bluuebunny/crossref_metadata_2025 huggingface dataset:
Viktigt att lärare engagerar sig både under och efter grupparbeten
Authors: Westman Anna-Karin
Published: November 2019

När lärare ställer frågor för att få elever att prata med varandra och reflektera över ett ämnesinnehåll så blir inte alltid elevsamtalen så innehållsrika. En ny studie uppmärksammar lärarens viktiga roll för att hjälpa grupper som kört fast. Lärarens roll är också viktig för att lyfta resultaten från grupparbeten i en efterföljande diskussion med hela klassen.
El uso de las TICS en colegios públicos de la ciudad de Loja
Authors: Jaramillo Luzuriaga Silvia Alexandra , Tacuri Peña Lorena del Cisne , Hurtado Cuenca Celso Dario , Muñoz Cabrera Carmen Paulina
Published: November 2019

El siguiente artículo tiene por objetivo analizar la importancia del uso de las técnicas de la información y la comunicación en los colegios públicos de la ciudad de Loja, como estrategia metodológica para mejorar el proceso de enseñanza aprendizaje, puesto que cada vez es más amplia la información que se puede compartir mediante los diferentes soportes tecnológicos. La metodología que se utilizó incluye todo un proceso investigativo enmarcado en los métodos inductivo-deductivo; además para obtener la información empírica sobre el objeto de estudio se aplicó encuestas a los directores de los colegios públicos de la ciudad de Loja. En los resultados obtenidos en la investigación se revelaron que las técnicas de la información y la comunicación se han convertido en una poderosa herramienta para el proceso de enseñanza aprendizaje, ya que es un medio muy utilizado tanto en la educación media como en todos los ámbitos educativos; ello demuestra principalmente que la utilización de las técnicas de comunicación abre la posibilidad de aumentar el nivel de participación, la comunicación y la socialización del conocimiento con el afán de lograr aprendizajes significativos por medio del uso de recursos tecnológicos.
Convivencia y comunicación escolar: Transformación desde la acción y la participación
Authors: Barrios Briceño Nanci Coromoto , Marrero Castro Eli , Gómez Naranjo Maria Eugenia , Quiroz Villacís Jenny Andrea
Published: November 2019

La presente investigación tuvo como propósito Aplicar un Plan de acción dirigido a fortalecer la convivencia y la comunicación en una institución educativa pública en Venezuela a través de la Investigación Acción Participativa. El enfoque metodológico se circunscribió a la perspectiva del Paradigma Crítico promoviendo la participación del colectivo. Se llevó a cabo a través de cuatro fases En la Diagnóstica, se describió el contexto de investigación usando la encuesta como técnica de recolección de datos en su modalidad de cuestionario a estudiantes, docentes, administrativos, obreros y madres, padre representantes. Se realizaron grupos de discusión con los docentes, además de notas de campo y fotografías. El diagnóstico refleja que los estudiantes tienen poco compromiso con sus responsabilidades académicas, falta de cooperación por parte de los padres y representantes e incumplimiento de las normas de convivencia. Realizada la jerarquización de necesidades y aplicada la matriz FODA, resultó dar relevancia a la convivencia escolar debido a su importancia para la comunicación, e integración de los entes del proceso educativo. La fase de la Planificación permitió organizar las estrategias de acción La fase de la ejecución corresponde a la aplicación de las estrategias. En las fases de evaluación y retroalimentación se pudo concluir que cada una de las actividades ejecutadas en el marco del Plan de Acción propuesto generó el compromiso de seguir trabajando en pro de una sociedad capaz y dispuesta a relacionarse respetando la individualidad del otro, desde una comunicación armónica en la convivencia escolar.
Emprendimiento dinámico, crecimiento económico y política pública en el Ecuador
Authors: Campuzano Vásquez John Alexander , Cedillo Chalaco Luis Fernando , Chuquirima Espinoza Samuel Efraín , Romero Black Wilton Eduardo
Published: November 2019

Desde Cantillon 1732 hasta las contribuciones actuales que han realizado distintos economistas para entender el comportamiento e implicaciones de emprender, permiten establecer el objetivo de la actual investigación, la cual trata de explorar la compleja relación existente entre el emprendimiento y el crecimiento económico a partir del impulso que proporcionan las políticas públicas y programas implementados en el Ecuador desde el período 2007 – 2017, siendo el corte temporal más largo con el que ha contado el país con un solo gobierno de línea política denominada socialismo del siglo XXI. Para esta investigación se ha tomado como referencia el reporte del Doing Business del 2018, el Global Entrepreneurship Monitor 2017 y las normas creadas en los últimos diez años en Ecuador que apoyan el emprendimiento. Usando el enfoque metodológico mixto (cuantitativo-cualitativo) y el alcance descriptivo exploratorio transversal y longitudinal, se revisaron y analizaron datos presentados por el Doing Businees 2018 del Banco Mundial y el Global Entrepreneurship Monitor 2017; sumándose a la revisión literaria de diferentes artículos de categoría científica y de las políticas establecidas por el gobierno ecuatoriano del período antes mencionado. Los principales resultados encontrados en torno a Ecuador evidencian la existencia de una relación positiva entre la actividad emprendedora y el crecimiento económico, a tal punto, que se puede observar como las políticas públicas tomadas desde el 2010 han generado un entorno favorable para mejorar el posicionamiento de este país en la forma de hacer negocios rentables.
Percepción y fomento del turismo alternativo en el distrito de Lunahuaná – Cañete, Lima -Perú
Authors: Sandoval Mendoza Jesus Amarildo Leonardo , Nolazco Labajos Fernando Alexis , Salvador García Claribel Rosario
Published: November 2019

El objetivo fue exponer el turismo alternativo en el distrito de Lunahuaná – Cañete, departamento de Lima, Perú. La investigación presenta un sintagma holístico, de enfoque mixto; la muestra estuvo compuesta por cien personas entre pobladores y turistas que visitan el distrito. Para los resultados cuantitativos se diseñó una encuesta aplicada a personas entre los dieciocho y cincuenta años de edad; identificándose con el diagrama de Pareto dos problemas críticos, uno de ellos es la capacidad del distrito para albergar a los turistas en temporadas altas y los guías no poseen conocimientos técnicos. Para el análisis cualitativo se realizaron entrevistas a personas que conocen y trabajan en Lunahuaná; quienes indicaron que los recursos turísticos no están conservados, falta capacitar a los guías de turismo y urge realizar un convenio con la policía de turismo. La propuesta tiene como objetivo mejorar la planta turística durante las temporadas altas, brindar servicios de hospedaje en casas y difundir el valor histórico patrimonial. Además, se debe mejorar la calidad del servicio del guiado y fomentar no solo por el turismo tradicional sino por otras variedades como la gastronomía, el turismo vivencial, místico, cultural; para incrementar la economía y la calidad de vida de los pobladores.
TIC para la inclusión educativa universitaria en la UPS Sede Guayaquil
Authors: Chávez Huacón Kléver Andrés , Naranjo Sánchez Bertha Alice
Published: November 2019

La inclusión educativa universitaria es un tema que ha sido muy poco investigado en nuestro país. Muchas variables inciden en una plena inclusión educativa de estudiantes con discapacidad a nivel superior. El objetivo de este artículo es identificar las TIC que los estudiantes de diferentes carreras de la Universidad Politécnica Salesiana Sede Guayaquil utilizan para favorecer su inclusión, así como el porcentaje de uso de las TIC que ofrece el Centro de Apoyo para la Inclusión de la UPS. A través de la revisión bibliográfica y el análisis documental, entrevistas a personal administrativo, técnico y docente de la universidad, así como de encuestas aplicadas a estudiantes con discapacidad se pudo obtener información relevante sobre las TIC que se utilizan en el proceso de enseñanza aprendizaje inclusivo. Como resultado se obtuvo la identificación de las herramientas TIC que los estudiantes con discapacidad utilizan en su proceso de enseñanza-aprendizaje.
Fingerprints Classification through Image Analysis and Machine Learning Method
Authors: Nguyen Huong Thu , Nguyen Long The
Published: November 2019

The system that automatically identifies the anthropometric fingerprint is one of the systems that interact directly with the user, which every day will be provided with a diverse database. This requires the system to be optimized to handle the process to meet the needs of users such as fast processing time, almost absolute accuracy, no errors in the real process. Therefore, in this paper, we propose the application of machine learning methods to develop fingerprint classification algorithms based on the singularity feature. The goal of the paper is to reduce the number of comparisons in automatic fingerprint recognition systems with large databases. The combination of using computer vision algorithms in the image pre-processing stage increases the calculation time, improves the quality of the input images, making the process of feature extraction highly effective and the classification process fast and accurate. The classification results on 3 datasets with the criteria for Precision, Recall, Accuracy evaluation and ROC analysis of algorithms show that the Random Forest (RF) algorithm has the best accuracy (≥96.75%) on all 3 databases, Support Vector Machine (SVM) has the best results (≥95.5%) 2 / 3 databases.
Greening Modern Rice Farming Using Vermicompost and Its Impact on Productivity and Efficiency: An Empirical Analysis from Bangladesh
Authors: Rahman Sanzidur , Barmon Basanta Kumar
Published: November 2019

Greening modern rice farming while improving productivity and reducing chemical use is a desirable goal for sustainable agriculture. This paper analyzes the impact of vermicomposting on productivity and efficiency of modern rice farming using a random sample of 340 farmers from the southwestern region of Bangladesh by applying a stochastic production frontier approach. Results reveal that productivity is significantly higher and the use of chemicals is significantly lower for vermicompost users as expected. However, profitability gain is not significantly different mainly due to the high cost of vermicompost. Use of vermicompost significantly increases productivity along with other conventional inputs and its users are relatively more technically efficient. Policy implications include investments to raise farmers’ awareness of the benefits of vermicomposting and support entrepreneurs to expand commercial production of vermicompost, which will synergistically curb the use of chemicals in modern rice farming while improving productivity and efficiency.
Effects of Treatment with Electrolyzed Oxidizing Water on Postharvest Diseases of Avocado
Authors: Hassan Md Kamrul , Dann Elizabeth
Published: November 2019

The present study comprised five trials to investigate the efficacy of postharvest treatment with electrolyzed oxidizing (EO) water on postharvest disease development in avocado. Mature (dry matter 24–34%), hard green fruit cv. Hass (four trials), and cv. Wurtz (one trial) from orchards receiving minimal fungicide sprays were sourced, and subsequently dipped for 30 s in treatment solutions. Fruit were ripened at 23 °C and 65% relative humidity to encourage postharvest disease development, and assessed when ripe for anthracnose and stem end rot (SER), arising from natural field infections and/or the size of lesions resulting from post-treatment inoculation with Colletotrichum siamense. In the case of natural infection, EO water treatment reduced severity of SER disease by 30–75% compared with water treated control fruit in all four trials where it was assessed. Reduction in severity of SER after Graduate A+ fungicide or hypochlorite (NaOCl) bleach treatment ranged from 60–88% or 25–50%, respectively, compared with water controls. Under extremely high anthracnose disease pressure, 20% v/v EO water, NaOCl, as well as Graduate A+ fungicide treatments were mostly ineffective. Treatments in the final trial were applied as overhead sprays in an experimental-scale packing line to simulate commercial conditions. This was the only trial where anthracnose (as well as SER) was significantly reduced in fruit by 20% v/v EO water (12–35%) and Graduate A+ (34%) compared with water control. In two trials with C. siamense-inoculated fruit, anthracnose lesion size was reduced by 68–85%, and 90–100% by 20% v/v EO water and Graduate A+, respectively, compared with water-treated fruit. Fruit firmness and the number of days to ripen were mostly not affected by the treatments. This study demonstrates the potential for electrolyzed oxidizing water to be incorporated into integrated management programs for postharvest diseases of avocado, and possibly other fresh produce.
Expression Levels of the γ-Glutamyl Hydrolase I Gene Predict Vitamin B9 Content in Potato Tubers
Authors: Robinson Bruce R. , Garcia Salinas Carolina , Ramos Parra Perla , Bamberg John , Diaz de la Garza Rocio I. , Goyer Aymeric
Published: November 2019

Biofortification of folates in staple crops is an important strategy to help eradicate human folate deficiencies. Folate biofortification using genetic engineering has shown great success in rice grain, tomato fruit, lettuce, and potato tuber. However, consumers’ skepticism, juridical hurdles, and lack of economic model have prevented the widespread adoption of nutritionally-enhanced genetically-engineered (GE) food crops. Meanwhile, little effort has been made to biofortify food crops with folate by breeding. Previously we reported >10-fold variation in folate content in potato genotypes. To facilitate breeding for enhanced folate content, we attempted to identify genes that control folate content in potato tuber. For this, we analyzed the expression of folate biosynthesis and salvage genes in low- and high-folate potato genotypes. First, RNA-Seq analysis showed that, amongst all folate biosynthesis and salvage genes analyzed, only one gene, which encodes γ-glutamyl hydrolase 1 (GGH1), was consistently expressed at higher levels in high- compared to low-folate segregants of a Solanum boliviense Dunal accession. Second, quantitative PCR showed that GGH1 transcript levels were higher in high- compared to low-folate segregants for seven out of eight pairs of folate segregants analyzed. These results suggest that GGH1 gene expression is an indicator of folate content in potato tubers.
Crop Organ Segmentation and Disease Identification Based on Weakly Supervised Deep Neural Network
Authors: Wu Yang , Xu Lihong
Published: November 2019

Object segmentation and classification using the deep convolutional neural network (DCNN) has been widely researched in recent years. On the one hand, DCNN requires large data training sets and precise labeling, which bring about great difficulties in practical application. On the other hand, it consumes a large amount of computing resources, so it is difficult to apply it to low-cost terminal equipment. This paper proposes a method of crop organ segmentation and disease recognition that is based on weakly supervised DCNN and lightweight model. While considering the actual situation in the greenhouse, we adopt a two-step strategy to reduce the interference of complex background. Firstly, we use generic instance segmentation architecture—Mask R-CNN to realize the instance segmentation of tomato organs based on weakly supervised learning, and then the disease recognition of tomato leaves is realized by depth separable multi-scale convolution. Instance segmentation algorithms usually require accurate pixel-level supervised labels, which are difficult to collect, so we propose a weakly supervised instance segmentation assignment to solve this problem. The lightweight model uses multi-scale convolution to expand the network width, which makes the extracted features richer, and depth separable convolution is adopted to reduce model parameters. The experimental results showed that our method reached higher recognition accuracy when compared with other methods, at the same time occupied less memory space, which can realize the real-time recognition of tomato diseases on low-performance terminals, and can be applied to the recognition of crop diseases in other similar application scenarios.
Behavior of Vine Varieties Resistant to Fungal Diseases in the Somontano Region
Authors: Casanova-Gascón José , Ferrer-Martín Carla , Bernad-Eustaquio Antonio , Elbaile-Mur Andrea , Ayuso-Rodríguez José M. , Torres-Sánchez Sergio , Jarne-Casasús Adrián , Martín-Ramos Pablo
Published: November 2019

The vine is highly susceptible to numerous fungal diseases, the incidence and severity of which are increasing because of climate change. To fight them, large amounts of phytosanitary products are generally used, although they entail important economic and environmental costs. The new fungus resistant vine varieties (PIWI) constitute one of the most active lines of research on plant material in viticulture and are regarded as a viable solution to respond to the requirements of European Directive 2009/128/EC. In the present work, the evolution and impact of the three main fungal diseases (powdery mildew, downy mildew and botrytis bunch rot) were monitored in plots in the Somontano region (Huesca, Spain), comparing three PIWI varieties (Sauvignon Kretos, Souvignier gris and Muscaris) with a susceptible control variety (Sauvignon blanc) in real field growing conditions over three successive years (2016–2018). The main ampelographic characters of each variety were studied and a weekly follow-up was carried out to track the development of each disease, relating it to climatic variables. Regardless of the climatic conditions (one of the growing seasons was rainy and the other two corresponded to dry years, with differences in the distribution of rainfall), the three PIWI varieties hardly presented any symptoms, demonstrating a high resistance to downy mildew and powdery mildew and even to botrytis. Principal component analysis results pointed to a differential behavior versus the control and treated Sauvignon blanc plants in terms of disease resistance. Based on production results, despite the youth of the plantation, the excellent potential of Sauvignon Kretos variety was observed. However, from the analysis of the quality of wine obtained in microvinifications from these fungus resistant varieties in the second and third year, the one obtained from Muscaris seemed to have the best organoleptic properties. Apart from environmental considerations, given that these fungus resistant varieties can significantly contribute to the sustainability of wineries, they may also respond to the demand of consumers who want zero-pesticide products or of the supporters of ecological products adjusted to European regulations.
Estimating Canopy Parameters Based on the Stem Position in Apple Trees Using a 2D LiDAR
Authors: Tsoulias Nikos , Paraforos Dimitrios S. , Fountas Spyros , Zude-Sasse Manuela
Published: November 2019

Data of canopy morphology are crucial for cultivation tasks within orchards. In this study, a 2D light detection and range (LiDAR) laser scanner system was mounted on a tractor, tested on a box with known dimensions (1.81 m × 0.6 m × 0.6 m), and applied in an apple orchard to obtain the 3D structural parameters of the trees (n = 224). The analysis of a metal box which considered the height of four sides resulted in a mean absolute error (MAE) of 8.18 mm with a bias (MBE) of 2.75 mm, representing a root mean square error (RMSE) of 1.63% due to gaps in the point cloud and increased incident angle with enhanced distance between laser aperture and the object. A methodology based on a bivariate point density histogram is proposed to estimate the stem position of each tree. The cylindrical boundary was projected around the estimated stem positions to segment each individual tree. Subsequently, height, stem diameter, and volume of the segmented tree point clouds were estimated and compared with manual measurements. The estimated stem position of each tree was defined using a real time kinematic global navigation satellite system, (RTK-GNSS) resulting in an MAE and MBE of 33.7 mm and 36.5 mm, respectively. The coefficient of determination (R2) considering manual measurements and estimated data from the segmented point clouds appeared high with, respectively, R2 and RMSE of 0.87 and 5.71% for height, 0.88 and 2.23% for stem diameter, as well as 0.77 and 4.64% for canopy volume. Since a certain error for the height and volume measured manually can be assumed, the LiDAR approach provides an alternative to manual readings with the advantage of getting tree individual data of the entire orchard.
Three-Dimensional Morphological Measurement Method for a Fruit Tree Canopy Based on Kinect Sensor Self-Calibration
Authors: Yang Haihui , Wang Xiaochan , Sun Guoxiang
Published: November 2019

Perception of the fruit tree canopy is a vital technology for the intelligent control of a modern standardized orchard. Due to the complex three-dimensional (3D) structure of the fruit tree canopy, morphological parameters extracted from two-dimensional (2D) or single-perspective 3D images are not comprehensive enough. Three-dimensional information from different perspectives must be combined in order to perceive the canopy information efficiently and accurately in complex orchard field environment. The algorithms used for the registration and fusion of data from different perspectives and the subsequent extraction of fruit tree canopy related parameters are the keys to the problem. This study proposed a 3D morphological measurement method for a fruit tree canopy based on Kinect sensor self-calibration, including 3D point cloud generation, point cloud registration and canopy information extraction of apple tree canopy. Using 32 apple trees (Yanfu 3 variety) morphological parameters of the height (H), maximum canopy width (W) and canopy thickness (D) were calculated. The accuracy and applicability of this method for extraction of morphological parameters were statistically analyzed. The results showed that, on both sides of the fruit trees, the average relative error (ARE) values of the morphological parameters including the fruit tree height (H), maximum tree width (W) and canopy thickness (D) between the calculated values and measured values were 3.8%, 12.7% and 5.0%, respectively, under the V1 mode; the ARE values under the V2 mode were 3.3%, 9.5% and 4.9%, respectively; and the ARE values under the V1 and V2 merged mode were 2.5%, 3.6% and 3.2%, respectively. The measurement accuracy of the tree width (W) under the double visual angle mode had a significant advantage over that under the single visual angle mode. The 3D point cloud reconstruction method based on Kinect self-calibration proposed in this study has high precision and stable performance, and the auxiliary calibration objects are readily portable and easy to install. It can be applied to different experimental scenes to extract 3D information of fruit tree canopies and has important implications to achieve the intelligent control of standardized orchards.
Greenhouse Gas Emissions in Dairy Goat Farming Systems: Abatement Potential and Cost
Authors: Sintori Alexandra , Tzouramani Irene , Liontakis Angelos
Published: November 2019

Dairy goat farming is an important agricultural activity in the Mediterranean region. In Greece the activity offers occupation and income to thousands of families mainly located in mountainous and semi-mountainous areas of the country where it utilizes low productivity pastures and shrub lands. Furthermore, goats are more resilient to climate changes compared to other species, and are often characterized as ideal for keeping in drought areas. However, there is still limited evidence on total greenhouse gases (GHG) emitted from goat farms and their mitigation potential. In this context, this study aims to estimate GHG emissions of goat farms in Greece and explore their abatement options using an economic optimization model. Three case studies are explored i.e., an extensive, a semi-intensive and an intensive goat farm that correspond to the main goat production systems identified in Greece. The analysis aims to assess total GHGs as well as the impact of abatement on the structures, gross margins and labor inputs of the farms under investigation. The issue of the marginal abatement cost is also addressed. The results indicate that the extensive farm causes higher emissions/kg of milk produced (4.08 kg CO2-eq) compared to the semi-intensive and intensive farms (2.04 kg and 1.82 kg of CO2-equivelants, respectively). The results also emphasize the higher marginal abatement cost of the intensive farm. In all farm types, abatement is achieved primarily through the reduction of the livestock capital and secondarily by other appropriate farming practices, like substitution of purchased feed with homegrown feed.
Growth Performance and Carcass Traits Responses to Dried Distillers’ Grain with Solubles Feeding of Growing Awassi Ram Lambs
Authors: Hatamleh Safa’ M. , Obeidat Belal S.
Published: November 2019

This study considers the impact of dried distillers’ grain with solubles (DDGS) in diets of lambs. Randomly; 27 lambs were distributed to one of three diets. Diets were: a control diet (CON; n = 9), a 125 (DDGS125; n = 9) or a 250 g/kg DDGS (DDGS250; n = 9) of dietary dry matter (DM). The lambs were fed using these diets for 91 days. To assess carcass traits; five lambs were randomly selected at the end of the study. No significant differences were detected in intake and digestibility of DM; crude protein and fiber. Average daily gain did not differ among diets. Carcass characteristics did not differ among diets. With the exception of shear force and redness, which were greater in DDGS250 than in DDGS125 and CON diets, meat quality parameters were unaffected. Eye muscle area decreased in DDGS125 than in DDGS250 and CON diet. These results demonstrate that the feeding of lambs on DDGS at 125 or 250 g/kg DM did not have any impact on growth. These diets only had a simple effect on the characteristics of carcass and meat quality. These results suggest that it would be suitable to introduce these feeds into sheep nutrition in the future.
Effects on Intestinal Mucosal Morphology, Productive Parameters and Microbiota Composition after Supplementation with Fermented Defatted Alperujo (FDA) in Laying Hens
Authors: Rebollada-Merino Agustín , Bárcena Carmen , Ugarte-Ruiz María , Porras Néstor , Mayoral-Alegre Francisco J. , Tomé-Sánchez Irene , Domínguez Lucas , Rodríguez-Bertos Antonio
Published: November 2019

The olive oil sector is currently adapting its traditional function to also become a supplier of high-value by-products that possess antioxidant, anti-inflammatory and antimicrobial properties. In this study, we evaluated the effect of the fermented defatted alperujo (FDA) on the intestinal health of laying hens. The morphology of the duodenal and cecal mucosa, the composition of the intestinal microbiota and the productivity of a batch of laying hens were evaluated after FDA supplementation. At early life stages, significant differences (p < 0.001) were observed in duodenal villi height and in crypt depth of both the duodenum and the cecum in the FDA-supplemented group, indicating improved intestinal health in this group. Microbiota composition in the hatchery group supplemented with FDA had a higher abundance of Actinobacteria, Firmicutes and Proteobacteria, and higher bacterial diversity. During the production period, significant differences (p < 0.05) were observed in the number of broken eggs from the supplemented group. We conclude that FDA supplementation improves the absorption capacity of the intestinal mucosa and modifies the intestinal microbiota to favor a greater immune response, leading to an increase in egg production.
Definitive Cefazolin Treatment for Community-Onset Enterobacteriaceae Bacteremia Based on the Contemporary CLSI Breakpoint: Clinical Experience of a Medical Center in Southern Taiwan
Authors: Lee Ching-Chi , Lee Chung-Hsun , Chen Po-Lin , Hsieh Chih-Chia , Tang Hung-Jen , Ko Wen-Chien
Published: November 2019

Cefazolin is traditionally active against Escherichia coli, Klebsiella species, and Proteus mirabilis (EKP) isolates. The Clinical and Laboratory Standards Institute (CLSI) has twice updated cefazolin susceptibility breakpoints for EKP since 2010, but its role in the definitive treatment of cefazolin-susceptible EKP bacteremia remains debated. To assess its efficacy as a definitive agent, the 8-year cohort study consisted of 941 adults with monomicrobial cefazolin-susceptible EKP bacteremia, based on the CLSI criteria issued in 2019, was retrospectively established in a medical center. Based on the definitive antimicrobial prescription, eligible patients were categorized into the cefazolin (399 patients, 42.4%) and broader-spectrum antibiotic (BSA) (542, 57.6%) groups. Initially, fewer proportions of patients with fatal comorbidities (the McCabe classification) and the critical illness (a Pitt bacteremia score ≥4) at the onset and day 3 of the bacteremia episode were found in the cefazolin group, compared to the BSA group. After propensity-score matching, no significant difference of patient proportions between the cefazolin (345 patients) and BSA (345) groups was observed, in terms of the elderly, types and severity of comorbidities, bacteremia severity at the onset and day 3, major bacteremia sources, and the 15-day and 30-day crude mortality. In early outcomes, lengths of time to defervescence, intravenous (IV) antimicrobial administration, and hospitalization were similar in the two matched groups; lower costs of IV antimicrobial administration were observed in the cefazolin group. Notably, for late outcomes, lower proportions of post-treatment infections caused by antimicrobial-resistant pathogens (ARPs) and post-treatment mortality rates were evidenced in the cefazolin group. Conclusively, cefazolin is definitively efficacious and cost-effective for adults with community-onset cefazolin-susceptible EKP bacteremia in this one-center study, compared to BSAs. However, a prospective multicenter study should be conducted for external validation with other communities.
Recent Progress in the Development of Small-Molecule FtsZ Inhibitors as Chemical Tools for the Development of Novel Antibiotics
Authors: Carro Laura
Published: November 2019

Antibiotics are potent pharmacological weapons against bacterial pathogens, nevertheless their efficacy is becoming compromised due to the worldwide emergence and spread of multidrug-resistant bacteria or “superbugs”. Antibiotic resistance is rising to such dangerous levels that the treatment of bacterial infections is becoming a clinical challenge. Therefore, urgent action is needed to develop new generations of antibiotics that will help tackle this increasing and serious public health problem. Due to its essential role in bacterial cell division, the tubulin-like protein FtsZ has emerged as a promising target for the development of novel antibiotics with new mechanisms of action. This review highlights the medicinal chemistry efforts towards the identification of small-molecule FtsZ inhibitors with antibacterial activity in the last three years.
Hibiscus Acid and Chromatographic Fractions from Hibiscus Sabdariffa Calyces: Antimicrobial Activity against Multidrug-Resistant Pathogenic Bacteria
Authors: Portillo-Torres Lizbeth Anahí , Bernardino-Nicanor Aurea , Gómez-Aldapa Carlos Alberto , González-Montiel Simplicio , Rangel-Vargas Esmeralda , Villagómez-Ibarra José Roberto , González-Cruz Leopoldo , Cortés-López Humberto , Castro-Rosas Javier
Published: November 2019

The anti-microbial properties of acetone extracts from Hibiscus sabdariffa calyces, fractions isolated by silica gel chromatography and hibiscus acid purified from some of these fractions and additionally identified by nuclear magnetic resonance spectroscopy, mid-infrared spectroscopy and X-ray diffraction, were studied against both multidrug-resistant Salmonella strains and pathogenic Escherichia coli bacteria. Gel diffusion was used to determine the anti-microbial effects. The mode of action of hibiscus acid was determined by crystal violet assay. Hibiscus acid and 17 of the 25 chromatographic fractions obtained, displayed an anti-microbial effect against all bacterial strains tested. Hibiscus acid showed a greater anti-microbial effect than the acetone extract against most of the bacteria strains, while chromatographic fractions IX–XIV exerted the greatest anti-microbial effect against all bacteria. The minimum inhibitory concentration of the acetone extract was 7 mg/mL, and the minimum bactericidal concentration was 10 mg/mL, while the corresponding values for hibiscus acid were 4–7 and 7 mg/mL, respectively. The results of the crystal violet assay indicate that hibiscus acid alters membrane permeability. Hibiscus acid is a potential alternative to control multidrug-resistant bacteria. Due to its ready availability and easy extraction from H. sabdariffa, hibiscus acid is potentially useful in the food industries.
Impact of ApoE Polymorphism and Physical Activity on Plasma Antioxidant Capability and Erythrocyte Membranes
Authors: Piccarducci Rebecca , Daniele Simona , Fusi Jonathan , Chico Lucia , Baldacci Filippo , Siciliano Gabriele , Bonuccelli Ubaldo , Franzoni Ferdinando , Martini Claudia
Published: November 2019

The allele epsilon 4 (ε4) of apolipoprotein E (ApoE) is the strongest genetic risk factor for Alzheimer’s disease (AD). ApoE protein plays a pivotal role in the synthesis and metabolism of amyloid beta (Aβ), the major component of the extracellular plaques that constitute AD pathological hallmarks. Regular exercise is an important preventive/therapeutic tool in aging and AD. Nevertheless, the impact of physical exercise on the well-being of erythrocytes, a good model of oxidative stress and neurodegenerative processes, remains to be investigated, particularly depending on ApoE polymorphism. Herein, we evaluate the oxidative status, Aβ levels, and the membrane’s composition of erythrocytes in a cohort of human subjects. In our hands, the plasma antioxidant capability (AOC), erythrocytes membrane fluidity, and the amount of phosphatidylcholine (PC) were demonstrated to be significantly decreased in the ApoE ε4 genotype and non-active subjects. In contrast, erythrocyte Aβ content and lipid peroxidation increased in ε4 carriers. Regular physical exercise was associated with an increased plasma AOC and membrane fluidity, as well as to a reduced amount of erythrocytes Aβ. Altogether, these data highlight the influence of the ApoE genotype on erythrocytes’ well-being and confirm the positive impact of regular physical exercise.
Specific Activity of Superoxide Dismutase in Stallion Seminal Plasma Is Related to Sperm Cryotolerance
Authors: Papas Marion , Catalán Jaime , Fernandez-Fuertes Beatriz , Arroyo Laura , Bassols Anna , Miró Jordi , Yeste Marc
Published: November 2019

While the removal of seminal plasma is a routine practice prior to equine sperm cryopreservation, this fluid contains the main source of antioxidant enzymes able to scavenge these reactive oxygen species. Therefore, stallion seminal plasma components may have an impact on ejaculate freezability. Against this background, this study was designed to investigate whether the activities of the main stallion seminal plasma antioxidant enzymes are related to sperm cryotolerance. With this purpose, 16 ejaculates were collected from 14 healthy stallions, and each ejaculate was split into two aliquots. The first one was used to evaluate the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GSR) in seminal plasma. The second aliquot was extended and then processed for cryopreservation. Sperm motility and viability were evaluated before and after cryopreservation, and ejaculates were classified as of good (GFE) or poor freezability (PFE) based on total motile and viable spermatozoa at post-thaw. We observed that, while the specific activities of CAT, GPX, and GSR were similar between GFE and PFE, that of SOD was significantly (p < 0.05) higher in GFE than in PFE. We can thus conclude that, in stallions, the specific activity of SOD in the seminal plasma of a given ejaculate might be related to its freezability.
Phytochemical Characterization of Commercial Processed Blueberry, Blackberry, Blackcurrant, Cranberry, and Raspberry and Their Antioxidant Activity
Authors: Diaconeasa Zoriţa , Iuhas Cristian I. , Ayvaz Huseyin , Rugină Dumitriţa , Stanilă Andreea , Dulf Francisc , Bunea Andrea , Socaci Sonia Ancuța , Socaciu Carmen , Pintea Adela
Published: November 2019

Being delicious and containing strong disease-fighting agents, berries represent an increasing proportion of fruits consumed nowadays in our diet. However, berries are highly perishable as fresh and, therefore, they are usually processed into various products to extend their shelf-life and availability throughout the year. Among the fruit-containing products, jam is one of the most common due to its nourishing properties, its low production costs, and its accessibility for a lengthy period. Rather than home preparation, consumers nowadays increasingly prefer to purchase commercial jams from markets due to its convenience. Although fresh berries have been extensively studied for their phenolic compounds, a limited number of studies investigating commercially manufactured jams have been conducted so far. Considering this, the objective of this study was to assess the total phenolic, flavonoid, and anthocyanin content and the antioxidant activity of five commonly consumed commercial berry jams (blueberry (Vaccinium myrtillus), blackberry (Rubus fruticosus) and blackcurrant (Ribes nigrun) mixture, blackcurrant (Ribes nigrun), cranberry (Vaccinium macrocarpon) and raspberry (Rubus idaeus)) collected from the market. Even though a possible loss of phenolics, anthocyanins, and a decrease of radical scavenging activity may occur during jam processing and subsequent storage, our data indicated that the selected commercial jams remained good sources of nutritive molecules with antioxidant properties based on the high levels of total phenolics, flavonoids, anthocyanins, and elevated antioxidant activities determined in this study. Additionally, the samples were characterized by GC-MS for their volatile profiles, and terpenes were found to be the dominating class covering more than 74% of volatile compounds in the jams.
Heterogeneous Image Matching via a Novel Feature Describing Model
Authors: Zhou Bin , Duan Xuemei , Ye Dongjun , Wei Wei , Woźniak Marcin , Damaševičius Robertas
Published: November 2019

Computer vision has been developed greatly in the past several years, and many useful and interesting technologies have been presented and widely applied. Image matching is an important technology based on similarity measurement. In this paper, we propose a novel feature describing model based on scale space and local principle component analysis for heterogeneous image matching. The traditional uniform eight-direction statistics is updated by a task-related k-direction statistics based on prior information of the keypoints. In addition, the k directions are determined by an approximately solution of a Min-Max problem. The principle component analysis is introduced to compute the main directions of local patches based on the gradient field. In addition, the describing vector is formed by then implementing PCA on each sub-patch of a 4 × 4 mesh. Experimental results show the accuracy and efficiency of proposed method.
The Microalgae Biorefinery: A Perspective on the Current Status and Future Opportunities Using Genetic Modification
Authors: Schiano di Visconte Gino , Spicer Andrew , Chuck Christopher J. , Allen Michael J.
Published: November 2019

There is clear scientific evidence that emissions of greenhouse gases (GHG), arising from fossil fuel combustion and land-use change as a result of human activities, are perturbing the Earth’s climate. Microalgae-derived biofuels have been chased since the 1980s without success but, lately, a new biorefinery concept is receiving increasing attention. Here, we discuss the possible solutions to the many problems that make this process unrealised to date, considering also the possibility of including genetically modified (GM) organisms to improve the productivity and process economics. Currently, unless coupled to a service or higher value product production, biofuels derived from microalgae fail to achieve economic reality. However, provided sufficient development of new technologies, potentially including new or improved organisms to lower both production and processing costs, as well as looking at the utility of distributed versus centralised production models, algae biofuels could achieve an impact, off-setting our heavy reliance on petroleum-based liquid fuels.
Micro-Mechanism of Spherical Gypsum Particle Breakage under Ball–Plane Contact Condition
Authors: Yu Shicai , Jia Mincai , Zhou Jian , Zhao Cheng , Li Lin
Published: November 2019

Coarse-grained soils are used extensively in engineering applications. The breakage of coarse-grained soil particles may have a great effect on their mechanical characteristics. It is important to fully understand the phenomenon of particle breakage and comprehend its effect on engineering properties. The aim of this study was to investigate the process and mechanism of spherical particle breakage under ball–plane contact conditions. Particle contact tests and corresponding simulations based on the discrete element method were performed. The mechanical properties and breaking morphologies of gypsum balls, as well as the significant feature of the existence of a cone core under the contact point, were obtained by the experiments. To enable particle crushing in a numerical simulation, noncrushable elementary particles were bonded together to represent the specimen. The numerical model, which was validated by the unconfined compression test and splitting test, was well fitted with the experiment by applying flat-joint contact. More importantly, the combination of the simulation and experiment demonstrated the role that the cone core plays during particle breakage and revealed the mechanism of the formation of the cone core and its effect on particle breakage.
Aerodynamic Performance of Hex-Rotor UAV Considering the Horizontal Airflow
Authors: Lei Yao , Cheng Mingxin
Published: November 2019

In this paper, the aerodynamic performance of a Hex-rotor unmanned aerial vehicle (UAV) with different rotational speeds (1500–2300 RPM) considering the horizontal airflow conditions is analyzed by both simulations and experiments. A low-speed wind tunnel experiments platform is applied to measure the thrust, torque, and power consumption of a Hex-rotor UAV with different rotational speeds in horizontal airflow, which varied from 0 m/s–4 m/s. First, this paper introduces the effect of horizontal airflow on a UAV. Then, the low-speed wind tunnel experiments were carried out on a Hex-rotor UAV (D/L = 0.56) with different horizontal velocities to determine the hover performance. Finally, numerical simulations were obtained with the streamline distributions, pressure distributions, velocity contour, and vortex distributions at different horizontal airflow conditions to describe the aerodynamic interference effect of different horizontal airflows. Combined with the experimental results and numerical simulations results, the horizontal airflow proved to have a significant influence on the aerodynamic performance of the Hex-rotor UAV with an increase in thrust and power. Indeed, the streamlines in the flow field were coupled to each other at the presence of the incoming airflow. Especially when the incoming airflow was larger, the Hex-rotor UAV could properly use low-speed flight to maintain high power loading. Finally, it is inferred that the aerodynamic performance of the Hex-rotor UAV is also related to the movement and deformation of the vortex at the tip of the rotor.
Enhancing Decision Making through Combined Classification Techniques and Probabilistic Data Analysis for Ubiquitous Healthcare Anomaly Monitoring
Authors: Chefira Reda , Rakrak Said
Published: November 2019

A multi-agent data-analytics-based approach to ubiquitous healthcare monitoring is presented in this paper. The proposed architecture gathers a patient’s vital data using wireless body area networks, and the transmitted information is separated into binary component parts and divided into related dataset categories using several classification techniques. A probabilistic procedure is then used that applies a normal (Gaussian) distribution to the analysis of new medical entries in order to assess the gravity of the anomalies detected. Finally, a data examination is carried out to gain insight. The results of the model and simulation show that the proposed architecture is highly efficient in applying smart technologies to a healthcare system, as an example of a research direction involving the Internet of Things, and offers a data platform that can be used for both medical decision making and the patient’s wellbeing and satisfaction with their medical treatment.
X-ray Spectroscopies of High Energy Density Matter Created with X-ray Free Electron Lasers
Authors: Cho Byoung Ick
Published: November 2019

The recent progress in the development of X-ray free electron lasers (XFELs) allows for the delivery of over 1011 high-energy photons to solid-density samples in a femtosecond time scale. The corresponding peak brightness of XFEL induces a nonlinear response of matter in a short-wavelength regime. The absorption of an XFEL pulse in a solid also results in the creation of high energy density (HED) matter. The electronic structure and related fundamental properties of such HED matter can be investigated with the control of XFEL and various X-ray spectroscopic techniques. These experimental data provide unique opportunities to benchmark theories and models for extreme conditions and to guide further advances. In this article, the current progress in spectroscopic studies on intense XFEL–matter interactions and HED matter are reviewed, and future research opportunities are discussed.
Formation and Breakup of an Immiscible Compound Jet with Density or Viscosity Stratification
Authors: Bhagat Kunal D. , Vu Truong V. , Wells John C.
Published: November 2019

Formation of compound drops by breakup of an axisymmetric compound jet injected from a coaxial nozzle into another immiscible coflowing fluid, at various density and viscosity ratios, is numerically investigated. The fluids are assumed to be Newtonian and incompressible and gravity is neglected for simplicity. A Finite Difference Method with Front Tracking is used to track the evolution and breakup of the compound jet. The outcomes of our numerical results show how density and viscosity ratios affect the compound jet’s transition from dripping to jetting mode. The density ratios of inner-to-outer and intermediate-to-outer fluids affect compound jet breakup length, drop diameter and drop formation time more than comparable viscosity ratios. At high density and viscosity ratios, due to high inertia and viscous force respectively, the drop formation is more chaotic and mostly multi-core drops are formed.