bluuebunny/crossref_metadata_2025 huggingface dataset:
Seismo‐Mechanical Response of Anisotropic Rocks Under Hydraulic Fracture Conditions: New Experimental Insights
Authors: Gehne S. , Benson P. M. , Koor N. , Dobson K. J. , Enfield M. , Barber A.
Published: August 2019

Unconventional hydrocarbon resources found across the world are driving a renewed interest in mudrock hydraulic fracturing methods. However, given the difficulty in safely measuring the various controlling factors in a natural environment, considerable challenges remain in understanding the fracture process. To investigate, we report a new laboratory study that simulates hydraulic fracturing using a conventional triaxial apparatus. We show that fracture orientation is primarily controlled by external stress conditions and the inherent rock anisotropy and fabric are critical in governing fracture initiation, propagation, and geometry. We use anisotropic Nash Point Shale (NPS) from the early Jurassic with high elastic P wave anisotropy (56%) and mechanical tensile anisotropy (60%), and highly anisotropic (cemented) Crab Orchard Sandstone with P wave/tensile anisotropies of 12% and 14%, respectively. Initiation of tensile fracture requires 36 MPa for NPS at 1‐km simulated depth and 32 MPa for Crab Orchard Sandstone, in both cases with cross‐bedding favorable orientated. When unfavorably orientated, this increases to 58 MPa for NPS at 800‐m simulated depth, far higher as fractures must now traverse cross‐bedding. We record a swarm of acoustic emission activity, which exhibits spectral power peaks at 600 and 100 kHz suggesting primary fracture and fluid‐rock resonance, respectively. The onset of the acoustic emission data precedes the dynamic instability of the fracture by 0.02 s, which scales to ~20 s for ~100‐m size fractures. We conclude that a monitoring system could become not only a forecasting tool but also a means to control the fracking process to prevent avoidable seismic events.
Large‐Amplitude Mountain Waves in the Mesosphere Observed on 21 June 2014 During DEEPWAVE: 2. Nonlinear Dynamics, Wave Breaking, and Instabilities
Authors: Fritts David C. , Wang Ling , Taylor Michael J. , Pautet Pierre‐Dominique , Criddle Neal R. , Kaifler Bernd , Eckermann Stephen D. , Liley Ben
Published: August 2019

Weak cross‐mountain flow over the New Zealand South Island on 21 June 2014 during the Deep Propagating Gravity Wave Experiment (DEEPWAVE) led to large‐amplitude mountain waves in the mesosphere and lower thermosphere. The mesosphere and lower thermosphere responses were observed by ground‐based instruments in the lee of the Southern Alps supporting DEEPWAVE, including an Advanced Mesosphere Temperature Mapper, a Rayleigh lidar, an All‐Sky Imager, and a Fabry‐Perot Interferometer. The character of the mountain wave responses at horizontal scales of ~30–90 km reveals strong “sawtooth” variations in the temperature field suggesting large vertical and horizontal displacements leading to mountain wave overturning. The observations also reveal multiple examples of apparent instability structures within the mountain wave field that arose accompanying large amplitudes and exhibited various forms, scales, and evolutions. This paper employs detailed data analyses and results of numerical modeling of gravity wave instability dynamics to interpret these mountain wave dynamics, their instability forms, scales, and expected environmental influences. Results demonstrate apparently general instability pathways for breaking of large‐amplitude gravity waves in environments without and with mean shear. A close link is also found between large‐amplitude gravity waves and the dominant instability scales that may yield additional abilities to quantify gravity wave characteristics and effects.
Interface Flow With Vertically Varying Hydraulic Conductivity
Authors: Toller Erik A. L. , Strack Otto D. L.
Published: August 2019

We present an approach for solving problems of saltwater intrusion in aquifers with an hydraulic conductivity that varies in the vertical direction. The approach is based on the concept of a comprehensive potential, whose gradient exactly represents the vertically integrated discharge, which is, by definition, a two‐dimensional vector. We apply the approach to an island in Sweden and use it to estimate maximum allowable pumping rates of wells that recover part of the infiltration on the island.
Sex pilus specific bacteriophage to drive bacterial population towards antibiotic sensitivity
Authors: Colom Joan , Batista Diego , Baig Abiyad , Tang Ying , Liu Siyang , Yuan Fangzhong , Belkhiri Aouatif , Marcelino Lucas , Barbosa Fernanda , Rubio Marcela , Atterbury Robert , Berchieri Angelo , Barrow Paul
Published: August 2019

Antimicrobial resistance (AMR) is now a major global problem largely resulting from the overuse of antibiotics in humans and livestock. In some AMR bacteria, resistance is encoded by conjugative plasmids expressing sex-pili that can readily spread resistance through bacterial populations. The aim of this study was to use sex pilus-specific (SPS) phage to reduce the carriage of AMR plasmids. Here, we demonstrate that SPS phage can kill AMR Escherichia coli and select for AMR plasmid loss in vitro. For the first time, we also demonstrate that SPS phage can both prevent the spread of AMR Salmonella Enteritidis infection in chickens and shift the bacterial population towards antibiotic sensitivity.
Accurate Classification of Biological and non-Biological Interfaces in Protein Crystal Structures using Subtle Covariation Signals
Authors: Fukasawa Yoshinori , Tomii Kentaro
Published: August 2019

Proteins often work as oligomers or multimers in vivo. Therefore, elucidating their oligomeric or multimeric form (quaternary structure) is crucially important to ascertain their function. X-ray crystal structures of numerous proteins have been accumulated, providing information related to their biological units. Extracting information of biological units from protein crystal structures represents a meaningful task for modern biology. Nevertheless, although many methods have been proposed for identifying biological units appearing in protein crystal structures, it is difficult to distinguish biological protein–protein interfaces from crystallographic ones. Therefore, our simple but highly accurate classifier was developed to infer biological units in protein crystal structures using large amounts of protein sequence information and a modern contact prediction method to exploit covariation signals (CSs) in proteins. We demonstrate that our proposed method is promising even for weak signals of biological interfaces. We also discuss the relation between classification accuracy and conservation of biological units, and illustrate how the selection of sequences included in multiple sequence alignments as sources for obtaining CSs affects the results. With increased amounts of sequence data, the proposed method is expected to become increasingly useful.
Association of Aggresomes with Survival Outcomes in Pediatric Medulloblastoma
Authors: Yehia Maha , Taha Hala , Salama Asmaa , Amer Nada , Mosaab Amal , Hassanain Omneya , Refaat Amal , Yassin Dina , El-Hemaly Ahmed , Ahmed Soha , El-Beltagy Mohamed , Shaalan Osama , El-Naggar Shahenda
Published: August 2019

Aggresomes are inclusion bodies for misfolded/aggregated proteins. Despite the role of misfolded/aggregated proteins in neurological disorders, their role in cancer pathogenesis is poorly defined. In the current study we aimed to investigate whether aggresomes-positivity could be used to improve the disease subclassification and prognosis prediction of pediatric medulloblastoma. Ninety three pediatric medulloblastoma tumor samples were retrospectively stratified into three molecular subgroups; WNT, SHH and non-WNT/non-SHH, using immunohistochemistry and Multiplex Ligation Probe Amplification. Formation of aggresomes were detected using immunohistochemistry. Overall survival (OS) and event-free survival (EFS) were determined according to risk stratification criteria. Multivariate Cox regression analyses were carried out to exclude confounders. Aggresomes formation was detected in 63.4% (n = 59/93) of samples. Aggresomes were non-randomly distributed among different molecular subgroups (P = 0.00002). Multivariate Cox model identified aggresomes’ percentage at ≥20% to be significantly correlated with patient outcome in both OS (HR = 3.419; 95% CI, 1.30–8.93; P = 0.01) and EFS (HR = 3; 95% CI, 1.19–7.53; P = 0.02). The presence of aggresomes in ≥20% of the tumor identified poor responders in standard risk patients; OS (P = 0.02) and EFS (P = 0.06), and significantly correlated with poor outcome in non-WNT/non-SHH molecular subgroup; OS (P = 0.0002) and EFS (P = 0.0004).
The use of aggregation-induced emission probe doped silica nanoparticles for the immunoassay of human epididymis protein 4
Authors: Meng Lianjie , Nawaz Muhammad Azhar Hayat , Huang Xinan , Ma Yuqin , Li Yongxin , Zhou Huipeng , Yu Cong
Published: August 2019

A sensitive immunoassay for the sensing of human epididymis protein 4 is developed based on aggregation-induced emission probe doped silica nanoparticles.
Intermolecular coupling and intramolecular cyclization of aryl nitriles on Au(111)
Authors: Klaasen Henning , Liu Lacheng , Gao Hong-Ying , Viergutz Lena , Held Philipp A. , Knecht Tobias , Meng Xiangzhi , Börner Melanie C. , Barton Dennis , Amirjalayer Saeed , Neugebauer Johannes , Studer Armido , Fuchs Harald
Published: August 2019

The on-surface dimerization reaction of an organic nitrile on Au(111) is reported. The reaction cascade yielding a diazapyrene core was investigated by scanning tunneling microscopy, computational studies and reference compounds.
Electron bifurcation: progress and grand challenges
Authors: Yuly Jonathon L. , Lubner Carolyn E. , Zhang Peng , Beratan David N. , Peters John W.
Published: August 2019

Electron bifurcation moves electrons from a two-electron donor to reduce two spatially separated one-electron acceptors.
A stable iron-containing polyoxometalate coupled with semiconductor for efficient photocatalytic water oxidation under acidic condition
Authors: Hu Qiyu , Meng Xiangyu , Dong Yinjuan , Han Qing , Wang Yifan , Ding Yong
Published: August 2019

A homogeneous molecular catalyst, polyoxometalate (POM) Fe11, can act as a true cocatalyst for the efficient oxygen evolution reaction through the pH adjustment strategy when BiVO4 is used as a light-harvesting material.
Inorganic–organic hybrid high-dimensional polyoxotantalates and their structural transformations triggered by water
Authors: Li Zhong , Zhang Jing , Lin Li-Dan , Liu Jin-Hua , Li Xin-Xiong , Zheng Shou-Tian
Published: August 2019

In this work, novel dimeric polyoxotantalate (POTa) clusters {Cu(en)(Ta6O19)}2/{Cu(enMe)(Ta6O19)}2 were introduced as SBUs to construct a new family of extended POTa materials, including the first two 3D POTa frameworks and two 2D POTa layers.
Switching hydrogen bonds to readily interconvert two room-temperature long-term stable crystalline polymorphs in chiral molecular perovskites
Authors: Hu Wang-Hua , Xu Wei-Jian , Meng Qian-Ru , Zhang Xue-Wen , He Chun-Ting , Zhang Wei-Xiong , Chen Xiao-Ming
Published: August 2019

Two room-temperature polymorphic forms could be long-term stable yet easily interconvertible by switching the inter-cationic H-bonds in chiral molecular perovskites.
Reductively dissociable biomimetic nanoparticles for control of integrin-coupled inflammatory signaling to retard atherogenesis
Authors: Gao Wen , Yang Huazhen , Liu Xianghua , Liu Zhenhua , Tong Lili , Sun Yuhui , Cao Wenhua , Cao Yujie , Tang Bo
Published: August 2019

Reductively dissociable biomimetic nanoparticles EC-BSA-MnO2 were developed for the control of integrin-coupled inflammatory signaling to retard atherogenesis.
Micro-electro-flow reactor (μ-EFR) system for ultra-fast arene synthesis and manufacture of daclatasvir
Authors: Mahajan Bhushan , Mujawar Taufiqueahmed , Ghosh Subhash , Pabbaraja Srihari , Singh Ajay K.
Published: August 2019

Electro-micro flow reactor containing Pt@Ni@Cu anode materials for reductant free biaryl synthesis, further extended to daclatasvir synthesis.
Exploring chemical space in the search for improved azoheteroarene-based photoswitches
Authors: Vela Sergi , Krüger Constantin , Corminboeuf Clémence
Published: August 2019

A computational screening of azoheteroarenes identifies good candidates and provides guidelines on how to tune their performance through chemical substitution.
Hollow In2O3@ZnFe2O4 heterojunctions for highly efficient photocatalytic degradation of tetracycline under visible light
Authors: Fei Weihua , Song Yun , Li Najun , Chen Dongyun , Xu Qingfeng , Li Hua , He Jinghui , Lu Jianmei
Published: August 2019

In2O3@ZnFe2O4 hollow structure heterojunctions were synthesized by loading ZnFe2O4 nanosheets on the outer surface of hollow In2O3 and then employed for highly efficient photocatalytic degradation of tetracycline under visible light.
Enhanced adsorption of perfluoro alkyl substances for in situ remediation
Authors: Aly Yousof H. , McInnis Daniel P. , Lombardo Samuel M. , Arnold William A. , Pennell Kurt D. , Hatton James , Simcik Matt F.
Published: August 2019

Numerous groundwater sites around the globe have been contaminated by aqueous film forming foam (AFFF) as a result of firefighting, fire training activities and the storage and accidental spillage of AFFF.
Enzyme-catalysed enantioselective oxidation of alcohols by air exploiting fast electrochemical nicotinamide cycling in electrode nanopores
Authors: Wan Lei , Heath Rachel S. , Siritanaratkul Bhavin , Megarity Clare F. , Sills Adam J. , Thompson Matthew P. , Turner Nicholas J. , Armstrong Fraser A.
Published: August 2019

Enantioselective conversion of alcohols to ketones using air as the oxidant is achieved with high rates and efficiency using an indium tin oxide electrode in which an alcohol dehydrogenase and a NADPH recycling enzyme are confined within nanopores.
Highly transparent, healable, and durable anti-fogging coating by combining hydrophilic pectin and tannic acid with poly(ethylene terephthalate)
Authors: Zhang Tao , Fang Lanlan , Lin Nan , Wang Jiajun , Wang Yongguang , Wu Tao , Song Pingan
Published: August 2019

A highly transparent and healable anti-fogging coating was constructed via a facile dip-coating method from bio-derived pectin and tannic acid.
Microphysiological lung models to evaluate the safety of new pharmaceutical modalities: a biopharmaceutical perspective
Authors: Ainslie Garrett R. , Davis Myrtle , Ewart Lorna , Lieberman Linda A. , Rowlands David J. , Thorley Andrew J. , Yoder Gorm , Ryan Anne M.
Published: August 2019

Drug developers seek specific advancements in the development and qualification of microphysiological lung models for the evaluation of drug safety; here these essential elements are discussed from the perspective of the biopharmaceutical industry.
Cytotoxic activity of copper(ii), nickel(ii) and platinum(ii) thiosemicarbazone derivatives: interaction with DNA and the H2A histone peptide
Authors: Bisceglie Franco , Orsoni Nicolò , Pioli Marianna , Bonati Beatrice , Tarasconi Pieralberto , Rivetti Claudio , Amidani Davide , Montalbano Serena , Buschini Annamaria , Pelosi Giorgio
Published: August 2019

Metal complexes still represent promising pharmacological tools in the development of new anticancer drugs. Bis(citronellalthiosemicarbazonate)nickel(ii) is a metal compound extremely effective against leukemic and NCS cancer cell lines. Preliminary experiments performed with this compound and with its Cu(ii) and Pt(ii) analogues evidenced alterations, detectable by comet assay, in the DNA of treated U937 cells. In addition, [Cu(tcitr)2] and [Pt(tcitr)2] were also able to induce gene mutations and produce frameshift events. To gain further insights into the mechanism of action of these metal compounds, we carried out a multidisciplinary study to investigate whether their biological activity can be ascribed to the direct interaction with DNA or with chromatin. The DNA interaction was investigated by means of CD and UV-Vis spectroscopic techniques and by AFM, whereas the chromatin interaction was studied by analyzing the effects of the compounds on the structure of a peptide that mimicks the potential metal binding site in the “C-tail” region of histone H2A by means of NMR, CD, UV-Vis and MS. The intensities of the effects induced by the metal compounds on the peptide follow the order [Ni(tcitr)2] > [Pt(tcitr)2] ≫ [Cu(tcitr)2]. From the AFM data, a remarkable DNA compaction was observed in the presence of [Pt(tcitr)2], while [Ni(tcitr)2] causes the formation of large interlaced DNA aggregates.
Occurrence of excited state charge separation in a N-doped graphene–perylenediimide hybrid formed via ‘click’ chemistry
Authors: Gobeze Habtom B. , Arellano Luis M. , Gutiérrez-Vílchez Ana María , Gómez-Escalonilla María J. , Sastre-Santos Ángela , Fernández-Lázaro Fernando , Langa Fernando , D'Souza Francis
Published: August 2019

A donor–acceptor hybrid was devised and synthesized using N-doped graphene and perylene diimide via click chemistry, and the occurrence of excited state charge separation is demonstrated.
Medium-sized cyclic bis(anisylphosphonothioyl)disulfanes and their corresponding cyclic sulfane-structures and most characteristic reactions
Authors: Przychodzeń Witold , Chojnacki Jarosław , Nierzwicki Łukasz
Published: August 2019

A family of cyclic medium-sized disulfanes and related sulfanes was synthesized and characterized, followed by desulfurization and disulfane ammonolysis.
α-Halogenoacetamides: versatile and efficient tools for the synthesis of complex aza-heterocycles
Authors: El Bouakher Abderrahman , Martel Arnaud , Comesse Sébastien
Published: August 2019

This review presents the use of α-alkyl- and α-alkoxy-halogenoacetamides as powerful partners for domino and 1,3-dipolar cycloaddition reactions resulting in a ring closure.
Photosensitivity responses ofSagittula stellataprobed by FTIR, fluorescence and Raman microspectroscopy
Authors: Papageorgiou Marios , Tselios Charalampos , Varotsis Constantinos
Published: August 2019

Raman, fluorescence and FTIR experiments of prestineSagittula stellataandSagittula stellata–metal ion complexes grown in light and in dark were performed to probe the photosensitivity response of the cellular components in the marine bacterium.
Model Affitin and PEG modifications onto siRNA lipid nanocapsules: cell uptake and in vivo biodistribution improvements
Authors: Resnier Pauline , Lepeltier Elise , Emina Anthea Lucrezia , Galopin Natacha , Bejaud Jérôme , David Stephanie , Ballet Caroline , Benvegnu Thierry , Pecorari Frédéric , Chourpa Igor , Benoit Jean-Pierre , Passirani Catherine
Published: August 2019

Surface modifications of siRNA LNCs were assessed with innovative TE-PEG polymers and an Affitin model, in comparison to classic DSPE-PEG LNCs, in order to evaluate the potential tumor targeting of siRNA after intravenous administration.
Carbonisation temperature dependence of electrochemical activity of nitrogen-doped carbon fibres from electrospinning as air-cathodes for aqueous-alkaline metal–air batteries
Authors: Gehring Markus , Tempel Hermann , Merlen Alexandre , Schierholz Roland , Eichel Rüdiger-A. , Kungl Hans
Published: August 2019

Nitrogen-doped carbon fibres derived from electrospun poly-acrylonitrile display an optimum catalytic activity towards the oxygen reduction reaction in aqueous-alkaline metal–air batteries, when carbonised under argon at 850 °C.
The first demonstration of a novel isolated fungusEutypellasp. BJ associated with the biodegradation of polyvinyl alcohol
Authors: Deng Yiling , Wang Chenyuan , Liu Yalan , Chen Ping , Lin Xiaoshan , Zhang Yi
Published: August 2019

An isolated fungusEutypellasp. BJ is firstly demonstrated to have the ability to degrade polyvinyl alcohol.
Investigation on the quality diversity and quality-FTIR characteristic relationship of sunflower seed oils
Authors: Yi Yang , Yao Juan , Xu Wei , Wang Li-Mei , Wang Hong-Xun
Published: August 2019

For sunflower seed oils, FTIR combined with chemometrics was feasible for analyzing their quality diversity, cooking-caused changes and fatty acid compositions.
Catalyst-free hydrophosphination of alkenes in presence of 2-methyltetrahydrofuran: a green and easy access to a wide range of tertiary phosphines
Authors: Bissessar Damien , Egly Julien , Achard Thierry , Steffanut Pascal , Bellemin-Laponnaz Stéphane
Published: August 2019

A hydrophosphination reaction that is free of base, acid and catalyst, using only 2-methyltetrahydrofuran as additive has been performed.
Highly monodisperse zwitterion functionalized non-spherical polymer particles with tunable iridescence
Authors: Vasantha Vivek Arjunan , Rusli Wendy , Junhui Chen , Wenguang Zhao , Sreekanth Kandammathe Valiyaveedu , Singh Ranjan , Parthiban Anbanandam
Published: August 2019

A convenient method to fabricate functional photonic crystal arrays using self-assembled non-spherical particles that form tunable iridescent polymer opal by changing size and morphologies, thereby producing new responsive photonic material.
Electrical characterization of leaf-based wires & supercapacitors
Authors: Adhikari Ramesh Y. , Terrell Jack , Targos James , Huffman Kenneth A. , Wang Huihui , Cradlebaugh Joseph
Published: August 2019

Plant leaves were used to construct conducting channels and supercapacitors within.
Oxygen sensors for flow reactors – measuring dissolved oxygen in organic solvents
Authors: Sulzer Philipp , Lebl René , Kappe C. Oliver , Mayr Torsten
Published: August 2019

We are demonstrating a solvent resistant optical sensor for measuring dissolved oxygen in pressurized micro flow reactors.
Efficient in vivo synthesis of lasso peptide pseudomycoidin proceeds in the absence of both the leader and the leader peptidase
Authors: Zyubko Tatyana , Serebryakova Marina , Andreeva Julia , Metelev Mikhail , Lippens Guy , Dubiley Svetlana , Severinov Konstantin
Published: August 2019

Post translational modifications can help maintain the threaded lasso topology of pseudomycoidin.
SANS partial structure factor analysis for determining protein–polymer interactions in semidilute solution
Authors: Huang Aaron , Yao Helen , Olsen Bradley D.
Published: August 2019

Contrast variation small angle neutron scattering experiments reveal the nature of interactions between proteins and polymers in semidilute aqueous solution.
Rubisco activation by wheat Rubisco activase isoform 2β is insensitive to inhibition by ADP
Authors: Perdomo Juan Alejandro , Degen Gustaf E. , Worrall Dawn , Carmo-Silva Elizabete
Published: August 2019

Rubisco activase (Rca) is a catalytic chaperone that remodels the active site, promotes the release of inhibitors and restores catalytic competence to Rubisco. Rca activity and its consequent effect on Rubisco activation and photosynthesis are modulated by changes to the chloroplast environment induced by fluctuations in light levels that reach the leaf, including redox status and adenosine diphosphate (ADP)/adenosine triphosphate (ATP) ratio. The Triticum aestivum (wheat) genome encodes for three Rca protein isoforms: 1β (42.7 kDa), 2β (42.2 kDa) and 2α (46.0 kDa). The regulatory properties of these isoforms were characterised by measuring rates of Rubisco activation and ATP hydrolysis by purified recombinant Rca proteins in the presence of physiological ADP/ATP ratios. ATP hydrolysis by all three isoforms was sensitive to inhibition by increasing amounts of ADP in the assay. In contrast, Rubisco activation activity of Rca 2β was insensitive to ADP inhibition, while Rca 1β and 2α were inhibited. Two double and one quadruple site-directed mutants were designed to elucidate if differences in the amino acid sequences between Rca 1β and 2β could explain the differences in ADP sensitivity. Changing two amino acids in Rca 2β to the corresponding residues in 1β (T358K & Q362E) resulted in significant inhibition of Rubisco activation in presence of ADP. The results show that the wheat Rca isoforms differ in their regulatory properties and that amino acid changes in the C domain influence ADP sensitivity. Advances in the understanding of Rubisco regulation will aid efforts to improve the efficiency of photosynthetic CO2 assimilation.
Age at last birth and risk of developing epithelial ovarian cancer: a meta-analysis
Authors: Wu Yanjun , Sun Wenjun , Xin Xueling , Wang Weijing , Zhang Dongfeng
Published: August 2019

Background: Many epidemiologic studies have explored the association between age at last birth (ALB) and the risk of epithelial ovarian cancer, but the results remain controversial. Methods: A literature search was performed in PubMed, Web of Science, China National Knowledge Infrastructure (CNKI) and WanFang Med Online for relevant articles published up to April 2019. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effect model. Dose–response relationship was assessed by restricted cubic spline model. Results: Thirteen articles with 19,959 cases and 2,451,071 participants were included in our meta-analysis, and we found that ALB was negatively associated with epithelial ovarian cancer. The pooled RR (95% CI) of epithelial ovarian cancer for the highest versus the lowest stratification of ALB was 0.77 (0.65–0.91). Furthermore, significantly negative associations were shown in case–control studies (RR: 0.73; 95% CI: 0.60–0.88), studies conducted in North America (RR: 0.71; 95% CI: 0.60–0.84), studies with adjustment for parity (RR: 0.76; 95%CI: 0.63–0.93), studies with adjustment for tubal ligation (RR: 0.74; 95% CI: 0.58–0.94), in the subgroup analysis. In dose–response analysis, the risk of epithelial ovarian cancer decreased nonlinearly with the increase of ALB, and the negative results become significant when ALB was 22.5 years old. Conclusion: This meta-analysis suggested that ALB was negatively associated with the risk of epithelial ovarian cancer. The risk of epithelial ovarian cancer decreased gradually with the ALB for women.
Hyper-osmolarity environment-induced oxidative stress injury promotes nucleus pulposus cell senescence in vitro
Authors: Xu Jiawei , Li Haopeng , Yang Kai , Guo Shuai , Wang Jie , Feng Chaoshuai , Chen Huayou
Published: August 2019

Nucleus pulposus (NP) cell senescence is involved in disc degeneration. The in situ osmolarity within the NP region is an important regulator of disc cell’s biology. However, its effects on NP cell senescence remain unclear. The present study was aimed to investigate the effects and mechanism of hyper-osmolarity on NP cell senescence. Rat NP cells were cultured in the in situ-osmolarity medium and hyper-osmolarity medium. The reactive oxygen species (ROS) scavenger N-acetylcysteine (NAC) was added along with the medium to investigate the role of oxidative injury. Cell cycle, cell proliferation, senescence associated β-galactosidase (SA-β-Gal) activity, telomerase activity, expression of senescence markers (p16 and p53) and matrix molecules (aggrecan and collagen II) were tested to assess NP cell senescence. Compared with the in situ-osmolarity culture, hyper-osmolarity culture significantly decreased cell proliferation and telomerase activity, increased SA-β-Gal activity and cell fraction in the G0/G1 phase, up-regulated expression of senescence markers (p16 and p53) and down-regulated expression of matrix molecules (aggrecan and collagen II), and increased intracellular ROS accumulation. However, addition of NAC partly reversed these effects of hyper-osmolarity culture on cellular senescence and decreased ROS content in NP cells. In conclusion, a hyper-osmolarity culture promotes NP cell senescence through inducing oxidative stress injury. The present study provides new knowledge on NP cell senescence and helps us to better understand the mechanism of disc degeneration.
Microstrip switchable diplexer based on dual‐mode stub‐loaded stepped‐impedance resonators with three operating states
Authors: Chen C.‐F. , Chen R.‐Y. , Zhou K.‐W. , He Y.‐H.
Published: August 2019

A new three‐state switchable diplexer based on dual‐mode stub‐loaded stepped‐impedance resonators (SL‐SIRs) has been proposed. The three‐state diplexer comprised six SL‐SIRs with a distributed coupling structure. By appropriately adjusting the structural parameters of the SL‐SIRs, a two‐pole filtering response can be implemented at each channel passband. In addition, three p‐i‐n diodes, which were connected to the T‐junction of the input coupled‐line, were used to control the switching between the three operating states. Moreover, each operating state can be switched independently. For the purpose of demonstration, a three‐state switchable diplexer was designed and fabricated using microstrip technology. The simulated results were consistent with the measured results, which indicate that the proposed switchable diplexer not only has a good in‐band performance but also provides good isolation of better than 25 dB between output channels.
Study on the ratio change measurement of 1000 kV HVDC divider based on improved DC voltage summation method
Authors: Li Dengyun , Liu Kaipei , Lei Min , Zhou Feng , Yue Changxi , Yu Jicheng
Published: August 2019

Determining the voltage ratio change is one of the core issues in the traceability of the DC voltage divider. Basing on the previous research results, this study proposes an improved DC voltage summation method to evaluate the voltage division ratio error of 1000 kV DC resistance divider. The principle of the method is to calibrate the voltage divider with rated voltage 2U by using two auxiliary voltage dividers which are with rated voltage U, wherein the high‐voltage (HV) arm and the low‐voltage arm of the auxiliary voltage divider can be separated. Research results show that compared with the conventional method, the method can reduce one measurement variable when determining the divider's ratio change, thus simplifying the calibration process. The voltage ratio of 100 kV measured by the method of this study was well‐verified by the calibration results from the National Institute of Metrology (NIM, China) and Physikalisch‐Technische Bundesanstalt (PTB, Germany). Using the proposed method, the ratio change of DC voltage divider at an applied voltage of 1000 kV was effectively obtained and the uncertainty of 2.5 μV/V was achieved. Research results can provide technical guarantee for the accurate measurement of HVDC magnitude.
Capacity evaluation for LTE applications considering queue overflow
Authors: Alshaikh Ali Muntadher , Esmailpour Amir , Marcus James R.
Published: August 2019

In this study, the authors evaluate the capacity by summation of granted bit rates in their proposed quality of service‐aware scheduling strategy for long term evolution (LTE). To provision differentiation, the scheduling technique prioritises the queues for high priority (HP) applications against their low priority (LP) counterparts. Fairness, on the other hand, is supported by considering queue overflow of LP applications. They utilised the principles of a random variable to derive equations for the capacities offered by their method and used the token bucket technique to address the principle of the guaranteed‐bit‐rate for HP applications, referring to the guaranteed capacity in LTE. Experimental findings confirm that their strategy could extend the capacity granted to LP applications and simultaneously maintain the capacity condition for HP applications. The results also show relative improvement and acceptable degradation in the capacities granted to the LP and HP applications in their scheme when compared with other methods.
Robust optimisation of source power and relay beamforming in multiuser wireless networks
Authors: Rashid Umar , Sarwar Muqaddas , Awan Fahim
Published: August 2019

In this work, a novel design for a highly non‐convex problem of joint optimisation of source power and relay beamforming vector in multi‐user systems is presented. Taking into account imperfect channel‐state information, the design problem is formulated as a non‐convex optimisation problem for the maximisation of the minimum signal‐to‐interference‐plus‐noise ratio across given users. This computationally‐intractable non‐convex problem is exploited for hidden convexity after which a path‐following algorithm with low computational complexity is developed which converges to a local optimal point after a few iterations. Extensive simulation results show that the proposed algorithm of joint design outperforms the alternating optimisations of source power and relay beamforming.
Compressive sensing‐based low‐complexity detector for differential spatial modulation
Authors: Jose Deepak , Sameer S.M.
Published: August 2019

Detection of differential spatial modulation (DSM) needs only the received symbols, unlike spatial modulation that requires channel state information at the receiver. The maximum likelihood (ML)‐based DSM receiver, though works well for a small number of transmit antennas, is computationally prohibitive for higher number of antennas. The hard‐limiter based ML (HL‐ML) receiver has low search complexity in the higher signal‐to‐noise regions only. The authors propose a low‐complexity detection technique using compressive sensing for DSM. The detection involves a two‐step process, by first finding the antenna index number and then the M‐ary phase‐shift keying (MPSK) symbol transmitted from that antenna. After performing a correlation between the past and the present received symbol blocks, the index location of the largest elements of this operation reveals the order of antennas that were activated in a symbol duration. The MPSK symbol is found by a pseudo‐inverse operation on the columns of the past and the present received symbol blocks, corresponding to the time index and antenna number, which is same as the above indices. The proposed receiver achieves a substantial reduction in computational complexity close to 63%, when compared to the HL‐ML receiver and the performance penalty narrows down with higher order MPSK constellations.
Interference management for D2D‐enabled HetNets with imperfect channel estimation
Authors: Maher Engy Aly , El‐Mahdy Ahmed
Published: August 2019

Device‐to‐device (D2D) and heterogeneous networks (HetNets) are two promising technologies to be introduced in the upcoming 5G network, for improving spectral efficiency and decreasing latency. However, sharing the same spectrum resources among different tiers of HetNet raised the interference challenge. In this paper, cross‐tier interference management for underlay D2D users is studied in a heterogeneous macro‐small cell network assuming imperfect channel state information (CSI). The network consists of one macro‐cell with a centered macro‐base Station (MBS) and several small‐cell base stations (SCBS). Two types cellular users are considered; macro‐cell cellular user equipment (MUE) associated with the MBS, and small‐cell cellular user equipment (SUE) linked to SCBS. While two types of D2D users are considered; macrocell D2D (MD) located outside the range of the small cells and cross‐tier D2D user equipment (CD), where each user of the D2D pair belongs to different network tier. Closed form expressions for the D2D optimal power that aim to maximize the coverage probability and the signal‐to‐interference‐noise ratio (SINR) of both links are derived, while guaranteeing the quality of service (QoS) requirements for the cellular user. The effect of channel estimation error on the performance of both D2D and cellular users is evaluated.
Multi‐hop decision gathering scheme for target‐detection wireless sensor networks
Authors: Althunibat Saud , Al Tarawneh Ziyad
Published: August 2019

Most of the energy consumed in target‐detection wireless sensor networks (WSNs) is due to the decision gathering process. As such, several energy‐efficient decision gathering schemes have been proposed to improve energy efficiency. In this study, a new multi‐hop decision gathering scheme for target‐detection WSNs is presented. The proposed scheme creates paths to gather the nodes' decisions, where each path includes a set of nodes. Nodes in the same path cooperate to deliver their decisions by using multi‐hop transmissions. At each hop, the relay node combines the received decisions with its own decision and uses a higher modulation order to forward them to the next node in the path. Two different setup scenarios are considered to evaluate the proposed scheme, namely, fixed transmit power scenario and fixed bit error rate scenario. In the former scenario, results demonstrate that the proposed scheme achieves better error rate at short hop distances when compared to the conventional single hop scheme. On the other hand, results of the fixed bit error rate scenario show that a significant amount of the saved power can be attained by the proposed scheme with a slight loss in the decision error rate.
An interference‐aware energy‐efficient routing algorithm with quality of service requirements for software‐defined WSNs
Authors: Ding Zhaoming , Xing Song , Yan Feng , Xia Weiwei , Shen Lianfeng
Published: August 2019

To address the energy‐efficient (EE) routing problem in software‐defined wireless sensor networks (SDWSNs), in this study, a centralised routing algorithm, namely, the interference‐aware EE routing algorithm (IA‐EERA), is proposed to extend the network lifetime (NL) in SDWSNs. Both the link quality of service requirements and the balance between the link energy loads are considered in the proposed IA‐EERA when selecting the EE relays. Concretely, the IA‐EERA comprises the EE relay selection (RS) and the centralised relay scheduling schemes, which are responsible for generating a valid link set with RS priorities and scheduling the eligible relay nodes with expected link rates from the valid link set, respectively. For supporting the network compatibility and scalability, we propose a hierarchical SDWSN based network architecture, upon which the IA‐EERA can be devoted to solving the EE routing problem in the relay layer of SDWSN. Simulation results show that for one data source without interference, the proposed IA‐EERA can significantly improve the NL compared with the traditional routing algorithm utilising the energy efficiency maximisation. For multiple data sources incurring interference at nodes, the IA‐EERA is able to reduce the NL‐dropping rate by adjusting the interference‐aware parameter that affects the RS priorities
M‐ary code‐shifted differential chaos shift keying with in‐phase and quadrature code index modulation
Authors: Cai Xiangming , Xu Weikai , Wang Lin , Xu Fang
Published: August 2019

In this study, an M‐ary code‐shifted differential chaos shift keying system with in‐phase and quadrature code index modulation (I/Q‐CIM‐CS‐MDCSK) is presented. In the proposed system, the information bits are conveyed not only by the M‐ary constellation symbols, but also by the specific Walsh codes indices corresponding to the in‐phase and quadrature branches of M‐ary information bearing signals. Since the reference signal and the multiple M‐ary information bearing signals are overlapped and transmitted within the identical time slot in a parallel manner, the spectral efficiency of the I/Q‐CIM‐CS‐MDCSK system is enhanced significantly. In addition, the analytical bit error rate (BER) expressions for the presented system are derived under the additive white Gaussian noise and multipath Rayleigh fading channels. Finally, the BER performance of the proposed system is compared to other chaotic communication systems. The results manifest that the I/Q‐CIM‐CS‐MDCSK system is a promising and competitive chaotic communication scheme.
Exact closed‐form capacity and outage probability of physical layer security in shadowed fading channels
Authors: Al‐Hmood Hussien , Al‐Raweshidy Hamed
Published: August 2019

In this study, the secrecy performance of physical layer when both the main and wiretap channels undergo shadowed fading conditions is analysed. In particular, the average secrecy capacity, secure outage probability (SOP), the lower bound of SOP (SOP), and the probability of strictly positive secrecy capacity are derived by using the classic Wyner's wiretap model. Two different scenarios for the fading parameters, namely, and m, which represent the real extension of the number of the multipath clusters and the shadowing index, respectively, have been studied. These parameters are chosen first as arbitrary numbers, thus the performance metrics are given in exact closed‐form in terms of the extended generalised bivariate Fox's H‐function that has been widely implemented in the open literature using various software packages. In the second scenario, both the fading parameters are assumed to be integer numbers to obtain the derived results in simple exact closed‐form mathematically tractable expressions in terms of some analytic functions. The numerical results of this analysis are verified via the Monte Carlo simulations.
Magnetic composites Fe3O4@SiO2@PILs as sorbents for efficient denitrogenation of fuel oil
Authors: Wang Feng , Li Jie , Xu Long , Jiang Feng , Zhang Jianfeng
Published: August 2019

In this work, the study of synthesis and denitrogenation of magnetic polymeric ionic liquids (PILs) for N‐compounds in simulated oils and diesel are reported. Three functionalised magnetic particles, Fe3O4@SiO2@PILs with side alkyl chain of C2, C4 and C6, respectively, were prepared by grafting PILs on the surface of silica‐coated Fe3O4. Fourier transform infrared spectra, thermogravimetric analysis, X‐ray diffraction and scanning electron microscopy were carried out to characterise the structure of Fe3O4@SiO2@PILs. It has shown that Fe3O4@SiO2@ PILs possess precious merits for sorbents, such as regular morphology, good stability and magnetic properties. Denitrogenation experiments of simulated oils demonstrate that Fe3O4@SiO2@ PILs show better denitrogenation efficiency of basic N‐compounds than neutral N‐compounds. The effects of temperature, reaction times, ratio of reagent to oil on denitrogenation for simulated oils were explored, and 92.1% denitrogenation efficiency was obtained to remove quinoline from simulated oils. Denitrogenation of Fe3O4@SiO2@PILs in diesel leads to 84.3% denitrogenation efficiency, and it can remain 82.5% denitrogenation efficiency after five times of recycles. Compared with other similar sorbents, Fe3O4@SiO2@PILs show competitive performances to eliminate organic N‐compounds. It is hopeful that Fe3O4@SiO2@PILs can be promising sorbents for purification of liquid fuel by adsorptive denitrogenation.
Effects of alkali metal on solution loss and coke degradation
Authors: Yu Dongsheng , Guo Rui , Liang Yinghua , Liu Lianji , Chen Peng
Published: August 2019

To research the effect of alkali metals on the solution-loss rate and coke strength after reaction, potassium and sodium vapors were prepared by a high-temperature thermal-reduction method, and the thermal properties of four industrial cokes that absorbed potassium and sodium vapor were studied. The thermal properties include the traditional thermal-property indices, coke reactive index and coke strength after reaction, and the coke strength after a 25% mass loss, which is obtained by a continuous thermogravimetric test. Results show that because of the different adsorption mode, the catalytic effect of potassium and sodium is different. During the early stages of the solution-loss reaction, the reaction rate of the potassium-rich coke is higher than that of the sodium-rich coke, but the reaction rate decreases rapidly. The reaction rate of the sodium-rich coke in the later stage of the reaction is higher than that of the potassium-rich coke. The coke strength after reaction of the alkali-rich coke is low, mainly because of the high carbon-solution loss. The coke strength after the 25% mass loss of potassium-rich coke was higher than that of the original coke because the solution reaction was closer to the surface reaction.
Simple liver cysts and cystoid lesions in hepatic alveolar echinococcosis: a retrospective cohort study with Hounsfield analysis
Authors: Engler Agata , Shi Rong , Beer Meinrad , Schmidberger Julian , Kratzer Wolfgang , Barth Thomas F. E. , Grimm Johannes , Hillenbrand Andreas , Henne-Bruns Doris , Gruener Beate , Beer Ambros J. , Graeter Tilmann
Published: August 2019

Background. Alveolar echinococcosis (AE) is a rare zoonosis caused by the larval stage of the tapeworm Echinococcus multilocularis. AE lesions affect the liver in more than 98% of cases. AE lesions have various morphological characteristics that are described in the Echinococcus multilocularis Ulm classification for computed tomography (EMUC-CT). One of these characteristics is a cystoid portion. The aim of the study was to compare the density of simple hepatic cysts with cystoid portions of AE lesions classified on the basis of the EMUC-CT. Results. Hounsfield Unit (HU) measurements of the cystoid portions of all EMUC-CT type I–IV AE lesions (n = 155) gave a mean of 21.8 ± 17.6, which was significantly different from that of 2.9 ± 4.5 for the simple hepatic cysts (p < 0.0001). The difference between each of the individual AE types and simple hepatic cysts was also significant. In addition, the HU values of the cystoid portions in types I, II and IIIa/b and simple cysts were each significantly different from type IV (p < 0.0001). The HU measurements in type IV presented by far the highest mean. Conclusions. The significantly higher density measured in the cystoid portions of hepatic AE lesions offers a good means of differentiation from simple hepatic cysts.
The Past, Present and Future of Facial Plastic and Reconstructive Surgery: Facelift
Authors: Floyd Elizabeth , Perkins Stephen W.
Published: August 2019

Facelift or rhytidectomy has been performed in some form for over 100 years. This article seeks to explore the evolution of this surgical procedure, focusing on the advances of the most recent 40 years. From minimal intervention to aggressive techniques and back to the minimally invasive again, the authors follow the journey of surgical intervention for facial rejuvenation and discuss some thoughts for the future.
Preoperatively Identified Sarcopenia Leads to Increased Postoperative Complications, Hospital and ICU Length of Stay in Autologous Microsurgical Breast Reconstruction
Authors: Pittelkow Eric M. , DeBrock Will C. , McLaughlin Briana E. , Hassanein Aladdin H. , Socas Juan , Lester Mary E. , Duquette Stephen P.
Published: August 2019

Background Sarcopenia is a condition characterized by the loss of skeletal muscle mass and strength. Recently, there has been a tremendous amount of research into the prognostic value of sarcopenia in surgical outcomes. The purpose of this study was to compare postoperative outcomes in free flap breast reconstruction in patients with and without sarcopenia.

Methods One hundred three patients who underwent autologous breast reconstruction from 2013 to 2016 were studied. The cross-sectional area (CSA) of skeletal muscle was measured from preoperative computed tomography images at L3 using the National Institutes of Health ImageJ software. CSA was then normalized to patient stature by dividing CSA by height (cm2/m2). A previously published skeletal muscle index cutoff of 38.5 cm2/m2 was used to define sarcopenia. Intraoperative and postoperative surgical outcomes were recorded retrospectively. Outcomes were analyzed using multivariate, univariate, and regression statistics.

Results Eight of the 103 (7.8%) patients were found to have sarcopenia. Sarcopenia was associated with a statistically significant increase in flap site delayed healing (37.5% vs. 20%, p = 0.046), take back to the operating room (25% vs. 11.6%, p = 0.05), intensive care unit length of stay (1.5 vs. 0.02 days, p < 0.0005), and hospital length of stay (8.38 vs. 5.49 days, p < 0.0005) when compared with patients without sarcopenia. There were no significant differences in flap loss, surgical site infection, hematoma, seroma, donor site delayed healing, intraoperative complications, and number of revision surgeries.

Conclusion Sarcopenia is significantly associated with increased complications in patients undergoing free flap breast reconstruction. Further investigation into the biochemical and physiologic changes associated with sarcopenia is needed.