bluuebunny/crossref_metadata_2025_split huggingface dataset:
Small size‐specific umbilical vein diameter in severe growth restricted fetuses that die in utero
Authors: Rigano Serena , Bozzo Maddalena , Padoan Alessandra , Mustoni Paola , Bellotti Maria , Galan Henry L. , Ferrazzi Enrico 
Published: September 2008

AbstractBackgroundTo study changes in umbilical vein (UV) blood flow velocity, diameter and blood flow volume in intrauterine growth retardation (IUGR) fetuses who die in utero (IUD‐IUGR).MethodsTwelve singleton IUGR fetuses who died in utero below 600 g were included. All cases had abnormal uterine and umbilical arteries PI. UV diameter and velocity were measured at the time of diagnosis, and at the last exam, within 24 hours prior to intrauterine death. UV flow was calculated per unit weight (mL/min/kg) and abdominal circumference (AC) (mL/min/cm). UV diameter and velocity were normalized per unit AC. Findings were compared to 14 severe viable‐IUGR and 22 normal gestational age‐matched fetuses.ResultsUV flow (mL/min/kg) was significantly lower in IUD‐IUGR compared to viable‐IUGR (87 ± 30 mL/min/kg) and control fetuses (131 ± 33 mL/min/kg) both at the first (79 ± 40 mL/min/kg) (P < 0.0001), and at the last exam (54 ± 29 mL/min/kg) (P < 0.0001). No significant longitudinal flow changes were observed. UV velocity/AC was significantly reduced both in IUD‐IUGR and viable‐IUGR compared to normal fetuses. UV diameter/AC, was significantly reduced only in IUD‐IUGR and not in viable‐IUGR compared to normal fetuses.ConclusionsUV flow (mL/min/kg) was significantly lower in IUD‐IUGR fetuses both versus viable‐IUGR and normal fetuses. A low flow was due to a decreased UV flow velocity, but also due to a reduced vessel size. This significantly smaller UV size observed in IUGR fetuses with the worst outcome could be considered a severe prognostic sign because of the diagnosis of severe growth restriction. Copyright © 2008 John Wiley & Sons, Ltd.
Fifteen years of triple tests in The Netherlands; the life cycle of a screening test
Authors: Wortelboer E. J. , Koster M. P. H. , Stoutenbeek Ph. , Loeber J. G. , Visser G. H. A. , Schielen P. C. J. I. 
Published: September 2008

AbstractObjectiveThis report provides an overview of 15 years prenatal screening for Down syndrome (DS).MethodsBetween 1991 and 2005, blood samples for the triple test were sent for analysis to our laboratory. Test results were considered screen‐positive for neural tube defects (NTDs) if the serum alpha‐1‐fetoprotein ≥ 2.50 MoM for singleton pregnancies or screen‐positive for DS if the calculated risk was at least 1 in 250.ResultsAs many as 42 554 tests were performed. Data on the pregnancy outcome were available for 30 290 screening tests (71.2%). In 1991, most requests (93%) came from the university hospitals; thereafter a shift toward midwives occurred. Until 2001, the number of requests rose to 3500 a year. Most samples were collected between 15 and 17 weeks of gestation. The median age of women for whom a test was requested increased from 30.5 to 34.5. The detection rate (DR) for DS remained stable over the years (80%), with a false positive rate of about 13%. The DR for Trisomy 13, 18, and NTD was 50, 68, and 70%, respectively.ConclusionBased on the results of this study, the triple test may be considered a fairly good second trimester screening test. Here it is shown that health practitioners got more acquainted with the test through the years. This may have served the swift introduction of a formal national screening program that started in January 2007. Copyright © 2008 John Wiley & Sons, Ltd.
An evaluation of a data mining signal for amyotrophic lateral sclerosis and statins detected in FDA's spontaneous adverse event reporting system
Authors: Colman Eric , Szarfman Ana , Wyeth Jo , Mosholder Andrew , Jillapalli Devanand , Levine Jonathan , Avigan Mark 
Published: September 2008

AbstractBackgroundWe detected disproportionate reporting of amyotrophic lateral sclerosis (ALS) with HMG‐CoA‐reductase inhibitors (statins) in the Food and Drug Administration's (FDA) spontaneous adverse event (AE) reporting system (AERS).PurposeTo describe the original ALS signal and to provide additional context for interpreting the signal by conducting retrospective analyses of data from long‐term, placebo‐controlled clinical trials of statins.MethodsThe ALS signal was detected using the multi‐item gamma Poisson shrinker (MGPS) algorithm. All AERS cases of ALS reported in association with use of a statin were individually reviewed by two FDA neurologists. Manufacturers of lovastatin, pravastatin, simvastatin, fluvastatin, atorvastatin, cerivastatin, and rosuvastatin were requested to provide the number of cases of ALS diagnosed during all of their placebo‐controlled statin trials that were at least 6 months in duration.ResultsThere were 91 US and foreign reports of ALS with statins in AERS. The data mining signal scores for ALS and statins ranged from 8.5 to 1.6. Data were obtained from 41 statin clinical trials ranging in duration from 6 months to 5 years and representing approximately 200 000 patient–years of exposure to statin and approximately 200 000 patient–years of exposure to placebo. Nine cases of ALS were reported in statin‐treated patients and 10 cases in placebo‐treated patients.ConclusionsAlthough we observed a data mining signal for ALS with statins in FDA's AERS, retrospective analyses of 41 statin clinical trials did not reveal an increased incidence of ALS in subjects treated with a statin compared with placebo. Copyright © 2008 John Wiley & Sons, Ltd.
Antistatic performance and morphological observation of ternary blends of poly(ethylene terephthalate), poly(ether esteramide), and ionomers
Authors: Kobayashi Toshikazu , Wood Barbara A. , Takemura Akio , Ono Hirokuni 
Published: September 2008

AbstractBlends of poly(ethylene terephthalate) (PET) and poly (ether esteramide) (PEEA), which is known as an ion conductive polymer, were prepared by melt mixing using a twin screw extruder. Antistatic performance of the molded plaques and the effects of adding ionomers such as lithium neutralized poly(ethylene‐co‐methacrylic acid) copolymer(E/MAA‐Li), magnesium neutralized poly(ethylene‐co‐methacrylic acid) copolymer(E/MAA‐Mg), and zinc neutralized poly(ethylene‐co‐methacrylic acid) copolymer (E/MAA‐Zn) were investigated. Antistatic effect of adding poly(ethylene‐co‐methacrylic acid) copolymer(E/MAA) and polystyrene, and poly(ethylene naphthalate) (PEN) into PET/PEEA blends were also investigated. Here we confirmed that lithium ionomer worked the most effectively in those blend systems. We also confirmed that E/MAA worked to enhance the antistatic performance of PET/PEEA blends. Morphological study of these ternary blends system was conducted by TEM. Specific interaction between PEEA and E/MAA‐Li, and E/MAA were observed. Those ionomers and copolymer domains were encapsulated by PEEA, which could increase the surface area of PEEA in PET matrix. This encapsulation effect explains the unexpected synergy for the static dissipation performance on addition of ionomers and E/MAA to PET/PEEA blends. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Autism Spectrum Disorders: Neurobiology and current assessment practices
Authors: Allen Ryan A. , Robins Diana L. , Decker Scott L. 
Published: September 2008

AbstractThis study reviews recent research related to the neurobiology of Autism Spectrum Disorders (ASDs) an provides an empirical analysis of current assessment practices. Data were collected through a survey of 117 school psychologists. The Childhood Autism Rating Scale (CARS), Gilliam Autism Rating Scale (GARS), and Gilliam Asperger's Disorder Scale (GADS) were the most frequently used measures. Among the less popular, but more intensive instruments, the Autism Diagnostic Observation Schedule (ADOS) appears to be gaining popularity within school‐based evaluations. Generally, respondents approached the assessment of ASDs from a traditional psychoeducational perspective and reported the use of a very narrow range of ASD‐specific instruments. Concerns are raised regarding the inconsistent inclusion of developmental questionnaires, parent/guardian interviews, and medical professionals in the ASD evaluation process. Implications for practice and the training of school psychologists are discussed. © 2008 Wiley Periodicals, Inc.
Efficacy of teacher in‐service training for attention‐deficit/hyperactivity disorder
Authors: Jones Heather A. , Chronis‐Tuscano Andrea 
Published: September 2008

AbstractChildren with attention‐deficit/hyperactivity disorder (ADHD) evidence many problems in the classroom. Teacher in‐service training is routinely used to inform school professionals about a number of special topics; however, the efficacy of such in‐service training for ADHD has not been established. The present study examined the efficacy of brief in‐service training focused on evidence‐based assessment and treatment of ADHD. Teachers from six schools (N = 142) in the Washington, DC, metropolitan area were randomly assigned at the school level to receive in‐service training immediately or to a waitlist control group that received in‐service training 1 month later. Measures of ADHD knowledge and use of behavior modification techniques were obtained at pre‐‐ and post‐‐in‐service intervention. Results indicated that the in‐service training resulted in increased ADHD knowledge. Special education teachers also reported increased use of behavior modification techniques resulting from the in‐service training. Clinical and research implications are presented. © 2008 Wiley Periodicals, Inc.
Coping strategies of high school students in an International Baccalaureate program
Authors: Suldo Shannon M. , Shaunessy Elizabeth , Michalowski Jessica , Shaffer Emily J. 
Published: September 2008

AbstractStudents who are enrolled in academically challenging curricula face a multitude of stressors related to increased academic demands in addition to the developmental and biological challenges that are normative to adolescence. This article presents results of a qualitative study conducted to uncover the coping styles of students in a rigorous curriculum and determine which strategies are associated with varying levels of psychopathology (specifically, low and above‐average anxiety). Forty‐eight students from an International Baccalaureate (IB) diploma program participated in eight focus groups, in which participants were grouped by level of anxiety. Following transcription analysis using grounded theory methodology, researchers identified coping strategies and the frequency of these approaches; active problem‐solving and avoidance of demands were reported most often among all IB students in this investigation. Students with above‐average levels of anxiety discussed seeking social support more often, whereas students with low anxiety more frequently discussed avoiding demands, reducing one's workload, and seeking positive emotions. © 2008 Wiley Periodicals, Inc.
Management of bipolar affective disorder during pregnancy
Authors: Meiser‐Stedman Caroline , Curtis Vivienne 
Published: September 2008

AbstractIn Pregnancy is a series of reviews focusing on the management of women with psychiatric and neurological conditions during pregnancy. In this article, Dr Meiser‐Stedman and Dr Curtis discuss the risks associated with pregnancy in women with bipolar affective disorder (BPAD) and the issues that need to be considered regarding the management of BPAD before and during pregnancy as well as immediately after the birth. Copyright © 2008 Wiley Interface Ltd
Analysis of the electrochemistry of hemes with Ems spanning 800 mV
Authors: Zheng Zhong , Gunner M. R. 
Published: September 2008

AbstractThe free energy of heme reduction in different proteins is found to vary over more than 18 kcal/mol. It is a challenge to determine how proteins manage to achieve this enormous range of Ems with a single type of redox cofactor. Proteins containing 141 unique hemes of a‐, b‐, and c‐type, with bis‐His, His‐Met, and aquo‐His ligation were calculated using Multi‐Conformation Continuum Electrostatics (MCCE). The experimental Ems range over 800 mV from −350 mV in cytochrome c3 to 450 mV in cytochrome c peroxidase (vs. SHE). The quantitative analysis of the factors that modulate heme electrochemistry includes the interactions of the heme with its ligands, the solvent, the protein backbone, and sidechains. MCCE calculated Ems are in good agreement with measured values. Using no free parameters the slope of the line comparing calculated and experimental Ems is 0.73 (R2 = 0.90), showing the method accounts for 73% of the observed Em range. Adding a +160 mV correction to the His‐Met c‐type hemes yields a slope of 0.97 (R2 = 0.93). With the correction 65% of the hemes have an absolute error smaller than 60 mV and 92% are within 120 mV. The overview of heme proteins with known structures and Ems shows both the lowest and highest potential hemes are c‐type, whereas the b‐type hemes are found in the middle Em range. In solution, bis‐His ligation lowers the Em by ≈205 mV relative to hemes with His‐Met ligands. The bis‐His, aquo‐His, and His‐Met ligated b‐type hemes all cluster about Ems which are ≈200 mV more positive in protein than in water. In contrast, the low potential bis‐His c‐type hemes are shifted little from in solution, whereas the high potential His‐Met c‐type hemes are raised by ≈300 mV from solution. The analysis shows that no single type of interaction can be identified as the most important in setting heme electrochemistry in proteins. For example, the loss of solvation (reaction field) energy, which raises the Em, has been suggested to be a major factor in tuning in situ Ems. However, the calculated solvation energy vs. experimental Em shows a slope of 0.2 and R2 of 0.5 thus correlates weakly with Ems. All other individual interactions show even less correlation with Em. However the sum of these terms does reproduce the range of observed Ems. Therefore, different proteins use different aspects of their structures to modulate the in situ heme electrochemistry. This study also shows that the calculated Ems are relatively insensitive to different heme partial charges and to the protein dielectric constant used in the simulation. Proteins 2009. © 2008 Wiley‐Liss, Inc.
Structural characterization of the tunnels of Mycobacterium tuberculosis truncated hemoglobin N from molecular dynamics simulations
Authors: Daigle Richard , Guertin Michel , Lagüe Patrick 
Published: September 2008

AbstractThe structure of oxygenated trHbN from Mycobacterium tuberculosis shows an extended heme distal hydrogen‐bond network that includes Tyr33(B10), Gln58(E11), and the bound O2. In addition, trHbN structure shows a network of hydrophobic cavities organized in two orthogonal branches. In the present work, the structure and the dynamics of oxygenated and deoxygenated trHbN in explicit water was investigated from 100 ns molecular dynamics (MD) simulations. Results show that, depending on the presence or the absence of a coordinated O2, the Tyr33(B10) and Gln58(E11) side chains adopt two different configurations in concert with hydrogen bond network rearrangement. In addition, our data indicate that Tyr33(B10) and Gln58(E11) control the dynamics of Phe62(E15). In deoxy‐trHbN, Phe62(E15) is restricted to one conformation. Upon O2 binding, the conformation of Gln58(E11) changes and residue Phe62(E15) fluctuates between two conformations. We also conducted a systematic study of trHbN tunnels by analyzing thousands of MD snapshots with CAVER. The results show that tunnel formation is the result of the dynamic reshaping of short‐lived hydrophobic cavities. The analyses indicate that the presence of these cavities is likely linked to the rigid structure of trHbN and also reveal two tunnels, EH and BE, that link the protein surface to the buried distal heme pocket and not present in the crystallographic structure. The cavities are sufficiently large to accomodate and store ligands. Tunnel dynamics in trHbN was found to be controlled by the side‐chain conformation of the Tyr33(B10), Gln58(E11), and Phe62(E15) residues. Importantly, in contrast to recently published works, our extensive systematic studies show that the presence or absence of a coordinated dioxygen does not control the opening of the long tunnel but rather the opening of the EH tunnel. In addition, the data lead to new and distinctly different conclusion on the impact of the Phe62(E15) residue on trHbN tunnels. We propose that the EH and the long tunnels are used for apolar ligands storage. The trajectories bring important new structural insights related to trHbN function and to ligand diffusion in proteins. Proteins 2009. © 2008 Wiley‐Liss, Inc.
Insecticide resistance management strategies against the western flower thrips, Frankliniella occidentalis
Authors: Bielza Pablo 
Published: September 2008

AbstractWestern flower thrips (WFT), Frankliniella occidentalis (Pergande), is an economically important pest of a wide range of crops grown throughout the world. Insecticide resistance has been documented in many populations of WFT. Biological and behavioural characteristics and pest management practices that promote insecticide resistance are discussed. In addition, an overview is provided of the development of insecticide resistance in F. occidentalis populations and the resistance mechanisms involved. Owing to widespread resistance to most conventional insecticides, a new approach to insecticide resistance management (IRM) of F. occidentalis is needed. The IRM strategy proposed consists of two parts. Firstly, a general strategy to minimise the use of insecticides in order to reduce selection pressure. Secondly, a strategy designed to avoid selection of resistance mechanisms, considering cross‐resistance patterns and resistance mechanisms. Copyright © 2008 Society of Chemical Industry
A luminescent solar concentrator with 7.1% power conversion efficiency
Authors: Slooff L. H. , Bende E. E. , Burgers A. R. , Budel T. , Pravettoni M. , Kenny R. P. , Dunlop E. D. , Büchtemann A. 
Published: September 2008

AbstractThe Luminescent Solar Concentrator (LSC) consists of a transparent polymer plate, containing luminescent particles. Solar cells are connected to one or more edges of the polymer plate. Incident light is absorbed by the luminescent particles and re‐emitted. Part of the light emitted by the luminescent particles is guided towards the solar cells by total internal reflection. Since the edge area is smaller than the receiving one, this allows for concentration of sunlight without the need for solar tracking. External Quantum Efficiency (EQE) and current–voltage (I –V) measurements were performed on LSC devices with multicrystalline silicon (mc‐Si) or GaAs cells attached to the sides. The best result was obtained for an LSC with four GaAs cells. The power conversion efficiency of this device, as measured at European Solar Test Installation laboratories, was 7.1% (geometrical concentration of a factor 2.5). With one GaAs cell attached to one edge only, the power efficiency was still as high as 4.6% (geometrical concentration of a factor 10). To our knowledge these efficiencies are among the highest reported for the LSC. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
SEAR: a secure efficientad hocon demand routing protocol for wireless networks
Authors: Li Qing , Zhao Meiyuan , Walker Jesse , Hu Yih‐Chun , Perrig Adrian , Trappe Wade 
Published: September 2008

AbstractMulti‐hop routing is essential to the operation of wirelessad hocnetworks. Unfortunately, it is very easy for an adversary to forge or modify routing messages to inflict severe damage on the underlying routing protocol. In this paper, we present SEAR, a secure efficientad hocrouting (SEAR) protocol forad hocnetworks that is mainly based on efficient symmetric cryptography, with asymmetric cryptography used only for the distribution of initial key commitments. SEAR uses one‐way hash functions to protect the propagation of the routing messages. Intermediate nodes verify the routing messages by applying one‐way functions, while malicious nodes cannot construct beneficial false routing messages when forwarding them. Route error (RERR) messages are protected through a variation of the TESLA broadcast authentication scheme. The SEAR protocol does not require any additional routing packet formats, and thus follows the same basic design asad hocon‐demand distance vector (AODV). We show, through both theoretical examination and simulations, that SEAR provides better security with significantly less overhead than other existing secure AODV (SAODV) protocols. Copyright © 2008 John Wiley & Sons, Ltd.
Biomarker discovery using targeted maximum‐likelihood estimation: Application to the treatment of antiretroviral‐resistant HIV infection
Authors: Bembom Oliver , Petersen Maya L. , Rhee Soo‐Yon , Fessel W. Jeffrey , Sinisi Sandra E. , Shafer Robert W. , van der Laan Mark J. 
Published: September 2008

AbstractResearchers in clinical science and bioinformatics frequently aim to learn which of a set of candidate biomarkers is important in determining a given outcome, and to rank the contributions of the candidates accordingly. This article introduces a new approach to research questions of this type, based on targeted maximum‐likelihood estimation of variable importance measures.The methodology is illustrated using an example drawn from the treatment of HIV infection. Specifically, given a list of candidate mutations in the protease enzyme of HIV, we aim to discover mutations that reduce clinical virologic response to antiretroviral regimens containing the protease inhibitor lopinavir. In the context of this data example, the article reviews the motivation for covariate adjustment in the biomarker discovery process. A standard maximum‐likelihood approach to this adjustment is compared with the targeted approach introduced here. Implementation of targeted maximum‐likelihood estimation in the context of biomarker discovery is discussed, and the advantages of this approach are highlighted. Results of applying targeted maximum‐likelihood estimation to identify lopinavir resistance mutations are presented and compared with results based on unadjusted mutation–outcome associations as well as results of a standard maximum‐likelihood approach to adjustment.The subset of mutations identified by targeted maximum likelihood as significant contributors to lopinavir resistance is found to be in better agreement with the current understanding of HIV antiretroviral resistance than the corresponding subsets identified by the other two approaches. This finding suggests that targeted estimation of variable importance represents a promising approach to biomarker discovery. Copyright © 2008 John Wiley & Sons, Ltd.
Modeling the association of bivariate interval‐censored data using the copula approach
Authors: Bogaerts Kris , Lesaffre Emmanuel 
Published: September 2008

AbstractIn a survival study, it may not be possible to record the exact event time but only that the event has occurred between two time points or still has to occur, leading to interval‐censored survival times.Recently, Sunet al.(Scand. J. Stat.2006;33(4):637–649) suggested to fit a Clayton copula with nonparametric marginal distributions to estimate the association for bivariate interval‐censored failure data. We propose here to model the marginal distributions with an accelerated failure time model with a flexible error term as suggested by Komáreket al.(J. Comput. Graph. Stat.2005;14(3):726–745) in combination with a one parameter copula. In addition, we allow the association parameter of the copula to depend on covariates.The performance of our method is illustrated by an extensive simulation study and is applied to tooth emergence data of permanent teeth measured on 4468 children from a longitudinal dental study. Copyright © 2008 John Wiley & Sons, Ltd.