (out of a total possible score of 100). Clinic and residency program redesign innovations (eg, advanced access scheduling, team-based care, and block scheduling) were studied and had mixed impact on continuity. Continuity in resident clinics is lower than published continuity rates for independently practicing physicians.

Conclusions 

Interventions to enhance continuity in resident clinics have mixed effects. More research is needed to understand how changes in continuity affect resident and patient satisfaction, patient outcomes, and resident career choice. A major challenge to research in this area is the lack of empanelment of residents' patients, creating difficulties in scheduling and measuring continuity visits.
Library instruction in medical education: a survey of current practices in the United States and Canada
Authors: Nevius Amanda M. , Ettien A’Llyn , Link Alissa P. , Sobel Laura Y.
Published: January 2018

Objective: The most recent survey on instruction practices in libraries affiliated with accredited medical institutions in the United States was conducted in 1996. The present study sought to update these data, while expanding to include Canadian libraries. Additional analysis was undertaken to test for statistically significant differences between library instruction in the United States and Canada and between libraries affiliated with highly ranked and unranked institutions.Methods: A twenty-eight-question survey was distributed to libraries affiliated with accredited US and Canadian medical schools to assess what and how often librarians teach, as well as how librarians are involved in the curriculum committee and if they are satisfied with their contact with students and faculty. Quantitative data were analyzed with SAS, R, and MedCalc.Results: Most of the seventy-three responding libraries provided instruction, both asynchronously and synchronously. Library instruction was most likely to be offered in two years of medical school, with year one seeing the most activity. Database use was the most frequently taught topic, and libraries reported a median of five librarians providing instruction, with larger staffs offering slightly more education sessions per year. Libraries associated with highly ranked schools were slightly more likely to offer sessions that were integrated into the medical school curriculum in year four and to offer sessions in more years overall.Conclusions: In US and Canadian libraries, regardless of the rank of the affiliated medical school, librarians’ provision of instruction in multiple formats on multiple topics is increasingly common. This article has been approved for the Medical Library Association’s Independent Reading Program.
Las raíces isabelinas del teatro por horas y su primer repertorio: en torno a los orígenes del género chico
Authors: Mejías García Enrique
Published: January 2018

Los principales historiadores del denominado “género chico” han insistido en señalar el estrecho vínculo entre la Revolución de 1868 y el nacimiento del teatro por horas en Madrid. Para ellos, la idea de explotar las funciones teatrales por sesiones surgió como respuesta a una pulsión de ocio exigida por el nuevo orden social democrático. Sin embargo, nuestra perspectiva de la cronología y naturaleza de los acontecimientos es diametralmente opuesta, ya que consideramos que el teatro por horas nace como consecuencia de la realidad sociocultural del último periodo de reinado de Isabel II. En este artículo pretendemos profundizar en las raíces isabelinas del teatro por horas ya que, al menos desde 1866, podemos localizar espacios teatrales donde se ofrecían hasta cuatro funciones diarias. El asunto del repertorio de estas salas, el primer género chico, así como su recepción crítica e historiográfica será el otro eje sobre el que centraremos nuestro texto.
Cimentos biocerâmicos em endodontia: revisão de literatura
Authors: Lima Naggila Fernanda Figueiredo , Dos Santos Priscilla Raquel Negreiros , Pedrosa Marlus Da Silva , Delboni Maraisa Greggio
Published: January 2018

Cimentos biocerâmicos vêem se tornando populares na ndodontia como material obturador do sistema de canais radicular devido às suas várias vantagens. Objetivo: Revisar a literatura atualmente disponível sobre as propriedades de cimentos biocerâmicos na endodontia. Metodologia: Uma pesquisa bibliográfica exploratória foi realizada utilizando as bases de dados eletrônicas Public Medline (PubMed), Scopus, Embase, e Web of Science empregando o termo de busca “Bioceramic” AND “Endodontic”. Os critérios de inclusão foram: artigos de pesquisas originais e ensaios clínicos publicados em português, espanhol e inglês. Não foram aplicados limites a data de publicação. Resultados: Foram identificados 30 estudos que abordaram propriedades de cimentos biocerâmicos em endodontia publicados em um período de 7 anos (2011-2017). As propriedades e características vantajosas destacadas nos estudos foram: biocompatibilidade, citotoxicidade, bioatividade, capacidade de manchamento dentário, radiopacidade, pH e extravasamento (extravasamento não se enquadra como propriedade), adaptação marginal, resistência de união, resistência a fratura das raízes, capacidade seladora, e propriedades antibacterianas. Conclusão: Os estudos selecionados para esta revisão de literatura mostram que os cimentos endodônticos biocerâmicos apresentam propriedades promissoras para serem utilizados no tratamento de canais radiculares.
Factores incidentes en el rendimiento académico estudiantil de Ingeniería en Sistemas de Información de la FAREM-Matagalpa, 2012-2016
Authors: Martínez Ramos Guiselle Raquel , Pedroza Pacheco Manuel Enrique
Published: January 2018

El propósito de este estudio es describir factores que inciden en el rendimiento académico de estudiantes de Ing. Sistemas de Información de la FAREM Matagalpa, clasificados como personales, sociales e institucionales. El estudio es mixto, exploratorio y descriptivo, observacional, retrospectivo y transversal. La muestra de estudio fue por conveniencia. Las técnicas de recolección fueron análisis documental y protocolo de encuesta. Se procesaron datos estadísticamente con modelos ANACORR, ANARE, ACP, tablas de contingencia y frecuencia, gráficos de barra, boxplot y pastel para describir resultados. Se concluye que la mayoría de estudiantes desertaron de la carrera en primer año, los estudiantes activos mejoraron levemente el rendimiento cada año, factores personales relevantes fueron competencia cognitiva, motivación, atribuciones causales, bienestar psicológico, asistencia a clases e inteligencia emocional, no existe relación entre promedio de secundaria y de universidad, la última no se asocia con la nota de admisión, factores sociales relevantes fueron entorno familiar, nivel educativo de padres, capital cultural y contexto socioeconómico; factores institucionales determinantes fueron complejidad de estudios, condiciones institucionales, servicios de apoyo, relación estudiante-docente y pruebas de admisión. Se recomienda tomar resultados de esta investigación para profundizar en el tema y mejorar el rendimiento académico de los estudiantes universitarios.
Sugarcane Biochar as an Amendment for Greenhouse Growing Media for the Production of Cucurbit Seedlings
Authors: Webber III Charles L. , White Jr Paul M. , Spaunhorst Douglas J. , Lima Isabel M. , Petrie Eric C.
Published: January 2018

Louisiana sugarcane farmers in 2016 harvested 11.7 million Mg millable sugarcane from 163,000 ha, producing 1.47 million Mg of raw sugar and an estimated 3.5 million Mg of bagasse. Even though Louisiana sugar mills use 80 to 90% of the bagasse for fuel production, another 350,000 to 700,000 Mg of bagasse accumulates each year. The conversion of the excess bagasse into biochar is an excellent option with numerous uses. Research was conducted to determine the impact of sugarcane biochar as an amendment to soilless planting media for the production of cucurbit seedlings. Two biochars were combined by volume with a commercial certified organic soilless growing media into 5 combinations (0%:100%, 25%:75%, 50%:50%, 75%:25%, and 100%:0%, biochars and growing media, respectively). Squash (Cucurbita pepo L.) var. ‘Enterprise’ and cantaloupe (Cucumis melo L.) var. ‘Magnum .45’ were planted in each of the 5 different planting mixtures. The higher heating value (HHV), lower heating value (LHV), and fixed carbon (FixC) were greater for the standard bagasse biochar (SBB), therefore, making it more valuable as a potential fuel source than the pneumatic bagasse biochar (PBB). All of the biochar mixture combinations compared favorably to the commercial media with low bulk densities (0.11 to 0.14 g cm-3) and high water holding capacities (80-87%). In respect to seedling production, the biochars (SBB and PBB) performed well, especially at the 25 and 50% levels for both plant species. The squash seedlings responded better at the 75% level than the cantaloupe seedlings, which reflect differences in nutrient requirements. The 100% biochar growing media are not recommended because both plant species often had a decrease in organic matter. These results indicate that the volume of a standard soilless greenhouse growing media can be successfully extended by adding 25 to 50% sugarcane biochar without a reduction in squash and cantaloupe seedling production. Future research should investigate the impact of additional plant species, as well as different biochar sources on seedling production.
Economics of Weed Management Methods as Influenced by Row-Spacing in Cowpea
Authors: Osipitan O. Adewale , Yahaya I. , Adigun Joseph A.
Published: January 2018

Weed management is an important factor that influences the economic importance of cowpea as a cheap source of food and income for many farmers. A study was conducted to evaluate economic benefits of weed management methods used singly or in an integrated approach, and to understand the influence of row-spacing on economic benefits of weed management methods. Total variable cost of cowpea cultivation was substantially influenced by cost of weed control. A single input of hand weeding resulted in higher cost of weed control than a single input of PRE-herbicide for weed control. Increase in weed control inputs or frequency did not guarantee an increase in economic benefits. For example, removing weeds three times with hand at 3, 6 and 9 weeks after planting (WAP) during the cowpea growing season did not necessarily result in the highest yield, but rather increased the variable cost of weed control. Integrating PRE-herbicide and hand weeding for weed management resulted in the highest yield and gross profit. The lowest cost of weed control provided by using PRE-herbicide gave the highest benefit-cost ratio. The differences in economic values of weed management methods were mostly not affected by cowpea row-spacing, but generally, economic benefits of management methods decreased with increase in row-spacing. Practically, this study suggests that minimizing the use of hand weeding by complementing with PRE-herbicide for weed management could help to optimize yield, and increase profitability, particularly under a narrow row-spacing in cowpea cultivation.
Structural Optimization of Network Arch Bridges with Hollow Tubular Arches and Chords
Authors: Pipinato Alessio
Published: January 2018

In the framework of bridge engineering, cable structure represent a key argument. The development of innovative bridge solutions are needed in order to keep time and costs at a reasonable level, maintaining at the same time an high level of structural safety and functionality. The network arch bridge solution completely respond to these requirements, and in addition could be designed as a very pleasant and formally elegant structure, because of its slenderness and lightness. In this paper, an introduction on the network arch solution is presented, together with structural analysis and data of relevant structures realized. Furthermore, an optimization of specific types of road and railway bridges is presented in the particular case of hollow sections, considering three alternative of cable disposition.
Microstructure and wear resistance of
gas-nitrided steel after laser modification
Authors: Panfil D. , Kulka M. , Wach P. , Michalski J.
Published: January 2018

Purpose: The aim of this work was to study the microstructure and wear resistance of
hybrid surface layers, produced by a controlled gas nitriding and laser modification.
Design/methodology/approach: Nitriding is well-known method of thermo-chemical
treatment, applied in order to produce surface layers of improved hardness and wear
resistance. The phase composition and growth kinetics of the diffusion layer can be
controlled using a gas nitriding with changeable nitriding potential. In this study, gas
nitriding was carried out on 42CrMo4 steel at 570°C (843 K) for 4 hours using changeable
nitriding potential in order to limit the thickness of porous e zone. Next, the nitrided layer
was laser-modified using TRUMPF TLF 2600 Turbo CO2 laser. Laser tracks were arranged
as the multiple tracks with scanning rate vl=2.88 m/min and overlapping of about 86% using
the two laser beam powers (P): 0.21 kW and 0.26 kW. Microstructure was observed by an
optical microscope. Phase composition was studied using XRD. Hardness profiles in the
produced hybrid layers was determined using a Vickers method. Wera resistance tests were
performed using MBT-01 tester.
Findings: Gas nitriding resulted in formation of compound zone, consisting of e nitrides
close to the surface and a zone, composed of e + g' nitrides. Below the white compound
zone, the diffusion zone occurred with nitric sorbite and precipitates of g' nitrides. In the
microstructure after laser heat treatment (LHT) of nitrided layer, the zones were observed
as follows: the re-melted zone (MZ) with e nitrides, nitric martensite and non-equilibrium
FeN0.056 phase, the heat-affected zone (HAZ) with nitric martensite and precipitates of g'
phase and the diffusion zone (DZ) without visible effect of laser treatment. Laser beam power
influenced the depth of MZ and HAZ, so the thickness of hardened zone. The hardness of
MZ was slightly decreased compared to the hardness of compound zone after gas nitriding.
However, the significant increase in hardness was observed in HAZ. The formation of hybrid
layers advantageously influenced the tribological properties. The laser-heat treated nitrided
layers were characterized by improved wear resistance compared to the only gas-nitrided
layer.
Research limitations/implications: The effect of LHT on the microstructure and
properties of gas-nitrided layer was limited to the two laser beam powers. In the future
research, this range should be exceeded, especially, taking into account the lower values of
laser beam power. It will result in laser modification without re-melting.
Practical implications: The selection of suitable LHT parameters could provide the
hybrid layers of modified microstructure and improved wear resistance.
Originality/value: This work was related to the new concept of modification of nitrided
layer by laser heat treatment.
Efecto de las metas de logro y las estructuras de metas de clase 3x2 en la motivación autodeterminada: un análisis multinivel en educación secundaria
Authors: Méndez-Giménez Antonio , Cecchini-Estrada José Antonio , Méndez-Alonso David , Prieto-Saborit José Antonio , Fernández-Río Javier
Published: January 2018

The study faces two objectives: (a) to examine the construct validity of the 3x2 Classroom Goal Structures Questionnaire, and (b) to jointly analyze the influence of the classroom goal structures and 3x2 achievement goals on high school students’ self-determined motivation. 2284 students participated (51.6% men and 48.4% women) aged 12-17 years (M = 14.31 years, SD = 1.15), from 148 classrooms. The results of confirmatory factor analysis supported the hypothesized model. The validity and internal consistency of the questionnaire were satisfactory. The results of hierarchical linear models provided support to the direct, indirect and interaction models. Regarding direct effects, self-approach structure, and self-approach and task-approach goals were positive predictors of self-determined motivation, whereas the other-approach structure, and other-approach and task-avoidance goals were negative predictors. In relation to indirect effects, the results revealed that the three approach goals, and task-avoidance goals were partial mediators of the relationship between the self-approach structure and self-determined motivation, whereas other-approach goals were partial mediators in the relationship with their parallel structure. Regarding the interaction effects, the relationship between task-approach goals and self-determination varied depending on the other-approach structure.
Eficacia ejecutiva en tareas de interferencia tipo Stroop. Estudio de validación de una versión numérica y manual (CANUM)
Authors: Gutiérrez-Martínez Francisco , Ramos-Ortega Melchor , Vila-Chaves José-Óscar
Published: January 2018

This paper presents CANUM, a new numerical and manual version of Stroop interference task. The stimulus used replaces the classical color-word conflict by the numerosity-number conflict considering the interference generated between the symbolic value of the number and the amount of times it is repeated. CANUM also replaces the vocal answer by a simple right-left typing. The aim was twofold: first, to ensure a general measure of attentional control capacity not linked to the verbal factor; and second, to extent the population to whom the test would be applied, avoiding the restrictions on reading ability inherent to the classical Stroop task. The results obtained in a sample of school children reveal a high reliability in terms of internal consistency, as well as a significant predictive validity in relation to two criterial measures: general intelligence and working memory. This supports its usefulness as an instrument for the assessment of executive function and controlled attention applicable in a wide age range, both for research purposes as for clinical and educational goals.
Characteristics of frequent presenters: An analysis of 1 year of data from an Irish Emergency Department
Authors: Walker Philip A , Cummins Niamh , Collins Niamh
Published: January 2018

Introduction: Frequent presenters (FPs) to the Emergency Department (ED) have been studied heavily in international literature. Many studies suggest that maintaining services for this cohort of patients is wasteful and detracts from the needs of nonfrequent presenters. In this study we aim to describe the characteristics of FPs to the ED. We review data pertaining to frequent ED use, demographics of FPs, their preferred methods of arrival to the ED and their social living arrangements. FP's tend to rely heavily on other services as well as the ED and primary care. Methods: A systematic retrospective review of FPs attendance was performed. Results: FPs accounted for 3.9% (n=1231) of total ED attendance. The age of the FP population ranged from 19- 94 (Median = 45.5, SD 18.422). Increased ED attendance was positively associated with younger age groups. The age category accounting for the highest ED attendance was those aged between 19-35 years. From the 152 (100%) FPs, 50.7% (n=77) were males and 49.3% (n=75) were female. When the living arrangements of FPs were examined, 40.1% (n=61) lived with family, 37.5% (n=57) lived alone, 12.5% (n=19) resided in residential care while data on 9.9% (n=15) FPs was unknown. A Chi-squared analysis was computed to determine if age showed any significant correlation with living arrangements. The findings were not significant as X2 =2.148 (df3, p=0.542). Conclusions: FP's are positively associated with being young and often present with true medical needs. Many believe that frequent presentation is positively associated with free health care and living alone this is not the case. FP's are more likely to live with family and up to 17% of FP attendances have been as a result of primary care referral. FPs also present frequently to the ambulance service with almost 50% utilising the service for transport to the ED.
Rain forests and movement ecology of neotropical primates
Authors: Madden Derek S , Madden Erinn , Madden Sierra
Published: January 2018

Movement ecology of arboreal monkeys in Central America involves the action of diverse body postures to address challenges in rain forests, where scattered resources and complex habitat structure demand that a primate frequently employ extreme physical finesse to survive. What is not clearly understood about this area of study is the connection between primate body postures as responses to specific types of forest architecture and how forest structure may influence a monkey’s continued capacity for wide-ranging mobility over time. We studied tree canopy structure and branch connectivity associated with the movement ecology of black-handed spider monkeys (Ateles geoffroyi), mantled howling monkeys (Alouatta palliata), Geoffroy’s tamarins (Saguinus geoffroyi), and white-faced capuchins (Cebus capucinus) in Panama and Costa Rica. Laboratory study of primate cadaver pelvises was done at UC Davis, Oregon Osteology Lab, and the Denver Museum. Rain forests appear to induce wide-ranging leg movements in wild neotropical monkeys that were not observed in the same species of monkeys inhabiting artificial environments. We also found that a wild primate employs frequent wide-ranging leg movement that result in widely dispersed contacts between the articulating surfaces within the hip, potentially maintaining cartilage and contributing to the longevity of that joint. Thus, a connection may exist between rain forests, the leg action of wild monkeys, and the continued capacity to move over time in this group of long-lived animals.
Ophiacodon long bone histology: the earliest occurrence of FLB in the mammalian stem lineage
Authors: Shelton Christen , Sander P. Martin
Published: January 2018

The origin of mammalian endothermy has long been held to reside within the early therapsid groups. However, shared histological characteristics have been observed in the bone matrix and vascularity between Ophiacodontidae and the later therapsids (Synapsida). Historically, this coincidence has been explained as simply a reflection of the presumed aquatic lifestyle of Ophiacodon or even a sign of immaturity. Here we show, by histologically sampling an ontogenetic series of Ophiacodon humeri, as well as additional material, the existence of true fibrolamellar bone in the postcranial bones of a member of ‘Pelycosauria’. Our findings have reaffirmed what previous studies first described as fast growing tissue, and by proxy, have disproven that the highly vascularized cortex is simply a reflection of young age. This tissue demonstrates the classic histological characteristics of true fibrolamellar bone (FLB). The cortex consists of primary osteons in a woven bone matrix and remains highly vascularized throughout ontogeny providing evidence to fast skeletal growth. Overall, the FLB tissue we have described in Ophiacodon is more derived or “mammal-like” in terms of the osteonal development, bone matrix, and skeletal growth then what has been described thus far for any other pelycosaur taxa. Ophioacodon bone histology does not show well-developed Haversian tissue. With regards to the histological record, our results remain inconclusive as to the preferred ecology of Ophiacodon, but support the growing evidence for an aquatic lifestyle. Our findings have set the evolutionary origins of modern mammalian endothermy and high skeletal growth rates back approximately 20 M.Y. to the Early Permian, and by phylogenetic extension perhaps the Late Carboniferous.
Quorum sensing and genomic studies of a marine bacterium Vibrio variabilis strain T01
Authors: Chan Kok-Gan , Mohamad Nur Izzati
Published: January 2018

Vibrio variabilis strain T01 was isolated from the coastal waters in Hulu Selangor, Malaysia and its genome sequenced. This curved gram-negative bacterium shows cell-to-cell communication properties. The characteristics of the sequenced genome and its annotation processes are described here. The finished assembled whole genome of T01T exhibits genome size of 4,529,728 bp in 83 contigs with 46.22% G+C content, 4053 protein coding genes and 94 RNA genes. The whole genome analysis revealed the presence of quorum sensing signalling molecule synthase gene (luxM) which is crucial to understand the quorum sensing dependent phenotypes in this isolate.
An aerial view: Insights into the effects of ecotourism on the behavior of whale sharks (Rhincodon typus) in Seychelles
Authors: Bluemel Joanna K. , French Georgia C.A. , Rowat David
Published: January 2018

Background: Worldwide, whale shark encounters are a highly sought ecotourism activity. Encounter Codes are implemented to help reduce anthropogenic disturbances. To assess their design and effectiveness, aerial behavioral surveys provide an excellent platform to identify behaviors with little or no observer induced bias. Methods: Five-minute focal-animal behavioral surveys were conducted during micro-light aerial surveys of whale sharks in Seychelles, both in the absence (n=26) and presence (n=24) of Marine Conservation Society, Seychelles research/ecotourism boats and in-water swimmers (following boat and in-water Encounter Codes). Whale shark behaviors with no anthropogenic influences were identified from encounters without boats and recorded as the percentage of survey time. Ordinal logistic regression (OLR) was used to determine whether the proportion of time sharks spent on the surface was dependent upon environmental, morphometric and/or anthropogenic predictors. Differences between the surface swimming time before and after arrival of a boat were also assessed using a paired t-test. Results: The altitude of the aircraft was not found to influence whale shark behavior, neither did environmental factors. There was a significant probability of whale sharks spending shorter periods of time swimming on the surface when in the presence of boats and in-water swimmers (OLR p-value<0.001, paired t-test p-value<0.001). Smaller-sized sharks spent considerably longer periods of time on the surface than larger sharks (p-value<0.05), which was more evident in the absence of anthropogenic influences. Conclusions: Aerial survey methods permit monitoring of behavior without observer induced bias, enabling critical evaluation of encounter management. Boat presence and in-water swimmers did affect the behavior of sharks suggesting that experimental examination of encounter regulations can help determine optimal restrictions to minimize the disturbance to this protected species.