bluuebunny/crossref_metadata_2025 huggingface dataset:
Thyroid hormone and the stunned myocardium
Authors: Novitzky Dimitri , Cooper David K C
Published: August 2014

Acute critically ill patients experience a rapid decline in plasma free thyroid hormone levels (free triiodothyronine (FT3) and free levothyroxine (FT4)), with a marked elevation of reverse T3, recognized as the euthyroid sick syndrome (ESS) or low-T3syndrome. The ESS is also often associated with depressed myocardial function, sometimes referred to as the ‘stunned myocardium’. Its clinical effects may vary from minimal hemodynamic impairment to cardiogenic shock. Medical management may range from aspirin alone to placement of a left ventricular assist device. With adequate supportive therapy, recovery usually occurs within days or weeks. The effect of T3/T4therapy has been studied in three conditions in which the ESS and myocardial functional depression have been documented – i) transient regional myocardial ischemia and reperfusion, ii) transient global myocardial ischemia in patients undergoing cardiac surgery on cardiopulmonary bypass, and iii) transient inadequate global myocardial perfusion in brain-dead potential organ donors. Under all three conditions, myocardial ischemia leads to rapid loss of high-energy phosphates, accumulation of myocardial tissue lactate, and probably loss of homeostasis of cytosolic calcium, which may further increase cell injury. There is an inability to generate ATP through the Krebs cycle, which reduces the high-energy phosphate pool essential for all cell ATPases. Under all three conditions, following administration of T3/T4, the myocardial dysfunction was rapidly reversed. We, therefore, cautiously advocate the use of thyroid hormonal therapy to any patient with the ESS and/or a stunned myocardium.
Expression, activation, and role of AKT isoforms in the uterus
Authors: Fabi François , Asselin Eric
Published: August 2014

The three isoforms of AKT: AKT1, AKT2, and AKT3, are crucial regulators of both normal and pathological cellular processes. Each of these isoforms exhibits a high level of homology and functional redundancy with each other. However, while being highly similar and structurally homologous, a rising amount of evidence is showing that each isoform possesses specific targets as well as preferential subcellular localization. The role of AKT has been studied extensively in reproductive processes, but isoform-specific roles are yet to be fully understood. This review will focus on the role of AKT in the uterus and its function in processes related to cell death and proliferation such as embryo implantation, decidualization, endometriosis, and endometrial cancer in an isoform-centric manner. In this review, we will cover the activation of AKT in various settings, localization of isoforms in subcellular compartments, and the effect of isoform expression on cellular processes. To fully understand the dynamic molecular processes taking place in the uterus, it is crucial that we better understand the physiological role of AKT isoforms as well as their function in the emergence of diseases.
Haplo-deficiency of ODF1/HSPB10 in mouse sperm causes relaxation of head-to-tail linkage
Authors: Yang Kefei , Grzmil Pawel , Meinhardt Andreas , Hoyer-Fender Sigrid
Published: August 2014

The small heat shock protein ODF1/HSPB10 is essential for male fertility in mice. Targeted deletion ofOdf1resulted in acephalic sperm in homozygous mice of mixed background (C57BL/6J//129/Sv), whereas heterozygous animals are fully fertile. To further elucidate the function of ODF1, we generated incipient congenic mice with targeted deletion ofOdf1by successive backcrossing on the 129/Sv background. We observed that fecundity of heterozygousOdf1+/−male mice was severely reduced over backcross generations. However, neither aberrant sperm parameters nor sperm anomalies could be observed. Ultra-structural analyses of sperm from incipient congenic heterozygousOdf1+/−males of backcross generation N7 revealed no obvious pathological findings. However, we observed an enlargement of the distance between nuclear membrane and capitulum, indicating a weakening of the sperm head-to-tail coupling. Severe male subfertility provoked by haplo-deficiency of ODF1 is therefore most probably caused by impaired head-to-tail coupling that eventually might induce sperm decapitation on the specific conditions ofin vivofertilisation. As subfertility in haplo-deficient ODF1 male mice could not be diagnosed by semen analysis, it seems to be a paradigm for unexplained infertility that is a frequent diagnosis for male fertility impairment in humans.
Diverse Gene-Silencing Mechanisms with Distinct Requirements for RNA Polymerase Subunits in Zea mays
Authors: Sloan Amy E , Sidorenko Lyudmila , McGinnis Karen M
Published: August 2014

In Zea mays, transcriptional regulation of the b1 (booster1) gene requires a distal enhancer and MEDIATOR OF PARAMUTATION1 (MOP1), MOP2, and MOP3 proteins orthologous to Arabidopsis components of the RNA-dependent DNA methylation pathway. We compared the genetic requirements for MOP1, MOP2, and MOP3 for endogenous gene silencing by two hairpin transgenes with inverted repeats of the a1 (anthocyaninless1) gene promoter (a1pIR) and the b1 gene enhancer (b1IR), respectively. The a1pIR transgene induced silencing of endogenous A1 in mop1-1 and mop3-1, but not in Mop2-1 homozygous plants. This finding suggests that transgene-derived small interfering RNAs (siRNAs) circumvented the requirement for MOP1, a predicted RNA-dependent RNA polymerase, and MOP3, the predicted largest subunit of RNA polymerase IV (Pol IV). Because the Arabidopsis protein orthologous to MOP2 is the second largest subunit of Pol IV and V, our results may indicate that hairpin-induced siRNAs cannot bypass the requirement for the predicted scaffolding activity of Pol V. In contrast to a1pIR, the b1IR transgene silenced endogenous B1 in all three homozygous mutant genotypes—mop1-1, Mop2-1, and mop3-1—suggesting that transgene mediated b1 silencing did not involve MOP2-containing Pol V complexes. Based on the combined results for a1, b1, and three previously described loci, we propose a speculative hypothesis of locus-specific deployment of Pol II, MOP2-containing Pol V, or alternative versions of Pol V with second largest subunits other than MOP2 to explain the mechanistic differences in silencing at specific loci, including one example associated with paramutation.
Predicción de la reprobación de cursos de matemática básicos en las carreras de Física, Meteorología, Matemática, Ciencias Actuariales y Farmacia
Authors: Rojas-Torres Luis
Published: August 2014

Recibido 5 de junio de 2013 • Corregido 4 de abril de 2014 • Aceptado 22 de agosto de 2014Este artículo sintetiza un estudio realizado en el 2013, con el objetivo de predecir la reprobación en cursos de matemática por parte de los estudiantes de las carreras de Farmacia, Matemática, Ciencias Actuariales, Física y Meteorología de la Universidad de Costa Rica (UCR). Mediante la técnica estadística de regresión logística, aplicada a la cohorte del 2010, se pronosticó la  reprobación de los estudiantes de estas carreras en uno de sus cursos introductorios de matemática (Cálculo I para Física y Meteorología, Principios de matemática para Matemática y Ciencias actuariales y ecuaciones diferenciales aplicadas para Farmacia). Para estos modelos se utilizaron, como variables predictivas, los componentes del promedio de admisión a la UCR, el género del estudiante y el porcentaje de ítems correctos en la Prueba de Habilidades Cuantitativas (HC). La variable con mayor importancia en todos los modelos fue HC y los modelos con mejores porcentajes de clasificación correcta de casos fueron las regresiones logísticas. Para los casos utilizados en la estimación de los modelos de Física-Meteorología, Farmacia y Matemática-Ciencias Actuariales se obtuvo un 89.8%, 73.6% y 93.9% de clasificación correcta, respectivamente.
La educación musical competencial en España: ¿Necesidad o deseo?
Authors: Hernández-Bravo José Antonio , Hernández-Bravo Juan Rafael , De Moya-Martínez María Del Valle , Cózar-Gutiérrez Ramón
Published: August 2014

Recibido 11 de febrero de 2013 • Corregido 14 de julio de 2014 • Aceptado 22 de agosto de 2014 El presente artículo tiene como objetivo analizar, de forma crítica, la implementación del sistema competencial en el currículo español y, más concretamente, en el área de educación musical. La sociedad actual, sujeta a transformaciones vertiginosas, demanda una respuesta educativa eficaz y una actualización de los procesos de enseñanza y aprendizaje. En este contexto, se ha constatado la necesidad de adquirir saberes prácticos tanto en docentes como en discentes y de emplearse metodologías activas en el área musical. Así, los contenidos disciplinares han de pasar a un segundo plano y se ha de apostar por el trabajo por competencias que capacite para realizar tareas y resolver problemas en situaciones reales. Sin embargo, teniendo en cuenta el peso que todavía juega el enfoque expositivo tradicional de la clase magistral, estos cambios plantean interrogantes acerca de su viabilidad en la práctica escolar. La naturaleza intrínseca de la música se acerca más al trabajo por competencias que otras materias y, a pesar de que su uso es necesario para musicalizar al estudiante, la realidad es diferente a lo deseado. La novedad del tema y su implicación práctica lo convierten en un foco de interés para estudios y reflexiones, como la que aquí se presenta, en aras de un mejor conocimiento de este fenómeno y del establecimiento de actuaciones educativas eficaces.
Recuperando la capacidad de asombro: La investigación-acción en la formación docente
Authors: Dobles-Trejos Cecilia
Published: August 2014

Recibido 12 de noviembre de 2013 • Corregido 9 de mayo de 2014 • Aceptado 22 de agosto de 2014Es fundamental promover en los procesos de formación docente la recuperación de la capacidad de asombro en el estudiantado universitario. Una herramienta fundamental en este trabajo es la investigación-acción, ya que coloca a quien investiga-educa ante el reto de reconocerse como sujeto de su propia historia y, por tanto, saber que las acciones que realiza tienen un impacto inmediato en la construcción de una nueva propuesta educativa inclusiva. La reflexión que se expone en el siguiente documento es producto de dos proyectos de investigación-extensión en el que participan docentes y estudiantes de educación básica de la Universidad Nacional de Costa Rica.
Valoración del prácticum de los grados del magisterio desde la perspectiva de sus estudiantes
Authors: Mendoza-Lira Michelle , Covarrubias-Apablaza Carmen Gloria
Published: August 2014

Recibido 18 de noviembre de 2013 • Corregido 30 de mayo de 2014 • Aceptado 22 de agosto de 2014El prácticum –entendido no solo como las prácticas externas que los futuros maestros y maestras desarrollan en los centros educativos, sino también las tutorías, seminarios y trabajos realizados en la universidad– constituye un componente esencial dentro de la formación inicial docente. Dada la importancia de este tema, este artículo revela los resultados de un estudio transeccional descriptivo de enfoque cuantitativo, cuyo objetivo es conocer la valoración de una muestra de estudiantes de los grados de maestro en educación primaria y maestro en educación infantil de una universidad pública de Madrid, respecto de la organización del Prácticum I y II, y el soporte recibido de los principales agentes de la universidad y el centro de prácticas. Para obtener esta información, se diseñó un cuestionario dirigido al estudiantado de estas titulaciones, el cual fue respondido por un total de 426 sujetos. Para validar dicho cuestionario, se utilizó la fórmula Lawshe, quien establece un índice de validez de contenido (IVC) de 0.62, con diez jueces expertos, para que el acuerdo no se deba al azar. En tanto, la información entregada por la muestra fue codificada en una base de datos para su posterior tratamiento con el paquete estadístico SPSS 15.0. A través de este software, se realizaron análisis descriptivos para conocer la distribución de la muestra en cada una de las variables definidas en este estudio. Finalmente, los hallazgos revelaron una marcada tendencia a percibir que la institución formadora (universidad) y su agente más representativo (tutor o tutora) no responden a las demandas de apoyo emocional, profesional y pedagógico. Por el contrario, los centros de práctica y el profesorado colaborador no solo son vistos como las principales fuentes de orientación y ayuda durante el Prácticum, sino también como referentes para adquirir y desarrollar competencias profesionales.
El uso de una estrategia híbrida entre aprendizaje basado en problemas y clases magistrales para mejorar aprendizajes
Authors: Acosta-Nassar Carlos Alberto
Published: August 2014

Recibido 25 de febrero de 2014 • Corregido 15 de julio de 2014 • Aceptado 22 de agosto de 2014En este artículo se aborda el problema de captar la atención del estudiantado de niveles intermedios de la carrera de Ingeniería Mecánica y Agrícola en el curso de Termodinámica 1, con el objetivo fundamental de ayudar a los discentes a mejorar su proceso de aprendizaje. Se propuso una estrategia docente híbrida fundamentada en los principios del aprendizaje basado en problemas (ABP) en conjunto con clases magistrales y se combinó con recursos didácticos digitales y tradicionales, con el fin de encontrar uno idóneo para minimizar el problema atencional. Se desarrolló la estrategia sensibilizando a los estudiantes a involucrarse en su proceso de formación. Se emplearon presentaciones de PowerPoint con video clips, la pizarra tradicional y la pizarra digital para desarrollar los temas teóricos y la solución de los problemas escogidos para la estrategia de ABP. Por último, se procedió a evaluar la estrategia y a analizar los resultados de cuyo análisis se concluye que la creación de una estrategia híbrida entre el ABP y las clases magistrales tradicionales es óptima para mejorar el aprendizaje de los estudiantes de Termodinámica 1. Además, como logro secundario se encontró que el recurso didáctico óptimo es la pizarra digital.
Computational modelling of Yorùbá numerals in a number-to-text conversion system
Authors: Akinadé Olúgbénga O. , Ọdẹ́jọbí Ọdẹ́túnjí A.
Published: August 2014

In this paper, we examine the processes underlying the Yorùbá numeral system and describe a computational system that is capable of converting cardinal numbers to their equivalent Standard Yorùbá number names. First, we studied the  mathematical and linguistic basis of the Yorùbá numeral system so as to formalise its arithmetic and syntactic procedures. Next, the process involved in formulating a Context-Free Grammar (CFG) to capture the structure of the Yorùbá numeral system was highlighted.  Thereafter, the model was reduced into a set of computer programs to implement the numerical to lexical conversion process. System evaluation was done by ranking the output from the software and comparing the output with the representations given by a group of Yorùbá native speakers. The result showed that the system gave correct representation for numbers and produced a recall of 100% with respect to the collected corpus. Our future study is focused on developing a text normalisation system that will produce number names for other numerical expressions such as ordinal numbers, date, time, money, ratio, etc. in Yorùbá text.
Bimorphisms and synchronous grammars
Authors: Shieber Stuart M.
Published: August 2014

We tend to think of the study of language as proceeding by characterizing the strings and structures of a language, and we think of natural language processing as using those structures to build systems of utility in manipulating the language. But many language-related problems are more fruitfully viewed as requiring the specification of a relation between two languages, rather than the specification of a single language. We provide a synthesis and extension of work that unifies two approaches to such language relations: the automata-theoretic approach based on tree transducers that transform trees to their counterparts in the relation, and the grammatical approach based on synchronous grammars that derive pairs of trees in the relation. In particular, we characterize synchronous tree-substitution grammars and synchronous tree-adjoining grammars in terms of bimorphisms, which have previously been used to characterize tree transducers. In the process, we provide new approaches to formalizing the various concepts: a metanotation for describing varieties of tree automata and transducers in equational terms; a rigorous formalization of tree-adjoining and tree-substitution grammars and their synchronous counterparts, using trees over ranked alphabets; and generalizations of tree-adjoining grammar allowing multiple adjunction.
Pathophysiological and Clinical Approach to Cirrhotic Cardiomyopathy
Authors: Páll Alida , Czifra Árpád , Vitális Zsuzsanna , Papp Mária , Paragh György , Szabó Zoltán
Published: August 2014

Hyperdynamic circulation, systolic and diastolic left ventricular dysfunction and certain electrophysiological abnormalities have been associated with cirrhosis and known for a long time. These clinical features have been introduced as cirrhotic cardiomyopathy (CCM), which is characterized by blunted myocardial contractile responsiveness to physical, physiological and pharmacological stress. Importantly, cardiac dysfunction can be reversible and can improve due to effective medical treatment and also after liver transplantation. Echocardiography and electrocardiography are essential tools for recognizing the characteristic changes in the myocardial function and also the alterations in the electrophysiological properties of the heart. Laboratory markers are auxiliary modalities further aiding the establishment of the correct diagnosis. In this review, we aimed to collect the pathophysiological background and clinical characteristics of CCM with the intention of summarizing the current possibilities for the diagnosis establishment and treatment of this cardio-hepatic disorder.Abbreviations: A: late diastolic transmitral peak flow velocity; ACE: angiotensin converting enzyme; ANP: atrial natriuretic peptide; ARB: angiotensin receptor blocker; BNP: brain natriuretic peptide; cAMP: cyclic adenosine monophosphate; CCM: cirrhotic cardiomyopathy; CGRP: calcitonin gene-related peptide; CO: carbon monoxide; DD: diastolic dysfunction; DT: deceleration time; E: early diastolic transmitral peak flow velocity; Ea: early diastolic velocity of the septal mitral annulus; EF: ejection fraction; MUGA: Multi Gated Acquisition Scan; NO: nitric oxide; NSBB: non-selective beta-blocker; pro-BNP: pro-brain natriuretic peptide; QTc: corrected QT interval; RAAS: renin-angiotensin aldosterone system; RALES: Randomized Aldactone Evaluation Study; suPAR: urokinase-type plasminogen activator receptor; TDI: Tissue Doppler Imaging; TIPS: transjugular intrahepatic portosystemic shunt; TNF-alpha: tumor necrosis factor-alpha.
Rectal Pseudolipomatosis
Authors: Titiz Hafize , Ermis Fatih , Erdem Havva
Published: August 2014

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Respiratory Complications in Outpatient Endoscopy with Endoscopist-Directed Sedation
Authors: Friedrich Kilian , Scholl Sabine G. , Beck Sebastian , Gotthardt Daniel , Stremmel Wolfgang , Rex Douglas K. , Sieg Andreas
Published: August 2014

Background & Aims: Respiratory complications represent an important adverse event of endoscopic procedures. We screened for respiratory complications after endoscopic procedures using a questionnaire and followed-up patients suggestive of respiratory infection.Method: In this prospective observational, multicenter study performed in Outpatient practices of gastroenterology we investigated 15,690 patients by questionnaires administered 24 hours after the endoscopic procedure.Results: 832 of the 15,690 patients stated at least one respiratory symptom after the endoscopic procedure: 829 patients reported coughing (5.28%), 23 fever (0.15%) and 116 shortness of breath (SOB, 0.74%); 130 of the 832 patients showed at least two concomitant respiratory symptoms (107 coughing + SOB, 17 coughing + fever, 6 coughing + coexisting fever + SOB) and 126 patients were followed-up to assess their respiratory complaints. Twenty-nine patients (follow-up: 22.31%, whole sample: 0.18%) reported signs of clinically evident respiratory infection and 15 patients (follow-up: 11.54%; whole sample: 0.1%) received therefore antibiotic treatment. Coughing or vomiting during the endoscopic procedure resulted in a 156.12-fold increased risk of respiratory complications (95% CI: 67.44 - 361.40) and 520.87-fold increased risk of requiring antibiotic treatment (95% CI: 178.01 - 1524.05). All patients of the follow-up sample who coughed or vomited during endoscopy developed clinically evident signs of respiratory infection and required antibiotic treatment while this occurred in a significantly lower proportion of patients without these symptoms (17.1% and 5.1%, respectively).Conclusions: We demonstrated that respiratory complications following endoscopic sedation are of comparably high incidence and we identified major predictors of aspiration pneumonia which could influence future surveillance strategies after endoscopic procedures.
Intrahepatic Biliary Paracoccidioidomycosis Mimicking Cholangiocarcinoma
Authors: Steinbrück Klaus , Fernandes Reinaldo , Campos Carlos F. F. , Bento Giuliano , Stoduto Gustavo , Auel Thomas
Published: August 2014

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Determining Histological Remission in Coeliac Disease: Can Glycoprotein-2 Antibodies Help?
Authors: Mooney Peter D. , Sanders David S.
Published: August 2014

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Pneumatosis Intestinalis from Thromboembolism: a Fatal Complication in a Patient with Total Artificial Heart
Authors: Edmonds Peter J. , Thongprayoon Charat , Thamcharoen Natanong , Cheungpasitporn Wisit
Published: August 2014

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Giant Solitary Gastric Peutz-Jeghers Polyp Mimicking a Malignant Gastric Tumor: the Largest Described in Literature
Authors: Lunca Sorinel , Porumb Vlad , Velenciuc Natalia , Ferariu Dan , Dimofte Gabriel
Published: August 2014

A solitary Peutz-Jeghers polyp is defined as a unique polyp occurring without associated mucocutaneous pigmentation or a family history of Peutz-Jeghers syndrome. Gastric solitary localization is a rare event, with only eight reported cases to date. We report herein the case of a 43-year old woman who presented with upper gastrointestinal bleeding, severe anemia, weight loss and asthenia. Endoscopy revealed a giant polypoid tumor with signs of neoplastic invasion of the cardia, with pathological aspect suggesting a Peutz-Jeghers hamartomatous polyp. Computed tomography suggested a malignant gastric tumor and a total gastrectomy was performed. The pathological specimen showed a giant 150/70/50 mm polypoid tumor and immunochemistry established the final diagnostic of a Peutz-Jegers type polyp. This is the largest solitary Peutz-Jeghers gastric polyp reported until now, and the second one mimicking a gastric malignancy with lymph node metastasis.
Centrifuge modelling of root-reinforced soil slope subjected to rainfall infiltration
Authors: Eab K. H. , Takahashi A. , Likitlersuang S.
Published: August 2014

Slope instability induced by heavy rainfall is a serious geotechnical hazard all over the world. The characteristics of water flow, pore water pressure changes and shear strength of the soil are the main factors involved in slope failure mechanisms. This paper describes soil slope failure induced by rainfall using a rainfall simulator in a geotechnical centrifuge. To study a soil-bioengineering slope stabilisation technique in a small centrifuge, a sloping rooted surface layer was simulated by mixing polyester fibres into the soil. The test results indicate that a rise in the groundwater table due to rainwater infiltration was responsible for slope failure and failure near the toe propagated upslope in a bare soil slope. On the other hand, a slope whose surface was reinforced with roots exhibited small deformation without failure under heavy rainfall (intensity of 20 mm/h) for a duration of 15 h at prototype scale. The test results also reveal that roots can help to reduce the infiltration of rainwater into the ground, delay a rise in groundwater table and increase the shear strength of the soil.
Resistance of MgO–GGBS and CS–GGBS stabilised marine soft clays to sodium sulfate attack
Authors: YI Y. , LI C. , LIU S. , AL-TABBAA A.
Published: August 2014

Reactive magnesia (MgO) and carbide slag (CS) were used to activate ground granulated blastfurnace slag (GGBS) to stabilise a marine soft clay, and the stabilised clays were subjected to accelerated sodium sulfate attack. The results indicated MgO–GGBS stabilised clay was nearly inert to this sodium sulfate solution. The resistance of CS–GGBS stabilised clay to sodium sulfate attack was lower than that of MgO–GGBS stabilised clay, but higher than that of Portland cement stabilised clay. Unlike CS–GGBS stabilised clay, there was no calcium aluminate hydrate or alumino-ferrite monosulfate produced in MgO–GGBS stabilised clay, and hence no ettringite, which would cause deterioration, formed when exposed to sodium sulfate.
Bridging the gap: university to professional qualifications
Authors: Thompson Pauline , Surgeoner Donna
Published: August 2014

The jump from higher education to professional qualifications can be challenging. Engineering students do not necessarily leave university with the reflective and planning skills required for initial professional development (IPD). Many trainees do not understand IPD. These professional skills are not well covered in most UK universities. If this gap can be bridged then graduates may be more employable. This paper presents a case study where an IPD-style portfolio is used to assess the challenging breadth of the subject of sustainability with a large and diverse cohort of students. The details of the assessment, teaching methods and marking criteria are described and the challenges presented are discussed. Feedback was gathered from current students from the past 3 years, representatives of industry and the professional institutions. Ten companies were consulted including detailed interviews with recent graduates and senior engineers responsible for staff development and links to professional institutions. They were enthusiastic about the ideas presented in this work. This approach could be adopted widely throughout the university engineering curriculum. Professional institutions could consider how they might benefit from closer links with higher education. As professional institutions implement online systems for IPD they could consider ways to involve undergraduate students in the process.
A Case of Trap Sequence with Immense Acardiac Twin
Authors: Amaliev Georgi I. , Malinova Maria L. , Pehlivanov Blagovest K. , Ivancheva Hristina A.
Published: August 2014

Twin-reversed arterial perfusion sequence is a rare complication of monochorionic twin pregnancy in which an anomalous acardiac fetus is hemodynamically dependent on its structurally normal “pump” twin. Early diagnosis is essential for improving perinatal prognosis for the normal twin. In this case report we present a case of TRAP sequence with immense acardiac twin with favorable outcome, emphasizing the importance of ultrasound imaging, follow-up and timing of delivery in this complicated pregnancy.
EcoForge: Energieeffiziente Prozesskette zur Herstellung von Hochleistungs-Schmiedebauteilen*
Authors: Fischer Martin , Dickert Hans-Henning , Bleck Wolfgang , Huskic Adis , Kazhai Mohammad , Hadifi Tarik , Bouguecha Anas , Behrens Bernd-Arno , Labanova Nadja , Felde Alexander , Liewald Mathias , Egorov Fedor , Gabrecht Martin , Brinksmeier Ekkard , Reimche Wilfried , Bruchwald Oliver , Frackowiak Wojciech , Maier Hans Jürgen , Bucquet Thibaud , Hinrichs Björn , Fritsching Udo , Hoja Timo , Hoffmann Franz , Zoch Hans-Werner
Published: August 2014

Kurzfassung

In der “Leittechnologie für Morgen – Ressourceneffiziente Prozesskette für Hochleistungsbauteile” (EcoForge) wird eine verkürzte Schmiedeprozesskette für Hochleistungsbauteile entwickelt, die Energie-Einsparungen von > 30 % ermöglicht. Diese Prozesskette wird für hochfeste duktile bainitische Stähle (HDB) optimiert. Dies geschieht, indem unter direkter Ausnutzung der Schmiedewärme unmittelbar an den Schmiedeprozess eine auf den Stahl zugeschnittene Wärmebehandlung vorgenommen wird. Dabei wird die Gefügeumwandlung im Bauteil durch eine neuartige Hochtemperatur-Wirbelstromtechnik während der Abkühlung ermittelt. Die Messsignale werden online erfasst und stehen zur Steuerung der Temperaturführung im Abkühlpfad zur Verfügung. Noch während der Wärmebehandlung, insbesondere der isothermen Wärmebehandlung im Gebiet des Bainits und in ihrem Anschluss, werden weitere Bearbeitungsschritte wie die Heißzerspanung und die Lauwarmumformung vorgenommen. Die Bearbeitungsschritte finden bei Bauteiltemperaturen von ca. 300–500 °C statt. Diese hohen Temperaturen ermöglichen die Bearbeitung des Zielgefüges bei reduzierten mechanischen Belastungen der Werkzeuge. Die erzeugten Mikrostrukturen werden mittels einer neuentwickelten REM-Bildanalyseroutine quantitativ charakterisiert. Simultan zu den experimentellen Untersuchungen wird die gesamte Prozesskette numerisch abgebildet und die Gefügeevolution der Schmiedebauteile im Prozess simuliert.
Disseminated histoplasmosis as presenting feature of acquired immunodeficiency syndrome: a case report
Authors: Yasmin Roksana , Rahim Muhammad Abdur , Haque Hasna Fahmima , Dewan Pratik , Ahmed Jamal Uddin , Ahmed AKM Shaheen , Hossain Md Delwar , Musa AKM , Uddin Khwaja Nazim
Published: August 2014

Histoplasmosis is a mild self-limiting respiratory illness in immune-competent individuals. It disseminates in immune-suppressed states like patients with human immunodeficiency virus (HIV) infection, haematological malignancies, post transplant states and patients receiving immunesuppressive therapy. Here we report a case of disseminated histoplasmosis in a 45 year old diabetic, returning worker who presented with fever, cough, rash, oro-genital ulcer and weight loss. He was anaemic, there was crepitation on lung auscultation and hepatomegaly. Diagnostic workup revealed HIV infection with disseminated histoplasmosis. Intravenous amphotericin B was started along with other supportive therapy and for anti-retroviral therapy he was sent to a referral center. Being an uncommon condition in our perspective, we are reporting the case. DOI: http://dx.doi.org/10.3329/bjmed.v24i2.20221 Bangladesh J Medicine 2013; 24 : 78-81
Systemic lupus erythematosus in male: two case reports
Authors: Hossain Md Ismail , Jahan Shah Md Sarwer , Haque Md Ashraful , Alam ABM Mobasher , Ahmed Mainuddin , Hossain Md Zakir
Published: August 2014

Systemic lupus erythematosus (SLE) is the most common multisystem connective tissue disease. Around 90% of affected individuals are women, with peak onset in the second and third decades. Tissues of all system are damaged by pathogenic auto-antibodies and immune complexes. We report here two cases of SLE in male patient, presented with typical features of SLE. Though the disease is rare in male, but such type of manifestations should be investigated properly to exclude SLE. DOI: http://dx.doi.org/10.3329/bjmed.v24i2.20222 Bangladesh J Medicine 2013; 24 : 82-85
Heart failure presented with massive pleural effusion and mediastinal lymphadenopathy: a rare case report
Authors: Islam Mohammad Shahidul , Tabassum Humayara , Jahan Sharah , Masud Mohammad Shahin , Amin Muhammad Al , Kabir Ahmedul
Published: August 2014

Heart failure may present with diverse manifestation. It is far most common cause of bilateral transudative pleural effusion. In very unusual case, it may present with only massive transudative pleural effusion without cardiomegaly and other features of heart failure such as leg odema, tender hepatomegaly or congested liver. We presented a case that present with massive transudative pleural effusion with mediastinal lymphadenopathy evidenced by CT scan of chest and treated successfully with diuretics. DOI: http://dx.doi.org/10.3329/bjmed.v24i2.20223 Bangladesh J Medicine 2013; 24 : 86-88
Congenital intestinal Lymphangactasia
Authors: Amin Md Robed , Islam Mohammad Rafiqul
Published: August 2014

Abstract not available DOI: http://dx.doi.org/10.3329/bjmed.v24i2.20224 Bangladesh J Medicine 2013; 24 : 89
Market model analysis and forecasting behavior of watermelon production in Bangladesh
Authors: Khanam Murshida , Hafsa Umme
Published: August 2014

An attempt has been made to study various models regarding watermelon production in Bangladesh and to identify the best model that may be used for forecasting purposes. Here, supply, log linear, ARIMA, MARMA models have been used to do a statistical analysis and forecasting behavior of production of watermelon in Bangladesh by using time series data covering whole Bangladesh. It has been found that, between the supply and log linear models; log linear is the best model. Comparing ARIMA and MARMA models it has been concluded that ARIMA model is the best for forecasting purposes. DOI: http://dx.doi.org/10.3329/bjsr.v26i1-2.20230 Bangladesh J. Sci. Res. 26(1-2): 47-56, December-2013
Effects of additional amount of carbon micro-coils on the dielectric properties of its composite sheet
Authors: Nessa Meherun
Published: August 2014

The morphology and dielectric properties of carbon micro-coils (CMC) composite sheet wereexamined. Frequency dependence of dielectric parameters; dielectric loss angle (?), dielectric losstangent (tan?) and relative dielectric constant ( ?r) were measured on single and double-helixcomposite sheet. It was found that these parameters of CMC/polysilicone composites extensivelychanged with the additional amount of CMC with polysilicone resine. It was also observed that thehigher additional amount (wt%) of CMC is appropriate for high response. DOI: http://dx.doi.org/10.3329/jbas.v38i1.20210 Journal of Bangladesh Academy of Sciences, Vol. 38, No. 1, 39-47, 2014
Investigation of physico-mechanical properties of natural palm fiber reinforced polyvinyl chloride composites
Authors: Saha Indrajit , Sarkar Sanjib Kumar
Published: August 2014

Fiber reinforced polymer composites played a dominant role in a variety of applications for their high specific strength and modulus. The present work describes the effects of palm fiber addition on physico-mechanical properties of polyvinyl chloride (PVC) composites. The tensile strength and Youngs modulus of the fabricated products increased, while the bulk density, flexural strength and tangent modulus decreased with the increase of fiber addition. The tensile strain decreased with the increase of fiber addition up to 10% and after that it remained nearly constant, while flexural strain remained increasing. There was an initial differential thermal analysis (DTA) peak for both palm fiber and composite, whereas PVC did not have that peak due to water absorption. Thermal analysis of PVC-palm fiber composites has shown that thermal degradation of PVC started ahead of palm fiber. The thermal stability of composite was found to be the average of palm fiber and PVC foam sheet DOI: http://dx.doi.org/10.3329/jbas.v38i1.20215 Journal of Bangladesh Academy of Sciences, Vol. 38, No. 1, 83-92, 2014
Influence of thickness on the optical properties of Sb doped ZnO thin films
Authors: Hoq E , Bhuiyan MRA , Begum J
Published: August 2014

Sb doped ZnO thin films having various thicknesses have been prepared onto glass substrate by using thermal evaporation method. The atomic compositions of the grown films have been determined by Energy Dispersive Analysis of X-ray (EDAX) method. The optical properties were measured by using a UV-VIS-NIR spectrophotometer (300 to 2500 nm). The EDAX analysis revealed that Sb is doped into the ZnO films. Optical properties showed high absorption coefficient (~105/cm) that direct allowed transition band gap. The optical band gap of the ZnO thin films became reduced due to the doping of Sb. DOI: http://dx.doi.org/10.3329/jbas.v38i1.20217 Journal of Bangladesh Academy of Sciences, Vol. 38, No. 1, 93-96, 2014
An Acausal Li-Ion Battery Pack Model for Automotive Applications
Authors: Uddin Kotub , Picarelli Alessandro , Lyness Christopher , Taylor Nigel , Marco James
Published: August 2014

In this work, a novel acausal and reconfigurable battery pack model is presented. The model structure adopted for the battery cell is based on an equivalent circuit representation. The circuit elements are modified to take account of both hysteresis and diffusion limitation. The latter is known to be a nonlinear function of large operating currents or long operating times. It is shown that the integration of a current dependent time constant within the cell model better emulates the solid diffusional dynamics of lithium intercalation into the active material under large electrical loads. The advantages of an acausal modeling approach, when scaling-up individual cell models into a complete battery system are also presented. Particular consideration is given to emulating the impact of cell to cell variations on pack performance. Using statistical analysis of battery tests, cell model parameter variations are characterized and quantified. The cell and scaled-up pack model are parameterized for a number of commercially available cell formats, energy capacities and chemistries. The new models are validated using transient, real-world, electrical data measured from an electric vehicle (EV) operating within an urban environment.
Altered Gene Transcription in Human Cells Treated with Ludox® Silica Nanoparticles
Authors: Fede Caterina , Millino Caterina , Pacchioni Beniamina , Celegato Barbara , Compagnin Chiara , Martini Paolo , Selvestrel Francesco , Mancin Fabrizio , Celotti Lucia , Lanfranchi Gerolamo , Mognato Maddalena , Cagnin Stefano
Published: August 2014

Silica (SiO2) nanoparticles (NPs) have found extensive applications in industrial manufacturing, biomedical and biotechnological fields. Therefore, the increasing exposure to such ultrafine particles requires studies to characterize their potential cytotoxic effects in order to provide exhaustive information to assess the impact of nanomaterials on human health. The understanding of the biological processes involved in the development and maintenance of a variety of pathologies is improved by genome-wide approaches, and in this context, gene set analysis has emerged as a fundamental tool for the interpretation of the results. In this work we show how the use of a combination of gene-by-gene and gene set analyses can enhance the interpretation of results of in vitro treatment of A549 cells with Ludox® colloidal amorphous silica nanoparticles. By gene-by-gene and gene set analyses, we evidenced a specific cell response in relation to NPs size and elapsed time after treatment, with the smaller NPs (SM30) having higher impact on inflammatory and apoptosis processes than the bigger ones. Apoptotic process appeared to be activated by the up-regulation of the initiator genes TNFa and IL1b and by ATM. Moreover, our analyses evidenced that cell treatment with LudoxÒ silica nanoparticles activated the matrix metalloproteinase genes MMP1, MMP10 and MMP9. The information derived from this study can be informative about the cytotoxicity of Ludox® and other similar colloidal amorphous silica NPs prepared by solution processes.
Study on an Air Quality Evaluation Model for Beijing City Under Haze-Fog Pollution Based on New Ambient Air Quality Standards
Authors: Li Li , Liu Dong-Jun
Published: August 2014

Since 2012, China has been facing haze-fog weather conditions, and haze-fog pollution and PM2.5 have become hot topics. It is very necessary to evaluate and analyze the ecological status of the air environment of China, which is of great significance for environmental protection measures. In this study the current situation of haze-fog pollution in China was analyzed first, and the new Ambient Air Quality Standards were introduced. For the issue of air quality evaluation, a comprehensive evaluation model based on an entropy weighting method and nearest neighbor method was developed. The entropy weighting method was used to determine the weights of indicators, and the nearest neighbor method was utilized to evaluate the air quality levels. Then the comprehensive evaluation model was applied into the practical evaluation problems of air quality in Beijing to analyze the haze-fog pollution. Two simulation experiments were implemented in this study. One experiment included the indicator of PM2.5 and was carried out based on the new Ambient Air Quality Standards (GB 3095-2012); the other experiment excluded PM2.5 and was carried out based on the old Ambient Air Quality Standards (GB 3095-1996). Their results were compared, and the simulation results showed that PM2.5 was an important indicator for air quality and the evaluation results of the new Air Quality Standards were more scientific than the old ones. The haze-fog pollution situation in Beijing City was also analyzed based on these results, and the corresponding management measures were suggested.
Global School-Based Childhood Obesity Interventions: A Review
Authors: Ickes Melinda , McMullen Jennifer , Haider Taj , Sharma Manoj
Published: August 2014

Background: The issue of childhood overweight and obesity has become a global public health crisis. School-based interventions have been developed and implemented to combat this growing concern. The purpose of this review is to compare and contrast U.S. and international school-based obesity prevention interventions and highlight efficacious strategies. Methods: A systematic literature review was conducted utilizing five relevant databases. Inclusion criteria were: (1) primary research; (2) overweight or obesity prevention interventions; (3) school-based; (4) studies published between 1 January 2002 through 31 December 2013; (5) published in the English language; (6) child-based interventions, which could include parents; and (7) studies that reported outcome data. Results: A total of 20 interventions met the inclusion criteria. Ten interventions each were implemented in the U.S. and internationally. International interventions only targeted elementary-aged students, were less likely to target low-income populations, and were less likely to be implemented for two or more years in duration. However, they were more likely to integrate an environmental component when compared to U.S. interventions. Discussion: Interventions implemented in the U.S. and internationally resulted in successful outcomes, including positive changes in student BMI. Yet, varying approaches were used to achieve success, reinforcing the fact that a one-size-fits-all approach is not necessary to impact childhood obesity. However, building on successful interventions, future school-based obesity prevention interventions should integrate culturally specific intervention strategies, aim to incorporate an environmental component, and include parents whenever possible. Consideration should be given to the potential impact of long-term, frequent dosage interventions, and subsequent follow-up should be given attention to determine long-term efficacy.
Cyclic Peptide-Capped Gold Nanoparticles for Enhanced siRNA Delivery
Authors: Shirazi Amir , Paquin Karissa , Howlett Niall , Mandal Dindyal , Parang Keykavous
Published: August 2014

Previously, we have reported the synthesis of a homochiral l-cyclic peptide [WR]5 and its use for delivery of anti-HIV drugs and biomolecules. A physical mixture of HAuCl4 and the peptide generated peptide-capped gold nanoparticles. Here, [WR]5 and [WR]5-AuNPs were tested for their efficiency to deliver a small interfering RNA molecule (siRNA) in human cervix adenocarcinoma (HeLa) cells. Flow cytometry investigation revealed that the intracellular uptake of a fluorescence-labeled non-targeting siRNA (200 nM) was enhanced in the presence of [WR]5 and [WR]5-AuNPs by 2- and 3.8-fold when compared with that of siRNA alone after 24 h incubation. Comparative toxicity results showed that [WR]5 and [WR]5-AuNPs were less toxic in cells compared to other available carrier systems, such as Lipofectamine.
Evaluation of a Global Soil Moisture Product from Finer Spatial Resolution SAR Data and Ground Measurements at Irish Sites
Authors: Pratola Chiara , Barrett Brian , Gruber Alexander , Kiely Gerard , Dwyer Edward
Published: August 2014

In the framework of the European Space Agency Climate Change Initiative, a global, almost daily, soil moisture (SM) product is being developed from passive and active satellite microwave sensors, at a coarse spatial resolution. This study contributes to its validation by using finer spatial resolution ASAR Wide Swath and in situ soil moisture data taken over three sites in Ireland, from 2007 to 2009. This is the first time a comparison has been carried out between three sets of independent observations from different sensors at very different spatial resolutions for such a long time series. Furthermore, the SM spatial distribution has been investigated at the ASAR scale within each Essential Climate Variable (ECV) pixel, without adopting any particular model or using a densely distributed network of in situ stations. This approach facilitated an understanding of the extent to which geophysical factors, such as soil texture, terrain composition and altitude, affect the retrieved ECV SM product values in temperate grasslands. Temporal and spatial variability analysis provided high levels of correlation (p < 0.025) and low errors between the three datasets, leading to confidence in the new ECV SM global product, despite limitations in its ability to track the driest and wettest conditions.
Development of Phase Detection Schemes Based on Surface Plasmon Resonance Using Interferometry
Authors: Kashif Muhammad , Bakar Ahmad , Arsad Norhana , Shaari Sahbudin
Published: August 2014

Surface plasmon resonance (SPR) is a novel optical sensing technique with a unique ability to monitor molecular binding in real-time for biological and chemical sensor applications. Interferometry is an excellent tool for accurate measurement of SPR changes, the measurement and comparison is made for the sensitivity, dynamic range and resolution of the different analytes using interferometry techniques. SPR interferometry can also employ phase detection in addition to the amplitude of the reflected light wave, and the phase changes more rapidly compared with other approaches, i.e., intensity, angle and wavelength. Therefore, the SPR phase interferometer offers the advantages of spatial phase resolution and high sensitivity. This work discusses the advancements in interferometric SPR methods to measure the phase shifts due to refractive index changes. The main application areas of SPR sensors are demonstrated, i.e., the Fabry-Perot interferometer, Michelson interferometer and Mach-Zehnder interferometer, with different configurations. The three interferometers are discussed in detail, and solutions are suggested to enhance the performance parameters that will aid in future biological and chemical sensors.