bluuebunny/crossref_metadata_2025 huggingface dataset:
Aprovechamiento racional de los recursos naturales y culturales para el turismo comunitario, cantón Montalvo-Los Ríos
Authors: Rivera García Christian , Izurieta Puente Maricela , Cuadro Saucedo Arely
Published: July 2019

El desarrollo local se sustenta en iniciativas turísticas de sostenibilidad rural. La dinámica territorial de las comunidades indígenas, atomizan las múltiples posibilidades de formar clústeres de apoyo a iniciativas de emprendimiento que están acordonadas a planificaciones previamente establecidas en diferentes ramales de organización local, regional, nacional e internacional. Intensificar el rescate y creación de actividades recreativas y de descanso es el reto de la nueva página del Ecuador multiétnico y biodiverso. Estos esfuerzos motivan el acoplamiento de iniciativas turísticas como integrar costumbres, tradiciones y saberes ancestrales para potenciar el turismo comunitario, que aglomeran ideas de jóvenes emprendedores que multiplican sus ideas buscando innovar en mercados cada vez más competitivos. Estos emprendimientos tienen que enfrentar retos mucho más diferenciadores, pérdidas humanas particularmente por el hambre y enfermedades, esto ha comprometido realizar planificaciones que brinden desahogo de estima y control humano sobre la coraza de impunidad en sectores realmente que necesitan ayuda de transformación y apoyo a iniciativas de gran importancia. Se tiene que recordar que el turismo no es la solución a ciertos contratiempos poblacionales, pero si es una gran ayuda para direccionar posibles soluciones de acuerdo a interés social de regeneración turística en ventaja de conservación natural y cultural con máximas oportunidades de desarrollo local. La demanda turística responde a tendencias globalizadoras que diagnóstica, diseña, ejecuta y valora iniciativas productivas de gran calado, proporcionando reorganizar actividades para el disfrute y distracción de los viajeros.
Evaluación del rendimiento de la modulación Binary Offset Carrier (BOC) versus la señal Civil GPS/L1
Authors: Llerena Pintag Andrea Magali , Zabala Haro Mónica Andrea , Pacheco Cunduri Mayra Alejandra , Casignia Vasconez Byron Andres , Oñate Andino Mayra Alejandra
Published: July 2019

En este artículo se realiza una comparación de   evaluación del rendimiento de las técnicas de modulación de señales satelitales de GPS L1, Binary Offset Carrier (BOC) vs. Binary Phase Shift Keying (BPSK). Se realiza un análisis del estado del arte del sistema de posicionamiento GPS desde su lanzamiento hasta la actualidad.  El desarrollo de la simulación se realiza utilizando el software matemático Matlab y se analizaron parámetros para la generación y acondicionamiento de la señal satelital civil de GPS L1, para ser codificada mediante el codificador convolucional (2, 1, 3) y modulada con BOC antes de ser enviada al canal de transmisión. En la etapa de trasmisión se analizaron dos canales de desvanecimiento tipo Rayleigh y Rician. En su etapa de resultados se detallan los gráficos y tablas de los datos obtenidos por la simulación para evaluar el rendimiento del canal en función de los parámetros BER y SNR.
Herramientas de contabilidad gerencial para la toma de decisiones financieras en la empresa Tapitex M&B Cía. Ltda. de la ciudad de Cuenca
Authors: Balcázar Sarmiento Bibiana Maribel , Narváez Zurita Cecilia Ivonne , Erazo Álvarez Juan Carlos
Published: July 2019

La globalización de la economía impone a las pequeñas y medianas empresas condiciones cada vez más hostiles para desafiar la creciente competitividad que prima en la mayoría de industrias. En respuesta a este escenario, los gerentes están forzados a plantear estrategias que les permitan conservar o incrementar su posición en el mercado. Por ende, las empresas deben optar, entre otras formas, por competir a través de un enfoque de identificación de variables clave y liderazgo en costos, para con ello, incrementar sus márgenes de utilidad y elevar sus niveles de competitividad.

Lo antes expuesto, marca una pauta en donde los gerentes tienen la posibilidad de apoyarse en instrumentos y técnicas que les permitan utilizar la información contable como herramientas estratégicas de gestión. En el caso particular de las PYMES ecuatorianas, este es un factor de trascendencia fundamental; por lo que, se considera necesario investigar todas las variables que pueden resultar claves para las empresas, en cuanto al contexto de sus actividades, para posterior a ello, diseñar, implementar y monitorear los indicadores financieros y no financieros a través del cuadro de mando confeccionado sobre la base de la contabilidad gerencial. En este sentido, la presente investigación tiene por finalidad proveer de un portafolio herramental que propicie la participación del contador de la empresa Tapitex Cía. Ltda en la toma de decisiones financieras con base en el análisis de los estados financieros y en la elaboración de un cuadro de mando integral.
Changes in the Soil Microbial Hydrolytic Activity and the Content of Organic Carbon and Total Nitrogen by Growing Spring Barley Undersown with Red Clover in Different Farming Systems
Authors: Kuht Jaan , Eremeev Viacheslav , Talgre Liina , Alaru Maarika , Loit Evelin , Mäeorg Erkki , Esmaeilzadeh-Salestani Keyvan , Luik Anne
Published: July 2019

The experiments were carried out during 2012–2017. There were 5 crops in rotation: Red clover, winter wheat, pea, potato and barley undersown (us) with red clover. There were 5 cropping systems in the experimental setup: 2 conventional systems with chemical plant protection and mineral fertilizers; 3 organic systems which included winter cover crops and farm manure. The aim of the present research was to study the effect of cultivating barley undersown with red clover and the preceding winter cover crop on the soil microbial hydrolytic activity, the change in the content of soil organic carbon (SOC) and total nitrogen (Ntot) compared to the same parameters from the field that was previously under potato cultivation (forecrop of barley in the rotation). The cultivation of barley with red clover (barley (us)) had a positive impact on the soil micro-organisms activity. In organic systems the soil microbial hydrolytic activity increased on average by 19.0%, compared to the conventional systems. By cultivating barley (us) the soil microbial hydrolytic activity had a significant effect on the SOC content only in organic systems where winter cover crops were used. Organic cultivation systems had positive impact on the soil nitrogen content; Ntot in samples taken before sowing the barley (us) was higher by 17.4% and after the cultivation of barley (us) by 14.4% compared to conventional systems, as an average of experimental years. After cultivation of barley (us) with red clover the soil microbial hydrolytic activity had no effect on the soil Ntot content in either cultivation systems.
Assessment of Potential Land Suitability for Tea (Camellia sinensis (L.) O. Kuntze) in Sri Lanka Using a GIS-Based Multi-Criteria Approach
Authors: Layomi Jayasinghe Sadeeka , Kumar Lalit , Sandamali Janaki
Published: July 2019

The potential land suitability assessment for tea is a crucial step in determining the environmental limits of sustainable tea production. The aim of this study was to assess land suitability to determine suitable agricultural land for tea crops in Sri Lanka. Climatic, topographical and soil factors assumed to influence land use were assembled and the weights of their respective contributions to land suitability for tea were assessed using the Analytical Hierarchical Process (AHP) and the Decision-Making Trail and Evaluation Laboratory (DEMATEL) model. Subsequently, all the factors were integrated to generate the potential land suitability map. The results showed that the largest part of the land in Sri Lanka was occupied by low suitability class (42.1%) and 28.5% registered an unsuitable land cover. Furthermore, 12.4% was moderately suitable, 13.9% was highly suitable and 2.5% was very highly suitable for tea cultivation. The highest proportion of “very highly suitable” areas were recorded in the Nuwara Eliya District, which accounted for 29.50% of the highest category. The model validation results showed that 92.46% of the combined “highly suitable” and “very highly suitable” modelled classes are actual current tea-growing areas, showing the overall robustness of this model and the weightings applied. This result is significant in that it provides effective approaches to enhance land-use efficiency and better management of tea production.
The Potential Role of Citrus limon Powder as a Natural Feed Supplement to Boost the Productive Performance, Antioxidant Status, and Blood Biochemistry of Growing Rabbits
Authors: Elwan Hamada A. M. , Dawood Dawood Hosni , Abd El-Aziz El-Shafei Sally Mohamed , Abd El-Mohsen Abd El-Rahman Atef , Abdel-Latif Shaker A. , Mohany Mohamed , Alqahtani Faleh , Alqahtani Saeed , Al-Rejaie Salim S.
Published: July 2019

The current study examined the influence of Citrus limon (dry lemon) on the hemato-biochemical profiles, and antioxidant indices of growing rabbits. Forty-eight growing New Zealand White rabbits (age, eight weeks; weight, 1543.33 ± 25 g) were allocated into three groups (16 animals each), the first group was (control) fed a basal diet, whereas the second and third groups were supplemented with dried lemon, 1% or 2% DLP, respectively. A GC-MS analysis of more than 27 active constituents was performed. Feed conversion efficiency was (p < 0.05) better with diets containing 1% or 2% dry lemon, compared to the control group. Hematological indexes were increased significantly with the addition of DLP compared to those in the control group. Adding 1% or 2% dry lemon to rabbit diet increased (p < 0.05) enzymatic and non-enzymatic antioxidant activities (TAC, SOD, GSH, GST, and CAT) in serum and liver tissues. Taken together, these data reveal the advantages and antioxidant effects of dry lemon supplementation for growing rabbits once supplemented at a maximum of 2% in their daily diet.
Structure–Antioxidant–Antiproliferative Activity Relationships of Natural C7 and C7–C8 Hydroxylated Flavones and Flavanones
Authors: Sordon Sandra , Popłoński Jarosław , Milczarek Magdalena , Stachowicz Martyna , Tronina Tomasz , Kucharska Alicja Z. , Wietrzyk Joanna , Huszcza Ewa
Published: July 2019

Common food flavonoids: chrysin, apigenin, luteolin, diosmetin, pinocembrin, naringenin, eriodictyol, hesperetin, and their analogues with an additional hydroxyl group at the C-8 position obtained via biotransformation were tested for antioxidant activity using the ABTS, DPPH, and ferric ion reducing antioxidant power (FRAP) methods. They were also tested for antiproliferative activity against selected human cancer cell lines—MV-4-11 (biphenotypic B myelomonocytic leukemia), MCF7 (breast carcinoma), LoVo (colon cancer), LoVo/DX (colon cancer doxorubicin resistant), and DU 145 (prostate cancer)—and two normal human cell lines—MCF 10A (breast cells) and HLMEC (lung microvascular endothelial cells). Flavonoids with a C7–C8 catechol moiety indicated much higher antioxidant activity compared with the C7 hydroxy analogues. However, because they were unstable under the assay conditions, they did not show antiproliferative activity or it was very low.
Fault Diagnosis of Rolling Bearing Based on Multiscale Intrinsic Mode Function Permutation Entropy and a Stacked Sparse Denoising Autoencoder
Authors: Dai Juying , Tang Jian , Shao Faming , Huang Shuzhan , Wang Yangyang
Published: July 2019

Effective intelligent fault diagnosis of bearings is important for improving safety and reliability of machine. Benefiting from the training advantages, deep learning method can automatically and adaptively learn more abstract and high-level features without much priori knowledge. To realize representative features mining and automatic recognition of bearing health condition, a diagnostic model of stacked sparse denoising autoencoder (SSDAE) which combines sparse autoencoder (SAE) and denoising autoencoder (DAE) is proposed in this paper. The sparse criterion in SAE, corrupting operation in DAE and reasonable designing of the stack order of autoencoders help to mine essential information of the input and improve fault pattern classification robustness. In order to provide better input features for the constructed network, the raw non-stationary and nonlinear vibration signals are processed with ensemble empirical mode decomposition (EEMD) and multiscale permutation entropy (MPE). MPE features which are extracted based on both the selected characteristic frequency-related intrinsic mode function components (IMFs) and the raw signal, are used as low-level feature for the input of the proposed diagnostic model for health condition recognition and classification. Two experiments based on the Case Western Reserve University (CWRU) dataset and the measurement dataset from laboratory were conducted, and results demonstrate the effectiveness of the proposed method and highlight its excellent performance relative to existing methods.
The Effects of Asphalt Migration on the Dynamic Modulus of Asphalt Mixture
Authors: Wang Hui , Zhan Shihao , Liu Guojun
Published: July 2019

Asphalt migration is one of the significant detrimental effects on asphalt pavement performance. In order to simulate the state after the occurrence of asphalt migration amid asphalt pavement layers and further investigate the effects of asphalt migration on the dynamic modulus of asphalt mixture, samples with different asphalt contents layers were firstly separated into the upper and lower half portions and then compacted together. By conducting the dynamic modulus test with the Superpave Simple Performance Tester (SPT), the variation laws of the dynamic modulus (|E*|) and the phase angle (δ) at different testing temperatures and loading frequencies were analyzed in this paper. Further, the dynamic modulus and the stiffness parameter (|E*|/sinδ) at the loading frequency of 10 Hz and testing temperature of 50 °C were illustrated. Simultaneously, the master curves of the dynamic modulus and phase angle of asphalt mixtures under different testing conditions were constructed to better investigate the effects of asphalt migration on the dynamic modulus by means of Williams–Landel–Ferry (WLF) equation and Sigmoidal function. Results show that, after the asphalt migration, the dynamic modulus of asphalt mixtures increase with the increasing loading frequency while they decrease with the increasing testing temperature; the dynamic modulus and the stiffness parameter are the highest when asphalt mixtures have the optimum asphalt content layers, and then decrease with the incremental difference of asphalt content in the upper and lower half portions. Besides this, different from the master curves of dynamic modulus, the master curves of phase angle firstly increase with the increase of loading frequency to the highest point and then decrease with the further increase of loading frequency and are not as smooth as that of dynamic modulus. It can be concluded that the asphalt migration has compromised the mixture’s mechanical structure, and the more asphalt migrates, the weaker the mechanical properties of asphalt mixture will be. Additionally, based on the shift factors and master curves in the time–temperature superposition principle (TTSP), the effects of asphalt migration on the dynamic modulus and the variation laws of the dynamic modulus of asphalt mixture after the occurrence of asphalt migration can be better construed at the quantitative level.
Networked Co-Curation: An Exploration of the Socio-Technical Specificities of Online Curation
Authors: Dekker Annet , Tedone Gaia
Published: July 2019

Online curation is shaped and defined not merely by its content, but just as much by the nature of the structure and the systems that are used by curators and artists. It could be argued that this applies to any medium, but as this essay will show, the Web profoundly influences the role of the curator in new ways. In this paper we show how curation on the Web is not merely concerned with presenting art, but that curation functions within a wider ecology of social and technical power relations. This shift is characterized by a collision of different interests driven by economic, cultural, and socio-political agendas, and can be framed as a new space of performativity: signaling a move from curating a set of objects to a conceptual and operational process that puts different constellations of human and machinic agents, objects and practices into relation with one another. This means that a curator needs to take into account a complex interrelated network of dependencies and contexts that are often invisible or incomprehensible to most people. In such a scenario online curation becomes ‘networked co-curation’ and shifts the attention from what is produced to how it is performed under the socio-technical conditions and relations that characterize the current state of the Web.
Weather Based Strawberry Yield Forecasts at Field Scale Using Statistical and Machine Learning Models
Authors: Maskey Mahesh L. , Pathak Tapan B , Dara Surendra K.
Published: July 2019

Strawberry is a high value and labor-intensive specialty crop in California. The three major fruit production areas on the Central Coast complement each other in producing fruits almost throughout the year. Forecasting strawberry yield with some lead time can help growers plan for required and often limited human resources and aid in making strategic business decisions. The objectives of this paper were to investigate the correlation among various weather parameters related with strawberry yield at the field level and to evaluate yield forecasts using the predictive principal component regression (PPCR) and two machine-learning techniques: (a) a single layer neural network (NN) and (b) generic random forest (RF). The meteorological parameters were a combination of the sensor data measured in the strawberry field, meteorological data obtained from the nearest weather station, and calculated agroclimatic indices such as chill hours. The correlation analysis showed that all of the parameters were significantly correlated with strawberry yield and provided the potential to develop weekly yield forecast models. In general, the machine learning technique showed better skills in predicting strawberry yields when compared to the principal component regression. More specifically, the NN provided the most skills in forecasting strawberry yield. While observations of one growing season are capable of forecasting crop yield with reasonable skills, more efforts are needed to validate this approach in various fields in the region.
Transient Receptor Potential Channel Expression Signatures in Tumor-Derived Endothelial Cells: Functional Roles in Prostate Cancer Angiogenesis
Authors: Bernardini Michela , Brossa Alessia , Chinigò Giorgia , Grolez Guillaume , Trimaglio Giulia , Allart Laurent , Hulot Audrey , Marot Guillemette , Genova Tullio , Joshi Aditi , Mattot Virginie , Fromont Gaelle , Munaron Luca , Bussolati Benedetta , Prevarskaya Natalia , Fiorio Pla Alessandra , Gkika Dimitra
Published: July 2019

Background: Transient receptor potential (TRP) channels control multiple processes involved in cancer progression by modulating cell proliferation, survival, invasion and intravasation, as well as, endothelial cell (EC) biology and tumor angiogenesis. Nonetheless, a complete TRP expression signature in tumor vessels, including in prostate cancer (PCa), is still lacking. Methods: In the present study, we profiled by qPCR the expression of all TRP channels in human prostate tumor-derived ECs (TECs) in comparison with TECs from breast and renal tumors. We further functionally characterized the role of the ‘prostate-associated’ channels in proliferation, sprout formation and elongation, directed motility guiding, as well as in vitro and in vivo morphogenesis and angiogenesis. Results: We identified three ‘prostate-associated’ genes whose expression is upregulated in prostate TECs: TRPV2 as a positive modulator of TEC proliferation, TRPC3 as an endothelial PCa cell attraction factor and TRPA1 as a critical TEC angiogenic factor in vitro and in vivo. Conclusions: We provide here the full TRP signature of PCa vascularization among which three play a profound effect on EC biology. These results contribute to explain the aggressive phenotype previously observed in PTEC and provide new putative therapeutic targets.
Mitochondrial Homeostasis and Cellular Senescence
Authors: Vasileiou Panagiotis , Evangelou Konstantinos , Vlasis Konstantinos , Fildisis Georgios , Panayiotidis Mihalis , Chronopoulos Efstathios , Passias Panagiotis-Georgios , Kouloukoussa Mirsini , Gorgoulis Vassilis , Havaki Sophia
Published: July 2019

Cellular senescence refers to a stress response aiming to preserve cellular and, therefore, organismal homeostasis. Importantly, deregulation of mitochondrial homeostatic mechanisms, manifested as impaired mitochondrial biogenesis, metabolism and dynamics, has emerged as a hallmark of cellular senescence. On the other hand, impaired mitostasis has been suggested to induce cellular senescence. This review aims to provide an overview of homeostatic mechanisms operating within mitochondria and a comprehensive insight into the interplay between cellular senescence and mitochondrial dysfunction.
Unified Assessment of the Effects of Van der Waals Interactions on the Structural and Electronic Properties of Some Layered Organic Solids κ-(BEDT-TTF)2X
Authors: Lazić Predrag , Milat Ognjen , Gumhalter Branko , Tomić Silvia
Published: July 2019

Proper inclusion of van der Waals interactions (vdW) in ab initio calculations based on the density functional theory (DFT) is crucial to describe soft, organic, layered solids such as κ -(BEDT-TTF) 2 X . Since no consensus has been reached on the reliability of available vdW DFT functionals, most of the first principles calculations have been based on experimental crystal structure data without any structural optimization. Here, we explore optimal DFT-based schemes that account for the effects of vdW interactions on the structural and electronic band properties of three paradigmatic charge transfer salts, κ -(BEDT-TTF) 2 Cu 2 (CN) 3 , κ -(BEDT-TTF) 2 Ag 2 (CN) 3 , and κ -(BEDT-TTF) 2 Cu[N(CN) 2 ]Cl, for which a unified optimization of the structure is possible. Detailed examination of the prototype test system κ -(BEDT-TTF) 2 Cu[N(CN) 2 ]Cl shows that the optB88-vdW functional performs slightly better than the PBE-vdW and that the choice of pseudopotentials is critical to obtaining realistic results.
Variability and Reproducibility of Directed and Undirected Functional MRI Connectomes in the Human Brain
Authors: Conti Allegra , Duggento Andrea , Guerrisi Maria , Passamonti Luca , Indovina Iole , Toschi Nicola
Published: July 2019

A growing number of studies are focusing on methods to estimate and analyze the functional connectome of the human brain. Graph theoretical measures are commonly employed to interpret and synthesize complex network-related information. While resting state functional MRI (rsfMRI) is often employed in this context, it is known to exhibit poor reproducibility, a key factor which is commonly neglected in typical cohort studies using connectomics-related measures as biomarkers. We aimed to fill this gap by analyzing and comparing the inter- and intra-subject variability of connectivity matrices, as well as graph-theoretical measures, in a large (n = 1003) database of young healthy subjects which underwent four consecutive rsfMRI sessions. We analyzed both directed (Granger Causality and Transfer Entropy) and undirected (Pearson Correlation and Partial Correlation) time-series association measures and related global and local graph-theoretical measures. While matrix weights exhibit a higher reproducibility in undirected, as opposed to directed, methods, this difference disappears when looking at global graph metrics and, in turn, exhibits strong regional dependence in local graphs metrics. Our results warrant caution in the interpretation of connectivity studies, and serve as a benchmark for future investigations by providing quantitative estimates for the inter- and intra-subject variabilities in both directed and undirected connectomic measures.
Parametrization of a Modified Friedman Kinetic Method to Assess Vine Wood Pyrolysis Using Thermogravimetric Analysis
Authors: Suárez Sergio , Rosas Jose Guillermo , Sánchez Marta Elena , López Roberto , Gómez Natalia , Cara-Jiménez Jorge
Published: July 2019

Common kinetic parameters were obtained for leached and non-leached samples of vine wood biomass. Both samples were considered to have different proportions of cellulose, hemicellulose, and lignin compositions as a result of the leaching process. The two samples were analyzed in terms of pyrolysis kinetic parameters using non-isothermal thermogravimetric analysis. Furthermore, the classic Friedman isoconversional method, a deconvolution procedure using the Fraser–Suzuki function, and a modified Friedman method from a previous study on the delay in conversion degree were satisfactorily applied. The observed difference when the deconvolution technique was applied suggests that the classic Friedman method is not adequate for studying the pyrolysis of individual vine wood biomass components. However, this issue was solved by studying the delay in conversion degree of both biomasses and calculating the kinetic parameters using the resulting information. This procedure was found to be useful for studying and comparing the kinetics of heterogeneous biomasses and has a sound scientific explanation, making this research a basis for future similar studies.
Gasification of Waste Cooking Oil to Syngas by Thermal Arc Plasma
Authors: Tamošiūnas Andrius , Gimžauskaitė Dovilė , Aikas Mindaugas , Uscila Rolandas , Praspaliauskas Marius , Eimontas Justas
Published: July 2019

The depletion and usage of fossil fuels causes environmental issues and alternative fuels and technologies are urgently required. Therefore, thermal arc water vapor plasma for a fast and robust waste/biomass treatment is an alternative to the syngas method. Waste cooking oil (WCO) can be used as an alternative potential feedstock for syngas production. The goal of this experimental study was to conduct experiments gasifying waste cooking oil to syngas. The WCO was characterized in order to examine its properties and composition in the conversion process. The WCO gasification system was quantified in terms of the produced gas concentration, the H2/CO ratio, the lower heating value (LHV), the carbon conversion efficiency (CCE), the energy conversion efficiency (ECE), the specific energy requirements (SER), and the tar content in the syngas. The best gasification process efficiency was obtained at the gasifying agent-to-feedstock (S/WCO) ratio of 2.33. At this ratio, the highest concentration of hydrogen and carbon monoxide, the H2/CO ratio, the LHV, the CCE, the ECE, the SER, and the tar content were 47.9%, 22.42%, 2.14, 12.7 MJ/Nm3, 41.3% 85.42%, 196.2 kJ/mol (or 1.8 kWh/kg), and 0.18 g/Nm3, respectively. As a general conclusion, it can be stated that the thermal arc-plasma method used in this study can be effectively used for waste cooking oil gasification to high quality syngas with a rather low content of tars.
Conceptual Framework of Antecedents to Trends on Permanent Magnet Synchronous Generators for Wind Energy Conversion Systems
Authors: Padmanathan K. , Kamalakannan N. , Sanjeevikumar P. , Blaabjerg F. , Holm-Nielsen J. B. , Uma G. , Arul R. , Rajesh R. , Srinivasan A. , Baskaran J.
Published: July 2019

Wind Energy Conversion System (WECS) plays an inevitable role across the world. WECS consist of many components and equipment’s such as turbines, hub assembly, yaw mechanism, electrical machines; power electronics based power conditioning units, protection devices, rotor, blades, main shaft, gear-box, mainframe, transmission systems and etc. These machinery and devices technologies have been developed on gradually and steadily. The electrical machine used to convert mechanical rotational energy into electrical energy is the core of any WECS. Many electrical machines (generator) has been used in WECS, among the generators the Permanent Magnet Synchronous Generators (PMSGs) have gained special focus, been connected with wind farms to become the most desirable due to its enhanced efficiency in power conversion from wind energy turbine. This article provides a review of literatures and highlights the updates, progresses, and revolutionary trends observed in WECS-based PMSGs. The study also compares the geared and direct-driven conversion systems. Further, the classifications of electrical machines that are utilized in WECS are also discussed. The literature review covers the analysis of design aspects by taking various topologies of PMSGs into consideration. In the final sections, the PMSGs are reviewed and compared for further investigations. This review article predominantly emphasizes the conceptual framework that shed insights on the research challenges present in conducting the proposed works such as analysis, suitability, design, and control of PMSGs for WECS.
Characteristic Analysis of the Peak Braking Force and the Critical Speed of Eddy Current Braking in a High-Speed Maglev
Authors: Chen Chuntao , Xu Jie , Yuan Xibo , Wu Xinzhen
Published: July 2019

In the eddy current braking system of high-speed maglev, the peak braking force and the critical speed are key factors determining the performance of eddy current braking force. In this paper, the analytical formula of eddy current braking force is derived by a subdomain method considering the skin effect of the induction plate, and, subsequently, the characteristics of peak braking force and critical speed are analyzed. The analytical model is set up in a 2D Cartesian coordinate system. The Poisson equations in each subdomain are listed by treating the vector magnetic potential as a variable. By combining the boundary conditions between two adjacent subdomains, the expressions of eddy current density and magnetic density in the induction plate are obtained. Then, the analytical formula of the eddy current braking force is obtained by the Ampere force formula. The results of finite-element analysis confirm the validity of the analytical calculation. The methods of improving the performance of eddy current braking force under high speed are proposed by parametric analysis of peak braking force and critical speed, which provides guidance for the design of the eddy current braking system in high-speed maglev.
The Foundation Fighting Blindness Plays an Essential and Expansive Role in Driving Genetic Research for Inherited Retinal Diseases
Authors: Shaberman Ben , Durham Todd
Published: July 2019

The Foundation Fighting Blindness leads a collaborative effort among patients and families, scientists, and the commercial sector to drive the development of preventions, treatments, and cures for inherited retinal diseases (IRDs). When the nonprofit was established in 1971, it sought the knowledge and insights of leaders in the retinal research field to guide its research funding decisions. While the Foundation’s early investments focused on gaining a better understanding of the genetic causes of IRDs, its portfolio of projects would come to include some of the most innovative approaches to saving and restoring vision, including gene replacement/augmentation therapies, gene editing, RNA modulation, optogenetics, and gene-based neuroprotection. In recent years, the Foundation invested in resources such as its patient registry, natural history studies, and genetic testing program to bolster clinical development and trials for emerging genetic therapies. Though the number of clinical trials for such therapies has surged over the last decade, the Foundation remains steadfast in its commitment to funding the initiatives that hold the most potential for eradicating the entire spectrum of IRDs.
Loss of a Fragile Chromosome Region leads to the Screwy Phenotype in Paramecium tetraurelia
Authors: Nekrasova Irina , Nikitashina Vera , Bhullar Simran , Arnaiz Olivier , Singh Deepankar P. , Meyer Eric , Potekhin Alexey
Published: July 2019

A conspicuous cell-shape phenotype known as “screwy” was reported to result from mutations at two or three uncharacterized loci in the ciliate Paramecium tetraurelia. Here, we describe a new screwy mutation, Spinning Top, which appeared spontaneously in the cross of an unrelated mutant with reference strain 51. The macronuclear (MAC) genome of the Spinning Top mutant is shown to lack a ~28.5-kb segment containing 18 genes at the end of one chromosome, which appears to result from a collinear deletion in the micronuclear (MIC) genome. We tested several candidate genes from the deleted locus by dsRNA-induced silencing in wild-type cells, and identified a single gene responsible for the phenotype. This gene, named Spade, encodes a 566-aa glutamine-rich protein with a C2HC zinc finger. Its silencing leads to a fast phenotype switch during vegetative growth, but cells recover a wild-type phenotype only 5–6 divisions after silencing is stopped. We analyzed 5 independently-obtained mutant alleles of the Sc1 locus, and concluded that all of them also lack the Spade gene and a number of neighboring genes in the MAC and MIC genomes. Mapping of the MAC deletion breakpoints revealed two different positions among the 5 alleles, both of which differ from the Spinning Top breakpoint. These results suggest that this MIC chromosome region is intrinsically unstable in strain 51.
Evaporite Dissolution Rate through an on-site Experiment into Piezometric Tubes Applied to the Real Case-Study of Quinis (NE Italy)
Authors: Calligaris Chiara , Ghezzi Lisa , Petrini Riccardo , Lenaz Davide , Zini Luca
Published: July 2019

The present paper deals with a field experiments on evaporite rock samples and groundwater investigations in the Quinis test site, a hamlet of the Enemonzo municipality in NE Italy, were sinkholes occurred in the past and are still occurring causing severe damage to the existing infrastructures. The area is characterised by a Carnian evaporitic bedrock made of gypsum and anhydrite mantled by alluvial and colluvial deposits. In order to evaluate the loss of weight and volume of the subcropping evaporites as responsible for sinkholes, a field-experiment was carried out. Inside seven piezometers, at different depths, evaporitic rock samples were exposed to the naturally occurring variable climatic conditions such as degree of humidity, different air flow and hydrodynamic. The rock samples were installed at the beginning of April 2017 in the dry sections of piezometric tubes, in the vadose zone and in the phreatic zone. Data related to water level fluctuations were recorded by using data-logger devices and highlight significant changes in the water table. After 13 months of data recording (May 2018), rock samples were removed, reweighted and the volume loss measured. In addition, water from piezometer-experiment, representative of the groundwater circulation, were collected at different depths. The obtained results indicate that rock sample reduction is dependent on the hydrological regime and water chemistry and not on the number of days during which the samples remained submersed. In particular, the water geochemistry highlights the possible role in gypsum/anhydrite dissolution due to NaCl water admixing in a complex scenario. In additional, the geochemical data highlight the occurrence of some potentially toxic elements (As, Fe, Mn) at concentrations of concern in some water. This approach represents a novel contribution in the study of karst hazard in evaporites adding a tile to the knowledge of the fast evolutionary processes which cause sinkhole formation.
Forecasting Term Structure of Interest Rates in Japan
Authors: Ishii Hokuto
Published: July 2019

In this paper, we examined and compared the forecast performances of the dynamic Nelson–Siegel (DNS), dynamic Nelson–Siegel–Svensson (DNSS), and arbitrage-free Nelson–Siegel (AFNS) models after the financial crisis period. The best model for the forecast performance is the DNSS model in the middle and long periods. The AFNS is inferior to the DNS model for long-period forecasting. In U.S. bond markets, AFNS is shown to be superior to DNS in the U.S. However, for Japanese data, there is no evidence that the AFNS is superior to the DNS model in the long forecast horizon.
Metabolic and Nutritional Characteristics of Long-Stay Critically Ill Patients
Authors: Viana Marina V. , Pantet Olivier , Bagnoud Geraldine , Martinez Arianne , Favre Eva , Charrière Mélanie , Favre Doris , Eckert Philippe , Berger Mette M.
Published: July 2019

Background: insufficient feeding is frequent in the intensive care unit (ICU), which results in poor outcomes. Little is known about the nutrition pattern of patients requiring prolonged ICU stays. The aims of our study are to describe the demographic, metabolic, and nutritional specificities of chronically critically ill (CCI) patients defined by an ICU stay >2 weeks, and to identify an early risk factor. Methods: analysis of consecutive patients prospectively admitted to the CCI program, with the following variables: demographic characteristics, Nutrition Risk Screening (NRS-2002) score, total daily energy from nutritional and non-nutritional sources, protein and glucose intakes, all arterial blood glucose values, length of ICU and hospital stay, and outcome (ICU and 90-day survival). Two phases were considered for the analysis: the first 10 days, and the next 20 days of the ICU stay. Statistics: parametric and non-parametric tests. Results: 150 patients, aged 60 ± 15 years were prospectively included. Median (Q1, Q3) length of ICU stay was 31 (26, 46) days. The mortality was 18% at ICU discharge and 35.3% at 90 days. Non-survivors were older (p = 0.024), tended to have a higher SAPSII score (p = 0.072), with a significantly higher NRS score (p = 0.033). Enteral nutrition predominated, while combined feeding was minimally used. All patients received energy and protein below the ICU’s protocol recommendation. The proportion of days with fasting was 10.8%, being significantly higher in non-survivors (2 versus 3 days; p = 0.038). Higher protein delivery was associated with an increase in prealbumin over time (r2 = 0.19, p = 0.027). Conclusions: High NRS scores may identify patients at highest risk of poor outcome when exposed to underfeeding. Further studies are required to evaluate a nutrition strategy for patients with high NRS, addressing combined parenteral nutrition and protein delivery.
Phenotypic and Genotypic Characterization of Escherichia coli Causing Urinary Tract Infections in Kidney-Transplanted Patients
Authors: Abo Basha Jonas , Kiel Matthias , Görlich Dennis , Schütte-Nütgen Katharina , Witten Anika , Pavenstädt Hermann , Kahl Barbara C. , Dobrindt Ulrich , Reuter Stefan
Published: July 2019

Urinary tract infection (UTI), frequently caused by uropathogenic Escherichia coli (UPEC), is the most common infection after kidney transplantation (KTx). Untreated, it can lead to urosepsis and impairment of the graft function. We questioned whether the UPEC isolated from KTx patients differed from the UPEC of non-KTx patients. Therefore, we determined the genome sequences of 182 UPEC isolates from KTx and control patients in a large German university clinic and pheno- and genotypically compared these two isolated groups. Resistance to the β-lactams, trimethoprim or trimethoprim/sulfamethoxazole was significantly higher among UPEC from KTx than from control patients, whereas both the isolated groups were highly susceptible to fosfomycin. Accordingly, the gene content conferring resistance to β-lactams or trimethoprim, but also to aminoglycosides, was significantly higher in KTx than in control UPEC isolates. E. coli isolates from KTx patients more frequently presented with uncommon UPEC phylogroups expressing higher numbers of plasmid replicons, but interestingly, less UPEC virulence-associated genes than the control group. We conclude that there is no defining subset of virulence traits for UPEC from KTx patients. The clinical history and immunocompromised status of KTx patients enables E. coli strains with low uropathogenic potential, but with increased antibiotic resistance to cause UTIs.
Thermal Effectiveness Enhancement of Autoclaved Aerated Concrete Wall with PCM-Contained Conical Holes to Reduce the Cooling Load
Authors: Thongtha Atthakorn , Khongthon Aitthi , Boonsri Thitinun , Hoy-Yen Chan
Published: July 2019

This work investigates and improves the thermal dynamics of autoclaved aerated concrete (AAC) wall containing phase change material (PCM). The PCM is paraffin wax loaded into conical holes drilled into the AAC. Filled AAC with three different numbers of PCM-filled holes (2, 3, and 4 conical holes, which are designated as AAC-2H, AAC-3H, and AAC-4H, respectively) as well as the unfilled original AAC were both tested under two different conditions: indoors (with controlled temperature) and outdoors (with actual weather). For the indoor experiment, a heater was used as a thermal source and set up to maintain the testing temperature at one of three levels: 40 °C, 50 °C, or 60 °C. The wall temperature was then measured on the surface with each horizontally-positioned wall as well as four different positions at various depths below the surface of the wall. It was found that AAC-4H was the optimum condition, which can produce outstandingly a time lag of approximately 27%, reduce a decrement factor of approximately 31%, and also decrease the room temperature. This reached approximately 9% when compared with that of ordinary AAC at the controlled testing temperature of 60 °C. All samples were further tested in actual weather to confirm the thermal performances of AAC-4H. Thermal effectiveness of AAC-4H was improved by extending approximately a 14.3% time lag, which reduces approximately a 4.3% decrement factor and achieving approximately 5% lower room temperature when compared with ordinary AAC.
Machinability of Luxury Vinyl Tiles during Plain Milling Using a Helical Cutter
Authors: Zhu Zhaolong , Cao Pingxiang , Guo Xiaolei , Wang Xiaodong , Zhang Fan , Gao Yu
Published: July 2019

In order to better provide a theoretical basis for the machining of luxury vinyl tiles, a helical milling experiment was conducted by using diamond cutting tools, and special attention was given to the trends of cutting force and surface roughness in respect to tool geometry and cutting parameters. The results showed that the resultant force was negatively correlated to the helix angle and cutting speed, but positively correlated with the cutting depth. Then, that the surface roughness increased with a decrease of the helix angle and an increase of cutting depth, while as cutting speed raised, the surface roughness first declined and then increased. Thirdly, the cutting depth was shown to have the greatest influence on both cutting force and surface roughness, followed by helix angle and cutting speed. Fourth, the contribution of cutting depth only was significant to cutting force, while both the helix angle and cutting speed had insignificant influence on the cutting force and surface roughness. Finally, the optimal cutting conditions were proposed for industrial production, in which the helix angle, cutting speed and cutting depth were 70°, 2200 m/min and 0.5 mm, respectively.
Nanomaterials for Wound Healing and Infection Control
Authors: Mihai Mara Madalina , Dima Monica Beatrice , Dima Bogdan , Holban Alina Maria
Published: July 2019

Wound healing has been intensely studied in order to develop an “ideal” technique that achieves expeditious recovery and reduces scarring to the minimum, thus ensuring function preservation. The classic approach to wound management is represented by topical treatments, such as antibacterial or colloidal agents, in order to prevent infection and promote a proper wound-healing process. Nanotechnology studies submicroscopic particles (maximum diameter of 100 nm), as well as correlated phenomena. Metal nanoparticles (e.g., silver, gold, zinc) are increasingly being used in dermatology, due to their beneficial effect on accelerating wound healing, as well as treating and preventing bacterial infections. Other benefits include: ease of use, less frequent dressing changes and a constantly moist wound environment. This review highlights recent findings regarding nanoparticle application in wound management.
Quasi-Periodic and Fractal Polymers: Energy Structure and Carrier Transfer
Authors: Mantela Marilena , Lambropoulos Konstantinos , Theodorakou Marina , Simserides Constantinos
Published: July 2019

We study the energy structure and the coherent transfer of an extra electron or hole along aperiodic polymers made of N monomers, with fixed boundaries, using B-DNA as our prototype system. We use a Tight-Binding wire model, where a site is a monomer (e.g., in DNA, a base pair). We consider quasi-periodic (Fibonacci, Thue–Morse, Double-Period, Rudin–Shapiro) and fractal (Cantor Set, Asymmetric Cantor Set) polymers made of the same monomer (I polymers) or made of different monomers (D polymers). For all types of such polymers, we calculate the highest occupied molecular orbital (HOMO) eigenspectrum and the lowest unoccupied molecular orbital (LUMO) eigenspectrum, the HOMO–LUMO gap and the density of states. We examine the mean over time probability to find the carrier at each monomer, the frequency content of carrier transfer (Fourier spectra, weighted mean frequency of each monomer, total weighted mean frequency of the polymer), and the pure mean transfer rate k. Our results reveal that there is a correspondence between the degree of structural complexity and the transfer properties. I polymers are more favorable for charge transfer than D polymers. We compare k ( N ) of quasi-periodic and fractal sequences with that of periodic sequences (including homopolymers) as well as with randomly shuffled sequences. Finally, we discuss aspects of experimental results on charge transfer rates in DNA with respect to our coherent pure mean transfer rates.
Forecasting the Wear of Operating Parts in an Abrasive Soil Mass Using the Holm-Archard Model
Authors: Napiórkowski Jerzy , Lemecha Magdalena , Konat Łukasz
Published: July 2019

This paper presents the forecasting of the wear of working elements in an abrasive soil mass using the theoretical wear model. One of the widely used models providing a basis for the relationships describing wear is the Holm-Archard model. This relationship describes abrasive wear because of the contact between two bodies. The model assumes that the wear of an operating part is directly proportional to the sliding force and distance and inversely proportional to the hardness of the material of the part. To date, the model has not been verified in the wear of a soil mass, which is a discrete friction surface. Four grades of steel resistant to abrasive wear, intended for the manufacturing of operating parts exposed to wear within a soil mass, Hardox 500, XAR 600, TBL Plus and B27, were subjected to testing. TBL Plus steel was characterised by the smallest wear irrespective of the soil type. In turn, the highest values of the wear were noted in the light soil for Hardox 500, in the medium soil for XAR 600, while in the heavy soil for B27. Based on the obtained results, a high correlation coefficient was noted, with the highest values obtained for light and heavy soils.