bluuebunny/crossref_metadata_2025_split huggingface dataset:
Joint modeling of longitudinal and survival data with missing and left‐censored time‐varying covariates
Authors: Chen Qingxia , May Ryan C. , Ibrahim Joseph G. , Chu Haitao , Cole Stephen R. 
Published: June 2014

AbstractWe propose a joint model for longitudinal and survival data with time‐varying covariates subject to detection limits and intermittent missingness at random. The model is motivated by data from the Multicenter AIDS Cohort Study (MACS), in which HIV+ subjects have viral load and CD4 cell count measured at repeated visits along with survival data. We model the longitudinal component using a normal linear mixed model, modeling the trajectory of CD4 cell count by regressing on viral load, and other covariates. The viral load data are subject to both left censoring because of detection limits (17%) and intermittent missingness (27%). The survival component of the joint model is a Cox model with time‐dependent covariates for death because of AIDS. The longitudinal and survival models are linked using the trajectory function of the linear mixed model. A Bayesian analysis is conducted on the MACS data using the proposed joint model. The proposed method is shown to improve the precision of estimates when compared with alternative methods. Copyright © 2014 John Wiley & Sons, Ltd.
On the plastic analysis of concentrically braced frames with shear panel, obtaining predetermined collapse mechanism
Authors: Akbari Hamed Arash , Mofid Massood 
Published: June 2014

SummaryConventional design methods do not ensure that the desired collapse mechanism is developed at target displacement. In this paper, a case study is presented to analyze concentrically braced frames with steel shear panel (CBFSP). Also, extensive investigation in the failure modes are made, to have the global yielding mode at the final state. For this purpose, each of one‐story, three‐story, six‐story and nine‐story CBFSP models were decomposed into three parts where the members' closed‐form equations of internal forces were identified and superimposed. On the basis of the kinematic theorem of plastic collapse, the possible mechanisms and the related energy equations were defined to estimate the lateral load multiplier. First, the shear panels, columns, vertical and horizontal boundary elements were designed using the values of internal forces and seismic loads. Next, sections of the beams and braces were selected by constraining, where the mechanism equilibrium curve of the desired mechanism had to be placed below the others within the admissible roof displacement. Finally, for assessment of the precision of the method, results of the pushover analysis of the finite element models were compared with the theoretical ones. The findings show that, despite more effort for design, the investigated method is reliable and satisfactory. Copyright © 2014 John Wiley & Sons, Ltd.
Pd0‐Mediated Rapid Cross‐Coupling Reactions, the Rapid C‐[11C]Methylations, Revolutionarily Advancing the Syntheses of Short‐Lived PET Molecular Probes
Authors: Suzuki Masaaki , Doi Hisashi , Koyama Hiroko , Zhang Zhouen , Hosoya Takamitsu , Onoe Hirotaka , Watanabe Yasuyoshi 
Published: June 2014

AbstractPositron emission tomography is a noninvasive method for monitoring drug (or diagnostic) behavior and its localization on the target molecules in the living systems, including the human body, using a short‐lived positron‐emitting radionuclide. New methodologies for introducing representative short‐lived radionuclides, 11C and 18F, into the carbon frameworks of biologically active organic compounds have been established by developing rapid C‐[11C]methylations and C‐[18F]fluoromethylations using rapid Pd0‐mediated cross‐coupling reactions between [11C]methyl iodide (sp3‐hybridized carbon) and an excess amount of organotributylstannane or organoboronic acid ester having sp2(phenyl, heteroaromatic, or alkenyl), sp(alkynyl), or sp3(benzyl and cinnamyl)‐hybridized carbons; and [18F]fluoromethyl halide (iodide or bromide) and an organoboronic acid ester, respectively. These rapid reactions provide a firm foundation for an efficient and general synthesis of short‐lived 11C‐ or 18F‐labeled PET molecular probes to promote in vivo molecular imaging studies.
Offshore winds mapped from satellite remote sensing
Authors: Hasager Charlotte Bay 
Published: June 2014

Around 2000 wind turbines in 58 offshore wind farms produce wind energy in the Northern European seas and many new wind farms are foreseen. The wind resource assessment is costly to observe using traditional meteorological masts and therefore atmospheric modeling is state of the art. However, to reduce the uncertainty on the model results on the offshore wind resource, it is necessary to compare model results with observations. Observations from ground‐based wind lidar and satellite remote sensing are the two main technologies that can provide new types of offshore wind data at relatively low cost. The advantages of microwave satellite remote sensing are (1) horizontal spatial coverage, (2) long data archives, and (3) high spatial detail both in the coastal zone and of far‐field wind farm wake. Passive microwave ocean wind speed data are available since 1987 with up to six observations per day with near‐global coverage. The data are particularly useful for investigation of long‐term wind conditions. Scatterometer ocean surface wind vectors provide a continuous series since 1999 with twice‐daily near‐global coverage. Both types of data have grid cells around 25 km. In contrast, synthetic aperture radar (SAR) wind maps can be retrieved at 1‐km grid resolution. SAR‐based wind maps have been used for wind resource assessment far offshore and in the coastal zones with good results when compared to e.g., meteorological data and mesoscale model results. High‐resolution SAR data show very long far‐field wind farm wakes. Thus wind farm wake loss is foreseen in wind farm clusters. WIREs Energy Environ 2014, 3:594–603. doi: 10.1002/wene.123This article is categorized under:

Wind Power > Science and Materials
Occult Risk of Broken Instruments for Endoscopy‐assisted Surgery
Authors: Yasuhara Hiroshi , Fukatsu Kazuhiko , Komatsu Takami , Murakoshi Satoshi , Saito Yuhei , Uetera Yushi 
Published: June 2014

AbstractBackgroundThe influence of broken sophisticated surgical instruments on the safety of surgery has yet to be determined, in spite of an assumption that breakage of surgical instruments is not associated with critical incidents. The purpose of the present study was to delineate the risk from breakage of surgical instruments used in surgery assisted by endoscopy.MethodsA retrospective analysis was conducted to determine the frequency of breakage of instruments used in 39,817 operations from 2007 to 2011. Data of breakage were collected using incident/near‐incident reports and the request forms for repair of broken instruments.ResultsDuring the study period, 441 instruments were reported to be broken intraoperatively, and 7,541 were found to be broken on inspection. The incidence of breakage adjusted by the number of operations and the number of uses suggested that instruments for endoscopy‐assisted surgery are broken more frequently intraoperatively than are any other type of instruments (visceral surgery: 0.039 versus 0.017, P = 0.0002, RR = 2.318; obstetrics/gynecology: 0.023 versus 0.0067, P < 0.0001, RR = 3.461; thoracic surgery: 0.019 versus 0.004, P = 0.0772, RR = 5.212). Inappropriate use and wearing out were two major possible causes of breakage of instruments. The predominant adverse events were suggested to be attributable to parts falling off broken instruments because of inappropriate use.ConclusionsOur results demonstrated that surgery assisted by endoscopy has its own occult risk, which has not been previously highlighted. Minimally invasive surgery is not necessarily safe with respect to breakage of surgical instruments. Our data provide substantial evidence for higher risk of instrument breakage in endoscopy‐assisted surgery, as well as its possible detrimental effect on patient safety.
Is the Outcome of a Salvage Surgery for T4 Thoracic Esophageal Squamous Cell Carcinoma Really Poor?
Authors: Akutsu Yasunori , Kono Tsuguaki , Uesato Masaya , Hoshino Isamu , Murakami Kentaro , Aoyagi Tomoyoshi , Ota Takumi , Toyozumi Takeshi , Suito Hiroshi , Kobayashi Hiroki , Harada Rintaro , Uno Takashi , Matsubara Hisahiro 
Published: June 2014

AbstractBackgroundAmong patients with T4 thoracic esophageal squamous cell carcinoma (TESCC), it is unclear whether the outcomes of late responders who undergo high‐dose chemoradiotherapy (CRT) followed by salvage esophagectomy differs from those of early responders who undergo low‐dose CRT followed by esophagectomy.MethodsA total of 153 patients with T4 TESCC were treated with CRT. The first evaluation was performed after 40 Gy of CRT for downstaging. Of these, 28 patients could be downstaged, and underwent subsequent surgery (early responders). For the remaining patients, additional CRT was administered, and patients were re‐evaluated after treatment and underwent salvage surgery. In total, 40 patients (early + late responders) were analyzed.ResultsThe primary tumors exhibited a grade 3 response in six (21.4 %) of the early responders and two (16.7 %) of the late responders (p = 1.000). The rate of residual tumor in the primary tumor was 80 % (32/40 patients). The proportions of resected lymph nodes and positive metastatic nodes were similar between early and late responders (p = 0.406 and p = 0.859, respectively). The 5‐year overall survival rates among the early and late responders were 25.9 and 36.5 %, respectively, and the median survival times were 24.8 and 24.3 months (p = 0.925), respectively. The 5‐year cause‐specific survival rates in the early and late responder groups were 61.5 and 72.9 % (p = 0.425), respectively.ConclusionThe outcomes of both early and late responders to CRT were similar, and salvage surgery for T4 TESCC outweighs the risks in patients with T4 TESCC.
Enhanced freeze tolerance of baker’s yeast by overexpressed trehalose-6-phosphate synthase gene (TPS1) and deleted trehalase genes in frozen dough
Authors: Tan Haigang , Dong Jian , Wang Guanglu , Xu Haiyan , Zhang Cuiying , Xiao Dongguang 
Published: June 2014

Abstract
Several recombinant strains with overexpressed trehalose-6-phosphate synthase gene (TPS1) and/or deleted trehalase genes were obtained to elucidate the relationships between TPS1, trehalase genes, content of intracellular trehalose and freeze tolerance of baker’s yeast, as well as improve the fermentation properties of lean dough after freezing. In this study, strain TL301TPS1 overexpressing TPS1 showed 62.92 % higher trehalose-6-phosphate synthase (Tps1) activity and enhanced the content of intracellular trehalose than the parental strain. Deleting ATH1 exerted a significant effect on trehalase activities and the degradation amount of intracellular trehalose during the first 30 min of prefermentation. This finding indicates that acid trehalase (Ath1) plays a role in intracellular trehalose degradation. NTH2 encodes a functional neutral trehalase (Nth2) that was significantly involved in intracellular trehalose degradation in the absence of the NTH1 and/or ATH1 gene. The survival ratio, freeze-tolerance ratio and relative fermentation ability of strain TL301TPS1 were approximately twice as high as those of the parental strain (BY6-9α). The increase in freeze tolerance of strain TL301TPS1 was accompanied by relatively low trehalase activity, high Tps1 activity and high residual content of intracellular trehalose. Our results suggest that overexpressing TPS1 and deleting trehalase genes are sufficient to improve the freeze tolerance of baker’s yeast in frozen dough. The present study provides guidance for the commercial baking industry as well as the research on the intracellular trehalose mobilization and freeze tolerance of baker’s yeast.
The Effect of Different Cold Storage Conditions on the Compositions of Extra Virgin Olive Oil
Authors: Li Xueqi , Zhu Hanjiang , Shoemaker Charles F. , Wang Selina C. 
Published: June 2014

AbstractStorage conditions can affect the stability and quality of extra virgin olive oil (EVOO). While many studies have reported the influence of high temperature and light exposure during storage, little is known on the influence of the cold storage. The aim of this study was to evaluate the effect of different storage conditions (25, 4.5 and −27 °C) on the various compositions of EVOO and to determine if cold storage will prolong shelf‐life by retarding hydrolysis and oxidation. The changes of quality indices (FFA, PV, and UV) and natural antioxidants such as α‐tocopherol and phenolic compounds were evaluated periodically during storage. The characterization and quantification of phenolics were achieved by ultra‐performance liquid chromatography—diode array detector (UPLC‐DAD). In addition, 1, 2‐diacylglycerols (DAGs), pyropheophytin A (PPP) were measured to indicate thermal degradation during storage.
Levels of brain derived neurotrophic factors across gestation in women with preeclampsia
Authors: D'Souza Vandita , Patil Vidya , Pisal Hemlata , Randhir Karuna , Joshi Asmita , Mehendale Savita , Wagh Girija , Gupte Sanjay , Joshi Sadhana 
Published: June 2014

AbstractPreeclampsia (PE) is a major pregnancy complication of placental origin which leads to adverse pregnancy outcome. Brain derived neurotrophic factor (BDNF) is suggested to promote trophoblast growth and regulate placental and fetal development. This study for the first time examines the levels of maternal plasma BDNF at various time points during gestation, cord plasma and placental BDNF levels and their association with birth outcome in women with PE. Normotensive control (NC) women (n = 89) and women with PE (n = 61) were followed at three different time points [16–20 weeks (T1), 26–30 weeks (T2) and at delivery (T3)]. Maternal blood at all time points and cord blood was collected. Results indicate that maternal BDNF levels at T1 (p = 0.050) and T3 (p = 0.025) were lower in women with PE than in NC women. Cord BDNF levels at delivery in women with PE were lower (p = 0.032) than those in NC women. Placental BDNF gene expression was also lower (p = 0.0082) in women with PE than in NC women. Our data suggests that BDNF plays an important role in the development of the materno‐fetal–placental unit during pregnancy. Alteration in the levels of BDNF during pregnancy may be associated with an abnormal development of the placenta resulting in PE.
Accuracy of Initial Critical Care Triage Decisions in Blast Versus Non-Blast Trauma
Authors: Lipsky Ari M. , Klein Yoram , Givon Adi , Klein Moti , Hammond Jeffrey S. , Peleg Kobi ,   Israeli Trauma Group (ITG)
Published: June 2014

ABSTRACTObjectiveWe investigated the accuracy of initial critical care triage in blast-injured versus non-blast-injured trauma patients, focusing on those inappropriately triaged to the intensive care unit (ICU) for brief (<16 h) stays.MethodsWe conducted a retrospective review of the Israel National Trauma Registry, applying a predetermined definition of need for initial ICU admission.ResultsA total of 883 blast-injured and 112 185 non-blast-injured patients were categorized according to their need for ICU admission. Of these admissions, 5.7% in the blast setting and 8.4% in the non-blast setting were considered unnecessary. The sensitivity, specificity, and positive and negative likelihood ratios for the triage officers' decisions in assigning patients to the ICU were 95.5%, 98.8%, 77.2, and 0.05, respectively, in the blast setting, and 91.2%, 99.5%, 200.5, and 0.09, respectively, in the non-blast setting.ConclusionsTriage officers do a better job sending to the ICU only those patients who require initial intensive care in the non-blast setting, though this is obscured by a much greater overall need for ICU-level care in the blast setting. Implementing triage protocols in the blast setting may help reduce the number of patients sent initially to the ICU for brief periods, thus increasing the availability of this resource. (Disaster Med Public Health Preparedness. 2014;0:1–7)
Reconnection of skewed vortices
Authors: Kimura Y. , Moffatt H. K. 
Published: June 2014

AbstractBased on experimental evidence that vortex reconnection commences with the approach of nearly antiparallel segments of vorticity, a linearised model is developed in which two Burgers-type vortices are driven together and stretched by an ambient irrotational strain field induced by more remote vorticity. When these Burgers vortices are exactly antiparallel, they are annihilated on the strain time-scale, independent of kinematic viscosity $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}\nu $ in the limit $\nu \rightarrow 0$. When the vortices are skew to each other, they are annihilated under this action over a local extent that increases exponentially in the stretching direction, with clear evidence of reconnection on the same strain time-scale. The initial helicity associated with the skewed geometry is eliminated during the process of reconnection. The model applies equally to the reconnection of weak magnetic flux tubes under the action of a strain field, when Lorentz forces are negligible.
NITROUS OXIDE AND CARBON DIOXIDE EMISSION FROM MAIZE (Zea maysL.) UNDER FERTILISER APPLICATION AND ELEVATED CARBON DIOXIDE IN NORTHWEST INDIA
Authors: DARIPA A. , BHATIA A. , TOMER R. , SINGH S. D. , JAIN N. , PATHAK H. 
Published: June 2014

SUMMARYA field experiment was carried out at the farm of Indian Agricultural Research Institute, New Delhi to quantify the effect of elevated carbon dioxide (CO2) and different levels of N fertiliser application on nitrous oxide (N2O) and carbon dioxide (CO2) emissions from soil under maize. The experiment included five treatments: 60 kg N ha−1under ambient CO2(385 ppm) in open plots, 120 kg N ha−1under ambient CO2(385 ppm) in open plots, 160 kg N ha−1under ambient CO2(385 ppm) in open plots, 120 kg N ha−1under ambient CO2(385 ppm) in open top chambers (OTC) and 120 kg N ha−1under elevated CO2(500 ± 50 ppm) in the OTC. Peaks of N2O flux were observed after every dose of N application. Cumulative N2O emission was 13% lower under ambient CO2as compared to the elevated CO2concentrations. There was an increase in CO2emissions with application of N from 60 kg ha−1to 160 kg ha−1. Higher yield and root biomass was observed under higher N treatment (160 kg N ha−1). There was no significant increase in maize yield under elevated CO2as compared to ambient CO2. The carbon emitted was more than the carbon fixed under elevated CO2as compared to ambient CO2levels. The carbon efficiency ratio (C fixed/C emitted) was highest in ambient CO2treatment in the OTC.
Substance use disorders and co-morbidities among Asian Americans and Native Hawaiians/Pacific Islanders
Authors: Wu L.-T. , Blazer D. G. 
Published: June 2014

BackgroundAsian Americans (AAs) and Native Hawaiians/Pacific Islanders (NHs/PIs) are the fastest growing segments of the US population. However, their population sizes are small, and thus AAs and NHs/PIs are often aggregated into a single racial/ethnic group or omitted from research and health statistics. The groups' substance use disorders (SUDs) and treatment needs have been under-recognized.MethodWe examined recent epidemiological data on the extent of alcohol and drug use disorders and the use of treatment services by AAs and NHs/PIs.ResultsNHs/PIs on average were less educated and had lower levels of household income than AAs. Considered as a single group, AAs and NHs/PIs showed a low prevalence of substance use and disorders. Analyses of survey data that compared AAs and NHs/PIs revealed higher prevalences of substance use (alcohol, drugs), depression and delinquency among NHs than among AAs. Among treatment-seeking patients in mental healthcare settings, NHs/PIs had higher prevalences of DSM-IV diagnoses than AAs (alcohol/drug, mood, adjustment, childhood-onset disruptive or impulse-control disorders), although co-morbidity was common in both groups. AAs and NHs/PIs with an SUD were unlikely to use treatment, especially treatment for alcohol problems, and treatment use tended to be related to involvement with the criminal justice system.ConclusionsAlthough available data are limited by small sample sizes of AAs and NHs/PIs, they demonstrate the need to separate AAs and NHs/PIs in health statistics and increase research into substance use and treatment needs for these fast-growing but understudied population groups.
Differences in prefrontal blood oxygenation during an acute multitasking stressor in ecstasy polydrug users
Authors: Roberts C. A. , Wetherell M. A. , Fisk J. E. , Montgomery C. 
Published: June 2014

BackgroundCognitive deficits are well documented in ecstasy (3,4-methylenedioxymethamphetamine; MDMA) users, with such deficits being taken as evidence of dysregulation of the serotonin (5-hydroxytryptamine; 5-HT) system. More recently neuroimaging has been used to corroborate these deficits. The present study aimed to assess multitasking performance in ecstasy polydrug users, polydrug users and drug-naive individuals. It was predicted that ecstasy polydrug users would perform worse than non-users on the behavioural measure and this would be supported by differences in cortical blood oxygenation.MethodIn the study, 20 ecstasy-polydrug users, 17 polydrug users and 19 drug-naive individuals took part. On day 1, drug use history was taken and questionnaire measures were completed. On day 2, participants completed a 20-min multitasking stressor while brain blood oxygenation was measured using functional near infrared spectroscopy (fNIRS).ResultsThere were no significant differences between the three groups on the subscales of the multitasking stressor. In addition, there were no significant differences on self-report measures of perceived workload (NASA Task Load Index). In terms of mood, ecstasy users were significantly less calm and less relaxed compared with drug-naive controls. There were also significant differences at three voxels on the fNIRS, indicating decreased blood oxygenation in ecstasy users compared with drug-naive controls at voxel 2 (left dorsolateral prefrontal cortex), voxel 14 and voxel 16 (right dorsolateral prefrontal cortex), and compared with polydrug controls at V14.ConclusionsThe results of the present study provide support for changes in brain activation during performance of demanding tasks in ecstasy polydrug users, which could be related to cerebral vasoconstriction.
Emperors and Deities in Rural Britain: A Copper-Alloy Head of Marcus Aurelius from Steane, near Brackley (Northants.)
Authors: Walker Susan 
Published: June 2014

AbstractA half-life-sized copper-alloy head of a bearded man was published in the Portable Antiquities Scheme's report of finds from Roman Britain in 2009.1 The head was purchased by the Ashmolean Museum in 2011. In this paper evidence for the identification of the subject as a portrait of the emperor Marcus Aurelius is reviewed by comparison with metropolitan and other certainly identified heads of deities and portraits of the emperor. The technique and likely function of the head are compared with those of similarly worked Roman copper-alloy heads of emperors and deities found in South-East Britain. Finally, a brief account is given of geophysical survey and trial excavation conducted in 2012–13 in the field where the head was found. This offers a unique opportunity to explore the head's archaeological context.