bluuebunny/crossref_metadata_2025 huggingface dataset:
The RNA genome of hepatitis E virus robustly triggers an antiviral interferon response
Authors: Wang Wenshi , Wang Yijin , Qu Changbo , Wang Shan , Zhou Jianhua , Cao Wanlu , Xu Lei , Ma Buyun , Hakim Mohamad S. , Yin Yuebang , Li Tiancheng , Peppelenbosch Maikel P. , Zhao Jingmin , Pan Qiuwei
Published: December 2017

The outcomes of hepatitis E virus (HEV) infection are diverse, ranging from asymptomatic carrier, self‐limiting acute infection, and fulminant hepatitis to persistent infection. This is closely associated with the immunological status of the host. This study aimed to understand the innate cellular immunity as the first‐line defense mechanism in response to HEV infection. Phosphorylation of signal transducer and activator of transcription 1, a hallmark of the activation of antiviral interferon (IFN) response, was observed in the liver tissues of the majority of HEV‐infected patients but not in the liver of uninfected individuals. In cultured cell lines and primary liver organoids, we found that HEV RNA genome potently induced IFN production and antiviral response. This mechanism is conserved among different HEV strains, including genotypes 1, 3, and 7 as tested. Interestingly, single‐stranded HEV RNA is sufficient to trigger the antiviral response, without the requirement of viral RNA synthesis and the generation of an RNA replicative form or replicative intermediate. Surprisingly, the m7G cap and poly A tail are not required, although both are key features of the HEV genome. Mechanistically, this antiviral response occurs in a retinoic acid–inducible gene‐I–independent, melanoma differentiation–associated protein 5–independent, mitochondrial antiviral signaling protein–independent, and β‐catenin‐independent but IRF3‐dependent and IRF7‐dependent manner. Furthermore, the integrity of the Janus kinase–signal transducer and activator of transcription pathway is essentially required. Conclusion: HEV infection elicits an active IFN‐related antiviral response in vitro and in patients, triggered by the viral RNA and mediated by IFN regulatory factors 3 and 7 and the Janus kinase–signal transducer and activator of transcription cascade; these findings have revealed new insights into HEV–host interactions and provided the basis for understanding the pathogenesis and outcome of HEV infection. (Hepatology 2018;67:2096‐2112).
Multimodal sensor medical image fusion based on mutual‐structure for joint filtering using sparse representation
Authors: Li Weisheng , Xu Xiaofan , Du Jiao
Published: December 2017

Multimodal sensor medical image fusion has been widely reported in recent years, but the fused image by the existing methods introduces low contrast information and little detail information. To overcome this problem, the new image fusion method is proposed based on mutual‐structure for joint filtering and sparse representation in this article. First, the source image is decomposed into a series of detail images and coarse images by mutual‐structure for joint filtering. Second, sparse representation is adopted to fuse coarse images and then local contrast is applied for fusing detail images. Finally, the fused image is reconstructed by the addition of the fused coarse images and the fused detail images. By experimental results, the proposed method shows the best performance on preserving detail information and contrast information in the views of subjective and objective evaluations.
Adsorption of Procion Red MX‐5B and Crystal Violet Dyes from Aqueous Solution onto Corncob Activated Carbon
Authors: Nazifa Tasnia Hassan , Habba Nurmia , Salmiati  , Aris Azmi , Hadibarata Tony
Published: December 2017

Textile and dyeing industries are considered as one of the main water utilizing industries and generate a huge amount of colored liquid effluents in their finishing and dyeing processes. In this paper, agricultural waste corncob has been chosen as a renewable source to produce activated carbon at 400 °C (corncob activated carbon, CCAC) for the removal of Procion Red MX‐5B (PR) and crystal violet (CV) from dye‐polluted effluent using a batch technique. The efficiency of CCAC in adsorbing CV and PR from the water has been carried out as a function of pH, adsorbent dose, contact time, agitation, and initial concentration. The Temkin, Langmuir, and Freundlich isotherm model equations were investigated to understand the adsorption mechanism of dye molecules. The Langmuir isotherm R2 obtained was 0.9958 for CV and 0.9733 for PR. Maximum adsorption capacity obtained was 2.498 mg/g for CV and 2.86 mg/g for PR. Moreover, a pseudo‐second‐order kinetic equation with R2 value of 0.9999 was found in this adsorption process. To identify the chemical and morphological characteristics and surface functional groups, nanocomposite of CCAC was characterized using field emission scanning electron microscopy and Fourier‐transform infrared spectrophotometry. The obtained results indicate that the prepared CCAC can be used as a promising low‐cost dye (CV and PR) removing adsorbent from aqueous solutions.
Using the Connectivity Map to discover compounds influencing human osteoblast differentiation
Authors: Brum Andrea M. , van de Peppel Jeroen , Nguyen Linh , Aliev Abidin , Schreuders‐Koedam Marijke , Gajadien Tarini , van der Leije Cindy S. , van Kerkwijk Anke , Eijken Marco , van Leeuwen Johannes P.T.M. , van der Eerden B C. J.
Published: December 2017

Osteoporosis is a common skeletal disorder characterized by low bone mass leading to increased bone fragility and fracture susceptibility. Identification of factors influencing osteoblast differentiation and bone formation is very important. Previously, we identified parbendazole to be a novel compound that stimulates osteogenic differentiation of human mesenchymal stromal cells (hMSCs), using gene expression profiling and bioinformatic analyzes, including the Connectivity Map (CMap), as an in‐silico approach. The aim for this paper is to identify additional compounds affecting osteoblast differentiation using the CMap. Gene expression profiling was performed on hMSCs differentiated to osteoblasts using Illumina microarrays. Our osteoblast gene signature, the top regulated genes 6 hr after induction by dexamethasone, was uploaded into CMap (www.broadinstitute.org/cmap/). Through this approach we identified compounds with gene signatures positively correlating (withaferin‐A, calcium folinate, amylocaine) or negatively correlating (salbutamol, metaraminol, diprophylline) to our osteoblast gene signature. All positively correlating compounds stimulated osteogenic differentiation, as indicated by increased mineralization compared to control treated cells. One of three negatively correlating compounds, salbutamol, inhibited dexamethasone‐induced osteoblastic differentiation, while the other two had no effect. Based on gene expression data of withaferin‐A and salbutamol, we identified HMOX1 and STC1 as being strongly differentially expressed . shRNA knockdown of HMOX1 or STC1 in hMSCs inhibited osteoblast differentiation. These results confirm that the CMap is a powerful approach to identify positively compounds that stimulate osteogenesis of hMSCs, and through this approach we can identify genes that play an important role in osteoblast differentiation and could be targets for novel bone anabolic therapies.
TGFβ signaling controls intrahepatic bile duct development may through regulating the Jagged1‐Notch‐Sox9 signaling axis
Authors: Wang Wei , Feng Yuan , Aimaiti Yasen , Jin Xin , Mao Xixian , Li Dewei
Published: December 2017

Due to the inherent limitations of the mouse models, the molecular mechanism of TGFβ signaling involved in the development of intrahepatic bile ducts (IHBDs) has been investigated little. Here, we investigated the role of TGFβ signaling and its regulatory mechanism in IHBDs development. We demonstrate that TGFβ signaling pathway activity is essential for IHBDs development. When blocking TGFβ signaling at E10.5, the number of bile ducts in hilum was reduced more than two fold and number of CK19 positive chlangiocytes in periphery was reduced more than 3.5‐fold compared with controls. We also show that alpha‐smooth muscle actin (α‐SMA)‐immunoreactive cells are located in the portal vein mesenchyme (PVM) adjacent to the bile ducts during IHBDs development and identify the α‐SMA positive cells expressing the Notch ligand Jagged1 in the periportal area. Importantly, after blocking TGFβ signaling, the expression of Jagged1 was selectively decreased in the PVM but not in biliary epithelial cells (BECs), which is associated with the transformation of portal mesenchyme cells (PMCs) into portal myofibroblasts (PMFs). In addition, Sox9, which is downstream of Notch, is decreased after blocking the TGFβ signaling pathway in the liver. Our findings uncover a novel mechanism of TGFβ signaling in controlling the development of IHBDs may through regulating the Jagged1‐Notch‐Sox9 signaling axis.
Strike kinematics and performance in juvenile ball pythons (Python regius)
Authors: Ryerson William G , Tan Weimin
Published: December 2017

The rapid strike of snakes has interested researchers for decades. Although most work has focused on the strike performance of vipers, recent work has shown that other snakes outside of the Viperidae can strike with the same velocities and accelerations. However, to date all of these examples focus on performance in adult snakes. Here, we use high‐speed video to measure the strike kinematics and performance of 10 juvenile (<6 months of age) ball pythons,Python regius. We find that juvenileP. regiusstrike at levels comparable to larger snakes, but with shorter durations and over shorter distances. We conclude that the juvenileP. regiusmaintain performance likely through manipulation of the axial musculature and accompanying elastic tissues, and that this is a first step to understanding ontogenetic changes in behavior and a potential avenue for understanding how captivity may also impact behavior.
HIV viral load monitoring among key populations in low‐ and middle‐income countries: challenges and opportunities
Authors: Schwartz Sheree R , Kavanagh Matthew M , Sugarman Jeremy , Solomon Sunil S , Njindam Illiassou M , Rebe Kevin , Quinn Thomas C , Toure‐Kane Coumba , Beyrer Chris , Baral Stefan
Published: December 2017

Introduction

Key populations bear a disproportionate HIV burden and have substantial unmet treatment needs. Routine viral load monitoring represents the gold standard for assessing treatment response at the individual and programme levels; at the population‐level, community viral load is a metric of HIV programme effectiveness and can identify “hotspots” of HIV transmission. Nevertheless, there are specific implementation and ethical challenges to effectively operationalize and meaningfully interpret viral load data at the community level among these often marginalized populations.

Discussion

Viral load monitoring enhances HIV treatment, and programme evaluation, and offers a better understanding of HIV surveillance and epidemic trends. Programmatically, viral load monitoring can provide data related to HIV service delivery coverage and quality, as well as inequities in treatment access and uptake. From a population perspective, community viral load data provides information on HIV transmission risk. Furthermore, viral load data can be used as an advocacy tool to demonstrate differences in service delivery and to promote allocation of resources to disproportionately affected key populations and communities with suboptimal health outcomes. However, in order to perform viral load monitoring for individual and programme benefit, health surveillance and advocacy purposes, careful consideration must be given to how such key population programmes are designed and implemented. For example, HIV risk factors, such as particular sex practices, sex work and drug use, are stigmatized or even criminalized in many contexts. Consequently, efforts must be taken so that routine viral load monitoring among marginalized populations does not cause inadvertent harm. Furthermore, given the challenges of reaching representative samples of key populations, significant attention to meaningful recruitment, decentralization of care and interpretation of results is needed. Finally, improving the interoperability of health systems through judicious use of biometrics or identifiers when confidentiality can be maintained is important to generate more valuable data to inform monitoring programmes.

Conclusions

Opportunities for expanded viral load monitoring could and should benefit all those affected by HIV, including key populations. The promise of the increasing routinization of viral load monitoring as a tool to advance HIV treatment equity is great and should be prioritized and appropriately implemented within key population programmatic and research agendas.
Scaling up HIV viral load – lessons from the large‐scale implementation of HIV early infant diagnosis and CD4 testing
Authors: Peter Trevor , Zeh Clement , Katz Zachary , Elbireer Ali , Alemayehu Bereket , Vojnov Lara , Costa Alex , Doi Naoko , Jani Ilesh
Published: December 2017

Introduction

The scale‐up of effective HIV viral load (VL) testing is an urgent public health priority. Implementation of testing is supported by the availability of accurate, nucleic acid based laboratory and point‐of‐care (POC) VL technologies and strong WHO guidance recommending routine testing to identify treatment failure. However, test implementation faces challenges related to the developing health systems in many low‐resource countries. The purpose of this commentary is to review the challenges and solutions from the large‐scale implementation of other diagnostic tests, namely nucleic‐acid based early infant HIV diagnosis (EID) and CD4 testing, and identify key lessons to inform the scale‐up of VL.

Discussion

Experience with EID and CD4 testing provides many key lessons to inform VL implementation and may enable more effective and rapid scale‐up. The primary lessons from earlier implementation efforts are to strengthen linkage to clinical care after testing, and to improve the efficiency of testing. Opportunities to improve linkage include data systems to support the follow‐up of patients through the cascade of care and test delivery, rapid sample referral networks, and POC tests. Opportunities to increase testing efficiency include improvements to procurement and supply chain practices, well connected tiered laboratory networks with rational deployment of test capacity across different levels of health services, routine resource mapping and mobilization to ensure adequate resources for testing programs, and improved operational and quality management of testing services. If applied to VL testing programs, these approaches could help improve the impact of VL on ART failure management and patient outcomes, reduce overall costs and help ensure the sustainable access to reduced pricing for test commodities, as well as improve supportive health systems such as efficient, and more rigorous quality assurance. These lessons draw from traditional laboratory practices as well as fields such as logistics, operations management and business.

Conclusions

The lessons and innovations from large‐scale EID and CD4 programs described here can be adapted to inform more effective scale‐up approaches for VL. They demonstrate that an integrated approach to health system strengthening focusing on key levers for test access such as data systems, supply efficiencies and network management. They also highlight the challenges with implementation and the need for more innovative approaches and effective partnerships to achieve equitable and cost‐effective test access.
Intraspecific variation in the domestic cat bony labyrinth revealed by different measurement techniques
Authors: Schellhorn Rico
Published: December 2017

The knowledge of intraspecific variation is important to make assumptions on an interspecific level. To study intraspecific variation in the bony labyrinth morphology of the domestic cat, eleven specimens of Felis silvestris catus and two additional subspecies (F. s. lybica, F. s. ornata) were investigated. The sample comprises skulls of adult males and females, as well as juvenile cats. Each bony labyrinth endocast was virtually reconstructed based on µCT scans. To estimate the radius of curvature of each inner ear semicircular canal, three different approaches were tested. The comparison of the different methods resulted in different absolute values for the measured radii. The assumed best structure to precisely characterize the size of a semicircular canal is the inner perimeter. Within the tested sample, the anterior semicircular canal is always the largest, while the posterior semicircular canal is the second largest and the lateral semicircular canal the smallest in most cases. The coefficient of variation lies below 10% for all bony labyrinth measurements within the sample. The inner perimeter values of each semicircular canal are similar within all investigated specimens, even though the skull length of adult cats is twice as long as that of juvenile cats. Thus, inner ear biometry of the domestic cat seems stable throughout growth series and can therefore be used for systematic and ecological studies and the inclusion of juvenile individuals is reasonable. It is noteworthy that the inner perimeter values of the semicircular canals do not vary as much as the values of the angles spanned between the three canals within the sample. The inner ear within the cat skull is oriented about 25° to 31° to the palate (angle between the plane anchored to the lateral semicircular canals (SC) and the plane anchored to the palate). The cochlea coils between 3.00 and 3.25 turns in the investigated sample.
Links between the discovery of primates and anatomical comparisons with humans, the chain of being, our place in nature, and racism
Authors: Diogo Rui
Published: December 2017

I focus on the crucial links between the discovery of nonhuman primates by Westerners, discussions on our place in nature, the chain of being, racism, and the history of primate comparative anatomy and of so‐called “anatomical human racial studies.” Strikingly, for more than a millennium humans knew more about the internal anatomy of a single monkey species than about that of their own bodies. This is because Galen used monkeys to infer human anatomy, in line with the human‐animal continuity implied by the Greek notion of scala naturae. With the rise of Christianity, nonhuman primates were increasingly seen in a negative way. A more positive view emerged in the 14th century when nonhuman primates were directly studied/seen by Europeans, culminating in Tyson's 1699 work showing that chimps share more gross anatomical similarities with humans than with monkeys. However, the discomfort caused by this human‐chimp similarity then led to a new idea of animal‐human discontinuity, now related not to anatomy but to “civilization”: between Europeans vs. non‐Europeans + other primates. Moreover, Linnaeus' Systema Naturae and the emergence of “anatomical racial studies” influenced by Camper's craniology then led to even more extreme ideas, such as the notion that Europeans were both mentally and morphologically “ideal.” Unfortunately the biased and often incorrect “results” of such studies, combined with ideas based on Darwin's “struggle for survival”, became crucial in propaganda that lead to the rise of eugenics in the end of the 19th/first half of 20th centuries and that culminated in Nazism. Since the 1950s there has been an emphasis on the continuity/unity between all human groups and other primates, in great part influenced by what happened during World War 2. Reviews such as this one are, therefore, particularly necessary to illuminate and guard against attitudes against “the Other” and racist ideologies that are re‐emerging in modern political discourse across the globe.
Raman microspectroscopy of blue‐green historical beads: Comparative study of undamaged and strongly degraded samples
Authors: Balakhnina I.A. , Brandt N.N. , Chikishev A.Y. , Mankova A.A. , Morozova E.A. , Shpachenko I.G. , Yuryev V.A. , Yuryeva T.V.
Published: December 2017

Confocal Raman microspectroscopy is used to substantially supplement existing experimental data on historical blue‐green beads with respect to the presence and distribution of potassium antimony silicate (KSS) crystals. Problem of degradation of blue‐green beads on historical artifacts accounts for topicality of the work. The reasons for possible short‐term (several years) degradation of beads and the presence of neighboring damaged and undamaged beads on a single item remain unknown in spite of multiple experimental works on various glasses. Presence of KSS microcrystals may serve as a reason for degradation of beads. Raman measurements at several depths are used to determine the distribution and estimate sizes of KSS microcrystals. Such distributions are different for undamaged and strongly degraded beads. For degraded beads, Raman data show the depth dependence of the concentration of (non)bridged oxygens in the near‐surface layer with a thickness of 3–4 μm (i.e., inhomogeneity of glass matrix). The results prove the growth of KSS microcrystals in historical blue‐green beads, which may cause internal stress and, hence, degradation. The results can be used for optimization of storage conditions and restoration procedures for historical items.
Antioxidant and anti‐inflammatory activities of freeze‐dried grapefruit phenolics as affected by gum arabic and bamboo fibre addition and microwave pretreatment
Authors: García‐Martínez Eva , Andújar Isabel , Yuste del Carmen Alberto , Prohens Jaime , Martínez‐Navarrete Nuria
Published: December 2017

BACKGROUND

Recent epidemiological studies have suggested that phenolic compounds present in grapefruit play an important role in the bioactive properties of this fruit. However, the consumption of fresh grapefruit is low. Freeze‐dried powdered grapefruit can be an alternative to promote this fruit consumption. To improve the quality and stability of the powdered fruit, encapsulating and anticaking agents can be added. In the present study, different grapefruit powders obtained by freeze‐drying with the addition of gum arabic (1.27 g per 100 g) and bamboo fibre (0.76 g per 100 g) with and without a pre‐drying microwave treatment were compared with the fresh and freeze‐dried fruit with no carriers added, aiming to evaluate the effect of these preservation processes on phenolics content and on its antioxidant [1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) and ferric reducing ability of plasma (FRAP)] and anti‐inflamatory (evaluated in RAW 264.7 macrophages) capacities.

RESULTS

Freeze‐drying and gum arabic and bamboo fibre addition significantly increased total phenolics, as well as the antioxidant and anti‐inflammatory activities (by inhibiting nitric oxide production of lipopolysaccharide activated RAW 264.7 macrophages), of grapefruit. An additional increase in these parameters was obtained with microwave pretreatment before freeze‐drying.

CONCLUSIONS

The combined addition of gum arabic and bamboo fibre to grapefruit puree and the application of a microwave pretreatment improve the functional properties of the fruit without showing cytotoxicity in vitro. © 2017 Society of Chemical Industry
Headspace solid‐phase microextraction and gas chromatographic analysis of low‐molecular‐weight sulfur volatiles with pulsed flame photometric detection and quantification by a stable isotope dilution assay
Authors: Ullrich Sebastian , Neef Sylvia K. , Schmarr Hans‐Georg
Published: December 2017

Low‐molecular‐weight volatile sulfur compounds such as thiols, sulfides, disulfides as well as thioacetates cause a sulfidic off‐flavor in wines even at low concentration levels. The proposed analytical method for quantification of these compounds in wine is based on headspace solid‐phase microextraction, followed by gas chromatographic analysis with sulfur‐specific detection using a pulsed flame photometric detector. Robust quantification was achieved via a stable isotope dilution assay using commercial and synthesized deuterated isotopic standards. The necessary chromatographic separation of analytes and isotopic standards benefits from the inverse isotope effect realized on an apolar polydimethylsiloxane stationary phase of increased film thickness. Interferences with sulfur‐specific detection in wine caused by sulfur dioxide were minimized by addition of propanal. The method provides adequate validation data, with good repeatability and limits of detection and quantification. It suits the requirements of wine quality management, allowing the control of oenological treatments to counteract an eventual formation of excessively high concentration of such malodorous compounds.
The promotion of health tourism products for domestic tourists
Authors: Han Ji‐Sook , Lee Timothy J. , Ryu Kisang
Published: December 2017

This study investigates the demand for travel for well‐being and enhancing health by Korean domestic tourists. The current level of health travel preferences and participation rates were examined and compared to the preference for other travel types. A questionnaire survey was conducted with 270 participants, and additional raw data from the Korean National Tourism Survey (a sample of 6,309) were incorporated. This research found that preference for health travel is comparatively high, but participation levels are low compared to other travel themes. From these results, implications for health tourism industry practitioners are suggested, and recommendations for marketing products proposed.
Repeatability of Female Midurethral Measurement Using High‐Frequency 3‐Dimensional Transvaginal Ultrasonography
Authors: Xuan Yinghua , Yue Song , Sun Lijuan , Pei Yan , Wang Jingjing , Tan Li , Lu Zhaoling , Yang Liman , An Yuanyuan , Jiang Yuxin , Wu Qingqing
Published: December 2017

Objectives

Imaging assessment of the female urethra is critical for diagnosis and treatment of urinary incontinence. High‐frequency 3‐dimensional (3D) transvaginal ultrasonography (TVUS) is a novel technique for evaluating the female urethra. The aim of this study was to test the repeatability of 3D TVUS between examiners without prior experience with TVUS.

Methods

Fifty women underwent 3D TVUS. Two examiners without prior experience analyzed the urethral volumes and measured the urethral parameters. Two‐dimensional (2D) parameters included urethral sphincter length and urethral sphincter thickness; 3D parameters included urethral sphincter volume, midurethral complex volume, and inner core volume. One of the examiners repeated the evaluations 1 month later. Subsequently, the measurements were compared.

Results

The mean age of the patients ± SD was 34.1 ± 8.1 (range, 23–55) years; the mean height, weight, and body mass index were 160.44 ± 5.12 (range, 150–173) cm, 61.80 ± 13.64 (range, 45–110) kg, and 23.98 ± 4.91 (range, 17.53–39.92) kg/m2, respectively. The results of our study showed excellent to good intraobserver repeatability (intraclass correlation coefficient [ICC], 0.75–0.87) for the evaluations of all parameters but urethral sphincter length (moderate ICC, 0.53), whereas they showed good to moderate interobserver repeatability (ICC, 0.44–0.77) for all parameters. The repeatability of 3D volumes (ICC, 0.59–0.87) tended to be better than that of 2D parameters (ICC, 0.44–0.76).

Conclusions

The intraobserver and interobserver repeatability of high‐frequency 3D TVUS measurements of the female urethra was excellent to moderate between examiners without previous experience. The repeatability of 3D measurements tended to be better than that of 2D parameters.
The inner‐rod component of Shigella flexneri type 3 secretion system, MxiI, is involved in the transmission of the secretion activation signal by its interaction with MxiC
Authors: El Hajjami Nargisse , Moussa Simon , Houssa Jonathan , Monteyne Daniel , Perez‐Morga David , Botteaux Anne
Published: December 2017

The virulence of Shigella mainly resides in the use of a Type 3 Secretion System (T3SS) to inject several proteins inside the host cell. Three categories of proteins are hierarchically secreted: (1) the needle components (MxiH and MxiI), (2) the translocator proteins which form a pore (translocon) inside the host cell membrane, and (3) the effectors interfering with the host cell signaling pathways. In the absence of host cell contact, the T3SS is maintained in an “off” state by the presence of a tip complex. We have previously identified a gatekeeper protein, MxiC, which sequesters effectors inside the bacteria probably by interacting with MxiI, the inner‐rod component. Upon cell contact and translocon insertion, a signal is most likely transmitted from the top of the needle to the base, passing through the needle and allowing effectors release. However, the molecular mechanism underlying the transmission of the activation signal through the needle is still poorly understood. In this work, we investigate the role of MxiI in the activation of the T3SS by performing a mutational study. Interestingly we have shown that mutations of a single residue in MxiI (T82) induce an mxiC‐like phenotype and prevent the interaction with MxiC. Moreover, we have shown that the L26A mutation significantly reduces T3 secretion. The L26A mutation impairs the interaction between MxiI and Spa40, a keystone component of the switch between needle assembly and translocators secretion. The L26A mutation also sequesters MxiC. All these results highlight the crucial role of MxiI in regulating the secretion and transmitting the activation signal of the T3SS.
Nowcasting algorithm for wind fields using ensemble forecasting and aircraft flight data
Authors: Kikuchi Ryota , Misaka Takashi , Obayashi Shigeru , Inokuchi Hamaki , Oikawa Hiroshi , Misumi Akeo
Published: December 2017

This study proposes an algorithm that combines ensemble numerical weather‐prediction model data and aircraft flight data in a wind nowcasting system for safe and efficient aircraft operation. It uses an ensemble‐weighted average method based on sequential importance sampling (SIS), which is a particle filter method for forecasting the wind field in real time. SIS is applied to the ensemble forecast data and control run data of the European Centre for Medium‐Range Weather Forecasts (ECMWF), Japan Meteorological Agency (JMA), Korea Meteorological Administration (KMA), National Centers for Environmental Prediction (NCEP) and United Kingdom Met Office (UKMO) for the two case studies that use flight data from 72 commercial aircraft flights. The results show that SIS can forecast better than the other four methods: direct ensemble average (DEA), elite strategy (ES), and selective ensemble average (SEAV) and weighted average (SEWE), with average improvements in forecast performance of about 10–15%, even at 300 min ahead. In addition, the overall forecast performance between the forecast wind and observation of the radiosonde of SIS was slightly better than DEA. In both cases, the forecast performance was significantly improved on points along the flight path of the aircraft used for this study. Case analyses and the impact of differences in the hyper‐parameters of SIS on forecast performance are also presented in this study.
Numerical solution of nonlinear stochastic Itô‐Volterra integral equations driven by fractional Brownian motion
Authors: Mirzaee Farshid , Samadyar Nasrin
Published: December 2017

In this paper, an efficient numerical technique is applied to provide the approximate solution of nonlinear stochastic Itô‐Volterra integral equations driven by fractional Brownian motion with Hurst parameter
. The proposed method is based on the operational matrices of modification of hat functions (MHFs) and the collocation method. In this approach, by approximating functions that appear in the integral equation by MHFs and using Newton's‐Cotes points, nonlinear integral equation is transformed to nonlinear system of algebraic equations. This nonlinear system is solved by using Newton's numerical method, and the approximate solution of integral equation is achieved. Some theorems related to error estimate and convergence analysis of the suggested scheme are also established. Finally, 2 illustrative examples are included to confirm applicability, efficiency, and accuracy of the proposed method. It should be noted that this scheme can be used to solve other appropriate problems, but some modifications are required.
Dual‐/triple‐wideband microstrip bandpass filter using independent triple‐mode stub‐loaded resonator
Authors: Wang Z. J. , Wang C. , Kim N. Y.
Published: December 2017

A dual‐wideband and a triple‐wideband microstrip bandpass filters (BPFs) using independent triple‐mode stub‐loaded resonators are presented in this letter. The resonator consists of a half‐wavelength transmission line, which resonates at the first resonant mode, and two identical quarter‐wavelength loaded stubs generating the other two resonant modes. The dimensional adjustments of a particular resonator only affect itself without influencing the other two resonators, which results in good independent property. The measurement results verify that the fabricated dual‐wideband BPF possesses the central frequencies of 2.39 GHz (return loss: 18.2 dB) and 5.13 GHz (return loss: 30.1 dB), and the fractional bandwidth (FBW) of 16.2% (insertion loss: 0.25 dB) and 16.6% (insertion loss: 0.31 dB) were obtained. For the fabricated triple‐wideband BPF, the FBW was 16.7% (insertion loss: 0.24 dB) at 2.50 GHz (return loss: 22.8 dB), 14.4% (insertion loss: 0.33 dB) at 3.68 GHz (return loss: 19.7 dB), and 13.2% (insertion loss: 0.40 dB) at 5.04 GHz (return loss: 21.5 dB).
Wide stopband miniaturized “I”‐typed EBG with DGS
Authors: Rong Hongying , Wang Qian , Chen Shuo , Cao Yajie , Tian Huiping
Published: December 2017

An electromagnetic band‐gap (EBG) structure which combines a tapered surface structure and a tapered defected ground structure is proposed in this article. “I”‐typed EBG units with different size and center distance are etched on the microstrip line on the upper layer of the substrate. Without sacrificing the bandwidth, a feasible method is proposed to implement miniaturization by reducing the second half of the tapered EBG, which is concluded by analyzing the relations between the working frequency and tapered periodic structure. By using HFSS simulation tool, the proposed structure possesses a wide stop‐band of 23.72 GHz (1.88–29.20 GHz). Particularly, the actual size characteristic is only about 40 × 20 × 0.6 mm3. Meanwhile, the proposed structure is fabricated and measured. And the experimental results basically agree well with the simulated results, which indicate that the proposed EBG is promising for designing high performance band‐stop filters and associated antennas with width bandwidth and small size.
A compact UWB patch antenna with defected ground for Ku/K band applications
Authors: Mishra Brijesh , Singh Vivek , Singh Rakesh Kumar , Singh Neha , Singh Rajeev
Published: December 2017

The term “ultrawideband” (UWB) in antenna research has become a buzzword over the past decade. In recent years, advancement in this new area has given birth to numerous antenna designs. A simple and practical method to design an ultra‐wideband microstrip antenna is presented. The overall dimension of the proposed ultra‐wideband antenna is (20 × 20) mm2 and it consists of a defected ground along with the two layers stacking. The proposed is operating between 11.97 and 20.54 GHz which covers both downlink and uplink frequencies of Ku band and partially K band (2.54 GHz).The modeling and simulation is performed using Ansoft HFSS (High Frequency Structural Simulator) software. This proposed prototype achieves the peak gain of 8.5 dBi and maximum radiation efficiency of 88.5%.
Modeling of yield, slope efficiency, and spectra of multisegment distributed feedback lasers
Authors: Kim Hong , Khinda Gurvinder , Jules Jonathan D. , Klotzkin David
Published: December 2017

The properties and yield of a distributed feedback laser depends on the values of coupling coefficient κ and many other parameters. Multisegmented distributed feedback devices (consisting of grated and ungrated areas, quarter‐wave‐shifts, and potentially other features other) are becoming more common and have advantages over uniform grated devices. A multi‐segmented transfer matrix model is used to model the spectra, yield, and slope efficiency of multisegment and uniform distributed feedback lasers. The results give an excellent match to measured spectra of partially grated, quarter‐wave‐shifted, and uniform devices, and qualitatively agree with experimental data on the distribution of slope efficiency in devices. A study on partial grated devices suggested they may have advantages in single mode yield compared to uniformly grated devices. This method (and the specific software tool Glaparex) can be used to control device parameters in manufacturing and to optimize laser designs design.
Gigabit LED‐based visible light transparent transmission from free‐space to a 100‐m ultra‐large effective area pure silica fiber
Authors: Shi Jianyang , Zhou Yingjun , Chi Nan , Xiong Liangming , Luo Jie
Published: December 2017

We experimentally demonstrate the LED‐based visible light transmission (VLC) over a 100‐m special designed low‐loss ultra‐large effective area (diameter >1 mm) pure silica fiber (ULEAPS fiber). Three‐channel wavelength multiplexing is achieved by using a single chip RGB LED as the light source. The total insertion loss after 100‐meter transmission for the red light, green light and blue light are 1.015, 1.582, and 3.660 dB, respectively. A total data rate of 3.1 Gb s−1 is experimentally achieved over 5‐m ULEAPS fiber and a data rate of 2 Gb s−1 is achieved over 100‐m fiber with the bit error rate (BER) below 7% forward error correction (FEC) limit of 3.8 × 10−3. The results obtained here may also serve as a valuable information on how to realize LED based VLC transparent transmission from free‐space to a pure silica fiber utilizing a commercial illumination LED as the light source.
Semi‐transparent frequency reconfigurable antenna with DGS
Authors: Lim M.C. , Rahim S.K.A. , Hamid M.R. , Soh P.J. , Eteng Aa
Published: December 2017

In this letter, a semi‐transparent frequency reconfigurable antenna is proposed and investigated. This antenna is implemented on glass as a substrate, AgHT‐4 as a radiating element and copper as its ground plane to result in a semi‐transparent feature. A pair of PIN diodes is utilized as microwave switches along with a DC biasing circuit. This proposed antenna is fed by a CPW arrangement and introduces unequal E‐shaped Defected Ground Structure (DGS) on the ground plane for modification of the electrical length. The antenna exhibits a −10 dB impedance bandwidth from 3 to 6 GHz when PIN diodes are ON, and a resonance at 4.75 GHz when pin diodes are OFF. The proposed antenna is fabricated to validate its performance in terms of reflection coefficient and radiation pattern.
Compact planar 2 × 2 and 4 × 4 UWB mimo antenna arrays for portable wireless devices
Authors: Sipal Deepika , Abegaonkar Mahesh. P. , Koul Shiban K.
Published: December 2017

A very compact 2 × 2 and 4 × 4 ultra wide band (UWB) multiple input multiple output (MIMO) antenna array with high isolation and polarization/pattern diversity are proposed in this letter. The compact size of antenna with orthogonally polarized elements help in achieving high isolation between elements of the arrays without using any decoupling circuit while maintaining its overall size very compact. The monopole UWB antenna prototype has compact size of 14 × 14 mm2 and enlarged to 2 × 2 array having size of 14 × 31 mm2 and 4 × 4 array having overall size of 31 × 31 mm2. The proposed designs have been fabricated and tested. Measured isolations |S21| are ≤ −25 dB and ≤ −20 dB for 2 × 2 and 4 × 4 arrays, respectively. However, impedance bandwidth |S11| is ≤ −10 dB for both arrays in the range from 3.6 to 10.6 GHz. The simulated, measured and calculated result shows good agreement for its impedance matching, isolation and dual polarization characteristics. Dual polarization improves its diversity performance and compact size improves its spatial multiplexing.
A compact 1:15 unequal Wilkinson power divider using A‐CRLH coupled lines
Authors: Torabi Yalda , Dadashzadeh Gholamreza
Published: December 2017

A novel asymmetric composite right/left‐handed (A‐CRLH) coupled‐line circuit structure for a miniaturized unequal Wilkinson power divider (WPD) with arbitrary large power division ratio and reduced arm's length is proposed. Compared with the traditional unequal WPD, using the A‐CRLH coupled‐line section in the proposed power divider, due to its controllable phase response and characteristic impedances, not only leads to more compact layout but also results in a larger power‐dividing ratio with relaxed line width and separation. The simplified design procedure along with closed form equations based on c‐ and π‐mode analysis and transmission‐line‐based metamaterial theory is derived. For demonstration, a practical A‐CRLH WPD with a high power‐dividing ratio of 1:15 as a typical example, at 1.4 GHz is designed, simulated and fabricated. The occurred area of the implemented power divider is 58.7% smaller than that of the conventional one at the same frequency and its experimental results show good agreement with simulation data.
Time domain characterization of high power solid state amplifiers for the next generation linear accelerators
Authors: Hoang Duc Long , Bhattacharyya Anirban , Goryasko Vitaliy , Ruber Roger , Rydberg Anders , Olsson Jorgen , Dancila Dragos
Published: December 2017

This paper presents the time‐domain characterization of high power pulsed solid state amplifiers to be used for linear accelerator applications. The study comprises nonlinear circuit envelope simulations and time domain envelope measurements. Measurements and simulations are performed under the pulsed conditions (3.5 ms pulse width, 5% duty cycle) specific to the European Spallation Source (ESS) high intensity proton accelerator. We measure the characteristics of pulsed LDMOS based power amplifiers such as: pulse droop along the pulse, efficiency, average envelope pulse amplitude and phase, pulse drain current waveform, pulse drain voltage waveform, etc. A comparison between the measured results and the simulated results is also presented. In addition to the pulse profile characterization, the pulse to pulse (P2P) stability of the presented solid state power amplifier (SSPA) is investigated as variations of amplitude and phase. The P2P stability simulations are introduced as a combination of the Monte‐Carlo simulations and the nonlinear circuit envelope simulations. The simulated results are used for fitting the P2P measurements to give an early insight of causes of instabilities of the nonlinear LDMOS models.
Compact wide triband multicavity‐coupled slot antenna
Authors: Li Wei‐Wen , Su Jin‐Sheng , Zhou Jian‐Hua , Shi Zhi‐Yuan
Published: December 2017

In this letter, we propose a triband slot antenna with additional slots directly connected to an original slot radiator. The proposed antenna has been halved to reduce the antenna size. The experimental results show that this antenna can operate in three bands of 2.38–2.58 GHz, 3.34–3.85 GHz, and 5.07–5.60 GHz, respectively. Meanwhile, the parameter analysis has indicated that each band works according to the cavity‐coupled mode, which can enlarge the bandwidth and enhance the stability of radiating patterns in the corresponding bands.
Modalmetric interferometer under Fingerprint disturbances: The effect of lateral offset between the single‐mode and multimode fiber splice
Authors: Ribeiro Ricardo M. , Balod Yanes C.
Published: December 2017

We report on the wavelength and time‐domain responses of a lumped or distributed fiber‐optic modalmetric interferometer under a very smooth pressure (fingerprint) disturbances in the 1530–1610 nm wavelength range. A simple method to quantify such disturbances is proposed. It is shown that the lateral offset shift of 5.9 mm between the single‐mode and the multimode fiber splice makes the device even more sensitive. It was measured an electrical signal power enhancements of 3.5 and 7.5 dB for 1 m and 1.65 km multimode fiber link, respectively.
A novel miniaturized UWB monopole with five‐section stepped‐impedance feed line
Authors: Ul Haq Muhammad Aziz , Koziel Slawomir
Published: December 2017

A structure and design procedure of a compact ultra‐wideband (UWB) monopole antenna is proposed. In order to achieve additional size reduction, a modified‐shape feed line and a five‐section rectangular slit below the feed line is incorporated into a reference antenna featuring a two‐section rectangular slit below the feed line and two radiator slots. The minimum‐size is obtained by adjustment of all geometry parameters of the structure using rigorous numerical optimization. An explicit constraint on antenna reflection characteristic is imposed in order to ensure sufficient matching in the entire UWB frequency range. The footprint area of the final design is only 167 mm2 with antenna dimensions of 22.46 mm × 7.45 mm. Experimental validation confirms good electrical and field properties. Thorough benchmarking indicates that the proposed antenna is competitive to recently reported designs.
A high FoM monopole antenna with asymmetrical L‐slots for WiMAX and WLAN applications
Authors: Gangwar A. , Alam M. S.
Published: December 2017

A triband monopole patch antenna with high figure‐of‐merit (FoM) for WiMAX and WLAN applications has been proposed. It consists of a rectangular patch with two asymmetrical L‐shaped slots, where L‐slots generate two lower resonance frequencies and patch the higher. A parametric study to optimize the slot length is carried out to achieve the desired frequency bands. An equivalent circuit model of the antenna is developed and analyzed for loss due to input impedance mismatch at each resonance frequency. The simulated results of return loss of antenna and radiation patterns are validated with experimental results.
Demonstration of negative refractive index with low‐cost inkjet‐printed microwave metamaterials
Authors: İbili Hande , Karaosmanoğlu Barışcan , Ergül Özgür
Published: December 2017

We present low‐cost fabrications of inkjet‐printed metamaterials that are resonating at microwave frequencies. A very low‐cost setup involving commercial desktop printers loaded with silver‐based inks is constructed and used to fabricate the metamaterials. We show that, despite the challenges in the low‐cost fabrication processes, successful prints, and metamaterial samples can be obtained. A composite metamaterial design, which possesses a bandlimited transparency due to the induced negative refractive index, is fabricated and tested to demonstrate the feasibility of low‐cost metamaterials with relatively complex geometries involving three‐dimensional arrangements.
Antipodal Vivaldi antennas with foldable hinged plates for adaptive polarization and gain adjustments
Authors: Byun G. , Lim T. H. , Kang M. C. , Choo H.
Published: December 2017

This letter proposes a novel approach to adaptive polarization and gain adjustments for antipodal Vivaldi antennas using foldable hinged plates. The proposed antenna consists of upper and lower flared wings, and the wings are electrically extended using two rectangular plates. Metal hinges are then adopted to fold and unfold the plates, which allows the antenna to adjust the polarization in the entire range of the axial ratio and to further enhance the gain in the end‐fire direction. Measured antenna characteristics demonstrate that the polarization and the gains are adaptively adjusted by varying the tilt angles of the hinged plates without a distortion of the broadband properties.
A broadband U‐shaped patch antenna on PTFE/Cu substrate for 60 GHz wireless communications
Authors: Adane Amar , Person Christian , Gallee François
Published: December 2017

A U‐shaped antenna is printed on polytetrafluoroethylene film, deposited on a copper base having air cavity inside, using thin film micro‐strip technology. This antenna is as compact as the rectangular patch and covers the 51.5–62 GHz band. Unlike the silicon substrate, its metallic support yields better radiation patterns.