bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling of a Hybrid Steam Storage and Validation with an Industrial Ruths Steam Storage Line
Authors: Dusek Sabrina , Hofmann René
Published: March 2019

Phase change materials are used in latent heat thermal energy storages to store a high amount of energy during phase change. A hybrid storage concept was developed with the aim of utilizing this high storage capacity in combination with Ruths steam storages. In the concept, a container filled with phase change material is placed at the shell surface of the Ruths steam storage. This container can be divided into several chambers filled with different phase change materials. An arrangement of electrical heating elements or heat exchangers at the internal side of these chambers is also provided. In this paper, a model of the hybrid storage concept is developed. The model consists of different sub-models, which are connected to each other. The simulation results of a hybrid storage show how important the model is for the analysis of the concept. Furthermore, the validation of the Ruths steam storage sub-model with operational measurement data of a storage line is presented. A maximum deviation between the operational measurement data and the simulation results of 6.43% occurs in terms of pressure at the internal side of the pressure vessel. In addition, the latent heat thermal energy storage sub-model was checked with the analytic solution.
Fixing Efficiency Values by Unfixing Compressor Speed: Dynamic Test Method for Heat Pumps
Authors: Palkowski Carsten , Zottl Andreas , Malenkovic Ivan , Simo Anne
Published: March 2019

The growing market penetration of heat pumps indicates the need for a performance test method that better reflects the dynamic behavior of heat pumps. In this contribution, we developed and implemented a dynamic test method for the evaluation of the seasonal performance of heat pumps by means of laboratory testing. Current standards force the heat pump control inactive by fixing the compressor speed. In contrast, during dynamic testing, the compressor runs unfixed while the heat pump is subjected to a temperature profile. The profile consists of the different outdoor temperatures of a typical heating season based on the average European climate and also includes temperature changes to reflect the dynamic behavior of the heat pump. The seasonal performance can be directly obtained from the measured heating energy and electricity consumption making subsequent data interpolation and recalculation with correction factors obsolete. The method delivers results with high precision and high reproducibility and could be an appropriate method for a fair rating of heat pumps.
Study and Stability Analysis of Leading Phase Operation of a Large Synchronous Generator
Authors: Lv Yanling , Du Yizhi , Liu Qi , Hou Shiqiang , Zhang Jie
Published: March 2019

This paper proposes a two-dimensional finite element mathematical model taking the mf-15 simulation generator in the dynamic model laboratory as the research object. The electromagnetic performance of the motor under no-load and rated load was analyzed to verify the correctness of the model. By using the method of field-circuit coupling combined with simulation analysis, the limit value of the generator’s phase-in depth is determined, and the variation law of the electric and magnetic field distribution with the depth of the generator’s established Leading phase operation is analyzed, as well as the influence of the phase-in operation on the system’s operation stability. The results obtained provide a reference for the phase-in operation analysis of large generators.
Concentrating Solar Power Technologies
Authors: Răboacă Maria Simona , Badea Gheorghe , Enache Adrian , Filote Constantin , Răsoi Gabriel , Rata Mihai , Lavric Alexandru , Felseghi Raluca-Andreea
Published: March 2019

Nowadays, the evolution of solar energy use has turned into a profound issue because of the implications of many points of view, such as technical, social, economic and environmental that impose major constraints for policy-makers in optimizing solar energy alternatives. The topographical constraints regarding the availability of inexhaustible solar energy is driving field development and highlights the need for increasingly more complex solar power systems. The solar energy is an inexhaustible source of CO2 emission-free energy at a global level. Solar thermal technologies may produce electric power when they are associated with thermal energy storage, and this may be used as a disposable source of limitless energy. Furthermore, it can also be used in industrial processes. Using these high-tech systems in a large area of practice emboldens progress at the performance level. This work compiles the latest literature in order to provide a timely review of the evolution and worldwide implementation of Concentrated Solar Power—CSP—mechanization. The objective of this analysis is to provide thematic documentation as a basis for approaching the concept of a polygeneration solar system and the implementation possibilities. It also aims to highlight the role of the CSP in the current and future world energy system.
Production of Chips from Logging Residues and Their Quality for Energy: A Review of European Literature
Authors: Moskalik Tadeusz , Gendek Arkadiusz
Published: March 2019

Wood chips from logging residues are a renewable solid fuel that has become widely used in the energy sector. The current work presents a review of European papers on various aspects of wood chips production published in the years 2005–2018. The effects of the comminution method on the quality and energy parameters of the resulting wood chips were analysed. Most authors identified terrain and roadside chipping as the optimum technologies from the energy viewpoint. Furthermore, seasonal changes in the moisture content of wood chips have implications for their ash content and calorific value and determine the annual patterns of supplies to energy plants. In general, logging residues should be chipped approximately five to seven months after harvesting and delivered over economically feasible distances, which have increased in recent years due to the large dispersion of forest areas and energy plants. In a number of cases, logging residue chips did not meet the quality specifications contained in the relevant ISO standards, which may result in technological problems with their burning, especially in small to medium energy plants.
Contrasting Species Diversity and Values in Home Gardens and Traditional Parkland Agroforestry Systems in Ethiopian Sub-Humid Lowlands
Authors: Tadesse Eguale , Abdulkedir Abdu , Khamzina Asia , Son Yowhan , Noulèkoun Florent
Published: March 2019

Understanding the complex diversity of species and their potential uses in traditional agroforestry systems is crucial for enhancing the productivity of tropical systems and ensuring the sustainability of the natural resource base. The aim of this study is the evaluation of the role of home gardens and parklands, which are prominent tropical agroforestry systems, in the conservation and management of biodiversity. Our study quantified and compared the diversity of woody and herbaceous perennial species and their uses in traditional home gardens and parkland agroforestry systems under a sub-humid climate in western Ethiopia. A sociological survey of 130 household respondents revealed 14 different uses of the species, mostly for shade, fuelwood, food, and as traditional medicine. Vegetation inventory showed that the Fisher’s α diversity index and species richness were significantly higher in home gardens (Fisher’s α = 5.28 ± 0.35) than in parklands (Fisher’s α = 1.62 ± 0.18). Both systems were significantly different in species composition (Sørenson’s similarity coefficient = 35%). The differences occurred primarily because of the high intensity of management and the cultivation of exotic tree species in the home gardens, whereas parklands harbored mostly native flora owing to the deliberate retention and assisted regeneration by farmers. In home gardens, Mangifera indica L. was the most important woody species, followed by Cordia africana Lam. and Coffea arabica L. On the other hand, Syzygium guineense Wall. was the most important species in parklands, followed by C. africana and M. indica. The species diversity of agroforestry practices must be further augmented with both indigenous and useful, non-invasive exotic woody and herbaceous species, particularly in parklands that showed lower than expected species diversity compared to home-gardens.
Some Lessons Learned on Early Survival and Growth of Containerized, Locally-Sourced Ponderosa Pine Seedlings in the Davis Mountains of Western Texas, US
Authors: Vickers Lance A. , Houser James , Rooni James , Guldin James M.
Published: March 2019

The ponderosa pine forests in the Davis Mountains of western Texas recently experienced a major mortality event caused, in part, by an extended regional drought that predisposed trees and stands to mortality from both western pine beetle and wildfires. The loss of many overstory pines and the scarcity of natural ponderosa pine regeneration pose a considerable challenge to restoration. A commissioned study investigated artificial regeneration using containerized ponderosa pine seedlings with multiple planting seasons and vegetation management alternatives. Early survival was statistically greater for dormant season plantings than monsoon season plantings. Vegetation management treatments influenced early growth, survival, and herbivory rates. Physical weed control, which consisted of fibrous weed mats around the base of planted seedlings, showed early advantages over some vegetation management treatments in growth, survival and herbivory deterrence, but all vegetation management treatments had similar survival and herbivory results after 2.5 years. Early survival was poor in all treatments, mainly due to herbivory, which was identified as the principal short-term obstacle to artificial regeneration of ponderosa pine in the Davis Mountains. The larger question regarding feasibility of recovery in this isolated population, particularly if local climatic conditions become increasingly unfavorable, remains.
The Effects of Copper and Silver Nanoparticles on Container-Grown Scots Pine (Pinus sylvestris L.) and Pedunculate Oak (Quercus robur L.) Seedlings
Authors: Aleksandrowicz-Trzcińska Marta , Bederska-Błaszczyk Magdalena , Szaniawski Adam , Olchowik Jacek , Studnicki Marcin
Published: March 2019

Metal nanoparticles (NPs) are finding ever-wider applications in plant production (agricultural and forestry-related) as fertilisers, pesticides and growth stimulators. This makes it essential to examine their impact on a variety of plants, including trees. In the study detailed here, we investigated the effects of nanoparticles of silver and copper (i.e., AgNPs and CuNPs) on growth, and chlorophyll fluorescence, in the seedlings of Scots pine and pedunculate oak. We also compared the ultrastructure of needles, leaves, shoots and roots of treated and untreated plants, under transmission electron microscopy. Seedlings were grown in containers in a peat substrate, prior to the foliar application of NPs four times in the course of the growing season, at the four concentrations of 0, 5, 25 and 50 ppm. We were able to detect species-specific activity of the two types of NP. Among seedling pines, the impact of both types of NP at the concentrations supplied limited growth slightly. In contrast, no such effect was observed for the oaks grown in the trial. Equally, it was not possible to find ultrastructural changes in stems and roots associated with the applications of NPs. Cell organelles apparently sensitive to the action of both NPs (albeit only at the highest applied concentration of 50 ppm) were chloroplasts. The CuNP-treated oaks contained large plastoglobules, whereas those dosed with AgNP contained large starch granules. The NP-treated pines likewise exhibited large numbers of plastoglobules, while the chloroplasts of NP-treated plants in general presented shapes that changed from lenticular to round. In addition, large osmophilic globules were present in the cytoplasm. Reference to maximum quantum yields from photosystem II (Fv/Fm)—on the basis of chlorophyll a fluorescence measurements—revealed a slight debilitation of oak seedlings following the application of both kinds of NP at higher concentrations. In contrast, in pines, this variable revealed no influence of AgNPs, as well as a favourable effect due to the CuNPs applied at a concentration of 5 ppm. Our research also showed that any toxic impact on pine or oak seedlings due to the NPs was limited and only present with higher concentrations.
Innovative CO2 Injection Strategies in Carbonates and Advanced Modeling for Numerical Investigation
Authors: de Dios José Carlos , Le Gallo Yann , Marín Juan Andrés
Published: March 2019

Carbon sequestration in deep saline aquifers was recently developed at the industrial scale. CO2 injection experiences in carbonates are quite limited, most of them coming from projects carried out in porous mediums in the USA and Canada. Hontomín (Spain) is the actual on-shore injection pilot in Europe, being a naturally fractured carbonate reservoir where innovative CO2 injection strategies are being performed within the ENOS Project. CO2 migration through the fracture network existing on site produces hydrodynamic, mechanical and geochemical effectsdifferent from those caused by the injection in mediums with a high matrix permeability. The interpretation of these effects is required to design safe and efficient injection strategies in these formations. For this, it is necessary to determine the evolution of pressure, temperature and flow rate during the injection, as well as the period of pressure recovery during the fall-off phase. The first results from the not-continuous injections (8–24 h) conducted at Hontomín reveal the injection of liquid CO2 (density value of 0.828 t/m3) and the fluid transmissivity through the fractures. Taking into account the evolution of the pressure and flow rate showed variations of up to 23% and 30% respectively, which means that the relevant changes of injectivity took place. The results were modeled with a compositional dual media model which accounts for both temperature effects and multiphase flow hysteresis because alternative brine and CO2 injections were conducted. Advanced modeling shows the lateral extension of CO2 and the temperature disturbance away from the well.
Geoscience Methods in Real Estate Market Analyses Subjectivity Decrease
Authors: Renigier-Bilozor Malgorzata , Janowski Artur , Walacik Marek
Published: March 2019

Real estate management, including real estate market analysis, is part of a so-called geosystem. In recent years, the popularity of creating various types of systems and automatic solutions in real estate management, including those related to property classification and valuation, has been growing in the world, mainly to reduce the impact of human subjectivity, to increase the scope of analyses and reduce research time. A very important fact that should be underlined is that properties are strongly related to geolocation (space) and strongly determine it. Authors proposed in the paper solutions that highlight implementation of geoscience and “geo-approach” combined with fuzzy logic methods that allow to decrease subjectivity in property analyses and diminish uncertainty in decision making process. The proposed methodology involves three main problematic components of decision support system in property investment analyses development with the use of geo-technologies such as: determination of the database model; elaboration geo-property-zones with geoprocessing activities; identification of homogeneous group of properties transactions. The influence of spatial decision factor determined in the study lead to objective and precise calculation of value differentiation from 22 to 43% depending on the property’s remoteness to the sea.
GPR Imaging for Deeply Buried Objects: A Comparative Study Based on Compositing of Scanning Frequencies and a Chirp Excitation Function
Authors: Tilley Roger , Sadjadpour Hamid R. , Dowla Farid
Published: March 2019

Compositing of ground penetrating radar (GPR) scans of differing frequencies have been found to produce cleaner images at depth using the Gaussian mixture model (GMM) feature of the expectation-maximization (EM) algorithm. GPR scans at various heights (“Stand Off”), as well as ground-based scans, have been studied. In this paper, we compare the GPR response from a chirp excitation function-based radar with the response from the EM GMM algorithm compositing process, using the same mix of frequencies. A chirp excitation pulse was found to be effective in delineating the defined buried object, but the resulting image is less sharp than the GMM EM method.
A Qualitative Exploratory Analysis of Ecological Integrity for Safeguarding World Natural Heritage Sites: Case Study of Shiretoko Peninsula, Japan
Authors: Chakraborty Abhik , Takenaka Takeshi
Published: March 2019

This article reports the findings of an exploratory study on the complexity and challenges of managing UNESCO World Natural Heritage Sites (WNHS). Despite their protected status, the majority of the WNHS currently face severe anthropogenic stress. While several studies have analyzed this scenario with spatial analysis and review of global trends, this research provides a qualitative analysis of ongoing fragmentation and impact in a specific site by employing the Ecological Integrity (EI) concept to the Shiretoko Peninsula WNHS in Japan. Insights from key scientific literature are synthesized with those from research and monitoring of the Blakiston’s Fish Owl (a keystone species). Findings indicate that ecosystems of Shiretoko WNHS have not sufficiently recovered from the intensive anthropogenic disruption in the 20th century and in some cases face novel stressors from tourism development after the inscription. Besides, ongoing construction of roads and facilities affects fine-scale heterogeneity in the surrounding landscape. The findings highlight the urgent need of protecting lower trophic level species, stream and forest restoration, and restricting infrastructure development. This implies that WNHS managers must implement measures to meaningfully offset anthropogenic stress on EI, and WNHS management should be integrated with the management of its surrounding landscapes.
The Living Environment and Thermal Behaviours of Older South Australians: A Multi-Focus Group Study
Authors: van Hoof Joost , Bennetts Helen , Hansen Alana , Kazak Jan K. , Soebarto Veronica
Published: March 2019

Ageing brings about physiological changes that affect people’s thermal sensitivity and thermoregulation. The majority of older Australians prefer to age in place and modifications to the home environment are often required to accommodate the occupants as they age and possibly become frail. However, modifications to aid thermal comfort are not always considered. Using a qualitative approach this study aims to understand the thermal qualities of the existing living environment of older South Australians, their strategies for keeping cool in hot weather and warm in cold weather and to identify existing problems related to planning and house design, and the use of heating and cooling. Data were gathered via seven focus group sessions with 49 older people living in three climate zones in South Australia. The sessions yielded four main themes, namely ‘personal factors’, ‘feeling’, ‘knowing’ and ‘doing’. These themes can be used as a basis to develop information and guidelines for older people in dealing with hot and cold weather.
Acceptance of Online Medical Websites: An Empirical Study in China
Authors: Tang Yuan , Yang Yu-Tao , Shao Yun-Fei
Published: March 2019

As a new type of public health service product, online medical websites (OMWs) are becoming quite popular. OMWs can address patients’ basic medical problems remotely and give health guidance online. Compared to traditional hospitals, OMWs are more convenient and inexpensive, they can usually provide a better service for patients with poor medical conditions (especially in rural areas), and they also contribute to the rational distribution of medical resources. Therefore, key factors that affect patients’ acceptance of OMWs must be identified to contribute to public health. By integrating perceived risk (PR) and the technology acceptance model (TAM), we proposed a modified TAM and clarified how PR and other factors affect patients’ behavioral intention (BI) towards OMWs. A sample of 245 research participants in China took part in this study and the structural equation model (SEM) was used to test our hypotheses. The results revealed that perceived usefulness (PU) is a positive predictor of BI but has no significant effect on attitude (ATT), while perceived ease of use (PEOU) can affect BI through PU and attitude (ATT). Moreover, trust (TRU) was identified as a mediator of PR and PU/PEOU. Also, the doctor–patient relationship (DPR) was shown to moderate PR and TRU. In order to increase patients’ BI, OMW providers need further innovations to improve patients’ TRU and reduce their PR.
Standards Compliance and Health Implications of Bottled Water in Malawi
Authors: Chidya Russel C. G. , Singano Lazarus , Chitedze Isaac , Mourad Khaldoon A.
Published: March 2019

Many people around the globe prefer bottled water especially in developing countries, where tap water is not drinkable. This study investigated the quality of bottled drinking water sold in Lilongwe city, Malawi. Compliance with Malawi Standards (MS) 560 (2004) for natural mineral water, MS 699 (2004) for bottled water and the World Health Organisation guidelines for drinking water were examined. Bottled water from different 12 brands was purchased from local stores and analysed for its pH, total dissolved solids (TDS), EC, turbidity, Ca, Mg, Na, K, Fe, NO3−, Cl−, F−, SO42−, hardness, alkalinity, and Escherichia coli. A Hierarchical Cluster Analysis (HCA) resulted in two clusters in which most of the brands (92%, n = 12) belonged to one group. The two clusters and significant differences (ANOVA p < 0.05) in chemical compositions among the brands were attributed to the variations in the water source and the treatment processes. The results showed that 10 brands did not comply with the MS 699 (2004) turbidity standard (1 NTU) and the pH of one of the brands was below the minimum MS 699 (2004) standard of 6.50. This research showed that 12 brands had bottle labelling errors and discrepancies in chemical composition. The article highlighted the need for a strict inspection from the responsible governmental ministry to improve water quality and to adjust water bottles’ labels according to water characteristics.
Radio Frequency Electromagnetic Fields Exposure Assessment in Indoor Environments: A Review
Authors: Chiaramello Emma , Bonato Marta , Fiocchi Serena , Tognola Gabriella , Parazzini Marta , Ravazzani Paolo , Wiart Joe
Published: March 2019

Exposure to radiofrequency (RF) electromagnetic fields (EMFs) in indoor environments depends on both outdoor sources such as radio, television and mobile phone antennas and indoor sources, such as mobile phones and wireless communications applications. Establishing the levels of exposure could be challenging due to differences in the approaches used in different studies. The goal of this study is to present an overview of the last ten years research efforts about RF EMF exposure in indoor environments, considering different RF-EMF sources found to cause exposure in indoor environments, different indoor environments and different approaches used to assess the exposure. The highest maximum mean levels of the exposure considering the whole RF-EMF frequency band was found in offices (1.14 V/m) and in public transports (0.97 V/m), while the lowest levels of exposure were observed in homes and apartments, with mean values in the range 0.13–0.43 V/m. The contribution of different RF-EMF sources to the total level of exposure was found to show slightly different patterns among the indoor environments, but this finding has to be considered as a time-dependent picture of the continuous evolving exposure to RF-EMF.
Factors Influencing Consumer Purchase Intentions of Organically Grown Products in Shelly Centre, Port Shepstone, South Africa
Authors: Wekeza Siphelele Vincent , Sibanda Melusi
Published: March 2019

In the last few years, the market of organically grown products (OGPs) has continued to grow due to speculated concerns for the environment, food safety and health issues. The market for OGPs in South Africa appears to be under threat; with their demand outstripping their supply. In light of this background, there are relatively few studies on the consumer purchase intentions of OGPs in South Africa, and thus, less understanding about its demand market drivers. The purpose of this paper is to identify the factors influencing the purchase intentions of OGPs (fruits and vegetables) in Shelly Centre in Port Shepstone in Kwa-Zulu Natal Province of South Africa. Using a quantitative descriptive cross-sectional research design, a hundred and fifty (150) OGP consumers were selected through a systematic random sampling technique from three accredited OGP retail outlets namely Pick n’ Pay, Spar and Woolworths. Generally, descriptive results show that the interviewed consumers in Shelly Centre were reasonably educated and knowledgeable about OGPs. A higher proportion of the interviewed consumers in Shelly Centre consisted of women, employed and not of African descendant (ethnic group) consumers. Most were confident that OGPs are environmentally friendly, safe, high-quality products, and have a better taste compared to conventionally grown food products. A somewhat fair proportion expressed mixed feelings concerning the belief that OGPs are priced higher, their appeal to nature (smell), and their willingness to purchase OGPs regardless of price. Nonetheless, most were adamant that OGPs are difficult to find on the market. A multiple regression model analysis results reveal that consumer demographics; ethnicity (not of African descent) (p < 0.001), and monthly household income (p < 0.05) are statistically significant and positively influence the consumer purchase intentions of OGPs in Shelly Centre. Conversely, consumer perceptions that OGPs are priced higher (p < 0.05), have a better taste and of quality (p < 0.001), and the difficulty to find on the market (p < 0.001) are statistically significant and negatively influence the consumer purchase intentions of OGPs in Shelly Centre. The findings of this paper stress the need to design strategies and elements (marketing mix) to make OGPs affordable and readily available to consumers. Likewise, consumers from all ethnic groups and income levels need to be conscious of the environmental and health benefits of OGPs to make informed purchase decisions. To promote the purchase of OGPs; from a policy perspective, the government can offer support such as a consumer price subsidy to make OGPs affordable, and the provision of effective regulations and certification around the marketing of OGPs.
Rethinking Models of Outpatient Specialist Care in Type 2 Diabetes Using eHealth: Study Protocol for a Pilot Randomised Controlled Trial
Authors: Menon Anish , Fatehi Farhad , Bird Dominique , Darssan Darsy , Karunanithi Mohan , Russell Anthony , Gray Leonard
Published: March 2019

Conventional outpatient services are unlikely to meet burgeoning demand for diabetes services given increasing prevalence of diabetes, and resultant impact on the healthcare workforce and healthcare costs. Disruptive technologies (such as smartphone and wireless sensors) create an opportunity to redesign outpatient services. In collaboration, the Department of Diabetes and Endocrinology at Brisbane Princess Alexandra Hospital, the University of Queensland Centre for Health Services Research and the Australian e-Health Research Centre developed a mobile diabetes management system (MDMS) to support the management of complex outpatient type 2 diabetes mellitus (T2DM) adults. The system comprises of a mobile App, an automated text-messaging feedback and a clinician portal. Blood glucose levels (BGL) data are automatically transferred by Bluetooth-enabled glucose meter to the clinician portal via the mobile App. The primary aim of the study described here is to examine improvement in glycaemic control of a new model of care employing MDMS for patients with complex T2DM attending a tertiary level outpatient service. A two-group, 12-month, pilot pragmatic randomised control trial will recruit 44 T2DM patients. The control group will receive routine care. The intervention group will be supported by the MDMS enabling the participants to potentially better self-manage their diabetes, and the endocrinologists to remotely monitor BGL and to interact with patients through a variety of eHealth modalities. Intervention participants will be encouraged to complete relevant pathology tests, and report on current diabetes management through an online questionnaire. Using this information, the endocrinologist may choose to reschedule the appointment or substitute it with a telephone or video-consultation. This pilot study will guide the conduct of a large-scale study regarding the capacity for a new model of care. This model utilises multimodal eHealth strategies via the MDMS to primarily improve glycaemic control with secondary aims to improve patient experience, reduce reliance on physical clinics, and decrease service delivery cost.
Tracking Changes of Chinese Pre-Service Teachers’ Aerobic Fitness, Body Mass Index, and Grade Point Average Over 4-years of College
Authors: Keating Xiaofen , Shangguan Rulan , Xiao Kunpeng , Gao Xue , Sheehan Connor , Wang Liang , Colburn Jeff , Fan Yao , Wu Fei
Published: March 2019

Although increasing attention has been given to student academic achievement, usually measured by grade point average (GPA), and fitness in children and adolescents, much fewer studies have been conducted in higher education settings, especially in China. This study investigated the longitudinal associations of aerobic fitness (AF), body mass index (BMI), and GPA in Chinese pre-service teachers at a university. A longitudinal research design was employed to track changes in AF, BMI, and GPA, for a total of 1980 students for four years. Multi-level growth models were used to examine the interactive changes of the above three variables. It was found that GPA and BMI increased each year, while AF declined dramatically at the fourth year. The three-way interaction among GPA, gender, and BMI was significant, suggesting females who were overweight/obese had lower GPA. The data from the current study suggested that AF did not impact students’ GPA. Class standing (i.e., the fourth year) and gender (i.e., females) need to be taken into consideration when designing interventions to improve student overall fitness and academic performance in Chinese pre-service teacher populations.
Flammable Substances in Korea Considering the Domino Effect: Assessment of Safety Distance
Authors: Lee Hyo Eun , Yoon Seok J. , Sohn Jong-Ryeul , Huh Da-An , Lee Bong Woo , Moon Kyong Whan
Published: March 2019

Benzene, toluene, and xylene (BTX) are flammable substances used in a wide range of raw materials and products. Chemical accidents caused by flammable substances are different from leakage accidents of toxic materials. Initial explosions and fires may cause secondary or tertiary explosions, or fires with nearby flammable materials. This is called the domino effect. In cases of leakage accidents, it is possible to prevent accidents through early control of the leakage to the outside or by bypassing, but it is difficult to cope with explosions because they occur instantaneously. To prevent explosions due to the domino effect, a safety distance must be set. Safety distances vary widely by country. In the case of the United States (US) or the European Union (EU), safety distances are set in various ways depending on the chemical industry and the amount of flammable substances being handled. However, countries such as Korea, Taiwan, and Dubai have comprehensive regulation, and the safety distances are small. In this study, we simulated the range of overpressure at which other chemical equipment could explode when an explosion occurs in a flammable BTX storage tank. There are three types of analysis methods of vapor cloud explosion. PHAST (Process Hazard Analysis Software Tool) and ALOHA (Areal Location of Hazardous Atmosphere) were selected to model explosions using three methods (trinitrotoluene equivalence method, the Netherlands Organization multi-energy method, and Baker-Strehlow-Tang method). The results indicated that the safety distances in the US and EU showed low probability of a domino effect, but those in Korea, Dubai, and Taiwan could lead to a secondary explosions. Therefore, it is necessary to propose a reasonable method to determine safety distances considering the amount and physicochemical characteristics of the flammable substances being used.
Effect of A22 on the Conformation of Bacterial Actin MreB
Authors: Awuni Elvis , Mu Yuguang
Published: March 2019

The mechanism of the antibiotic molecule A22 is yet to be clearly understood. In a previous study, we carried out molecular dynamics simulations of a monomer of the bacterial actin-like MreB in complex with different nucleotides and A22, and suggested that A22 impedes the release of Pi from the active site of MreB after the hydrolysis of ATP, resulting in filament instability. On the basis of the suggestion that Pi release occurs on a similar timescale to polymerization and that polymerization can occur in the absence of nucleotides, we sought in this study to investigate a hypothesis that A22 impedes the conformational change in MreB that is required for polymerization through molecular dynamics simulations of the MreB protofilament in the apo, ATP+, and ATP-A22+ states. We suggest that A22 inhibits MreB in part by antagonizing the ATP-induced structural changes required for polymerization. Our data give further insight into the polymerization/depolymerization dynamics of MreB and the mechanism of A22.
In Silico Analysis of Homologous Heterodimers of Cruzipain-Chagasin from Structural Models Built by Homology
Authors: Reyes-Espinosa Francisco , Juárez-Saldivar Alfredo , Palos Isidro , Herrera-Mayorga Verónica , García-Pérez Carlos , Rivera Gildardo
Published: March 2019

The present study gives an overview of the binding energetics of the homologous heterodimers of cruzipain−chagasin based on the binding energy (ΔGb) prediction obtained with FoldX. This analysis involves a total of 70 homologous models of the cruzipain−chagasin complex which were constructed by homology from the combinatory variation of nine papain-like cysteine peptidase structures and seven cysteine protease inhibitor structures (as chagasin-like and cystatin-like inhibitors). Only 32 systems have been evaluated experimentally, ΔGbexperimental values previously reported. Therefore, the result of the multiple analysis in terms of the thermodynamic parameters, are shown as relative energy |ΔΔG| = |ΔGbfrom FoldX − ΔGbexperimental|. Nine models were identified that recorded |ΔΔG| < 1.3, five models to 2.8 > |ΔΔG| > 1.3 and the other 18 models, values of |ΔΔG| > 2.8. The energetic analysis of the contribution of ΔH and ΔS to ΔGb to the 14-molecular model presents a ΔGb mostly ΔH-driven at neutral pH and at an ionic strength (I) of 0.15 M. The dependence of ΔGb(I,pH) at 298 K to the cruzipain−chagasin complex predicts a linear dependence of ΔGb(I). The computational protocol allowed the identification and prediction of thermodynamics binding energy parameters for cruzipain−chagasin-like heterodimers.
Cellular Gene Expression during Hepatitis C Virus Replication as Revealed by Ribosome Profiling
Authors: Gerresheim Gesche , Bathke Jochen , Michel Audrey , Andreev Dmitri , Shalamova Lyudmila , Rossbach Oliver , Hu Pan , Glebe Dieter , Fricke Markus , Marz Manja , Goesmann Alexander , Kiniry Stephen , Baranov Pavel , Shatsky Ivan , Niepmann Michael
Published: March 2019

Background: Hepatitis C virus (HCV) infects human liver hepatocytes, often leading to liver cirrhosis and hepatocellular carcinoma (HCC). It is believed that chronic infection alters host gene expression and favors HCC development. In particular, HCV replication in Endoplasmic Reticulum (ER) derived membranes induces chronic ER stress. How HCV replication affects host mRNA translation and transcription at a genome wide level is not yet known. Methods: We used Riboseq (Ribosome Profiling) to analyze transcriptome and translatome changes in the Huh-7.5 hepatocarcinoma cell line replicating HCV for 6 days. Results: Established viral replication does not cause global changes in host gene expression—only around 30 genes are significantly differentially expressed. Upregulated genes are related to ER stress and HCV replication, and several regulated genes are known to be involved in HCC development. Some mRNAs (PPP1R15A/GADD34, DDIT3/CHOP, and TRIB3) may be subject to upstream open reading frame (uORF) mediated translation control. Transcriptional downregulation mainly affects mitochondrial respiratory chain complex core subunit genes. Conclusion: After establishing HCV replication, the lack of global changes in cellular gene expression indicates an adaptation to chronic infection, while the downregulation of mitochondrial respiratory chain genes indicates how a virus may further contribute to cancer cell-like metabolic reprogramming (“Warburg effect”) even in the hepatocellular carcinoma cells used here.
HDAC Inhibitors: Therapeutic Potential in Fibrosis-Associated Human Diseases
Authors: Yoon Somy , Kang Gaeun , Eom Gwang Hyeon
Published: March 2019

Fibrosis is characterized by excessive deposition of the extracellular matrix and develops because of fibroblast differentiation during the process of inflammation. Various cytokines stimulate resident fibroblasts, which differentiate into myofibroblasts. Myofibroblasts actively synthesize an excessive amount of extracellular matrix, which indicates pathologic fibrosis. Although initial fibrosis is a physiologic response, the accumulated fibrous material causes failure of normal organ function. Cardiac fibrosis interferes with proper diastole, whereas pulmonary fibrosis results in chronic hypoxia; liver cirrhosis induces portal hypertension, and overgrowth of fibroblasts in the conjunctiva is a major cause of glaucoma surgical failure. Recently, several reports have clearly demonstrated the functional relevance of certain types of histone deacetylases (HDACs) in various kinds of fibrosis and the successful alleviation of the condition in animal models using HDAC inhibitors. In this review, we discuss the therapeutic potential of HDAC inhibitors in fibrosis-associated human diseases using results obtained from animal models.
Immunopathogenic Mechanisms and Novel Immune-Modulated Therapies in Rheumatoid Arthritis
Authors: Chen Shyi-Jou , Lin Gu-Jiun , Chen Jing-Wun , Wang Kai-Chen , Tien Chiung-Hsi , Hu Chih-Fen , Chang Chia-Ning , Hsu Wan-Fu , Fan Hueng-Chuen , Sytwu Huey-Kang
Published: March 2019

Rheumatoid arthritis (RA) is a chronic, inflammatory autoimmune disease of unknown etiology. It is characterized by the presence of rheumatoid factor and anticitrullinated peptide antibodies. The orchestra of the inflammatory process among various immune cells, cytokines, chemokines, proteases, matrix metalloproteinases (MMPs), and reactive oxidative stress play critical immunopathologic roles in the inflammatory cascade of the joint environment, leading to clinical impairment and RA. With the growing understanding of the immunopathogenic mechanisms, increasingly novel marked and potential biologic agents have merged for the treatment of RA in recent years. In this review, we focus on the current understanding of pathogenic mechanisms, highlight novel biologic disease-modifying antirheumatic drugs (DMRADs), targeted synthetic DMRADs, and immune-modulating agents, and identify the applicable immune-mediated therapeutic strategies of the near future. In conclusion, new therapeutic approaches are emerging through a better understanding of the immunopathophysiology of RA, which is improving disease outcomes better than ever.
Inhibition of Triple-Negative Breast Cancer Cell Aggressiveness by Cathepsin D Blockage: Role of Annexin A1
Authors: Zóia Mariana Alves Pereira , Azevedo Fernanda Van Petten , Vecchi Lara , Mota Sara Teixeira Soares , Rodovalho Vinícius de Rezende , Cordeiro Antonielle Oliveira , Correia Lucas Ian Veloso , Silva Anielle Christine Almeida , Ávila Veridiana de Melo Rodrigues , Araújo Thaise Gonçalves de , Goulart Luiz Ricardo
Published: March 2019

Triple-negative breast cancers (TNBCs) are more aggressive than other breast cancer (BC) subtypes and lack effective therapeutic options. Unraveling marker events of TNBCs may provide new directions for development of strategies for targeted TNBC therapy. Herein, we reported that Annexin A1 (AnxA1) and Cathepsin D (CatD) are highly expressed in MDA-MB-231 (TNBC lineage), compared to MCF-10A and MCF-7. Since the proposed concept was that CatD has protumorigenic activity associated with its ability to cleave AnxA1 (generating a 35.5 KDa fragment), we investigated this mechanism more deeply using the inhibitor of CatD, Pepstatin A (PepA). Fourier Transform Infrared (FTIR) spectroscopy demonstrated that PepA inhibits CatD activity by occupying its active site; the OH bond from PepA interacts with a CO bond from carboxylic acids of CatD catalytic aspartate dyad, favoring the deprotonation of Asp33 and consequently inhibiting CatD. Treatment of MDA-MB-231 cells with PepA induced apoptosis and autophagy processes while reducing the proliferation, invasion, and migration. Finally, in silico molecular docking demonstrated that the catalytic inhibition comprises Asp231 protonated and Asp33 deprotonated, proving all functional results obtained. Our findings elucidated critical CatD activity in TNBC cell trough AnxA1 cleavage, indicating the inhibition of CatD as a possible strategy for TNBC treatment.
Transcriptome Profile of the Variegated Ficus microcarpa c.v. Milky Stripe Fig Leaf
Authors: Shih Tin-Han , Lin Szu-Hsien , Huang Meng-Yuan , Huang Wen-Dar , Yang Chi-Ming
Published: March 2019

Photosynthetic properties and transcriptomic profiles of green and white sectors of Ficus microcarpa (c.v. milky stripe fig) leaves were examined in naturally variegated plants. An anatomic analysis indicated that chloroplasts of the white sectors contained a higher abundance of starch granules and lacked stacked thylakoids. Moreover, no photosynthetic rate was detected in the white sectors. Transcriptome profile and differential expressed gene (DEG) analysis showed that genes encoding PSII core proteins were down-regulated in the white sectors. In genes related to chlorophyll metabolism, no DEGs were identified in the biosynthesis pathway of chlorophyll. However, genes encoding the first step of chlorophyll breakdown were up-regulated. The repression of genes involved in N-assimilation suggests that the white sectors were deprived of N. The mutation in the transcription factor mitochondrial transcription termination factor (mTERF) suggests that it induces colorlessness in leaves of the milky stripe fig.
Genome-Wide Genetic Diversity and Population Structure of Tunisian Durum Wheat Landraces Based on DArTseq Technology
Authors: Robbana Cyrine , Kehel Zakaria , Ben Naceur M’barek , Sansaloni Carolina , Bassi Filippo , Amri Ahmed
Published: March 2019

Tunisia, being part of the secondary center of diversity for durum wheat, has rich unexploited landraces that are being continuously lost and replaced by high yielding modern cultivars. This study aimed to investigate the genetic diversity and population structure of 196 durum wheat lines issued from landraces collected from Tunisia using Diversity Array Technology sequencing (DArTseq) and to understand possible ways of introduction in comparing them to landraces from surrounding countries. A total of 16,148 polymorphic DArTseq markers covering equally the A and B genomes were effective to assess the genetic diversity and to classify the accessions. Cluster analysis and discriminant analysis of principal components (DAPC) allowed us to distinguish five distinct groups that matched well with the farmer’s variety nomenclature. Interestingly, Mahmoudi and Biskri landraces constitute the same gene pool while Jenah Zarzoura constitutes a completely different group. Analysis of molecular variance (AMOVA) showed that the genetic variation was among rather than within the landraces. DAPC analysis of the Tunisian, Mediterranean and West Asian landraces confirmed our previous population structure and showed a genetic similarity between the Tunisian and the North African landraces with the exception of Jenah Zarzoura being the most distant. The genomic characterization of the Tunisian collection will enhance their conservation and sustainable use.
The Significance of Calcium in Photosynthesis
Authors: Wang Quan , Yang Sha , Wan Shubo , Li Xinguo
Published: March 2019

As a secondary messenger, calcium participates in various physiological and biochemical reactions in plants. Photosynthesis is the most extensive biosynthesis process on Earth. To date, researchers have found that some chloroplast proteins have Ca2+-binding sites, and the structure and function of some of these proteins have been discussed in detail. Although the roles of Ca2+ signal transduction related to photosynthesis have been discussed, the relationship between calcium and photosynthesis is seldom systematically summarized. In this review, we provide an overview of current knowledge of calcium’s role in photosynthesis.
Comprehensive Genomic Analysis and Expression Profiling of Diacylglycerol Kinase (DGK) Gene Family in Soybean (Glycine max) under Abiotic Stresses
Authors: Carther Kue Foka Idrice , Ketehouli Toi , Ye Nan , Yang Yan-Hai , Wang Nan , Dong Yuan-Yuan , Yao Na , Liu Xiu-Ming , Liu Wei-Can , Li Xiao-Wei , Wang Fa-Wei , Li Hai-Yan
Published: March 2019

Diacylglycerol kinase (DGK) is an enzyme that plays a pivotal role in abiotic and biotic stress responses in plants by transforming the diacylglycerol into phosphatidic acid. However, there is no report on the characterization of soybean DGK genes in spite of the availability of the soybean genome sequence. In this study, we performed genome-wide analysis and expression profiling of the DGK gene family in the soybean genome. We identified 12 DGK genes (namely GmDGK1-12) which all contained conserved catalytic domains with protein lengths and molecular weights ranging from 436 to 727 amino acids (aa) and 48.62 to 80.93 kDa, respectively. Phylogenetic analyses grouped GmDGK genes into three clusters—cluster I, cluster II, and cluster III—which had three, four, and five genes, respectively. The qRT-PCR analysis revealed significant GmDGK gene expression levels in both leaves and roots coping with polyethylene glycol (PEG), salt, alkali, and salt/alkali treatments. This work provides the first characterization of the DGK gene family in soybean and suggests their importance in soybean response to abiotic stress. These results can serve as a guide for future studies on the understanding and functional characterization of this gene family.