bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of high-risk carbapenem-resistant Klebsiella pneumoniae and Enterobacter cloacae isolates using volatile molecular profiles
Authors: Rees Christiaan A. , Nasir Mavra , Smolinska Agnieszka , Lewis Alexa E. , Kane Katherine R. , Kossmann Shannon E. , Sezer Orkan , Zucchi Paola C. , Doi Yohei , Hirsch Elizabeth B. , Hill Jane E.
Published: August 2018

Infections caused by carbapenem-resistantEnterobacteriaceae(CRE) are alarming in the clinical setting, as CRE isolates often exhibit resistance to most clinically-available antibiotics.Klebsiella pneumoniaecarbapenemase (KPC) is the most common carbapenemase carried by CRE in North America and Europe, frequently detected in isolates ofK.pneumoniae,Escherichia coli, andEnterobacter cloacae. Notably, KPC-expressing strains often arise from clonal lineages, with sequence type 258 (ST258) representing the dominant lineage inK.pneumoniae, ST131 inE.coli, and ST78 and ST171 inE.cloacae. Prior studies have demonstrated that carbapenem-resistantK.pneumoniaediffers from carbapenem-susceptibleK.pneumoniaeat both the transcriptomic and soluble metabolomic levels. In the present study, we sought to determine whether carbapenem-resistant and carbapenem-susceptible isolates ofK.pneumoniae,E.coli, andE.cloacaeproduce distinct volatile metabolic profiles. We were able to identify a volatile metabolic fingerprint that could discriminate between CRE and non-CRE with an area under the receiver operating characteristic curve (AUROC) as high as 0.912. Species-specific AUROCs were as high as 0.988 forK.pneumoniaeand 1.000 forE.cloacae. Paradoxically, curing of KPC-expressing plasmids from a subset ofK.pneumoniaeisolates further accentuated the metabolic differences observed between ST258 and non-ST258.
Expression profiling of ubiquitin-related genes in LKB1 mutant lung adenocarcinoma
Authors: Wang Guanghui , Bie Fenglong , Qu Xiao , Yang Xudong , Liu Shaorui , Wang Yu , Huang Cuicui , Wang Kai , Du Jiajun
Published: August 2018

Liver kinase B1 (LKB1) is a tumor suppressor, and there is a very high proportion of LKB1 mutation in lung adenocarcinoma. The function of LKB1 is closely related to that of ubiquitin related genes. Our objective is to analyze the changes in ubiquitin-related genes in LKB1 mutant lung adenocarcinoma. We searched The Cancer Genome Atlas (TCGA) and obtained gene expression profiles from 230 lung adenocarcinoma patients, which were then analyzed using R software. Kaplan–Meier curves and Cox proportional hazards regression were applied to estimate survival. Real-time reverse transcription PCR was used to verify gene expression. Gene function was explored by gene set enrichment analysis. There were significantly expressed differences in the ubiquitin-related gene SH3RF1 between the LKB1 mutant and wild-type lung adenocarcinoma patients (p = 9.78013E-05). Patients with LKB1 mutation and high expression of SH3RF1 had a better prognosis than the low expression group (HR 0.356, 95% CI 0.136–0.929, p = 0.035). SH3RF1 can influence cell cycle, apoptosis, DNA replication and the p53 signaling pathway. SH3RF1 might have great clinical value act as a diagnostic biomarker and indicator to evaluate the prognosis of LKB1 mutant lung adenocarcinoma patients. This gene also can become a new treatment target for LKB1 mutant lung adenocarcinoma patients.
Small-scale displacement fluctuations of vesicles in fibroblasts
Authors: Posey Danielle , Blaisdell-Pijuan Paris , Knoll Samantha K. , Saif Taher A. , Ahmed Wylie W.
Published: August 2018

The intracellular environment is a dynamic space filled with various organelles moving in all directions. Included in this diverse group of organelles are vesicles, which are involved in transport of molecular cargo throughout the cell. Vesicles move in either a directed or non-directed fashion, often depending on interactions with cytoskeletal proteins such as microtubules, actin filaments, and molecular motors. How these proteins affect the local fluctuations of vesicles in the cytoplasm is not clear since they have the potential to both facilitate and impede movement. Here we show that vesicle mobility is significantly affected by myosin-II, even though it is not a cargo transport motor. We find that myosin-II activity increases the effective diffusivity of vesicles and its inhibition facilitates longer states of non-directed motion. Our study suggests that altering myosin-II activity in the cytoplasm of cells can modulate the mobility of vesicles, providing a possible mechanism for cells to dynamically tune the cytoplasmic environment in space and time.
Interplay between interferon regulatory factor 1 and BRD4 in the regulation of PD-L1 in pancreatic stellate cells
Authors: Ebine Kazumi , Kumar Krishan , Pham Thao N. , Shields Mario A. , Collier Katharine A. , Shang Meng , DeCant Brian T. , Urrutia Raul , Hwang Rosa F. , Grimaldo Sam , Principe Daniel R. , Grippo Paul J. , Bentrem David J. , Munshi Hidayatullah G.
Published: August 2018

The fibrotic reaction is a characteristic feature of human pancreatic ductal adenocarcinoma (PDAC) tumors. It is associated with activation and proliferation of pancreatic stellate cells (PSCs), which are key regulators of fibrosis in vivo. While there is increasing interest in the regulation of PD-L1 expression in cancer and immune cells, the expression and regulation of PD-L1 in other stromal cells, such as PSCs, has not been fully evaluated. Here we show that PSCs in vitro express higher PD-L1 mRNA and protein levels compared to the levels present in PDAC cells. We show that inhibitors targeting bromodomain and extra-terminal (BET) proteins and BRD4 knockdown decrease interferon-γ (IFN-γ)-induced PD-L1 expression in PSCs. We also show that c-MYC, one of the well-established targets of BET inhibitors, does not mediate IFN-γ-regulated PD-L1 expression in PSCs. Instead we show that interferon regulatory factor 1 (IRF1) mediates IFN-γ-induced PD-L1 expression in PSCs. Finally, while we show that BET inhibitors do not regulate IFN-γ-induced IRF1 expression in PSCs, BET inhibitors decrease binding of IRF1 and BRD4 to the PD-L1 promoter. Together, these results demonstrate the interplay between IRF1 and BRD4 in the regulation of PD-L1 in PSCs.
Barley RNA viromes in six different geographical regions in Korea
Authors: Jo Yeonhwa , Bae Ju-Young , Kim Sang-Min , Choi Hoseong , Lee Bong Choon , Cho Won Kyong
Published: August 2018

Barley is a kind of cereal grass belonging to the family Poaceae. To examine viruses infecting winter barley in Korea, we carried out a comprehensive study of barley RNA viromes using next-generation sequencing (NGS). A total of 110 barley leaf samples from 17 geographical locations were collected. NGS followed by extensive bioinformatics analyses revealed six different barley viromes: Barley yellow mosaic virus (BaYMV), Barley mild mosaic virus (BaMMV), Barley yellow dwarf virus (BYDV), Hordeum vulgare endornavirus (HvEV), and Barley virus G (BVG). BaYMV and HvEV were identified in all libraries, while other viruses were identified in some specific library. Based on the number of virus-associated reads, BaYMV was a dominant virus infecting winter barley in Korea causing yellow disease symptoms. We obtained nearly complete genomes of six BaYMV isolates and two BaMMV isolates. Phylogenetic analyses indicate that BaYMV and BaMMV were largely grouped based on geographical regions such as Asia and Europe. Single nucleotide polymorphisms analyses suggested that most BaYMV and BaMMV showed strong genetic variations; however, BaYMV isolate Jeonju and BaMMV isolate Gunsan exhibited a few and no SNPs, respectively, suggesting low level of genetic variation. Taken together, this is the first study of barley RNA viromes in Korea.
Bright GFP with subnanosecond fluorescence lifetime
Authors: Mamontova Anastasia V. , Solovyev Ilya D. , Savitsky Alexander P. , Shakhov Alexander М. , Lukyanov Konstantin A. , Bogdanov Alexey M.
Published: August 2018

Fluorescence lifetime imaging microscopy (FLIM) measures fluorescence decay rate at every pixel of an image. FLIM can separate probes of the same color but different fluorescence lifetimes (FL), thus it is a promising approach for multiparameter imaging. However, available GFP-like fluorescent proteins (FP) possess a narrow range of FLs (commonly, 2.3–3.5 ns) which limits their applicability for multiparameter FLIM. Here we report a new FP probe showing both subnanosecond fluorescence lifetime and exceptional fluorescence brightness (80% of EGFP). To design this probe we applied semi-rational amino acid substitutions selection. Critical positions (Thr65, Tyr145, Phe165) were altered based on previously reported effect on FL or excited state electron transfer. The resulting EGFP triple mutant, BrUSLEE (Bright Ultimately Short Lifetime Enhanced Emitter), allows for both reliable detection of the probe and recording FL signal clearly distinguishable from that of the spectrally similar commonly used GFPs. We demonstrated high performance of this probe in multiparameter FLIM experiment. We suggest that amino acid substitutions described here lead to a significant shift in radiative and non-radiative excited state processes equilibrium.
Organic amines as templates: pore imprints with exactly matching sizes in a series of metal–organic frameworks
Authors: Zhao Nian , Yang Lun , Xie Bo , Han Juanjuan , Pan Qiyun , Li Xiang , Liu Meifeng , Wang Yu , Wang Xiuzhang , Zhu Guangshan
Published: August 2018

Three metal–organic frameworks have been synthesized with an amine template strategy whose pore sizes exactly matched those of templates.
Increasing time on target: utilization of inhibitors of cysteine cathepsins to enhance the tumor retention of receptor-targeted agents
Authors: Fan Wei , Zhang Wenting , Alshehri Sameer , Garrison Jered C.
Published: August 2018

An efficient strategy of utilizing cysteine cathepsin inhibitor for enhanced tumor residence of the receptor-targeted agents was presented.
A halogen bond-donor amino acid for organocatalysis in water
Authors: Bergamaschi Greta , Lascialfari Luisa , Pizzi Andrea , Martinez Espinoza Maria Isabel , Demitri Nicola , Milani Alberto , Gori Alessandro , Metrangolo Pierangelo
Published: August 2018

An XB-donor amino acid compound F(F4I) effectively promotes homogeneous catalysis of condensation reactions in water.
Heteroepitaxial growth of single-phase ε-Ga2O3 thin films on c-plane sapphire by mist chemical vapor deposition using a NiO buffer layer
Authors: Arata Y. , Nishinaka H. , Tahara D. , Yoshimoto M.
Published: August 2018

In this study, single-phase ε-gallium oxide (Ga2O3) thin films were heteroepitaxially grown on c-plane sapphire substrates.
Strong electron–phonon interaction retarding phonon transport in superconducting hydrogen sulfide at high pressures
Authors: Yang Jia-Yue , Hu Ming
Published: August 2018

Ultrahigh pressure greatly shortens interatomic distances and induces strong electron–phonon coupling that significantly reduces the phonon transport of superconducting H3S.
Kinetics of the defunctionalization of oxidized few-layer graphene nanoflakes
Authors: Chernyak Sergei A. , Ivanov Anton S. , Podgornova Angelina M. , Arkhipova Ekaterina A. , Kupreenko Stepan Yu. , Shumyantsev Alexei V. , Strokova Natalia E. , Maslakov Konstantin I. , Savilov Serguei V. , Lunin Valery V.
Published: August 2018

Thermal defunctionalization of oxidized jellyfish-like few-layer graphene nanoflakes was studied.
Fabrication of magnetic g-C3N4 for effectively enhanced tetracycline degradation with RGO as mediator
Authors: Fan Wenqian , Zhu Zhi , Yu Yang , Liu Zhi , Li Chunxiang , Huo Pengwei , Qiu Yue , Yan Yongsheng
Published: August 2018

In the present work, the ternary hybrid photocatalyst Fe3O4@g-C3N4/RGO is developed by a facile hydrothermal method, which shows a satisfactory degradation rate (90%) and stability in degrading tetracycline.
Synthesis of disaccharide nucleoside analogues as potential poly(ADP-ribose) polymerase-1 inhibitors
Authors: Zheng Meng , Mex Martin , Götz Kathrin H. , Marx Andreas
Published: August 2018

The synthesis of novel disaccharide nucleoside analogues that resemble the central motif of poly(ADP-ribose) was developed and it was found that some of them show inhibitory effects on human poly(ADP-ribose) polymerase-1.
Effects of parathyroid hormone (1-34) on the regulation of the lysyl oxidase family in ovariectomized mice
Authors: Cai Linyi , Zhang Demao , Liu Wenjing , Cui Yujia , Jing Junjun , Xie Jing , Zhou Xuedong
Published: August 2018

LOX family is a potential target in ovariectomized osteoporosis (OP).
Preparation of Ru(ii)@oligonucleotide nanosized polymers as potential tumor-imaging luminescent probes
Authors: Yu Geng-Nan , Huang Jun-Chao , Li Li , Liu Ruo-Tong , Cao Jie-Qiong , Wu Qiong , Zhang Shuang-Yan , Wang Cheng-Xi , Mei Wen-Jie , Zheng Wen-Jie
Published: August 2018

Ru(ii)@oligonucleotide nanoparticles can be developed as potential tumor selective tracker and have potential applications of tumor targeting imaging.
Aldol condensation of refluxing acetone on CaC2 achieves efficient coproduction of diacetone alcohol, mesityl oxide and isophorone
Authors: Xu Xuebing , Meng Hong , Lu Yingzhou , Li Chunxi
Published: August 2018

The refluxing reaction of acetone on CaC2 realizes an efficient coproduction of diacetone alcohol, mesityl oxide, isophorone and C2H2.
Ultrathin Cu-MOF@δ-MnO2 nanosheets for aqueous electrolyte-based high-voltage electrochemical capacitors
Authors: Xu Jing , Wang Yan , Cao Shuai , Zhang Jian , Zhang Guangxun , Xue Huaiguo , Xu Qiang , Pang Huan
Published: August 2018

Ultrathin Cu-MOF@δ-MnO2 nanosheets have been successfully prepared and the operating voltage window of the asymmetric supercapacitor can reach high values in aqueous electrolyte without any water electrolysis.
All-carbon lithium capacitor based on salt crystal-templated, N-doped porous carbon electrodes with superior energy storage
Authors: Cui Yongpeng , Liu Wei , Lyu Yan , Zhang Yuan , Wang Huanlei , Liu Yujing , Li Dong
Published: August 2018

All-carbon LIC with higher energy density and lower cost are constructed based on NaHCO3 crystal designed N-doped carbon network.
Establishing new scaling relations on two-dimensional MXenes for CO2 electroreduction
Authors: Handoko Albertus D. , Khoo Khoong Hong , Tan Teck Leong , Jin Hongmei , Seh Zhi Wei
Published: August 2018

With alternating binding of reaction intermediates, O-terminated MXenes display low theoretical overpotential for CO2 reduction reaction.
Phosphorus-doped onion-like carbon for CO2 electrochemical reduction: the decisive role of the bonding configuration of phosphorus
Authors: Liu TianFu , Ali Sajjad , Lian Zan , Si ChaoWei , Su Dang Sheng , Li Bo
Published: August 2018

Phosphorus-doped carbon shows superior performance for the CO2 electrochemical reduction reaction, revealing the crucial role of the phosphorus bonding configuration.
Enhanced CO2 photoreduction by a graphene–porphyrin metal–organic framework under visible light irradiation
Authors: Sadeghi Nasrin , Sharifnia Shahram , Do Trong-On
Published: August 2018

A photocatalyst consisting of a porphyrin-based metal–organic framework (Al/PMOF) and amine-functionalized graphene (NH2-rGO) has been designed to reduce CO2.
Alloyed multi-shell quantum dots with tunable dual emission
Authors: Zhang Wenda , Zhuang Weidong , Xing Xianran , Xu Bing , Wu Dan , Liu Haochen , Wang Kai , Liu Ronghui , Sun Xiao Wei
Published: August 2018

In this work, we synthesized ZnxCd1−xSe/ZnS/ZnyCd1−ySe/ZnS dual emission-alloyed QDs for the first time.
Incorporating a microcellular structure into PVDF/graphene–nanoplatelet composites to tune their electrical conductivity and electromagnetic interference shielding properties
Authors: Zhao Biao , Zhao Chongxiang , Hamidinejad Mahdi , Wang Chongda , Li Ruosong , Wang Sai , Yasamin Kazemi , Park Chul B.
Published: August 2018

The electrical conductivity and the EMI shielding properties could be effectively tuned by the foaming degree.
Mitochondrial toxicity induced by a thiourea gold(i) complex: mitochondrial permeability transition and respiratory deficit
Authors: Yu Bingqiong , Ma Long , Jin Jiancheng , Jiang Fenglei , Zhou Gangcheng , Yan Kun , Liu Yi
Published: August 2018

Gold(i) complexes have been widely used as antibacterial and antitumor agents for their excellent biological activities.
Exploring major signaling cascades in melanomagenesis: a rationale route for targetted skin cancer therapy
Authors: Dantonio Paola M. , Klein Marianne O. , Freire Maria Renata V.B. , Araujo Camila N. , Chiacetti Ana Carolina , Correa Ricardo G.
Published: August 2018

Although most melanoma cases may be treated by surgical intervention upon early diagnosis, a significant portion of patients can still be refractory, presenting low survival rates within 5 years after the discovery of the illness. As a hallmark, melanomas are highly prone to evolve into metastatic sites. Moreover, melanoma tumors are highly resistant to most available drug therapies and their incidence have increased over the years, therefore leading to public health concerns about the development of novel therapies. Therefore, researches are getting deeper in unveiling the mechanisms by which melanoma initiation can be triggered and sustained. In this context, important progress has been achieved regarding the roles and the impact of cellular signaling pathways in melanoma. This knowledge has provided tools for the development of therapies based on the intervention of signal(s) promoted by these cascades. In this review, we summarize the importance of major signaling pathways (mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K)-Akt, Wnt, nuclear factor κ-light-chain-enhancer of activated B cell (NF-κB), Janus kinase (JAK)-signal transducer and activator of transcription (STAT), transforming growth factor β (TGF-β) and Notch) in skin homeostasis and melanoma progression. Available and developing melanoma therapies interfering with these signaling cascades are further discussed.
Plasminogen-binding proteins as an evasion mechanism of the host’s innate immunity in infectious diseases
Authors: Ayón-Núñez Dolores A. , Fragoso Gladis , Bobes Raúl J. , Laclette Juan P.
Published: August 2018

Pathogens have developed particular strategies to infect and invade their hosts. Amongst these strategies’ figures the modulation of several components of the innate immune system participating in early host defenses, such as the coagulation and complement cascades, as well as the fibrinolytic system. The components of the coagulation cascade and the fibrinolytic system have been proposed to be interfered during host invasion and tissue migration of bacteria, fungi, protozoa, and more recently, helminths. One of the components that has been proposed to facilitate pathogen migration is plasminogen (Plg), a protein found in the host’s plasma, which is activated into plasmin (Plm), a serine protease that degrades fibrin networks and promotes degradation of extracellular matrix (ECM), aiding maintenance of homeostasis. However, pathogens possess Plg-binding proteins that can activate it, therefore taking advantage of the fibrin degradation to facilitate establishment in their hosts. Emergence of Plg-binding proteins appears to have occurred in diverse infectious agents along evolutionary history of host–pathogen relationships. The goal of the present review is to list, summarize, and analyze different examples of Plg-binding proteins used by infectious agents to invade and establish in their hosts. Emphasis was placed on mechanisms used by helminth parasites, particularly taeniid cestodes, where enolase has been identified as a major Plg-binding and activating protein. A new picture is starting to arise about how this glycolytic enzyme could acquire an entirely new role as modulator of the innate immune system in the context of the host–parasite relationship.
Negative Association of Hepatitis B Virus With Hearing Impairment
Authors: Azizul Islam SKM , Chung Jin Wook , Lee Young-Sil , Cho HoChan , Moon Seong-Su
Published: August 2018

Purpose

Hearing impairment is one of the most common chronic diseases causing deterioration of the quality of life in elderly individuals. Several viral infections have been suggested to cause hearing impairment. We investigated association of hepatitis B virus (HBV) infection with hearing impairment using a representative sample of the Korean population.

Method

Participants included 6,583 men and 8,702 women, who were ≥ 20 years of age from the Korea National Health and Nutritional Examination Surveys of the Korean population (2010–2012). Air-conduction pure-tone thresholds were measured in a soundproof booth using an automatic audiometer for each ear at 6 frequencies (500, 1000, 2000, 3000, 4000, and 6000 Hz). An audiometric test and a laboratory examination, including an HBV surface antigen (HBsAg) test, were performed.

Results

Subjects who are HBsAg positive had lower average of pure-tone thresholds and lower prevalence of hearing impairment at both low/mid and high frequency compared with those without. Adjusted means of hearing thresholds were also lower among subjects who are HBsAg positive compared with subjects who are HBsAg negative. After the adjustment for age and gender, the odds of high-frequency mild hearing impairment were lower for subjects with HBV infection. In the multiple logistic regression analyses adjusting for confounding variables, the significant negative association between HBV infection and high-frequency mild hearing impairment still remained.

Conclusions

Contrary to previous reports, subjects who are HBsAg positive had a lower prevalence of hearing impairment compared with subjects who are HBsAg negative. Further studies are warranted to investigate the underlying mechanism regarding their negative relationship.
Verbal Agreement Inflection in German Children With Down Syndrome
Authors: Penke Martina
Published: August 2018

Purpose

The study aims to explore whether finite verbal morphology is affected in children/adolescents with Down syndrome (DS), whether observed deficits in this domain are indicative of a delayed or deviant development, and whether they are due to phonetic/phonological problems or deficits in phonological short-term memory.

Method

An elicitation task on subject–verb agreement, a picture-naming task targeting stem-final consonants that also express verbal agreement, a nonword repetition task, and a test on grammar comprehension were conducted with 2 groups of monolingual German children: 32 children/adolescents with DS (chronological age
M
= 11;01 [years;months]) and a group of 16 typically developing children (chronological age
M
= 4;00) matched on nonverbal mental age.

Results

Analyses reveal that a substantial number of children/adolescents with DS are impaired in marking verbal agreement and fail to reach an acquisition criterion. The production of word-final consonants succeeds, however, when these consonants do not express verbal agreement. Performance with verbal agreement and nonword repetition are related.

Conclusions

Data indicate that a substantial number of children/adolescents with DS display a deficit in verbal agreement inflection that cannot be attributed to phonetic/phonological problems. The influence of phonological short-term memory on the acquisition of subject–verb agreement has to be further explored.
Stochastic integration of demand response and reconfiguration in distribution network expansion planning
Authors: Gouin Victor , Alvarez Herault Marie‐Cecile , Raison Bertrand
Published: August 2018

Planning the distribution network of the future involves forecasting the most likely scenario to make appropriate investment decisions. Many uncertainties concerning, e.g. the evolution of conventional loads, renewable production and electric vehicles (EVs) make it difficult to predict the location of the distribution network's weaknesses (overvoltages, undervoltages and overcurrents) and their occurrence. In some cases, alternative solutions such as demand response (DR) and reconfiguration can remove the constraints and prevent expensive network investment. This study proposes a two‐stage algorithm that is able to give the probability that no technical constraints will appear as a function of the reinforcement cost with and without using DR and/or reconfiguration. The first stage of the algorithm consists in running Monte Carlo simulations based on realistic scenarios for loads, EVs and renewable production development provided by French governmental roadmaps. The cost of reinforcement per line and per hour of constraints enables selection of the feeders, where DR (solved with linear programming) and/or reconfiguration (exhaustive research) will be implemented in the second stage of the algorithm to remove these constraints. The methodology is applied to a real part of a French distribution network.
60 GHz wideband LTCC microstrip patch antenna array with parasitic surrounding stacked patches
Authors: Lee Hua‐Juan , Li Eric S. , Jin Huayan , Li Chung‐Yi , Chin Kuo‐Sheng
Published: August 2018

This work presents a wideband 60 GHz microstrip patch antenna (MPA) array based on low‐temperature co‐fired ceramic (LTCC) multilayer technology. Four parasitic patches are stacked above the driven MPA. An additional resonant mode is excited by the proposed parasitic surrounding stacked patches (PSSPs) to enhance the bandwidth of the MPA. The structure of the PSSPs increases the gain of the MPA due to its array configuration. The proposed PSSP structure can find many applications in designs for large‐scale antenna arrays because the PSSPs and the driven microstrip patch are distributed at different layers. This arrangement allows a direct feed network to the MPA without the blockage caused by the PSSPs. A 2 × 2 antenna array was designed and fabricated with the PSSPs to further increase its gain. The proposed array can achieve a gain of 10.5 dBi and a wide bandwidth of 27.3% at 60 GHz.
Coupled‐line trans‐directional coupler with arbitrary power divisions for equal complex termination impedances
Authors: Liu Hongmei , Xun Chenhui , Fang Shaojun , Wang Zhongbao , Liu Dong
Published: August 2018

In the study, a coupled line trans‐directional (CL‐TRD) coupler that allows for equal complex termination impedances with arbitrary power divisions is presented. It is composed of two pairs of coupled lines with an overall electrical length of 90°, two types of shunt capacitors and three pairs of short‐circuited stubs. By adjusting the electrical length of each short‐circuited stub, as well as the values of the shunt capacitors, arbitrary equal complex termination impedances and power divisions are achieved. Moreover, since capacitors are shunted between the coupled lines, the proposed CL‐TRD coupler has an inherent feature of dc blocking. Design equations for the CL‐TRD were derived using even–odd mode decomposition analysis. To validate the theory, several numerical examples extracted from the design procedure were listed. Eventually, two prototypes of the proposed CL‐TRD coupler are fabricated, and experiments are carried out. The measured results indicate that the coupler is able to realise arbitrary power divisions for equal complex termination impedance with good matching and isolation.
Advance system and model to predict malicious files prorogation inside computer network
Authors: Ahmad Ashraf , Abu Hour Yousef S. , DarAssi Mahmoud H.
Published: August 2018

A new model for malicious file propagation and transmission in a computer network is formulated. This model introduced a cure rate (E ‐cure rate) which is calculated after the regular running of anti‐virus in the systems of the computer network. This will result in monitoring the anti‐virus efficiency in fighting not only a local malicious file but also the global spreading of such a file. The file has to go through different scenarios including many other states. Therefore, a vertical transmission concept is introduced in the proposed model. The threshold conditions for the stability of the proposed model are determined. Numerous methods are used to prove that the viral equilibrium points of our model are globally and locally stable. The behaviour of the compartment nodes in the computer network has been analysed. In addition, the optimal control theory is used to study immunisation strategies against Malware in order to control the economic losses of security investments and keep infection loss at the lowest possible level. The existence and uniqueness of results related to the system are confirmed. Finally, the simulation shows that the spread of malware can be effectively controlled by choosing the appropriate control strategy of specific parameters.
MRT der Sakroiliakalgelenke: häufige Fehldiagnosen
Authors: Hermann Kay-Geert
Published: August 2018

Die axiale Spondyloarthritis ist die häufigste entzündlich-rheumatische Erkrankung des Achsenskeletts. Durch eine frühe Diagnosestellung – mit der MRT der Sakroiliakalgelenke – können ihre Spätschäden vermieden werden. Mit dem Ziel einer hohen Sensitivität werden dabei allerdings auch nicht-entzündliche Differenzialdiagnosen oder anatomische Varianten erfasst. Im Folgenden werden mögliche Fallstricke der MRT der Sakroiliakalgelenke dargestellt.
„Ich schau Dir in die Augen, Kleines“ – neuroradiologische Befunde bei okulomotorischen Störungen
Authors: Weidauer Stefan
Published: August 2018

Okulomotorische Störungen können durch pathologische intraorbitale Prozesse entstehen, aber auch, wenn das ZNS oder einzelne oder mehrere Hirnnerven betroffen sind. Insbesondere bei akutem Beginn können sie die Ouvertüre einer schweren neurologischen Erkrankung sein. In dieser Übersicht werden wichtige typische Befundkonstellationen unter Berücksichtigung anatomischer Kompartimente dargestellt.
Aldosterone to Renin Ratio as Screening Tool in Primary Aldosteronism
Authors: Schilbach Katharina , Junnila Riia , Bidlingmaier Martin
Published: August 2018

Primary aldosteronism (PA) is a severe and often underdiagnosed form of secondary hypertension. Determining the aldosterone to renin ratio (ARR) in hypertensive patients has been shown to be a valuable screening test for identification of patients suffering from PA. Since the introduction of a more widespread ARR screening the number of PA patients significantly increased worldwide. Interpretation of ARR might be challenging: Several factors from posture to interfering drugs affect the ARR and need to be taken into account when collecting samples. In addition, the wide variety of available assay methods and lack of well-established cut-offs present a challenge to the clinician. This review discusses the usefulness and possible difficulties of ARR screening.
K2S2O8-Mediated Arylmethylation of Indoles with Tertiary Amines via sp3 C–H Oxidation in Water
Authors: Yadav Lal , Singh Rana , Singh Manjula , Yadav Arvind
Published: August 2018

A transition-metal- and catalyst-free, highly efficient synthesis of 3-arylmethylindoles has been achieved using tertiary amines as both methylene (-CH2-) transfer and arylmethylation agents and K2S2O8 as a convenient oxidant. The key feature of this protocol is the utilisation of K2S2O8 as an inexpensive and easy to handle radical surrogate that can effectively promote the reaction, leading to the formation of C(sp2)–C(sp3)–C(sp2) bonds via sp3 C–H bond oxidation in water at room temperature in a one-pot procedure.
First measurements of remaining shell areal density on the OMEGA laser using the Diagnostic for Areal Density (DAD)
Authors: Rubery M. S. , Horsfield C. J. , Gales S. G. , Garbett W. J. , Leatherland A. , Young C. , Herrmann H. , Kim Y. , Hoffman N. M. , Mack J. M. , Aragonez R. , Sedillo T. , Evans S. , Brannon R. B. , Stoeckl C. , Ulreich J. , Sorce A. , Gates G. , Shoup M. J. , Peck B. , Gatu Johnson M. , Frenje J. A. , Milnes J. S. , Stoeffl W.
Published: August 2018

A glass Cherenkov detector, called the Diagnostic for Areal Density (DAD), has been built and implemented at the OMEGA laser facility for measuring fusion gammas above 430 keV, from which remaining shell ⟨ρR⟩abl can be determined. A proof-of-principle experiment is discussed, where signals from a surrogate gas Cherenkov detector are compared with reported values from the wedge range filter and charged particle spectrometer and found to correlate strongly. The design of the more compact port–based DAD diagnostic and results from the commissioning shots are then presented. Once absolutely calibrated, the DAD will be capable of reporting remaining shell ⟨ρR⟩abl for plastic and glass capsules within minutes of a shot and with potentially higher precision than existing techniques.
Social semantic networks: Measuring topic management in discourse using a pyramid of conceptual recurrence metrics
Authors: Angus Daniel , Wiles Janet
Published: August 2018

Studies of conversational encounters typically employ manual discourse analysis methods to reveal participants' topic management patterns, usually focusing on turn-by-turn interactions within a specific social context. These analyses, while powerful, are time-consuming to apply and can prove difficult to generalize. Recurrence analysis has recently been applied to discourse datasets to model how individual terms and concepts recur over whole conversation time scales and relate patterns of recurrence to topic management practices by individuals. In this paper, we propose a new multi-level quantitative method for modelling the topical interaction dynamics in conversation based on conceptual recurrence quantification analysis. The new protocol develops a hierarchy of speakers and their interactions, and partitions recurrence based on these groups. The new protocol is evaluated against expert human coding of television broadcast interviews. Our analysis reveals topic use patterns and networks of conceptual engagement (person-person and group-group) that show experts preferentially engaging with other experts rather than with laypeople, findings that are consistent with prior expectations for this discourse, although never before expressed as metrics. The studies provide a starting point for new computational protocols to provide fast, semi-automated methods for measuring the degree of conceptual interaction between individuals and groups.
Hydrogen motional disorder in crystalline iron group chloride dihydrates
Authors: Walder Brennan J. , Patterson Alex M. , Baltisberger Jay H. , Grandinetti Philip J.
Published: August 2018

The principal components and the relative orientation of the 2H paramagnetic shift and quadrupolar coupling tensors have been measured for the MCl2·2D2O family of compounds, M = Mn, Fe, Co, Ni, and Cu, using the two-dimensional shifting-d echo nuclear magnetic resonance experiment in order to determine (1) the degree of unpaired electron delocalization and (2) the number and location of crystallographically distinct hydrogen sites around oxygen and their fractional occupancies. Expressions for the molecular susceptibility of 3d ion systems, where the spin-orbit coupling is a weak perturbation onto the crystal field, are derived using the generalized Van Vleck equation and used to predict molecular susceptibilities. These predicted molecular susceptibilities are combined with various point dipole source configurations modeling unpaired electron delocalization to predict 2H paramagnetic shift tensors at potential deuterium sites. The instantaneous deuterium quadrupolar coupling and shift tensors are then combined with parameterized motional models, developed for trigonally (M = Mn, Fe, Co, and Cu) and pyramidally (M = Ni) coordinated D2O ligands, to obtain the best fit of the experimental 2D spectra. Dipole sources placed onto metal nuclei with a small degree of delocalization onto the chlorine ligands yield good agreement with the experiment for M = Mn, Fe, Co, and Ni, while good agreement for CuCl2·2D2O is obtained with additional delocalization onto the oxygen. Our analysis of the salts with trigonally coordinated water ligands (M = Mn, Fe, Co, and Cu) confirms the presence of bisector flipping and the conclusions from neutron scattering measurements that hydrogen bonding to chlorine on two adjacent chains leads to the water molecule in the [M(D2O)2Cl4] cluster being nearly coplanar with O–M–Cl involving the shortest metal-chlorine bonds of the cluster. In the case of NiCl2·2D2O, the experimental parameters were found to be consistent with a motional model where the D2O ligands are pyramidally coordinated to the metal and undergo bisector flipping while the water ligand additionally hops between two orientations related by a 120° rotation about the Ni–O bond axis. The position of the three crystallographically distinct hydrogen sites in the unit cell was determined along with fractional occupancies. This restricted water ligand motion is likely due to van der Waals interactions and is concerted with the motion of neighboring ligands.
Demonstration of multi-hit and multi-mass capability of 3D imaging in a conventional velocity map imaging experiment
Authors: Weeraratna Chaya , Amarasinghe Chandika , Lee Suk Kyoung , Li Wen , Suits Arthur G.
Published: August 2018

Coincidence and three-dimensional (3D) imaging offer unique capability in photodissociation and scattering experiments, and a variety of methods have been developed. The basic concept behind all these approaches is to register both the position (x, y) at which the particle hits the detector and the arrival time (t). A novel advance to the time and position sensitive detection was introduced recently by Li and co-workers [Rev. Sci. Instrum. 85(12), 123303 (2014)]. This method utilizes a high-speed digitizer and a computer algorithm along with the camera and detector usually employed in a conventional velocity map imaging apparatus. Due to the normal intensity variations of the ion spots, a correlation can be made between ion intensity recorded by the camera and peak intensity in the digitizer. This makes it possible to associate each ion spot’s position with its respective arrival time, thereby constructing a 3D distribution. The technique was primarily introduced for ultrafast ion and electron imaging experiments at high repetition rate with single or few events per image frame. We have recently succeeded in adapting this approach at low repetition rate. Modifications were done to the initial setup to enhance the acquisition efficiency to obtain and correlate multiple hits per laser shot rather than single-hit events. The results are demonstrated in two experiments, dimethyl amine dissociative ionization at 205 nm and carbonyl sulfide photodissociation at 217 nm, with up to 27 events correlated in a single frame. Temporal and spatial slicing capabilities were achieved with good resolution, giving the photofragment velocity and angular distribution for multiple masses simultaneously.
A new method for producing uniform droplets by continuous-ink-jet technology
Authors: Wang Tongju , Lin Jian , Guo Xingye , Lei Yongping , Fu Hanguang
Published: August 2018

Droplets produced by continuous-ink-jet printing are widely used in various fields. The gas pressure in the feedstock tank and the perturbation imposed on a capillary jet are the primary parameters to control the formation process of the droplets. However, the lack of a simple method for producing perturbation is a major limitation of continuous-ink-jet technology. Therefore, based on the technology of electromagnetic force perturbation, a novel and simple system to produce the desired perturbation frequency is constructed in this article. Experiments were conducted with distilled water. The droplet formation process experiences three modes with the increase of the disturbance frequency. The uniform droplets could be produced in a certain region when the gas pressure in the feedstock tank is constant, and the variation of the jet tip had an important influence on the uniform droplet formation. The size of droplets could be changed by the control of the disturbance frequency.
Fully developed building unit cavity source for long multiple shallow cavity configurations
Authors: Shaaban Ayman A. , Ziada Samir
Published: August 2018

Fluid resonant oscillations have been reported for corrugated pipes installed in offshore gas and oil fields. Corrugated pipes can be modelled as a series of consecutive shallow cavities. The current study investigates the development of the individual cavity source along multiple-cavity arrangements and whether this source eventually reaches a fully developed form with a persistent source contribution. Such a contribution defines a proposed building unit cavity source. To achieve this objective, the aeroacoustic source of a test section with a gradually increasing number of cavities is measured by means of the standing wave method. The individual cavity source is found to asymptotically reach a constant value starting from the fourth cavity. This source value is a function of the excitation level and eventually decays at a high excitation level of 10%. The measured building unit source is validated by two different approaches. First, a prediction model is developed for a twelve-cavity configuration based on the building unit source. Fair agreement is found between the predicted and the experimentally measured pressure amplitudes. The second validation approach involves extracting the source of the ninth cavity in a twelve-cavity configuration using Howe’s analogy based on particle image velocimetry measurements. The ninth cavity source fairly matches the building unit source for excitation levels higher than 1%. For lower excitation levels, three-dimensional flow effects are found to become more dominant and lead to larger discrepancies with the unit source.
Elastic shear modulus constitutive law found from entropy considerations
Authors: Burns S. J.
Published: August 2018

Isothermal and adiabatic shear moduli have been measured countless times. Adiabatic shear moduli which are generally considered to be the same as isothermal shear moduli are shown here to be unstable, so they cannot exist. A constitutive law that avoids adiabatic moduli is found to apply to polycrystalline isotropic solids. The equation is a power law in the volume per unit mass time the shear modulus. The volume is in turn a function of temperature T and pressure p in the system. The adiabatic moduli are established in shear stress versus strain space using a construction from isothermal elastic shear moduli. The derivation of this law replaces adiabatic with isochoric conditions in linear elastic, sheared solids. It is widely reported that the shear thermal expansion coefficient is zero since isotropic solids do not change the shape when heated. All solids with applied shear stresses and temperature dependent shear moduli change the shape and have shear thermal expansion coefficients. The thermal expansion coefficient is coupled into the shear component of the entropy and the T dependence of the isothermal shear modulus. In a sheared solid, only the single point τ = 0, γ = 0 has no shear entropy contributions and no thermal expansion and is mechanically unstable in adiabatic constructions. The exact form of the proposed constitutive law is based on solutions from a second order differential equation based on shear contributions from the entropy.
Effect of uneven wall blowing on hypersonic boundary-layer stability and transition
Authors: Miró Miró Fernando , Pinna Fabio
Published: August 2018

The understanding of aerothermodynamics in complex multiphysics environments such as atmospheric entry is of vital importance for the design of optimized vehicles. A better insight into the interaction between the thermal protection system ablation and the flow’s stability and transition would significantly increase the available payload and reduce the overall mission costs. In order to improve the modeling of the effect of ablation-induced outgassing, a continuously blowing boundary condition for linear stability theory is developed and tested against existing homogeneous and porous conditions in cold wind-tunnel calorically perfect gas conditions. The new model predicts a substantially higher destabilization of the boundary layer than the classic one. An exhaustive parametric study addresses the effect of the most important parameters influencing the boundary condition characteristics. Porous layer stabilization/destabilization maps for different porous layers and flow conditions are built, serving as a starting point for a stabilizing-porous-coating design methodology. Previous controversial literature findings are clarified in the light of the current work, showing a consistent way of addressing similar future tests. The semiempirical eN method is used to predict the location of transition onset in noisy wind-tunnel conditions, obtaining substantially different predictions with different wall models.
Heteronuclear molecules from matrix isolation sublimation and atomic diffusion
Authors: Oliveira A. N. , Sacramento R. L. , Moreira L. S. , Azevedo L. O. A. , Wolff W. , Lenz Cesar C.
Published: August 2018

We demonstrate the production of cryogenic beams of heteronuclear molecules from the matrix isolation sublimation (MISu) technique. A sapphire mirror serves as a substrate whereupon a solid Ne matrix is grown. Atoms of Li, H, Ca, and C are implanted into the matrix via subsequent laser ablation of different solid precursors such as Ca, Li, LiH, and graphite. The matrix is sublimated into vacuum generating a cryogenic beam of Ne carrying the previously isolated neutral atomic and molecular species. A compact and low energy electron source and time-of-flight mass spectrometer was designed to fit this system at low temperature. With electron ionization time-of-flight mass spectrometry, we analyze the species coming from MISu and demonstrate the formation of heteronuclear molecules in the matrix. In this first study, we produced LiCa from the sequential implantation of Li and Ca into the matrix and some clusters of CnLim after Li and C ablation. Also from ablation of a single LiH pellet, we observed clusters of LinHm. This novel technique opens up the opportunity to generate cryogenic beams of different molecules for precision physics and chemistry studies. Laser or microwave high resolution spectroscopy of a molecular beam benefits from low translational and rovibrational temperatures and forward velocities, such as the ones produced in this technique. Toward the prospect of enhancing the molecular formation, we introduce a new method to study the atomic diffusion of Li and Ca in the Ne matrix via laser spectroscopy during sublimation. We estimate a small diffusion coefficient at 7 K, but a surprisingly linear atomic dispersion during sublimation. The method is extensive to other species and matrices.
Harmonic surface mapping algorithm for fast electrostatic sums
Authors: Zhao Qiyuan , Liang Jiuyang , Xu Zhenli
Published: August 2018

We propose a harmonic surface mapping algorithm (HSMA) for electrostatic pairwise sums of an infinite number of image charges. The images are induced by point sources within a box due to a specific boundary condition which can be non-periodic. The HSMA first introduces an auxiliary surface such that the contribution of images outside the surface can be approximated by the least-squares method using spherical harmonics as basis functions. The so-called harmonic surface mapping is the procedure to transform the approximate solution into a surface charge and a surface dipole over the auxiliary surface, which becomes point images by using numerical integration. The mapping procedure is independent of the number of the sources and is considered to have a low complexity. The electrostatic interactions are then among those charges within the surface and at the integration points, which are all the forms of Coulomb potential and can be accelerated straightforwardly by the fast multipole method to achieve linear scaling. Numerical calculations of the Madelung constant of a crystalline lattice, electrostatic energy of ions in a metallic cavity, and the time performance for large-scale systems show that the HSMA is accurate and fast, and thus is attractive for many applications.