bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical characteristic of biliary tract dysfunction in children in the Kyrgyz Republic
Authors: Alymbaev E. , Malevannaya V. , Kozhonazarova G.
Published: February 2019

The article presents clinical, laboratory, instrumental data in children with functional biliary dyskinesias. Studies were conducted for the period 2014–2018. on the clinical base of the National Center for Maternal and Child Welfare. The object of the study were 120 children from 7 to 14 years. It has been established that the formation of a symptom complex in most cases is ambiguous and develops against the background of various diseases that were previously experienced. The presence of a large variation in the duration of the disease indicates a delayed diagnosis of pathology. Determining the type of biliary dyskinesia allows you to choose the most effective treatment regimen.
Study of agrochemical and physical-chemical properties gray-brown soils of the Karabakh Plain
Authors: Osmanova S.
Published: February 2019

Research is conducted at the Terter Regional Experimental Station of the Research Institute for Agriculture. In order to improve the fertility of gray-brown soils and obtain high-quality crop yields, we studied the agrochemical and physical–chemical properties of the experimental plot. Thus, the analysis of gray–brown soils showed that, according to the gradation adopted in Azerbaijan, these soils are poorly supplied with nutrients, in an easily digestible form of plants. Therefore, it is necessary to make in these soils together organic and mineral fertilizers.
Retrospective analysis of reproduction processes of fixed capital of railway transport
Authors: Gulamov A.
Published: February 2019

Joint–stock company “Uzbek Railways” is the largest transport company in the country and in some segments of the transport market works in conditions of tough competition. With the development of market relations and economic growth, as well as competitive pressure from other participants in the transport market, reliable condition, efficient use and intensive reproduction of fixed assets are becoming increasingly important. In this regard, the research and development of effective methods of the reproductive process of the railway company. In this article, a retrospective analysis of the reproduction of the fixed capital of a railway company is carried out and suggestions are given for the intensification of this process.
From the Qualities of Products to the Qualities of Relations: Value Conventions in the Solidarity Economy in Sicily
Authors: Varga Mihai
Published: February 2019

This article explores the “quality battlefield” in the food economy – the dispute over value conventions between mainstream business actors and alternative food networks. It shows how actors in one particular alternative network – the solidarity economy – shift such notions from product qualities to the qualities of relations in production. Opposing the standardized criteria characterizing private certification schemes and organic certification, they struggle to establish the value of their products by creating and circulating verifiable stories proving their involvement in the solidarity economy. These stories further emphasize the distance to standard business motivations, for instance by accentuating the cooperative rather than competitive relations with other producers. The article illustrates the features and tensions of value conventions in alternative food networks by contrasting actors in mainstream agriculture with an expanding organization of agricultural producers adhering to solidarity economy and operating in the grocery sector in Sicily, Italy.
On Inventing the Purpose-Driven Enterprise
Authors: Levillain Kevin , Segestrin Blanche
Published: February 2019

In this article we present the main lineaments for a reform of the business corporation introducing the purpose of the firm. In France, a report commissioned by the government recommends that two new concepts should be introduced in law: the raison d’être of the firm and “purpose-driven enterprises.” This reform partly originated in a research program carried out in France after 2009. The legal articulation of a so-called “purpose-driven enterprise” has now taken off, first in the US and now in France and elsewhere. It paves the way to introducing sustainability issues and new valuations processes in corporate governance.
Fast 3D Semantic Mapping in Road Scenes
Authors: Li Xuanpeng , Wang Dong , Ao Huanxuan , Belaroussi Rachid , Gruyer Dominique
Published: February 2019

Fast 3D reconstruction with semantic information in road scenes is of great requirements for autonomous navigation. It involves issues of geometry and appearance in the field of computer vision. In this work, we propose a fast 3D semantic mapping system based on the monocular vision by fusion of localization, mapping, and scene parsing. From visual sequences, it can estimate the camera pose, calculate the depth, predict the semantic segmentation, and finally realize the 3D semantic mapping. Our system consists of three modules: a parallel visual Simultaneous Localization And Mapping (SLAM) and semantic segmentation module, an incrementally semantic transfer from 2D image to 3D point cloud, and a global optimization based on Conditional Random Field (CRF). It is a heuristic approach that improves the accuracy of the 3D semantic labeling in light of the spatial consistency on each step of 3D reconstruction. In our framework, there is no need to make semantic inference on each frame of sequence, since the 3D point cloud data with semantic information is corresponding to sparse reference frames. It saves on the computational cost and allows our mapping system to perform online. We evaluate the system on road scenes, e.g., KITTI, and observe a significant speed-up in the inference stage by labeling on the 3D point cloud.
Design of a Liquid-Crystal-Tunable Terahertz Demultiplexer Based on a Metal-Insulator-Metal Waveguide
Authors: Li Xue-Shi , Feng Naixing , Xu Yuan-Mei , Cheng Liang-Lun , Liu Qing Huo
Published: February 2019

A tunable demultiplexer with three output channels infiltrated by liquid crystal (LC) is presented, which is based on a metal-insulator-metal (MIM) waveguide. The operating frequencies of the three output channels can be tuned simultaneously at will by changing the external bias electric field applied to the LC. By analyzing the Fabry-Pérot (FP) resonance modes of the finite-length MIM waveguide both theoretically and numerically, the locations of the three channels are delicately determined to achieve the best demultiplexing effects. Terahertz (THz) signals input from the main channel can be demultiplexed by channels 1, 2 and 3 at 0.7135 THz, 1.068 THz and 1.429 THz, respectively. By applying an external electric field to alter the tilt angle of the infiltrating LC material, the operating frequencies of channels 1, 2 and 3 can be relatively shifted up to 12.3%, 9.6% and 9.7%, respectively. The designed demultiplexer can not only provide a flexible means to demultiplex signals but also tune operating bands of output channels at the same time.
Aerodynamics from Cursorial Running to Aerial Gliding for Avian Flight Evolution
Authors: Shahid Farzeen , Zhao Jingshan , Godefroit Pascal
Published: February 2019

Among the different models that have been proposed to explain the origin of avian flightfrom terrestrial predators, the cursorial and arboreal hypotheses remain the most discussed.However, the fossil data at hand show that, taken separately, both theories have significantlimitations in explaining the origin of flight in bird lineage. Here, we describe an aerodynamicsprinciple that fills in the gaps between those apparently contradictory models. The upslope wind inmountain areas and strong wind in plains provided the meteorological conditions allowingfeathered paravians to glide. The results suggest that smaller, feathered paravians could be lifted toglide down to trees on mountain slopes or even to glide up to high trees in plain areas when meetinga strong airflow as they were pursuing a prey or escaping from a predator. The development ofmore aerodynamical limb feathers was a key factor for gliding down the trees because of thedependency of the resultant force on the surface area of a paravian’s body. Later in the evolutionprocess, paravians learned to change the orientation of their wings to gain higher lifts. The proposedprinciple and the results obtained in the present research help to better estimate the aerodynamicbehavior of extinct species and will also help to design an efficient and beneficial system for futureflying robots.
Response Surface Methodology for the Optimisation of Electrochemical Biosensors for Heavy Metals Detection
Authors: De Benedetto Giuseppe Egidio , Di Masi Sabrina , Pennetta Antonio , Malitesta Cosimino
Published: February 2019

Herein, we report the application of a chemometric tool for the optimisation of electrochemical biosensor performances. The experimental design was performed based on the responses of an amperometric biosensor developed for metal ions detection using the flow injection analysis. The electrode preparation and the working conditions were selected as experimental parameters, and thus, were modelled by a response surface methodology (RSM). In particular, enzyme concentration, flow rates, and number of cycles were reported as continuous factors, while the sensitivities of the biosensor (S, µA·mM−1) towards metals, such as Bi3+ and Al3+ were collected as responses and optimised by a central composite design (CCD). Bi3+ and Al3+ inhibition on the Pt/PPD/GOx biosensor response is for the first time reported. The optimal enzyme concentration, scan cycles and flow rate were found to be 50 U·mL−1, 30 and, 0.3 mL·min−1, respectively. Descriptive/predictive performances are discussed: the sensitivities of the optimised biosensor agreed with the experimental design prediction. The responses under the optimised conditions were also tested towards Ni2+ and Ag+ ions. The multivariate approach used in this work allowed us to obtain a wide working range for the biosensor, coupled with a high reproducibility of the response (RSD = 0.72%).
Hypoxia Pathway Proteins in Normal and Malignant Hematopoiesis
Authors: Wielockx Ben , Grinenko Tatyana , Mirtschink Peter , Chavakis Triantafyllos
Published: February 2019

The regulation of oxygen (O2) levels is crucial in embryogenesis and adult life, as O2 controls a multitude of key cellular functions. Low oxygen levels (hypoxia) are relevant for tissue physiology as they are integral to adequate metabolism regulation and cell fate. Hence, the hypoxia response is of utmost importance for cell, organ and organism function and is dependent on the hypoxia-inducible factor (HIF) pathway. HIF pathway activity is strictly regulated by the family of oxygen-sensitive HIF prolyl hydroxylase domain (PHD) proteins. Physiologic hypoxia is a hallmark of the hematopoietic stem cell (HSC) niche in the bone marrow. This niche facilitates HSC quiescence and survival. The present review focuses on current knowledge and the many open questions regarding the impact of PHDs/HIFs and other proteins of the hypoxia pathway on the HSC niche and on normal and malignant hematopoiesis.
The Modern View of B Chromosomes Under the Impact of High Scale Omics Analyses
Authors: Ahmad Syed Farhan , Martins Cesar
Published: February 2019

Supernumerary B chromosomes (Bs) are extra karyotype units in addition to A chromosomes, and are found in some fungi and thousands of animals and plant species. Bs are uniquely characterized due to their non-Mendelian inheritance, and represent one of the best examples of genomic conflict. Over the last decades, their genetic composition, function and evolution have remained an unresolved query, although a few successful attempts have been made to address these phenomena. A classical concept based on cytogenetics and genetics is that Bs are selfish and abundant with DNA repeats and transposons, and in most cases, they do not carry any function. However, recently, the modern quantum development of high scale multi-omics techniques has shifted B research towards a new-born field that we call “B-omics”. We review the recent literature and add novel perspectives to the B research, discussing the role of new technologies to understand the mechanistic perspectives of the molecular evolution and function of Bs. The modern view states that B chromosomes are enriched with genes for many significant biological functions, including but not limited to the interesting set of genes related to cell cycle and chromosome structure. Furthermore, the presence of B chromosomes could favor genomic rearrangements and influence the nuclear environment affecting the function of other chromatin regions. We hypothesize that B chromosomes might play a key function in driving their transmission and maintenance inside the cell, as well as offer an extra genomic compartment for evolution.
Structural and Mechanical Properties of Amorphous Si3N4 Nanoparticles Reinforced Al Matrix Composites Prepared by Microwave Sintering
Authors: Mattli Manohar Reddy , Matli Penchal Reddy , Shakoor Abdul , Amer Mohamed Adel Mohamed
Published: February 2019

The present study focuses on the synthesis and characterization of amorphous silicon nitride (Si3N4) reinforced aluminum matrix nanocomposites through the microwave sintering process. The effect of Si3N4 (0, 1, 2 and 3 wt.%) nanoparticles addition to the microstructure and mechanical properties of the Al-Si3N4 nanocomposites were investigated. The density of Al-Si3N4 nanocomposites increased with increased Si3N4 content, while porosity decreased. X-ray diffraction (XRD) analysis reveals the presence of Si3N4 nanoparticles in Al matrix. Microstructural investigation of the nanocomposites shows the uniform distribution of Si3N4 nanoparticles in the aluminum matrix. Mechanical properties of the composites were found to increase with an increasing volume fraction of amorphous Si3N4 reinforcement particles. Al-Si3N4 nanocomposites exhibits higher hardness, yield strength and enhanced compressive performance than the pure Al matrix. A maximum increase of approximately 72% and 37% in ultimate compressive strength and 0.2% yield strength are achieved. Among the synthesized nanocomposites, Al-3wt.% Si3N4 nanocomposites displayed the maximum hardness (77 ± 2 Hv) and compressive strength (364 ± 2 MPa) with minimum porosity level of 1.1%.
Construction and Optimization of Through-Hole LED Models for Use in Designing Traffic Signboards
Authors: Lee Ted Liang-tai , Chen Yi-Chun
Published: February 2019

A modeling procedure was proposed for the through-hole LEDs commonly used in traffic signs. The measurements from a sample batch of LEDs were performed at several midfield distances to provide a set of representative angular intensity distributions as the target pattern in the modeling process. The flat outer dimensions of the LED were accurately measured while the curvature and refractive index of the packaging dome were roughly estimated. These physical parameters were used to build a preliminary LED model in the Monte Carlo simulation software. The simulated angular intensity distribution at each distance was generated by tracing 20,000,000 rays. The normalized cross correlation (NCC) between the measured and simulated data was calculated to represent the resemblance of the model to the real LED. The roughly estimated parameters were then varied within their physical limits to optimize the NCC value. The possibilities of two parameters having interactions were also considered. The final model has all NCCs above 98.8% between the target and simulated patterns.
Thermodynamics of f(R) Gravity with Disformal Transformation
Authors: Geng Chao-Qiang , Hsu Wei-Cheng , Lu Jhih-Rong , Luo Ling-Wei
Published: February 2019

We study thermodynamics in f ( R ) gravity with the disformal transformation. The transformation applied to the matter Lagrangian has the form of γ μ ν = A ( ϕ , X ) g μ ν + B ( ϕ , X ) ∂ μ ϕ ∂ ν ϕ with the assumption of the Minkowski matter metric γ μ ν = η μ ν , where ϕ is the disformal scalar and X is the corresponding kinetic term of ϕ . We verify the generalized first and second laws of thermodynamics in this disformal type of f ( R ) gravity in the Friedmann-Lemaître-Robertson-Walker (FLRW) universe. In addition, we show that the Hubble parameter contains the disformally induced terms, which define the effectively varying equations of state for matter.
Entropic Approach to the Detection of Crucial Events
Authors: Culbreth Garland , West Bruce J. , Grigolini Paolo
Published: February 2019

In this paper, we establish a clear distinction between two processes yielding anomalous diffusion and 1 / f noise. The first process is called Stationary Fractional Brownian Motion (SFBM) and is characterized by the use of stationary correlation functions. The second process rests on the action of crucial events generating ergodicity breakdown and aging effects. We refer to the latter as Aging Fractional Brownian Motion (AFBM). To settle the confusion between these different forms of Fractional Brownian Motion (FBM) we use an entropic approach properly updated to incorporate the recent advances of biology and psychology sciences on cognition. We show that although the joint action of crucial and non-crucial events may have the effect of making the crucial events virtually invisible, the entropic approach allows us to detect their action. The results of this paper lead us to the conclusion that the communication between the heart and the brain is accomplished by AFBM processes.
A Preliminary Study of the Effect of Bioavailable Fe and Co on the Anaerobic Digestion of Rice Straw
Authors: Mancini Gabriele , Papirio Stefano , Lens Piet N. L. , Esposito Giovanni
Published: February 2019

Rice straw is an abundant and sustainable substrate for anaerobic digestion (AD), but it is often deficient in essential trace elements (TEs) for proper microbial growth and metabolism. A lack of TEs leads to AD imbalances and suboptimal biogas yields. However, the total TE concentration is not a sufficient indicator of the amount of TEs available to the microorganisms. Therefore, this study investigated the degree of bioavailability of iron (Fe) and cobalt (Co) during the AD of rice straw, and correlated it to the biomethane yields and volatile fatty acids (VFAs) produced. When the two TEs were dosed at 205 µg Fe/g TS and 18 µg Co/g TS of rice straw, the biomethane production was approximately 260 mL CH4/g VS, i.e., similar to that obtained when Fe and Co were not added. Despite an increased bioavailable fraction of 23 and 48% for Fe and Co, respectively, after TEs addition, the AD performance was not enhanced. Moreover, VFAs did not exceed 250 mg HAc/L both in the presence and absence of added TEs, confirming no enhancement of the methanogenesis step. Therefore, the bioavailability of Fe and Co was not a limiting factor for the biomethane production at low total VFAs concentration.
Optimal Scheduling of Energy Storage Using A New Priority-Based Smart Grid Control Method
Authors: Galván Luis , Navarro Juan M. , Galván Eduardo , Carrasco Juan M. , Alcántara Andrés
Published: February 2019

This paper presents a method to optimally use an energy storage system (such as a battery) on a microgrid with load and photovoltaic generation. The purpose of the method is to employ the photovoltaic generation and energy storage systems to reduce the main grid bill, which includes an energy cost and a power peak cost. The method predicts the loads and generation power of each day, and then searches for an optimal storage behavior plan for the energy storage system according to these predictions. However, this plan is not followed in an open-loop control structure as in previous publications, but provided to a real-time decision algorithm, which also considers real power measures. This algorithm considers a series of device priorities in addition to the storage plan, which makes it robust enough to comply with unpredicted situations. The whole proposed method is implemented on a real-hardware test bench, with its different steps being distributed between a personal computer and a programmable logic controller according to their time scale. When compared to a different state-of-the-art method, the proposed method is concluded to better adjust the energy storage system usage to the photovoltaic generation and general consumption.
Finite Control Set Model Predictive Control for Parallel Connected Online UPS System under Unbalanced and Nonlinear Loads
Authors: Khan Hussain Sarwar , Aamir Muhammad , Ali Muhammad , Waqar Asad , Ali Syed Umaid , Imtiaz Junaid
Published: February 2019

In this paper, the finite control set model predictive control (FCS–MPC) technique-based controller is proposed for the inverter of the uninterrupted power supply (UPS) system. The proposed controller uses the mathematical model of the system to forecast the response of voltage for each possible switching state for every sampling instant. Following this, the cost function was used to determine the switching state, applied to the next sampling instant. First, the proposed control strategy was implemented for the single inverter of the UPS system. Finally, the droop control strategy was implemented for parallel inverters to guarantee actual power sharing among a multiple-parallel UPS system. To validate the performance of the proposed controller under steady-state conditions and dynamic-transient conditions, extensive simulations were conducted using MATLAB/Simulink. The proposed work shows a low computational burden, good steady state performance, fast transient response, and robust results against parameter disturbances as compared to linear control. The simulation results showed that total harmonic distortion (THD) for the linear load was 0.9% and THD for the nonlinear load was 1.42%.
Modelling Influential Factors of Consumption in Buildings Connected to District Heating Systems
Authors: Maljkovic Danica
Published: February 2019

Assessing the influential factors on measured (or allocated) heat consumption in district heating systems is often limited by the available data. Within a project of modelling consumption in district heating systems in Croatia for the Ministry of Environmental Protection and Environment, an access to a complete billing database of the largest Croatian district heating company was granted. The company supplies approximately 126,400 final consumers (both households and businesses) over 375 km of distribution network. The billing database has 40 vectors in a few million single inputs. In addition to these data, a questionnaire is distributed to the final consumers in several buildings labelled as “model buildings”, gathering behavioural and demographic data of final consumers (such as occupancy, mode of space usage, heat comfort level, age of occupants, etc.). The two sets of data are then merged, and a correlation analysis is performed. Furthermore, a two-step regression analysis is performed based on variables from billing database in the first step, with added behavioural and demographic variables obtained from the questionnaires in the second step. The models from two steps are compared, tested and interpreted. Results of the most influential factors on heat consumption in district heating systems are given and the influence of the behavioural/demographic variables on the prediction accuracy of heating consumption is interpreted.
Exploring the Causes of Power-Converter Failure in Wind Turbines based on Comprehensive Field-Data and Damage Analysis
Authors: Fischer Katharina , Pelka Karoline , Puls Sebastian , Poech Max-Hermann , Mertens Axel , Bartschat Arne , Tegtmeier Bernd , Broer Christian , Wenske Jan
Published: February 2019

Power converters are among the most frequently failing components of wind turbines. Despite their massive economic impact, the actual causes and mechanisms underlying these failures have remained in the dark for many years. In view of this situation, a large consortium of three research institutes and 16 companies, including wind-turbine and component manufacturers, operators and maintenance-service providers has joined forces to identify the main causes and driving factors of the power-converter failures in wind turbines to create a basis for effective remedial measures. The present paper summarizes and discusses the results of this research initiative, which have been achieved through the evaluation of converter-specific failure and operating data of a large and diverse worldwide wind-turbine fleet, field measurements as well as post-mortem investigation of returned converter components. A key conclusion of the work is that the thermal-cycling induced fatigue of bond-chip contacts and die-attach solder, which is a known issue in other fields of power-electronics applications and which has been widely assumed to be the principle damage mechanisms also in wind turbines, is no relevant contributor to the observed converter failures in this application. Instead, the results indicate that environmental factors such as humidity and contamination but also design and quality issues as well as human errors play an important part in the incidence of these failures.
Temperature Disturbance Management in a Heat Exchanger Network for Maximum Energy Recovery Considering Economic Analysis
Authors: Hafizan Ainur Munirah , Klemeš Jiří Jaromír , Wan Alwi Sharifah Rafidah , Abdul Manan Zainuddin , Abd Hamid Mohd Kamaruddin
Published: February 2019

The design of heat exchanger networks (HEN) in the process industry has largely focused on minimisation of operating and capital costs using techniques such as pinch analysis or mathematical modelling. Aspects of operability and flexibility, including issues of disturbances affecting downstream processes during the operation of highly integrated HEN, still need development. This work presents a methodology to manage temperature disturbances in a HEN design to achieve maximum heat recovery, considering the impact of supply temperature fluctuations on utility consumption, heat exchanger sizing, bypass placement and economic performance. Key observations have been made and new heuristics are proposed to guide heat exchanger sizing to consider disturbances and bypass placement for cases above and below the HEN pinch point. Application of the methodology on two case studies shows that the impact of supply temperature fluctuations on downstream heat exchangers can be reduced through instant propagation of the disturbances to heaters or coolers. Where possible, the disturbances have been capitalised upon for additional heat recovery using the pinch analysis plus-minus principle as a guide. Results of the case study show that the HEN with maximum HE area yields economic savings of up to 15% per year relative to the HEN with a nominal HE area.
Adaptive Sliding Mode Control for PMSG Wind Turbine Systems
Authors: Lee Sung-Won , Chun Kwan-Ho
Published: February 2019

In this paper, variable speed PMSG wind turbine systems with unknown system parameters, such as vicious friction coefficient and total inertia, are considered. The errors and variations of wind speed are modeled as a disturbance in mechanical torque. In general, the optimum rotating speed is given based on the MPPT (Maximum Power Point Tracking) algorithm and the designed controller tracks the reference (optimum) rotating speed in spite of these parametric uncertainties and disturbances. In order to have a desired rotor speed, a sliding mode current controller is proposed to have robustly stabilizing torque input. From the robustly stabilizing q-axis current i q , q-axis voltage input u q is obtained. Additionally, the d-axis control input u d is designed to regulate the d-axis current i d . The adaptive estimator, for the total inertia J and the viscous friction coefficient F , is designed by a backstepping control technique. The robust stability of the closed-loop system is shown using a Lyapunov function. The proposed controller is verified via a simulation using MATLAB/Simulink.
Thermal Evolution near Heat-Generating Nuclear Waste Canisters Disposed in Horizontal Drillholes
Authors: Finsterle Stefan , Muller Richard A. , Baltzer Rod , Payer Joe , Rector James W.
Published: February 2019

We consider the disposal of spent nuclear fuel and high-level radioactive waste in horizontal holes drilled into deep, low-permeable geologic formations using directional drilling technology. Residual decay heat emanating from these waste forms leads to temperature increases within the drillhole and the surrounding host rock. The spacing of waste canisters and the configuration of the various barrier components within the horizontal drillhole can be designed such that the maximum temperatures remain below limits that are set for each element of the engineered and natural repository system. We present design calculations that examine the thermal evolution around heat-generating waste for a wide range of material properties and disposal configurations. Moreover, we evaluate alternative layouts of a monitoring system to be part of an in situ heater test that helps determine the thermal properties of the as-built repository system. A data-worth analysis is performed to ensure that sufficient information will be collected during the heater test so that subsequent model predictions of the thermal evolution around horizontal deposition holes will reliably estimate the maximum temperatures in the drillhole. The simulations demonstrate that the proposed drillhole disposal strategy can be flexibly designed to ensure dissipation of the heat generated by decaying nuclear waste. Moreover, an in situ heater test can provide the relevant data needed to develop a reliable prediction model of repository performance under as-built conditions.
Identifying Faulty Feeder for Single-Phase High Impedance Fault in Resonant Grounding Distribution System
Authors: Tang Tao , Huang Chun , Li Zhenxing , Yuan Xiuguang
Published: February 2019

The identification of faulty feeder for single-phase high impedance faults (HIFs), especially in resonant grounding distribution system (RGDS), has always been a challenge, and existing faulty feeder identification techniques for HIFs suffer from some drawbacks. For this problem, the fault transient characteristic of single-phase HIF is analyzed and a faulty feeder identification method for HIF is proposed. The analysis shows that the transient zero-sequence current of each feeder is seen as a linear relationship between bus transient zero-sequence voltage and bus transient zero-sequence voltage derivative, and the coefficients are the reciprocal of transition resistance and feeder own capacitance, respectively, in both the over-damping state and the under-damping state. In order to estimate transition resistance and capacitance of each feeder, a least squares algorithm is utilized. The estimated transition resistance of a healthy feeder is infinite theoretically, and is a huge value practically. However, the estimated transition resistance of faulty feeder is approximately equal to actual fault resistance value, and it is far less than the set threshold. According to the above significant difference, the faulty feeder can be identified. The efficiency of the proposed method for the single-phase HIF in RGDS is verified by simulation results and experimental results that are based on RTDS.
Optimal Economic and Emission Dispatch of a Microgrid with a Combined Heat and Power System
Authors: He Liangce , Lu Zhigang , Pan Lili , Zhao Hao , Li Xueping , Zhang Jiangfeng
Published: February 2019

With the rapid development of the new concept of energy internet, electric power systems often need to be investigated together with thermal energy systems. Additionally, to reduce pollution from gas emissions, it is very important to study the economic and emission dispatch of integrated electrical and heating systems. Hence, this paper proposes a multi-objective optimization dispatch model for a microgrid (MG) with a combined heat and power (CHP) system. This CHP-based MG system consists of a CHP unit, a wind turbine, a PV system, a fuel cell, an electric boiler, an electric storage, and a heat storage. It can exchange electricity with the distribution network and exchange heat with the district heating network. Minimum economic cost and minimum environmental cost are considered as the two objectives for the operation of this CHP-based MG system. To solve the two objective optimization problem, the multi-objective bacterial colony chemotaxis algorithm is utilized to obtain the Pareto optimal solution set, and the optimal solution is chosen by the Technique for Order of Preference by Similarity to Ideal Solution method. Finally, numerical case studies demonstrate the effectiveness of proposed model and method for the optimal economic and emission dispatch of the CHP-based MG system.
Analysis of the Peak Load Leveling Mode of a Hybrid Power System with Flywheel Energy Storage in Oil Drilling Rig
Authors: Dai Xingjian , Wei Kunpeng , Zhang Xiaozhang
Published: February 2019

The load frequently oscillates in large amplitude like pulses when the draw-works lift or lower in the oil well drilling rig, and that makes the diesel engine run uneconomically. A new solution for the pulse load problem is to add a motor/generator set and a flywheel energy storage (FES) unit to the diesel engine mechanical drive system to form a hybrid power system with energy storage. The storage capacity of the power and energy, and the charging-discharging operation modes are discussed for the first time. The engine power output in frequent fluctuation was measured in the oil well drilling engineering practice. The configuration and the theoretical model of the hybrid power system with energy storage and peak load leveling were established. Furthermore, 1% to 12% saving of fuel is possible for the case of single engine in the load leveling running mode compared to bi-engines in a traditional running mode for the peak load between 900 to 1200 kW and the valley load between 200 to 600 kW. The experimental verification of the load leveling with FES confirmed that the diesel engine worked more smoothly with less smoke emission. In addition, 5% to 10% more fuel was consumed in the load leveling test compared to the traditional running mode with the drive-by 800 kW diesel engine. However, 21% fuel saving was obtained in the load leveling test with the drive-by 400 kW diesel generator.
Short-Term Effects of Different Forest Management Methods on Soil Microbial Communities of a Natural Quercus aliena var. acuteserrata Forest in Xiaolongshan, China
Authors: Wan Pan , Zhang Gongqiao , Zhao Zhonghua , Hu Yanbo , Liu Wenzhen , Hui Gangying
Published: February 2019

One of the aims of sustainable forest management is to preserve the diversity and resilience of ecosystems. Unfortunately, changes in the soil microbial communities after forest management remain unclear. We analyzed and compared the soil microbial community of a natural Quercus aliena var. acuteserrata forest after four years of four different management methods using high-throughput sequencing technology. The forest management methods were close-to-nature management (CNFM), structure-based forest management (SBFM), secondary forest comprehensive silviculture (SFCS) and unmanaged control (CK). The results showed that: (1) the soil microbial community diversity indices were not significantly different among the different management methods. (2) The relative abundance of Proteobacteria in the SBFM treatment was lower than in the CK treatment, while the relative abundance of Acidobacteria in the SBFM was significantly higher than that in the CK treatment. The relative abundance of Ascomycota was highest in the CNFM treatment, and that of Basidiomycota was lowest in the CNFM treatment. However, the relative abundance of dominant bacterial and fungal phyla was not significantly different in CK and SFCS. (3) Redundancy analysis (RDA) showed that the soil organic matter (SOM), total nitrogen (TN), and available nitrogen (AN) significantly correlated with the bacterial communities, and the available potassium (AK) was the only soil nutrient, which significantly correlated with the composition of the fungal communities. The short-term SBFM treatment altered microbial bacterial community compositions, which may be attributed to the phyla present (e.g., Proteobacteria and Acidobacteria), and the short-term CNFM treatment altered microbial fungal community compositions, which may be attributed to the phyla present (e.g., Ascomycota and Basidiomycota). Furthermore, soil nutrients could affect the dominant soil microbial communities, and its influence was greater on the bacterial community than on the fungal community.
An Integrative Systems Perspective on Plant Phosphate Research
Authors: Ajmera Ishan , Hodgman T. Charlie , Lu Chungui
Published: February 2019

The case for improving crop phosphorus-use-efficiency is widely recognized. Although much is known about the molecular and regulatory mechanisms, improvements have been hampered by the extreme complexity of phosphorus (P) dynamics, which involves soil chemistry; plant-soil interactions; uptake, transport, utilization and remobilization within plants; and agricultural practices. The urgency and direction of phosphate research is also dependent upon the finite sources of P, availability of stocks to farmers and reducing environmental hazards. This work introduces integrative systems approaches as a way to represent and understand this complexity, so that meaningful links can be established between genotype, environment, crop traits and yield. It aims to provide a large set of pointers to potential genes and research practice, with a view to encouraging members of the plant-phosphate research community to adopt such approaches so that, together, we can aid efforts in global food security.
A Pilot Study to Investigate the Balance between Proteases and α1-Antitrypsin in Bronchoalveolar Lavage Fluid of Lung Transplant Recipients
Authors: Cagnone Maddalena , Piloni Davide , Ferrarotti Ilaria , Di Venere Monica , Viglio Simona , Magni Sara , Bardoni Anna , Salvini Roberta , Fumagalli Marco , Iadarola Paolo , Martinello Sabrina , Meloni Federica
Published: February 2019

The neutrophilic component in bronchiolitis obliterans syndrome (BOS, the main form of chronic lung rejection), plays a crucial role in the pathogenesis and maintenance of the disorder. Human Neutrophil Elastase (HNE), a serine protease responsible of elastin degradation whose action is counteracted by α1-antitrypsin (AAT), a serum inhibitor specific for this protease. This work aimed to investigate the relationship between HNE and AAT in bronchoalveolar lavage fluid (BALf) from stable lung transplant recipients and BOS patients to understand whether the imbalance between proteases and inhibitors is relevant to the development of BOS. To reach this goal a multidisciplinary procedure was applied which included: (i) the use of electrophoresis/western blotting coupled with liquid chromatography-mass spectrometric analysis; (ii) the functional evaluation of the residual antiprotease activity, and (iii) a neutrophil count. The results of these experiments demonstrated, for the first time, the presence of the complex between HNE and AAT in a number of BALf samples. The lack of this complex in a few specimens analyzed was investigated in relation to a patient’s lung inflammation. The neutrophil count and the determination of HNE and AAT activities allowed us to speculate that the presence of the complex correlated with the level of lung inflammation.
Age-Related Differences in miRNA Expression in Mexican-American Newborns and Children
Authors: Huen Karen , Lizarraga Daneida , Kogut Katherine , Eskenazi Brenda , Holland Nina
Published: February 2019

Epigenetic mechanisms have emerged as an important pathway through which environmental exposures can affect health through the regulation of gene expression without changes in DNA sequence: microRNAs (miRNAs) are short non-coding RNAs that target protein-coding mRNAs, leading to post-transcriptional repression. They are involved in important physiologic processes, but little is known about how miRNA expression may change with age in children. We used an nCounter miRNA assay to assess the expression of 43 miRNAs in buffy coat samples collected from newborns (n = 121) and 7-year-old (n = 142) children. We identified 36 miRNAs that were differentially expressed between newborns and 7-year-olds after controlling for blood cell composition. Using pathway analysis, we found that differentially expressed miRNAs targeted genes enriched for processes related to post-translational modifications, metabolism, and immune response. Our study found that unlike adults, where miRNA expression levels in peripheral blood may decrease with age, expression levels of most miRNAs increased from birth to mid-childhood. This may be reflective of the role miRNAs may play in the highly coordinated mechanisms regulating genes involved in children’s development. Furthermore, it will be important to adjust for both age and blood cell composition in future pediatric studies of miRNA expression in blood.
Phosphorus Concentration in Knee Joint Structures of Patients Following Replacement Surgery
Authors: Żaneta Ciosek , Danuta Kosik-Bogacka , Natalia Łanocha-Arendarczyk , Karolina Kot , Maciej Karaczun , Paweł Ziętek , Patrycja Kupnicka , Aleksandra Szylińska , Mateusz Bosiacki , Iwona Rotter
Published: February 2019

The aim of the study was to assess phosphorus (P) concentration in structures of the knee joint—including the tibial spongy bone, articular cartilage, meniscus, anterior cruciate ligament, and infrapatellar fat pad (Hoffa’s fat pad)—of patients following knee joint replacement. The study also aimed to assess the influence of selected biological and environmental factors on P concentration in studied parts of the knee joint. Phosphorus concentration was determined using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Statistically significant differences in P concentration were found between different elements of the knee joint. The highest P concentration was measured in the spongy bone (72,746.68 mg kg−1 dw) and the lowest in the Hoffa’s fat pad (1203.19 mg kg−1 dw). P levels were unaffected by gender, age, BMI, place of residence, smoking, or alcohol consumption. Data on P concentration in the osteoarticular elements of the knee may be useful in the interpretation and evaluation of biochemical, morphological, and mechanical changes occurring in the body.
The Relationship between Socioeconomic Status, Mental Health, and Need for Long-Term Services and Supports among the Chinese Elderly in Shandong Province—A Cross-Sectional Study
Authors: Kong Fanlei , Xu Lingzhong , Kong Mei , Li Shixue , Zhou Chengchao , Li Jiajia , Sun Long , Qin Wenzhe
Published: February 2019

This study aims to clarify the association between socioeconomic status (SES), mental health, and the need for long-term services and support (NLTSS) of the Chinese elderly, and further, to provide evidence-based suggestions for the development of the long-term services and support (LTSS) system in China. A cross-sectional survey using a multi-stage random sampling method was conducted in Shandong Province, China, in 2017. Data were collected from seniors aged over 60 years old through questionnaires by face-to face interviews. A total of 7070 subjects were included in the final database (40.3% male and 59.7% female). A chi-square test analysis and structural equation modeling (SEM) were employed to explore the relationship between SES, mental health, and NLTSS for both male and female elderly people. The SEM analysis showed that mental health was significantly and negatively associated with NLTSS for both male elderly and female elderly, and it was slightly stronger among the male elderly. A significant and negative relationship was observed between SES and NLTSS for both genders, and the association was stronger among the female elderly. SES exerted a positive effect on mental health for both male and female elderly people, and a slightly stronger effect was found among the male elderly. Advice for the development of a LTSS system in China was given based on the above results.
Effects of Intervention Program Prev@cib on Traditional Bullying and Cyberbullying
Authors: Ortega-Barón Jessica , Buelga Sofía , Ayllón Ester , Martínez-Ferrer Belén , Cava María-Jesús
Published: February 2019

Due to the negative consequences of being bullied and the increase in cyberbullying among adolescents, there is a need for evidence-based programs to prevent and intervene in these types of peer violence. The aim of this study was to evaluate the effectiveness of the Prev@cib bullying and cyberbullying program, drawing on three theoretical frameworks: the ecological model, empowerment theory, and the model of personal and social responsibility. The Prev@cib program was evaluated using a repeated-measures pre-post-test design with an experimental group and a control group. The sample consisted of 660 adolescents between 12 and 17 years old (M = 13.58, SD = 1.26), randomly assigned to the experimental and control groups. Repeated-measures ANOVA of pre-post-test scores were conducted. Results showed a significant decrease in bullying and victimization and cyberbullying and cybervictimization in the experimental group, compared to the control group, indicating that the Prev@cib program is effective in reducing bullying and cyberbullying. Taking into account the harmful effects of these types of violence, the results have important implications in the prevention of these behaviors because they provide scientific evidence of the program’s effectiveness.
Identifying Barriers and Supports to Breastfeeding in the Workplace Experienced by Mothers in the New Hampshire Special Supplemental Nutrition Program for Women, Infants, and Children Utilizing the Total Worker Health Framework
Authors: Lauer Eric A. , Armenti Karla , Henning Margaret , Sirois Lissa
Published: February 2019

Variations in the barriers and contributors to breastfeeding across industries have not been well characterized for vulnerable populations such as mothers participating in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Our study used the Total Worker Health Framework to characterize workplace factors acting as barriers and/or contributors to breastfeeding among women participating in the New Hampshire WIC. Surveys were collected from WIC mothers (n = 682), which asked about employment, industry, and workplace accommodation and supports related to breastfeeding in the workplace. We found workplace policy factors supporting breastfeeding (i.e., having paid maternity leave, other maternity leave, and a breastfeeding policy) varied by industry. Women in specific service-oriented industries (i.e., accommodation and retail) reported the lowest rates of breastfeeding initiation and workplace supports for breastfeeding and pumping. Further, how a woman hoped to feed and having a private pumping space at work were significantly associated with industry, breastfeeding initiation, and breastfeeding duration. A substantial portion of women reported being not sure about their workplace environment, policies, and culture related to breastfeeding. Additional studies with larger sample sizes of women participating in WIC are needed to further characterize the barriers to breastfeeding associated with specific industries.