bluuebunny/crossref_metadata_2025_split huggingface dataset:
A robust approach to model densification and crack formation in powder compaction processes
Authors: Hernández J. A. , Oliver J. , Cante J. C. , Weyler R. 
Published: February 2011

AbstractThis paper deals with the question of how to efficiently integrate a constitutive model that describes the densification of powders and the potential formation of cracks in Powder Metallurgy (P/M) cold compaction processes. The analyzed model is a large strain, elastoplastic model of the Drucker–Prager/Cap type, refined to cover also the prediction of crack formation, and featuring non‐conventional elements such as a density‐dependent Von Mises yield surface; a parabolic plastic potential function for the Drucker–Prager envelope; and a softening law whose softening modulus is dependent on the level of densification. The employed integration procedure is a non‐conventional hybrid or IMPLicit–EXplicit (IMPL‐EX) scheme, whose essence is to solve explicitly for some variables and implicitly for others, with the peculiarity of the ‘explicit’ variables being but extrapolated values of the same quantities computed, at previous time steps, by means of a fully implicit scheme. The return‐mapping equations stemming from this implicit scheme are solved using an unconditionally convergent, fractional step method‐based iterative procedure. The performance of the IMPL‐EX integration algorithm is critically assessed in two different situations: the densification of a cylindrical specimen, and the fracture process in a diametral compression test. Results obtained show conclusively that the proposed hybrid integration strategy offers an efficient solution to the trade‐off between robustness and computational time requirements. Copyright © 2011 John Wiley & Sons, Ltd.
Was ist genau?
Authors: Gerhard Christoph , Wienecke Stephanie , Lotz Sandra 
Published: February 2011

AbstractDie Abbildungsqualität optischer Systeme hängt in hohem Maße von der Form‐ und Lagegenauigkeit der verwendeten optischen Komponenten ab. Bei der Konzeption, Fertigung und Montage solcher Abbildungssysteme stellen die Definition und Einhaltung geeigneter Toleranzen daher ausschlaggebende Faktoren dar. Dabei sind neben den Toleranzen zum Grundwerkstoff Glas besonders fertigungs‐ und montagetechnologische Toleranzen zu berücksichtigen.
Fasersensoren in der klassischen Messtechnik
Authors: Landmann Christoph , Jamal Rahman 
Published: February 2011

AbstractElektrische Sensoren erfassen physikalische oder chemische Effekte und wandeln diese in eine weiterverarbeitbare Größe um. Trotz ihres hohen Verbreitungsgrades sind diesen Sensoren, insbesondere aufgrund des verwendeten Übertragungsmediums, Grenzen gesetzt, die sich z. B. in Form von Übertragungsverlusten oder der Anfälligkeit gegenüber elektromagnetischen Störungen bemerkbar machen. Dadurch wird ihre Verwendung für viele Anwendungen in der Messtechnik stark eingeschränkt. Der Einsatz von optischen Sensoren auf Basis von Glasfasern stellt eine gute Alternative dar, da sie Licht anstelle von Strom und industrielle Glasfasern anstelle von herkömmlichen Kupferdrähten als Übertragungsmedium einsetzen. Dank der daraus resultierenden Vorteile haben sich Glasfasersensoren und zugehörige Messgeräte so weit entwickelt, dass sie in vielen Bereichen Anwendung finden.
Coating of structured catalytic reactors by plasma assisted polymerization of tetramethyldisiloxane
Authors: Essakhi Adil , Mutel Brigitte , Supiot Philippe , Löfberg Axel , Paul Sébastien , Courtois Véronique Le , Meille Valérie , Pitault Isabelle , Bordes‐Richard Elisabeth 
Published: February 2011

AbstractAn original process based on cold plasma assisted polymerization of tetramethyldisiloxane (TMDSO) in the presence of O2 was developed to cover substrates showing various shapes (plate and foam). In the frame of catalytic application, this coating has to act as a bonding layer for the deposition of active phase such as VOx/TiO2 well‐known for its properties in NOx and volatile organic compounds abatement and in the production of chemical intermediates. Good results were obtained by the deposition of a 5‐μm thick polysiloxane film followed by a thermal treatment under air at 650°C and by a remote nitrogen plasma post treatment. This procedure led to a silica‐like layer allowing its coating in an aqueous suspension of TiO2. Such a multilayered material can be obtained homogeneously on the whole surface of a sample showing a 3D open geometry like metallic foam. Characterizations of the different steps of the elaborated multilayer material were performed by Fourier transformed infrared spectroscopy, Raman spectrometry, X‐ray photoelectron spectroscopy, and electron probe micro‐analyzer. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Effects of carbon nanofibers on the fracture, mechanical, and thermal properties of PP/SEBS‐g‐MA blends
Authors: Liao Cheng Zhu , Tjong Sie Chin 
Published: February 2011

AbstractPolypropylene/maleated (styrene‐ethylene‐butadiene‐styrene) (PP/SEBS‐g‐MA) blends reinforced with 0.2–2.5 wt% carbon nanofibers (CNFs) were prepared by injection molding. The structure, thermal, mechanical, and fracture behaviors of PP/SEBS‐g‐MA blends and their nanocomposites were studied. Wide‐angle X‐ray diffraction (WAXD) results showed that the SEBS‐g‐MA and/or CNF additions do not induce a structural change of PP. Tensile measurements showed that the Young's modulus and tensile yield strength increase with the increasing filler content. Izod impact and essential work of fracture test results demonstrated that CNFs are beneficial to improve the impact strength and specific essential work of fracture of PP/SEBS‐g‐MA blends. Therefore, tough PP‐nanocomposites can be achieved by melt‐blending low fractions of CNFs and appropriate elastomer contents. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Ultrasonic and impulse welding of polylactic acid films
Authors: Vogel Julius , Grewell David , Kessler Michael R. , Drummer Dietmar , Menacher Markus 
Published: February 2011

AbstractThe weldability of polylactic acid (PLA) is examined in this article. Biaxially oriented PLA films of various thicknesses were joined with impulse and ultrasonic welding techniques. Relatively high weld strengths were achieved with impulse welding over a wide range of welding parameters. Ultrasonic welding produced high weld strengths with relatively short cycle times. In detail, ultrasonic welded samples had a weld factor (weld strength/base material strength) of 1 at cycle times of 0.25 sec. The weld factor was significantly lower at shorter weld times and weld times above 0.35 sec. In contrast, 100‐μm thick samples joined by impulse welding for 2–3 sec had a weld factor of 1 and a standard deviation of only ±5%. The peak temperature during the impulse welding was measured to determine the fusion temperatures of the films. Mechanical, thermal, and optical analysis was used to examine the properties of the PLA at various welding and annealing conditions. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Spatially separated atomic layer deposition of Al2O3, a new option for high‐throughput Si solar cell passivation
Authors: Vermang B. , Rothschild A. , Racz A. , John J. , Poortmans J. , Mertens R. , Poodt P. , Tiba V. , Roozeboom F. 
Published: February 2011

AbstractA next generation material for surface passivation of crystalline Si is Al2O3. It has been shown that both thermal and plasma‐assisted (PA) atomic layer deposition (ALD) Al2O3 provide an adequate level of surface passivation for both p‐ and n‐type Si substrates. However, conventional time‐resolved ALD is limited by its low deposition rate. Therefore, an experimental high‐deposition‐rate prototype ALD reactor based on the spatially separated ALD principle has been developed and Al2O3 deposition rates up to 1.2 nm/s have been demonstrated. In this work, the passivation quality and uniformity of the experimental spatially separated ALD Al2O3 films are evaluated and compared to conventional temporal ALD Al2O3, by use of quasi‐steady‐state photo‐conductance (QSSPC) and carrier density imaging (CDI). It is shown that spatially separated Al2O3 films of increasing thickness provide an increasing surface passivation level. Moreover, on p‐type CZ Si, 10 and 30 nm spatial ALD Al2O3 layers can achieve the same level of surface passivation as equivalent temporal ALD Al2O3 layers. In contrast, on n‐type FZ Si, spatially separated ALD Al2O3 samples generally do not reach the same optimal passivation quality as equivalent conventional temporal ALD Al2O3 samples. Nevertheless, after “firing”, 30 nm of spatially separated ALD Al2O3 on 250 µm thick n‐type (2.4 Ω cm) FZ Si wafers can lead to effective surface recombination velocities as low as 2.9 cm/s, compared to 1.9 cm/s in the case of 30 nm of temporal ALD Al2O3. Copyright © 2011 John Wiley & Sons, Ltd.
Reactivity of phenyl N‐phenylcarbamates in the alkaline hydrolysis reaction
Authors: Nalbantova Didi , Cheshmedzhieva Diana , Hadjieva Boriana , Ilieva Sonia , Galabov Boris 
Published: February 2011

AbstractIn the present study, we explore the application of several theoretically estimated indices that characterize the reactivity of a series of phenyl N‐phenylcarbamates in the alkaline hydrolysis reaction. The rate constants (at 25 °C) for the hydrolysis of several derivatives were spectrophotometrically determined. The obtained kinetic data in this study, combined with literature data for other derivatives, were then correlated with theoretically estimated reactivity indices: Hirshfeld and NBO atomic charges, the Parr electrophilicity index (ω), and the electrostatic potential at the carbon and oxygen atoms of the reaction centre (VC, VO). The predictive ability of these quantities is discussed in a comparative context. Copyright © 2011 John Wiley & Sons, Ltd.
Restricted sidechain plasticity in the structures of native proteins and complexes
Authors: Fleishman Sarel J. , Khare Sagar D. , Koga Nobuyasu , Baker David 
Published: February 2011

AbstractProtein‐design methodology can now generate models of protein structures and interfaces with computed energies in the range of those of naturally occurring structures. Comparison of the properties of native structures and complexes to isoenergetic design models can provide insight into the properties of the former that reflect selection pressure for factors beyond the energy of the native state. We report here that sidechains in native structures and interfaces are significantly more constrained than designed interfaces and structures with equal computed binding energy or stability, which may reflect selection against potentially deleterious non‐native interactions.
Association Among School‐related, Parental and Self‐related Problems and Morningness–Eveningness in Adolescents
Authors: Vollmer Christian , Schaal Steffen , Hummel Eberhard , Randler Christoph 
Published: February 2011

AbstractWe examined the relationship between morningness–eveningness and three dimensions of everyday stressors troubling adolescent pupils aged 13–16 years. Nine hundred and twenty‐four pupils in secondary education, grades 8 and 9, completed the Composite Scale of Morningness (covering habitual rise times and bedtimes) and three‐item sets of problem perception in adolescents, namely school‐related, parent‐related and self‐related problem perception. Bad school marks, eveningness orientation and type of school are associated with school‐related and parent‐related problems when controlling for age and gender. Girls reported more self‐related problems than boys. Given that school marks and chronotype were the most important moderators of problem perception, the results indicate that later school start times or adolescents changing their late bedtime behaviour, induced by an educational programme, could reduce the adolescents' stress perception and improve their academic performance. Copyright © 2011 John Wiley & Sons, Ltd.
Aryl hydrocarbon receptor‐independent up‐regulation of intracellular calcium concentration by environmental polycyclic aromatic hydrocarbons in human endothelial HMEC‐1 cells
Authors: Mayati Abdullah , Le Ferrec Eric , Lagadic‐Gossmann Dominique , Fardel Olivier 
Published: February 2011

AbstractPolycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene (B(a)P) constitute a major family of widely‐distributed environmental toxic contaminants, known as potent ligands of the aryl hydrocarbon receptor (AhR). B(a)P has been recently shown to trigger an early and transient increase of intracellular calcium concentration ([Ca2+]i), involved in AhR‐related up‐regulation of target genes by B(a)P. This study was designed to determine whether AhR may play a role in [Ca2+]i induction provoked by B(a)P. We demonstrated that, in addition to B(a)P, various PAHs, including pyrene and benzo(e)pyrene, known to not or only very poorly interact with AhR, similarly up‐regulated [Ca2+]i in human endothelial HMEC‐1 cells. Moreover, α‐naphthoflavone, a flavonoïd antagonist of AhR, was also able to induce [Ca2+]i. Knocking‐down AhR expression in HMEC‐1 cells through transfection of siRNAs, was finally demonstrated to not prevent B(a)P‐mediated induction of [Ca2+]i, whereas it efficiently counteracted B(a)P‐mediated induction of the referent AhR target gene cytochrome P‐450 1B1. Taken together, these data demonstrate that environmental PAHs trigger [Ca2+]i induction in an AhR‐independent manner. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2012.
Steady flow along a Rankine half‐body
Authors: Crane L.J. , McVeigh A.G. 
Published: February 2011

AbstractThis paper deals with the net frictional drag on a Rankine half‐body in uniform axisymmetric flow. Asymptotic series solutions for the non‐dimensional drag coefficient are developed for flow close to the forward stagnation point and downstream, while for the intermediate region, the solution is obtained by employing interpolating polynomials. Consideration is given to flows having Reynolds number of 100 and 1000. The results are compared to those for a slender uniform cylinder obtained by Seban and Bond [1], Glauert and Lighthill [2], and Curle [3].
Limited value of positron emission tomography in treatment of pancreatic cancer: Surgeon’s view
Authors: Kasperk Reinhard K. , Riesener Klaus‐Peter , Wilms Kirsten , Schumpelick Volker 
Published: February 2011

AbstractWe aimed to assess, from a surgical point of view, the value of positron emission tomography (PET) in the routine preoperative diagnostic evaluation of a pancreatic mass. In particular, we were interested in PET’s ability to distinguish a malignancy from a nonmalignant process and its impact on surgical decision making. We documented prospectively the results of preoperative ultrasonography, computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP), and PET in terms of a correct diagnosis of malignancy in 103 patients. All patients underwent surgery at our department and had a complete histologic workup. We then related the preoperative findings to the intraoperative and histologic findings and analyzed the advantages and limitations of PET in comparison with conventional diagnostic techniques. Both CT and PET showed high sensitivities (82% and 84%, respectively) but rather low specificities (61%). ERCP showed good specificity at 83% but weak sensitivity at 46%. The positive predictive value was higher than 80% for all methods, whereas the negative predictive value was around 60% at best. Both the CT and the PET diagnoses were wrong in 15% of the cases. In all cases with a false CT diagnosis, the results of the other conventional examinations provided sufficient evidence to indicate the need for surgical intervention. In all cases where PET gave misleading results, CT findings indicated the need for surgery. PET overlooked pT1 cancers in three of the patients. PET does not reliably prove or exclude malignancy in situations where conventional diagnostic procedures leave doubt as to the nature of a pancreatic mass. PET does introduce a new procedure‐related spectrum of misinterpretations to the diagnostic process.
Oxidative Stability of Cashew Oils from Raw and Roasted Nuts
Authors: Chandrasekara Neel , Shahidi Fereidoon 
Published: February 2011

AbstractCashew nut oils, extracted from raw and roasted whole cashew nuts, were examined for their fatty acid composition, color change and oxidative stability. Fatty acids were analyzed using gas chromatography, and a spectrophotometric method was used to determine the color changes of the resultant oils. Oxidative stability was determined under accelerated oxidation conditions by employing conjugated diene (CD) and thiobarbituric acid reactive substances (TBARS) assays. The contents of monounsaturated (MUFA), polyunsaturated (PUFA) and saturated (SAFA) fatty acids were 61, 17 and 21%, respectively. Oleic acid was the major MUFA whereas linoleic acid was the main PUFA present in cashew nut oils. Oxidative stability of the oil as determined by CD values after 72 h of storage under Schall oven condition at 60 °C was 1.08 and 0.65 for the raw and high temperature roasted cashew nut, respectively. The TBARS values, expressed as malondialdehyde equivalents decreased with increasing roasting temperature. Thus roasting of whole cashew nuts improved the oxidative stability of the resultant nut oils.
Horses and Zebras: complex cardiac anatomy in a patient with out-of-hospital cardiac arrest
Authors: Brown Samuel M. , Miller Dylan V. , Vezina Daniel , Dean Nathan C. , Grissom Colin K. 
Published: February 2011

Abstract
This case report describes a woman presenting after out-of-hospital cardiac arrest with several cardiac anomalies, including a form fruste of Ebstein's anomaly complicated by a large tricuspid valve vegetation. On autopsy, she proved to have unstable plaques in epicardial vessels that likely caused arrhythmic sudden cardiac death, a reminder that even in the presence of rare anomalies, common things are common.
Emergency department diagnosis of atrial and ventricular septal defects, bicuspid aortic valve and pulmonary hypertension
Authors: Riley David C. , Kim Inho , Sacco Dana , Rosen Tony 
Published: February 2011

Abstract

Introduction
A 41-year-old Cuban man with Down syndrome and mental retardation was brought to the Emergency Department for episodes of worsening shortness of breath over one day. Bedside color Doppler ultrasound subcostal and apical four-chamber examination of the heart revealed atrial and ventricular septal defects with left-to-right shunting of blood. A right ventricular outflow tract view revealed a bicuspid aortic valve, and continuous wave Doppler ultrasound in the right ventricular inflow tract view revealed tricuspid regurgitation and pulmonary hypertension.

Conclusion
Bedside echocardiography with color Doppler and continuous wave Doppler imaging can assist the emergency physician and the critical care physician in the diagnosis of ASD, VSD, bicuspid aortic valve, and pulmonary hypertension in the Down syndrome patient who is short of breath.
Diagnosis of traumatic iliopsoas hematoma using point-of-care ultrasound
Authors: Kameda Toru , Fujita Masato , Takahashi Isao 
Published: February 2011

Abstract
Case 1 involved a 24-year-old man who complained of severe right groin pain and difficulty of walking after falling to the ground while snowboarding. The patient manifested flexion hip contracture on the right side. Abdominal examination detected tenderness in the right lower quadrant. Point-of-care ultrasound identified swelling of the right psoas major, compressing the right kidney. Case 2 involved a 74-year-old woman who complained of severe left lower quadrant and left groin pain after falling down. This patient also manifested flexion hip contracture, on the left side. Abdominal examination detected tenderness mainly in the left lower quadrant and a palpable mass accompanied by tenderness, lateral to the left femoral artery. Point-of-care ultrasound identified swelling of the left psoas major and of the iliopsoas musculotendinous unit at the level of the groin. Point-of-care ultrasound after obtaining precise history and the physical examination is a very useful modality for the quick diagnosis of iliopsoas hematoma in the emergency rooms.
Sirtuin 1 in skeletal muscle of cachectic tumour‐bearing rats: a role in impaired regeneration?
Authors: Toledo Míriam , Busquets Sílvia , Ametller Elisabet , López-Soriano Francisco J. , Argilés Josep M. 
Published: February 2011

BackgroundIn advanced malignant disease, cachexia and muscle wasting appear to be among the most common manifestations. This phenomenon is partially related with a decreased muscle regeneration capacity, as previously described in our laboratory.Methods and resultsRats bearing the Yoshida AH‐130 ascites hepatoma were used in the experiments. The animals experienced a marked weight loss with decreases in skeletal muscle weights (13% gastrocnemius, 18% extensor digitorum longus, and 12% tibialis muscles). Muscle gene expression was measured using real‐time polymerase chain reaction. Skeletal muscle from cachectic tumour‐bearing rats is associated with a decreased expression of genes involved in regeneration such as Pax‐7 (39%), myogenin (24%), and MyoD (17%). mRNA levels of Sirt1 increased (91%) in cachectic skeletal muscle. The Sirt1 gene has been shown to be associated with changes in muscle myoblast differentiation. Treatment of the tumour‐bearing animals with formoterol—a beta2‐agonist—normalizes the expression of genes involved in regeneration (i.e., increase of Pax7 (139%)), at the same time as it does with that of Sirt1 (42% decrease).ConclusionsIt is suggested that the lack of muscle regeneration observed during muscle wasting in tumour‐bearing animals is linked to the action of Sirt‐1, possibly via PGC‐1α. These factors may constitute possible targets of pharmacological treatment against muscle loss, thus potentially contributing to the understanding and mitigation of muscle atrophy associated with disease.
FIGO classification system (PALM‐COEIN) for causes of abnormal uterine bleeding in nongravid women of reproductive age
Authors: Munro Malcolm G. , Critchley Hilary O.D. , Broder Michael S. , Fraser Ian S. ,   for the FIGO Working Group on Menstrual Disorders
Published: February 2011

AbstractThere is general inconsistency in the nomenclature used to describe abnormal uterine bleeding (AUB), in addition to a plethora of potential causes—several of which may coexist in a given individual. It seems clear that the development of consistent and universally accepted nomenclature is a step toward rectifying this unsatisfactory circumstance. Another requirement is the development of a classification system, on several levels, for the causes of AUB, which can be used by clinicians, investigators, and even patients to facilitate communication, clinical care, and research. This manuscript describes an ongoing process designed to achieve these goals, and presents for consideration the PALM‐COEIN (polyp; adenomyosis; leiomyoma; malignancy and hyperplasia; coagulopathy; ovulatory dysfunction; endometrial; iatrogenic; and not yet classified) classification system for AUB, which has been approved by the International Federation of Gynecology and Obstetrics (FIGO) Executive Board as a FIGO classification system.