bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk factors of sudden death in young adult patients with myelomeningocele
Authors: Jernigan Sarah C. , Berry Jay G. , Graham Dionne A. , Bauer Stuart B. , Karlin Lawrence I. , Hobbs Nedda M. , Scott R. Michael , Warf Benjamin C.
Published: February 2012

Object

Although survival for patients with myelomeningocele has dramatically improved in recent decades, the occasional occurrence of sudden, unexplained death in young adult patients with myelomeningocele has been noted by the authors. This study was undertaken to determine risk factors for sudden death in this population.

Methods

The authors performed a retrospective chart review of patients born between 1978 and 1990 who received care at Children's Hospital Boston. The relationship between sudden death and patient demographics, presence of CSF shunt and history of shunt revisions, midbrain length as a marker for severity of hindbrain malformation, seizures, pulmonary and ventilatory dysfunction, body mass index, scoliosis, renal dysfunction, and cardiac disease was evaluated using the t-test, Fisher exact test, and logistic regression analysis.

Results

The age range for 106 patients in the study cohort was 19–30 years, with 58 (54.7%) women and 48 (45.3%) men. Six patients, all of whom were young women, experienced sudden death. In multivariate analysis, female sex, sleep apnea, and midbrain elongation ≥ 15 mm on MR imaging remained significantly associated with a higher risk of sudden death. These risk factors were cumulative, and female patients with sleep apnea and midbrain length ≥ 15 mm had the greatest risk (adjusted risk ratio 24.0, 95% CI 7.3–79.0; p < 0.05). No other comorbidities were found to significantly increase the risk of sudden death.

Conclusions

Young adult women with myelomeningocele are at significantly increased risk of sudden death in the setting of midbrain elongation and sleep apnea. Further investigation is needed to determine the benefit of routine screening to identify at-risk patients for closer cardiopulmonary monitoring and treatment.
Preoperative third ventricular bowing as a predictor of endoscopic third ventriculostomy success
Authors: Dlouhy Brian J. , Capuano Ana W. , Madhavan Karthik , Torner James C. , Greenlee Jeremy D. W.
Published: February 2012

Object

Patients with hydrocephalus often present with both intraventricular obstructive and communicating components, and determination of the predominant component is difficult. Other investigators have observed that third ventricular floor deformation, or “bowing” of the third ventricular floor, is a good indicator of intraventricular obstructive hydrocephalus, resulting in higher success rates with endoscopic third ventriculostomy (ETV). However, additional third ventricular bowing assessment and statistical evidence demonstrating a difference in ETV outcome with third ventricular bowing is needed. The authors hypothesized that patients with preoperative bowing of the third ventricle would exhibit greater long-term success rates after ETV and that lack of bowing would result in increased failure rates after ETV.

Methods

The authors determined success and failure for 59 ETVs performed in 56 patients, and recorded patient age, time to failure, and preoperative third ventricular anatomy, as well as history of infection, intraventricular hemorrhage, and previous shunt. Third ventricular anatomy was assessed on MR imaging for bowing, which was classified as any of the following: depression of the third ventricular floor, enlargement of the supraoptic recess, anterior curvature of the lamina terminalis, dilation of the proximal aqueduct to a greater extent than the distal aqueduct, and blunting or posterior bowing of the suprapineal recess. Univariate and multivariate analyses of ETV failure and the time to failure were performed using logistic regression and the Cox proportional hazards model, respectively.

Results

After adjusting for patient age and history of infection, there was a significant association between lack of anterior third ventricular preoperative bowing (either lamina terminalis, supraoptic recess, or third ventricular floor) and ETV failure (adjusted HR 2.79, 95% CI 1.08–7.20). Of the patients with bowing, 70.5% experienced success with ETV, as did 33.3% of the patients without bowing. Among the individual structures, absence of bowing in the anterior aspect of the third ventricular floor was significantly associated with censored time to ETV failure (multivariate HR 2.59, 95% CI 1.01–6.66; final model including age and history of infection).

Conclusions

The presence of preoperative third ventricular bowing is predictive of ETV success, with nearly a 3-fold likelihood of success compared with patients treated with ETV in the absence of such bowing. Although bowing is predictive, 33% of patients without bowing were also treated successfully with ETV.
Pharmacological Mechanisms Underlying Gastroprotective Activities of the Fractions Obtained from Polygonum minus in Sprague Dawley Rats
Authors: Qader Suhailah Wasman , Abdulla Mahmood Ameen , Chua Lee Suan , Sirat Hasnah Mohd , Hamdan Salehhuddin
Published: February 2012

The leaves of Polygonum minus were fractionated using an eluting solvent to evaluate the pharmacological mechanisms underlying the anti-ulcerogenic activity of P. minus. Different P. minus fractions were obtained and evaluated for their ulcer preventing capabilities using the ethanol induction method. In this study, Sprague Dawley rats weighing 150–200 g were used. Different parameters were estimated to identify the active fraction underlying the mechanism of the gastroprotective action of P. minus: the gastric mucus barrier, as well as superoxide dismutase, total hexosamine, and prostaglandin synthesis. Amongst the five fractions from the ethanolic extract of P. minus, the ethyl acetate:methanol 1:1 v/v fraction (F2) significantly (p < 0.005) exhibited better inhibition of ulcer lesions in a dose-dependent manner. In addition, rats pre-treated with F2 showed a significant elevation in superoxide dismutase (SOD), hexosamine and PGE2 levels in the stomach wall mucosa in a dose-dependent matter. Based on these results, the ethyl acetate:methanol 1:1 v/v fraction was considered to be the best fraction for mucous protection in the ethanol induction model. The mechanisms underlying this protection were attributed to the synthesis of antioxidants and PGE2.
Molecular Diagnostic and Pathogenesis of Hereditary Hemochromatosis
Authors: Santos Paulo C. J. L. , Krieger Jose E. , Pereira Alexandre C.
Published: February 2012

Hereditary hemochromatosis (HH) is an autosomal recessive disorder characterized by enhanced intestinal absorption of dietary iron. Without therapeutic intervention, iron overload leads to multiple organ damage such as liver cirrhosis, cardiomyopathy, diabetes, arthritis, hypogonadism and skin pigmentation. Most HH patients carry HFE mutant genotypes: homozygosity for p.Cys282Tyr or p.Cys282Tyr/p.His63Asp compound heterozygosity. In addition to HFE gene, mutations in the genes that encode hemojuvelin (HJV), hepcidin (HAMP), transferrin receptor 2 (TFR2) and ferroportin (SLC40A1) have been associated with regulation of iron homeostasis and development of HH. The aim of this review was to identify the main gene mutations involved in the pathogenesis of type 1, 2, 3 and 4 HH and their genetic testing indication. HFE testing for the two main mutations (p.Cys282Tyr and p.His63Asp) should be performed in all patients with primary iron overload and unexplained increased transferrin saturation and/or serum ferritin values. The evaluation of the HJV p.Gly320Val mutation must be the molecular test of choice in suspected patients with juvenile hemochromatosis with less than 30 years and cardiac or endocrine manifestations. In conclusion, HH is an example that genetic testing can, in addition to performing the differential diagnostic with secondary iron overload, lead to more adequate and faster treatment.
Olmesartan Attenuates the Impairment of Endothelial Cells Induced by Oxidized Low Density Lipoprotein through Downregulating Expression of LOX-1
Authors: Zhang Hua , Ma Genshan , Yao Yuyu , Qian Huidong , Li Weizhang , Chen Xinjun , Jiang Wenlong , Zheng Ruolong
Published: February 2012

Oxidized low density lipoprotein (ox-LDL) and its receptor, lectin-Like ox-LDL receptor-1 (LOX-1), play important roles in the development of endothelial injuries. Olmesartan can protect endothelial cells from the impairment caused by various pathological stimulations. In the present study we investigated whether olmesartan decreased the impairment of endothelial cells induced by ox-LDL by exerting its effects on LOX-1 both in vitro and in vivo. Incubation of cultured endothelial cells of neonatal rats with ox-LDL for 24 h or infusion of ox-LDL in mice for 3 weeks led to the remarkable impairment of endothelial cells, including increased lactate dehydrogenase synthesis, phosphorylation of p38 mitogen-activated protein kinases (p38 MAPK) and expression of apoptotic genes such as B-cell leukemia/lymphoma 2 (Bcl-2)-associated X protein (Bax) and caspase-3. Simultaneously, the cell vitality and expression of Bcl-2 gene were greatly reduced. All these effects, however, were significantly suppressed by the treatment with olmesartan. Furthermore, ox-LDL promoted up-regulation of LOX-1 expression either in cultured endothelial cells or in the aortas of mice, which was reversed with the administration of olmesartan. Our data indicated that olmesartan may attenuate the impairment of endothelial cell via down-regulation of the increased LOX-1 expression induced by ox-LDL.
Prediction of True Circulatory Decompensation in Chronic Heart Failure for Optimal Timing of Mechanical Circulatory Support: Non-Invasive Arterial-Ventricular Coupling
Authors: Siniawski Henryk , Lehmkuhl Hans , Dandel Michael , Unbehaun Axel , Kemper Dagmar , Weng Yuguo , Hetzer Roland
Published: February 2012

Background: Prospective comparative studies to predict the risk of hemodynamic deterioration in patients referred for transplantation were performed on the basis of standard invasive and non-invasive data and new wave intensity (WI) parameters. Methods and results: Study Group 1 consisted of 151 consecutive outpatients (age 48.7 ± 12 years; 110 men) with end-stage dilative cardiomyopathy. Group 2, consisting of 11 consecutive patients (age 50 ± 11 years; 6 men) with sinus rhythm and “true” decompensation, was used to create “critical values” of WI. There were no demographic or somatic (weight and height) differences between the groups. The follow-up period of ambulatory patients was 31 ± 8 months. Non-invasive WI was studied in the common carotid artery. Complete invasive and non-invasive data were also recorded on the day of investigation. During follow-up 44 pts were lost; there were 15 cardiac deaths (10%), life-saving ventricular assist device implantation in 10 (6.6%) and transplantation in 19 (12.7%). For statistical purposes this group was named the “events” Group B (n = 44). A predisposing factor for events (death, “true” decompensation and “urgent” transplantation in ambulatory patients) was low first peak (“cut-off value” assessed in Group 2 < 4100 mmHg*s³) (OR 45.6, CI 14.5–143.3, p < 0.001). Less powerful predictors of the risk of deterioration were pulmonary capillary pressure (PCP), diastolic pulmonary artery pressure (PAP) and E/A mitral wave relation (p = 0.05). Conclusions: The new ventricular-arterial coupling parameter 1st peak of WI can potentially be used to distinguish patients at high risk for true deterioration and death. This parameter can be used to predict the need for assist device implantation.
A Discrete Wavelet Transform (DWT)-Based Energy-Efficient Selective Retransmission Mechanism for Wireless Image Sensor Networks
Authors: Costa Daniel G. , Guedes Luiz Affonso
Published: February 2012

Source nodes in wireless image sensor networks transmit much more information than traditional scalar sensor networks, thereby demanding more energy of intermediate relaying nodes and putting energy efficiency as a key design issue. Intermediate nodes are usually interconnected by error-prone links where bit-errors are common, potentially degrading the application monitoring quality. When reliability is assured by retransmission mechanisms, higher packet error rates do not affect the application quality but result in additional energy consumption due to packet retransmission, even though many monitoring applications can tolerate some loss in the quality of the received image. DWT coding can decompose an image in data subbands, each one with different relevancies for the reconstruction of the original image at the receiver side. We propose an energy-efficient selective hop-by-hop retransmission mechanism where the reliability level of each packet is a function of the relevance of the payload data, according to the resulting subbands and the number of times a 2D DWT is applied over the images captured by the sensors’ cameras. In so doing, some lost packets are not retransmitted, saving energy of intermediate nodes with low impact to the quality of the reconstructed images. In order to estimate the benefits of this tradeoff between energy consumption and image quality, we designed a comprehensive energy consumption model and applied it in extensive mathematic simulations, providing substantial information about the mean performance of the proposed approach when compared with a fully-reliable transmission mechanism.
Arbitrary Super Surface Modes Bounded by Multilayered Metametal
Authors: Yang Ruoxi , Huang Xiaoyue , Lu Zhaolin
Published: February 2012

The dispersion of the fundamental super mode confined along the boundary between a multilayer metal-insulator (MMI) stack and a dielectric coating is theoretically analyzed and compared to the dispersion of surface waves on a single metal-insulator (MI) boundary. Based on the classical Kretschmann setup, the MMI system is experimentally tested as an anisotropic material to exhibit plasmonic behavior and a candidate of “metametal” to engineer the preset surface plasmon frequency of conventional metals for optical sensing applications. The conditions to obtain artificial surface plasmon frequency are thoroughly studied, and the tuning of surface plasmon frequency is verified by electromagnetic modeling and experiments. The design rules drawn in this paper would bring important insights into applications such as optical lithography, nano-sensing and imaging.
Polyamidoamine Dendrimer Conjugates with Cyclodextrins as Novel Carriers for DNA, shRNA and siRNA
Authors: Arima Hidetoshi , Motoyama Keiichi , Higashi Taishi
Published: February 2012

Gene, short hairpin RNA (shRNA) and small interfering RNA (siRNA) delivery can be particularly used for the treatment of diseases by the entry of genetic materials mammalian cells either to express new proteins or to suppress the expression of proteins, respectively. Polyamidoamine (PAMAM) StarburstTM dendrimers are used as non-viral vectors (carriers) for gene, shRNA and siRNA delivery. Recently, multifunctional PAMAM dendrimers can be used for the wide range of biomedical applications including intracellular delivery of genes and nucleic acid drugs. In this context, this review paper provides the recent findings on PAMAM dendrimer conjugates with cyclodextrins (CyDs) for gene, shRNA and siRNA delivery.
Effects of Emulsion-Based Resonant Infrared Matrix Assisted Pulsed Laser Evaporation (RIR-MAPLE) on the Molecular Weight of Polymers
Authors: McCormick Ryan D. , Lenhardt Jeremy , Stiff-Roberts Adrienne D.
Published: February 2012

The molecular weight of a polymer determines key optoelectronic device characteristics, such as internal morphology and charge transport. Therefore, it is important to ensure that polymer deposition techniques do not significantly alter the native polymer molecular weight. This work addresses polymers deposited by resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE). By using a novel emulsion-based target technique, the deposition of smooth, contiguous films with no evidence of chemical degradation have been enabled. However, structural degradation via a reduction in molecular weight remains an open question. The common polymer standard, PMMA, and the optoelectronic polymers, P3HT and MEH-PPV, have been characterized before and after emulsion-based RIR-MAPLE deposition via gel permeation chromatography to determine if RIR-MAPLE affects the deposited polymer molecular weight. Proton nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy measurements have also been conducted to verify the absence of chemical degradation. These measurements verify that there is no chemical degradation of the polymers, and that PMMA and P3HT show no structural degradation, but MEH-PPV exhibits a halving of the weight-averaged molecular weight after RIR-MAPLE deposition. Compared with competing laser deposition techniques, RIR-MAPLE is shown to have the least effect on the molecular weight of the resulting thin films.
An Electronic Nose Based on Coated Piezoelectric Quartz Crystals to Certify Ewes’ Cheese and to Discriminate between Cheese Varieties
Authors: Pais Vânia F. , Oliveira João A. B. P. , Gomes Maria Teresa S. R.
Published: February 2012

An electronic nose based on coated piezoelectric quartz crystals was used to distinguish cheese made from ewes’ milk, and to distinguish cheese varieties. Two sensors coated with Nafion and Carbowax could certify half the ewes’ cheese samples, exclude 32 cheeses made from cow’s milk and to classify half of the ewes’ cheese samples as possibly authentic. Two other sensors, coated with polyvinylpyrrolidone and triethanolamine clearly distinguished between Flamengo, Brie, Gruyère and Mozzarella cheeses. Brie cheeses were further separated according to their origin, and Mozzarella grated cheese also appeared clearly separated from non-grated Mozzarella.
Synthesized Population Databases: A Geospatial Database of US Poultry Farms
Authors: Bruhn Mark , Munoz Breda , Cajka James , Smith Gary , Curry Ross , Wagener Diane , Wheaton William
Published: February 2012

Because they can spread to humans, infections and diseases in poultry and other livestock populations are of keen interest to public health officials. Officials need to plan for a rapid response, and to do so, they need information about where farms are located and how they cluster spatially. No public domain, nationwide database currently exists for actual farm locations. RTI researchers in coordination with University of Pennsylvania infectious disease modelers developed a new way to create a synthetic dataset that replicates the spatial distribution of poultry farms and the type and number of birds raised on them. The RTI method produced a more realistic dataset than the currently used random placement alternative. The results suggest the RTI method could be used to simulate other livestock farms of interest to infectious disease researchers.
Antiviral Effect of Maraviroc in Semen: A Case Report
Authors: Pasquier Christophe , Moinard Nathalie , Sauné Karine , Daudin Myriam , Trancart Stéphanie , Massip Patrice , Izopet Jacques , Bujan Louis
Published: February 2012

We describe the antiviral effect of maraviroc in a patient who had been shedding high levels of HIV-1 in seminal fluid for three years despite an undetectable blood plasma viral load. Adding maraviroc to HAART stopped the seminal shedding. We discuss the mechanisms involved and the effect on sexual transmission.
The Ultrasound Imaging Module: A Report from the GRAPPA 2010 Annual Meeting
Authors: KAELEY GURJIT S. , BAKEWELL CATHERINE J.
Published: February 2012

In a plenary session at the 2010 meeting of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), the use of sonography for evaluating articular disease and enthesitis in psoriasis and psoriatic arthritis (PsA) was reviewed. Ultrasound can readily demonstrate signs of synovitis, erosions, and osteoproliferation. There is a need to develop ultrasound joint indices to evaluate and follow PsA longitudinally. Sonography is able to depict ultrastructural features of enthesitis, as well as increased vascularity. Sonographic signs of subclinical enthesitis in patients with psoriasis have been reported by 2 groups, 1 of which has reported limited longitudinal data that suggest baseline composite enthesitis scores may predict future risk of PsA. Although recent studies have studied mostly lower extremity entheses, further work is needed to clarify if other areas need to be included, especially within the framework of the synovial entheseal complex. The study design of the PREPARE (Prevalence of Psoriatic Arthritis in Adults with Psoriasis) trial was also presented.
Psoriasis and Psoriatic Arthritis Video Project: An Update from the 2010 GRAPPA Annual Meeting
Authors: WOODCOCK JAMIE L. , MEASE PHILIP J. , CALLIS DUFFIN KRISTINA
Published: February 2012

Changes in severity of psoriasis and psoriatic arthritis (PsA) are assessed in clinical trials by a variety of physical examination instruments. At the 2010 annual meeting of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), members were updated on the development and availability of modules that teach these instruments. Web-based interactive multimedia presentations for psoriasis assessments have been completed, including modules for Psoriasis Area and Severity Index and Body Surface Area, 5-point and 6-point Physician Global Assessment, the original and modified Nail Psoriasis Severity Index, the Palmar-Plantar Pustular Psoriasis Area and Severity Index, and the Psoriasis Scalp Severity Index. Rheumatology modules will include assessment of tender and swollen joints, and evaluations of enthesitis, dactylitis, and axial disease. Each module will include the background and rationale for each tool, demonstration video of each examination, diagrams and photographs to emphasize teaching points, and an optional examination at the end. The rheumatology modules have been recorded but were not yet available for review at the meeting. The dermatology modules are currently in use by pharmaceutical and biotechnology companies engaged in research on treatments for psoriasis and PsA. The next phase of this project includes analysis of interobserver reliability, translation into languages other than English for international users, and other proposed studies.
Genetics of Psoriasis and Psoriatic Arthritis: A Report from the GRAPPA 2010 Annual Meeting: Figure 1.
Authors: RAHMAN PROTON , ELDER JAMES T.
Published: February 2012

Psoriasis vulgaris (PsV) and psoriatic arthritis (PsA) are interrelated disorders, PsA representing a disease within a disease. From an epidemiological perspective, the genetic contributions of PsV and PsA are now well documented. HLA-C is firmly established as a PsV/PsA gene, with HLA-Cw*0602 as a major risk allele. Fine-mapping studies within the MHC region in PsV and PsA have identified novel loci that are independent of the HLA-Cw6 allele. Recent genome-wide association scans have led to a substantial increase in the number of candidate genes reaching genome-wide significance in PsV and PsA cohorts. Most of these genes can be grouped into an integrated pathogenic model of PsV/psoriatic disease comprising distinct signaling networks affecting skin barrier function (LCE3, DEFB4, GJB2), innate immune responses involving nuclear factor-κB and interferon signaling (TNFAIP3, TNIP1, NFKBIA, REL, FBXL19, TYK2, NOS2), and adaptive immune responses involving CD8 T lymphocytes and interleukin 23 (IL-23)/IL-17-mediated lymphocyte signaling (HLA-C, IL12B, IL23R, IL23A, TRAF3IP2, ERAP1). Further development of a global genetic risk score and inclusion of potential gene/gene and gene/environment interactions will likely enhance the predictive value of recently identified genetic variants.
The Path Forward to Biomarker Discovery in Psoriatic Disease: A Report from the GRAPPA 2010 Annual Meeting
Authors: GLADMAN DAFNA D. , RITCHLIN CHRISTOPHER T. , FITZGERALD OLIVER
Published: February 2012

At the 2010 annual meeting of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), wide-ranging discussions were held regarding biomarker research in psoriatic disease. Consensus was reached on 2 areas of priority: (1) the study of soluble biomarkers of radiographic progression in psoriatic arthritis (PsA); and (2) the analysis of comorbidity biomarkers, specifically cardiovascular and articular, in a psoriasis inception cohort. For each of these areas, rigorous definition of the clinical phenotype of PsA will be essential. To date, 2 instruments have been identified to define the phenotype: the ClASsification of Psoriatic ARthritis criteria and various screening questionnaires. In this overview, we discuss the challenges of the clinical phenotype of PsA and review GRAPPA plans for developing a research program for biomarker discovery.
Comorbidities of Psoriatic Arthritis — Metabolic Syndrome and Prevention: A Report from the GRAPPA 2010 Annual Meeting
Authors: RAYCHAUDHURI SIBA P.
Published: February 2012

Psoriatic arthritis (PsA) is associated with serious comorbidities such as increased cardiovascular risk, hypertension, depression, and reduced quality of life. Patients with psoriasis have been observed to have an increased incidence of metabolic syndrome compared with the general population; recently, this has also been observed in patients with PsA. This review focuses on the comorbidities associated with PsA, with an emphasis on risks of coronary artery disease and metabolic syndrome. We also discuss the development of a comprehensive approach for the management of comorbidities of PsA. The review summarizes a presentation at the 2010 annual meeting of GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis).
Introduction : qualité, évaluation, européanisation et gouvernance de l'éducation
Authors: Grek Sotiria , Lawn Martin , Ozga Jenny
Published: February 2012

Résumé Ce dossier porte sur la production incessante de données pour suivre la qualité et la performance de l’éducation en Europe et sur leur interprétation en termes de gouvernance. Les contributeurs examinent dans quelle mesure ces données et le souci de l’assurance qualité et de l’évaluation qu’elles traduisent peuvent être lus comme une forme de fabrication, voire de gouvernance de l’éducation européenne. Ils s’appuient sur une recherche collaborative (2006-2009, Angleterre, Danemark, Finlande, Écosse et Suède) analysant la façon dont les données de performance ont changé la gouvernance et le contrôle de l’éducation. Au-delà des données sur l’assurance-qualité et ses effets, la création d’un espace politique européen de l’éducation est au cœur du dossier. Le débat porte sur la façon dont les stratégies nationales encouragent ou non un processus d’européanisation et fabriquent ainsi un espace politique européen de l’éducation gouverné par les données, ce terme de fabrication incluant l’idée de tromperie face aux preuves... L’ambition ici est double : analyser l’européanisation de l’éducation, souvent négligée ; adopter une perspective critique sur la manière dont les données fabriquent un système et un espace partagé d’éducation européens susceptibles de présenter une image simplifiée, voire déformée, du monde ; ce qui souligne l’importance de donner du sens à la traduction des imaginaires en opérations/pratiques et en institutions.
Croissance agricole et sortie de pauvreté : que nous apprennent les trajectoires des ménages ruraux en Indonésie ?
Authors: Bourgeois Robin , Meuriot Véronique
Published: February 2012

L’existence d’un déterminisme de la croissance de la production agricole sur la sortie de pauvreté des ménages ruraux reste incertaine. L’hypothèse d’une telle relation est testée sur un panel de ménages agricoles indonésiens enquêté en 2001 et 2006. L’étude des trajectoires de statu quo , sortie, et entrée en pauvreté montre que la croissance agricole est une condition ni nécessaire, ni suffisante pour sortir de la pauvreté mais offre une certaine protection contre l’appauvrissement. Les activités non agricoles expliquent les différentes trajectoires. Cela signifie que la lutte contre la pauvreté en milieu rural n’est pas une simple affaire de productivité agricole.
La simulation d'un marché comme outil pédagogique et de recherche en négociation
Authors: Sohier Joël , Cottet Patrice , Mbengue Ababacar , Sohier Sylvie
Published: February 2012

Résumé L’enseignement de la négociation a donné lieu à une grande créativité en matière d’outils pédagogiques de mise en situation des étudiants. Ces outils pédagogiques qui cherchent à créer des contextes proches de la réalité, ont été exploités par une recherche qui peine à trouver des observations issues de situations réelles de négociation. Cet article montre le processus de co-construction entre la recherche et la pédagogie. Il décrit comment l’approche dyadique a servi à créer un outil pédagogique qui lui-même ouvre des perspectives nouvelles pour la recherche sur la négociation.
Le capital culturel et la communauté virtuelle
Authors: Choi Hang-sub
Published: February 2012

Résumé Cet article a pour objectif de comprendre pourquoi les classes moyennes dans la société coréenne poursuivent le style de vie des classes supérieures et comment elles se servent de la communauté virtuelle pour le faire. Fondée sur le principe de l’échange non marchand, celle-ci sert dans une certaine mesure à la redistribution du capital culturel vers ceux qui n’en bénéficient pas au même niveau que la bourgeoisie. Si Pierre Bourdieu, pour sa part, avait plus spécifiquement insisté sur la nécessité de critiquer la stratégie « clandestine » menée par la classe dominante à travers la manipulation de son capital culturel, il n’a cependant pas saisi les activités de partage des goûts existant entre les différentes classes sociales sur lesquelles a plus particulièrement insisté Michel Maffesoli.
Preparation and Properties of Biodegradable Film Composites Using Modified Cellulose Fibre-Reinforced with PVA
Authors: Laxmeshwar Sandeep S. , Madhu Kumar D. J. , Viveka S. , Nagaraja G. K.
Published: January 2012

Cellulose has a potential to become a key resource in the development of biodegradable film composites. In this work, cellulose was modified by using 2-(Trifluromethyl)benzoylchloride by base-catalyzed reaction. Modification of cellulose was confirmed by IR studies. The biodegradable composite films were developed by film casting method using modified cellulose with Poly(vinyl alcohol) in different compositions. The film composites were characterized by mechanical, moisture absorption, gas barrier, and biodegradable properties. Obtained films have shown transparency and flexibility and displayed good mechanical properties. Film composites also showed good biodegradability. Better barrier properties showed by film composites as the percentage of modified cellulose increased. This indicates the importance of modified cellulose as a reinforcing agent. After evaluating these properties of film composites, we came to conclusion that these biocomposites can be used to membrane and packaging applications.
Towards Universal Screening for Colon Cancer: A Cheap, Reliable, Noninvasive Test Using Gene Expression Analysis of Rectal Swabs
Authors: Smith Andrew P. , Chiu Yanek S. Y. , Lee Nancy M.
Published: January 2012

Though colon cancer is the second leading cause of cancer deaths in the US, it is entirely preventable through early screening to detect and remove adenomatous polyps. Colonoscopy has long been regarded as the “gold standard” but is expensive, invasive, and uncomfortable, and only about half those considered at risk for colon cancer currently submit to colonoscopy or to less reliable alternatives such as fecal occult blood test. Here we describe the use of gene expression analysis to detect altered expression of certain genes associated with not only colon cancer but also polyps. The analysis can be performed on rectal swabs, with specimens provided in a routine doctor's office visit. The existence of this cheap and simple test, together with an active program to encourage individuals to submit to screening, could help eradicate colon cancer.
Microstructures and Mechanical Properties of Hot-Pressed -Matrix Composites Reinforced with SiC and Particles
Authors: Zhou Hongming , Li Jian , Yi Danqing
Published: January 2012

-matrix composites reinforced with and SiC particles were fabricated by means of wet-mixing and heat-pressing process. Scanning electron microscope (SEM), X-ray diffractometry (XRD), polarizing microscopy, Vickers hardness tester, with a universal materials testing machine were used to investigate the morphology, grain size, hardness, fracture toughness, and bending strength of the synthesized composites. Notable effects on the bending strength and fracture toughness of caused by the addition of SiC and particles were found. The composite with 20 vol.% SiC and 20 vol.% Si3N4 particles has the highest strength and toughness, which is about 100% and 340%, respectively, higher than that of pure . The grain size of decreases gradually with the volume content of SiC and particles increasing from 0% to 40%, and -20 vol% SiC-20 vol% Si3N4 composite exhibits the minimum grain size of . The relationship between the grain size of and bending strength is not entirely fit with Hall-Petch equation. The strengthening mechanisms of the composite include fine-grain strengthening and dispersion strengthening. The toughening mechanisms of the composite include fine grain, microcracking, crack deflection, crack microbridging, and crack branching.
Detection of Node Failure in Wireless Image Sensor Networks
Authors: Mahapatro Arunanshu , Khilar Pabitra Mohan
Published: January 2012

A sequenced process of fault detection followed by dissemination of decision made at each node characterizes the sustained operations of a fault-tolerant wireless image sensor network (WISN). This paper presents a distributed self-fault diagnosis model for WISN where fault diagnosis is achieved by disseminating decision made at each node. Architecture of fault-tolerant wireless image sensor nodes is presented. Simulation results show that sensor nodes with hard and soft faults are identified with high accuracy for a wide range of fault rate. Both time and message complexity of the proposed algorithm are for an -node WISN.
T4 and T6 Treatment of 6061 Al-15 Vol. % SiCP Composite
Authors: Rajasekaran S. , Udayashankar N. K. , Nayak Jagannath
Published: January 2012

Aging temperature history has profound effect on the mechanical and corrosion behavior of 6061 Al/SiC composite. In order to understand the effect of aging on the corrosion resistance, the natural and artificial aging behavior of 15 vol. % 6061 Al-SiCP composites was studied using the aging treatment and the Brinell hardness measurements. The aging curves for the composite (T6 treated) were determined at various aging temperatures such as room temperature, 140, 160, 180, 200, 220, and 240°C. According to the peak hardness variation with temperature profile, it is found that the composite is underaged at 140°C and 160°C. Peak aging takes place at 180°C. Overaging takes place at 200°C, 220°C, and 240°C. The natural aging characteristics of the composite (T4 treated) are also studied using the Brinell hardness measurements.
Polyetheretherketone Cages Alone with Allograft for Three-Level Anterior Cervical Fusion
Authors: Liu Hong , Ploumis Avraam , Li Chunde , Yi Xiaodong , Li Hong
Published: February 2012

A total of 25 consecutive patients suffering from degenerative cervical disc disease who underwent three-level anterior cervical discectomy and fusion (ACDF) including polyetheretherketone (PEEK) cages packed with allograft were followed up for at least two years. The fusion rate reached 72% (18/25), and asymptomatic pseudarthrosis was seen in 6 patients but without mobility on flexion-extension radiographs, and revision surgery was not needed. Cage subsidence occurred at one level (C67), but it was not progressive, and reoperation was not necessary. A significant increase (P<0.001) in fused segment angle (FSA) and fused segment height (FSH) was observed postoperatively. Similarly, a significant clinical improvement (P<0.001) was demonstrated postoperatively in terms of Japanese Orthopedic Association (JOA) score and visual analog scales (VASs) score. PEEK cages alone with allograft proved to be a safe and effective surgical option in the treatment of three-level degenerative cervical disc disease. Although the fusion rate was not high, this technique may offer improvement of symptomatology and maintenance of cervical spine's sagittal profile.
Some Remarks on the Sumudu and Laplace Transforms and Applications to Differential Equations
Authors: Kiliçman Adem , Eltayeb Hassan
Published: February 2012

We study the relationship between Sumudu and Laplace transforms and further make some comparison on the solutions. We provide some counterexamples where if the solution of differential equations exists by Laplace transform, the solution does not necessarily exist by using the Sumudu transform; however, the examples indicate that if the solution of differential equation by Sumudu transform exists then the solution necessarily exists by Laplace transform.
A Study on the Performance of a Magnetic-Fluid-Based Hydrodynamic Short Journal Bearing
Authors: Patel N. S. , Vakharia D. P. , Deheri G. M.
Published: January 2012

Efforts have been made to study and analyze the performance of a hydrodynamic short journal bearing under the presence of a magnetic fluid lubricant. With the usual assumptions of hydrodynamic lubrication, the associated Reynolds equation for the fluid pressure is solved with appropriate boundary conditions. In turn, this is then used to calculate the load-carrying capacity which results in the calculation of friction. The computed results presented in graphical form suggest that the bearing system registers an improved performance owing to the magnetic fluid as compared to the conventional lubricant. It is clearly observed that the load-carrying capacity increases nominally while the coefficient of friction decreases significantly. Besides, it is seen that the bearing can support a load even when there is no flow of lubricant. In addition, this type of study may offer an additional degree of freedom from design point of view in terms of the forms of the magnitude of the magnetic fluid.
Validation of an XCT/fDOT System on Mice
Authors: Koenig Anne , Planat-Chrétien Anne , Hassler Kai , Bucher Martina , Coutard Jean-Guillaume , Hervé Lionel , Brambilla Marco , Josserand Véronique , Coll Jean-Luc , Vats Divya , Dikaiou Katerina , Rudin Markus , Dinten Jean-Marc
Published: January 2012

In this paper we present systems for dual modality imaging, combining fluorescence-enhanced diffuse optical tomography and X-ray computed tomography. Fluorescence diffuse optical tomography is carried out in a cylindrical geometry, which ensures optimal sampling and a straight forward integration with the X-ray modality. Specific acquisition protocols and reconstruction software have been developed to this end. The X-ray computed tomography serves two purposes. First, it provides the anatomical information in the registered dual modality images. Second, it provides the actual shape and boundaries of the animal as a priori input to the fluorescence reconstruction algorithm. To evaluate the performance of the optical imaging system, experiments have been conducted on phantoms, mice with inserted fluorescing capillaries, and finally on mice bearing tumors, ex-vivo and in-vivo. Experiments on mice with capillaries inserted in different region of interest, allow estimating the detection limits of fluorophore concentrations. The fluorescence reconstructions are shown to be geometrically consistent with the X-ray images. Finally we demonstrate the capability of the bimodal system to localize real tumours in mice in-vivo. These results show that dual modality fluorescence-enhanced diffuse optical tomography and X-ray computed tomography imaging in cylindrical geometry has a high potential for small animal tumour evolution studies.
Oxalate Content of Stir Fried Silver Beet Leaves (Beta Vulgaris Var. Cicla) with and without Additions of Yoghurt
Authors: Teo Evelyn , Savage Geoffrey
Published: February 2012

Total and soluble oxalic acids were extracted and analysed by HPLC chromatography following Asian cooking methods, which involved soaking, boiling and stir frying of silver beet (Beta vulgaris var. cicla) leaves. Autumn-grown silver beet leaves contained 1658 ± 114 mg/100 g dry matter (DM) of total oxalates, 954 ± 49 mg/100 g DM of soluble oxalates and 704 ± 98 mg/ 100 g DM insoluble oxalates. Soaking and boiling before stir frying reduced the soluble oxalate contents to a mean of 455 mg/100 g DM. Addition of standard or low fat yoghurt following the pre-treatments of soaking, boiling, stir frying and soaking, boiling and stir frying further reduced the soluble oxalate content to a mean of 190.8 ± 49.8 and 227.5. ± 47.0, respectively, for the standard and low fat yoghurt mixes.
Mixing Properties and Gluten Yield of Dough Enriched with Pea Protein Isolates
Authors: Mercier Samuel , Villeneuve Sébastien , Mondor Martin , Drolet Hélène , Ippersiel Denis , Lamarche François , Marchais Louis-Philippe Des
Published: February 2012

Over the last few years, many studies were carried out on the use of legume-based ingredients to supplement cereal-based matrices and produce nutritionally enhanced products. However, little is known about the influence of supplementation on the mixing properties of the enriched cereal-based matrices. The objective of this work was to study the impact of supplementing cereal-based matrices with commercial pea protein isolate or pea protein isolate produced by ultrafiltration/diafiltration using a 50 kDa membrane on the dough mixing properties. Studies were performed using a PertenÒ Glutomatic to estimate gluten yield, namely in terms of gluten index, wet gluten, dry gluten and water binding capacity, and using a BrabenderÒ Farinograph to estimate water absorption, dough development time, stability, mixing tolerance index and minimum and maximum water content for dough formation. Four levels of pea protein isolate enrichment were considered: 0, 5, 10 and 15%. Results indicated that level of enrichment has little effect on measured mixing properties compared to the pea protein isolates considered. Isolate processed by membrane technologies takes part to the dough formation which does not seem to be the case with commercial isolate. Higher amount of water is required for dough formation with matrices enriched with commercial pea isolate compared to membrane processed isolate, while stronger dough properties are observed for matrices enriched with membrane processed isolate. This is attributable to the properties of the isolate, namely solubility and state of the proteins (native or denatured), which could impact how they interact with wheat proteins.
Evaluation of Surface Enhanced Raman Spectroscopy (SERS) for Detection of Acetone in the Context of Food Safety and Quality Application
Authors: Mohapatra Punyatoya , Panigrahi Suranjan
Published: February 2012

Development of sensors for detection of contaminated food products is important to ensure safety of the community. This paper focuses on detection of a compound, acetone associated with pathogen contamination and spoilage of beef in packaged condition. Surface Enhanced Raman Spectroscopy (SERS) technique was used to develop an integrated sensing system. This sensing system utilized laboratory prepared silver sol as the SERS substrate to detect acetone at low ppm and high ppb concentration. A set of eight experiments with two different experimental conditions were conducted. The first four set provided an estimated lower detection limit (LDL) ranging between 69.63 ppm and 630.17 ppm corresponding to the 1711 cm-1 and 532 cm-1 Raman shift (cm-1) regions, respectively. The second four sets of experiments provided a lower estimated LDL ranging between 9.78 ppm and 43.45 ppm corresponding to 1222 cm-1 and 532 cm-1, respectively. This study demonstrated the ability of this sensing system to detect the indicator compound.
AS CONQUISTAS NA LEGISLAÇÃO DO DIREITO À EDUCAÇÃO DAS CRIANÇAS PEQUENAS À EDUCAÇÃO E OS DESAFIOS PARA SUA EFETIVAÇÃO
Authors: Sabia Claudia Pereira de Pádua
Published: February 2012

This article presents a brief historical review of early childhood Education in Brazil with their latest developments. It is noteworthy achievements in legislation. Adresses the challenges to be overcome for the expansion and quality. In the face of limited funding and teacher’formation required to this schooling level uses the methodology of the bibliographic research. We end by pointing out that children education policies adopted in Brazil have arose new process of social exclusion.
Performance of poly(ethylene‐co‐vinyl acetate) nanocomposites using distinct clays
Authors: Pistor Vinicios , Ornaghi Heitor Luiz , Ferreira Carlos Arthur , Zattera Ademir José
Published: January 2012

This study aimed to evaluate the performance of EVA nanocomposites with distinct clays. Three different types of nanoclays were used (Na+, 15A, and 30B) at a processing speed of 400 rpm. By DMA, an increase in the storage and loss moduli was found, as well as lower peak height and peak width at half‐height for the nanocomposites containing 15A clay. Also, in rheometry analysis, higher moduli values were obtained for the 15A clay nanocomposite. The relaxation and retardation spectra showed three distinct peaks for the nanocomposites containing the organophilic clays. Finally, the XRD and TEM analysis showed a microcomposite formation, intercalated and exfoliated structure for the Na+, 15A, and 30B nanocomposites, respectively. These results possibility a greater understanding of the interaction effects between the intercalated (15A) and exfoliated (30B) clays and the influence of the type of modifier in the nanocomposites studied. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation of iminodiacetic acid‐type composite chelating material IDAA‐PGMA/SiO2 and preliminary studies on adsorption behavior of heavy metal ions and rare earth ions
Authors: Gao Baojiao , Jiang Guiming , An Fuqiang
Published: January 2012

A kind of iminodiacetic acid (IDAA)‐type composite chelating materials was prepared by first graft polymerization and subsequent polymer reaction. Monomer glycidyl methacrylate (GMA) was grafted on micron‐sized silica gel particles in the manner of “graft through” in a solution polymerization system, resulting in the grafted particles poly(glycidyl methacrylate) (PGMA)/silicon dioxide (SiO2). Subsequently, the ring‐opening reaction of the epoxy groups of the grafted PGMA was carried out with IDAA as reaction reagent, resulting in the bonding of IDAA groups onto PGMA/SiO2 and obtaining the composite chelating material IDAA‐PGMA/SiO2 particles. The effects of the main factors on the graft polymerization of GMA and the bonding reaction of IDAA were examined emphatically, and the adsorption behavior of IDAA‐PGMA/SiO2 particles toward several kinds of heavy metal ions and rare earth ions was preliminarily explored. The experiments results show that: (a) to obtain the grafted particles PGMA/SiO2 with high grafting degree, in the graft polymerization step, the reaction temperature and the used amount of initiator should be controlled. The suitable temperature is 70°C and the appropriate used amount of initiator is 1.4 % of the monomer mass. Under the optimal conditions, the grafted degree of PGMA can reach 17.50 g/100 g. (b) It is feasible to introducing of IDAA groups onto PGMA/SiO2 particles via ring‐opening reaction of epoxy groups of the grafted PGMA under alkaline conditions, and the bonding rate of IDAA group can get up to 70% based on epoxy groups of the grafted PGMA. (c)The composite chelating material IDAA‐PGMA/SiO2 possesses very strong chelating adsorption ability for heavy metal ions, and especially toward Pb2+ ion, the adsorption capacity can reach 24 g/100 g. (d) The adsorption ability of IDAA‐PGMA/SiO2 for rare earth ions is weaker than that for heavy metal ions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012