bluuebunny/crossref_metadata_2025 huggingface dataset:
10. Evaluación de las competencias del docente bajo la percepción de los estudiantes de la escuela profesional de Administración de la Universidad Nacional Santiago Antúnez de Mayolo, 2016
Authors: Peláez Díaz Guillermo , Vílchez Cárcamo Juan , Valderrama Plasencia Lorenzo , Carbajulca Milla Milady
Published: November 2018

Determinar la percepción que tienen los alumnos sobre las competencias del docente de la Escuela de Administración de la Universidad Nacional Santiago Antúnez de Mayolo, según los factores de planificación, interacción didáctica del proceso de enseñanza aprendizaje y valoración del proceso de enseñanza aprendizaje. El diseño de la investigación es no experimental, transversal y descriptivo, la muestra equivale a 219 alumnos de la escuela de Administración del semestre 2016-II, seleccionados mediante el muestreo aleatorio simple. Los resultados del presente estudio muestran que los alumnos en un 57% han percibido las competencias de los docentes a nivel general como bueno, lo que significa una aproximación significativa del proceso de enseñanza/aprendizaje de la escuela profesional de Administración, de acuerdo a las exigencias de la Superintendencia Nacional de Educación Superior Universitaria, en el marco del sistema de aseguramiento de la calidad y en aras de lograr el licenciamiento en la escuela profesional de Administración.
Efecto de dos preparados probiótico sobre los parámetros productivos y reducción de diarreas en cerdos pre y post destete
Authors: Miranda José E. , Marín Alfredo , Baño Darío , Hidalgo Luis
Published: November 2018

Evalúa la contribución alimenticia de dos biopreparados probióticos sobre los parámetros productivos y reducción de diarreas en cerdos pre y post destete. Se realizaron 2 experimentos, se utilizaron 14 cerdos híbridos CC21 (Yorkshire – Landrace/ L35 Duroc) en primero y 42 en segundo respectivamente. Se confeccionaron grupos (control y dos en estudio), peso y edad homogéneos, todos en iguales condiciones de manejo y alimentación, Bioprepado A: contenía leche ácida y Biopreparado B: cultivo mixto de baterías y levaduras. La dosis aplicada fue 3 y 5 mL por animal en días alternos, vía oral, durante 33 y 35 días respectivamente. En los dos experimentos realizados, los animales con mejores resultados fueron los aplicados biopreparado B, en los parámetros ganancia de peso 7.8 kg, ganancia media diaria 223 g en el primer experimento y 5.8 kg, 113 g y 6.5% de eficiencia alimenticia respectivamente en el segundo, todos sobre grupo control. Los animales tratados con biopreparados se logró reducir los trastornos diarreicos hasta 8 y 3% respectivamente. El uso de biopreparados probióticos es económico y rentable para las categorías estudiadas; además se logra mejorar los indicadores bioproductivos y la salud del animal.
Evaluación comparativa de ocho variedades de papa (Solanum tuberosum) en el centro poblado de Uchuyacu distrito y provincia de Huaraz departamento de Áncash 2016-2017
Authors: Ramírez Maldonado José , Mejía Anaya Teofanes , Fernández López Carlos
Published: November 2018

El objetivo fue comprobar el mejor rendimiento de ocho variedades de papa en una determinada altitud y a condiciones ecológicas sobre los 2.800 m.s.n.m. El diseño experimental utilizado ha sido el diseño de bloque completamente al azar, la instalación del cultivo se realizó el 5 de noviembre de 2016, se cosechó el 28 de mayo de 2017. Las variedades utilizadas fueron: Yungay, Amarilis, Huayro, Canchan, Perricholi, Milagros, Marina y Kori-INIA. Se realizó un abonamiento a razón de N = 180 kg g/ha., P =180 kg/ha. y K = 120 kg/ha mezclado con 3 Tm/ha de guano de corral de vacuno. Las variedades que destacaron con un óptimo rendimiento de acuerdo a la prueba de comprobación de medias de Tukey, con diferencias estadísticamente significativas al 1%, fueron: la variedad Perricholi con 32.020 Tm/ha promedio de rendimiento, seguido por Kori INIA con 27.979 Tm/ha el menor rendimiento lo tiene la variedad Huayro con solamente 19.374 Tm/ha. La información de estos resultados permitirá a los agricultores adoptar decisiones acertadas evitando riesgos de pérdidas durante la siembra de este cultivo.
Relación entre la percepción de la formación basada en competencias y el logro de las competencias comunicativas de los estudiantes del 5° grado de Educación Secundaria de la Institución Educativa Señor de la Soledad, Huaraz
Authors: Camones Bazan Eling
Published: November 2018

Determina la existencia de una relación entre la percepción de la formación basada en competencias y el logro de las competencias comunicativas de los estudiantes del 5° grado de Educación Secundaria de la Institución Educativa Señor de la Soledad, Huaraz – 2016. Se realizó una investigación de enfoque cuantitativo, de tipo correlacional en una muestra de 63 estudiantes. Para la recolección de información de la primera variable se utilizó un cuestionario de tipo Likert; para la segunda variable se usó tres instrumentos: un test para la dimensión comprensión de textos y dos listas de cotejo tanto para la comprensión y expresión oral, así como para la producción de textos escritos. Los resultados evidenciaron que la percepción de la formación basada en competencias es regular mientras que la mayoría de estudiantes obtuvo el nivel de logro denominado En inicio, concluyendo la existencia de una relación entre las variables de estudio.
Tipificación y modelado gráfico de fincas agrícolas en la cuenca hidrográfica media y baja del río Supe (provincia de Barranca)
Authors: Ayora Garagate Lorenzo , Ramírez Maldonado José , Javier Cabana Luis
Published: November 2018

El objetivo de la investigación fue clasificar y tipificar a los productores que conducen fincas agrícolas con cultivos prevalentes en la cuenca hidrográfica media y baja del río Supe; representar el desempeño actual de las fincas, mediante diagramas cualitativos de flujo; y diseñar mediante modelos de representación gráfica, los sistemas de fincas agrícolas mejorados; proponiendo alternativas técnicas de mejora para los niveles de agroecosistema, finca y región. La metodología utilizada consistió en efectuar el análisis multivariado utilizando un programa estadístico, seleccionando las variables más pertinentes, y determinando las tipologías de productores. Se identificaron limitaciones y potencialidades aplicando el análisis FODA, luego se procedió a jerarquizar los problemas clasificándolos según su grado de causalidad o consecuencia; se determinó cuáles son los problemas activos, pasivos, críticos e indiferentes; y su impacto en los sistemas agropecuarios de la zona en estudio. Para el diseño de las fincas, se construyeron modelos gráficos cualitativos a partir de las tipologías encontradas, considerando los datos económicos y técnicos que caracterizan los sistemas de finca.
Manejo de residuos sólidos y el riesgo laboral en el hospital Víctor Ramos Guardia - Huaraz, 2013
Authors: Norabuena Penadillo Rafael , Tuya Ordóñez Arturo , Vélez Salazar Elizabeth , Menacho López Julio
Published: November 2018

Analiza la relación entre el manejo de residuos sólidos y el riesgo laboral al que están expuestos los trabajadores de salud del hospital Víctor Ramos Guardia (VRG), sobre la base de la norma técnica de gestión y manejo de residuos sólidos del Ministerio de Salud. Para ello, se realizó un estudio descriptivo correlacional, transversal, donde la muestra estuvo conformada por 87 trabajadores asistenciales del hospital VRG de Huaraz, a quienes se les aplicó una encuesta y además se empleó una guía de observación.  Los resultados revelan que, el manejo interno de los residuos sólidos es aceptable (46 %), esto se corrobora al relacionar el manejo de residuos sólidos catalogados como aceptable con el riesgo laboral que fue considerado como mediano. El 32,2 % de los trabajadores están expuestos a un peligroso alto riesgo durante sus actividades diarias, existiendo un preocupante 29,1 % de trabajadores que han sufrido pinchazos como parte de su labor. El almacenamiento primario, intermedio y central de dichos residuos fueron calificados como deficientes, existiendo graves problemas en la segregación que fue evaluado como muy deficiente. Se concluyó que existe una relación significativa entre el manejo inadecuado de residuos sólidos y el riesgo laboral al que están expuestos los trabajadores de salud del hospital Víctor Ramos Guardia.
A Reliability Engineering Approach for Managing Risks in CubeSats
Authors: Menchinelli Alessandro , Ingiosi Francesca , Pamphili Ludovico , Marzioli Paolo , Patriarca Riccardo , Costantino Francesco , Piergentili Fabrizio
Published: November 2018

Besides large-scale space missions, the spread of CubeSats for a variety of applications is increasingly requiring the development of systematic approaches for risk management. Being these applications are based on components with low TRL (Technology Readiness Level) or with limited performance data, it is required to define approaches which ensure a systematic perspective. This paper aims to present a reliability engineering approach based on FMECA (Failure Mode, Effects, and Criticality Analysis) to manage CubeSat reliability data and prioritize criticalities early in the design phase. The approach firstly proposes an alpha-numeric coding system to support the identification and labeling of failure modes for typical CubeSats’ items. Subsequently, each FMECA coefficient (i.e., Severity, Occurrence, Detectability) has been linked to the CubeSat’s structural properties, reducing subjectivity by means of techno-centric proxy indicators. The approach has been validated in the design phases of a 6-Units university CubeSat for the observation of M-Dwarf stars and binary systems. The performed analysis supported the design process and allowed to identify the major criticalities of the CubeSat design, as demonstrated in the extended case study included in the paper. The formalized method could be applied to design procedures for nano-satellites, as well as being expanded for research and development in a variety of space missions.
Improving High-Latitude Rice Nitrogen Management with the CERES-Rice Crop Model
Authors: Zhang Jing , Miao Yuxin , Batchelor William D. , Lu Junjun , Wang Hongye , Kang Shujiang
Published: November 2018

Efficient use of nitrogen (N) fertilizer is critically important for China’s food security and sustainable development. Crop models have been widely used to analyze yield variability, assist in N prescriptions, and determine optimum N rates. The objectives of this study were to use the CERES-Rice model to simulate the N response of different high-latitude, adapted flooded rice varieties to different types of weather seasons, and to explore different optimum rice N management strategies with the combinations of rice varieties and types of weather seasons. Field experiments conducted for five N rates and three varieties in Northeast China during 2011–2016 were used to calibrate and evaluate the CERES-Rice model. Historical weather data (1960–2014) were classified into three weather types (cool/normal/warm) based on cumulative growing degree days during the normal growing season for rice. After calibrating the CERES-Rice model for three varieties and five N rates, the model gave good simulations for evaluation seasons for top weight (R2 ≥ 0.96), leaf area index (R2 ≥ 0.64), yield (R2 ≥ 0.71), and plant N uptake (R2 ≥ 0.83). The simulated optimum N rates for the combinations of varieties and weather types ranged from 91 to 119 kg N ha−1 over 55 seasons of weather data and were in agreement with the reported values of the region. Five different N management strategies were evaluated based on farmer practice, regional optimum N rates, and optimum N rates simulated for different combinations of varieties and weather season types over 20 seasons of weather data. The simulated optimum N rate, marginal net return, and N partial factor productivity were sensitive to both variety and type of weather year. Based on the simulations, climate warming would favor the selection of the 12-leaf variety, Longjing 21, which would produce higher yield and marginal returns than the 11-leaf varieties under all the management strategies evaluated. The 12-leaf variety with a longer growing season and higher yield potential would require higher N rates than the 11-leaf varieties. In summary, under warm weather conditions, all the rice varieties would produce higher yield, and thus require higher rates of N fertilizers. Based on simulation results using the past 20 years of weather data, variety-specific N management was a practical strategy to improve N management and N partial factor productivity compared with farmer practice and regional optimum N management in the study region. The CERES-Rice crop growth model can be a useful tool to help farmers select suitable precision N management strategies to improve N-use efficiency and economic returns.
Use of Gradient-Based Shadow Detection for Estimating Environmental Illumination Distribution
Authors: Lee Sangyoon , Hong Hyunki
Published: November 2018

Environmental illumination information is necessary to achieve a consistent integration of virtual objects in a given image. In this paper, we present a gradient-based shadow detection method for estimating the environmental illumination distribution of a given scene, in which a three-dimensional (3-D) augmented reality (AR) marker, a cubic reference object of a known size, is employed. The geometric elements (the corners and sides) of the AR marker constitute the candidate’s shadow boundary; they are obtained on a flat surface according to the relationship between the camera and the candidate’s light sources. We can then extract the shadow regions by collecting the local features that support the candidate’s shadow boundary in the image. To further verify the shadows passed by the local features-based matching, we examine whether significant brightness changes occurred in the intersection region between the shadows. Our proposed method can reduce the unwanted effects caused by the threshold values during edge-based shadow detection, as well as those caused by the sampling position during point-based illumination estimation.
Hyperfine Anomalies in Gd and Nd
Authors: Persson Jonas R.
Published: November 2018

The hyperfine anomalies in Gd and Nd have been extracted from experimental hyperfine structure constants. In addition to the values of the hyperfine anomaly, new improved values of the nuclear magnetic dipole moment ratios are derived.
The Role of Wine in Modulating Inflammatory Processes: A Review
Authors: Di Lorenzo Chiara , Stockley Creina , Colombo Francesca , Biella Simone , Orgiu Francesca , Dell’Agli Mario , Restani Patrizia
Published: November 2018

Several epidemiological studies associated the consumption of wine with the reduction of the risk factors for cardiovascular disease and certain cancers, as well as for diabetes. These conditions are characterized by inflammatory mechanisms in addition to other biological mechanisms. Acute and chronic inflammation is mediated by a plethora of biomarkers production and pathway activation. Since the health promoting properties of wine in different pathological conditions may include the reduction of inflammation, the aim of this paper was to collect and review the in vitro, in vivo, and human studies performed to evaluate the effects of wine on different models of inflammation. Although great variability in wine intake, period of consumption, and content of phenolic compounds was observed, data from both human and animal studies showed a positive modulation of inflammatory biomarkers (cytokines, coagulation parameters) and oxidative stress (mainly malondialdehyde) involved in cardiovascular function. In addition, some convincing evidence was obtained in different models suggesting a positive modulation of risk factors for gastric and intestinal inflammation. Contradictory results were obtained for metabolic syndrome and type 2 diabetes. To date, no significant paper has been published in the area of immune function. Integrating in vivo data and in vitro studies, the NF-κB pathway has been identified as a critical target for the protective properties of a moderate wine consumption.
Electrochemical Determination of β-Lactoglobulin Employing a Polystyrene Bead-Modified Carbon Nanotube Ink
Authors: Molinari Judith , Florez Laura , Medrano Anahí , Monsalve Leandro , Ybarra Gabriel
Published: November 2018

In this article, we introduce the use of a carboxy-functionalized waterborne carbon nanotube ink for the fabrication of an amperometric biosensor aimed at the quantification of β-lactoglobulin. Detection of this protein from cow’s milk was performed by a sandwich immunoassay onto printed carbon nanotube electrodes. The electrodes were printed using a carbon nanotube ink modified with polystyrene beads containing a high amount of carboxylic groups for protein immobilization. This strategy showed enhanced sensing performance compared to the use of oxidative treatments for the functionalization of electrodes. These electrodes showed an excellent electrochemical behavior, and proteins could be immobilized on their surface via the carbodiimide reaction. These antibody-immobilized carbon nanotube electrodes allowed for the detection of β-lactoglobulin in sub-ppm concentrations.
Sensors Based on Metal Nanoclusters Stabilized on Designed Proteins
Authors: Aires Antonio , Lopez-Martinez Elena , Cortajarena Aitziber L.
Published: November 2018

Among all new nanomaterials, metal nanoclusters (NCs) have attracted special attention due to their interesting optical properties, among others. Metal NCs have been recently studied and used as sensors for different analytes. However, there is a need to explore the potential of these new sensors in a systematic manner and to develop new systems to broaden the possibilities that sensing offers to the industry. In this work, we show the potential use of repeat protein scaffolds as versatile templates for the synthesis and stabilization of various metal NCs, specifically Au, Ag, and CuNCs. The resulting protein-metal NCs hybrids are evaluated as sensors for different stimuli such as temperature, ions, or reactive oxygen species (ROS). Among the three protein-metal NCs, all performed nicely as temperature sensors, AuNCs responded to metal ions, and AgNCs were able to detect ROS.
Towards Simazine Monitoring in Agro-Zootechnical Productions: A Yeast Cell Bioprobe for Real Samples Screening
Authors: Grasso Gerardo , Caracciolo Ludovico , Cocco Giulia , Frazzoli Chiara , Dragone Roberto
Published: November 2018

Simazine is an herbicide that is able to contaminate surface waters, ground waters, and milk/dairy products, thus posing concerns in both environmental health and food safety. A yeast-based bioprobe was utilized to detect simazine in spiked real samples of livestock drinking water and raw cow’s milk. Yeast aerobic respiration was taken as short-term toxicological endpoint. We carried out comparative measures of yeast oxygen consumption between simazine-spiked samples and blank samples. Percentage interference (%ρ) on yeast aerobic respiration was calculated through the comparison of aerobic respiration of simazine-exposed and non-exposed yeast cells. The method was optimized for raw cow’s milk samples by using boric acid as fungistatic agent in order to avoid cellular proliferation. Overall, the results have shown that simazine can be detected up to concentrations five times below the EU legal concentration limits for drinking water (0.02 ppb) and cow’s milk (2 ppb) (%ρ values of 18.53% and 20.43% respectively; %RSD ≤ 15%). Dose-effect relationships of simazine were assessed. The findings of the bioassays match reasonably well with known mechanisms of toxicity and intracellular detoxification in yeast. A correlation between fat content in milk samples and analytical performance of the bioprobe was established. Results suggest the involvement of a matrix effect, presumably due to lipid sequestration of simazine. The yeast-based bioprobe has proved to be sensitive and suitable for the detection of simazine in real samples in concentrations of interest.
Steam Reforming of Methanol over Nanostructured Pt/TiO2 and Pt/CeO2 Catalysts for Fuel Cell Applications
Authors: Papavasiliou Joan , Paxinou Alexandra , Słowik Grzegorz , Neophytides Stylianos , Avgouropoulos George
Published: November 2018

A research and technological challenge for fuel processors integrated with High Temperature Polymer Electrolyte Membrane Fuel Cells (HT-PEMFCs), also known as Internal Reforming Methanol Fuel Cells (IRMFCs), operating at 200–220 °C, is the development of highly efficient catalysts, which will be able to selectively (low CO and other by-products formation) produce the required quantity of hydrogen at these temperatures. In this work, various amounts of platinum were dispersed via deposition-precipitation (DP) and impregnation (I) methods onto the surface of hydrothermally prepared ceria nanorods (CNRs) and titania nanotubes (TNTs). These nanostructured catalysts were evaluated in steam reforming of methanol process targeting the operation level of IRMFCs. The (DP) method resulted in highly (atomically) dispersed platinum-based catalysts, as confirmed with Scanning Transmission Electron Microscopy (STEM) analysis, with a mean particle size of less than 1 nm in the case of 0.35 wt.% Pt/CNRs catalyst. Ultra-fine dispersion of platinum species correlated with the presence of oxygen vacancies, together with the enrichment of CNRs surface with active metallic phase resulted in a highly active catalyst achieving at 220 °C a hydrogen production rate of 5500 cm3 min−1 per g of loaded platinum.
Extracellular Vesicles: A Potential Novel Regulator of Obesity and Its Associated Complications
Authors: Kim Ahlee , Shah Amy S. , Nakamura Takahisa
Published: November 2018

Childhood obesity continues to be a major public health concern. Obesity causes various metabolic complications, including insulin resistance, type 2 diabetes mellitus (T2DM), non-alcoholic fatty liver disease (NAFLD), dyslipidemia, and cardiovascular disease. However, currently, we have a limited understanding of the pathophysiology in the development of these processes. Extracellular vesicles (EVs) are nano-sized vesicles secreted by different cell types that travel to various organ systems carrying molecular and genetic information. These vesicles have been proposed as a novel intercellular communication mode in systemic metabolic regulation and in several pathophysiologic processes. In particular, recent studies indicate that EVs play a critical role in the pathogenesis of obesity and its metabolic complications. In this study, we reviewed the current literature that supports the role of EVs in the regulation of metabolic homeostasis and pathogenesis of obesity and its associated metabolic complications, with a short discussion about future directions in the EV research field.
Climate and the Decline and Fall of the Western Roman Empire: A Bibliometric View on an Interdisciplinary Approach to Answer a Most Classic Historical Question
Authors: Marx Werner , Haunschild Robin , Bornmann Lutz
Published: November 2018

This bibliometric analysis deals with research on the decline and fall of the Western Roman Empire in connection with climate change. Based on the Web of Science (WoS) database, we applied a combination of three different search queries for retrieving the relevant literature: (1) on the decline and fall of the Roman Empire in general, (2) more specifically on the downfall in connection with a changing climate, and (3) on paleoclimatic research in combination with the time period of the Roman Empire and Late Antiquity. Additionally, we considered all references cited by an ensemble of selected key papers and all citing papers of these key papers, whereby we retrieved additional publications (in particular, books and book chapters). We merged the literature retrieved, receiving a final publication set of 85 publications. We analyzed this publication set by applying a toolset of bibliometric methods and visualization programs. A co-authorship map of all authors, a keyword map for a rough content analysis, and a citation network based on the publication set of 85 papers are presented. We also considered news mentions in this study to identify papers with impacts beyond science. According to the literature retrieved, a multitude of paleoclimatic data from various geographical sites for the time of late antiquity indicate a climatic shift away from the stability of previous centuries. Recently, some scholars have argued that drought in Central Asia and the onset of a cooler climate in North-West Eurasia may have put Germanic tribes, Goths, and Huns on the move into the Roman Empire, provoking the Migration Period and eventually leading to the downfall of the Western Roman Empire. However, climate is only one variable at play; a combination of many factors interacting with each other is a possible explanation for the pattern of long-lasting decline and final collapse. Currently, the number of records from different locations, the toolbox of suitable analytic methods, and the precision of dating are evolving rapidly, contributing to an answer for one of the most classic of all historical questions. However, these studies still lack the inevitable collaboration of the major disciplines involved: archeology, history, and climatology. The articles of the publication set analyzed mainly result from research in the geosciences.
Structural, Electronic, Magnetic, Mechanic and Thermodynamic Properties of the Inverse Heusler Alloy Ti2NiIn Under Pressure
Authors: Yang Tie , Cao Jieting , Wang Xiaotian
Published: November 2018

Structural, electronic, magnetic and mechanic properties of the inverse Heusler alloy Ti2NiIn under different pressure are systematically studied with density functional theory (DFT). The equilibrium lattice constant and electronic band structure at null pressure are obtained to be consistent with previous work. Under currently applied static pressure from 0 GPa to 50 GPa, it is found that the half-metallicity of the material is maintained and the total magnetic moment (Mt) is kept at 3 µB, which obeys the Slater–Pauling rule, Mt = Zt − 18, where Zt is the total number of valence electrons. Besides, the effect of the tetragonal distortion was studied and it is found that the magnetic property of Ti2NiIn is almost unchanged. Several mechanical parameters are calculated including three elastic constants, bulk modulus B, Young’s modulus E, and shear modulus S and the mechanical stability is examined accordingly. Furthermore, the thermodynamic properties, such as the heat capacity CV, the thermal expansion coefficient α, the Grüneisen constant γ and the Debye temperature ΘD, are computed by using the quasi-harmonic Debye model within the same pressure range at a series of temperature from 0 to 1500 K. This theoretical study provides detailed information about the inverse Heusler compound Ti2NiIn from different aspects and can further lead some insight on the application of this material.
Closing the Door on Quantum Nonlocality
Authors: Kupczynski Marian
Published: November 2018

Bell-type inequalities are proven using oversimplified probabilistic models and/or counterfactual definiteness (CFD). If setting-dependent variables describing measuring instruments are correctly introduced, none of these inequalities may be proven. In spite of this, a belief in a mysterious quantum nonlocality is not fading. Computer simulations of Bell tests allow people to study the different ways in which the experimental data might have been created. They also allow for the generation of various counterfactual experiments’ outcomes, such as repeated or simultaneous measurements performed in different settings on the same “photon-pair”, and so forth. They allow for the reinforcing or relaxing of CFD compliance and/or for studying the impact of various “photon identification procedures”, mimicking those used in real experiments. Data samples consistent with quantum predictions may be generated by using a specific setting-dependent identification procedure. It reflects the active role of instruments during the measurement process. Each of the setting-dependent data samples are consistent with specific setting-dependent probabilistic models which may not be deduced using non-contextual local realistic or stochastic hidden variables. In this paper, we will be discussing the results of these simulations. Since the data samples are generated in a locally causal way, these simulations provide additional strong arguments for closing the door on quantum nonlocality.
Coherent Precipitation and Strengthening in Compositionally Complex Alloys: A Review
Authors: Wang Qing , Li Zhen , Pang Shujie , Li Xiaona , Dong Chuang , Liaw Peter K.
Published: November 2018

High-performance conventional engineering materials (including Al alloys, Mg alloys, Cu alloys, stainless steels, Ni superalloys, etc.) and newly-developed high entropy alloys are all compositionally-complex alloys (CCAs). In these CCA systems, the second-phase particles are generally precipitated in their solid-solution matrix, in which the precipitates are diverse and can result in different strengthening effects. The present work aims at generalizing the precipitation behavior and precipitation strengthening in CCAs comprehensively. First of all, the morphology evolution of second-phase particles and precipitation strengthening mechanisms are introduced. Then, the precipitation behaviors in diverse CCA systems are illustrated, especially the coherent precipitation. The relationship between the particle morphology and strengthening effectiveness is discussed. It is addressed that the challenge in the future is to design the stable coherent microstructure in different solid-solution matrices, which will be the most effective approach for the enhancement of alloy strength.
Assessing the Relevance of Specific Response Features in the Neural Code
Authors: Eyherabide Hugo Gabriel , Samengo Inés
Published: November 2018

The study of the neural code aims at deciphering how the nervous system maps external stimuli into neural activity—the encoding phase—and subsequently transforms such activity into adequate responses to the original stimuli—the decoding phase. Several information-theoretical methods have been proposed to assess the relevance of individual response features, as for example, the spike count of a given neuron, or the amount of correlation in the activity of two cells. These methods work under the premise that the relevance of a feature is reflected in the information loss that is induced by eliminating the feature from the response. The alternative methods differ in the procedure by which the tested feature is removed, and the algorithm with which the lost information is calculated. Here we compare these methods, and show that more often than not, each method assigns a different relevance to the tested feature. We demonstrate that the differences are both quantitative and qualitative, and connect them with the method employed to remove the tested feature, as well as the procedure to calculate the lost information. By studying a collection of carefully designed examples, and working on analytic derivations, we identify the conditions under which the relevance of features diagnosed by different methods can be ranked, or sometimes even equated. The condition for equality involves both the amount and the type of information contributed by the tested feature. We conclude that the quest for relevant response features is more delicate than previously thought, and may yield to multiple answers depending on methodological subtleties.
The Mathematics Teacher Exchange and ‘Mastery’ in England: The Evidence for the Efficacy of Component Practices
Authors: Boylan Mark , Maxwell Bronwen , Wolstenholme Claire , Jay Tim , Demack Sean
Published: November 2018

‘Mastery’ is central to current policy in mathematics education in England, influenced by East Asian success in transnational assessments. We scrutinise the prospects for mastery pedagogies to improve pupil attainment in English primary schools. The Mathematics Teacher Exchange (MTE)—an element of the mastery innovation—involves teachers visiting Shanghai and then hosting Shanghai teachers in their schools. Informed by programme evaluation, core component practices are analysed, which were implemented by schools belonging to the first cohort of MTE schools. These consist of: varied and interactive teaching; meaningful and coherent mathematical activity; and full curriculum access for all. These elements are supported, optimally, by collaborative, embedded, and mathematically focused professional development. Details of the implemented pedagogy and forms of professional development are reported. Differences from prevailing practice in primary mathematics in England are highlighted. Evidence is reviewed from quasi-experimental trials, reviews and meta-analyses, and rigorous observational studies of the efficacy of practices similar to the MTE mastery pedagogy components in order to assess the prospects for increases in pupil attainment. The analysis suggests that many of the specific practices, if considered individually, have the potential to improve attainment, though overall policy ambitions may not be realised. Based on the review, component practices are identified for which existing evidence justifies immediate implementation by schools and teachers. In addition, practices that would benefit from further testing and evaluation are highlighted.
Continuous Hydrothermal Liquefaction of Biomass: A Critical Review
Authors: Castello Daniele , Pedersen Thomas Helmer , Rosendahl Lasse Aistrup
Published: November 2018

Hydrothermal liquefaction (HTL) of biomass is emerging as an effective technology to efficiently valorize different types of (wet) biomass feedstocks, ranging from lignocellulosics to algae and organic wastes. Significant research into HTL has been conducted in batch systems, which has provided a fundamental understanding of the different process conditions and the behavior of different biomass. The next step towards continuous plants, which are prerequisites for an industrial implementation of the process, has been significantly less explored. In order to facilitate a more focused future development, this review—based on the sources available in the open literature—intends to present the state of the art in the field of continuous HTL as well as to suggest means of interpretation of data from such plants. This contributes to a more holistic understanding of causes and effects, aiding next generation designs as well as pinpointing research focus. Additionally, the documented experiences in upgrading by catalytic hydrotreating are reported. The study reveals some interesting features in terms of energy densification versus the yield of different classes of feedstocks, indicating that some global limitations exist irrespective of processing implementations. Finally, techno-economic considerations, observations and remarks for future studies are presented.
Probabilistic Load Flow Method Based on Modified Latin Hypercube-Important Sampling
Authors: Li Quan , Wang Xin , Rong Shuaiang
Published: November 2018

The growing amount of distributed generation has brought great uncertainty to power grids. Traditional probabilistic load flow (PLF) algorithms, such as the Monte-Carlo method (MCM), can no longer meet the needs of efficiency and accuracy in large-scale power grids. Latin Hypercube Sampling (LHS) develops a sampling efficiency and solves the correlation problem of distributed generation (DG) access nodes for accuracy analyses. In this paper, a modified Latin Hypercube-Important Sampling method is proposed for higher efficiency and precision by using the importance sampling method before LHS and the Cholesky decomposition method in correlation calculations. The simulation results are presented using a modified IEEE 30-bus system and are compared with traditional MCM and LHS.
Assessment of Volatile Compounds Evolution, Antioxidant Activity, and Total Phenolics Content during Cold Storage of Pomegranate Beverage Fermented by Lactobacillus paracasei K5
Authors: Mantzourani Ioanna , Kazakos Stavros , Terpou Antonia , Mallouchos Athanasios , Kimbaris Athanasios , Alexopoulos Athanasios , Bezirtzoglou Eugenia , Plessas Stavros
Published: November 2018

A recently isolate from feta type cheese, potential probiotic strain Lactobacillus paracasei K5, was applied for pomegranate juice (Punica granutum L.) fermentation. Fermentations were carried out for 24 h followed by the storage of pomegranate juices at 4 °C for 4 weeks. The parameters examined were a composition of volatile compounds, antioxidant activity, total phenolic content, and consumers’ acceptance. The results were encouraging showing that lactic acid fermentation enhanced the composition of volatile compounds even at the fourth week of storage. Increased antioxidant activity (151.44 mg TE/100 mL at the second week) and total phenolics content (285 mg GAE/100 mL at the third week) were observed for all the storage times compared to the initial pomegranate beverage. The fermented pomegranate beverage received better scores for the last 3 weeks of cold storage compared to the non-fermented one. Likewise, L. paracasei K5 was proved to be suitable for the production of functional pomegranate beverages with enhanced aromatic characteristics and high nutritional value.
Improving Ventilation Efficiency for a Highly Energy Efficient Indoor Swimming Pool Using CFD Simulations
Authors: Rojas Gabriel , Grove-Smith Jessica
Published: November 2018

The operation of a typical indoor swimming pool is very energy intensive. Previous studies have shown that high quality thermal building envelopes, i.e., with high levels of insulation and airtightness, make it possible to rethink conventional ventilation concepts. Due to the reduced condensation risk in and on envelopes of high thermal quality, ventilation design can be optimized for indoor air quality rather than for averting condensation on the facade. This work investigates different air distribution concepts for an existing swimming pool via computational fluid dynamics (CFD) simulations to evaluate their ventilation efficiency. To reduce modelling and computational resources, the velocity and turbulence fields produced by the swirl-diffusers are determined in a set of separate CFD simulations and incorporated into the swimming pool models. The results show that the ventilation efficiency in the examined swimming pool could potentially be improved with various alternative air distribution concepts, therefore improving the indoor air quality. Although the results seem plausible and compare well with the limited measurement data of air humidity, a more formal experimental validation is still needed before generalizing recommendations.
Precious Metal Enrichment at the Myra Falls VMS Deposit, British Columbia, Canada
Authors: Marshall Daniel , Nicol Carol-Anne , Greene Robert , Sawyer Rick , Stansell Armond , Easterbrook Ross
Published: November 2018

Gold, present as electrum, in the Battle Gap, Ridge North-West, HW, and Price deposits at the Myra Falls mine, occurs in late veinlets cutting the earlier volcanogenic massive sulphide (VMS) lithologies. The ore mineral assemblage containing the electrum comprises dominantly galena, tennantite, bornite, sphalerite, chalcopyrite, pyrite, and rarely stromeyerite, and is defined as an Au-Zn-Pb-As-Sb association. The gangue is comprised of barite, quartz, and minor feldspathic volcanogenic sedimentary rocks and clay, comprised predominantly of kaolinite with subordinate illite. The deposition of gold as electrum in the baritic upper portions of the sulphide lenses occurs at relatively shallow water depths beneath the sea floor. Primary, pseudosecondary, and secondary fluid inclusions, petrographically related to gold, show boiling fluid inclusion assemblages in the range of 123 to 173 °C, with compositions and eutectic melt temperatures consistent with seawater at approximately 3.2 wt % NaCl equivalent. The fluid inclusion homogenization temperatures are consistent with boiling seawater corresponding to water depths ranging from 15 to 125 m. Slightly more dilute brines corresponding to salinities of approximately 1 wt % NaCl indicate that there is input from very low-salinity brines, which could represent a transition from subaqueous VMS to epithermal-like conditions for precious metal enrichment, mixing with re-condensed vapor, or very low-salinity igneous fluids.
Pilot of a Charter to Improve Management of Medicines and Oral Care for Residents with Dysphagia in Care Homes
Authors: Morris Jacqueline E. , Hollwey Frances , Hansjee Dharinee , Power Rachel A. , Griffith Richard , Longmore Timothy , Smithard David G. , Dann-Reed Eleanor , Wright David J.
Published: November 2018

Research in care homes has demonstrated that medication management practices in patients with dysphagia and those receiving medicines covertly may be inappropriate, illegal, and potentially cause harm. This paper presents the results of a feasibility study piloting a resident and healthcare professional best practice charter to improve such practices in care home residents with dysphagia. A charter was developed through a multi-professional expert panel, implemented in one care home, and then piloted in 22 homes in England, Wales, and Northern Ireland. A website was setup and developed iteratively to support the process. Care home staff and residents provided initial feedback on the implementation process and on perceived outcomes six months post implementation. A total of 16 (88.9%) out of 18 respondents from nine homes for six months reported a positive response to the charter. More than 80% of responses regarding the implementation process, impact on staff confidence, and perceived usefulness of the charter were positive. Perceived effectiveness and usefulness could, however, be further improved especially the perceived effect on frequency of medication review, which is reliant on external stakeholder involvement. The charter and supporting website were well received with respondents believing that it was useful, staff showing more confidence, and residents having enhanced care. Approaches to enhancing the charter’s effectiveness were identified.
Changes in Human Population Density and Protected Areas in Terrestrial Global Biodiversity Hotspots, 1995–2015
Authors: Cunningham Caitlin , Beazley Karen F.
Published: November 2018

Biodiversity hotspots are rich in endemic species and threatened by anthropogenic influences and, thus, considered priorities for conservation. In this study, conservation achievements in 36 global biodiversity hotspots (25 identified in 1988, 10 added in 2011, and one in 2016) were evaluated in relation to changes in human population density and protected area coverage between 1995 and 2015. Population densities were compared against 1995 global averages, and percentages of protected area coverage were compared against area-based targets outlined in Aichi target 11 of the Convention on Biological Diversity (17% by 2020) and calls for half Earth (50%). The two factors (average population density and percent protected area coverage) for each hotspot were then plotted to evaluate relative levels of threat to biodiversity conservation. Average population densities in biodiversity hotspots increased by 36% over the 20-year period, and were double the global average. The protected area target of 17% is achieved in 19 of the 36 hotspots; the 17 hotspots where this target has not been met are economically disadvantaged areas as defined by Gross Domestic Product. In 2015, there are seven fewer hotspots (22 in 1995; 15 in 2015) in the highest threat category (i.e., population density exceeding global average, and protected area coverage less than 17%). In the lowest threat category (i.e., population density below the global average, and a protected area coverage of 17% or more), there are two additional hotspots in 2015 as compared to 1995, attributable to gains in protected area. Only two hotspots achieve a target of 50% protection. Although conservation progress has been made in most global biodiversity hotspots, additional efforts are needed to slow and/or reduce population density and achieve protected area targets. Such conservation efforts are likely to require more coordinated and collaborative initiatives, attention to biodiversity objectives beyond protected areas, and support from the global community.
Inverse Multiquadratic Functions as the Basis for the Rectangular Collocation Method to Solve the Vibrational Schrödinger Equation
Authors: Kamath Aditya , Manzhos Sergei
Published: November 2018

We explore the use of inverse multiquadratic (IMQ) functions as basis functions when solving the vibrational Schrödinger equation with the rectangular collocation method. The quality of the vibrational spectrum of formaldehyde (in six dimensions) is compared to that obtained using Gaussian basis functions when using different numbers of width-optimized IMQ functions. The effects of the ratio of the number of collocation points to the number of basis functions and of the choice of the IMQ exponent are studied. We show that the IMQ basis can be used with parameters where the IMQ function is not integrable. We find that the quality of the spectrum with IMQ basis functions is somewhat lower that that with a Gaussian basis when the basis size is large, and for a range of IMQ exponents. The IMQ functions are; however, advantageous when a small number of functions is used or with a small number of collocation points (e.g., when using square collocation).
A New Approach to Simulate HSLA Steel Multipass Welding through Distributed Point Heat Sources Model
Authors: Ferreira Dario Magno Batista , Alves Antonio do Nascimento Silva , Cruz Neto Rubelmar Maia de Azevedo , Martins Thiago Ferreira , Brandi Sérgio Duarte
Published: November 2018

Mechanical properties of welded joints depend on the way heat flows through the welding passes. In multipass welding the reheating of the heat affected zone (HAZ) can form local brittle zones that need to be delimited for evaluation. The difficulty lies in the choice of a model that can simulate multipass welding. This study evaluated Rosenthal’s Medium Thick Plate (MTP) and the Distributed heat Sources (DHS) of Mhyr and Gröng models. Two assumptions were considered for both models: constant and temperature-dependent physical properties. It was carried out on a multipass welding of an API 5L X80 tube, with 1016 mm (42″) external diameter, 16 mm thick and half V-groove bevel, in the 3G up position. The root pass was welded with Gas Metal Arc Welding (GMAW) process with controlled short-circuit transfer. The Flux Cored Arc Welding (FCAW) process was used in the filling and finishing passes, using filler metal E111T1-K3M-JH4. The evaluation criteria used were overlapping the simulated isotherms on the marks revealed in the macrographs and the comparison between the experimental thermal cycle and those simulated by the proposed models. The DHS model with the temperature-dependent properties presented the best results and simulated with accuracy the HAZ of root and second welding passes. In this way, it was possible to delimit the HAZ heated sub-regions.