bluuebunny/crossref_metadata_2025 huggingface dataset:
On Values Approximation of Some Special Type Hypergeometric Functions with Irrational Parameters
Authors: Ivankov P. L.
Published: January 2020

In this paper we investigate arithmetic nature of the values of generalized hypergeometric functions and their derivatives. To solve the problem one often makes use of Siegel’s method. The first step in corresponding reasoning is, using the pigeonhole principle, to construct a functional linear approximating form, which has high order of zero at the origin of the coordinates.

A hypergeometric function is defined as a sum of a power series whose coefficients are the products of the values of some rational function. Taken with the opposite sign, the zeroes of a numerator and a denominator of this rational function are called parameters of the corresponding generalized hypergeometric function. If the parameters are irrational it is impossible, as a rule, to employ Siegel’s method. In this case one applies the method based on the effective construction of the linear approximating form.

Additional difficulties arise in case the rational function numerator involved in the formation of the coefficients of the hypergeometric function under consideration is different from the identical unit. In this situation even the availability of the effective construction of approximating form does not enable achieving an arithmetic result yet. In this paper we consider just such a case. To overcome difficulties arisen here we consider the values of the corresponding hypergeometric function and its derivatives at small points only and impose additional restrictions on parameters of the function.
Using Video in Blended Pedagogies to Address Accessibility
Authors: Beevers Grant
Published: January 2020

Besides being the right thing to do, creating an accessible learning experience ensures that educational institutions are providing equitable opportunities for the many students with a disability. Millions of people live with disabilities, not all of them easily visible. Video has become a major component of the digital workplace, and offers some challenges to some people with disabilities.

But not only are there ways to overcome these challenges, video itself can aid in providing an effective learning experience for all students. The most common topic to come up for increasing video accessibility is around captions and transcripts. Video unites sight and sound. Especially in an education environment, removing the sound usually makes a video mostly pointless. It’s not enough for the content to be accessible, though. The video platform itself has to be accessible if you genuinely want to increase accessibility.The key to increasing accessibility is flexibility. If you can offer students multiple choices – with captions or without, with default-size icons or with larger and higher contrast icons, live or on-demand, in person or remote – they can choose for themselves the accommodations they need to do their best work.

Many students have disabilities they may not wish to disclose. The way one person is affected by a disability may be different from how another person with a similar disability is affected. In fact, a person may feel impacted by their disability in different ways from day to day, such as when someone with chronic pain has a “good” or a “bad” day.

In this brief presentation, Grant Beevers, Senior Digital Learning Specialist with Kaltura, will outline how organisations can address accessibility through best practice in video design and publishing, whether it’s embedded video content in course design, content imported from external websites, and common use cases including personal and lecture capture.
Do barriers to innovation impact changes in innovation activities of firms during business cycle? The effect of the Polish green island
Authors: Jakimowicz Aleksander , Rzeczkowski Daniel
Published: January 2020

Research background: There is no doubt that innovation is an important source of economic growth. In the assessment of the innovative activity of Polish industrial processing enterprises, two opposing views can be found. The first indicates the exogenous shock resulting from the global financial crisis and the associated innovation crisis and the subsequent period of innovative pessimism. The second shows the Polish economy as the European Green Island due to strong and uninterrupted economic growth over the past 27 years, controlled inflation, and reduction of unemployment as well as increase of the citizens? well-being. In these conditions, an interesting research gap appeared, which is worth filling, at the centre of which there are factors determining the innovative activity of enterprises, and in particular the role and importance of innovation barriers in various phases of the business cycle.
Purpose of the article: The aim of the research is to determine the impact of innovation barriers and degrees of their importance on the innovation activity of Polish industrial processing enterprises during the business cycle. The time frame of the analysis covers three phases of the cycle: the prosperity period of 2004?2006, the global financial crisis of 2008?2010 and the recovery from 2012?2014.
Methods: Pearson?s ?2 independence test and correspondence analysis were used for data analysis. The research results are presented in a graphical form of biplots that describe the coexistence of three types of variables: (1) types of enterprises and ownership sectors, (2) effects or objectives of innovative activity, and (3) innovation barriers and reasons for the lack of innovation. The basis of calculations were three databases covering the mentioned periods.
Findings & Value added: High resistance of innovative activity of Polish industrial processing enterprises to economic fluctuations has been demonstrated. Innovation barriers and degrees of their importance had little impact on the operations of enterprises in the first of the analysed periods, when prosperity was booming. The impact of the global financial crisis on innovation activities proved to be counterintuitive, as enterprises have continuously achieved their goals and the importance of innovation barriers has diminished even more. In the third period, innovation barriers no longer had any significance for the innovation activities of enterprises. The phenomenon of a gradual decline in the importance of innovation barriers, regardless of the phases of the business cycle, was called the Polish Green Island Effect. The relationship found is a peculiarity which is probably unprecedented in recent world economic history.
Comparación de la progresividad del sistema fiscal en el tiempo: teoría y aplicación en México
Authors: Huesca Reynoso Luis , Araar Abdelkrim
Published: January 2020

La evaluación de la progresividad de un sistema fiscal es relevante para tener una idea general de la magnitud de la redistribución. Se investiga la evolución de la progresividad en el tiempo y cómo la política fiscal del gobierno afecta a su diseño en México, así como la dinámica de la progresividad del sistema fiscal en el periodo 2002-2012. Se utiliza un método de comparación de la progresividad con una aplicación no paramétrica y un soporte común de comparación en el tiempo. Se detecta un aumento en la progresividad con altos niveles de polarización y desigualdad con un impacto reductor en sus niveles.
Un enfoque Cópula-TGARCH de la dependencia condicional entre el precio del petróleo y el índice del mercado de valores: el caso de México
Authors: Lorenzo Valdés Arturo , Armenta Fraire Leticia , Durán Vázquez Rocío
Published: January 2020

En este artículo se aplican las cópulas Clayton y Gumbel con el modelo TGARCH para la distribución marginal de los rendimientos con el objeto de describir la dependencia condicional en las colas entre el precio del petróleo y el índice del mercado de valores de México (IPC, índice de precios y cotizaciones) usando datos semanales para el período de 2010 a 2014. Se encontró que cada una de las series analizadas del índice y del precio de petróleo puede describirse adecuadamente con el modelo propuesto TGARCH y que existe algún grado de dependencia condicional en las colas, presentándose una mayor volatilidad en la cola superior (derecha) y más estabilidad en la cola inferior (izquierda).
Impacto de la influenza AH1N1 en el mercado mexicano de carne de cerdo
Authors: Ayala Edgardo , Chapa Joana
Published: January 2020

Se estiman los efectos de la influenza AH1N1 en el consumo de carne de puerco a través de un modelo de demanda de consumo AIDS (por sus siglas en inglés) para el consumo de carne en México. Adicionalmente, los efectos indirectos a través de la economía mexicana son calculados con un modelo de equilibrio general. Se concluye que el presunto riesgo de contraer la influenza AH1N1 mediante el consumo de carne de puerco provocó pérdidas económicas de 94 millones de dólares. El rumor afectó a los sectores: porcino, de venta de granos y de manufactura de alimentos, bebidas y tabaco. Las familias pobres rurales fueron las más afectadas.
Un índice de precariedad laboral de largo plazo para México
Authors: García Díaz Rocío , Prudencio Daniel
Published: January 2020

Se presenta un índice multidimensional que considera una serie de dimensiones e indicadores asociados con la cantidad y calidad del empleo de las personas. El artículo se focaliza en aspectos microeconómicos del mercado laboral que complementan las dimensiones macroeconómicas del empleo y ayudan a caracterizar completamente situaciones del mercado laboral a nivel individual. Se utiliza un análisis multidimensional que considera la persistencia y duración de ciertas características del hogar que pueden predisponer al desempleo, a largo plazo, de los individuos. Con base en la Encuesta nacional de ocupación y empleo (ENOE), durante los periodos 2007 y 2014 se analiza la dinámica de la precariedad laboral a largo plazo en México.
Pronósticos de la estructura temporal de las tasas de interés en México con base en un modelo afín
Authors: Elizondo Rocío
Published: January 2020

Se muestra que un modelo afín permite igualar o mejorar los pronósticos de la estructura temporal de las tasas de interés en México. El modelo de pronóstico se especifica como una relación lineal entre las tasas de interés y tres factores observables, para vencimientos de 1-60 meses. Los pronósticos del modelo afín son comparados con estos de una tasa forward, un AR (1), un VAR (1) y una caminata aleatoria. El modelo afín tiene un desempeño comparable con los otros modelos para horizontes de 12- y 18- meses, con excepción de la caminata aleatoria, Que presenta menores pronósticos para los vencimientos de 24- y 36- meses. No obstante, el modelo afín mejora su desempeño de pronóstico para los horizontes de 24- meses, principalmente para vencimientos de 60-meses
Contribuciones de campaña y bienes públicos locales en una federación
Authors: Ponce Rodríguez Raúl Alberto
Published: January 2020

Se desarrolla un modelo de economía política para estudiar la provisión descentralizada de bienes públicos locales (BPLs). Se compara una economía con y sin contribuciones de campaña de los votantes: en la primera economía, los gobiernos locales proveen BPLs que no son Pareto eficientes y no maximizan las ganancias atribuibles a diferenciar los BPLs de acuerdo con la heterogeneidad inter-regional de preferencias de los votantes. Para una economía con contribuciones de campaña, los BPLs, con y sin externalidades, son Pareto eficientes y los gobiernos locales maximizan las ganancias atribuibles a diferenciar la provisión de BPLs de acuerdo con la heterogeneidad inter-regional de preferencias.
Suavizamiento conjunto del PIB y la tasa de desempleo con un filtro HP bivariado
Authors: Islas Alejandro , Guerrero Víctor M.
Published: January 2020

Se considera el problema de estimar conjuntamente las tendencias y los ciclos no observables de una serie de tiempo bivariada, en el contexto macroeconómico de la Ley de Okun, para relacionar las brechas del producto y la tasa de desempleo. La estimación se realiza con un filtro de Hodrick-Prescott bivariado que estima simultáneamente la correlación entre los ciclos. La contribución principal de este enfoque es que se puede controlar la suavidad de las tendencias al fijar un parámetro de suavizamiento en forma apropiada. La ilustración empírica utiliza datos del PIB y de la tasa de desempleo de Estados Unidos.
Productividad y eficiencia técnica de la industria manufacturera regional de México, 1960-2013: un enfoque panel de frontera estocástica
Authors: Borrayo López Rafael , Mendoza González Miguel Ángel , Castañeda Arriaga J. Manuel
Published: January 2020

Se analizan las principales fuentes de crecimiento de la productividad total de los factores (PTF) de la industria regional en México mediante un modelo de frontera estocástica e ineficiencia técnica a la Battese y Coelli (1992, 1995), aplicando el método de descomposición de la PTF propuesto por Nishimizu y Page (1982) y Kumbhakar, Denny y Fuss (2000). Los resultados muestran que el cambio tecnológico y el cambio en la eficiencia técnica son las dos principales fuentes que explican las tendencias observadas en las tasas de cambio de la PTF regional de México entre 1960 y 2013.
El estado de bienestar como un bien público no excluible
Authors: Accinelli Elvio , Salas Osvaldo
Published: January 2020

Se analiza la posible evolución de una economía en la que, hasta cierto momento, el Estado actuaba como monopolista en la prestación de un conjunto de servicios públicos y que, ante un cambio en la situación económica, se plantea la interrogante acerca de que si estos servicios deben seguirse prestando por parte del Estado o bien deben pasar a manos de particulares. Con independencia de la respuesta a tal cuestionamiento, se  supone que dichos servicios deben prestarse sin exclusiones y con la misma calidad a todos los ciudadanos al margen de su riqueza. Este es un principio básico que pauta las economías de los países que, como Suecia, se rigen por las normas del estado de bienestar.
Convergencia de los precios locales en México: un enfoque de pruebas entre pares
Authors: Rodríguez Benavides Domingo , Rodríguez Nava Abigail
Published: January 2020

Se analiza la convergencia de los niveles de precios locales en México a través de un enfoque de pares. Para ello se aplican pruebas de raíces unitarias a los precios relativos de todas las posibles combinaciones de ciudades de diferentes bienes y servicios. Una de las principales virtudes de este enfoque es que no requiere elegir una ciudad de referencia o promedio, como base de los niveles de precios relativos, para el análisis de la estacionariedad. El enfoque se aplica a series mensuales de los índices generales y desagregados de una muestra de precios de bienes y servicios en el periodo 1982-2016. Los resultados permiten rechazar la hipótesis nula de no convergencia entre los precios relativos para la mayoría de los bienes y servicios analizados de las ciudades consideradas, no obstante, la convergencia es hasta cierto punto limitada.
Classificação climática e aptidão agrícola para Bom Jesus-PI em diferentes cenários climáticos
Authors: Fernandes Gabriel Siqueira Tavares , Lima Edivania de Araujo , Lopes Pabrício Marcos Oliveira , Silva Douglas Alberto de Oliveira , Santos Anderson dos , Silva Tecla Ticiane Félix da
Published: January 2020

A caracterização climática de uma região permite a recomendação e a determinação de um melhor manejo de culturas agrícolas. Nesse sentido, objetivou-se identificar mudanças na classificação climática e aptidão agroclimática da cidade de Bom Jesus-Piauí, em diferentes cenários climáticos. O município integra a região do Semiárido Piauiense, possuindo clima quente e úmido. Na composição do balanço hídrico climatológico (BHC), calculado pelo método de Thornthwaite & Mather, utilizaram-se os conjuntos de dados das normais climatológicas de 1961-1990 e 1981-2010, ambas disponibilizadas pelo Instituto Nacional de Meteorologia (INMET). Verificou-se, entre os conjuntos de dados avaliados, um aumento de 1,5°C na temperatura média do ar, redução de 106,7 mm nos totais pluviométricos e um aumento de 350,7 mm na ETP, configurando uma longa estação seca e a presença de deficiência hídrica na maior parte do ano. No que se trata à classificação climática constatou-se uma mudança no tipo climático da região, deixando de ser classificado como Subúmido seco (C1) e passando a ser classificado como Semiárido (D), desta forma o cultivo da banana, caju e sorgo foram afetados pela redução da disponibilidade hídrica da região.
The mediating effect of utility of informal organization between participation of informal organization and job satisfaction
Authors: Kang Minji , Lee Kyehoon , Moon Kwangsu , Oah Shezeen
Published: January 2020

The purpose of the present study was to examine the influence of participation in informal organization on the job satisfaction. This study also attempted to find out the mediating effects of utility of informal organization in the relationship between participation and job satisfaction. Based on previous research, we classified utility into affective, communication, instrumental utility. Data were collected from 206 workers employed in various organizations. It was found that participation in informal organization were significantly related with high job satisfaction. In addition, the toeal utility were fully mediating the relationship between participation and job satisfaction. Affective, communication utilities had full mediating effects and instrumental utility had a partial mediating effect. This finding suggest that organizations should actively support informal organizations and find the way to encourage employees to participate informal organizations.
The effects of learning factor, individual & team network, and team adaptive performance on innovative behavior
Authors: Yoon SeokHyun , Han TaeYoung
Published: January 2020

This study examined the factors that may affect the innovative behavior based on the learning organization theory and the social capital theory. Also, considering the prevalence of the team system in modern organizations, the study was carried out in team context. Specifically, the study investigated the individual-level factors (i.e., continuous learning activity and network centrality) and the team-level factors (i.e., team network density and feedback environment) as predictors of the innovative behavior. The study also tested the moderating roles of the two team factors and the mediation effect of team adaptive performance. Using the survey research method, data were collected from 158 employees in 35 teams. To test the suggested model, multi-level analysis was conducted using the HLM. The results showed positive relationships between continuous learning and innovative behavior at the individual level. and between team feedback environment and team adaptive performance at the team level. The mediation effect of adaptive performance was confirmed only between team feedback environment and innovative behavior, showing that a significant cross-level effect of team adaptive performance on innovative behavior. From the confirmed meso-mediational relationships of the team factors on the innovative behavior, this study provided theoretical and practical implications regarding the innovative behavior at team contexts.
Penapisan Virtual Senyawa Dalam Tanaman Familia Annonaceae Sebagai Ligan Pada Reseptor Estrogen Alfa (ER-α)
Authors: Mulatsari Esti , Mumpuni Esti , Sandy Kevin
Published: January 2020

Annonaceae adalah familia dengan 800 spesies yang tersebar di seluruh dunia. Beberapa penelitian menunjukkan bahwa annonaceae memiliki aktivitas biologis sebagai antikanker dan telah digunakan sebagai obat herbal secara empiris. Pada penelitian ini dilakukan penapisan virtual beberapa struktur senyawa dari tanaman familia Annonaceae. Tujuan penelitian ini adalah untuk menganalisis dan memperoleh kandidat senyawa yang aktif sebagai ligan pada reseptor estrogen alfa yang dapat memicu timbulnya kanker payudara, selanjutnya akan dilakukan elusidasi moda ikatan senyawa representatif aktif dan inaktif untuk melihat interaksi asam-asam amino pada binding site senyawa tersebut. Penelitian ini menggunakan protokol tervalidasi hasil penelitian Anita dkk., 2012 dengan berbagai aplikasi komputasi seperti SPORES, PLANTS, BKchem, OpenBabel dan PyMol. Hasil penapisan virtual menunjukkan bahwa dari 39 kandidat senyawa ada 18 senyawa dari tanaman familia Annonaceae yang memiliki nilai ChemPLP lebih kecil daripada ligan pembanding, artinya ada 18 senyawa yang memiliki afinitas yang lebih baik terhadap reseptor sehingga dapat mencegah timbulnya kanker payudara.
Determination and Quantification of Gallic Acid in
Raw Propolis by High-performance Liquid Chromatography–Diode Array
Detector in Burundi
Authors: Nyandwi Ramadhan , Kılıç Ayşe S. , Çelik Meltem , Oruç Hasan H.
Published: January 2020

Background:
Honey, pollen, and propolis are among the products that
bees process and derive from plants and flowers. Propolis is a resinous
material that bees gather from the buds and bark of some trees and small
plants. Propolis from temperate climates mainly contains phenolic
compounds, in contrast with propolis from tropical climates, which
mainly contains terpenes. This study aimed to determine, characterise,
and quantify the phenolic content of raw propolis from
Burundi. Methods:
In this study, a total of 6 samples were collected from
the provinces of Rumonge, Cibitoke, and Ruyigi in Burundi. Fifteen
phenolic compounds (caffeic acid, ferulic acid, epigallocatechin
gallate, isoferulic acid, cinnamic acid, caffeic acid phenethyl ester,
gallic acid, apigenin, chrysin, galangin, quercetin, kaempherol, rutin
trihydrate, naringenin, and pinocembrin) were used as high-performance
liquid chromatography (HPLC) standards for qualitative and quantitative
analyses of the propolis samples. Results: Among the 15
phenolic compounds checked, only 1 – gallic acid – was detected at a
measurable level using an HPLC-diode array detector system.
Conclusion: In addition
to terpenes, propolis found in sub-Saharan Africa may contain phenolic
compounds. Further advanced investigation of sub-Saharan African
propolis is required for more detailed
characterisation.
Data type Modeling with DFA and NFA as a Lexical Analysis Generator
Authors: Abdulnabi Nisreen L. , Ahmad Hawar B.
Published: January 2020

Lexical analysis helps the interactivity and visualization for active learning that can improve difficult concepts in automata. This study gives an implementation of two frequently used model, NFA for combination of Real and Integer data type and DFA for Double Data Type in Java this chosen model will be implemented using JFLAP. The model will also be tested using JFLAP that will accept at least FIVE (5) inputs and rejected FIVE (5) inputs. These two models are some of the different lexical analyzer generators that have been implemented for different purposes in finite automata.
Integration of Self Organizing Map with MLFF Neural Network to Predict Oil Formation Volume Factor: North Africa Crude Oil Examples
Authors: Algdamsi Hossein , Alkouh Ahmed , Agnia Ammar , Amtereg Ahmed , Alusta Gamal
Published: January 2020

In this paper we introduce for the first time an innovative approach for deriving Oil Formation Volume Factor (Bo) by mean of artificial intelligence method. In a new proposed application Self-Organizing Map (SOM) technology has been merged with statistical prediction methods integrating in a single step dimensionality reduction, extraction of input data structure pattern and prediction of formation volume factor Bo. The SOM neural network method applies an unsupervised training algorithm combined with back propagation neural network BPNN to subdivide the entire set of PVT input into different patterns identifying a set of data that have something in common and run individual MLFF ANN models for each specific PVT cluster and computing Bo. PVT data for more than two hundred oil samples (total of 804 data points) were collected from the north African region representing different basin and covering a greater geographical area were used in this study. To establish clear Bound on the accuracy of Bo determination several statistical parameters and terminology included in the presentation of the result from SOM-Neural Network solution. the main outcome is the reduction of error obtained by the new proposed competitive Learning Structure integration of SOM and MLFF ANN to less than 1 % compared to other method. however also investigated in this work five independents means of model driven and data driven approach for estimating Bo theses are 1) Optimal Transformations for Multiple Regression as introduced by (McCain, 1998) using alternating conditional expectations (ACE) for selecting multiple regression transformations 2), Genetic programing and heuristic modeling using Symbolic Regression (SR) and cross validation for model automatic tuning 3) Optimization by successive alteration of the empirical constant of the correlation parametric form of Standing correlation or any other, 4) Correlation refinement using Rafa Labedi approach tuning existing working correlation of Standing and others for calculating Bo by adjusting constant in the linear trend component of the formula structure of Standing correlation using a subset of the original correlation called correlation variable of formation volume factor this type of correlation refinement was extended and applied to modify any other available correlation to predict Bo 5) Machine learning predictive model (Nearest Neighbor Regression, Kernel Ridge regression, Gaussian Process Regression (GPR), Random Forest Regression (RF), Support Vector Regression (SVM), Decision Tree Regression (DT), Gradient Boosting Machine Regression (GBM), Group modeling data handling (GMDH). Regression Model Accuracy Metrics (Average absolute relative error, R-square), diagnostic plot was used to address the more adequate techniques and model for predicting Bo.
Envelhecimento ativo, qualidade de vida e cognição de idosos: um estudo transversal em uma cidade de Minas Gerais
Authors: Silva Jaqueline Gabriele , Caldeira Caio Godinho , Cruz Gylce Eloisa Cabreira Panitz , Carvalho Luciana Estefani Drumond de
Published: January 2020

Objetivos: Avaliar a associação entre a cognição, a prática de atividade física, a qualidade de vida e investigar a influência dos fatores sociodemográficos em idosos em uma cidade de médio porte no estado de Minas Gerais. Métodos: O estudo foi observacional, transversal e quantitativo. Foram entrevistados 303 idosos. Utilizaram-se uma ficha de identificação, o teste de qualidade de vida WHOQOL-OLD, o Questionário Internacional de Atividade Física (IPAQ) e o Mini-exame do Estado Mental (MEEM). Para a análise, foram aplicados os testes de Kruskal-Wallis e de Mann-Whitney, com significância de p<0,05. Resultados: Ressalta-se a predominância do sexo feminino, na faixa etária de 66 a 70 anos, com escolaridade entre 4 e 8 anos e renda de até dois salários mínimos. A amostra apresentou cognição majoritariamente preservada (n=186; 61%), qualidade de vida regular (n=163; 54%) e se mostrou ativa quanto ao nível de atividade física (n=251; 83%). Idosos ativos apresentaram melhor qualidade de vida, entretanto não houve associação com melhora da cognição. Observou-se que maior idade, menor renda e menor escolaridade se correlacionam com menor nível cognitivo. Conclusão: Notou-se relação positiva entre a qualidade de vida dos idosos e a prática de atividade física.
Avaliação do impacto da hiperglicemia hospitalar em relação à morbimortalidade em pacientes não críticos
Authors: De Moraes Júnior Rudival Faial , Branco Ricardo Chaves , Costa William Rodrigues
Published: January 2020

Objetivo: Avaliar o impacto da hiperglicemia hospitalar nas taxas de mortalidade, tempo de internação e necessidade de suporte em unidade de terapia intensiva (UTI) nos pacientes não críticos hospitalizados nas enfermarias de clínica médica de um hospital público do Pará. Métodos: Estudo quantitativo, transversal, com amostra de 187 pacientes. Os grupos com e sem hiperglicemia foram avaliados quanto ao tempo de internação, necessidade de internação em UTI e óbito. Resultados: Não foram obtidas diferenças estatisticamente significativas que relacionassem a hiperglicemia hospitalar com o prolongamento no tempo de internação, maior necessidade de suporte em UTI e maior mortalidades dos pacientes. Notou-se, porém, que houve uma maior mortalidade entre os pacientes com diagnóstico de hiperglicemia hospitalar sem diagnóstico prévio de diabetes, mesmo que sem diferença estatisticamente significativa. Conclusão: Apesar da literatura relacionar a hiperglicemia com desfechos adversos, o presente estudo não mostrou diferença estatisticamente significativa em relação a duração do tempo de internação, necessidade de atendimento em UTI e mortalidade.
A CycloRGDf(Me-V) Analog as Chemical Probe to Study Integrins Function in Living Cells
Authors: Kapras Vojtech , Slattery Wyatt T. , Menard Frederic
Published: January 2020

We report a chemical probe that can be used to image integrins in living cells. The fluorescent probe was derived from cyclo-RGDf(Me-V), a compound selective for integrins that possess an RGD-binding domain. We describe its synthesis and we demonstrate its use to detect integrin αVβ5 in cells. The probe’s dissociation constant for the integrin αVβ5 protein is 0.18 μM. The probe's activity was validated in murine BV-2 microglial cells using cell engulfment assays, flow cytometry, and confocal fluorescence imaging. This probe will provide access to spatiotemporally resolved studies of RGD-binding integrin function in living cells without the need for genetic modification.
Dewar Benzenoids Discovered In Carbon Nanobelts
Authors: Hanson-Heine Magnus , Rogers David , Woodward Simon , D Hirst Jonathan
Published: January 2020

Here we report the discovery that isomers containing two Dewar benzenoid rings are the preferred form for several sizes of cyclacene. The predicted lower polyradical character and higher singlet-triplet stability that these isomers possess compared with their pure benzenoid counterparts suggests that they may be more stable synthetic targets than the structures which have previously been identified.
Bottom-up Chemoenzymatic Synthesis Towards Novel Fluorinated Cellulose-like Materials
Authors: de Andrade Peterson , Muñoz-García Juan C. , Pergolizzi Giulia , Gabrielli Valeria , Nepogodiev Sergey , Iuga Dinu , Fábián Laszlo , Nigmatullin Rinat , Johns Marcus A. , Harniman Robert , Eichhorn Stephen J. , Angulo Jesús , Khimyak Yaroslav , Field Robert
Published: January 2020

Understanding the fine details of self-assembly of building blocks into complex hierarchical structures represents a major challenge en route to the design and preparation of soft matter materials with specific properties. Enzymatically-synthesised cellodextrins are known to have limited water solubility beyond DP9, a point at which they self-assemble into particles resembling the anti-parallel cellulose II crystalline packing. We have prepared and characterized a series of site-selectively fluorinated cellodextrins of different degrees of fluorination and substitution patterns by chemoenzymatic synthesis. The structural characterization of these materials at different length scales, combining advanced NMR and microscopy methods, showed that multiply 6-fluorinated cellodextrin chains assembled into particles presenting morphological and crystallinity features that are unprecedented for cellulose-like materials. In contrast, the introduction of a single fluorine atom per cellodextrin chain had a minor impact on materials structure. Our work emphasizes the strength of combining chemoenzymatic synthesis, fluorinated building blocks and advanced NMR and microscopy methods for the thorough characterization of hierarchical structures, leading to the controlled design of new biomaterials with specific properties.
Process Intensification of Photochemical Oxidations using a High Throughput Rotor-Stator Spinning Disk Reactor: A Strategy for Scale Up
Authors: Chaudhuri Arnab , Kuijpers Koen P. L. , Hendrix Raoul , Hacking Jasper , Shivaprasad Parimala , Emanuelsson Emma A. C. , Noel Timothy , van der Schaaf John
Published: January 2020

This paper presents a novel high-throughput reactor for intensification of photochemical conversion processes. The photocatalyzed gas-liquid oxidation of α-terpinene to the drug ascaridole with rose-bengal was achieved with throughputs of over 1 kg∙day-1 (71 kg∙day-1∙m-2) under visible light irradiation. The performance of the reactor is correlated to rotation speed, liquid flowrate, gas flowrate, catalyst concentration, substrate concentration, gas holdup, gas bubble size, and energy dissipation rate. The conversion and selectivity increase from 37% to 97% and 75% to 90% respectively with an increase of rotation speed from 100 to 2000 RPM. Compared to conventional photochemical reactors such as the batch reactor or the microreactor, the photo-rotor-stator spinning disk reactor has much higher productivity (270 mmol∙h-1 or 19.2 mol∙h-1∙m-2) and higher selectivity (> 90%), with the latter illustrating the impact of mixing on selectivity. The findings of this study can be used to study, design, optimize and scale photochemical processes using the rotor-stator spinning disk reactor.
Palladium-Catalyzed Diastereo- and Enantioselective Allylic Alkylation of Oxazolones with 1,3-Dienes Under Base-Free Conditions
Authors: Yang Haijian , Xing Dong
Published: January 2020

Herein, we report a highly diastereo- and enantioselective allylic alkylation of oxozolones with 1,3-dienes by palladium-hydride catalyst under base-free conditions. With DTBM-SEGPHOS as the chiral ligand, a series of enantioenriched oxazolones bearing tertiary carbon centers were synthesized from substituted 1,3-dienes via exclusive 1,2-addition with moderate to good diastereoselectivities and high enantioselectivities. When simple 1,3-butadiene was used as the allyl precursor under this base-free catalytic system, 1,4-addition products were obtained in good yields with high regioselectivities.
Internal Fragments Generated by Electron Ionization Dissociation Enhances Protein Top-down Mass Spectrometry
Authors: Zenaidee Muhammad , Lantz Carter , Perkins Taylor , Fu Janine , Jung Wonhyuek , R. Ogorzalek Loo Rachel , Loo Joseph A.
Published: January 2020

Top-down proteomics by mass spectrometry (MS) involves the mass measurement of an intact protein followed by subsequent activation of the protein to generate product ions. Electron-based fragmentation methods like electron capture dissociation (ECD) and electron transfer dissociation (ETD) are widely used for these types of analysis, however these fragmentation methods can be inefficient due to the low energy electrons fragmenting the protein without the dissociation products; that is no detection of fragments formed. Recently, electron ionization dissociation (EID), which utilizes higher energy electrons (> 20 eV) has been shown to be more efficient for top-down protein fragmentation compared to other electron-based dissociation methods. Here we demonstrate that the use of EID enhances protein fragmentation and subsequent detection of protein fragments. Protein product ions can form by either single cleavage events, resulting in terminal fragments containing the C-terminus or N-terminus of the protein, or by multiple cleavage events to give rise to internal fragments that do not contain the C-terminus or N-terminus of the protein. Conventionally, internal fragments have been disregarded as reliable assignments of these fragments were limited. Here, we demonstrate that internal fragments generated by EID can account for ~20-40% of the mass spectral signals detected by top-down EID-MS experiments. By including internal fragments, the extent of the protein sequence that can be explained from a single tandem mass spectrum increases from ~50% to ~99% for 29 kDa carbonic anhydrase II and 8.6 kDa ubiquitin. By including internal fragments in the data analysis, previously unassigned peaks can be readily and accurately assigned to enhance the efficiencies of top-down protein sequencing experiments.
Facultative endosymbionts of aphid populations from coastal dunes of the North Sea
Authors: De la Peña Eduardo , Vandomme Viki , Frago Enric
Published: January 2020

Aphids establish symbiotic associations with a diverse assemblage of mutualistic bacteria. Some of them are not required for the host’s survival but still have a crucial impact on the biology and ecology of their host. Facultative symbionts may modify important host-life-history traits and affect the interactions of aphids with other members of the community. So far several species of aphid have been reported to occur in coastal dunes. Given the extreme environmental conditions of this type of habitat and the wide distribution along the European coast of some aphid species, these aphids would be expected to show variation in their facultative endosymbionts. However, there is currently no information available for these species. To address this question, we collected specimens from different populations of aphids (i.e. Schizaphis rufula, Laingia psammae and Rhopalosiphum padi) associated with the dune grass Ammophila arenaria in several locations of the North and the Irish Sea. By means of specific diagnostic PCR’s we checked for the presence of facultative bacterial endosymbionts in these populations. Results of this explorative assessment showed variation in the endosymbiont community according to species and location. All populations sampled along the North Sea coast were associated with the facultative endosymbiont Serratia symbiotica. Hamiltonella defensa was only detected in some specimens coming from the population in Het Zwin, Belgium. Regiella insecticola and the γ-protobacteria X-type were only found associated with the population of Schizaphis rufula in De Panne, Belgium. Although further experiments are necessary to characterize the nature of these symbiotic relationships, our correlation analyses showed a significant co-occurrence of S. symbiotica with H. defensa and R. insecticola with X-type protobacteria suggesting reciprocal regulatory functions. No significant correlation was detected between the number of mummies (i.e. carcasses of aphids parasitized by wasps) and the occurrence of bacterial symbionts. The potential role of these symbionts in coastal dune ecosystems is discussed.
Selective top-down control of epiphytic biomass by amphipods from Posidonia oceanica meadows: implications for ecosystem functioning
Authors: Michel Loïc N. , Dauby Patrick , Dupont Alessandra , Gobert Sylvie
Published: January 2020

Mediterranean Posidonia oceanica meadows shelter an important biomass and biodiversity of amphipod crustaceans that graze on epiphytes. However, their actual significance for ecosystem functional processes is hard to estimate, due to the lack of adequate data. Here, a field microcosm-based inclusion experiment was used to test if three of the dominant taxa of the amphipod community (Apherusa chiereghinii, Dexamine spiniventris and Gammarus spp.) could exert top-down control on seagrass leaf epiphytes. Influence of amphipod activity on nutrient availability for the host species was also investigated. All grazer taxa significantly reduced biomasses of erect macroalgae and erect sessile animals present on leaves. None of them consumed encrusting epiflora or epifauna. This selective top-down control could have important implications for the structure of the epiphytic community on leaves of P. oceanica, which is one of the most diverse and abundant of all seagrass species. Grazing activity of all taxa caused higher N content of seagrass leaves, likely through amphipod excretion and/or sloppy feeding. Since P. oceanica meadows often grow in oligotrophic zones where plant growth can be nutrient-limited, this N enrichment could enhance seagrass production. Overall, the ecological interaction between P. oceanica and amphipods could be seen as a facultative mutualistic relationship. Our results suggest that amphipod mesograzers are key-elements in some of the functional processes regulating these complex and yet endangered ecosystems, which are essential components of Mediterranean coastal zones.
Habitat comparison of Mideopsis orbicularis (O. F. Müller, 1776) and M. crassipes Soar, 1904 (Acari: Hydrachnidia) in the Krąpiel River
Authors: Zawal Andrzej , Śmietana Przemysław , Stępień Edyta , Pešić Vladimir , Kłosowska Magdalena , Michoński Grzegorz , Bańkowska Aleksandra , Dąbkowski Piotr , Stryjecki Robert
Published: January 2020

Ecological studies of water mites have a very long tradition. However, no explicit data have been obtained to date with regard to specific ecological parameters defining autoecological values for particular species, and therefore such values have not been compared between closely related species. The present study is an attempt at making such comparisons between two closely related species: Mideopsis orbicularis and Mideopsis crassipes. Both species are psammophilous; M. orbicularis prefers stagnant waters, while M. crassipes prefers running waters. The research was conducted during 2010 in 89 localities distributed along the Krąpiel River and in water reservoirs found in its valley. The two species were collected solely in the river, where they were found in 26 localities and only these localities were analyzed. Until now M. crassipes was characterized as a species preferring rather fast-flowing habitats, and M. orbicularis as preferring slow water habitats, i.e. isolated still-water bodies. In this study both species preferred slow flow water habitats: 77.5% (225 individuals) of all M. orbicularis specimens and 67.3% (318 individuals) of all M. crassipes specimens were collected in isolated still-water bodies. The only correlations identified between water mite occurrence and water quality were the positive one between the abundance of M. orbicularis and water temperature, the negative one between the abundance of this species and BOD5. There were also some correlations with substrate, including the positive correlation between occurrence of M. crassipes and sandy bottom. M. orbicularis was also encountered on organic bottoms and among water plants.
Long-term changes of breeding success in Montagu’s Harrier Circus pygargus
Authors: Wiącek Jarosław
Published: January 2020

Over a period of almost twenty years, clutch size and breeding success in the Montagu’s Harrier were investigated in the context of changing environmental conditions in the species’ natural breeding habitats in eastern Poland. During the study periods (1990-95 and 2003-12) a decline was noted in the number of breeding pairs in the population nesting on the calcareous peat bogs near Chełm, not far from the Polish-Ukrainian border. Statistically significant differences in breeding parameters between the two periods were also observed. In the first period clutch volumes were greater, as the dimensions of the individual eggs were larger; additionally, more eggs hatched and the hatchling survival rate was higher. Some habitat conditions were different in the two periods, with the water level and height of vegetation near the nests being lower in the second period. The harriers’ food in the two study periods fluctuated strongly with regard to the content of small mammals and compensatory items. In the second period a distinct increase in predator pressure was noted. Pressure from terrestrial predators diminished whereas that from aerial predators increased. Broods in semi-colonies, where birds actively defended their nests, enjoyed a higher rate of survival, as did nests situated far in from the edge of peat bogs. The results suggest that the decline in breeding numbers was driven by increased predation, which was in turn a consequence of habitat changes in the natural environment of eastern Poland.
Complete mitochondrial genome of Whitmania laevis (Annelida, Hirudinea) and comparative analyses within Whitmania mitochondrial genomes
Authors: Ye Fei , Liu Ting , Zhu Wenbo , You Ping
Published: January 2020

The complete mitochondrial genome of Whitmania laevis is 14,442 bp in length and contains 37 genes including 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and two ribosomal RNA (rRNA) genes. The almost-complete mitochondrial genome of Whitmania acranulata, consisting of 13,494 bp, contains 35 genes including 13 PCGs, 20 tRNA genes, and two rRNA genes. COI phylogenetic analyses showed that the samples reported in GenBank and analysed as Hirudo nipponia KC667144, Hirudinaria manillensis KC688268 and Erpobdella octoculata KC688270 are not the named species and they should belong to Whitmania. We compared and analyzed the characteristics of nucleotide composition, codon usage, and secondary structures of 22 tRNAs and two rRNAs from Whitmania taxa. Moreover, we analyzed phylogenetic relationships of Annelida using maximum likelihood (ML) and Bayesian inference (BI) methods, based on 11 mitochondrial genes. Our results reveal that W. laevis has a close relationship with W. pigra.
First records of Myotis alcathoe von Helversen & Heller, 2001 in Belgium
Authors: Nyssen Pierrette , Smits Quentin , Van de Sijpe Marc , Vandendriessche Bob , Halfmaerten Daan , Dekeukeleire Daan
Published: January 2020

This is a Short Note without an abstract.
A first report of introduced non-native damselfly species (Zygoptera, Coenagrionidae) for Belgium
Authors: Adriaens Tim , De Knijf Geert
Published: January 2020

This is a Short Note without an abstract.
Changes in prey importance and prey niche overlap of sexes during the alpine newt breeding season
Authors: Kopecký Oldřich
Published: January 2020

Urodeles, including European newts, are usually sexually dimorphic predators. Among newts, the alpine newt has the most pronounced sexual size dimorphism (in favour of females). Gender is a factor that is often associated with intra-specific diet differences. Despite the significant number of dietary studies on the alpine newt, some topics such as the breadth of the trophic niche and its overlap between sexes, or inter-sexual differences in qualitative and quantitative composition of prey remain unresolved. The present study dealing with these questions was conducted at two localities (ponds at an elevation of about 450 m) in the Czech Republic. Newts were captured from the banks during the entire breeding season using a dip net, and the stomach contents were extracted using a stomach flushing technique. Altogether 190 individuals were sampled, and a total of 1,417 prey items were obtained. The available food sources differed over the course of the breeding season, as newts changed the taxa they preyed on. This reflects the ability of newts to switch between several hunting strategies. The overall food niche overlap between the sexes was relatively large (C = 0.761, resp. C = 0.797). Inter-sexual differences were detected at both localities, mainly in the number of prey items consumed from the most important prey categories such as Rana eggs or Isopoda, which were consumed in higher numbers by females. The findings of this study suggest that females are more sensitive to the trade-off between energy intake and expenditure during the breeding season.