bluuebunny/crossref_metadata_2025_split huggingface dataset:
Visualizing Strain Evolution and Coordinated Buckling within CNT Arrays by In Situ Digital Image Correlation
Authors: Maschmann Matthew R. , Ehlert Gregory J. , Park Sei Jin , Mollenhauer David , Maruyama Benji , Hart A. John , Baur Jeffery W. 
Published: July 2012

AbstractSpatial mapping of strain fields within compressed carbon nanotube (CNT) array columns is achieved using digital image correlation (DIC) analysis of in situ scanning electron microscopy (SEM) image sequences. Full‐field displacement and strain maps are generated based upon the motion of the constituent CNTs, which serve as a traceable high‐contrast speckle pattern for DIC analysis. The deformation modes and CNT array buckling characteristics vary systematically as a function of column aspect ratio, including bending, crushing, and bottom‐up buckle accumulation behaviors. In spite of disparate appearing deformation modes, strain maps indicate that CNT array buckling consistently initiates at 5% local principal strain (ϵ2) for all columns. The ability to quantitatively assess the deformation modes and buckling behavior of CNT arrays at the nanoscale will enable their improved design for high‐strain electrical contacts, compliant thermal interfaces, force sensors, energy‐absorbing foams, or other applications.
Prenatal Alcohol Exposure Affects Vasculature Development in the Neonatal Brain
Authors: Jégou Sylvie , El Ghazi Faiza , de Lendeu Pamela Kwetieu , Marret Stéphane , Laudenbach Vincent , Uguen Arnaud , Marcorelles Pascale , Roy Vincent , Laquerrière Annie , Gonzalez Bruno José 
Published: July 2012

AbstractObjective:In humans, antenatal alcohol exposure elicits various developmental disorders, in particular in the brain. Numerous studies focus on the deleterious effects of alcohol on neural cells. Although recent studies suggest that alcohol can affect angiogenesis in adults, the impact of prenatal alcohol exposure on brain microvasculature remains poorly understood.Methods:We used a mouse model to investigate effects of prenatal alcohol exposure on the cortical microvascular network in vivo and ex vivo and the action of alcohol, glutamate, and vascular endothelial growth factor A (VEGF) on activity, plasticity, and survival of microvessels. We used quantitative reverse transcriptase polymerase chain reaction, Western blot, immunohistochemistry, calcimetry, and videomicroscopy. We characterized the effect of prenatal alcohol exposure on the cortical microvascular network in human controls and fetal alcohol syndrome (FAS)/partial FAS (pFAS) patients at different developmental stages.Results:In mice, prenatal alcohol exposure induced a reduction of cortical vascular density, loss of the radial orientation of microvessels, and altered expression of VEGF receptors. Time‐lapse experiments performed on brain slices revealed that ethanol inhibited glutamate‐induced calcium mobilization in endothelial cells, affected plasticity, and promoted death of microvessels. These effects were prevented by VEGF. In humans, we evidenced a stage‐dependent alteration of the vascular network in the cortices of fetuses with pFAS/FAS. Whereas no modification was observed from gestational week 20 (WG20) to WG22, the radial organization of cortical microvessels was clearly altered in pFAS/FAS patients from WG30 to WG38.Interpretation:Prenatal alcohol exposure affects cortical angiogenesis both in mice and in pFAS/FAS patients, suggesting that vascular defects contribute to alcohol‐induced brain abnormalities. Ann Neurol ANN NEUROL 2012;72:952–960
A New Observer‐Type Consensus Protocol for Linear Multi‐Agent Dynamical Systems
Authors: Zhao Yu , Wen Guanghui , Duan Zhisheng , Xu Xiang , Chen Guanrong 
Published: July 2012

AbstractThe consensus problem is investigated in this paper for a class of multi‐agent systems with general linear node dynamics and directed communication topologies. A new distributed observer‐type consensus protocol is designed based only on the relative output measurements of neighboring agents. Compared with existing observer‐type protocols, the one presented here does not require information about the relative states of the observers. Tools from small gain theory and matrix analysis, some sufficient conditions are obtained for achieving consensus in such multi‐agent systems where the underlying network topology contains a directed spanning tree. Finally, some numerical examples including an application in low‐Earth‐orbit satellite formation flying are provided to illustrate the theoretical results.
Problem‐solving test: The role of ubiquitination in epidermal growth factor receptor trafficking
Authors: Szeberényi József 
Published: July 2012

AbstractTerms to be familiar with before you start to solve the test: growth factor signaling, epidermal growth factor, tyrosine protein kinase, tyrosine phosphorylation, ubiquitin, monoubiquitination, polyubiquitination, site‐directed mutagenesis, transfection, expression vector, cDNA, immunoprecipitation, SDS‐polyacrylamide gel electrophoresis, Western blotting, radioactive labeling, receptor‐mediated endocytosis.
Inhibition of Lipopolysaccharide Transport to the Outer Membrane in Pseudomonas aeruginosa by Peptidomimetic Antibiotics
Authors: Werneburg Martina , Zerbe Katja , Juhas Mario , Bigler Laurent , Stalder Urs , Kaech Andres , Ziegler Urs , Obrecht Daniel , Eberl Leo , Robinson John A. 
Published: July 2012

AbstractThe asymmetric outer membrane (OM) of Gram‐negative bacteria contains lipopolysaccharide (LPS) in the outer leaflet and phospholipid in the inner leaflet. During OM biogenesis, LPS is transported from the periplasm into the outer leaflet by a complex comprising the OM proteins LptD and LptE. Recently, a new family of macrocyclic peptidomimetic antibiotics that interact with LptD of the opportunistic human pathogen Pseudomonas aeruginosa was discovered. Here we provide evidence that the peptidomimetics inhibit the LPS transport function of LptD. One approach to monitor LPS transport involved studies of lipid A modifications. Some modifications occur only in the inner membrane while others occur only in the OM, and thus provide markers for LPS transport within the bacterial envelope. We prepared a conditional lptD mutant of P. aeruginosa PAO1 that allowed control of lptD expression from the rhamnose promoter. With this mutant, the effects caused by the antibiotic on the wild‐type strain were compared with those caused by depleting LptD in the mutant strain. When LptD was depleted in the mutant, electron microscopy revealed accumulation of membrane‐like material within cells and OM blebbing; this mirrored similar effects in the wild‐type strain caused by the antibiotic. Moreover, the bacterium responded to the antibiotic, and to depletion of LptD, by introducing the same lipid A modifications, consistent with inhibition by the antibiotic of LptD‐mediated LPS transport. This conclusion was further supported by monitoring the radiolabelling of LPS from [14C]acetate, and by fractionation of IM and OM components. Overall, the results provide support for a mechanism of action for the peptidomimetic antibiotics that involves inhibition of LPS transport to the cell surface.
Repeat balloon aortic valvuloplasty effectively delays surgical intervention in children with recurrent aortic stenosis
Authors: Petit Christopher J. , Maskatia Shiraz A. , Justino Henri , Mattamal Raphael J. , Crystal Matthew A. , Ing Frank F. 
Published: July 2012

ObjectiveBalloon aortic valvuloplasty (BAV) is the primary therapy for congenital aortic stenosis (AS). Recurrent AS following initial BAV or initial surgical valvotomy (SV) may require a second BAV (BAV2). We sought to determine the longterm outcomes of BAV2.DesignWe reviewed all cases of BAV2, defined as BAV following primary BAV or SV between 1988 and 2009. Cases were reviewed for pre‐ and post‐BAV2 echocardiographic and procedural details.SettingTertiary care dedicated children's hospital.PatientsBetween 1985 and 2009, 43 patients underwent BAV2 (23 primary SV, 20 primary BAV) at median age 1.9 years (1 month–21 years) and median weight 15 (3.3–55) kg.InterventionsBAV2 performed following primary SV or primary BAV. Main OutcomeMeasuresWe evaluated the following endpoints: ≥ moderate AI post‐BAV2, aortic valve replacement (AVR), additional BAV or SV post‐BAV2, death and heart transplantation.ResultsThe gradient decreased from 61.4 ± 16.0 mm Hg to 26.0 ± 13.6 post‐BAV2 (P < 0.01). Gradient prior to BAV2 was higher in primary SV patients (66 ± 13 mm Hg) than in primary BAV patients (56 ± 18 mm Hg, P = 0.04). 24 patients had no further events after BAV2, while 19 patients (44%) experienced 23 events including: AVR (n = 8), SV (n = 6), BAV3 (n = 2), death (n = 5), and transplant (n = 1). Regression demonstrated that adverse events were associated with higher post‐BAV2 gradient (P < 0.01). Repeat intervention on the aortic valve and AVR were associated with higher post BAV2 gradient (P = 0.04, P = 0.01). Prior to BAV2, 7 patients (17%) had AI > mild, compared to 21 (51%) patients after BAV2. Cox regression revealed that primary BAV was associated with development of AI > mild after BAV2 (P < 0.01).ConclusionBAV2 is associated with decreased valve gradient, though with an increase in AI. However, residual AS, not AI, is associated with poor outcomes following BAV2. BAV2 effectively treats recurrent AS and postpones need for surgical intervention. © 2013 Wiley Periodicals, Inc.
An Efficient Way for the Recognition of Zinc Ion via the Fluorescence Enhancement
Authors: Sang Qiuguang , Yang Jingkui 
Published: July 2012

AbstractThis study concentrates on the spectral and complexing properties of a tetraoxycalix[2]arene[2]triazine derivative bearing two bipyridines (Calix‐BIPY2) in a mixture of acetonitrile:chloroform (4:1, V:V). The results show that Calix‐BIPY2 has a highly selectivity and sensitivity towards Zn2+ over various competing cations (K+, Cu2+, Cd2+, Co2+, Fe2+, Hg2+, Ag+, Al3+ and Pb2+). The complexation of Zn2+ induces a remarkable fluorescence enhancement due to combination effects of the binding strength, electron spins state of metal ions, photoinduced charge transfer (PCT) and the rigidity of the complexing unit offered by calixarene‐based hosts.
Effect of Vacancy Defects on the Young's Modulus and Fracture Strength of Graphene: A Molecular Dynamics Study
Authors: Zhu Jian , He Ming , Qiu Feng 
Published: July 2012

AbstractThe Young's modulus of graphene with various rectangular and circular vacancy defects is investigated by molecular dynamics simulation. By comparing with the results calculated from an effective spring model, it is demonstrated that the Young's modulus of graphene is largely correlated to the size of vacancy defects perpendicular to the stretching direction. And a linear reduction of Young's modulus with the increasing concentration of mono‐atomic‐vacancy defects (i.e., the slope of −0.03) is also observed. The fracture behavior of graphene, including the fracture strength, crack initiation and propagation are then studied by the molecular dynamics simulation, the effective spring model, and the quantized fracture mechanics. The blunting effect of vacancy edges is demonstrated, and the characterized crack tip radius of 4.44 Å is observed.
Postnatal expression of TrkB receptor in rat vestibular nuclear neurons responsive to horizontal and vertical linear accelerations
Authors: Ma Chun‐Wai , Zhang Fu‐Xing , Lai Chun‐Hong , Lai Suk‐King , Yung Ken Kin‐Lam , Shum Daisy Kwok‐Yan , Chan Ying‐Shing 
Published: July 2012

AbstractWe examined the maturation expression profile of tyrosine kinase B (TrkB) receptor in rat vestibular nuclear neurons that were activated by sinusoidal linear acceleration along the horizontal or vertical axis. The otolithic origin of Fos expression in these neurons was confirmed with labyrinthectomized controls and normal controls, which showed only sporadically scattered Fos‐labeled neurons in the vestibular nucleus. In P4–6 test rats, no Fos‐labeled neurons were found in the vestibular nucleus, but the medial and spinal vestibular neurons showed weak immunoreactivity for TrkB. The intensity of TrkB immunoreactivity in vestibular nuclear neurons progressively increased in the second postnatal week but remained low in adults. From P7 onward, TrkB‐expressing neurons responded to horizontal or vertical otolithic stimulation with Fos expression. The number of Fos‐labeled vestibular nuclear neurons expressing TrkB increased with age, from 13–43% in P7 rats to 85–90% in adult rats. Our results therefore suggest that TrkB/neurotrophin signaling plays a dominant role in modulating vestibular nuclear neurons for the coding of gravity‐related horizontal head movements and for the regulation of vestibular‐related behavior during postnatal development. J. Comp. Neurol. 521:612–625, 2013. © 2012 Wiley Periodicals, Inc.
BaSi4O6N2 – A Hexacelsian‐Type Layered Oxonitridosilicate
Authors: Braun Cordula , Ehrenberg Helmut , Schnick Wolfgang 
Published: July 2012

AbstractWith BaSi4O6N2 it was possible to synthesize a new compound in the hexacelsian structure type that has not been observed for nitrido‐ or oxonitridosilicates before. BaSi4O6N2 was obtained by employing the multi‐anvil technique at pressures of 12–15 GPa and temperatures between 900 and 1200 °C starting from BaSi2O2N2. The crystal structure of BaSi4O6N2 was solved on the basis of X‐ray powder diffraction data [P6/mmm, no. 191, a = 5.3512(2) Å, c = 7.5235(4) Å, V = 186.57 Å3, Z = 1, Rwp = 0.065] and was refined by the Rietveld method employing difference Fourier analyses. BaSi4O6N2 represents a nonbranched double‐layer silicate with a high degree of condensation [κ = 0.5, i.e. the atomic ratio n(Si)/n(O,N)]. The layers of BaSi4O6N2 are made up of vertex‐sharing SiO3N tetrahedra forming hexagonal double layers that exhibit Sechser‐rings as fundamental building units (FBU). Unlike most known nitrido‐ and oxonitridosilicates, no N[3] but only double bridging N[2] atoms are found in the silicate substructure. All of the oxygen atoms (O[2]) bridge two Si atoms as well. Along [001] the Ba2+ ions are located in the Sechser‐ring channels. The cations are coordinated by twelve O and six N atoms and are situated between and within the double layers. In‐situ high‐temperature investigations at low pressure with synchrotron radiation indicated that decomposition reactions occurred. Attempts to dope BaSi4O6N2 with Eu2+ are described; however, no luminescence was observed.
Reactivity of the Malonaldehyde‐Glyoxal and Malonaldehyde‐Methylglyoxal Adducts of Adenine Nucleosides toward Amino Acid Cross‐Link Formation
Authors: Pluskota‐Karwatka Donata , Matysiak Dorota , Makarewicz Marta , Kronberg Leif 
Published: July 2012

AbstractDNA–protein cross‐links are formed upon exposure to a variety of physical and exogenous, as well as endogenous chemical agents. This type of damage poses a threat to genomic integrity. Among the agents capable of inducing DNA–protein cross‐links bifunctional electrophiles arising from cellular processes deserve particular attention. Representatives of such electrophiles include glyoxal, methylglyoxal and malonaldehyde. Herein, we report that glyoxal and methylglyoxal adducts of 2′‐deoxyadenosine formed in the presence of malonaldehyde {M1Gx‐dA [8‐(diformylmethyl)‐3‐(2′‐deoxy‐β‐D‐ribofuranosyl)imidazo[2,1‐i]purine], and M1MGx‐dA [8‐(diformylmethyl)‐7‐methyl‐3‐(2′‐deoxy‐β‐D‐ribofuranosyl)imidazo[2,1‐i]purine], respectively}, display high reactivity towards lysine derivatives. In reactions with Nα‐acetyllysine M1Gx‐dA was found to form three adducts whereas M1MGx‐dA reacted with the lysine congener to form two stable products. All compounds were isolated and their structures determined on the basis of 2D NMR spectroscopy. Formation of the analogous products was shown in the individual reactions of M1Gx‐dA and M1MGx‐dA with Nϵ‐acetyllysine. Mechanisms proposed for formation of all characterised compounds are also discussed. This study reports identification of structures for a potentially new class of DNA–protein cross‐links.
Personality Subtypes in Female Pre‐Bariatric Obese Patients: Do They Differ in Eating Disorder Symptoms, Psychological Complaints and Coping Behaviour?
Authors: Claes Laurence , Vandereycken Walter , Vandeputte An , Braet Caroline 
Published: July 2012

AbstractIn the pre‐bariatric psychological assessment of 102 morbidly obese women, two personality subtypes emerged: a resilient/high functioning subtype with a ‘normal’ personality profile and an emotional dysregulated/undercontrolled subtype, characterized by high neuroticism and low extraversion/conscientiousness. Emotional dysregulated/undercontrolled patients showed more concerns about eating/weight/shape, more binge eating driven by emotions and external triggers, more psychological complaints (such as depression and anxiety) and more avoidance and depressive coping reactions than resilient/high functioning patients. Further research should clarify whether these clearly different psychological profiles are related to different outcomes (weight loss or well‐being) of bariatric surgery. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
Clinical and Temperamental Correlates of Body Image Disturbance in Eating Disorders
Authors: Zanetti Tatiana , Santonastaso Paolo , Sgaravatti Eleonora , Degortes Daniela , Favaro Angela 
Published: July 2012

AbstractObjectiveAlthough body image disturbance (BID) is considered a core symptom in anorexia nervosa (AN) and bulimia nervosa (BN), little is known about its psychopathological correlates. The present study aimed at analysing the correlation of aspects of BID with psychopathological and temperamental characteristics.MethodA sample of 1288 patients (538 AN and 750 BN) were assessed through a structured diagnostic interview, the Eating Disorders Inventory and Tridimensional Personality Questionnaire. Cognition of body image distortion, weight checking, fear of weight gain and body dissatisfaction were assessed by specific questions during the interview.ResultsVarious aspects of BID formed similar, but not identical, dimensions in AN and BN. In both groups, anticipatory anxiety and interoceptive awareness were significantly and independently associated with body image distortion, whereas ineffectiveness was associated with weight checking.DiscussionBody image disturbance is a multidimensional characteristic linked to psychological features, such as anticipatory anxiety, ineffectiveness and interoceptive awareness. These findings have scientific and treatment implications, and should be considered by clinicians in adopting successful treatment strategies. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
HOW WELL DO DIAGNOSIS‐RELATED GROUP SYSTEMS GROUP BREAST CANCER SURGERY PATIENTS?—EVIDENCE FROM 10 EUROPEAN COUNTRIES
Authors: Scheller‐Kreinsen David ,   on behalf of the EuroDRG group
Published: July 2012

ABSTRACTWe analysed patient‐level data (n = 72 235) from 563 hospitals in 10 European countries to assess the ability of national diagnosis‐related group (DRG) systems to account for patient‐level variation in cost or lengths of stay of breast cancer surgery patients against a standard set of patient characteristics, treatment and quality variables. We find that European DRG systems use very different types of classification variables and numbers of DRGs (range: 3–7) to classify these patients. In 6 of 10 countries, the set of patient characteristics, treatment and quality variables, which we were able to define across countries, perform better than the set of national DRGs in accounting for patient‐level variation in resource consumption. Moreover, there appear to be factors that are consistently significant determinants of cost/length of stay of breast cancer surgery cases but are not, or at least not fully, considered in European DRG systems. Our results therefore raise concerns as to whether all systems rely on the most appropriate classification variables. In several countries, policymakers should reevaluate the appropriateness of their DRG algorithm for breast cancer surgery and of specific DRG weights. Copyright © 2012 John Wiley & Sons, Ltd.
DRGs IN EUROPE: A CROSS COUNTRY ANALYSIS FOR CHOLECYSTECTOMY
Authors: Paat‐Ahi Gerli , Świderek Maria , Sakowski Paweł , Saluse Janek , Aaviksoo Ain ,   on behalf of the EURODRG group
Published: July 2012

ABSTRACTCholecystectomy is the surgical removal of the gallbladder. It is the most common method for treating symptomatic gallstones. Despite the existence of well‐established treatment guidelines, the rate of cholecystectomy varies widely across Europe. We analyse patients in 10 countries that had undergone surgery for the treatment of symptomatic gallstones. We test the performance of three models in explaining variation in the (log of) cost of the inpatient stay (seven countries) or length of stay (three countries). The first model includes only the diagnosis‐related group (DRG) variables to which cholecystectomy patients were coded (MD), the second uses a core set of patient characteristics and episode‐specific explanatory variables (MP), and finally, the third model combines both sets of variables (MF). Countries vary both in the number of DRGs used to classify cholecystectomy patients (range: 2–8), and in the percentage of patients covered by a single DRG (range: 50%–92%). The ability of combining both DRGs and patient level variables to explain cost variation among patients ranges from 58% in Spain to over 81% in Finland. The comparison of models' performance suggests that incorporating relevant patient characteristics may significantly improve DRG systems. Copyright © 2012 John Wiley & Sons, Ltd.
Development and comparative assessment of Raman spectroscopic classification algorithms for lesion discrimination in stereotactic breast biopsies with microcalcifications
Authors: Dingari Narahara Chari , Barman Ishan , Saha Anushree , McGee Sasha , Galindo Luis H. , Liu Wendy , Plecha Donna , Klein Nina , Dasari Ramachandra Rao , Fitzmaurice Maryann 
Published: July 2012

AbstractMicrocalcifications are an early mammographic sign of breast cancer and a target for stereotactic breast needle biopsy. Here, we develop and compare different approaches for developing Raman classification algorithms to diagnose invasive and in situ breast cancer, fibrocystic change and fibroadenoma that can be associated with microcalcifications. In this study, Raman spectra were acquired from tissue cores obtained from fresh breast biopsies and analyzed using a constituent‐based breast model. Diagnostic algorithms based on the breast model fit coefficients were devised using logistic regression, C4.5 decision tree classification, k‐nearest neighbor (k ‐NN) and support vector machine (SVM) analysis, and subjected to leave‐one‐out cross validation. The best performing algorithm was based on SVM analysis (with radial basis function), which yielded a positive predictive value of 100% and negative predictive value of 96% for cancer diagnosis. Importantly, these results demonstrate that Raman spectroscopy provides adequate diagnostic information for lesion discrimination even in the presence of microcalcifications, which to the best of our knowledge has not been previously reported. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)