bluuebunny/crossref_metadata_2025 huggingface dataset:
Building Energy Retrofit Measures in Hot-Summer–Cold-Winter Climates: A Case Study in Shanghai
Authors: Hong Yuanda , Ezeh Collins I. , Deng Wu , Hong Sung-Hugh , Peng Zhen
Published: September 2019

Building retrofit measures provide a significant means of mitigating the effect of climate change on buildings by enhancing building energy performance at a beneficial cost-effectiveness. An insight into the applicable building retrofit measures within a climate zone will guide the optimisation framework to attaining sustainability in architecture and the built environment. This article presents a brief overview of recent studies on retrofit measures and its application on a variety of buildings in hot-summer–cold-winter climates, with emphasis on Shanghai. Findings show that the major retrofit measures include improvement in the building envelope, heating, ventilation and cooling (HVAC) and lighting, supported by photovoltaic (PV) systems, accordingly. Furthermore, the study identifies key elements and plausible challenges for the evaluation of building retrofit measures in this region. In this regard, financial barriers and lack of standards and regulatory support are the main challenges identified. These insights provide a systematic approach to guide building researchers, practitioners and decision-makers in the design and development of existing and new retrofit measures for the future of rapidly growing cities with a broad climate variation scope.
Application of Response Surface Analysis to Evaluate the Effect of Concentrations of Ammonia and Propionic Acid on Acetate-Utilizing Methanogenesis
Authors: Shin Seung Gu , Lee Joonyeob , Do Trong Hoan , Kim Su In , Hwang Seokhwan
Published: September 2019

Ammonia and propionate are known inhibitors of anaerobic methanogenesis at higher concentrations, and are likely to coexist in digesters treating high-strength wastewater. Therefore, this study was conducted to assess the effects of ammonia and propionate on acetate-utilizing methanogenesis when they coexist. Response surface analysis with face-centered central composite design was used to explore the total ammonia nitrogen (TAN) level of 2–5 g/L and the propionate level of 2–8 g/L in acetate-fed batch incubation. Two models were successfully derived to estimate the lag period and the methane yield in response to the concentrations of the two chemicals. The lag period was affected by both inhibitors, with clues obtained of a synergistic effect at a higher concentration rage ([TAN] > 3.5 g/L and [propionate] > 5 g/L). The methane yield was also affected by the two inhibitors; between the two, it was more significantly dependent on the TAN concentration than on the propionate concentration. Real-time PCR showed that Methanosarcinaceae was the major methanogen group in this system. The results of this study improve our understanding of the inhibition of biogas reactors.
Investigations on EMI Mitigation Techniques: Intent to Reduce Grid-Tied PV Inverter Common Mode Current and Voltage
Authors: Subramaniam Umashankar , Bhaskar Sagar Mahajan , J.Almakhles Dhafer , Padmanaban Sanjeevikumar , Leonowicz Zbigniew
Published: September 2019

Power inverters produce common mode voltage (CMV) and common mode current (CMC) which cause high-frequency electromagnetic interference (EMI) noise, leakage currents in electrical drives application and grid-connected systems, which consequently drops the efficiency of the system considerably. This CMV can be mitigated by designing suitable EMI filters and/or investigating the effects of different modulation strategies. In this paper, the effect of various modulation techniques over CMV and CMC are investigated for two-level and three-level inverters. It is observed that the modified third harmonic injection method reduced the CMV and CMC in the system by 60%. This modified pulse width modulation (PWM) technique is employed along with EMI chokes which results in reduced distortion of the system.
Development of an SVR Model for the Fault Diagnosis of Large-Scale Doubly-Fed Wind Turbines Using SCADA Data
Authors: Tang Mingzhu , Chen Wei , Zhao Qi , Wu Huawei , Long Wen , Huang Bin , Liao Lida , Zhang Kang
Published: September 2019

Fault diagnosis and forecasting contribute significantly to the reduction of operating and maintenance associated costs, as well as to improve the resilience of wind turbine systems. Different from the existing fault diagnosis approaches using monitored vibration and acoustic data from the auxiliary equipment, this research presents a novel fault diagnosis and forecasting approach underpinned by a support vector regression model using data obtained by the supervisory control and data acquisition system (SCADA) of wind turbines (WT). To operate, the extraction of fault diagnosis features is conducted by measuring SCADA parameters. After that, confidence intervals are set up to guide the fault diagnosis implemented by the support vector regression (SVR) model. With the employment of confidence intervals as the performance indicators, an SVR-based fault detecting approach is then developed. Based on the WT SCADA data and the SVR model, a fault diagnosis strategy for large-scale doubly-fed wind turbine systems is investigated. A case study including a one-year monitoring SCADA data collected from a wind farm in Southern China is employed to validate the proposed methodology and demonstrate how it works. Results indicate that the proposed strategy can support the troubleshooting of wind turbine systems with high precision and effective response.
Study on the Effect of Cable Group Laying Mode on Temperature Field Distribution and Cable Ampacity
Authors: Xiong Lan , Chen Yonghui , Jiao Yang , Wang Jie , Hu Xiao
Published: September 2019

The reliability and service life of power cables is closely related to the cable ampacity and temperature rise. Therefore, studying the temperature field distribution and the cable ampacity is helpful to improve the construction guidelines of cable manufacturers. Taking a 8.7/15 kV YJV 1 × 400 XLPE three-loop power cable as the research object, cable temperature is calculated by IEC-60287 thermal circuit method and numerical simulation method, respectively. The results show that the numerical simulation method is more in line with the actual measured temperature, and the relative error is only 0.32% compared with the actual measured temperature. The temperature field and air velocity field of cluster cables with different laying methods are analyzed by finite element method. The corresponding cable ampacity are calculated by secant method. The results show that when the cable is laid at the bottom of the cable trench, the cable current is 420 A, which is 87.5% of the regular laying. Under irregular laying mode, the temperature of cable is higher than that of regular laying mode and the cable ampacity is lower than that of regular laying mode. At the same time, a multiparameter online monitoring system is developed to online monitor the temperature, water level and smoke concentration of the cable.
Stages in the Dynamics of Hydrate Formation and Consequences for Design of Experiments for Hydrate Formation in Sediments
Authors: Kvamme Bjørn , Coffin Richard B. , Zhao Jinzhou , Wei Na , Zhou Shouwei , Li Qingping , Saeidi Navid , Chien Yu-Chien , Dunn-Rankin Derek , Sun Wantong , Zarifi Mojdeh
Published: September 2019

Natural gas hydrates in sediments can never reach thermodynamic equilibrium. Every section of any hydrate-filled reservoir is unique and resides in a stationary balance that depends on many factors. Fluxes of hydrocarbons from below support formation of new hydrate, and inflow of water through fracture systems leads to hydrate dissociation. Mineral/fluid/hydrate interaction and geochemistry are some of the many other factors that determine local hydrate saturation in the pores. Even when using real sediments from coring it is impossible to reproduce in the laboratory a natural gas hydrate reservoir which has developed over geological time-scales. In this work we discuss the various stages of hydrate formation, with a focus on dynamic rate limiting processes which can lead to trapped pockets of gas and trapped liquid water inside hydrate. Heterogeneous hydrate nucleation on the interface between liquid water and the phase containing the hydrate former rapidly leads to mass transport limiting films of hydrate. These hydrate films can delay the onset of massive, and visible, hydrate growth by several hours. Heat transport in systems of liquid water and hydrate is orders of magnitude faster than mass transport. We demonstrate that a simple mass transport model is able to predict induction times for selective available experimental data for CO2 hydrate formation and CH4 hydrate formation. Another route to hydrate nucleation is towards mineral surfaces. CH4 cannot adsorb directly but can get trapped in water structures as a secondary adsorption. H2S has a significant dipole moment and can adsorb directly on mineral surfaces. The quadropole-moment in CO2 also plays a significant role in adsorption on minerals. Hydrate that nucleates toward minerals cannot stick to the mineral surfaces so the role of these nucleation sites is to produce hydrate cores for further growth elsewhere in the system. Various ways to overcome these obstacles and create realistic hydrate saturation in laboratory sediment are also discussed.
Fault Characteristic and Low Voltage Ride-Through Requirements Applicability Analysis for a Permanent Magnet Synchronous Generator-Based Wind Farm
Authors: Chen Wei , Zheng Taiying , Han Junfei
Published: September 2019

As the penetration of wind energy is being dramatically increased, the impact of wind energy on the power system should be roundly studied, especially for the fault characteristics analysis and applicability analysis of low voltage ride-through (LVRT) requirements for a whole wind farm (WF) and an individual wind turbine generator (WTG). This paper firstly describes a detailed modeling of a permanent magnet synchronous generator (PMSG)-based WF and analyzes the fault characteristics of the WF under various fault conditions. The validation of the fault characteristics analysis is carried out with the EMTP-RV generated data, with the consideration of different fault positions, fault types, and wind speeds. The relay protection and the related grid code are also taken into account. In addition, the applicability analysis of LVRT requirements for a WF and a WTG is also implemented, from the points of minimal grid-connection time and minimal dynamic reactive current support ability. The fault characteristic analysis of a PMSG-based WF could be helpful for developing new control or protection methods for a PMSG-based WF. Meanwhile, the applicability analysis of LVRT requirements could serve as a reference for WTG manufacturers, WF administrators, and grid operator.
Thermal State of the Blake Ridge Gas Hydrate Stability Zone (GHSZ)—Insights on Gas Hydrate Dynamics from a New Multi-Phase Numerical Model
Authors: Burwicz Ewa , Rüpke Lars
Published: September 2019

Marine sediments of the Blake Ridge province exhibit clearly defined geophysical indications for the presence of gas hydrates and a free gas phase. Despite being one of the world’s best-studied gas hydrate provinces and having been drilled during Ocean Drilling Program (ODP) Leg 164, discrepancies between previous model predictions and reported chemical profiles as well as hydrate concentrations result in uncertainty regarding methane sources and a possible co-existence between hydrates and free gas near the base of the gas hydrate stability zone (GHSZ). Here, by using a new multi-phase finite element (FE) numerical model, we investigate different scenarios of gas hydrate formation from both single and mixed methane sources (in-situ biogenic formation and a deep methane flux). Moreover, we explore the evolution of the GHSZ base for the past 10 Myr using reconstructed sedimentation rates and non-steady-state P-T solutions. We conclude that (1) the present-day base of the GHSZ predicted by our model is located at the depth of ~450 mbsf, thereby resolving a previously reported inconsistency between the location of the BSR at ODP Site 997 and the theoretical base of the GHSZ in the Blake Ridge region, (2) a single in-situ methane source results in a good fit between the simulated and measured geochemical profiles including the anaerobic oxidation of methane (AOM) zone, and (3) previously suggested 4 vol.%–7 vol.% gas hydrate concentrations would require a deep methane flux of ~170 mM (corresponds to the mass of methane flux of 1.6 × 10−11 kg s−1 m−2) in addition to methane generated in-situ by organic carbon (POC) degradation at the cost of deteriorating the fit between observed and modelled geochemical profiles.
Comparison of Productivity and Cost between Two Integrated Harvesting Systems in South Korea
Authors: Cho Min-Jae , Choi Yun-Sung , Paik Seung-Ho , Mun Ho-Seong , Cha Du-Song , Han Sang-Kyun , Oh Jae-Heun
Published: September 2019

Interest in the production of renewable energy using forest biomass is increasing in South Korea, and improved knowledge on operations logistics to lower biomass harvesting costs is needed. This study aimed to build a low-cost forest-biomass harvesting system by analyzing the costs of two integrated (cut-to-length and whole-tree) harvesting systems for logs and logging residues. Two integrated harvesting systems were carried out in the clear-cut mixed forest on a steep slope. Compared to the cut-to-length system that separately extracts logs and logging residues in a forest, the cable whole-tree harvesting system can save $8.8/green weight ton (Gwt) because it requires no additional yarding operation cost of logging residues. Moreover, a breakeven analysis shows that the required machine utilization rates that favor whole-tree harvesting systems over cut-to-length harvesting were more than 70% for cable harvesting systems. The introduction of the whole-tree harvesting system is, therefore, required to produce forest biomass at a low cost. In the future, studies on forest-biomass processing and transportation systems will be needed to provide a biomass feedstock supply cost from stump to biomass power plant.
Understory Vegetation Dynamics across a Poplar Plantation Chronosequence in Reclaimed Coastal Saline Soil
Authors: Poudel Daya Ram , Chen Han Y. H. , KC Mohan , Ge Zhiwei , Bown Horacio E. , Ruan Honghua
Published: September 2019

Although the understory vegetation abundance, diversity, and composition associated with stand development in natural forests have been well reported, only a few studies have examined the age-related changes of understory vegetation in fast-growing planted forests in reclaimed soils. This study measured the understory vegetation and soil variables in 8-, 12-, and 18-year-old poplar plantations in reclaimed coastal saline soil of Eastern China. This study examined how the abundance, diversity, and composition changed with stand development and the soil variables. Further, structural equation modeling (SEM) was used to evaluate the direct and indirect factors influencing the abundance and plant diversity throughout stand development. Herb abundance was significantly higher in the youngest and oldest stands, whereas shrub abundance was higher in the middle-aged stands. Shannon’s diversity index was significantly higher in the youngest stand for herbs, whereas it was highest in the middle-aged stands for shrubs. A multivariate analysis revealed that the herb and shrub composition were influenced by the stand age, total soil carbon and soil pH. The most parsimonious SEM model showed the negative direct effects of the stand age and the negative indirect effects of the stand age via the soil variables on shrub abundance, shrub diversity, and herb diversity, suggesting that the increase of overstory biomass with the stand age reduces resources available for the understory. Our results revealed that understory diversity and composition might change with stand development mediated by the changes in understory light and soil resources in fast-growing plantations.
An Explicit Meshless Point Collocation Solver for Incompressible Navier-Stokes Equations
Authors: Bourantas George C. , Zwick Benjamin F. , Joldes Grand R. , Loukopoulos Vassilios C. , Tavner Angus C. R. , Wittek Adam , Miller Karol
Published: September 2019

We present a strong form, meshless point collocation explicit solver for the numerical solution of the transient, incompressible, viscous Navier-Stokes (N-S) equations in two dimensions. We numerically solve the governing flow equations in their stream function-vorticity formulation. We use a uniform Cartesian embedded grid to represent the flow domain. We discretize the governing equations using the Meshless Point Collocation (MPC) method. We compute the spatial derivatives that appear in the governing flow equations, using a novel interpolation meshless scheme, the Discretization Corrected Particle Strength Exchange (DC PSE). We verify the accuracy of the numerical scheme for commonly used benchmark problems including lid-driven cavity flow, flow over a backward-facing step and unbounded flow past a cylinder. We have examined the applicability of the proposed scheme by considering flow cases with complex geometries, such as flow in a duct with cylindrical obstacles, flow in a bifurcated geometry, and flow past complex-shaped obstacles. Our method offers high accuracy and excellent computational efficiency as demonstrated by the verification examples, while maintaining a stable time step comparable to that used in unconditionally stable implicit methods. We estimate the stable time step using the Gershgorin circle theorem. The stable time step can be increased through the increase of the support domain of the weight function used in the DC PSE method.
A New Fractional Integration Operational Matrix of Chebyshev Wavelets in Fractional Delay Systems
Authors: Malmir Iman
Published: September 2019

Fractional integration operational matrix of Chebyshev wavelets based on the Riemann–Liouville fractional integral operator is derived directly from Chebyshev wavelets for the first time. The formulation is accurate and can be applied for fractional orders or an integer order. Using the fractional integration operational matrix, new Chebyshev wavelet methods for finding solutions of linear-quadratic optimal control problems and analysis of linear fractional time-delay systems are presented. Different numerical examples are solved to show the accuracy and applicability of the new Chebyshev wavelet methods.
Investigating the Prevalence and Predictors of Injury Occurrence in Competitive Hip Hop Dancers: Prospective Analysis
Authors: Ursej Eva , Sekulic Damir , Prus Dasa , Gabrilo Goran , Zaletel Petra
Published: September 2019

Hip hop is a popular form of competitive and recreational sport worldwide, but studies rarely investigate injury prevalence and factors associated with injury occurrence in this sport. This study aimed to prospectively examine injury occurrence in hip hop dancers in a three-month period and to evaluate potential predictors of injury occurrence in hip hop dancers. The participants were 129 competitive hip hop dancers (114 females, 17.95 ± 4.15 years of age). Study predictors were obtained at study baseline and included sociodemographic factors, sport-related factors, previous injury status, anthropometric and body build indices (body height, mass, body mass index, and body composition variables), and dynamic balance performance (obtained by the Star Excursion Balance Test—SEBT). The outcome was injury occurrence, which was prospectively observed once a week by the Oslo Sports Trauma Research Center Overuse Injury Questionnaire (OSTRC). During the course of the study, 101 injuries occurred, equating to an annual injury incidence of 312%. On average, each dancer suffered 0.78 injuries (95% Confidence Interval (95% CI): 0.61–0.97) across a study period of three months (0.76 (95% CI: 0.60–0.95) and 0.93 (95% CI: 0.75–1.13), in females and males, respectively; Mann Whitney Z-value: 0.68, p = 0.52). Seventeen percent of dancers suffered multiple injuries, and 49% of all injuries were time-loss injuries. The knee was the most frequently injured body location (42% of all reported injuries), followed by the back region (32%) and the ankle (15%). Previous injury was a strong predictor of injury occurrence (Odds Ratio: 3.76, 95% CI: 1.87–4.59). Lower injury risk was evidenced among those participants who achieved better scores on several SEBT variables, irrespective of gender and previous injury status; with no significant influence of anthropometric and body build variables on injury occurrence. This study highlighted a high injury rate in hip hop dancers. Dancers and coaches should be informed about the certain protective effects of dynamic balance on the prevention of musculoskeletal injury in hip hop in order to assure safe and effective practices. The usage of SEBT as a convenient and cheap testing procedure is encouraged in other dance disciplines.
Correlates of School Children’s Handwashing: A Study in Tibetan Primary Schools
Authors: Sun Chang , Wang Qingzhi , Poudel Adhikari Sasmita , Ye Ruixue , Meng Sha , Wu Yuju , Mao Yuping , Raat Hein , Zhou Huan
Published: September 2019

Hand hygiene, including handwashing by children, has been reported to contribute to the prevention of various infectious conditions. This study aims to explore the correlates of handwashing behavior among 1690 fourth to sixth grade primary school students in 19 Tibetan primary schools (Golog, Qinghai, China). The theory of reasoned action (TRA) was applied. Data was collected by questionnaire. Structural equation modeling (SEM) analysis showed that students’ attitude (β = 0.22, 95% CI 0.13–0.31) and subjective norms in terms of compliance to teachers’, parents’ and peers’ suggestions to wash hands (β = 0.09, 95% CI 0.01–0.18) were directly associated with students’ handwashing behavior. Students’ knowledge (β = 0.04, 95% CI 0.03–0.07) had an indirect association with handwashing behavior, mediated by students’ attitudes and subjective norms. Subjective norms (β = 0.12, 95% CI 0.07–0.17) were also indirectly correlated with handwashing through students’ attitudes. Therefore, our study supported the theory of reasoned action through our findings that students’ attitude and knowledge, and also attitudes from teachers, parents and peers were correlated with student handwashing behavior. Students reported higher level of compliance to teachers than to their parents and classmates. Based on this information, we recommend teacher-involved participatory hygiene education to promote students’ handwashing behaviors in areas at high risk for infectious diseases that can be prevented by handwashing.
Construction of Ecological Security Patterns in Nature Reserves Based on Ecosystem Services and Circuit Theory: A Case Study in Wenchuan, China
Authors: Xu Jianying , Fan Feifei , Liu Yanxu , Dong Jianquan , Chen Jixing
Published: September 2019

Facing the demands of biodiversity conservation and ecosystem service improvement, the spatial pattern optimization of nature reserves has always been a research topic of interest. However, there remains a lack of methodological guidance in the planning of nature reserves and the surrounding areas. To promote the landscape sustainability of nature reserves, we constructed ecological security patterns (ESPs) with two scenarios as a case study in Wenchuan, China. In detail, the ecological sources were identified by ecosystem service evaluation, and the resistance surface was characterized by the habitat quality. The ecological corridors were determined based on circuit theory and the minimum cumulative resistance model. The ecological sources were mainly aggregated in the protected areas, with an area of more than 1000 ha; the high-resistance values were mainly in the area with dense roads or high elevation. There were 21 corridors in the scenario of only optimizing the nature reserve, while 31 corridors were identified when considering non-nature reserves, and the landscape connectivity was enhanced accordingly. The result supported constructing the ESPs between nature and non-nature reserves in Wenchuan to further protect pandas, and a methodological contribution was made to understand the differences of ESPs between them, thus supporting a methodological formulation of sustainable landscape patterns.
Enhancement of COD Removal from Oilfield Produced Wastewater by Combination of Advanced Oxidation, Adsorption and Ultrafiltration
Authors: Dai Xiaodong , Fang Jian , Li Lei , Dong Yan , Zhang Jianhua
Published: September 2019

The wastewater produced from the oilfield is chemically corrosive due to high salinity in combination with high temperatures. It is also rich in contaminants, such as oil, polyacrylamide, emulsions, suspended solid, etc. The density difference between the oil and water in the wastewater is low, which makes separation via gravity difficult. In this study, a combined pilot treatment is studied, which includes Fenton oxidation, settlement, activated carbon adsorption, and ultrafiltration (UF). The operational conditions of Fenton oxidation are optimized based on alleviating the fouling of the UF membrane. When the Fenton oxidation was operated at the molar ratio of H2O2 to FeSO4 3:1 and pH 2.2–2.5, the UF membrane could operate continuously for 20 h without cleaning. The membrane was fouled by the organics (oil/grease) and polymer, which can be effectively removed by composite cleaning reagent consisting of 0.1% NaOH and 0.1% sodium dodecylbenzenesulfonate (SDBS). With the UF treatment, the chemical oxygen demand (COD) of the effluent was less than 50 mg/L, which could meet the upgraded standard.
Occupational Exposures in an Equestrian Centre to Respirable Dust and Respirable Crystalline Silica
Authors: Bulfin Kathleen , Cowie Hilary , Galea Karen S. , Connolly Alison , Coggins Marie Ann
Published: September 2019

Sand-based products are regularly used as footing material on indoor equestrian arenas, creating a potential occupational exposure risk for respirable crystalline silica (RCS) for equestrian workers training and exercising horses in these environments. The objective of this study was to evaluate an equestrian worker’s personal RCS and respirable dust (RD) exposure. Sixteen personal full-shift RD measurements were collected from an equestrian worker and analysed for RD, quartz and cristobalite. Geometric mean exposures of 0.12 mg m−3 and 0.02 mg m−3 were calculated for RD and RCS concentrations, respectively. RCS exposures of between 0.01 to 0.09 mg m−3 were measured on days when the indoor arena surface was not watered, compared to lower exposures (<LOD-0.03 mg m−3) on days when the indoor arena was watered (p < 0.01); however, manual watering is time intensive and less likely to be implemented in practice. This small-scale study provides new data on RCS and RD exposures among equestrian workers. RCS exposures are within the range considered to be associated with increased risk for lung cancer. The use of dust control solutions such as water suppression should be promoted for equestrian work in horse riding arenas. Equestrian workers need to receive occupational health training on the health risks associated with RCS exposure.
Residential Proximity to Agricultural Fields and Neurological and Mental Health Outcomes in Rural Adults in Matlab, Bangladesh
Authors: M. Khan Khalid , Karnati Janesh , Hamid Ipsita , Koceja David , Zahirul Islam Mohammad , Khan Md Alfazal
Published: September 2019

Pesticide exposure is an important rural public health concern that is linked to a spectrum of health outcomes in farmers. However, little is known about these effects on residents living in close proximity to agricultural fields and who are not involved in regular farming. This paper compared the effects of residential proximity to farming lands on a number of neurological and mental health outcomes in adults. A cross-sectional study was performed on 57 adults involved in farming only occasionally in rural Matlab in Bangladesh. A health and demographic surveillance system (HDSS) and geocoding were used to define proximity to the agricultural field. Neurological health was measured using the trail making test, vibrotactile threshold measurement, and dominant ulnar nerve conduction velocity (NCV) amplitude. An adapted Center for Epidemiological Studies Depression scale (CES-D) questionnaire was used to evaluate mental health. Results indicated that respondents living near agricultural fields had significantly higher vibrotactile threshold in big toes (p < 0.004) and needed a longer time to complete the trail making test (p < 0.004) than those living far from fields after accounting for the covariates. Results of this pilot study suggest further investigations to establish the impact of pesticide exposure among occasional and non-farmers on neurological health outcomes.
Selectivity and Market Timing Ability of Fund Managers: Comparative Analysis of Islamic and Conventional HSBC Saudi Mutual Funds
Authors: Zouaoui Marwa
Published: September 2019

This paper empirically compares the market timing, the stock selection and the performance persistence of Islamic and conventional HSBC Saudi mutual funds by using monthly returns from April 2011 to December 2018. The data was grouped into five portfolios based on geographical investment basis (locally, Arab, internationally) and Sharia compliance (Islamic and conventional). The empirical results indicate that Islamic funds underperformed conventional funds internationally but not locally. Findings suggest that the market selectivity skills of managers in the Islamic funds are better than the conventional funds. In addition, only the managers of Saudi conventional funds investing internationally have a good market timing skills, thus, they are able to beat the market index by predicting its movements and buying and selling accordingly. Furthermore, this study gives a brief idea about the performance persistence of HSBC Saudi funds. The results confirm existence of the persistence performance when the funds do not apply Sharia law and when they are instead focused internationally.
Review of Big Data and Processing Frameworks for Disaster Response Applications
Authors: Cumbane Silvino Pedro , Gidófalvi Győző
Published: September 2019

Natural hazards result in devastating losses in human life, environmental assets and personal, and regional and national economies. The availability of different big data such as satellite imageries, Global Positioning System (GPS) traces, mobile Call Detail Records (CDRs), social media posts, etc., in conjunction with advances in data analytic techniques (e.g., data mining and big data processing, machine learning and deep learning) can facilitate the extraction of geospatial information that is critical for rapid and effective disaster response. However, disaster response systems development usually requires the integration of data from different sources (streaming data sources and data sources at rest) with different characteristics and types, which consequently have different processing needs. Deciding which processing framework to use for a specific big data to perform a given task is usually a challenge for researchers from the disaster management field. Therefore, this paper contributes in four aspects. Firstly, potential big data sources are described and characterized. Secondly, the big data processing frameworks are characterized and grouped based on the sources of data they handle. Then, a short description of each big data processing framework is provided and a comparison of processing frameworks in each group is carried out considering the main aspects such as computing cluster architecture, data flow, data processing model, fault-tolerance, scalability, latency, back-pressure mechanism, programming languages, and support for machine learning libraries, which are related to specific processing needs. Finally, a link between big data and processing frameworks is established, based on the processing provisioning for essential tasks in the response phase of disaster management.
Tumor Dormancy and Interplay with Hypoxic Tumor Microenvironment
Authors: Butturini Elena , Carcereri de Prati Alessandra , Boriero Diana , Mariotto Sofia
Published: September 2019

The tumor microenvironment is a key factor in disease progression, local resistance, immune-escaping, and metastasis. The rapid proliferation of tumor cells and the aberrant structure of the blood vessels within tumors result in a marked heterogeneity in the perfusion of the tumor tissue with regions of hypoxia. Although most of the tumor cells die in these hypoxic conditions, a part of them can adapt and survive for many days or months in a dormant state. Dormant tumor cells are characterized by cell cycle arrest in G0/G1 phase as well as a low metabolism, and are refractive to common chemotherapy, giving rise to metastasis. Despite these features, the cells retain their ability to proliferate when conditions improve. An understanding of the regulatory machinery of tumor dormancy is essential for identifying early cancer biomarkers and could provide a rationale for the development of novel agents to target dormant tumor cell populations. In this review, we examine the current knowledge of the mechanisms allowing tumor dormancy and discuss the crucial role of the hypoxic microenvironment in this process.
Small RNA Mobility: Spread of RNA Silencing Effectors and its Effect on Developmental Processes and Stress Adaptation in Plants
Authors: Pagliarani Chiara , Gambino Giorgio
Published: September 2019

Plants are exposed every day to multiple environmental cues, and tight transcriptome reprogramming is necessary to control the balance between responses to stress and processes of plant growth. In this context, the silencing phenomena mediated by small RNAs can drive transcriptional and epigenetic regulatory modifications, in turn shaping plant development and adaptation to the surrounding environment. Mounting experimental evidence has recently pointed to small noncoding RNAs as fundamental players in molecular signalling cascades activated upon exposure to abiotic and biotic stresses. Although, in the last decade, studies on stress responsive small RNAs increased significantly in many plant species, the physiological responses triggered by these molecules in the presence of environmental stresses need to be further explored. It is noteworthy that small RNAs can move either cell-to-cell or systemically, thus acting as mobile silencing effectors within the plant. This aspect has great importance when physiological changes, as well as epigenetic regulatory marks, are inspected in light of plant environmental adaptation. In this review, we provide an overview of the categories of mobile small RNAs in plants, particularly focusing on the biological implications of non-cell autonomous RNA silencing in the stress adaptive response and epigenetic modifications.
Spilanthol Inhibits Inflammatory Transcription Factors and iNOS Expression in Macrophages and Exerts Anti-inflammatory Effects in Dermatitis and Pancreatitis
Authors: Bakondi Edina , Singh Salam Bhopen , Hajnády Zoltán , Nagy-Pénzes Máté , Regdon Zsolt , Kovács Katalin , Hegedűs Csaba , Madácsy Tamara , Maléth József , Hegyi Péter , Demény Máté Á. , Nagy Tibor , Kéki Sándor , Szabó Éva , Virág László
Published: September 2019

Activated macrophages upregulate inducible nitric oxide synthase (iNOS) leading to the profuse production of nitric oxide (NO) and, eventually, tissue damage. Using macrophage NO production as a biochemical marker of inflammation, we tested different parts (flower, leaf, and stem) of the medicinal plant, Spilanthes acmella. We found that extracts prepared from all three parts, especially the flowers, suppressed NO production in RAW macrophages in response to interferon-γ and lipopolysaccharide. Follow up experiments with selected bioactive molecules from the plant (α-amyrin, β-caryophylline, scopoletin, vanillic acid, trans-ferulic acid, and spilanthol) indicated that the N-alkamide, spilanthol, is responsible for the NO-suppressive effects and provides protection from NO-dependent cell death. Spilanthol reduced the expression of iNOS mRNA and protein and, as a possible underlying mechanism, inhibited the activation of several transcription factors (NFκB, ATF4, FOXO1, IRF1, ETS, and AP1) and sensitized cells to downregulation of Smad (TF array experiments). The iNOS inhibitory effect translated into an anti-inflammatory effect, as demonstrated in a phorbol 12-myristate 13-acetate-induced dermatitis and, to a smaller extent, in cerulein-induced pancreatitis. In summary, we demonstrate that spilanthol inhibits iNOS expression, NO production and suppresses inflammatory TFs. These events likely contribute to the observed anti-inflammatory actions of spilanthol in dermatitis and pancreatitis.
Genome-Wide Identification and Characterization of the UBP Gene Family in Moso Bamboo (Phyllostachys edulis)
Authors: Wu Ruihua , Shi Yanrong , Zhang Qian , Zheng Wenqing , Chen Shaoliang , Du Liang , Lu Cunfu
Published: September 2019

The largest group of deubiquitinases—ubiquitin-specific proteases (UBPs)—perform extensive and significant roles in plants, including the regulation of development and stress responses. A comprehensive analysis of UBP genes has been performed in Arabidopsis thaliana, but no systematic study has been conducted in moso bamboo (Phyllostachys edulis). In this study, the genome-wide identification, classification, gene, protein, promoter region characterization, divergence time, and expression pattern analyses of the UBPs in moso bamboo were conducted. In total, 48 putative UBP genes were identified in moso bamboo, which were divided into 14 distinct subfamilies in accordance with a comparative phylogenetic analysis using 132 full-length protein sequences, including 48, 27, 25, and 32 sequences from moso bamboo, A. thaliana, rice (Oryza sativa), and purple false brome (Brachypodium distachyon), respectively. Analyses of the evolutionary patterns and divergence levels revealed that the PeUBP genes experienced a duplication event approximately 15 million years ago and that the divergence between PeUBP and OsUBP occurred approximately 27 million years ago. Additionally, several PeUBP members were significantly upregulated under abscisic acid, methyl jasmonate, and salicylic acid treatments, indicating their potential roles in abiotic stress responses in plants.
Identification and Functional Analysis of the CLAVATA3/EMBRYO SURROUNDING REGION (CLE) Gene Family in Wheat
Authors: Li Zheng , Liu Dan , Xia Yu , Li Ziliang , Niu Na , Ma Shoucai , Wang Junwei , Song Yulong , Zhang Gaisheng
Published: September 2019

CLAVATA3/EMBRYO SURROUNDING REGION (CLE) peptides are post-translationally cleaved and modified peptides from their corresponding pre-propeptides. Although they are only 12 to 13 amino acids in length, they are important ligands involved in regulating cell proliferation and differentiation in plant shoots, roots, vasculature, and other tissues. They function by interacting with their corresponding receptors. CLE peptides have been studied in many plants, but not in wheat. We identified 104 TaCLE genes in the wheat genome based on a genome-wide scan approach. Most of these genes have homologous copies distributed on sub-genomes A, B, and D. A few genes are derived from tandem duplication and segmental duplication events. Phylogenetic analysis revealed that TaCLE genes can be divided into five different groups. We obtained functional characterization of the peptides based on the evolutionary relationships among the CLE peptide families of wheat, rice, and Arabidopsis, and expression pattern analysis. Using chemically synthesized peptides (TaCLE3p and TaCLE34p), we found that TaCLE3 and TaCLE34 play important roles in regulating wheat and Arabidopsis root development, and wheat stem development. Overexpression analysis of TaCLE3 in Arabidopsis revealed that TaCLE3 not only affects the development of roots and stems, but also affects the development of leaves and fruits. These data represent the first comprehensive information on TaCLE family members.
Modulation of Tetraspanin 32 (TSPAN32) Expression in T Cell-Mediated Immune Responses and in Multiple Sclerosis
Authors: Lombardo Salvo Danilo , Mazzon Emanuela , Basile Maria Sofia , Campo Giorgia , Corsico Federica , Presti Mario , Bramanti Placido , Mangano Katia , Petralia Maria Cristina , Nicoletti Ferdinando , Fagone Paolo
Published: September 2019

Tetraspanins are a conserved family of proteins involved in a number of biological processes including, cell–cell interactions, fertility, cancer metastasis and immune responses. It has previously been shown that TSPAN32 knockout mice have normal hemopoiesis and B-cell responses, but hyperproliferative T cells. Here, we show that TSPAN32 is expressed at higher levels in the lymphoid lineage as compared to myeloid cells. In vitro activation of T helper cells via anti-CD3/CD28 is associated with a significant downregulation of TSPAN32. Interestingly, engagement of CD3 is sufficient to modulate TSPAN32 expression, and its effect is potentiated by costimulation with anti-CD28, but not anti-CTLA4, -ICOS nor -PD1. Accordingly, we measured the transcriptomic levels of TSPAN32 in polarized T cells under Th1 and Th2 conditions and TSPAN32 resulted significantly reduced as compared with unstimulated cells. On the other hand, in Treg cells, TSPAN32 underwent minor changes upon activation. The in vitro data were finally translated into the context of multiple sclerosis (MS). Encephalitogenic T cells from Myelin Oligodendrocyte Glycoprotein (MOG)-Induced Experimental Autoimmune Encephalomyelitis (EAE) mice showed significantly lower levels of TSPAN32 and increased levels of CD9, CD53, CD82 and CD151. Similarly, in vitro-activated circulating CD4 T cells from MS patients showed lower levels of TSPAN32 as compared with cells from healthy donors. Overall, these data suggest an immunoregulatory role for TSPAN32 in T helper immune response and may represent a target of future immunoregulatory therapies for T cell-mediated autoimmune diseases.
Mutagenic Study of Benzimidazole Derivatives with (+S9) and without (−S9) Metabolic Activation
Authors: Azahar Nurul Hafizan , Ab dullah Siti Soleha , Abdullah Rozaini , Ahmat Norizan , Md Akim Abdah , Ab Hamid Hasiah
Published: September 2019

Benzimidazole derivatives have a diverse range of biological activities, including antiulcer, antihypertensive, antiviral, antifungal, anti-inflammatory, and anticancer. Despite these activities, previous studies have revealed that some of the derivatives can induce mutations. This study aimed to screen for potential mutagenic activities of novel benzimidazole derivatives 1–4 using the Ames test and to study their structure–activity relationship (SAR). An Ames test was carried out on two strains of Salmonella typhimurium (TA98 and TA100) in the absence and presence of metabolic activation. Genetic analysis was performed prior to the Ames test to determine the genotypes of the bacterial tester strains. Both bacterial strains showed dependency on histidine with the presence of rfa mutation, uvrB deletion, and plasmid pKM101. Further, all derivatives tested showed no mutagenic activity in the absence of metabolic activation in both tester strains. However, in the presence of metabolic activation, compound 1 appeared to induce mutation at 2.5 µg/plate when tested against the TA98 strain. These results suggest that the absence of the -OH group at the ortho-position over the phenyl ring might be the cause of increased mutagenic activity in compound 1. Additionally, the presence of mutagenic activity in compound 1 when it was metabolically activated indicates that this compound is a promutagen.
First Insights into the Intrapuparial Development of Bactrocera dorsalis (Hendel): Application in Predicting Emergence Time for Tephritid Fly Control
Authors: Jing Tian-Xing , Zhang Ying-Xin , Dou Wei , Jiang Xin-Yi , Wang Jin-Jun
Published: September 2019

Intrapuparial development is a special pattern of metamorphosis in cyclorrhaphous flies, in which the pupa forms in an opaque, barrel-like puparium. This has been well studied in forensic insects for age estimations. In this study, the intrapuparial development of a quarantine agricultural pest, Bactrocera dorsalis (Hendel), was studied under a constant temperature of 27 ± 1 °C and 70 ± 5% relative humidity. Results showed that intrapuparial development could be divided into five stages: Larval-pupal apolysis, cryptocephalic pupa, phanerocephalic pupa, pharate adult, and emergent adult. It lays a morphology-based foundation for molecular mechanism studies and enhances the understanding of the physiological basis for changes in intrapuparial development. More importantly, the chronology of intrapuparial development can be used to predict the emergence time of tephritid flies, indicating when to spray insecticides to control these phytophagous agricultural pests. This may be an effective approach to reduce the use of insecticides and slow down the evolution of insecticidal resistance.
Effects of Prevalent and Incident Atrial Fibrillation on Renal Outcome, Cardiovascular Events, and Mortality in Patients with Chronic Kidney Disease
Authors: Hsu Hsin-Hui , Kor Chew-Teng , Hsieh Yao-Peng , Chiu Ping-Fang
Published: September 2019

Background: Little is known about how incident atrial fibrillation (AF) affects the clinical outcomes in chronic kidney disease (CKD) patients and whether there is a different influence between pre-existing and incident AF. Methods: Incident CKD patients from 2000 to 2013 were retrieved from the National Health Insurance Research Database (NHIRD) of Taiwan and they were classified as non-AF (n = 15,251), prevalent AF (n = 612), and incident AF (n = 588). The outcomes of interest were end-stage renal disease (ESRD) requiring dialysis, all-cause mortality, cardiovascular (CV) mortality, acute myocardial infarction (AMI), stroke or systemic thromboembolism. Results: Compared with CKD patients without AF, those with prevalent or incident AF were associated with higher adjusted rates of ESRD (hazard ratio (HR), 1.40; 95% confidence interval (CI), 1.32–1.48; HR, 2.91; 95% CI, 2.74–3.09, respectively), stroke or systemic thromboembolism (HR, 1.89; 95% CI, 1.77–2.03; HR, 1.67; 95% CI, 1.54–1.81, respectively), AMI (HR, 1.24; 95% CI, 1.09–1.41; HR, 1.99; 95% CI, 1.75–2.27, respectively), all-cause mortality (HR, 1.64; 95% CI, 1.56–1.72; HR, 2.17; 95% CI, 2.06–2.29, respectively), and CV mortality (HR, 2.95; 95% CI, 2.62–3.32; HR, 4.61; 95% CI, 4.09–5.20, respectively). Intriguingly, CKD patients with prevalent AF were associated with lower adjusted rates of ESRD, AMI, all-cause mortality, and CV mortality compared with those with incident AF. Conclusion: Both incident and prevalent AF were independently associated with greater risks of AMI, all-cause mortality, CV mortality, ESRD, and stroke or systemic thromboembolism. Our findings are novel in that, compared with prevalent AF, incident AF possessed an even higher risk of some clinical consequences, including ESRD, all-cause mortality, CV mortality, and AMI.