bluuebunny/crossref_metadata_2025 huggingface dataset:
Interlocked Dithi‐Magnetospheres–Decorated MoS2 Nanosheets as Molecular Sieves and Traps for Heavy Metal Ions
Authors: Samantaray Paresh Kumar , Baloda Sonika , Madras Giridhar , Bose Suryasarathi
Published: March 2019

Water remediation at minimal cost is the need of the day, as freshwater aquifers are declining at an alarming rate. To address this challenge, composite membranes is herein developed using a unique reversible addition–fragmentation chain transfer (RAFT)‐synthesized copolymer as the active surface layer, a commercial reverse osmosis (RO) membrane serving as the support layer, and foamy molybdenum disulfide (MoS2) nanosheets decorated with dithi‐magnetospheres acting as the interlayer. This strategy is adopted because the commercial RO membrane is effective toward desalination but is susceptible to fouling and biofilm. The foamy interlayer MoS2 nanosheets decorated with dithi‐magnetospheres in the composite membranes minimize the additional resistance, both in terms of flow and also facilitate reversible action toward heavy metal removal. Further, the composite membranes exhibit a 7‐log reduction in bacterial colonies for both gram‐positive and gram‐negative strains. A stringent and targeted action is also observed in terms of intracellular reactive oxygen species generation. In addition, excellent reversible antifouling with 98.5% flux retention ratio is observed. The average lead (II) removal at 50 ppm is 95.3% and the average arsenic (III) removal at 50 ppm is observed to be 96%. Thus, these membranes could be the next generation to advance sustainable systems for water remediation.
MoS2‐Coupled Carbon Nanosheets Encapsulated on Sodium Titanate Nanowires as Super‐Durable Anode Material for Sodium‐Ion Batteries
Authors: Wang Shitong , Cao Fangjun , Li Yutong , Zhang Zhongtai , Zhou Daming , Yang Yong , Tang Zilong
Published: March 2019

There is an ever‐increasing demand for rechargeable batteries with fast charging, long cycling, high safety, and low cost in new energy storage systems. Herein, a heterogeneous architecture composed of MoS2‐coupled carbon nanosheets encapsulated on sodium titanate nanowires is developed and demonstrated as an advanced anode for sodium‐ion batteries (SIBs). Owing to the synergistic effects of ultrastable substrate of 1D sodium titanate (NTO) nanowires, high‐capacity promoter of 2D MoS2 nanosheets as well as the 2D conductive carbon matrix, the resulting 1D/2D–2D hybrid demonstrates excellent high‐rate capacity and super‐durable cyclability, delivering a stable capacity of up to 425.5 mAh g−1 at 200 mA g−1. Even at an ultrafast charging/discharging process within 80 s, the capacity can be maintained at 201 mAh g−1 after 16 000 cycles with only 0.0012% capacity loss per cycle, one of the best high‐rate capacities and cyclabilities for NTO‐based hybrid composites. The present work highlights the designing protocol of hierarchical nanoarchitectures with stable substrate and high‐capacity electrodes for next‐generation energy storage applications.
Structure‐Activity Relationship of Defective Metal‐Based Photocatalysts for Water Splitting: Experimental and Theoretical Perspectives
Authors: Zhang Yong‐Chao , Afzal Nisha , Pan Lun , Zhang Xiangwen , Zou Ji‐Jun
Published: March 2019

Photocatalytic water splitting is promising for hydrogen energy production using solar energy and developing highly efficient photocatalysts is challenging. Defect engineering is proved to be a very useful strategy to promote the photocatalytic performance of metal‐based photocatalysts, however, the vital role of defects is still ambiguous. This work comprehensively reviews point defective metal‐based photocatalysts for water splitting, focusing on understanding the defects' disorder effect on optical adsorption, charge separation and migration, and surface reaction. The controllable synthesis and tuning strategies of defective structure to improve the photocatalytic performance are summarized, then the characterization techniques and density functional theory calculations are discussed to unveil the defect structure, and analyze the defects induced electronic structure change of catalysts and its ultimate effect on the photocatalytic activity at the molecular level. Finally, the challenge in developing more efficient defective metal‐based photocatalysts is outlined. This work may help further the understanding of the fundamental role of defect structure in the photocatalytic reaction process and guide the rational design and fabrication of highly efficient and low‐cost photocatalysts.
Isolation of a Diylide‐Stabilized Stannylene and Germylene: Enhanced Donor Strength through Coplanar Lone Pair Alignment
Authors: Mohapatra Chandrajeet , Scharf Lennart T. , Scherpf Thorsten , Mallick Bert , Feichtner Kai‐Stephan , Schwarz Christopher , Gessner Viktoria H.
Published: March 2019

The preparation of the first stable diylide‐substituted stannylene and germylene (Y2E, with E=Ge, Sn and Y=[PPh3‐C‐SO2Tol]−) is reported. The synthesis is easily accomplished in one step from the sulfonyl‐substituted metalated ylide YNa and the corresponding ECl2 precursors. Y2Ge and Y2Sn exhibit unusual structures in the solid state and in solution, in which the three adjacent lone pairs in the C‐E‐C linkage are arranged coplanar to each other. As shown by DFT studies, this bonding situation is preferred over the typical π‐donation from the ligands into the empty p‐orbital at the metal due to the strong anion‐stabilizing ability of the sulfonyl groups in the ylide backbone and their additional coordination to the metal. The alignment of the three lone pairs leads to a remarkable boost of the HOMO energy and thus of the donor strengths of the tetrylenes. Hence, Y2Ge and Y2Sn become stronger donors than their diamino or diaryl congeners and comparable to cyclic alkyl(amino)carbenes. First reactivity studies confirm the high reactivity of Y2Ge and Y2Sn, which for example undergo an intramolecular C−H activation reaction via metal–ligand cooperation.
Novel polyhydrazides and polyoxadiazoles based on 1,3,4‐thiadiazole moiety in the main chain with high thermal stability, good solubility, and notable antimicrobial activity
Authors: Aly Kamal I. , Younis Osama , Al‐Muaikel Nayef S. , Atalla Ahmed A. , El‐Adasy Abu‐Bakr A. A. M. , Abdellah Ahmed R.
Published: March 2019

Polyoxadiazoles (PODs) and polyhydrazides (PHs) have wide potential applications; however, PODs are normally insoluble in organic solvents, do not melt, and do not express glass‐transition temperature (Tg), and also PHs do not have high‐temperature resistance. In this work, novel PHs based on 1,3,4‐thiadiazole in the polymer main chain were synthesized by low‐temperature polycondensation. New PODs were then obtained by cyclodehydration of the PHs. The thermal behavior, surface morphology, and crystalline structure were studied using differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and X‐ray diffraction. In addition, the viscosity, solubility, UV–visible absorption, and antimicrobial activity were examined. The new polymers showed melting, Tg, high thermal stability, good solubility in polar aprotic solvents, and significant antimicrobial activities. The enhanced solubility may be attributed to the ability of thiadiazole moiety to form hydrogen bonding with the solvent molecules. Also, it can be concluded that introducing 1,3,4‐thiadiazole and other bulky moieties like the oxadiazole ring into the polymer main chain encouraged more free volumes and weakened the chains packing; hence, the solubility was enhanced and Tg decreased without affecting the thermal stability. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47770.
Confucian Ethics on the Commercial Use of Human Bodies and Body Parts: Yi (Righteousness) or/and Li (Profit)?
Authors: Nie Jing‐Bao , Jones David Gareth
Published: March 2019

In China as elsewhere in the world, human bodies and body parts have long been used for a wide range of medical and non‐medical purposes. In recent decades, China has played a considerable role in some of the public exhibitions of plastinated bodies and body parts, and the commercial trade in organ donations. These contemporary developments have raised numerous challenging ethical and governance questions. In spite of the growing role of China in these, there have been few studies devoted to Chinese ethical thinking that might govern its policies on the use of human bodies and body parts, and in particular on the issue of commercialization. The present study is an attempt to bridge this gap, and concludes that Confucian thinking stresses the primacy of righteousness over profits and utilities. This conclusion is reached directly by drawing on Confucian ethical responses to the peculiar practice of using human body parts, such as placenta and flesh, as drugs in traditional Chinese medicine in imperial China and what has been called “yili zhibian,” the major Confucian discourse on yi (righteousness or justice) and li (profit or interest) in its long history. The principle of prioritizing righteousness over profit leads to a general moral opposition to the commodification of human bodies and body parts. While Confucianism may not place an absolute prohibition on any such use, it does require that any commercial uses are made subject to the fundamental moral principles, such as righteousness, as well as adequate ethical governance procedures.
Improving question retrieval in community question answering service using dependency relations and question classification
Authors: Bae Kyoungman , Ko Youngjoong
Published: March 2019

To build an effective community question answering (cQA) service, determining ways to obtain questions similar to an input query question is a significant research issue. The major challenges for question retrieval in cQA are related to solving the lexical gap problem and estimating the relevance between questions. In this study, we first solve the lexical gap problem using a translation‐based language model (TRLM). Thereafter, we determine features and methods that are competent for estimating the relevance between two questions. For this purpose, we explore ways to use the results of a dependency parser and question classification for category information. Head‐dependent pairs are first extracted as bigram features, called dependency bigrams, from the analysis results of the dependency parser. The probability of each category is estimated using thesoftmaxapproach based on the scores of the classification results. Subsequently, we propose two retrieval models—the dependency‐based model (DM) and category‐based model (CM)—and they are applied to the previous model, TRLM. The experimental results demonstrate that the proposed methods significantly improve the performance of question retrieval in cQA services.
Sensitivity of afternoon precipitation to evaporative fraction in eastern Asia based on ERA‐Interim datasets
Authors: Zhang Shuwen , Yang Xixi , Zhang Weidong , Li Shaoying , Zhang Yuanyuan
Published: March 2019

Sensitivity of afternoon precipitation to before‐noon evaporative fraction (EF) in eastern Asia is investigated by applying two physically based, objective metrics (i.e., triggering feedback strength [TFS] and amplification feedback strength [AFS]) with the ERA‐Interim datasets. Over the northern Indian Peninsula, the Mongolian Plateau and Myanmar, increased before‐noon EF will trigger afternoon precipitation most likely. On the contrary, over south China and Indo‐China peninsula, decreased EF may enhance the occurrence probability of afternoon rainfall. Based on the normalized values of two metrics, the triggering effect of EF is much larger than its amplification effect on afternoon precipitation, and the amplification effect is very small.
Multivariate asset‐pricing model based on subordinated stable processes
Authors: Panov Vladimir , Samarin Evgenii
Published: March 2019

In this paper, we consider a multidimensional time‐changed stochastic process in the context of asset‐pricing modeling. The proposed model is constructed from stable processes, and its construction is based on two popular concepts: multivariate subordination and Lévy copulas. From a theoretical point of view, our main result is Theorem 1, which yields a simulation method from the considered class of processes. Our empirical study shows that the model represents the correlation between asset returns quite well. Moreover, we provide some evidence that this model is more appropriate for describing stock prices than classical time‐changed Brownian motion, at least if the cumulative amount of transactions is used for a stochastic time change.
On the connection between radiative outbursts and timing irregularities in magnetars
Authors: Hu C.‐P. , Ng C.‐Y.
Published: March 2019

Magnetars are strongly magnetized pulsars and they occasionally show violent radiative outbursts. They also often exhibit glitches that are sudden changes in the spin frequency. It was found that some glitches were associated with outbursts but their connection remains unclear. We present a systematic study to identify possible correlations between them. We find that the glitch size of magnetars likely shows a bimodal distribution, different from the distribution of the Vela‐like recurrent glitches but consistent with the high‐end of that of normal pulsars. A glitch is likely a necessary condition for an outburst but not a sufficient condition because only 30% of glitches were associated with outbursts. In the outburst cases, the glitches tend to induce larger frequency changes compared to those unassociated ones. We argue that a larger glitch is more likely to trigger the outburst mechanism, either by reconfiguration of the magnetosphere or deformation of the crust. A more frequent and deeper monitoring of magnetars is necessary for further investigation of their connection.
Predictors of hepatocellular carcinoma recurrence associated with the use of direct‐acting antiviral agent therapy for hepatitis C virus after curative treatment: A prospective multicenter cohort study
Authors: Nakano Masahito , Koga Hironori , Ide Tatsuya , Kuromatsu Ryoko , Hashimoto Satoru , Yatsuhashi Hiroshi , Seike Masataka , Higuchi Nobito , Nakamuta Makoto , Shakado Satoshi , Sakisaka Shotaro , Miuma Satoshi , Nakao Kazuhiko , Yoshimaru Yoko , Sasaki Yutaka , Oeda Satoshi , Eguchi Yuichiro , Honma Yuichi , Harada Masaru , Nagata Kenji , Mawatari Seiichi , Ido Akio , Maeshiro Tatsuji , Matsumoto Shuichi , Takami Yuko , Sohda Tetsuo , Torimura Takuji
Published: March 2019

Background

Previous studies have suggested an association between the use of direct‐acting antiviral agents (DAAs) for treating hepatitis C virus (HCV) infection and the resulting decrease in the incidence of hepatocellular carcinoma (HCC); however, it is unclear whether DAAs prevent the recurrence of HCC after curative treatment for HCC. This study aimed to prospectively investigate HCC recurrence and its predictors after curative treatment for HCC.

Methods

A total of 3012 patients with chronic HCV infection, with or without cirrhosis, who were treated with DAAs were enrolled between January 1, 2015 and January 31, 2017 as per the institutional review board approved study protocol at 15 institutions, including 10 university hospitals and five high‐volume centers in the Kyusyu area of Japan. Of the 3012 patients, 459 patients who had HCC but were cured with surgery or ablation therapy (curative treatment) before the use of DAAs were included in the analysis.

Results

During a mean follow‐up period of 29.4 months, 217 (47.2%) patients developed HCC recurrence. The median time to recurrence was 34.0 months, and the 1‐, 2‐, and 3‐year cumulative HCC recurrence rates were 27.1%, 43.4%, and 50.8%, respectively. The risk factors for HCC recurrence were the α‐fetoprotein (AFP) level before DAA therapy (P = 0.0047) and the number of curative treatments for HCC before DAA therapy (P < 0.0001).

Conclusions

A high AFP level and multiple occurrences of HCC before DAA therapy are associated with a high risk for HCC recurrence after curative treatment. Follow‐up after DAA therapy should include special attention to the abovementioned risk factors.
From Boron Organic Polymers to in situ Ultrafine Nano Pd and Pt: Green Synthesis and Application for High Efficiency Hydrogen Evolution
Authors: Zhao Xue , Fu Yunfan , Yao Chen , Xu Shuran , Shen Yu , Ding Qiong , Liu Wenjing , Zhang Haibo , Zhou Xiaohai
Published: March 2019

Using in situ reduction strategy by combining organic frameworks and ultrafine Pd and Pt nanoparticles (Pd−NPs and Pt−NPs) to synthesize composites with tunable morphology and high dispersion has attracted extensive attentions in fabrication of composite nanomaterials. Herein, on the new kind of substrate, BOPs@Pd and BOPs@Pt nano materials have been successfully fabricated via in situ reduction of Na2PdCl4 and H2PtCl6 triggered by reducibility of organic boron polymers (BOPs). The final products are obtained by loading Pd−NPs and Pt−NPs with ultra‐small size and high dispersion without any tedious chemical modification or additional additives. These materials show high catalytic activity and recyclability in the hydrolysis dehydrogenation of ammonia borane (AB).
Polysulfide Trapping in Carbon Nanofiber Cloth/S Cathode with a Bifunctional Separator for High‐Performance Li–S Batteries
Authors: Ren Wenchen , Ma Wei , Jin Xin , Zhang Shufen , Tang Bingtao
Published: March 2019

The development of carbon nanofiber (CNF) cloth‐based cathodes is essential for the fabrication of high energy density and flexible Li–S batteries. Surface modification is generally used to improve the electrochemical performance of CNF cloth/S cathodes. However, this strategy creates some problems such as structure collapse, complex fabrication steps, and poor consistency. Herein, a β‐MnO2 nanowire/graphene‐modified separator is used to improve the performance of CNF cloth/S cathodes without changing their structure. β‐MnO2 can facilitate chemical bonding with polysulfides, whereas graphene can decrease the inner resistance and trap polysulfide by physical shielding. The cathode with the bifunctional separator displayed a high discharge capacity of 529.9 mAh g−1 with a low capacity decay of 0.051 % per cycle after 500 cycles at 1 C, which is 3 times higher compared with a bare separator. Even with a high sulfur loading of 9.0 mg cm−2, a high areal capacity of 3.8 mAh cm−2 was delivered over 100 cycles.
Improving energy efficiency in information‐centric mobile ad‐hoc networks using places of interest while respecting privacy
Authors: Sepahkar Mehdi , Khayyambashi Mohammad Reza
Published: March 2019

The fact that network users mostly look for content regardless of its location has led to the creation of information‐centric networks with NDN (named data networking project) as the most famous instance. NDN can be implemented in any type of network including MANET (mobile ad‐hoc network) which can be easily created among a collection of smartphones. The first step for content retrieval in NDN is propagating interest packets which has a dramatic effect on energy consumption because of wireless communications. Methods have been devised for limiting the amount of packet propagation. But they are not appropriate for smartphones either because they require multiple WiFi interfaces which is not available in usual smartphones or because they require the exact position of nodes which conflicts privacy. In our proposed approach, a single WiFi interface is used, and mobile nodes will share only an imprecise version of their current and their predicted next location, which complies much better with privacy. Using this information, the amount of interest and data packets will decrease of more than 15%. When location information is spread through the network, this reduction will be almost doubled.
Prevalence of diabetes in liver cirrhosis: A systematic review and meta‐analysis
Authors: Lee Wai Gin , Wells Cameron I. , McCall John L. , Murphy Rinki , Plank Lindsay D.
Published: March 2019

An association between diabetes mellitus (DM) and liver cirrhosis is well‐known, but estimates of the prevalence of DM in patients with liver cirrhosis vary widely. A systematic review was undertaken to determine the prevalence of DM in adult patients with liver cirrhosis. The Medline, EMBASE, and Cochrane Library databases were searched for peer‐reviewed studies published in English (1979‐2017) that investigated the prevalence of diabetes in adult patients with cirrhosis. Pooled estimates of prevalence of DM were determined for all eligible patients and according to aetiology and severity of liver disease. Fifty‐eight studies satisfied criteria for inclusion, with 9705 patients included in the pooled prevalence analysis. The overall prevalence of DM was 31%. The prevalence of DM was highest in patients with nonalcoholic fatty liver disease (56%), cryptogenic (51%), hepatitis C (32%), or alcoholic (27%) cirrhosis. For assessing prevalence of DM as a function of severity of liver disease, evaluable data were available only for hepatitis C and hepatitis B cirrhosis. DM may be more prevalent in cirrhosis than previously thought. This has implications for prognosis and treatment in these patients.
A pilot wastewater‐based epidemiology assessment of anabolic steroid use in Queensland, Australia
Authors: Shimko Katja M. , O'Brien Jake W. , Barron Leon , Kayalar Hasan , Mueller Jochen F. , Tscharke Ben J. , Choi Phil M. , Jiang Hui , Eaglesham Geoff , Thomas Kevin V.
Published: March 2019

Anabolic‐androgenic steroids are synthetic compounds prohibited due to their performance‐enhancing characteristics. The use of these substances is known to cause health‐related issues, which highlights the importance of being able to evaluate the scale of consumption by the general population. However, most available research on the analysis of anabolic steroids is focused on animals and athletes in connection with doping. The potential of wastewater‐based epidemiology as an intelligence tool for the assessment of community level use of anabolic steroids is presented herein. A liquid chromatography tandem mass spectrometry method was developed for the analysis of 10 anabolic‐androgenic steroids and 14 endogenous hormones in influent wastewater. The validated method was applied to sixteen 24‐hour composite wastewater influent samples that were collected over a period of five years from two wastewater treatment plants in Queensland, Australia. Nine investigated compounds were found to be present at concentrations between 14 and 611 ng L−1 which translated into 3–104 mg excreted per 1000 individuals per day. It was concluded that the developed analytical method is suitable for the analysis of AAS in wastewater matrix. Additionally, both the inclusion of metabolites and further investigation into deconjugation by enzymatic hydrolysis would aid in understanding and evaluating community anabolic steroid use. For the first time, this study presents the application of wastewater‐based epidemiology on anabolic‐androgenic steroids in Australia.
Does body size predict the buzz‐pollination frequencies used by bees?
Authors: De Luca Paul A. , Buchmann Stephen , Galen Candace , Mason Andrew C. , Vallejo‐Marín Mario
Published: March 2019

Body size is an important trait linking pollinators and plants. Morphological matching between pollinators and plants is thought to reinforce pollinator fidelity, as the correct fit ensures that both parties benefit from the interaction. We investigated the influence of body size in a specialized pollination system (buzz‐pollination) where bees vibrate flowers to release pollen concealed within poricidal stamens. Specifically, we explored how body size influences the frequency of buzz‐pollination vibrations. Body size is expected to affect frequency as a result of the physical constraints it places on the indirect flight muscles that control the production of floral vibrations. Larger insects beat their wings less rapidly than smaller‐bodied insects when flying, but whether similar scaling relationships exist with floral vibrations has not been widely explored. This is important because the amount of pollen ejected is determined by the frequency of the vibration and the displacement of a bee's thorax. We conducted a field study in three ecogeographic regions (alpine, desert, grassland) and recorded flight and floral vibrations from freely foraging bees from 27 species across four families. We found that floral vibration frequencies were significantly higher than flight frequencies, but never exceeded 400 Hz. Also, only flight frequencies were negatively correlated with body size. As a bee's size increased, its buzz ratio (floral frequency/flight frequency) increased such that only the largest bees were capable of generating floral vibration frequencies that exceeded double that of their flight vibrations. These results indicate size affects the capacity of bees to raise floral vibration frequencies substantially above flight frequencies. This may put smaller bees at a competitive disadvantage because even at the maximum floral vibration frequency of 400 Hz, their inability to achieve comparable thoracic displacements as larger bees would result in generating vibrations with lower amplitudes, and thus less total pollen ejected for the same foraging effort.
Zinc Complexes with Tridentate Pyridyl‐Pyrrole Ligands and their Use as Catalysts in CO2 Fixation into Cyclic Carbonates
Authors: Chen Jing‐Jing , Xu Yao‐Chun , Gan Zhi‐Liang , Peng Xiao , Yi Xiao‐Yi
Published: March 2019

Pyridyl‐pyrrole ligands usually mimic the polypyridine ligand, and their metal complexes are interesting due to their rich coordination chemistry and their use in molecular devices, biological therapeutics, and catalytic transformations. Cs‐symmetric HL3 ligand Br‐substituted on one of the pyridyl rings was designed and synthesized by Paal–Knorr pyrrole condensation. Ligand HL4 was synthesized by Suzuki‐coupling reaction between HL3 and 2‐thiopheneboronic acid in the presence of K2CO3 and Pd(PPh3)4 in degassed THF/H2O solution. Zinc complexes 1–5 with HL1 to HL5 were prepared by treatment of the corresponding pyridyl‐pyrrole ligands with diethylzinc in toluene at 0 °C in high yield. Ligand HL3 and all zinc complexes are characterized by X‐ray diffraction analysis. The structure of free HL3 is planar. The geometries at Zn in 1, 2, and 5 are compressed octahedra, while in 3 and 4 they are perhaps best described as being between cis‐divacant octahedral and distorted tetrahedral. In these zinc complexes, shorter Zn–Npyrrole [1.878(5)‐1.950(4) Å] and longer Zn–Npyridine [2.108(5)‐2.509(3) Å], Zn‐Npendant pyridine [2.802(2)‐3.039(3) Å] bond lengths are observed. Complexes 2 and 3 were used as catalysts to promote the coupling reaction of CO2 and various epoxides under solvent‐free conditions, and the catalytic mechanism was investigated by 1H NMR spectroscopy.
Bioaccumulation of Selected Halogenated Organic Flame Retardants in Lake Ontario
Authors: Kurt-Karakus Perihan B. , Muir Derek C.G. , de Jourdan Benjamin , Teixeira Camilla , Epp Martindale Jessica , Embers Heather , Wang Xiaowa , Keir Mike , Backus Sean
Published: March 2019

The trophic magnification of polybrominated diphenyl ethers (PBDEs) and selected nonlegacy halogenated organic compounds (HOCs) was determined in the food web of Lake Ontario (ON, Canada). In all, 28 Br3-Br8-PBDEs and 24 HOCs (10 of which had not been targeted previously) were analyzed. Average concentrations of Σ28PBDEs in fish ranged between 79.7 ± 54.2 ng/g lipid weight in alewife (Alosa pseudoharengus) and 815 ± 695 ng/g lipid weight in lake trout (Salvelinus namaycush). For invertebrates, concentrations were between 13.4 ng/g lipid weight (net plankton; >110 μm) and 41.9 ng/g lipid weight in Diaporeia (Diaporeia hoyi). Detection frequency (DF) for HOCs was highest for anti-Dechlorane Plus (anti-DDC-CO), 1,3-diiodobenzene (1,3-DiiB), tribromo-methoxy-methylbenzene (ME-TBP), allyl 2,4,6-tribromophenyl ether (TBP-AE), pentabromocyclododecene (PBCYD), α+β-tetrabromocylcooctane (TBCO), 2-bromoallyl 2,4,6-tribromophenyl ether (BATE), and pentabromotoluene (PBT; DF for all = 100% in lake trout). Tetrabromoxylene (TBX), dibromopropyl 2,4,6-tribromophenyl ether (TBP-DBPE), and syn-DDC-CO were also frequently detected in trout (DF = 70–78%), whereas 2,3,4,5,6-pentabromoethyl benzene (PBEB) was detected only in plankton. Several HOCs were reported in aquatic biota in the Great Lakes (USA/Canada) for the first time in the present study, including PBCYD, 1,3DiiB, BATE, TBP-DBPE, PBT, α + β-TBCO, and ME-TBP. The Br4-6-BDEs (−47, −85, −99, −100, −153, and −154) all had prey-weighted biomagnification factors (BMFPW) values >6, whereas BMFPW values for Br7-8-BDEs were <1. The highest BMFPW values of non-PBDEs were for TBP-DBPE (10.6 ± 1.34) and ME-TBP (4.88 ± 0.60), whereas TBP-AE had a BMFPW value of <1. Significant (p≤ 0.05) trophic magnification factors (TMFs), both positive and negative, were found for Br4-8-BDEs (BDE 196 = 0.4; BDE 154 = 9.5) and for bis(2,4,6-tribromophenoxy)ethane (BTBPE; 0.53), PBCYD (1.8), 1,3-DiiB (0.33), and pentabromobenzene (PBB; 0.25). Food chain length was found to have a significant influence on the TMF values. Environ Toxicol Chem 2019;38:1198–1210. © 2019 SETAC

Abstract
Effects of Sublethal Chlorpyrifos Exposure on Postlarval American Lobster (Homarus americanus)
Authors: Taylor Laura J. , Mann Nicole S. , Daoud Dounia , Clark K. Fraser , van den Heuvel Michael R. , Greenwood Spencer J.
Published: March 2019

The organophosphate pesticide chlorpyrifos has been introduced to the marine environment via adsorption to agricultural soil runoff or as spray drift. Chlorpyrifos affects the survival of some larval decapod crustaceans, but no data exist on the impacts to the American lobster, Homarus americanus. The purpose of the present study was to assess the levels at which chlorpyrifos affects the survival of postlarval H. americanus. Using acute saltwater exposures, the 24- and 48-h median lethal concentrations were established for stage IV H. americanus (1.56 and 1.33 µg/L, respectively). Movement, acetylcholinesterase activity, intermoult period, specific growth rate, and moult increment were measured during exposure to sublethal concentrations. Movement patterns were assessed to establish a 48-h median inhibition concentration for cessation of normal movement (0.66 µg/L). Acetylcholinesterase activity was found to be inhibited immediately post-exposure to 0.50, 0.57, and 0.82 µg/L chlorpyrifos but could be recovered within a period (9–15 d) in clean seawater. Sublethal growth effects of increased intermoult period, decreased specific growth rate, and decreased moult increment were observed during exposure to an environmentally relevant concentration (0.82 µg/L). The present study suggests that H. americanus stage IV larvae were marginally less sensitive to chlorpyrifos compared with other decapods and that acute lethality of H. americanus postlarvae is not likely to occur with chlorpyrifos concentrations previously reported from aquatic environments. Environ Toxicol Chem 2019;38:1294–1301. © 2019 SETAC
Local experts finding using user comments in location‐based social networks
Authors: Cao Jiuxin , Yang Yuntao , Cao Biwei , Xue Lingyun , Li Shancang , Iqbal Muddesar , Mumtaz Shahid
Published: March 2019

The opinions of local experts in the location‐based social network are of great significance to the collection and dissemination of local information. In this paper, we investigated in‐depth how the user comments can be used to identify the local expert over social networks. We first illustrate the existences of potential local experts in a social network using a scored model by considering the personal profiles, comments, friend relationship, and location preferences. Then, a multidimensional model is proposed to evaluate the local expert candidates and a local expert discovery algorithm is proposed to identify local experts. Meanwhile, a scoring algorithm is proposed to train the weights in the model. Finally, an expert recommendation list can be given based on the score ranks of the candidates. Experimental results demonstrate the effectiveness of proposed model and algorithms.
Performance of maximum ratio combining of fluctuating two‐ray (FTR) mmWave channels for 5G and beyond communications
Authors: Olyaee Maryam , Eslami Mohsen , Haghighat Javad
Published: March 2019

Recently, a millimeter‐wave band channel model for fifth generation and beyond communications, called fluctuating two‐ray (FTR) model, has been introduced, which accurately tracks the behavior of wireless communication links in that band. In this paper, the performance of maximum ratio combining (MRC) of signals received through independent FTR channels is evaluated. Closed‐form expressions for the probability distribution of the signal‐to‐noise ratio at the output of the MRC combiner, outage probability of the system, and a tight upper bound for average bit error probability are derived. From the results obtained, it is shown that MRC for FTR channels achieves the same diversity order as MRC for Rayleigh fading, and equal to the number of diversity branches. Additionally, the effects of the FTR fading model parameters on the system performance have been investigated via numerical results obtained from analytical derivations. Comparison between analytical and simulation results show that they are in excellent agreement. To the best of our knowledge, this is the first work to analyze the performance of MRC for FTR channels.
Retracted: Design and implementation of music teaching assistant platform based on Internet of Things
Authors: Li Wajia
Published: March 2019

With the development of society, Internet of Things (IoT) technology has attracted more and more attention. This paper uses IoT technology to enhance the music teaching assistant platform. Firstly, through analyzing users' requirements for music teaching assistant platform, based on IoT technology, the assistant platform is analyzed, and the wireless information transmission system is established. Secondly, aiming at the consumption of router nodes, the consumption model of nodes is established. By analyzing the energy consumption and service life of router nodes, it is concluded that traditional IoT has great disadvantages. Then, an improved repair strategy of IoT is proposed according to immune algorithm. By comparing three kinds of wireless sensor networks, the improved repair strategy of IoT is better when the number of router nodes is more than 400. When it comes to saving energy, there are great advantages in quantity consumption. Finally, by simulating and analyzing the fault repair of router nodes, it is concluded that the number of effective router nodes in traditional IoT decreases the fastest with the number of simulated runs, followed by energy‐gathering IoT, and the lifetime of effective router nodes in IoT is the longest with the energy‐gathering improved by immune algorithm. This research mainly focuses on the energy consumption of router nodes in the perception layer of IoT, as well as the network immunity and repair mechanism of the system. It improves and designs the traditional music teaching assistant platform, which has certain practical significance.
Genesis of the Huangshaping W–Mo–Cu–Pb–Zn deposit, South China: Role of magmatic water, metasomatized fluids, and basinal brines during intra‐continental extension
Authors: Li Huan , Palinkaš Ladislav A. , Evans Noreen J. , Watanabe Koichiro
Published: March 2019

The Huangshaping world‐class W–Mo–Cu–Pb–Zn deposit formed during Jurassic intra‐continental extension in the central Nanling region (South Hunan), South China. In order to assess the role of fluids in ore genesis and the origin of polymetallic mineralization, three types of mineralized porphyries (quartz porphyry, granophyre, and granite porphyry) were studied. The multi‐method approach included whole‐rock Sr–Nd isotopic geochemistry and determination of the trace element content and gaseous and aqueous composition of ore minerals from the three stages of intrusion and ore emplacement. Geochemical results show that the Sr–Nd isotopes in these altered porphyries were strongly affected by fluid metasomatism. The 87Sr/86Sr and 147Sm/144Nd ratios for the quartz porphyry and granophyre range from 0.72894 to 0.83093 and 0.1524 to 0.2080, respectively, whereas higher and considerably more variable ratios were determined for the granite porphyry (0.90396 to 1.51943 and 0.2391 to 0.2914). These observations imply that granite porphyry‐associated W–Mo mineralization underwent more intensive fluid–rock interaction. The relatively low REE concentrations and high abundances of CH4 and H2 in the Cu ores associated with the quartz porphyry unambiguously suggest a deep‐sourced magmatic fluid for the Cu mineralization. The high REE concentrations, pronounced negative Eu anomalies, M‐type tetrad effects, and high CO2, H2O, and Ca2+ contents of the W–Mo ores associated with the granite porphyry imply that the W–Mo polymetallic mineralization was formed in a relatively oxidizing, high‐temperature environment with strong metasomatism. In contrast, the slightly negative Eu anomalies, W‐type tetrad effects, low CH4, and high F− and Cl− concentrations of the Pb–Zn ores indicate involvement of a sediment‐derived basinal brine and reducing mineralization conditions. Collectively, a three‐stage genetic model is proposed for the Huangshaping polymetallic deposit. Corresponding to initiation, development, and cessation of Jurassic intra‐continental extension, magmatic water, metasomatized fluids, and basinal brines played key sequential roles in Cu, W–Mo, and Pb–Zn mineralization.
Stressful life events and cognitive decline: Sex differences in the Baltimore Epidemiologic Catchment Area Follow‐Up Study
Authors: Munro Cynthia A. , Wennberg Alexandra M. , Bienko Nicholas , Eaton William W. , Lyketsos Constantine G. , Spira Adam P.
Published: March 2019

Introduction

The reasons why women are at higher risk than men for developing dementia are unclear. Although studies implicate sex differences in the effect of stress on cognitive functioning, whether stressful life events are associated with subsequent cognitive decline has received scant research attention.

Methods

In Wave 3 (1993–1996) of the Baltimore Epidemiologic Catchment Area study, 337 men and 572 women (mean age = 47 years) reported recent (within the last year) and remote (from 1981 until 1 year ago) traumatic events (eg, combat) and stressful life events (eg, divorce/separation). At Waves 3 and 4 (2004–2005), they completed the Mini Mental State Examination (MMSE) and a word‐list memory test. Multivariable models were used to examine the association between traumatic and stressful life events at Wave 3 and cognitive change by Wave 4.

Results

A greater number of recent stressful life events at Wave 3, but not of more remote stressful events, was associated with greater verbal memory decline by Wave 4 in women but not in men. Stressful events were not associated with change in MMSE, and there were no associations between traumatic events occurring at any time and subsequent memory or MMSE decline in either sex.

Conclusions

Unlike men, middle‐aged women with a greater number of recent stressful life events demonstrate memory decline over a decade later. Sex differences in cognitive vulnerability to stressful life events may underlie women's increased risk of memory impairment in late life, suggesting that stress reduction interventions may help prevent cognitive decline in women.
District‐level impacts of health system decentralization in Indonesia: A systematic review
Authors: Rakmawati Trisya , Hinchcliff Reece , Pardosi Jerico Franciscus
Published: March 2019

The local‐level impacts of decentralizing national health systems are significant yet infrequently examined. This review aims to assess whether localized health services delivery in Indonesia, which commenced a health system decentralization process in 2001, achieved its objectives or could be enhanced.

A systematic review was undertaken to collate published evidence regarding this topic and synthesize key findings holistically using the six building blocks framework of the World Health Organization (WHO) to categorize health system performance. Four research databases were searched in 2016 for relevant evidence published between 2001 and 2015. The inclusion criteria were relevance to the topic of decentralization impacts at the district level, original research, and published in English. Included articles were appraised for quality using a standardized tool, with key findings synthesized using the WHO building blocks. Twenty‐nine articles met the inclusion criteria and categorized under the WHO building blocks categories.

The findings highlight problematic impacts of decentralization related to three building blocks: service delivery, health financing, and workforce. In the 15 years of post‐decentralization in Indonesia, the service delivery, health workforce, and health financing blocks should be prioritized for further research and policy evaluation to improve the overall health system performance at the district level.
Effects of olanzapine during cognitive and emotional processing in schizophrenia: A review of functional magnetic resonance imaging findings
Authors: Del Fabro Lorenzo , Delvecchio Giuseppe , D'Agostino Armando , Brambilla Paolo
Published: March 2019

Objective

Olanzapine is an atypical antipsychotic that is widely used in the treatment of schizophrenia and has shown some degree of efficacy on negative and cognitive symptoms. We aimed to review the effects of olanzapine treatment on brain regions that are directly involved in cognitive and emotional processing.

Methods

We used the PubMed database to perform a bibliographic search on functional magnetic resonance imaging studies that investigated the effects of olanzapine treatment on neural activity in patients with schizophrenia during cognitive and emotional tasks.

Results

Despite the high variability of tasks and analysis methods employed, the weight of the evidence was consistent with the hypothesis that olanzapine treatment is associated with a normalization of brain activity in schizophrenia. Distinctive functional changes were found in frontal cortex and cingulate cortex activity during both cognitive and emotional tasks. During emotional processing, olanzapine treatment seems to specifically regulate the activity of the striatum and limbic system.

Conclusions

The results of the reviewed studies suggest that in patients with schizophrenia, olanzapine treatment might lead to a more physiological brain activity coupled with regulation of dopamine release. Future studies should further corroborate these hypotheses using larger samples and homogeneous experimental tasks.
Remote-sensing Based Assessment of Long-term Riparian Vegetation Health in Proximity to Agricultural Lands with Herbicide Use History
Authors: Yousef Foad , Gebremichael Mekonnen , Ghebremichael Lula , Perine Jeffrey
Published: March 2019

Riparian ecosystems provide various ecosystem services including habitat for a variety of plant and animal communities, biofiltering, and stabilizing stream and river systems. Due to their location, riparian zones often share long borders with agricultural fields where herbicides are commonly applied to eliminate unwanted plants. There is a general concern that exposure of riparian vegetation to off-target drifted herbicides may adversely impact their health and diversity. We utilized the Normalized Difference Vegetation Index (NDVI) to investigate the long-term (between 1992 and 2011) trend of riparian vegetation health at 17 locations in the Midwest and Great Plains areas of the United States, where herbicide usage was likely most intense. Assessment of NDVI data demonstrated that long-term vegetation health did not decline for the studied riparian zones located in proximity to croplands during spring months (April and May). During summer (June and July), while the long-term vegetation health did not decline for the majority of the sites, there were a few cases in Kansas and Nebraska with a decline in vegetation health (negative-trending NDVI). Cluster analysis of the negative-trending NDVI pixels showed that the majority of these pixels were randomly distributed throughout these riparian sites, indicating a lack of shared common causing factors. Similarly, proximity analysis suggested that distance from croplands was not associated with the decline of vegetation health found in these sites, suggesting that exposure to herbicide drift may not be a plausible factor because this would have shown higher impact on pixels closer to the cropland. Changes in canopy coverage and vegetation diversity also did not show any dependence on distance from croplands. Finally, the remote-sensing–based NDVI data sets used provide only an indirect way of assessing the impact of herbicide drift, and therefore, further work based on field survey data is recommended to completely isolate the impacts of herbicides. Integr Environ Assess Manag 2019;15:528–543. © 2019 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC)
Discrepancies between clinical staging and surgicopathologic findings in early‐stage cervical cancer and prognostic significance
Authors: Chen Chunlin , Zhang Weifeng , Liu Ping , Su Guidong , Gong Shipeng , Li Weili
Published: March 2019

Objective

To investigate discrepancies between clinical staging and surgicopathologic findings in early‐stage cervical cancer and explore the prognostic significance of these discrepancies.

Methods

A retrospective review of the clinical records of individuals with early‐stage cervical cancer who underwent primary radical surgery in Nanfang Hospital of Southern Medical University, Guangzhou, China, between 2007 and 2013. Discrepancies in clinical staging were investigated by using surgicopathologic findings as the reference. Individuals were classified according to the type of discrepancy. Kaplan‐Meier plots were generated to explore the prognostic significance of stage discrepancies.

Results

Among 266 individuals included in the study, 182 (68.4%) were accurately staged, 58 (21.8%) were clinically over‐staged, and 26 (9.8%) were clinically under‐staged. More relapses (19.2% vs 4.9% vs 6.8%, P=0.027) and deaths (11.5% vs 2.2% vs 3.4%, P=0.048) were observed among those who were clinically under‐staged than among those who were accurately or clinically over‐staged. Clinical under‐staging was associated with poorer disease‐free survival (P=0.003) and poorer overall survival (P=0.020) over a median follow‐up of 43.9 months.

Conclusion

Significant discrepancies were found between clinical staging and surgicopathologic findings in early‐stage cervical cancer. Stage discrepancies were found to have prognostic significance, with clinical under‐staging identified as a potential adverse prognostic factor.