bluuebunny/crossref_metadata_2025 huggingface dataset:
Vascular dysfunction in the stroke-prone spontaneously hypertensive rat is dependent on constrictor prostanoid activity and Y chromosome lineage
Authors: Khan Shanzana I. , Andrews Karen L. , Jefferis Ann-Maree , Jennings Garry L. , Sampson Amanda K. , Chin-Dusting Jaye P.F.
Published: November 2017

Vascular dysfunction is a hallmark of hypertension and the strongest risk factor to date for coronary artery disease. As Y chromosome lineage has emerged as one of the strongest genetic predictors of cardiovascular disease risk to date, we investigated if Y chromosome lineage modulated this important facet in the stroke-prone spontaneously hypertensive rat (SHRSP) using consomic strains. Here, we show that vascular dysfunction in the SHRSP is attributable to differential cyclooxygenase (COX) activity with nitric oxide (NO) levels playing a less significant role. Measurement of prostacyclin, the most abundant product of COX in the vasculature, confirmed the augmented COX activity in the SHRSP aorta. This was accompanied by functional impairment of the vasodilatory prostacyclin (IP) receptor, while inhibition of the thromboxane (TP) receptor significantly ameliorated vascular dysfunction in the SHRSP, suggesting this is the downstream target responsible for constrictor prostanoid activity. Importantly, Y chromosome lineage was shown to modulate vascular function in the SHRSP through influencing COX activity, prostacyclin levels and IP dysfunction. Vascular dysfunction in the renal and intrarenal arteries was also found to be prostanoid and Y chromosome dependent. Interestingly, despite no apparent differences in agonist-stimulated NO levels, basal NO levels were compromised in the SHRSP aorta, which was also Y chromosome dependent. Thus, in contrast with the widely held view that COX inhibition is deleterious for the vasculature due to inhibition of the vasodilator prostacyclin, we show that COX inhibition abolishes vascular dysfunction in three distinct vascular beds, with IP dysfunction likely being a key mechanism underlying this effect. We also delineate a novel role for Y chromosome lineage in regulating vascular function through modulation of COX and basal NO levels.
Efficient information‐theoretic unsupervised feature selection
Authors: Lee J. , Seo W. , Kim D.‐W.
Published: November 2017

The method proposed in this Letter selects a feature subset that preserves the data quality in the viewpoint of information theory. Using an efficient information‐theoretic evaluation, the proposed method identifies the final feature subset significantly faster than conventional methods.
Estimating fluorescence lifetimes using the expectation‐maximisation algorithm
Authors: Gao Kai , Li David Day‐Uei
Published: November 2017

The expectation‐maximisation (EM) algorithm uses incomplete data to get the estimation of the probabilistic model parameter, and it has been widely used in machine learning. EM techniques are applied to estimate fluorescence lifetimes in time‐correlated single‐photon counting based fluorescence lifetime imaging experiments without measuring the instrument response functions. The results of Monte Carlo simulations indicate that the proposed approach can obtain better or comparable accuracy and precision performances than the previously reported method.
DC‐16 GHz GaAs track‐and‐hold amplifier using sampling rate and linearity enhancement techniques
Authors: Lin Y.‐A. , Chang H.‐Y. , Wang Y.‐C.
Published: November 2017

A DC‐16 GHz track‐and‐hold amplifier (THA) using 0.15‐μm enhancement‐mode GaAs pseudomorphic high‐electron mobility transistor process is presented. A switched source follower (SSF) track‐and‐hold (T/H) stage is modified to enhance the sampling rate and linearity. The input‐dependent timing jitter is highly reduced using the modified topology as compared to the conventional SSF T/H stage. Moreover, the even harmonics are successfully suppressed using the differential topology, and the spurious‐free dynamic range (SFDR) and total harmonic distortion (THD) are improved. To widen bandwidth (BW), the input and output buffers are designed using the distributed amplifier and source follower, respectively. With a sampling rate of 13.5 GS/s, the proposed THA features a measured 3‐dB BW of 16 GHz, an SFDR of 46 dB, and a THD of −45 dB.
Variable on‐time controlled boundary conduction mode single‐ended primary inductor converter power factor correction converter
Authors: Shen Xia , Yan Tiesheng , Li Qi , Wang Yingmin , Chen Weirong
Published: November 2017

A variable on‐time (VOT) control strategy for boundary conduction mode (BCM) single‐ended primary inductor converter (SEPIC) power factor correction (PFC) converter with high power factor (PF) and low total harmonic distortion (THD) is proposed. By utilising output voltage and input voltage to modulate the turn‐on time of the switch of BCM SEPIC PFC converter, the unity PF and lower THD can be achieved. The operating principles of the VOT controlled BCM SEPIC PFC converter are analysed. The experimental results based on 100 W prototype demonstrate that the PF and THD of proposed VOT controlled BCM SEPIC PFC converter are better than those of traditional BCM SEPIC PFC converter.
Closed‐form estimators of CGIG distributed parameters
Authors: Mezache A. , Sahed M.
Published: November 2017

The interpolation method has been employed in non‐integer‐order moments estimators obtained in a previous work for the parameters of compound‐Gaussian clutter model with inverse Gaussian texture (CGIG). Closed‐form parameter estimators for the CGIG distributed clutter are derived with no special functions. These are achieved after a simple combination of three basic expressions: non‐integer positive moments, non‐integer negative moments and Bessel recurrence relation. Simulation results show that the derived estimators are well suited for multilook data and have a comparable accuracy as well as the numerically solved maximum‐likelihood approach, but they are much simpler and faster to compute
Improving internal parallelism of solid state drives with selective multi‐plane operation
Authors: Shin I.
Published: November 2017

Solid state drives (SSDs) achieve a significantly better performance than hard disks by internally implementing channel level, chip level, and die level parallelism. However, the plane level parallelism has not been sufficiently exploited, because of the constraint that the target pages of the planes must be in the same location. To overcome this constraint, a policy that enforces the multi‐plane operation by matching the position of the target pages while wasting clean pages is proposed. However, this policy excessively increases the number of block erasures, which leads to reducing the stability and lifetime of the SSD. To solve this problem, this Letter proposes a policy that determines whether to perform the multi‐plane operation considering the number of wasted clean pages. The performance evaluation using representative server workloads shows that the proposed policy improves an average performance by up to 28.82% over the policy that does not perform the multi‐plane operation, without significantly increasing the number of block erasures.
Blind estimation of transmit‐antenna number for non‐Cooperative multiple‐input multiple‐output orthogonal frequency division multiplexing systems
Authors: Li Tao , Li Yongzhao , Cimini Leonard J. , Zhang Hailin
Published: November 2017

In this study, the authors propose a non‐parametric algorithm to implement the estimation of transmit‐antenna number, which is a prerequisite for blind interception process of multiple‐input multiple‐output orthogonal frequency division multiplexing signals in frequency selective fading. Specifically, a series of test statistics are constructed by exploiting the eigenvalues of the sample covariance matrices from each subcarrier, followed by a combination of these test statistics. As a consequence, the number of transmit antennas can be determined after a serial binary hypothesis testing. The theoretical analysis and simulation results verify the rapid convergence and high reliability of the proposed algorithm at a relatively low signal‐to‐noise ratio.
Synchronisation of alpha‐stable levy noise‐based Random Communication System
Authors: Ahmed Areeb , Savaci Ferit Acar
Published: November 2017

In this study, the pilot‐assisted synchronisation method for a random communication system (RCS) has been proposed. The pilot symbol, which has alpha‐stable distribution, has been used to establish synchronisation and to maintain covertness in the RCS. The introduced synchronisation block (SB) consists of fractional lower‐order covariance‐based correlators (FLOCCs), threshold detectors (TDs) and the synchronisation control block. To measure the performance of the proposed SB, the performance criterion, i.e. confidence ratio (CR), has been proposed. The reliability of the proposed SB can be enhanced by altering the CR and the achieved CR by using the FLOCCs and TDs in SB.
Boosting landmark retrieval baseline with burstiness detection
Authors: Wang Mao , Zhao Lili , Ming Yuewei , Zhu En , Yin Jianping
Published: November 2017

In image retrieval, the bag‐of‐visual‐words model‐based approaches combined with
the spatial verification (SP) post‐processing step have achieved considerable
progress. However, in practice, especially for retrieving landmark images, the
authors have observed that this baseline suffers from the problem of burst matches.
This issue is caused by repetitive visual patterns that appear frequently among
images. Local features derived from these burst patterns can redundantly match
others, resulting in many invalid matches that vote over‐estimated similarity scores
for irrelevant images. Essentially, this problem can be mainly attributed to two
reasons, (i) the non‐exclusive matching leads to one‐to‐many matches, (ii) the SP
fails to filter burst matches that are closely located. To tackle this problem, a
burstiness detection approach using geometric and visual word information of local
features is proposed. Firstly, a geometric filtering strategy is employed to remove
matches that are not consistent with global scale variation. Then, the one‐to‐one
matching strategy is applied to detect and eliminate one‐to‐many matches. Finally,
a down‐weighting burstiness strategy is adopted to penalise the voting weight of
burst matches. Experimental results on three public datasets demonstrate that the
proposed approach can achieve a comparable or even better accuracy over other
popular approaches.
Depth features to recognise dyadic interactions
Authors: Keçeli Ali Seydi , Kaya Aydın , Can Ahmet Burak
Published: November 2017

Usage of depth sensors in activity recognition is an emerging technology in human–computer interaction. This study presents an approach to recognise human‐to‐human interactions by using depth information. Both hand‐crafted features and deep features extracted from depth frames are studied. After selecting and ranking strong features with Relieff algorithm, depth frames are assigned to words. Then, interaction sequences are represented as histograms of words and non‐linear input mapping is applied over histogram bins to minimise differences among various subjects. Random forest, K‐nearest neighbour, and support vector machine (SVM) classifiers are trained using these histograms. The final model is tested on SBU and K3HI datasets and compared with the methods in the literature. In the experiments, joint distances, joint angles and spherical coordinates of the joints were the best performing features. The most successful results are obtained with the composite kernel SVM with Relieff and input mapping methods. While Relieff algorithm helps to select and rank the best features in the feature set, input mapping reduces differences among interactions of various actors.
Improved current control scheme with online current distribution and DFA regulation for switched reluctance generator
Authors: Wang Qing , Chen Hao , Dou Yuyu , Abbas Saleem
Published: November 2017

In this study, an improved phase current control scheme (CCS) for switched reluctance generator is developed and evaluated. The objective of proposed CCS is to find the most efficient operating point according to output power command directly and shorten the online tuning process. The CCS is augmented with an online phase current distributing block (OCDB) and a dynamic firing angle regulator (DFAR). In OCDB, phase current is distributed online to minimise copper loss by maximising the average‐torque–ampere ratio. In DFAR, firing angles are processed according to actual phase current and current command. Improvements in current responses by augmenting DFAR are verified by simulations and experiments. In the end, the proposed CCS is employed in an output power controller for practical applications. Experimental results show that the proposed CCS has good dynamic response and finds the most efficient operating point directly.
ANFIS‐based sensor fault‐tolerant control for hybrid grid
Authors: Sowmmiya Uthayakumar , Uma Govindarajan
Published: November 2017

This paper describes an intelligent sensor fault detection and compensation (FDC) scheme for a hybrid grid involving renewable energy (RE) sources with power electronic interfaces. To evaluate the sensor FDC scheme, a wound rotor induction generator (WRIG)‐based wind energy system connected to the hybrid grid is examined. The system employs a WRIG with excitation from DC RE grid via a single, rotor side converter. To analyse the dynamic performance, a decoupled voltage vector control is employed. The sensors involved in the control algorithm may not be ideal and if fault occurs might lead to system collapse. To overcome electrical sensor failure, a robust, intelligent sensor fault control scheme is proposed with ANFIS. A hardware‐free solution with PLL block is proposed for mechanical sensor fault. The ANFIS‐based FDC scheme involves a bank of observers that computes residuals, detects and isolates faults. When fault occurs, the observer output is utilised for the execution of control algorithm thereby avoiding system collapse. The focused system is simulated in MATLAB and experimentally tested with a dSPACE controller for various fault scenarios. The results show the effectiveness of the FDC scheme.
Conditional value at risk‐based stochastic unit commitment considering the uncertainty of wind power generation
Authors: Zhang Yao , Wang Jianxue , Ding Tao , Wang Xifan
Published: November 2017

This study presents a risk‐averse stochastic unit commitment (SUC) model which considers the loss‐of‐load risk caused by wind power uncertainty. The expected cost of loss‐of‐load is usually considered in the conventional scenario‐based SUC model. However, even if the expected risk of loss‐of‐load induced by all wind scenarios is low, the risk induced by some extreme scenarios can be very high. Thus, there is a strong will to better control the risk in these cases with high costs but low probabilities. In this study, the management of loss‐of‐load risk in worst scenarios is addressed by the conditional value‐at‐risk (CVaR). The proposed SUC model is built in a mixed‐integer linear programming formulation and finally solved by a modified Benders decomposition algorithm with two enhancement strategies (Jensen's inequality and multiple cuts generated from all subproblems). Case studies demonstrate that the loss‐of‐load cost in extreme scenarios decreases after the inclusion of CVaR in the proposed SUC model. The proposed model can also provide multiple unit commitment schedules with different levels of loss‐of‐load risk. Using enhancement strategies in Benders decomposition drastically reduces the total number of iterations, verifying the effectiveness of the modified Benders decomposition algorithm.
Task selection for radar resource management in dynamic environments
Authors: Seok Jinwoo , Kabamba Pierre , Girard Anouck
Published: November 2017

A task selection method for multi‐faced static phased array radar resource management in dynamically changing environments using recomposable restricted finite state machines is presented. Restricted finite state machines allow the design of a composed finite state machine with resource limitations by restricting some of the inputs. Recomposable restricted finite state machines allow the state space of a finite state machine to change dynamically, which allows the modelling of a dynamically changing environment. Applying dynamic programming to restricted finite state machines yields optimal policies for a given cost function and applying breadth‐first search or limited breadth‐first search with fixed depth yields suboptimal solutions for the current state. The authors model a task selector for the radar in an overloaded battlefield situation using recomposable restricted finite state machines and obtain a radar resource allocation policy using dynamic programming when the environment changes dynamically and the resources are limited. The suboptimal solution for the current state is obtained using heuristic methods: breadth‐first search, or limited breadth‐first search in the task selector for large‐scale problems. Furthermore, the authors consider distributed architectures for multi‐radar systems with communication channels. The results show that their approach performs well from the standpoints of both computational time and performance.
Optimisation of offshore wind farm collection systems‐based on modified genetic algorithm
Authors: Zhang Yujing , Qiao Ying , Lu Zongxiang , Sun Wentao
Published: November 2017

The capital cost of the collection system that supports a large off shore wind farm constitutes a significant proportion of the total cost of the wind farm. Thus, finding the optimal design of this collection system is an important task. In order to get the appropriate topological structure of collection system of off shore wind farm, a cost model is proposed first. Then, the topology optimisation problem is formulated into a minimum cost spanning tree problem. After that, modified genetic algorithm (GA) is used to solve the problem. The algorithm improves the GA in coding mode and genetic operator. The case study shows that the modified GA is more effective and converges faster.
Look‐up table approaches for TCSC impedance control considering thyristor conduction characteristic
Authors: Yang Yi , Zhu Xiaojun , Gao Lei , Yuan Yubo , Yao Wei
Published: November 2017

Thyristor‐controlled series capacitor (TCSC) characteristic curves of fundamental frequency impedance change with line current considering thyristor conduction characteristic, which results in experimental deviation when using the open‐loop impedance control. To end this, this study derives the TCSC fundamental frequency impedance mathematic model to reveal the theoretical mechanism that fundamental frequency impedance changes with line currents. This study proposes two new look‐up table approaches to mitigate deviation of the least square look‐up table approach using the three‐point quadratic interpolation and linear interpolation algorithms. The proposed methods have been validated via TCSC physical simulation experiments.
Influence of regional load on subsynchronous resonance of wind farm‐series compensated power transmission system
Authors: Chen Xiaowei , Li Yunhong , Liu Hui , Song Wei
Published: November 2017

The problem of subsynchronous resonance (SSR) may be caused by large‐scale wind power transmission through series compensated transmission system.This study discusses the problem of synchronous resonance in Guyuan, Zhangjiakou, and summarises the regularity of the SSR characteristics with the seasons and analyses the reasons.The results show that the regional load has a significant effect on system damping. On this basis, the influence of different load size, load type and different access points for load on SSR characteristics have been analysed, Also typical SSR phenomenon in Guyuan has been reproduced by time‐domain simulation. This study provides a new way to enhance the system damping and reduce the SSR risk from the grid operating point of view.
Modified R–L model‐based protection for VSC‐DC distribution lines
Authors: Jia Ke , Li Meng , Bi Tianshu , Liu Bohan , Li Wei , Yang Qixun
Published: November 2017

An R–L model‐based line protection algorithm is proposed for the voltage source converter (VSC)‐DC distribution systems. Overviews of DC distribution topology and the fault characteristics are investigated. The feasibility of the R–L model for DC distribution networks is analysed. To decrease errors and increase numerical stability, a new variable acquisition method and a new fault distance estimation equation are proposed with the characteristics of VSC‐DC distribution systems. Simulation results on power systems Computer Aided Design/Electromagnetic Transients including DC (PSCAD/EMTDC) verify the feasibility and accuracy of the proposed protection. It is shown that the protection can efficiently distinguish the internal faults with an operation time < 20 ms and error within 1%. For nearby faults, the protection can trip within 8 ms. The proposed protection can meet both the speed and the selectivity requirements with a low sampling frequency and therefore can be a potential option for the industry application.
DG integration capacity analysis under harmonic constraints
Authors: Gao Fei , Song Xiaohui , Li Jianfang , Zhang Yu , Ma Weiqing , Zhang Huiming
Published: November 2017

The harmonics generated by the distributed generation (DG) inverter have great influence on the DG penetration. To obtain high adaptive conclusions in the distribution network, the DG penetration is analysed from two constrains: voltage distortion and current distortion. Taking the medium‐voltage feeder as the object, this study investigates the influence rule of DG and load distribution position on the voltage distortion change rate along the feeder. The formula for calculating the penetration under the worst condition considering the current distortion limit is deduced. Then a validation method is proposed based on the random scenarios and heuristic optimisation to demonstrate the deduction above. The case study shows that the conclusions can be applied in the medium‐voltage feeder to guide the DG integration.
Research on DC‐link voltage stabiliser for voltage source converter as connected to weak grid
Authors: Huang Yunhui , Tang Jinrui , Zhu Guorong , Li Xianqiang , Tang Haiyan , Li Yan
Published: November 2017

This study investigates design and analysis of direct current (DC)‐link voltage stabiliser for voltage source converter (VSC) as connected to weak grid. To begin with, stability mechanism of VSC is investigated with integrated to weak grid. It is found that phase‐locked loop and terminal voltage control perform as a lagging regulation for DC‐link voltage control, decreasing stability of system. According the mechanism, DC‐link voltage stabiliser needs to provide a leading regulation to eliminate the negative effects. Then, scheme, design and effect of DC‐link voltage stabiliser are studied. Design schemes of stabiliser's inner control loops are presented by bode plots and control blocks. Moreover, control parameters of stabiliser are designed with some practical scenario. Furthermore, effects of stabiliser on VSC control system stability are investigated with varied grid strengths and operating points. Analysis results show that DC‐link voltage stabiliser strengthens system damping and improve stability limits. Time‐domain simulation results show DC‐link voltage stability is improved with stabiliser integrated to VSC, verifying effectiveness of design schemes.
Decentralised method for solving multi‐area stochastic dynamic economic dispatch problem
Authors: Zhao Wenmeng , Zhou Baorong , Liu Mingbo , Yao Wenfeng , Lu Siyu , Wang Tong
Published: November 2017

This study discusses the implementation of a decentralised optimisation method for the multi‐area stochastic dynamic economic dispatch (MASDED) of power systems with wind power integrated. Firstly, the volatility of wind power is represented by sampling wind scenarios, and the consensus constraints of tie‐line power flows among the forecast scenario and sampling scenarios are built. Secondly, the multi‐area power system is decomposed into different areas by creating a coordination centre and duplicating boarder variables. Finally, analytical target cascading method is applied to solve the MASDED in a decentralised way. The master problem of the coordination centre, the forecast scenario subproblems, and the sampling scenario subproblems of each area are solved iteratively. In order to increase computation speed, the decentralised deterministic optimisation is implemented before the decentralised stochastic optimisation. The three‐area IEEE reliability test system is tested to demonstrate the effectiveness of the proposed method.
Discovery of a stellar companion to HD 131399A
Authors: Lagrange A.-M. , Keppler M. , Beust H. , Rodet L. , Meunier N. , Lillo-Box J. , Bonnefoy M. , Galland F.
Published: November 2017

Context. The giant exoplanets imaged on wide orbits (≥10 au) around young stars challenge the classical theories of planet formation. The presence of perturbing bodies could have played a role in the dynamical evolution of the planets once formed.

Aims. We aim to search for close companions to HD 131399, a star around which a giant planet has been discovered, at a projected separation of about 80 au. The star also appears to be a member of a wide (320 au) binary system.

Methods. We recorded HARPS high resolution spectra in January 2017.

Results. We find that HD 131399A is probably seen close to pole-on. We discover a low mass star companion that orbits with a period of about 10 days on a misaligned orbit. Even though the companion does not have an impact on the current dynamical evolution of the planet, it could have played a role in its setting and in clearing the circumstellar disk from which the planet may originate.
Non-equilibrium ionization by a periodic electron beam
Authors: Dzifčáková Elena , Dudík Jaroslav
Published: November 2017

Context. Transition region (TR) spectra typically show the Si IV 1402.8 Å line to be enhanced by a factor of 5 or more compared to the neighboring O IV 1401.2 Å, contrary to predictions of ionization equilibrium models and the Maxwellian distribution of particle energies. Non-equilibrium effects in TR spectra are therefore expected.

Aims. To investigate the combination of non-equilibrium ionization and high-energy particles, we apply the model of the periodic electron beam, represented by a κ-distribution that recurs at periods of several seconds, to plasma at chromospheric temperatures of 104 K. This simple model can approximate a burst of energy release involving accelerated particles.

Methods. Instantaneous time-dependent charge states of silicon and oxygen were calculated and used to synthesize the instantaneous and period-averaged spectra of Si IV and O IV.

Results. The electron beam drives the plasma out of equilibrium. At electron densities of Ne = 1010 cm−3, the plasma is out of ionization equilibrium at all times in all cases we considered, while for a higher density of Ne = 1011 cm−3, ionization equilibrium can be reached toward the end of each period, depending on the conditions. In turn, the character of the period-averaged synthetic spectra also depends on the properties of the beam. While the case of κ = 2 results in spectra with strong or even dominant O IV, higher values of κ can approximate a range of observed TR spectra. Spectra similar to typically observed spectra, with the Si IV 1402.8 Å line about a factor 5 higher than O IV 1401.2 Å, are obtained for κ = 3. An even higher value of κ = 5 results in spectra that are exclusively dominated by Si IV, with negligible O IV emission. This is a possible interpretation of the TR spectra of UV (Ellerman) bursts, although an interpretation that requires a density that is 1–3 orders of magnitude lower than for equilibrium estimates.
Corrosion mechanism of carbon brick in the blast furnace hearth by potassium
Authors: Jiao Ke-xin , Zhang Jian-liang , Liu Zheng-jian , Liu Zhuang-zhuang , Deng Yong , Fan Xiaoyue
Published: November 2017

Alkali plays a significant role in the formation of brittle layer of carbon brick in the blast furnace hearth. The brittle layer in a commercial blast furnace hearth was investigated. Large amounts of potassium compounds were found in the brittle layer. Subsequently, the carbon bricks which reacted with potassium in the simulation of blast furnace hearth under different contents of potassium in the brick (0.25, 0.5, 1.0 and 2.0 wt.%) during various reaction times (0.5, 1, 2 and 4 h) were experimentally studied. Finally, the formation mechanism of the brittle layer in carbon brick was clarified. The investigation results show that a large number of cracks are present in the brittle layer. The average potassium content in the brittle layer is 1 wt.%. According to the experimental results, cracks in the carbon brick can be formed by the attack of potassium. The reason for the formation of the brittle layer in the carbon brick is that the liquid potassium permeates into the carbon brick through the pores and cracks, and then reacts with SiO2 and Al2O3 in CO atmosphere. The generated potassium compounds nepheline and leucite lead to the volume expansion and the damage of the carbon brick.
Comparative studies on acid leaching of zinc waste materials
Authors: Rudnik Ewa , Włoch Grzegorz , Szatan Leszek
Published: November 2017

Three industrial waste materials were characterized in terms of their elemental and phase compositions, leaching behaviour in 10% sulfuric acid solution as well as leaching thermal effects. Slag from melting of mixed metallic scrap contained about 50% Zn and 10% Pb. It consisted mainly of various oxides and oxy-chlorides of metals. Zinc spray metallizing dust contained about 77% Zn in form of zinc and/or zinc-iron oxides, zinc metal and Zn-Fe intermetallic. Zinc ash from hot dip galvanizing was a mixture of zinc oxide, metallic zinc and zinc hydroxide chloride and contained about 80% Zn. Dissolution efficiency of zinc from the first material was 80% (independently on the solid to liquid ratio, 50–150 kg/m3), while decrease of the efficacy from 80% to 60% with increased solid to liquid ratio for the two remaining materials was observed. Both increase in the temperature (20 °C to 35 °C) and agitation rate (300 rpm to 900 rpm) did not improve seriously the leaching results. In all cases, transfer of zinc ions to the leachate was accompanied by different levels of solution contamination, depending on the type of the waste. Leaching of the materials was exothermic with the similar reaction heats for two high oxide-type products (slag, zinc ash) and higher values for the spray metallizing dust.
Transition-Metal-Catalyzed Reactions Involving Arynes
Authors: Mhaske Santosh , Dhokale Ranjeet
Published: November 2017

The plethora of transformations attainable by the transition-metal-catalyzed reactions of arynes has found immense contemporary interest in the scientific community. This review highlights the scope and importance of transition-metal-catalyzed aryne reactions in the field of synthetic organic chemistry reported to date. It covers transformations achieved by the combination of arynes and various transition metals, which provide a facile access to a biaryl motif, fused polycyclic aromatic compounds, different novel carbocycles, various heterocycles, and complex natural products.

1 Introduction

2 Insertion of Arynes

3 Annulation of Arynes

4 Cycloaddition of Arynes

5 Multicomponent Reactions of Arynes

6 Miscellaneous Reactions of Arynes

7 Total Synthesis of Natural Products Using Arynes

8 Conclusion
Treatment of Morbidly Adherent Placentation Utilizing a Standardized Multidisciplinary Approach in the Community Hospital–Private Practice Setting
Authors: Mansouri Mahsa , DeStefano Kim , Monks Brian , Singh Jasbir , McDonnold Mollie , Morgan Jamison , Hale Richard , Adusumalli Jasvant , Horton Amanda , Haeri Sina
Published: November 2017

Objective Morbidly adherent placentation is associated with increased maternal morbidity and mortality. Recently, there has been mounting evidence supporting the benefits of a standardized multidisciplinary approach at tertiary teaching hospitals. Our objective was to estimate the impact of the implementation of a similar program at a high-volume private community hospital.

Study Design In this retrospective cohort study, we evaluated maternal outcomes in all cases of histopathologically confirmed morbidly adherent placentation since the initiation of our multidisciplinary program (2012–2016). Our data were compared with the previously published outcomes of two large cohorts from tertiary teaching hospitals in Utah and Texas.

Results In the 28 cases included for evaluation, our group's median estimated blood loss, median packed red blood cells transfused, median anesthesia time, median length of stay, or rates of maternal morbidity did not statistically differ from the published data in Utah or Texas.

Conclusion Our data demonstrate the feasibility and utility of a multidisciplinary morbidly adherent placentation program in the private practice/community hospital setting with outcomes similar to those at tertiary teaching hospitals. Implementation of such program may prove beneficial in remote centers, where various factors may prohibit patient travel to a larger center.
Work-Related Musculoskeletal Disorders among Plastic Surgeons: A Systematic Review
Authors: Epstein Sherise , Tran Bao , Capone Avery , Ruan Qing , Lee Bernard , Singhal Dhruv
Published: November 2017

Background To date, no review has been conducted on the growing body of literature describing various work-related musculoskeletal disorders (MSDs), ergonomic hazards, and potential interventions relevant to plastic surgeons. This systematic review sought to (1) define the scope of coverage of this important issue in the peer-reviewed literature; (2) critically assess the evidence; and (3) provide recommendations for future directions.

Methods We conducted a literature search of MEDLINE, Embase, Web of Science, and PubMed from the inception of each database until 2016. All articles reporting on work-related MSDs or ergonomics among plastic surgeons were reviewed, summarized, and assessed for trends.

Results Sixteen articles met our inclusion criteria including five expert opinions, four cross-sectional studies and case reports/series, one review, and six experimental studies. Four articles presented evidence on disease burden. The most commonly described work-related MSD was cervical spine disease, for which one study reported a career prevalence of 24.7% (point prevalence in the general population: 0.1–0.4%); three studies reported 64 cases of surgeon work-related MSD resulting in surgical intervention, decreased productivity, or involuntary early retirement. Eight studies described interventions, most of which aimed to improve the ergonomics of microsurgery.

Conclusion This review found low-level evidence of plastic surgeons' vulnerability to a work-related MSD at times severe enough to end careers. Further investigation is needed to clearly define this important problem in plastic surgery. Specifically, future directions should include more methodologically rigorous epidemiologic studies evaluating disease burden.
Update Opportunistic Infections of the Central Nervous System in Patients with Iatrogenic Immunosuppression
Authors: Arendt Gabriele , Maschke Matthias
Published: November 2017

Opportunistic infections of the central nervous system (CNS) with bacteria, parasites, fungi or viruses due to iatrogenic immunosuppression are of immense importance because of rising numbers of organ transplantations and immunomodulating treatments. Besides transplantation medicine, the most frequently involved medical subspecialties are dermatology (interferons, rituximab, fingolimod, among others), hematology/oncology (rituximab, among others), neurology (beta-interferon, glatiramer acetate, natalizumab, rituximab, teriflunomide, fingolimod, alemtuzumab, daclizumab, among others) and rheumatology (rituximab).

In Europe, typical infections affecting the immunocompromised host are due to herpes viruses and, especially in immunomodulated patients, JC virus (JCV); frequently occurring fungi are Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans. An important parasite is Toxoplasma gondii (TG). Typical bacterial infections of the immunocompromised patient are caused by Nocardia asteroides, Listeria monocytogenes and Mycobacterium tuberculosis.Modern diagnostic and therapeutic procedures will be described.
Somatotrope Pituitary Function in Professional Soccer Players
Authors: Roser Pia , Wehrhahn Tatiana , Krogmann Henry , Riedel Nina , Marshall Robert , Gille Justus , Flitsch Jörg , Aberle Jens
Published: November 2017

Background and objective Soccer is associated with repetitive head trauma, which, as it is known from sports like football and boxing, can result in hypopituitarism. Gonadotropins and GH are the most common pituitary hormones to become deficient. GH deficiency is associated with an increased risk of cardiovascular mortality and has negative influence on body mass index, visceral fat mass, insulin resistance and sensitivity, bone mineral density and inflammatory markers. Therefore the aim of this study was to evaluate the somatotrope pituitary function in professional soccer players.

Research design and methods This clinical study included 15 male, professional soccer players with at least 10 years of professional training. Basal hormonal parameters of the pituitary axis were obtained from the participants. To assess GH-IGF-I axis, glucagon stimulation tests were used. Rise in growth hormone during glucagon test was analyzed and the prevalence of newly diagnosed hormone deficiencies was evaluated.

Results Mean age of all participants was 31±10 years. None of the 15 soccer players had GH deficiency. Mean rising factor of GH after stimulation with glucagon was 100 in all participants. We did not find signs of ACTH, TSH or LH/FSH deficiency in any player.

Conclusions In this small collective of soccer players we did not find playing soccer to be a risk factor for the development of GH-deficiency. According to our data screening for somatotrope deficiency is not necessary. Further investigations in larger cohorts are needed.
Water liquid-vapor interface subjected to various electric fields: A molecular dynamics study
Authors: Nikzad Mohammadreza , Azimian Ahmad Reza , Rezaei Majid , Nikzad Safoora
Published: November 2017

Investigation of the effects of E-fields on the liquid-vapor interface is essential for the study of floating water bridge and wetting phenomena. The present study employs the molecular dynamics method to investigate the effects of parallel and perpendicular E-fields on the water liquid-vapor interface. For this purpose, density distribution, number of hydrogen bonds, molecular orientation, and surface tension are examined to gain a better understanding of the interface structure. Results indicate enhancements in parallel E-field decrease the interface width and number of hydrogen bonds, while the opposite holds true in the case of perpendicular E-fields. Moreover, perpendicular fields disturb the water structure at the interface. Given that water molecules tend to be parallel to the interface plane, it is observed that perpendicular E-fields fail to realign water molecules in the field direction while the parallel ones easily do so. It is also shown that surface tension rises with increasing strength of parallel E-fields, while it reduces in the case of perpendicular E-fields. Enhancement of surface tension in the parallel field direction demonstrates how the floating water bridge forms between the beakers. Finally, it is found that application of external E-fields to the liquid-vapor interface does not lead to uniform changes in surface tension and that the liquid-vapor interfacial tension term in Young’s equation should be calculated near the triple-line of the droplet. This is attributed to the multi-directional nature of the droplet surface, indicating that no constant value can be assigned to a droplet’s surface tension in the presence of large electric fields.
A two-dimensional toy model for geophysical turbulence
Authors: Lindborg Erik , Mohanan Ashwin Vishnu
Published: November 2017

A toy model for large scale geophysical turbulence is constructed by making two modifications of the shallow water model. Unlike the shallow water model, the toy model has a quadratic expression for total energy, which is the sum of Available Potential Energy (APE) and Kinetic Energy (KE). More importantly, in contrast to the shallow water model, the toy model does not produce any shocks. Three numerical simulations with different forcing are presented and compared with the simulation of a full General Circulation Model (GCM). The energy which is injected cascades in a similar way as in the GCM. First, some of the energy is converted from APE to KE at large scales. The wave field then undergoes a forward energy cascade displaying shallow spectra, close to k−5/3, for both APE and KE, while the vortical field either displays a k−3-spectrum or a more shallow spectrum, close to k−5/3, depending on the forcing. In a simulation with medium forcing wave number, some of the energy which is converted from APE to KE undergoes an inverse energy cascade which is produced by nonlinear interactions only involving the rotational component of the velocity field. The inverse energy cascade builds up a vortical field at larger scales than the forcing scale. At these scales, coherent vortices emerge with a strong dominance of anticyclonic vortices. The relevance of the simulation results to the dynamics of the atmosphere is discussed as in possible continuations of the investigation.
Static field-gradient polarizabilities of small atoms and molecules at finite temperature
Authors: Tiihonen Juha , Kylänpää Ilkka , Rantala Tapio T.
Published: November 2017

In this work, we propose new field-free estimators of static field-gradient polarizabilities for finite temperature path-integral Monte Carlo method. Namely, dipole–quadrupole polarizability A, dipole–dipole–quadrupole polarizability B, and quadrupole–quadrupole polarizability C are computed for several up to two-electron systems: H, H−, He, Li+, Be2+, Ps2, PsH, H2+, H2, H3+, and HeH+. We provide complementary data for ground state electronic properties within the adiabatic approximation and demonstrate good agreement with available values in the literature. More importantly, we present fully non-adiabatic results from 50 K to 1600 K, which allow us to analyze and discuss strong thermal coupling and rovibrational effects in total field-gradient polarizabilities. These phenomena are most relevant but clearly overlooked, e.g., in the construction of modern polarizable force field models. However, our main purpose is demonstrating the accuracy and simplicity of our approach in a problem that is generally challenging.
Stability analysis for neutral stochastic differential equation of second order driven by Poisson jumps
Authors: Chadha Alka , Bora Swaroop Nandan
Published: November 2017

This paper studies the existence, uniqueness, and exponential stability in mean square for the mild solution of neutral second order stochastic partial differential equations with infinite delay and Poisson jumps. By utilizing the Banach fixed point theorem, first the existence and uniqueness of the mild solution of neutral second order stochastic differential equations is established. Then, the mean square exponential stability for the mild solution of the stochastic system with Poisson jumps is obtained with the help of an established integral inequality.
New approach promises to smooth out silicon texture characterization in solar cells
Authors: Liebendorfer Adam
Published: November 2017

A novel analytical technique drawing on optical simulations simplifies the silicon characterization process and stands to allow analysis of solar cell structure in seconds.
Multiple health conditions and barriers to healthcare among older Australians: prevalence, reasons and types of barriers
Authors: Temple Jeromey B. , Williams Ruth
Published: November 2017

Accompanying population ageing is an increase in the number of older Australians living with multiple health conditions and disabilities (Australian Institute of Health and Welfare 2014). This study sought to examine the barriers to accessing healthcare faced by older Australians. Utilising the 2014 Australian Bureau of Statistics General Social Survey, it was found that 6% of respondents aged 50 years and over reported experiencing a barrier to accessing healthcare within the previous 12 months. Those with multiple health conditions are at a considerably higher risk of experiencing a barrier to healthcare (21% with four or more disabilities) compared with people with no or fewer health conditions, and this risk persists once wide-ranging control variables are included. Long waiting times or unavailability of appointments (43%) were the main type of barriers to accessing healthcare, followed by cost (23%). Points-of-care barriers experienced included accessing GPs, specialists and hospital sector care. Respondents who experienced a barrier were more likely to have low levels of trust in the healthcare system compared with people who had no experience of barriers to healthcare, and were more likely to have a perception of experiencing discrimination or unfair treatment in a healthcare setting.
Loss of APOBEC1 RNA-editing function in microglia exacerbates age-related CNS pathophysiology
Authors: Cole Daniel C. , Chung Youngcheul , Gagnidze Khatuna , Hajdarovic Kaitlyn H. , Rayon-Estrada Violeta , Harjanto Dewi , Bigio Benedetta , Gal-Toth Judit , Milner Teresa A. , McEwen Bruce S. , Papavasiliou F. Nina , Bulloch Karen
Published: November 2017

Significance

Microglia (MG) play important roles in brain homeostasis and neuronal plasticity, and are recruited by the immune system to orchestrate inflammatory responses to danger signals. We find that, within MG, an RNA-editing function performed by the deaminase APOBEC1 and its obligate cofactor affects protein expression levels necessary for harmonious function within these cells and the cells they support. Genetic inactivation of
Apobec1
leads to dysregulation and resultant age-related neurodegeneration in the central nervous system, characterized by increased inflammation, aberrant myelination, and neuronal and MG lysosomal anomalies, culminating in progressive cognitive and motor decline. These data provide powerful evidence supporting the critical role of APOBEC1-mediated RNA editing in maintaining the balance between the homeostatic and activated immune functions of MG.
Capitalism in Africa: mutating capitalist relations and social formations
Authors: Chitonge Horman
Published: November 2017

This debate examines the question of whether African societies are capitalist or not. The debate is currently taking place on the ROAPE website (www.roape.net), addressing the question of whether African societies have persistently managed to elude the irresistible forces of capitalism.