bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temperature‐related geographical shifts among passerines: contrasting processes along poleward and equatorward range margins
Authors: Coristine Laura E. , Kerr Jeremy T. 
Published: October 2015

AbstractClimate change is causing widespread geographical range shifts, which likely reflects different processes at leading and trailing range margins. Progressive warming is thought to relax thermal barriers at poleward range margins, enabling colonization of novel areas, but imposes increasingly unsuitable thermal conditions at equatorward margins, leading to range losses from those areas. Few tests of this process during recent climate change have been possible, but understanding determinants of species’ range limits will improve predictions of their geographical responses to climate change and variation in extinction risk. Here, we examine the relationship between poleward and equatorward range margin dynamics with respect to temperature‐related geographical limits observed for 34 breeding passerine species in North America between 1984–1988 and 2002–2006. We find that species’ equatorward range margins were closer to their upper realized thermal niche limits and proximity to those limits predicts equatorward population extinction risk through time. Conversely, the difference between breeding bird species’ poleward range margin temperatures and the coolest temperatures they tolerate elsewhere in their ranges was substantial and remained consistent through time: range expansion at species’ poleward range margins is unlikely to directly reflect lowered thermal barriers to colonization. The process of range expansion may reflect more complex factors operating across broader areas of species’ ranges. The latitudinal extent of breeding bird ranges is decreasing through time. Disparate responses observed at poleward versus equatorward margins arise due to differences in range margin placement within the realized thermal niche and suggest that climate‐induced geographical shift at equatorward range limits more strongly reflect abiotic conditions than at their poleward range limits. This further suggests that observed geographic responses to date may fail to demonstrate the true cost of climate change on the poleward portion of species’ distributions. Poleward range margins for North American breeding passerines are not presently in equilibrium with realized thermal limits.
Reduced Phosphomolybdates as Molecular Catalysts for Hexavalent Chromium Reduction
Authors: Gong Kaining , Liu Yunping , Wang Weijie , Fang Tim , Zhao Chuan , Han Zhangang , Zhai Xueliang 
Published: October 2015

AbstractHybrid phosphomolybdates consisting of highly reduced {MnII(PV4MoV6O31)2} clusters have been reported as heterogeneous molecular catalysts for the reduction of toxic CrVI to nontoxic CrIII using formic acid (FA) as the reducing agent. The experimental results show that these types of nonprecious hybrids are highly active for the catalytic reduction of CrVI under mild conditions. In comparison with noble metal Pt/Pd nanoparticle (NP) catalysts that are widely used for the reaction, the phosphomolybdate hybrids are inexpensive and easy to prepare. Importantly, their structures can be designed and optimised. This study highlights noble metal‐free phosphomolybdates as a novel type of heterogeneous catalyst for the treatment of CrVI‐containing wastewater.
Solvothermal Reactions in and with Nitriles
Authors: Thiele Günther , Wagner Bettina , Dehnen Stefanie 
Published: October 2015

AbstractSolvothermal reactions and in situ reductions in nitriles yield a variety of new metal complexes and organometallic compounds including ligands of dimers, trimers, and tetramers of the organic solvent upon (oxidative) C–C and/or C–N bond formation and destruction.
Contrasting Reactivity of CS2 with Cyclic vs. Acyclic Amidines
Authors: Ang M. Trisha C. , Phan Lam , Alshamrani Aliyah K. , Harjani Jitendra R. , Wang Ruiyao , Schatte Gabriele , Mosey Nicholas J. , Jessop Philip G. 
Published: October 2015

AbstractThe interaction between carbon dioxide (CO2) and amidines such as 1,8‐diazabicyclo[5.4.0]undecane (DBU) has been extensively studied, but the reaction of isovalent CS2 with such bases has been largely ignored, apart from a single crystallography report. Acyclic acetamidines are cleaved by CS2 at room temperature to give an isothiocyanate and a thioacetamide. Because the pathway to that cleavage involves a rotation that is difficult for cyclic amidines, the reaction of CS2 with cyclic amidines produces an entirely different product: a cyclic carbamic carboxylic trithioanhydride structure. The path to that product involves sp3 C‐H activation leading to the formation of a new C–C bond at a carbon α to the central carbon of the amidine group. Alkylation and ring‐opening of the cyclic carbamic carboxylic trithioanhydride has also been demonstrated under ambient conditions.
Hypervalent‐Iodine‐Mediated Synthesis of 1,2‐Dispirodienones: Experimental and Theoretical Investigations
Authors: Hromjakova Tatiana , Retailleau Pascal , Grimaud Laurence , Gandon Vincent , Chabaud Laurent , Guillou Catherine 
Published: October 2015

AbstractThe oxidation of phenol acetanilides mediated by hypervalent iodine is described. The transformation proceeds through the formation of a carbocationic species that evolves either into a [6,5,6]‐tricyclic compound (1,2‐dispirodienone) or a [6,6,6]‐tricyclic compound (aryl spirodienone). In most examples, the 1,2‐dispirodienones are obtained in good yields. In some cases, depending on the substitution pattern of the phenol acetanilides and the reaction conditions, aryl spirodienones are formed. We performed electrochemical experiments on a 1,2‐dispirodienone to study its redox properties. These data provide evidence that the 1,2‐dispirodienone can ring‐open and ring‐close under redox conditions. The hypervalent‐iodine‐mediated oxidation of phenol acetanilides to 1,2‐dispirodienones was rationalized on the basis of density functional theory (DFT) calculations. In addition, these DFT computations suggest that the formation of the aryl spirodienones occurs by a stepwise reaction pathway, which first involves an ipso attack to yield a [6,5,6]‐tricyclic carbocationic intermediate and then a 1,2‐sigmatropic shift of the bond that connects the two six‐membered rings.
The Poisoning of Pyrite Surface upon Xanthate Adsorption by Cyanide in Mildly Acidic Media
Authors: Guo Bao 
Published: October 2015

AbstractXanthate adsorbs on pyrite surface at mildly acidic pH, rendering mineral surface hydrophobic. By far, the electrochemical behavior of pyrite exposed to cyanide‐bearing solution has been reported in alkaline media. The impact of cyanide on the chemisorption of xanthate on pyrite in mildly acidic media is unclear. The present study clearly pictured the interfacial processes in pyrite‐xanthate‐cyanide system at pH 5 via methods of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It is determined that cyanide blocks the formation of xanthate layer on pyrite surface over a broad range of potential, although the oxidation of xanthate in solution almost remains unaffected. The pyrite surface upon xanthate adsorption is poisoned by cyanide with the formation of iron cyanide complex.
Melamine‐modified Boron‐doped Diamond towards Enhanced Detection of Adenine, Guanine and Caffeine
Authors: Niedziałkowski P. , Bogdanowicz R. , Zięba P. , Wysocka J. , Ryl J. , Sobaszek M. , Ossowski T. 
Published: October 2015

AbstractThis work describes the electrochemical method of boron‐doped diamond (BDD) modification by poly‐melamine to obtain organic films. The detection of adenine, guanine and caffeine was carried out by differential pulse wave voltammetry (DPV). The poly‐melamine modified B‐NCD electrodes exhibit excellent activity towards the electrochemical oxidation of all examined analytes. The poly‐melamine modified BDD electrodes in all measurements exhibit a larger peak current and are more sensitive compared to the unmodified BDD electrodes. The detection limit for adenine, guanine and caffeine using poly‐melamine modified BDD electrodes was found with 0.2 µM, 0.02 nM and 0.4 µM, respectively. Moreover, the double‐stranded (ctDNA), and single stranded DNA from calf thymus (ssDNA) was detected by DPV.
Out‐of‐plane seismic response of vertically spanning URM walls connected to flexible diaphragms
Authors: Derakhshan Hossein , Griffith Michael C. , Ingham Jason M. 
Published: October 2015

SummaryA simplified numerical model was used to investigate the out‐of‐plane seismic response of vertically spanning unreinforced masonry (URM) wall strips. The URM wall strips were assumed to span between two flexible diaphragms and to develop a horizontal crack above the wall mid‐height. Three degrees of freedom were used to accommodate the wall displacement at the crack height and at the diaphragm connections, and the wall dynamic stability was studied. The equations of dynamic motion were obtained using principles of rocking mechanics of rigid bodies, and the formulae were modified to include semi‐rigid wall behaviour. Parametric studies were conducted that included calculation of the wall response for different values of diaphragm stiffness, wall properties, applied overburden, wall geometry and earthquake ground motions. The results of the study suggest that stiffening the horizontal diaphragms of typical low‐rise URM buildings will amplify the out‐of‐plane acceleration demand imposed on the wall and especially on the wall–diaphragm connections. It was found that upper‐storey walls connected to two flexible diaphragms had reduced stability for applied earthquake accelerograms having dominant frequency content that was comparable with the frequency of the diaphragms. It was also found that the applied overburden reduced wall stability by reducing the allowable wall rotations. The results of this study suggest that the existing American Society of Civil Engineers recommendations for assessment of vertically spanning walls overestimate the stability of top‐storey walls in multi‐storey buildings in high‐seismic regions or for walls connected to larger period (less stiff) diaphragms. Copyright © 2015 John Wiley & Sons, Ltd.
Multivariate classification of smokers and nonsmokers using SVM‐RFE on structural MRI images
Authors: Ding Xiaoyu , Yang Yihong , Stein Elliot A. , Ross Thomas J. 
Published: October 2015

AbstractVoxel‐based morphometry (VBM) studies have revealed gray matter alterations in smokers, but this type of analysis has poor predictive value for individual cases, which limits its applicability in clinical diagnoses and treatment. A predictive model would essentially embody a complex biomarker that could be used to evaluate treatment efficacy. In this study, we applied VBM along with a multivariate classification method consisting of a support vector machine with recursive feature elimination to discriminate smokers from nonsmokers using their structural MRI data. Mean gray matter volumes in 1,024 cerebral cortical regions of interest created using a subparcellated version of the Automated Anatomical Labeling template were calculated from 60 smokers and 60 nonsmokers, and served as input features to the classification procedure. The classifier achieved the highest accuracy of 69.6% when taking the 139 highest ranked features via 10‐fold cross‐validation. Critically, these features were later validated on an independent testing set that consisted of 28 smokers and 28 nonsmokers, yielding a 64.04% accuracy level (binomial P = 0.01). Following classification, exploratory post hoc regression analyses were performed, which revealed that gray matter volumes in the putamen, hippocampus, prefrontal cortex, cingulate cortex, caudate, thalamus, pre‐/postcentral gyrus, precuneus, and the parahippocampal gyrus, were inversely related to smoking behavioral characteristics. These results not only indicate that smoking related gray matter alterations can provide predictive power for group membership, but also suggest that machine learning techniques can reveal underlying smoking‐related neurobiology. Hum Brain Mapp 36:4869–4879, 2015. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Acute and sub‐lethal exposure to copper oxide nanoparticles causes oxidative stress and teratogenicity in zebrafish embryos
Authors: Ganesan Santhanamari , Anaimalai Thirumurthi Naveenkumar , Raghunath Azhwar , Vijayakumar Savitha , Perumal Ekambaram 
Published: October 2015

AbstractNano‐copper oxides are a versatile inorganic material. As a result of their versatility, the immense applications and usage end up in the environment causing a concern for the lifespan of various beings. The ambiguities surround globally on the toxic effects of copper oxide nanoparticles (CuO‐NPs). Hence, the present study endeavored to study the sub‐lethal acute exposure effects on the developing zebrafish embryos. The 48 hpf LC50 value was about 64 ppm. Therefore, we have chosen the sub‐lethal dose of 40 and 60 ppm for the study. Accumulation of CuO‐NPs was evidenced from the SEM‐EDS and AAS analyzes. The alterations in the AChE and Na+/K+‐ATPase activities disrupted the development process. An increment in the levels of oxidants with a concomitant decrease in the antioxidant enzymes confirmed the induction of oxidative stress. Oxidative stress triggered apoptosis in the exposed embryos. Developmental anomalies were observed with CuO‐NPs exposure in addition to oxidative stress in the developing embryos. Decreased heart rate and hatching delay hindered the normal developmental processes. Our work has offered valuable data on the connection between oxidative stress and teratogenicity leading to lethality caused by CuO‐NPs. A further molecular mechanism unraveling the uncharted connection between oxidative stress and teratogenicity will aid in the safe use of CuO‐NPs. Copyright © 2015 John Wiley & Sons, Ltd.
On‐wafer characterization setup for model extraction and validation of high‐power GaN HEMT switches
Authors: Pirola M. , Camarchia V. , Quaglia R. , Ramella C. 
Published: October 2015

SummaryAn ad hoc setup for complete on‐chip large‐signal characterization of both series and parallel high‐power GaN high‐electron‐mobility transistor switches has been developed. Thanks to its characteristics, arbitrary loads at both switch terminals (i.e., drain and source) for power levels up to tens of watts can be applied. The setup is suitable for extraction and validation of equivalent circuit and behavioral models. The potentiality of the presented solution is demonstrated by model validation and measurements of series and shunt C‐band high‐power GaN high‐electron‐mobility transistor switches from two commercial foundries. Copyright © 2015 John Wiley & Sons, Ltd.
First olfactory fiber as an anatomical landmark for frontal sinus surgery
Authors: Upadhyay Smita , Buohliqah Lamia , Vieira Junior Gerival , Otto Bradley A. , Prevedello Daniel M. , Carrau Ricardo L. 
Published: October 2015

Objectives/HypothesisAccess to the frontal sinuses is technically challenging owing to their anterosuperior location, diverse anatomy, close proximity to critical structures and the need to work in a relatively narrow space with angled‐lens endoscopes and instruments. This study attempts to study the relationship of the first olfactory fiber with the frontal sinus posterior wall, assessing its fidelity as a surgical landmark during frontal sinus surgery.Study DesignAnatomic study.MethodsFifteen cadaveric specimens were studied. Measurements were obtained bilaterally using the data from individual CT scans. Median A‐P was defined as the anteroposterior (A‐P) diameter measured just lateral to the intersinus septum, paramedian A‐P was measured 5 mm lateral to the septum, and maximum A‐P was defined as the maximum anteroposterior diameter on axial images. A surgical navigation device was used to calculate the distance between the first olfactory fiber and the posterior table of the frontal sinus.ResultsThe mean distance between the first olfactory fiber and the posterior wall of the frontal sinus was (4.03 ± 2.7) mm on the right side and (4.2 ± 2.9) mm on the left. This distance strongly correlated with the maximum A‐P diameter of the sinus.ConclusionsIn a cadaveric model, the first olfactory fiber was found to be an average of 4.0 mm posterior to the frontal sinus. The significant variability of this distance should be considered when using the first olfactory fiber to establish the posterior boundary of a frontal sinusotomy. Drilling no further posterior than 7 mm rostral to the first olfactory fiber would be safe in 91% of patients.Level of EvidenceNA Laryngoscope, 126:1039–1045, 2016
Retrosigmoid versus translabyrinthine approach to acoustic neuroma resection: A comparative cost‐effectiveness analysis
Authors: Semaan Maroun T. , Wick Cameron C. , Kinder Kimberly J. , Stuyt John G. , Chota Rebecca L. , Megerian Cliff A. 
Published: October 2015

Objectives/HypothesisApproach‐specific economic data of acoustic neuroma (AN) resection is lacking. The purpose of this study was to analyze and compare adjusted total hospital costs, hospital and intensive care unit (ICU) length of stay (LOS), and associated factors in AN patients undergoing resection by translabyrinthine (TL) approach versus retrosigmoid (RS) approach.Study DesignRetrospective chart review.MethodsA total of 113 patients with AN undergoing TL (N = 43) or RS (N = 70) surgical resection between 1999 and 2012 were analyzed. Data including age, health status, preoperative hearing, tumor size, postoperative complications, hospital, ICU LOS, and disposition after discharge were collected from medical records and compared between both groups. Cost data was obtained from the hospital finance department and adjusted based on the Consumer Price Index for 2013.ResultsThere were no significant differences in demographic data, preoperative hearing, preoperative health status, or postoperative complication rate. Total hospital LOS and ICU LOS were significantly longer in the RS compared to the TL group (4.3 ± 3.6 vs. 2.6 ± 1.1 days; P < 0.001, and 1.5 ± 1.1 vs. 1.0 ± 0.5 days; P = 0.015, respectively). Tumors were larger in RS compared to the TL group (2.1 ± 1.0 cm vs. 1.5 ± 0.7 cm, respectively; P = 0.002). When patients were stratified by tumor size < or ≥ 2 cm, the total hospital LOS remained greater in the RS group in both subgroups (< and ≥ 2 cm, P < 0.001, and P = 0.031, respectively). However, there was no difference in the total ICU LOS between both subgroups. The adjusted mean total hospital cost was higher in the RS compared to the TL group ($25,069 ± 14,968 vs. $16,799 ± 5,724; P < 0.001). The adjusted mean total hospital cost was greater in the RS group with tumor < 2 cm (P < 0.001) but not significantly different in patients with tumors ≥ 2 cm. Univariate analysis showed that greater tumor size, poorer preoperative health status, the presence of major postoperative complications, and the RS approach were independently significantly associated with higher total hospital LOS (P = 0.001, P = 0.009, P = 0.001, and P < 0.001, respectively) and a higher adjusted total hospital cost (P < 0.001, P = 0.002, P = 0.014, and P < 0.001, respectively).ConclusionHospital LOS and total adjusted costs are significantly less for patients undergoing translabyrinthine acoustic neuroma resection compared to the retrosigmoid approach. Many factors appear to influence these differences. Economic considerations in addition to tumor characteristics and surgeon preference should be considered in future acoustic neuroma resections.Level of Evidence2c. Laryngoscope, 126:S5–S12, 2016
Correlation Between Physicomechanical and Swelling Properties of Weakly Basic Copolymer Hydrogels Based on (Meth)acrylate Polycations as New Smart Materials
Authors: Celik Tayyibe , Orakdogen Nermin 
Published: October 2015

2‐Hydroxyethyl methacrylate (HEMA) is incorporated to N,N‐dimethylaminoethyl methacrylate (DMAEMA) fabricating a series of stimuli‐responsive copolymer hydrogels by free radical copolymerization. The increasing comonomer content via adding more HEMA results in a higher network density and, therefore, a lower equilibrium swelling ratio. The uniaxial compressive testing results showed that increasing HEMA in the feed improved the mechanical strength of P(DMAEMA‐co‐HEMA) hydrogels. As HEMA increased, the elastic modulus as well as the effective crosslinked chain density increased. The work strives to provide method to tune mechanical and physical properties for weakly basic copolymer hydrogels based on (meth)acrylate polycations, which is hopefully to guide the design of hydrogels with desirable properties.
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Liquid Chromatography at Critical Conditions of Poly(propylene)
Authors: Bhati Sampat Singh , Macko Tibor , Brüll Robert , Mekap Dibyaranjan 
Published: October 2015

Liquid chromatography at critical conditions (LCCC) of poly(propylene) (PP) holds unique potential to further augment the understanding of molecular heterogeneities present in PP. The critical conditions for isotactic poly(propylene) (iPP) and syndiotactic poly(propylene) (sPP) have been identified using porous graphitic carbon as stationary phase and combinations of adsorption and desorption promoting solvents. It is found that 1,2,4‐trichlorobenzene is a stronger desorption promoting eluent compared to 1,2‐dichlorobenzene, while 2‐octanol shows a weaker adsorption promoting effect compared to 2‐ethyl‐1‐hexanol for all stereo‐isomeric forms of PP. The fraction of desorption promoting solvent needs to reach critical conditions decreased in a linear manner with the temperature. High temperature 2D liquid chromatography with infrared detection provides quantitative information about the fractions of the constituents (iPP and ethylene–propylene copolymer) of a model high impact PP sample at LCCC of iPP.
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A laminate‐based modelling approach for rate‐dependent switching in ferroelectric materials
Authors: Dusthakar Dinesh K , Menzel Andreas , Svendsen Bob 
Published: October 2015

AbstractThis contribution focuses on the sequential laminate‐based modelling approach for the numerical simulation of the complex electromechanical material behaviour of ferroelectric single crystals. The construction of engineered domain configurations by using the method of sequential lamination in order to study the domain evolution and polarisation switching in ferroelectric single crystals has recently been carried out in the works of [1–4]. By fulfilling the kinematic and polarisation compatibility conditions between the domain structures in a crystal, the proposed laminate‐based formulation is governed by an energy‐enthalpy function and by a dissipation potential. The mixed energy‐enthalpy, written in terms of the total strains, electric field and a set of internal variables, here the multi‐rank laminate volume fractions, governs the dissipative electromechanical response of the ferroelectric crystal, whereas the rate‐dependent dissipation potential formulated in terms of the flux of the internal variables describes the time‐dependent evolution of the multi‐rank laminate volume fractions, subjected to inequality constraints. The model reproduces experimentally observed hysteresis and butterfly curves, characteristic for single crystal ferroelectric materials, when subjected to homogeneous electromechanical loading conditions. (© 2015 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)