bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prior Uterine Evacuation and the Risk of Short Cervical Length: A Retrospective Cohort Study
Authors: Boelig Rupsa C. , Villani Michela , Jiang Eva , Orzechowski Kelly M. , Berghella Vincenzo 
Published: January 2018

ObjectivesTo determine whether a prior uterine evacuation procedure is associated with an increased risk of short cervical length (≤20 mm) in women without prior spontaneous preterm birth.MethodsThis work was a retrospective cohort study from January 2012 to December 2014 of singletons without prior spontaneous preterm birth with cervical length screening between 18 weeks and 23 weeks 6 days. Women with a prior miscarriage/abortion were excluded if management (medical, surgical, or expectant) was not specified. Prior uterine evacuation was defined as dilation and curettage or dilation and evacuation of a spontaneous or induced abortion. The primary outcome was the risk of short cervical length (≤20 mm) among women with and without 1 of more prior uterine evacuations at any gestational age, assessed by the odds ratio and adjusted odds ratio for confounders.ResultsOf 2672 women included, 714 (27%) had at least 1 prior uterine evacuation. The overall incidence of short cervical length in the cohort was 1% (n = 27). Women with at least 1 prior uterine evacuation were more likely to be African American (64% versus 41%; P < .001), smoke (14% versus 8%; P < .001), have a higher body mass index (mean ± SD, 28.1 ± 7.1 versus 26.8 ± 7.1 kg/m2; P < .001), and have had prior full‐term delivery (60% versus 41%; P < .001). Women with at least 1 prior uterine evacuation had a significantly higher incidence of short cervical length (2% versus 0.7%; P = .003; odds ratio, 2.99 [95% confidence interval, 1.40–6.40]). After adjustment for confounders, prior uterine evacuation remained a source of increased risk of short cervical length (adjusted odds ratio, 2.63 [95% confidence interval, 1.19–5.80]).ConclusionsAlthough the overall incidence of short cervical length is low (1%–2%), women with at least 1 prior uterine evacuation have at least a 2‐fold increased risk of a short second‐trimester cervical length compared to women without a prior uterine evacuation.
Role of Elastography in Axillary Examination of Patients With Breast Cancer
Authors: Chang Wanying , Jia Wanru , Shi Junni , Yuan Congcong , Zhang Yuzhu , Chen Man 
Published: January 2018

ObjectivesThis study aimed at exploring the role of ultrasound (US) elastography in the diagnosis of the axillary lymph node status in patients with breast cancer.MethodsWe analyzed 140 visible axillary lymph nodes on conventional US imaging. All of them underwent elastography. Five conventional US features were adopted to assess axillary lymph nodes: longitudinal diameter, longitudinal‐to‐transverse diameter ratio, cortical thickness, status of the hilum, and vascular pattern. As for elastography, the proportion of the hard area within each lymph node was estimated visually. The lymph node was defined as positive on elastography when the proportion was 50% or greater. Meanwhile, disjunctive and conjunctive combinations of US and elastography were adopted to evaluate the lymph nodes. The histopathologic diagnosis was regarded as the reference standard.ResultsThe sensitivity, specificity, and accuracy were 76.92%, 87.10%, and 81.43%, respectively, for conventional US and 84.62%, 83.87%, and 84.29% for the disjunctive combination. The conjunctive combination had specificity of 100% and a positive predictive value of 100%, whereas the sensitivity was low.ConclusionsElastography can improve the sensitivity when disjunctively combined with conventional US for diagnosis of the axillary lymph node status. Despite the low sensitivity, the conjunctive combination of US and elastography can improve the positive predictive value on a large scale. Elastography is a useful adjuvant tool in addition to conventional US for the preoperative assessment of axillary lymph nodes in patients with breast cancer.
Use of Hysterosalpingo‐Foam Sonography for Assessment of the Efficacy of Essure Hysteroscopic Sterilization
Authors: Rosič Maja , Žegura Branka , Vadnjal Đonlagić Sabina 
Published: January 2018

ObjectivesHysterosalpingo‐foam sonography (HyFoSy) has been suggested to be a possible less invasive alternative to hysterosalpingography (HSG), which is the reference standard for confirmation of tubal occlusion after Essure (Bayer AG, Leverkusen, Germany) hysteroscopic sterilization. The purpose of our study was to evaluate the accuracy of HyFoSy compared to HSG for confirmation of tubal occlusion after Essure hysteroscopic sterilization.MethodsA prospective study included 90 patients who underwent Essure hysteroscopic sterilization. Twelve weeks after the sterilization, 2‐dimensional transvaginal ultrasonography was performed to assess the microinsert position and was followed by HyFoSy and HSG for evaluation of tubal occlusion. Patients with patent fallopian tubes on HSG were scheduled for additional HSG procedures at 3‐month intervals until tubal occlusion was documented.ResultsOf 90 enrolled patients, 86 patients with 170 fallopian tubes underwent the complete imaging protocol. Tubal occlusion was evaluated by HyFoSy as an index test and HSG as a reference standard. The accuracy of HyFoSy was 97.1% (95% confidence interval [CI], 93%–99%). The sensitivity and specificity were 100% (95% CI, 97%–100%) and 54.6% (95% CI, 23%–83%), whereas the positive and negative predictive values were 97.0% (95% CI, 93%–99%) and 100% (95% CI, 42%–100%), respectively. No long‐term complications were reported for HyFoSy or HSG.ConclusionsGiven that the concordance rate for tubal occlusion between HyFoSy and HSG was not 100%, an occluded fallopian tube on HyFoSy should be confirmed by HSG, which remains the reference standard for confirmation of tubal occlusion after Essure hysteroscopic sterilization.
Bridging the molecular divide: alcohol‐induced downregulation of PAX9 and tumour development
Authors: Fujihara Kenji Mark , Clemons Nicholas James 
Published: January 2018

AbstractThe pathogenesis of oro‐oesophaeal squamous cell carcinoma is causally linked to the consumption of alcohol. Beyond the carcinogenic effects of ethanol and its metabolites via DNA damage, the precise mechanisms by which alcohol drives tumourigenesis remain to be fully elucidated. A novel contributor now revealed is aberrant differentiation and proliferation mediated by suppression of PAX9, a key regulator of normal squamous maturation in oro‐oesophageal tissues. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Metallic Fumes at Indoor Military Shooting Ranges: Lead, Copper, Nickel, and Zinc in Different Fractions of Airborne Particulate Matter
Authors: Orru Hans , Pindus Mihkel , Harro Haldo‐Rait , Maasikmets Marek , Herodes Koit 
Published: January 2018

AbstractSmall firearm shooting emits residues of energetic materials as well as heavy metals of different particle sizes into the air, posing a risk to human health. The current study assessed concentrations of Pb, Cu, Ni and Zn in 14 different size fractions of particulate matter at indoor military shooting ranges. Air samples were collected using ELPI+ over two hour period and filters analysed with ICP‐MS and ICP‐OES.
Choosing non‐redundant representative subsets of protein sequence data sets using submodular optimization
Authors: Libbrecht Maxwell W. , Bilmes Jeffrey A. , Noble William Stafford 
Published: January 2018

AbstractSelecting a non‐redundant representative subset of sequences is a common step in many bioinformatics workflows, such as the creation of non‐redundant training sets for sequence and structural models or selection of “operational taxonomic units” from metagenomics data. Previous methods for this task, such as CD‐HIT, PISCES, and UCLUST, apply a heuristic threshold‐based algorithm that has no theoretical guarantees. We propose a new approach based on submodular optimization. Submodular optimization, a discrete analogue to continuous convex optimization, has been used with great success for other representative set selection problems. We demonstrate that the submodular optimization approach results in representative protein sequence subsets with greater structural diversity than sets chosen by existing methods, using as a gold standard the SCOPe library of protein domain structures. In this setting, submodular optimization consistently yields protein sequence subsets that include more SCOPe domain families than sets of the same size selected by competing approaches. We also show how the optimization framework allows us to design a mixture objective function that performs well for both large and small representative sets. The framework we describe is the best possible in polynomial time (under some assumptions), and it is flexible and intuitive because it applies a suite of generic methods to optimize one of a variety of objective functions.
Highly Selective β‐Hydride Elimination in the Pd‐Catalyzed Cross‐Coupling of N‐Tosylhydrazones with Benzyl Bromides
Authors: Sun Zhenze , Du Chaoqun , Liu Ping , Wei Yu , Xu Liang , Dai Bin 
Published: January 2018

AbstractIn Pd‐catalyzed cross‐coupling reactions between tosylhydrazones and organohalides, the competitive β–H elimination of palladium complex intermediate generated through palladium‐carbene complex's migratory insertion is usually avoided by combining two specific coupling partners, in which only one contains a β‐H. To address this limitation, herein we present cross‐coupling reactions between benzyl bromides and tosylhydrazones derived from benzocyclic ketones. Benzyl‐substituted dihydronaphthalenes and 1H‐indenes can be obtained in up to 88% yields and 25:1 selectivity for the cyclic olefin via this method. DFT studies were performed to elucidate the reaction mechanism. The β‐H elimination process, which follows the migratory insertion of Pd carbene intermediates, favours the abstraction of hydrogen atoms on the cyclic skeletons and results in the observed regioselectivity.
Comparative Study of Catalytic Systems Formed by Palladium and Acyl‐Substituted Imidazolium Salts
Authors: Gisbert Patricia , Trillo Paz , Pastor Isidro M. 
Published: January 2018

AbstractAmino amides, which are readily accessible from amino acids, were used in the preparation of both monoamido and diamido functionalized imidazolium salts in very straightforward protocols. Different catalytic systems formed with palladium(II) acetate and acyl functionalized imidazolium salts were tested in the Matsuda‐Heck reaction. The comparative study revealed that the presence of one carbamoyl moiety in the N‐heterocyclic carbene precursor is more beneficial during the catalytic process. Thus, better activity was observed with the catalytic system formed using 3‐benzyl‐1‐(N‐phenylcarbamoylmethyl)imidazolium chloride in a 1:1 metal/ligand ratio. Moreover, this fact was evidenced by means of UV/vis studies.
Chitosan‐Derived NiO‐Mn2O3/C Nanocomposites as Non‐Precious Catalysts for Enhanced Oxygen Reduction Reaction
Authors: Chhetri Bijay P. , Parnell Charlette M. , Wayland Hunter , RanguMagar Ambar B. , Kannarpady Ganesh , Watanabe Fumiya , Albkuri Yahya M. , Biris Alexandru S. , Ghosh Anindya 
Published: January 2018

AbstractNiO‐Mn2O3/C nanocomposite was synthesized from chitosan, a renewable biopolymer, NiO and MnO2 and pyrolyzed at 500 °C under nitrogen. The morphology of material was characterized with various microscopic analyses. The graphitic carbon showed metal nanoparticles dispersed on the nanocomposite that could be clearly differentiated. X‐ray photoelectron spectroscopy indicated the Mn species reduced from +4 to +3 oxidation state, while Ni species remained as NiO, which was further supported by X‐ray diffraction. The electrochemical behavior of NiO‐Mn2O3/C toward oxygen reduction reaction (ORR) in alkaline medium was investigated via cyclic voltammetry (CV). CVs revealed a ORR peak at 0.67 V vs. RHE with significantly high current density. Hydrodynamic studies indicated that NiO‐Mn2O3/C catalyzed ORR via a four‐electron reduction pathway. A high rate constant in the order of magnitude of 106 mol−1s−1 was obtained for ORR. This low‐cost, environmentally friendly and stable ORR catalyst derived from chitosan and doped with metal oxides proved to be a promising electrocatalyst for ORR and could alternatively find its application in alkaline fuel cells (AFCs).
Preparation and Structure Analysis of Three New Copper Complexes of Mellitic Acid With 4,4′‐Bipyridine and 1,3‐bis(4‐pyridyl)Propane
Authors: Shimpi Manishkumar R. , Giri Lopamudra , Pedireddi Venkateswara Rao 
Published: January 2018

AbstractCoordination complexes, [Cu2(H2L)(bpy)2]⋅2H2O, (1 a), [Cu(H3L)2(H2O)4]⋅(H2bpypa)2⋅6H2O, (2 a) and [Cu(H3L)4][Cu(H2O)6]⋅(H2bpypa)4⋅20H2O, (2 b), of mellitic acid, H6L, with 4,4′‐bipyrdine, (bpy), and 1,3‐bis(4‐pyridyl)propane, (bpypa), have been prepared and the three‐dimensional structures are established by single crystal X‐ray diffraction unequivocally. The complex 1 a was prepared following hydrothermal method, while the complexes 2 a and 2 b were obtained concomitantly from an aqueous solution at room temperature. In the crystals of 1 a, both acid and the aza‐donors form coordination bonds with metal ions, while in 2 a and 2 b coordination bonding prevails between metal and acid molecules only, with aza‐donor molecules remain intact without coordinating to metal species. Further, 1 a and 2 b are noted to be yielding a host‐guest network, whereas 2 a forms planar sheets that are stacked in three‐dimensional arrangement.
“A Tale of Two Structures”: The Stacks and Ts of Borazine and Benzene Hetero and Homo Dimers
Authors: Verma Kanupriya , Viswanathan K. S. 
Published: January 2018

AbstractThe heterodimers of borazine and benzene were studied using matrix isolation infrared spectroscopy and ab initio calculations, for an eventual comparison with the corresponding homodimers of the submolecules. The homo and hetero dimers are expected to show the stacked and T‐shaped structures as a general class of geometries; a study which promises to present an interesting comparison of the landscape of the homo and the heterodimers. Computations on the heterodimers were performed at the MP2 and M06‐2X levels of theory using aug‐cc‐pVDZ basis set. The heterodimer manifested both the T‐shaped and stacked structures, with the former being the global minimum. The T‐shaped structure itself showed two isoenergetic variations: one was the T‐NH structure, where the N−H of borazine pointed towards the center of the benzene ring and the second was the NH…C structure, where the N−H pointed towards a carbon atom of benzene; in short, the borazine formed the stem and the benzene formed cap of the T. We were able to discern both the T‐shaped structures in our matrix isolation experiments. A third geometry, the parallel displaced stacked structure, was indicated to be a local minimum, which however was not observed in our experiments. AIM, LMO‐EDA and NBO analysis was carried out to explore the nature of interactions in the various structures.
Wind‐induced fatigue of large HAWT coupled tower–blade structures considering aeroelastic and yaw effects
Authors: Ke Shitang , Wang Tongguang , Ge Yaojun , Wang Hao 
Published: January 2018

SummaryAn efficient approach for predicting wind‐induced fatigue in large horizontal axis wind turbine coupled tower–blade structures subject to aeroelastic and yaw effects is presented. First, aerodynamic loads under yaw conditions are simulated based on the harmonic superposition method and modified blade element momentum theory, in which wind shear, tower shadow, tower–blade interactions, aeroelastic, and rotational effects are taken into account. Then, a nonlinear time‐history of wind‐induced responses under simulated aerodynamic loads is obtained. Finally, based on these results, wind‐induced fatigue damage and lifespan are predicted according to linear cumulative damage theory. For completeness, the influences of mean wind speed, aeroelasticity, and yaw angle on horizontal axis wind turbine fatigue life are discussed. The results indicate that the aerodynamic loads and residual fatigue life can be estimated accurately by the proposed model, which can be used to simulate the 3D wind fields of wind turbines under given wind conditions. The wind energy of the wind turbine blade is mainly concentrated at its edge and is weaker at the hub. Estimation of wind turbine fatigue life is therefore suggested to be based on the component with the shortest life, being the blade root. Furthermore, yaw conditions significantly shorten fatigue life and should not be ignored. Fatigue life is also rather sensitive to mean wind speed.
History of genome editing in yeast
Authors: Fraczek Marcin G. , Naseeb Samina , Delneri Daniela 
Published: January 2018

AbstractFor thousands of years humans have used the budding yeast Saccharomyces cerevisiae for the production of bread and alcohol; however, in the last 30–40 years our understanding of the yeast biology has dramatically increased, enabling us to modify its genome. Although S. cerevisiae has been the main focus of many research groups, other non‐conventional yeasts have also been studied and exploited for biotechnological purposes. Our experiments and knowledge have evolved from recombination to high‐throughput PCR‐based transformations to highly accurate CRISPR methods in order to alter yeast traits for either research or industrial purposes. Since the release of the genome sequence of S. cerevisiae in 1996, the precise and targeted genome editing has increased significantly. In this ‘Budding topic’ we discuss the significant developments of genome editing in yeast, mainly focusing on Cre‐loxP mediated recombination, delitto perfetto and CRISPR/Cas.
Trade and the Spillovers of Transnational Terrorism
Authors: de Sousa José , Mirza Daniel , Verdier Thierry 
Published: January 2018

Summary
We examine the impact of transnational terrorism diffusion on security and international trade. To counter the diffusion of transnational terrorism, targeted governments implement security measures against countries where terror could potentially diffuse. Since security measures raise trade costs, we argue that countries, close enough to those from where terror originates, should experience negative spillovers on their trade. We find evidence for this hypothesis in our data. We show that the closer a country is to a source of terrorism, the higher the negative spillovers on its trade.
Who opposes immigrants’ integration into the labor market? The Swiss case
Authors: Müller Tobias , Tai Silvio H. T. 
Published: January 2018

Summary
First, we spell out a political-economy model, based on segmented labor markets, which explains why a guest-worker system is preferred to a non-discriminatory immigration regime and why measures to improve the integration of low-skill immigrants tend to be opposed subsequently. The model also predicts that attitudes towards the integration of immigrants are positively related to education. Second, we examine the empirical evidence on attitudes towards the integration of immigrants. Our findings from Swiss data are consistent with the prediction of the theoretical model. Both economic and non-economic factors seem to matter in the positive relationship between attitudes and education.
The cycle of development in Africa: A story about the power of economic ideas
Authors: Paldam Martin 
Published: January 2018

Summary
During the last 60 years development in Sub-Sahara Africa has had three main phases — P1, P2 and P3 — divided by kinks in 1972 and in 1994. P1 and P3 had fairly satisfactory growth, but P2 had negative growth. This cyclical growth path has to be explained by variables with a similar path. A set of socio-economic variables representing 11 hypotheses is considered. Some of these hypotheses have been proposed to explain the low growth of Africa, while most are meant to explain the growth tragedy of P2. Most of the variables have paths with no relation to the cycle, but the path corresponds to the shifts in the dominating development strategy. At the end of P1 the main policy-package in Africa became the one of African socialism. It led to large scale rent seeking, inefficiency and economic regression. At the end of P2 policies were adjustment towards a more market based system and growth resumed.
Free mobility with the EU and immigration of North American brains to Switzerland: What consequences?
Authors: Gross Dominique M. 
Published: January 2018

Summary
In 2002, Switzerland started to implement free mobility with the European Union and simultaneously immigration rules for citizens from the rest of the world became more stringent. Only skilled workers could be hired from third countries and employers had to give priority in hiring to Swiss and European skilled applicants. This paper shows that the new legislation has strongly adversely affected the size of high-skill immigration from North America. Also, incentives to leave those countries have changed as North Americans are more inclined to consider home professional networks and financial opportunities. The consequence is less geographical heterogeneity in immigrants which may decrease Swiss firms’ ability to gain information about non-European markets and increase their entry cost into those markets.
Demand for reserves and the central bank’s management of interest rates
Authors: Kraenzlin Sébastien , Schlegel Martin 
Published: January 2018

Summary
The implementation of monetary policy is prevalently done by interest rate targeting with a short term market rate serving as operational target. The instruments for achieving the operational target are the provision of reserves and the interest rate charged in these transactions. This paper presents a model for the estimation of the demand curve for reserves, derived from the central bank’s fixed rate tender auction and the interbank money market. Using data from Switzerland, the slope of the demand curve is estimated. Furthermore, properties of the demand curve such as the slope patterns in the course of a maintenance period and the slope in different monetary regimes are assessed. We find a steeper demand curve towards the end of the maintenance period and an increasing slope when the general interest rate level is high. Further, we investigate the role of the Swiss National Bank’s (SNB) interest rate in the fixed rate tender auctions. There is evidence that the SNB uses its auction rate to guide the interbank market rate.