bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced enantioselectivity of native α‐cyclodextrins by the synergy of chiral ionic liquids in capillary electrophoresis
Authors: Zhang Qi , Zhang Jian , Xue Song , Rui Mengjie , Gao Bin , Li Ang , Bai Jiashuai , yin Zhichao , Anochie Ebubedike Mitchelle
Published: October 2018

In the cyclodextrins family, the native α‐cyclodextrin has almost been abandoned in capillary electrophoresis chiral separation due to its much weaker enantioselectivity compared with β‐cyclodextrin and their derivatives. In this work, several amino acid chiral ionic liquids were selected to establish synergistic enantioseparation systems with native α‐cyclodextrin. Enhanced enantioselectivities were observed in the chiral ionic liquids/α‐cyclodextrin synergistic systems compared with single α‐cyclodextrin system. A series of comparison experiments were performed to demonstrate the superiority of the synergistic systems. Primary parameters affecting the enantioseparation were systematically optimized, including the type and concentration of chiral ionic liquids, α‐cyclodextrin concentration, buffer pH, and applied voltage. Best separations of the model enantiomers were obtained in a 20 mM Tris/H3PO4 buffer at pH 2.5 containing 3% (m/v) α‐cyclodextrin and 30 mM tetramethylammonium‐l‐arginine. The results show that the α‐cyclodextrin is also worth our attention when selecting chiral selectors for capillary electrophoresis enantioseparation of specific racemic compound.
Ratiometric fluorescence nanosensors based on core‐shell structured carbon/CdTe quantum dots and surface molecularly imprinted polymers for the detection of sulfadiazine
Authors: Chen Xiaoqiang , Luan Yu , Wang Ningwei , Zhou Zhiping , Ni Xiaoni , Cao Yunfei , Zhang GuangShe , Lai Yufeng , Yang Wenming
Published: October 2018

Sulfadiazine is an environmental pollutant derived from abuse of antibiotics. Its content in environmental water is closely related to human health. Thus, a novel dual‐emission surface molecularly imprinted nanosensor is designed for the specific adsorption and detection of sulfadiazine. In the system, blue emissive carbon quantum dots wrapped with silica served as the internal reference signal for eliminating background interference, while red emissive thioglycolic acid modified CdTe quantum dots (CdTe QDs), which are low dimensional semiconductor materials by the combination of cadmium and tellurium with excellent optical properties, were encapsulated in the imprinted layer to offer recognition signal. The fluorescence of CdTe quantum dots was quenched and the fluorescence quenching degree of carbon quantum dots was inconspicuous with the increase of concentration of sulfadiazine, thereby reflecting the color change. The detection of sulfadiazine was successfully achieved in a concentration range of 0.25–20 μmol/L with detection limit of 0.042 μmol/L and nanosensors had specific recognition for sulfadiazine over its analogues. Compared to single‐emission fluorescence sensors, ratiometric fluorescence nanosensors had wider linear range and higher detection accuracy. Furthermore, the nanosensors were also successfully applied for the determination of sulfadiazine in real water and milk samples with acceptable recoveries. The study provides a feasible method for the detection of sulfadiazine and a reference for the detection of sulfonamides.
High‐speed rail and tourism in China: An urban agglomeration perspective
Authors: Li Leona S.Z. , Yang Fiona X. , Cui Chuantao
Published: October 2018

This work aims to provide a comprehensive analysis of the association between high‐speed rail (HSR) operation and tourist arrivals in China. A panel data of 238 prefecture‐level cities from 2003 to 2013 is analyzed, using both system generalized method of moments estimation and synthetic control methods. Nationwide, HSR implementation generates sizable tourist inflows, with stronger effect for international arrivals than for domestic ones. Furthermore, heterogeneous HSR impacts are identified through the lens of urban agglomeration: (a) Connection with core cities is quintessential in channeling international customers to the hinterlands, and (b) national cores and hinterlands benefit prominently whereas regional cores lose from HSR accessibility.
The moderating role of nationality in residents' perceptions of the impacts of tourism development in the United Arab Emirates
Authors: Hammad Nada Malalla , Ahmad Syed Zamberi , Papastathopoulos Avraam
Published: October 2018

The purpose of this paper is to investigate residents' perceptions of tourism impacts and whether nationality moderates the relationship between these perceptions and support for tourism development in the UAE. Using data collected from 979 respondents from the UAE, a questionnaire assessed the moderating effect of nationality on residents' perceptions of the social, cultural, environmental, and economic impacts of tourism. Social exchange theory is used as a theoretical framework for this study because it considers the heterogeneity of a community and explains the different perceptions held within it. The findings of this study show that nationality moderates the relationship between residents' perceptions of the impacts of tourism and their support for tourism development in the UAE. Specifically, nationality moderates the relationship between residents' perceptions of negative social impacts, positive cultural impacts, and negative and positive economic impacts and their support for tourism development. This study can assist tourism officials in the UAE in developing strategies that consider the diversity of a community with respect to the nationality of its residents.
Blow‐up of solution of wave equation with internal and boundary source term and non‐porous viscoelastic acoustic boundary conditions
Authors: Vicente André
Published: October 2018

In this paper we study the blow‐up of solution of a mixed problem associated to a nonlinear wave equation with dissipative and source term in a bounded domain of . On a boundary portion of the domain we consider a non‐porous viscoelastic acoustic boundary conditions to a non‐locally reacting boundary.
Mediterranean diet adherence is related to reduced probability of prodromal Parkinson's disease
Authors: Maraki Maria I. , Yannakoulia Mary , Stamelou Maria , Stefanis Leonidas , Xiromerisiou Georgia , Kosmidis Mary H. , Dardiotis Efthimios , Hadjigeorgiou Georgios M. , Sakka Paraskevi , Anastasiou Costas A. , Simopoulou Eleni , Scarmeas Nikolaos
Published: October 2018

Background

The International Parkinson and Movement Disorder Society recently introduced a methodology for probability score calculation for prodromal PD.

Objectives

To assess the probability of prodromal PD in an older population and investigate its possible association with Mediterranean diet adherence.

Methods

Data from a population‐based cohort study of older adults (HEllenic Longitudinal Investigation of Aging and Diet) in Greece were used. Probability of prodromal PD was calculated according to International Parkinson and Movement Disorder Society research criteria. A detailed food frequency questionnaire was used to evaluate dietary intake and calculate Mediterranean diet adherence score, ranging from 0 to 55, with higher scores indicating higher adherence.

Results

Median probability of prodromal PD was 1.9%, ranging from 0.2 to 96.7% in 1,731 PD‐free individuals aged ≥ 65 (41% male). Lower probability for prodromal PD (P < 0.001) in the higher Mediterranean diet adherence groups was noted, driven mostly by nonmotor markers of prodromal PD, depression, constipation, urinary dysfunction, and daytime somnolence. Each unit increase in Mediterranean diet score was associated with a 2% decreased probability for prodromal PD (P < 0.001). Compared to participants in the lowest quartile of Mediterranean diet adherence, those in the highest quartile were associated with a ∼21% lower probability for prodromal PD.

Conclusions

Adherence to the Mediterranean diet is associated with lower probability of prodromal PD in older people. Further studies are needed to elucidate the potential causality of this association, potential relation of the Mediterranean diet to delayed onset or lower incidence of PD, as well as the underlying neurobiological mechanisms. © 2018 International Parkinson and Movement Disorder Society
Structure‐based Discovery of Novel CK2α‐Binding Cyclic Peptides with Anti‐cancer Activity
Authors: Tang Shan , Zhang Na , Zhou Yue , Cortopassi Wilian A. , Jacobson Matthew P. , Zhao Li‐jiao , Zhong Ru‐gang
Published: October 2018

Protein kinase CK2 is considered as an emerging target in cancer therapy, and recent efforts have been made to develop its ATP‐competitive inhibitors, but achieving selectivity with respect to related kinases remains challenging because of the highly conserved ATP‐binding pocket of kinases. Non‐ATP competitive inhibitors might solve this challenge; one such strategy is to identify compounds that target the CK2α/CK2β interface as CK2 holoenzyme antagonists. Here we improved the binding affinity to CK2α and cell‐based anti‐cancer activity of a CK2β‐derived cyclic peptide (Pc) by combining structure‐based computational design with experimental evaluation. By analyzing molecular dynamics simulations of Pc bound to CK2α, a series of Pc‐derived peptides was rationally designed and synthesized to evaluate their binding affinity to CK2α, as well as anti‐proliferative and pro‐apoptotic effects against HepG2 cancer cell line. One amino acid substitutions on Pc, I192F, exhibited over 10‐fold improvement in the predicted binding affinity to CK2α when compared to Pc, and a cell‐permeable version, I192F‐Tat, also demonstrated more potent anti‐proliferative and pro‐apoptotic effects against HepG2 compared to Pc. A second modification of Pc, H193W, also led to more potent cell‐based activity, despite having weaker binding affinity (∼5×) to CK2α. The discovery of the I192F and H193W peptides provides new insights for further optimization of CK2 antagonist candidates as anti‐cancer leads.
An 8 GS/s 20 GHz bandwidth master‐slave track‐and‐hold amplifier in 65 nm CMOS
Authors: Na Yunsik , Mehmood Zubair , Kang Sungbin , Jung Heechang , Seo Munkyo
Published: October 2018

A 65 nm CMOS fully‐differential track‐and‐hold amplifier (THA) in master‐slave configuration is presented. For high‐speed operation, Cherry‐Hooper amplifier with input inductive‐peaking and switched‐source follower (SSF) circuit are used for the front‐end preamplifier and master/slave track‐and‐hold circuits, respectively. On‐wafer testing in single‐ended input/output configuration shows that the fabricated THA exhibits 20 GHz switched‐mode bandwidth and 11.9 dB conversion gain at 8 GS/s clock, with THD < −36 dB and SFDR >36 dB within the 3‐dB bandwidth, while consuming 361 mW of dc power at 2.6 V supply. This work represents the highest input bandwidth for master‐slave THA in CMOS, to the best of authors' knowledge. The chip area is 0.681 mm2 including pads (active chip area: 0.2 mm2).
Multiband microstrip MIMO antenna with CSRR loaded for GSM and LTE applications
Authors: Asadpor Loghman , Rezvani Mirhamed
Published: October 2018

A multiband multiple‐input multiple‐output (MIMO) microstrip patch antenna using complementary split‐ring resonator (CSRR) structure is proposed for Global System for Mobile (GSM) and Long‐Term Evolution (LTE) applications. The proposed antenna consists of two radiating patches with folded microstrip lines and symmetric L‐shaped slots, which are connected together with an isolation line for reducing the coupling effect between ports. CSSRs are used to enhance the isolation and to control resonant frequencies. Radiation elements of the antenna are designed for various applications such as GSM (900 MHz) and LTE (1900/2300/2600 MHz). The proposed antenna is fed by 50 Ω CPW lines. Various parameters calculated in this antenna show a return loss and an isolation of less than −10 dB and −15 dB respectively. Moreover, the gain of 2.8dBi and the radiation efficiency of 72% have been obtained for proposed antenna. The presented antenna occupying 60 × 70 × 0.8 mm3 is implemented on an FR4 substrate.
A Novel Laser ranging method based on adaptive Kalman filter technology
Authors: Xu Xiaobin , Luo Minzhou , Pei Ronghao , Tan Zhiying
Published: October 2018

Aiming at the problem of ranging accuracy of laser radar, a laser ranging method based on adaptive Kalman filter is proposed. According to the pulsed laser ranging method and acceleration model based on Wiener process, the standard Kalman filter algorithm is established. In order to solve the problem that the statistical characteristics of laser ranging noise are inconsistent with the actual noise, the autocovariance least squares method is used to estimate the noise parameters. The Monte Carlo method is used to simulate ranging results of laser radar and evaluate the performance of different methods. The adaptive Kalman filtering algorithm using autocovariance least squares method can better adjust the noise parameters and improve the distance measurement accuracy than the traditional Kalman filter algorithm. The experiment of the actual static ranging is carried out. The experiment results show that the SD of laser ranging is reduced from 10.9 to 4.8 mm by using proposed method.
X‐band 12 W power amplifier MMIC designed with second harmonic suppression
Authors: Tao Hong‐Qi , Hong Wei , Zhang Bin
Published: October 2018

Two X‐band (8‐12GHz) GaAs high‐power amplifier MMICs with and without compact second harmonic suppression cells are presented in this letter. The compact second harmonic suppression cell consists of an inductor and a capacitor in series, which is equivalent to a capacitance in the fundamental frequency range while resonates at the second harmonic frequency. The power amplifier MMIC with compact second harmonic suppression cells delivers more than 12 W output power with over 33% power added efficiency and with more than 52dBc second harmonic suppression over the band of 8‐12GHz. The two chips have the same size as 3.2 × 4 mm.2
Design of high‐power W‐band push‐push oscillators using load‐pull technique
Authors: Choe Wonseok , Jeong Jinho
Published: October 2018

New design method of push‐push oscillators is proposed using harmonic load‐pull simulation to determine optimum load impedances at both fundamental (f0) and second harmonic frequencies (2f0). It allows high output power at 2f0 while meeting oscillation condition at f0. In addition, the compact self‐biasing source feedback is proposed using coupled line for negative resistance generation. The proposed method is applied to the design of W‐band high power push‐push oscillator using 0.15 μm GaAs pseudo‐morphic high electron mobility transistors (pHEMTs) with typical maximum oscillation frequency (fmax) of 180 GHz. The measurement shows an output power of 2.2 dBm at 92.3 GHz with a phase noise performance of −84 dBc/Hz at 1 MHz offset frequency. This result corresponds to relatively high output power at this frequency compared with reported oscillators using GaAs HEMTs with higher fmax's.
Global method for stability analysis of anchored slopes
Authors: Zhang Tan , Zheng Hong , Sun Cong
Published: October 2018

Based on the global method, an approach is proposed to consider the effect of anchor reinforcement on slope stability, where equilibrium conditions are formulated in terms of the whole slip body. Anchor pre‐tension is assumed to be undertaken by the whole slip body instead of individual slices, causing internal force within slope more realistic. Meanwhile, the optimization model for locating the critical slip surface is of weak nonlinearity and easy to solve using the conventional optimization procedures. The effects of anchoring orientation and position are thoroughly investigated, and interesting results are obtained.
Contribution of psychiatric diagnoses to extent of opioid prescription in the first year post‐head and neck cancer diagnosis: A longitudinal study
Authors: Henry Melissa , Alias Ali , Frenkiel Saul , Richardson Keith , Hier Michael , Zeitouni Anthony , Kost Karen , Mlynarek Alex , Black Martin , MacDonald Christina , Chartier Gabrielle , Rosberger Zeev
Published: October 2018

Purpose

The purpose of this study was to determine, within the first‐year post–head and neck cancer (HNC) diagnosis, the contribution of past and upon HNC psychiatric diagnoses (ie, substance use disorder, major depressive disorder, and anxiety disorder) to the extent (ie, cumulated dose) of opioid prescription.

Methods

Prospective longitudinal study of 223 consecutive adults (on 313 approached; 72% participation) newly diagnosed (<2 weeks) with a first occurrence of primary HNC, including Structured Clinical Interviews for DSM‐IV disorders, validated psychometric measures, and medical chart reviews. Opioid doses were translated into standardized morphine milligram equivalents (MME) using CDC guidelines. A model of variables was tested using multiple linear regression.

Results

Fifty‐five percent (123/223) of patients received opioids at some point during the first 12 months post–HNC diagnosis, 37.7% (84/223) upon HNC diagnosis (pre‐treatment), 40.8% (91/223) during treatments, and 31.4% (70/223) post‐treatment. The multiple linear regression indicated that an AD (P = 0.04) upon HNC diagnosis in early stage contributes to cumulated MME dose in the first year post–HNC diagnosis.

Conclusion

This study underlines how anxiety has important repercussions on the management of pain and illustrates the importance of screening for AD upon HNC diagnosis to allow for early prophylactic treatment and support.
Front Cover: Cover Image, Volume 74, Issue 11
Authors: Lüthi Christoph , Álvarez‐Alfageme Fernando , Romeis Jörg
Published: October 2018

The front cover image is based on the Research Article The bean α‐amylase inhibitor αAI‐1 in genetically modified chickpea seeds does not harm parasitoid wasps by Christoph Lüthi et al., DOI: 10.1002/ps.4919. Source Image: © Dr. Christopher B. Jackson, IKELOS.

image
Insect midgut structures and molecules as targets of plant‐derived protease inhibitors and lectins
Authors: Napoleão Thiago H , Albuquerque Lidiane P , Santos Nataly DL , Nova Isabella CV , Lima Thâmarah A , Paiva Patrícia MG , Pontual Emmanuel V
Published: October 2018

The midgut of insects is involved in digestion, osmoregulation and immunity. Although several defensive strategies are present in this organ, its organization and function may be disturbed by some insecticidal agents, including bioactive proteins like lectins and protease inhibitors (PIs) from plants. PIs interfere with digestion, leading to poor nutrient absorption and decreasing amino acid bioavailability. Intake of PIs can delay development, cause deformities and reduce fertility. Ingestion of PIs may lead to changes in the set of proteases secreted in the insect gut, but this response is often insufficient and results in aggravation of the malnutrition status. Lectins are proteins that are able to interact with glycoconjugates, including those linked to cell surfaces. Their effects on the midgut include disruption of the peritrophic matrix, brush border and secretory cell layer; induction of apoptosis and oxidative stress; interference with nutrient absorption and transport proteins; and damaging effects on symbionts. In addition, lectins can cross the intestinal barrier and reach the hemolymph. The establishment of resistant insect populations due to selective pressure resulting from massive use of a bioactive protein is an actual possibility, but this can be minimized by the multiple mode‐of‐action of these proteins, mainly the lectins. © 2018 Society of Chemical Industry
Manipulation of Antiferromagnetic Spin Using Tunable Parasitic Magnetization in Magnetoelectric Antiferromagnet
Authors: Nozaki Tomohiro , Al‐Mahdawi Muftah , Shiokawa Yohei , Pati Satya Prakash , Ye Shujun , Kotani Yoshinori , Toyoki Kentaro , Nakamura Tetsuya , Suzuki Motohiro , Yonemura Syougo , Shibata Tatsuo , Sahashi Masashi
Published: October 2018

Antiferromagnets and ferrimagnets with a low net magnetic moment are key components for future spintronic devices because they enable high‐integration and high‐speed (on the order of THz) operations. Cr2O3 is one of the few antiferromagnets that can achieve 180° manipulation of its spin by electrical means. In this study, the authors developed a new functional material, Cr2O3, with tunable parasitic magnetization. The authors demonstrate both magnitude and direction tunability of parasitic magnetization in Cr2O3 thin films by doping. A sublattice magnetization reduction and displacement‐induced nonequivalent Cr moments by site‐selective substitution of nonmagnetic elements are inferred to be the origin of the parasitic magnetization. By utilizing the tunable parasitic magnetization, the authors demonstrate the manipulation of antiferromagnetic single domain. In addition, the authors confirm the low‐electric‐field switching ability of the antiferromagnetic spin in a doped Cr2O3/Co exchange coupling system. Such tunable parasitic magnetization enables easy manipulation and detection of antiferromagnetic spin and provides a platform for further understanding of antiferromagnets and research opportunities in innovative spintronics device applications.
Tuning the Optical Absorption Property of GeSe Thin Films by Annealing Treatment
Authors: Liu Shun‐Chang , Yang Yusi , Zhang Xing , Huang Lin‐Bo , Sun Jian‐Kun , Guan Bo , Li Xiang , Xue Ding‐Jiang , Hu Jin‐Song
Published: October 2018

As an emerging promising photovoltaic absorber material, GeSe has attracted significant interest recently due to its simple binary composition, attractive optical and electrical properties as well as earth‐abundant and low‐toxic constituents. However, no systematic study on the absorption property tuning of GeSe has been reported. Here, first it is shown that the crystallization temperature of amorphous GeSe is about 330 °C through differential thermal analysis and temperature‐dependent X‐ray diffraction. Next, GeSe films with tunable absorption property in the range of 1.79–1.14 eV are fabricated by annealing amorphous GeSe films at different temperatures. Finally, through the combined analysis of bandgaps measured by transmission spectroscopy and nanosheet thickness characterized by cross‐sectional high‐resolution transmission electron microscopy, the blue shift of bandgap with decreasing thickness of nanosheets has been attributed to the quantum confinement effect. Such continuously tunable absorption property of GeSe films makes it more useful for further optoelectronics.
Anti‐influenza activity of berberine improves prognosis by reducing viral replication in mice
Authors: Yan Yu‐Qi , Fu Ying‐Jie , Wu Sha , Qin Hong‐Qiong , Zhen Xiao , Song Bi‐Mei , Weng Yuan‐Shu , Wang Peng‐Cheng , Chen Xiao‐Yin , Jiang Zhen‐You
Published: October 2018

Berberine, a natural isoquinoline alkaloid isolated from the berberis species, has a wide array of biological properties such as anti‐inflammatory, antibacterial, antifungal, and antihelminthic effects. We evaluated the antiviral effect of berberine against influenza A/FM1/1/47 (H1N1) in vivo and in vitro. The results showed that berberine strongly suppressed viral replication in A549 cells and in mouse lungs. Meanwhile, berberine relieved pulmonary inflammation and reduced necrosis, inflammatory cell infiltration, and pulmonary edema induced by viral infection in mice when compared with vehicle‐treated mice. Berberine suppressed the viral infection‐induced up‐regulation of TLR7 signaling pathway, such as TLR7, MyD88, and NF‐κB (p65), at both the mRNA and protein levels. Furthermore, berberine significantly inhibited the viral infection‐induced increase in Th1/Th2 and Th17/Treg ratios as well as the production of inflammatory cytokines. Our data provide new insight into the potential of berberine as a therapeutic agent for viral infection via its antiviral activity.
Cytomegalovirus infection in day care centres: A systematic review and meta‐analysis of prevalence of infection in children
Authors: Zheng Qing Yu , Huynh Kim T. , van Zuylen Wendy J. , Craig Maria E. , Rawlinson William D.
Published: October 2018

Maternofetal transmission of cytomegalovirus (CMV) is the most common infectious cause of congenital malformation in developed countries. Maternal infection often results from close contact with infected children, and this may occur in day care centres (DCCs).

A systematic review of observational studies was conducted to examine the prevalence of CMV infection among children attending DCCs. Meta‐analysis using the random effect model was performed for studies including controls. Sources included PubMed, EMBASE (until August 2018), and references from identified publications. Inclusion criteria were studies reporting CMV infection prevalence among childcare children aged less than 7 years of age. Controls were children without childcare exposure. CMV infection was defined as viral excretion detected by culture, polymerase chain reaction, or CMV seropositivity.

Twenty‐eight publications including 8347 participants met the eligibility criteria. The pooled prevalence of CMV infection among children in childcare from all studies was 32% (95% CI 23‐41). Within case‐controlled studies, prevalence among children attending DCCs was 34% (95% CI 25‐44), whereas prevalence among those without childcare exposure was 22% (95% CI 15‐30). Meta‐analysis showed a significant association between DCC attendance and CMV infection (odds ratio 2.69, 95% CI 1.68‐4.30; heterogeneity χ2/df = 8; I2 = 84%,P < 0.00001).

Attendance at DCCs is significantly associated with increased risk of childhood CMV infection. Prevention strategies to reduce risk of CMV infection of pregnant women and children should involve review of DCC exposure and consideration of preventative hygiene strategies.
Sustainable development: Implications and definition for open sustainability
Authors: Ukko Juhani , Saunila Minna , Rantala Tero , Havukainen Jouni
Published: October 2018

This study deals with sustainable development from a triple bottom‐line perspective, including the economic, social, and environmental dimensions. Specifically, this study investigates whether various sustainability factors are related to small businesses' intentions to exploit open sustainability, which is described as meeting sustainability challenges through the exploitation of internal and external initiatives. Empirical data were collected from 139 companies. The results show that some factors from all three sustainability dimensions affect companies' intentions to exploit open sustainability, while company size and operations type do not influence the use of open sustainability. As an emerging concept, the definition of open sustainability is presented.
Nonlinear association structures in flexible Bayesian additive joint models
Authors: Köhler Meike , Umlauf Nikolaus , Greven Sonja
Published: October 2018

Joint models of longitudinal and survival data have become an important tool for modeling associations between longitudinal biomarkers and event processes. The association between marker and log hazard is assumed to be linear in existing shared random effects models, with this assumption usually remaining unchecked. We present an extended framework of flexible additive joint models that allows the estimation of nonlinear covariate specific associations by making use of Bayesian P‐splines. Our joint models are estimated in a Bayesian framework using structured additive predictors for all model components, allowing for great flexibility in the specification of smooth nonlinear, time‐varying, and random effects terms for longitudinal submodel, survival submodel, and their association. The ability to capture truly linear and nonlinear associations is assessed in simulations and illustrated on the widely studied biomedical data on the rare fatal liver disease primary biliary cirrhosis. All methods are implemented in the R package bamlss to facilitate the application of this flexible joint model in practice.
Optimizing and evaluating biomarker combinations as trial‐level general surrogates
Authors: Gabriel Erin E. , Sachs Michael C. , Daniels Michael J. , Halloran M. Elizabeth
Published: October 2018

We extend the method proposed in a recent work by the Authors for trial‐level general surrogate evaluation to allow combinations of biomarkers and provide a procedure for finding the “best” combination of biomarkers based on the absolute prediction error summary of surrogate quality. We use a nonparametric Bayesian model that allows us to select an optimal subset of biomarkers without having to consider a large number of explicit model specifications for that subset. This dramatically reduces the number of model comparisons needed. Given the model's flexibility, complex nonlinear relationships can be fit when enough data are available. We evaluate the operating characteristics of our proposed method in simulations designed to be similar to our motivating example. We use our method to compare and evaluate combinations of biomarkers as trial‐level general surrogates for the pentavalent rotavirus vaccine RotaTeq™ (RV5) (Merck & Co, Inc, Kenilworth, New Jersey, USA), finding that the same single biomarker identified in our previously published analysis is likely the optimal subset.
Responses to rival exit: Product variety, market expansion, and preexisting market structure
Authors: Ren Charlotte R. , Hu Ye , Cui Tony H.
Published: October 2018

Research Summary

This study investigates incumbent responses to a main rival's exit. We argue that long‐time rivals have developed an equilibrium by offering a mix of overlapping and unique products and by choosing geographic proximity to each other. A rival's exit, however, disrupts this equilibrium and motivates surviving firms to expand in both product and geographic spaces to seek a new equilibrium. Using data from all U.S. Best Buy stores before and after the exit of Circuit City, we find that Best Buy uses product variety expansion as its major response in markets where Circuit City was colocated, but it more often responds by opening new stores in non‐colocated markets. Regardless of preexisting market structures, the magnitude of product variety expansion decreases with the opening of new stores.

Managerial Summary

How do surviving firms respond to a major rival's exit? By studying Best Buy's responses to Circuit City's withdrawal, we find the survivor expands in both product space (increasing product variety) and geographic space (opening new stores), due to two motives. First, the survivor strives to fill in “holes” left in the market. Second, the survivor experiences uncertainty in the postexit world wherein its reference point is gone, threat of potential entry looms, and it lacks information about new entrants. Thus, it must deter potential entry ex ante by preempting many prime product and geographic locations. Best Buy also responds according to preexisting market structures, primarily through product variety expansion in markets wherein Circuit City was colocated and through opening new stores in non‐colocated markets.
Analyzing reviews guided by App descriptions for the software development and evolution
Authors: Liu Yuzhou , Liu Lei , Liu Huaxiao , Wang Xiaoyu
Published: October 2018

Reviews in App stores are a massive and fast‐growing data resource for developers to understand user experiences and their needs. Studies show that users often express their sentiments on App features in reviews, and this information is important for the development and evolution of Apps. To help developers gain such information efficiently, this paper proposes a method using App descriptions, another typical data in App stores, to guide the analysis of reviews. Firstly, we extract App features from descriptions, then summarize them to gain topics of App features as high‐level information; the results are formalized as a topic‐based domain model (TBDM). Secondly, we train classifiers of reviews based on the model to establish the relationships between user sentiments and App features. Finally, a quantified method is given to analyze the model based on developer preferences for recommending and summarizing reviews. To evaluate our approach, experiments were conducted using the App descriptions and reviews collected from Google Play. The results indicate that the approach can classify reviews to their related App features effectively (average F measure is 86.13%), and provides useful information for overall analyzing App features in a domain and identifying (dis)advantages of an App.
Effect of Cerium on the Behavior of Inclusions in H13 Steel
Authors: Huang Yu , Cheng Guoguang , Li Shijian , Dai Weixing
Published: October 2018

The modification mechanism of cerium (Ce) on oxides and multilayer carbontrides in H13 steel is investigated by industrial trials and thermodynamic calculations. The morphology, composition, and size of inclusions are analyzed by scanning electron microscopy and energy dispersive spectroscopy. The main inclusions in H13 steel without Ce content in the molten steel are MgAl2O4 spinel inclusions and multilayer carbonitrides. The carbonitrides have a multilayer structure in which MgAl2O4 acts as the nucleation core and the second layer is (Ti, V)(C, N). As the cerium content in molten steel increases from 0 to 0.03 wt%, the MgAl2O4 is effectively modified into cerium oxide (Ce–O) and cerium oxy‐sulfide (Ce–O–S), and the evolutionary process is as follows: MgAl2O4 → CeAlO3 → Ce–O and Ce–O–S. Likewise, the structure of multilayer carbonitrides in the H13 steel also changed. The MgAl2O4 and CeAlO3 act as heterogeneous nucleation cores of multilayer carbonitrides. However, Ce–O and Ce–O–S can effectively inhibit the heterogeneous nucleation of carbonitrides. The number density of large‐size carbontrides is remarkably reduced with increasing Ce content. A prediction model of optimum Ce content in molten steel is built, which has remarkable agreement with the experimental observations.
A simplified hybrid carrier‐based PWM technique for three‐level NPC inverters considering neutral‐point voltage balance
Authors: Chen Xi , Huang Shenghua , Li Bingzhang , Wu Fang
Published: October 2018

An in‐depth analysis and comparison between the virtual space vector pulse width modulation (VSVPWM) method and the space vector pulse width modulation (SVPWM) method is presented in this paper. Compared to SVPWM, VSVPWM can achieve the balance of the neutral‐point voltage for any load over the full range of the inverter output voltage and for all load power factors. Nevertheless, VSVPWM would cause higher dv/dt of output voltages, higher voltage total harmonic distortion, and slower voltage‐balancing dynamic. A detailed analysis on these drawbacks is given. Then, the relationship between the neutral‐point current and the factor k0, which is employed to adjust the ratio of time of application of small vectors in a pair, is studied comprehensively, and a modified zero‐sequence voltage injection method for the two‐level inverter is introduced into the small hexagons of the three‐level space vector diagram. A simplified hybrid carrier‐based pulse width modulation (PWM) method is developed. Compared to VSVPWM, the proposed PWM method is not only easy to implement voltage‐balancing control but also reduces the switching frequencies of the devices and achieves better output voltage spectra and faster voltage‐balancing dynamic. All these benefits of the proposed method are verified through experimentation. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Impact of CD39 expression on CD4+ T lymphocytes and 6q deletion on outcome of patients with chronic lymphocytic leukemia
Authors: Zaki Eman Mosaad , Zahran Asmaa Mohamed , Metwaly Alshimaa Abdelazeem , Hafez Rania , Hussein Safinaz , Mohammed Abdallah Elaiw
Published: October 2018

Objective/Background:

Chronic lymphocytic leukemia is one of the commonest leukemias affecting adults. CD39 inhibits T-cell and Natural killer (NK) cell responses by hydrolyzing adenosine triphosphate and adenosine diphosphate, suppressing the immune system. We investigated expression of CD39 on CD4+ T Lymphocytes in chronic lymphocytic leukemia (CLL) patients and its relationship with deletion 6q, its association with disease stage and survival.

Methods:

Thirty CLL patients and 20 matched controls were included in the study. Bone marrow studies with immunophenotyping, CD39, CD38, and ZAP-70, and detection of del 6q by FISH were performed.

Results:

CD39+ CD4+ T helper cells in CLL patients were significantly expressed compared with the controls (p < .001). Levels of CD39+ CD4+ T cells were significantly expressed in high risk CLL patients. Del 6q was detected in 63.3% of patients and it correlated with CD39, CD38, and ZAP-70, and advanced stage disease. There was a significant relation between response to treatment and CD39 expression and del 6q, also there was a significant difference in overall survival (OS) between patients with and without Del 6q.

Conclusion:

CD39 expression on CD4+ Tcells and del 6q act as prognostic markers in CLL. Blocking or inhibition of CD39 may be a target for new immune therapy for CLL.
Gestational folic acid supplementation does not affects the maternal behavior and the early development of rats submitted to neonatal hypoxia‐ischemia but the high supplementation impairs the dam's memory and the Na+, K+ ‐ ATPase activity in the pup's hippocampus
Authors: Deniz Bruna Ferrary , Confortim Heloísa Deola , Deckmann Iohanna , Miguel Patrícia Maidana , Bronauth Loise , de Oliveira Bruna Chaves , Vieira Milene Cardoso , dos Santos Tiago Marcon , Bertó Carolina Gessinger , Hartwig Josiane , Wyse Ângela Terezinha de Souza , Pereira Lenir Orlandi
Published: October 2018

Folic acid (FA) is a B‐complex vitamin important to the development of the fetus, being supplemented during pregnancy. Our recent findings showed that gestation supplementation (normal and excess doses) prevented the cognitive deficits and BDNF imbalance in adult rats that were submitted to neonatal hypoxia‐ischemia (HI). To better understand this protective effect, the present study aimed to evaluate whether FA supplementation could be related to (1) maternal behavior, memory and Na+, K+ ‐ ATPase activity in the hippocampus of the dams; (2) on somatic growth, early neurobehavioral development and Na+, K+ ‐ ATPase activity in the hippocampus of the offspring; and (3) the effects of this supplementation in pups submitted to neonatal HI. Pregnant Wistar rats were divided into three groups, according to the diet they received during gestation: standard diet (SD), supplemented with 2 mg/kg of FA (FA2 – normal dose) and supplemented with 20 mg/kg of FA (FA20 –excessive dose). At the 7th PND pups were submitted to the Levine‐Vannucci model of HI. During weaning the maternal behavior, the somatic growth and the neurobehavior development of pups were assessed. After weaning, the memory of the dams (by the Ox‐maze task) and the Na+, K+ ‐ ATPase activity in the hippocampus of both dams and offspring were evaluated. Considering the dams (1), both doses of FA did not alter the maternal behavior or the Na+, K+ ‐ ATPase activity in the hippocampus, but a memory deficit was observed in the high FA‐supplemented mothers. Considering the offspring (2), both FA doses did not affect the somatic growth or the neurobehavior development, but the FA20 pups had a decreased Na+, K+ ‐ ATPase activity in the hippocampus. The FA supplementation did not change the parameters evaluated in the HI rats (3) and did not prevent the decreased Na+, K+ ‐ ATPase activity in the hippocampus of the HI pups. These results indicate that normal FA supplementation dose does not influence the maternal behavior and memory and does not impact on the offspring early development in rats. Further studies are needed to confirm the effects of the high FA supplementation dose in the dams’ memory and in the Na+, K+ ‐ ATPase activity in the hippocampus of the offspring.
Risk factors of orthopedic surgical site infection in Jordan: A prospective cohort study
Authors: Najjar Yahya W. , Al-Wahsh Zeinab M. , Hamdan Mohammad , Saleh Mohammad Y.
Published: October 2018

ABSTRACT

Background:

Orthopedic surgical site infection represents a hospital acquired infection among orthopedic surgery patients, which in turn delays normal recovery process and increases hospital length of stay and health care costs. As a result, risk factors for orthopedic surgical site infection should be identified thereby allowing the application of protective interventions that may inhibit the occurrence of such infection.

Objectives:

To determine risk factors of surgical site infection in patients undergoing orthopedic surgery in Jordan.

Materials and methods:

The study employed prospective, multi-center approach to collect data about orthopedic surgery patients through assessing their health status and reviewing their medical records and monitoring for occurrence of surgical site infection within 90 days after operation.

Results:

286 patients met the eligibility criteria from 18 hospitals. Only surgical wound classification and length of postoperative stay wound were found to be significant risk factors for orthopedic surgical site infection.

Conclusion:

Surgical wound classification and length of postoperative stay were identified as risk factors for orthopedic surgical site infection. Risk factors that did not predict occurrence of orthopedic surgical site infection can be identified by other research strategies than the one used in this study, which could be conducted retrospectively or by conducting prospective studies that are both community-based and hospital-based with larger sample sizes.

Highlights:
Spectral gap property and strong ergodicity for groups of affine transformations of solenoids
Authors: BEKKA BACHIR , FRANCINI CAMILLE
Published: October 2018

Let $X$ be a solenoid, i.e. a compact, finite-dimensional, connected abelian group with normalized Haar measure $\unicode[STIX]{x1D707}$, and let $\unicode[STIX]{x1D6E4}\rightarrow \operatorname{Aff}(X)$ be an action of a countable discrete group $\unicode[STIX]{x1D6E4}$ by continuous affine transformations of $X$. We show that the probability measure preserving action $\unicode[STIX]{x1D6E4}\curvearrowright (X,\unicode[STIX]{x1D707})$ does not have the spectral gap property if and only if there exists a $p_{\text{a}}(\unicode[STIX]{x1D6E4})$-invariant proper subsolenoid $Y$ of $X$ such that the image of $\unicode[STIX]{x1D6E4}$ in $\operatorname{Aff}(X/Y)$ is a virtually solvable group, where $p_{\text{a}}:\operatorname{Aff}(X)\rightarrow \operatorname{Aut}(X)$ is the canonical projection. When $\unicode[STIX]{x1D6E4}$ is finitely generated or when $X$ is the $a$-adic solenoid for an integer $a\geq 1$, the subsolenoid $Y$ can be chosen so that the image $\unicode[STIX]{x1D6E4}$ in $\operatorname{Aff}(X/Y)$ is a virtually abelian group. In particular, an action $\unicode[STIX]{x1D6E4}\curvearrowright (X,\unicode[STIX]{x1D707})$ by affine transformations on a solenoid $X$ has the spectral gap property if and only if $\unicode[STIX]{x1D6E4}\curvearrowright (X,\unicode[STIX]{x1D707})$ is strongly ergodic.
EDITORIAL
Authors: Campbell Marilyn
Published: October 2018

Well, I am delighted. Someone actually emailed me to say they had read the last editorial!!! AND we have two practitioner papers for the issue with another two in the system. Great news on both counts.
A review of coupling mechanism designs for modular reconfigurable robots
Authors: Saab Wael , Racioppo Peter , Ben-Tzvi Pinhas
Published: October 2018

With the increasing demands for versatile robotic platforms capable of performing a variety of tasks in diverse and uncertain environments, the needs for adaptable robotic structures have been on the rise. These requirements have led to the development of modular reconfigurable robotic systems that are composed of a numerous self-sufficient modules. Each module is capable of establishing rigid connections between multiple modules to form new structures that enable new functionalities. This allows the system to adapt to unknown tasks and environments. In such structures, coupling between modules is of crucial importance to the overall functionality of the system. Over the last two decades, researchers in the field of modular reconfigurable robotics have developed novel coupling mechanisms intended to establish rigid and robust connections, while enhancing system autonomy and reconfigurability. In this paper, we review research contributions related to robotic coupling mechanism designs, with the aim of outlining current progress and identifying key challenges and opportunities that lay ahead. By presenting notable design approaches to coupling mechanisms and the most relevant efforts at addressing the challenges of sensorization, misalignment tolerance, and autonomous reconfiguration, we hope to provide a useful starting point for further research into the field of modular reconfigurable robotics and other applications of robotic coupling.
An Evidence Based Approach to the First Unprovoked Seizure
Authors: Wiebe Samuel
Published: October 2018

The objective is to illustrate the creation and structure of a particular type of Evidence Based Care (EBC) summary that has direct clinical relevance, the Critically Appraised Topic (CAT). The process consists of a step-by-step application of the EBC principles to a common neurological problem, ie., a patient presenting with a first, unprovoked generalized seizure. This includes asking a focused clinical question about prognosis for recurrence and the role of antiepileptic drugs; searching the literature to answer the question; selecting the relevant evidence (a meta-analysis about prognosis and a randomized controlled trial about therapy); appraising the literature for its validity and usefulness; and applying the results to the clinical scenario. The result is a one-page, user friendly CAT whose title states a declarative answer to the clinical question. It also contains a description of the literature search and of the evidence, the clinical bottom lines derived from the evidence, and general comments.
The Impact of Aging on Vasa Nervorum, Nerve Blood Flow and Vasopressin Responsiveness
Authors: Kihara Mikihiro , Shioyama Mitsuaki , Okuda Kazuto , Takahashi Mitsuo
Published: October 2018

Objective:

Aging impacts microvessels in a number of tissue beds. Vasopressin acts as a vasoconstrictor in most blood vessels but may also cause vasodilation. We evaluated the role of aging and vasopressin in the regulation of nerve blood flow (NBF) in rat peripheral nerve.

Methods:

We undertook a dose-response study to examine the impact of aging on resting NBF and its vasoreactivity to vasopressin. Nerve blood flow was measured using microelectrode hydrogen polarography. Argininevasopressin was administered both intra-arterially and topically.

Results:

In young adult rats (two months old) topical epineurial application of arginine-vasopressin produced a concentration-dependent reduction of NBF (ED50= 3.8 X 10-5 mol/L). Intra-arterial arginine-vasopressin also reduced NBF. Nerve blood flow was lower in aged rats (12 months old) and less responsive to topically applied vasopressin. The aging group had significantly higher concentrations of vasopressin in plasma than did the younger group.

Conclusions:

The results suggest that vasopressin constricts vessels in peripheral nerve and that there is an age related decline in the vasoconstrictive response to vasopressin. There may be a reduction in receptor sensitivity in vascular smooth muscle cells in peripheral nerve with increasing age.