bluuebunny/crossref_metadata_2025_split huggingface dataset:
Centring ability and apical transportation after overinstrumentation with ProTaper Universal and ProFile Vortex instruments
Authors: González Sánchez J. A. , Duran‐Sindreu F. , de Noé S. , Mercadé M. , Roig M. 
Published: January 2012

González Sánchez JA, Duran‐Sindreu F, de Noé S, Mercadé M, Roig M. Centring ability and apical transportation after overinstrumentation with ProTaper Universal and ProFile Vortex instruments. International Endodontic Journal, 45, 542–551, 2012.AbstractAim  To evaluate morphological changes to the major foramen after overinstrumentation with ProTaper Universal and ProFile Vortex Ni–Ti rotary instruments.Methodology  Twenty‐eight mesiobuccal canals of maxillary and mandibular first molars were divided into two groups of 14 canals each. The root canals were prepared with ProTaper Universal or ProFile Vortex instruments. ProTaper and Vortex instruments were used until the file tip protruded 1 mm beyond the working length (0.5 mm beyond the major foramen). The major foramen was photographed before and after overinstrumentation with each file of the two systems used. The images were superimposed and evaluated using Adobe Photoshop. The parameters evaluated were canal transportation, centring ability and shape of the major foramen. Transportation and centring ability were calculated in two directions: the direction of maximum curvature (MC) and a direction vertical to the maximum curvature (VC). Measurements of canal transportation and centring ability were analysed by anova followed by post hoc least significance difference (LSD) multiple comparisons.Results  No significant differences were observed amongst the different instruments with respect to centring ability in either direction (P > 0.05). The F3 ProTaper Universal instrument was associated with a higher mean values for transportation in the direction of MC (P < 0.05) than the S1, S2 and F1 ProTaper Universal instruments and the size 15, 0.06 taper, size 20, 0.06 taper, and size 25, 0.06 taper ProFile Vortex instruments. The size 30, 0.06 taper ProFile Vortex instrument had a larger mean value for transportation in the direction of MC (P < 0.05) than the S1 ProTaper Universal and size 15, 0.06 taper ProFile Vortex instruments. The S1, S2, F1, F2 and F3 ProTaper Universal files and the size 15, 0.06 taper, size 20, 0.06 taper, size 25, 0.06 taper, and size 30, 0.06 taper ProFile Vortex files produced an oval foramen in 71%, 71%, 85%, 85%, 71%, 71%, 85%, 85% and 89% of the cases, respectively.Conclusions  In most samples, the ProTaper Universal and ProFile Vortex files produced transportation of the major foramen and created an oval‐shaped major foramen after overinstrumentation.
Forest elephant mitochondrial genomes reveal that elephantid diversification in Africa tracked climate transitions
Authors: BRANDT ADAM L. , ISHIDA YASUKO , GEORGIADIS NICHOLAS J. , ROCA ALFRED L. 
Published: January 2012

AbstractAmong elephants, the phylogeographic patterns of mitochondrial (mt) and nuclear markers are often incongruent. One hypothesis attributes this to sex differences in dispersal and in the variance of reproductive success. We tested this hypothesis by examining the coalescent dates of genetic markers within elephantid lineages, predicting that lower dispersal and lower variance in reproductive success among females would have increased mtDNA relative to nuclear coalescent dates. We sequenced the mitochondrial genomes of two forest elephants, aligning them to mitogenomes of African savanna and Asian elephants, and of woolly mammoths, including the most divergent mitogenomes within each lineage. Using fossil calibrations, the divergence between African elephant F and S clade mitochondrial genomes (originating in forest and savanna elephant lineages, respectively) was estimated as 5.5 Ma. We estimated that the (African) ancestor of the mammoth and Asian elephant lineages diverged 6.0 Ma, indicating that four elephantid lineages had differentiated in Africa by the Miocene–Pliocene transition, concurrent with drier climates. The coalescent date for forest elephant mtDNAs wasc. 2.4 Ma, suggesting that the decrease in tropical forest cover during the Pleistocene isolated distinct African forest elephant lineages. For all elephantid lineages, the ratio of mtDNA to nuclear coalescent dates was much greater than 0.25. This is consistent with the expectation that sex differences in dispersal and in variance of reproductive success would have increased the effective population size of mtDNA relative to nuclear markers in elephantids, contributing to the persistence of incongruent mtDNA phylogeographic patterns.
Potato CONSTANS is involved in photoperiodic tuberization in a graft‐transmissible manner
Authors: González‐Schain Nahuel D. , Díaz‐Mendoza Mercedes , Żurczak Marek , Suárez‐López Paula 
Published: January 2012

SummaryCONSTANS (CO) is involved in the photoperiodic control of plant developmental processes, including flowering in several species and seasonal growth cessation and bud set in trees. It has been proposed that CO could also affect the day‐length regulation of tuber induction in Solanum tuberosum (potato), a plant of great agricultural relevance. To address this question, we examined the role of CO in potato. A potato CO‐like gene, StCO, was identified and found to be highly similar to a previously reported potato gene of unknown function. Potato plants overexpressing StCO tuberized later than wild‐type plants under a weakly inductive photoperiod. StCO silencing promoted tuberization under both repressive and weakly inductive photoperiods, but did not have any effect under strongly inductive short days, demonstrating that StCO represses tuberization in a photoperiod‐dependent manner. The effect of StCO on tuber induction was transmitted through grafts. In addition, StCO affected the mRNA levels of StBEL5 – a tuberization promoter, the mRNA of which moves long distances in potato plants – and StFT/StSP6A, a protein highly similar to FLOWERING LOCUS T (FT), which is a key component of systemic flowering signals in other species. We also found that StFT/StSP6A transcript levels correlate with the induction of tuber formation in wild‐type plants. These results show that StCO plays an important role in photoperiodic tuberization and, together with the recent demonstration that StFT/StSP6A promotes tuberization, indicate that the CO/FT module participates in controlling this process. Moreover, they support the notion that StCO is involved in the expression of long‐distance regulatory signals in potato, as CO does in other species.
Diagnostic yield of the cytomegalovirus (CMV) antigenemia assay and clinical features in solid organ transplant recipients and hematopoietic stem cell transplant recipients with CMV pneumonia
Authors: Moon S.M. , Sung H. , Kim M.‐N. , Lee S.‐O. , Choi S.‐H. , Kim Y.S. , Woo J.H. , Kim S.‐H. 
Published: January 2012

Abstract:Data are limited on the value of non‐invasive diagnostic methods, such as the cytomegalovirus (CMV) antigenemia assay, and the clinical features of CMV pneumonia in patients who have undergone solid organ transplant (SOT) compared with those who have had hematopoietic stem cell transplant (HSCT). All adult patients with suspected CMV pneumonia, who had received SOT or HSCT in a tertiary hospital during a 5‐year period, were retrospectively enrolled. CMV pneumonia was defined as clinical and radiographic evidence of pneumonia in association with the isolation of CMV in viral cultures of bronchoalveolar lavage or lung tissue specimens, or with the identification of CMV in lung tissue. In total, 36 patients with CMV pneumonia were identified. Of these, 29 (80%) had received SOT and 7 (20%) had received HSCT. The incidence of CMV pneumonia in the patients with SOT (3.0 per 1000 person‐years [95% confidence interval {CI} 0.6–8.7]) was lower than in those with HSCT (17.0 per 1000 person‐years [95% CI 9.9–27.2], P = 0.003) and CMV‐related mortality showed a tendency to have lower mortality in patients with SOT (10% [3/29]) than with HSCT (43% [3/7], P = 0.07). The overall sensitivity of the CMV assay (≥ 1/200,000 leukocytes) in patients with CMV pneumonia was 69% (95% CI 52–84%). The CMV antigenemia test is of limited value in diagnosing CMV pneumonia, given the high cost of false‐negative diagnoses of CMV pneumonia.
Multiparous cows categorized by milk protein concentration and energy‐corrected milk yield during early lactation – metabolism, productivity and effect of a short‐term feed restriction
Authors: Sigl T. , Gellrich K. , Meyer H. H. D. , Kaske M. , Wiedemann S. 
Published: January 2012

SummaryThe objective of this experiment was to study milk productivity, metabolic adaptation and effect of a short‐term feed restriction (FR) on key performance indicators during early lactation in cows classified according to energy‐corrected milk (ECM) yield and milk protein concentration. Twenty‐three multiparous Holstein–Friesian cows were categorized in four groups according to respective averaged values on Days 23–25 postpartum: high ECM yield and high protein concentration; low ECM yield and low protein concentration; high ECM yield and low protein concentration and low ECM yield and high protein concentration.Dry matter intake was reduced to 68.3% for three subsequent days. Our results showed that short‐time FR in early lactation succeeded in enhancing energy deficit of cows in all groups. Milk fat, milk protein and lactose concentrations as well as milk fat yield were not influenced by FR. Several hepatic genes encoding for enzymes involved in catabolism of amino acids, β‐oxidation, gluconeogenesis and ketogenesis as well as mRNA encoding for insulin receptor showed increased transcript abundances after FR, primarily in cows with high milk yield and low milk protein concentration.
Modular acute system for general surgery: hand over the operation, not the patient
Authors: Poole Garth H. , Glyn Tamara , Srinivasa Sanket , Hill Andrew G. 
Published: January 2012

AbstractIntroduction:  Various models have been proposed to effectively provide acute surgical care in Australasia. Recently, General Surgeons Australia (GSA) has published a 12‐point plan with guiding principles on this matter. This study describes a model of providing acute general surgical care in a high‐volume institution, evaluates clinical outcomes and critically appraises the system against the GSA 12‐point plan.Methods:  The acute care system is qualitatively described with quantitative measures of workload. The outcomes of acute laparoscopic cholecystectomy were used as a proxy of system performance. The system was critically appraised against the GSA 12‐point plan.Results:  Teams are on call once per week with each surgeon on call once per fortnight. The three key elements of acute management – collecting patients, post‐acute ward round and operating – are treated as modules. The patient remains under the care of the admitting consultant but is often operated on by another team. From June 2009 to 2010, there were 7429 acute general surgical admissions (mean: 20.4 patients per day) with 2999 acute operations (mean: 8.4 operations per day). The other activities of the department were not compromised. In that time, 388 acute laparoscopic cholecystectomies were performed with a conversion rate of 1.3% and no major bile duct injury. The system is compatible with the GSA 12‐point plan.Conclusion:  This study describes an efficient and safe system for providing acute general surgical care in a high‐volume setting with satisfactory clinical outcomes. It is compatible with the GSA 12‐point plan.
Common bacterial responses in six ecosystems exposed to 10 years of elevated atmospheric carbon dioxide
Authors: Dunbar John , Eichorst Stephanie A. , Gallegos‐Graves La Verne , Silva Shannon , Xie Gary , Hengartner N. W. , Evans R. David , Hungate Bruce A. , Jackson Robert B. , Megonigal J. Patrick , Schadt Christopher W. , Vilgalys Rytas , Zak Donald R. , Kuske Cheryl R. 
Published: January 2012

SummarySix terrestrial ecosystems in the USA were exposed to elevated atmospheric CO2 in single or multifactorial experiments for more than a decade to assess potential impacts. We retrospectively assessed soil bacterial community responses in all six‐field experiments and found ecosystem‐specific and common patterns of soil bacterial community response to elevated CO2. Soil bacterial composition differed greatly across the six ecosystems. No common effect of elevated atmospheric CO2 on bacterial biomass, richness and community composition across all of the ecosystems was identified, although significant responses were detected in individual ecosystems. The most striking common trend across the sites was a decrease of up to 3.5‐fold in the relative abundance of Acidobacteria Group 1 bacteria in soils exposed to elevated CO2 or other climate factors. The Acidobacteria Group 1 response observed in exploratory 16S rRNA gene clone library surveys was validated in one ecosystem by 100‐fold deeper sequencing and semi‐quantitative PCR assays. Collectively, the 16S rRNA gene sequencing approach revealed influences of elevated CO2 on multiple ecosystems. Although few common trends across the ecosystems were detected in the small surveys, the trends may be harbingers of more substantive changes in less abundant, more sensitive taxa that can only be detected by deeper surveys.
Well‐being among employed and non‐employed caregiving women in Taiwan
Authors: Chou Yueh‐Ching , Kröger Teppo , Chiao Chi , Pu Cheng‐yun 
Published: January 2012

Chou Y‐C, Kröger T, Chiao C, Pu C‐Y. Well‐being among employed and non‐employed caregiving women in TaiwanThis study addressed various groups of non‐employed/employed and non‐caring/caring women in Taiwan. Data from the 2006 National Taiwanese Women Survey (at age 16–64, n= 6,017) were analysed to determine whether there are differences in terms of well‐being, as measured by self‐rated health and family life satisfaction, between women who work and/or care and between different carer groups. Other factors associated with well‐being of carers of young children (n= 1,697) were also analysed. The results showed that non‐employed carers of disabled adults stood out as the most disadvantaged group. However, the importance of work has been replaced by support among carers of young children. This study suggests that unpaid carers, particularly carers of disabled adults who are non‐employed, ought to be supported by policies. To improve carers' well‐being, care–work reconciliation among working‐age women needs to be included in the future care scheme in Taiwan.
The local geographies of welfare in Tunisia: Does neighbourhood matter?*
Authors: Amara Mohamed , Ayadi Mohamed 
Published: January 2012

Amara M, Ayadi M. The local geographies of welfare in Tunisia: Does neighbourhood matter?The aim of this article is to show that spatial analysis techniques outperform non‐spatial statistical counterparts for understanding the geographic determinants of welfare and poverty in Tunisia. First, an Exploratory Spatial Data Analysis, based on a Geographical Information System, was conducted to visualise the local spatial structure of welfare. Second, a spatial autoregressive (SAR) model and a geographically weighted regression (GWR) model, respectively, were used to deal with both spatial autocorrelations and unobserved spatial heterogeneity of households' behaviours. Spatial and non‐spatial models were compared according to their predictive performances. Results of this case study confirm that SAR and GWR spatial models are preferable to the traditional non‐spatial regression model and that they give a better approximation of the Tunisian poverty map.
Glucose challenge test for detecting gestational diabetes mellitus: a systematic review
Authors: van Leeuwen M , Louwerse MD , Opmeer BC , Limpens J , Serlie MJ , Reitsma JB , Mol BWJ 
Published: January 2012

Please cite this paper as: van Leeuwen M, Louwerse M, Opmeer B, Limpens J, Serlie M, Reitsma J, Mol B. Glucose challenge test for detecting gestational diabetes mellitus: a systematic review. BJOG 2012;119:393–401.Background  The best strategy to identify women with gestational diabetes mellitus (GDM) is unclear.Objectives  To perform a systematic review to calculate summary estimates of the sensitivity and specificity of the 50‐g glucose challenge test for GDM.Search strategy  Systematic search of MEDLINE, EMBASE and Web of Science.Selection criteria  Articles that compared the 50‐g glucose challenge test with the oral glucose tolerance test (OGTT, with a 75‐ or 100‐g reference standard) before 32 weeks of gestation.Data collection and analysis  Summary estimates of sensitivity and specificity, with 95% confidence intervals and summary receiver operating characteristic curves, were calculated using bivariate random‐effects models. Two reviewers independently selected articles that compared the 50 g glucose challenge test to the oral glucose tolerance test (OGTT, 75 or 100 gram, reference standard) before 32 weeks of gestation.Main results  Twenty‐six studies were included (13 564 women). Studies that included women with risk factors showed a pooled sensitivity of the 50‐g glucose challenge test of 0.74 (95% CI 0.62–0.87), a pooled specificity of 0.77 (95% CI 0.66–0.89) (threshold value of 7.8 mmol/l), a derived positive likelihood ratio (LR) of 3.2 (95% CI 2.0–5.2) and a negative LR of 0.34 (95% CI 0.22–0.53). In studies with consecutive recruitment, the pooled sensitivity was 0.74 (95% CI 0.62–0.87) for a specificity of 0.85 (95% CI 0.80–0.91), with a derived positive LR of 4.9 (95% CI 3.5–7.0) and negative LR of 0.31 (95% CI 0.20–0.47). Increasing the threshold for disease (OGTT result) increased the sensitivity of the challenge test, and decreased the specificity.Author’s conclusions  The 50‐g glucose challenge test is acceptable to screen for GDM, but cannot replace the OGTT. Further possibilities of combining the 50‐g glucose challenge test with other screening strategies should be explored.
Factors influencing uptake and timing of risk reducing salpingo‐oophorectomy in women at risk of familial ovarian cancer: a competing risk time to event analysis
Authors: Manchanda R , Burnell M , Abdelraheim A , Johnson M , Sharma A , Benjamin E , Brunell C , Saridogan E , Gessler S , Oram D , Side L , Rosenthal AN , Jacobs I , Menon U 
Published: January 2012

Please cite this paper as:Manchanda R, Burnell M, Abdelraheim A, Johnson M, Sharma A, Benjamin E, Brunell C, Saridogan E, Gessler S, Oram D, Side L, Rosenthal A, Jacobs I, Menon U. Factors influencing uptake and timing of risk reducing salpingo‐oophorectomy in women at risk of familial ovarian cancer: a competing risk time to event analysis. BJOG 2012;119:527–536.Objective To evaluate factors affecting uptake of risk‐reducing salpingo‐oophorectomy (RRSO) over time in women at high‐risk of familial ovarian cancer.Design Prospective observational cohort.Setting Tertiary high‐risk familial gynaecological cancer clinic.Population/sample New clinic attendees between March 2004 and November 2009, fulfilling the high‐risk criteria for the UK Familial Ovarian Cancer Screening Study.Methods Risk management options discussed included RRSO and ovarian surveillance. Outcome data were analysed from a bespoke database. The competing risk method was used to model the cumulative incidence function (CIF) of RRSO over time, and the sub‐hazard ratio (SHR) was used to assess the strength of the association of variables of interest with RRSO. Gray’s test was used to evaluate the difference in CIF between two groups and multivariable competing risk regression analysis was used to model the cumulative probabilities of covariates on the CIF.Results Of 1133 eligible women, 265 (21.4%) opted for RRSO and 868 (69.9%) chose screening. Women undergoing RRSO were older (49 years, interquartile range 12.2 years) than those preferring screening (43.4 years, interquartile range 11.9 years) (P < 0.0005). The CIF for RRSO at 5 years was 0.55 (95% CI 0.45–0.64) forBRCA1/2carriers and 0.22 (95% CI 0.19–0.26) for women of unknown mutation status (P < 0.0001); 0.42 (95% CI 0.36–0.47) for postmenopausal women (P < 0.0001); 0.29 (95% CI 0.25–0.33) for parity ≥1 (P = 0.009) and 0.47 (95% CI 0.39–0.55) for a personal history of breast cancer (P < 0.0001). Variables of significance from the regression analysis were: aBRCA1/2mutation (SHR 2.31, 95% CI 1.7–3.14), postmenopausal status (SHR 2.16, 95% CI 1.62–2.87)) and a personal history of breast cancer (SHR 1.5, 95% CI 1.09–2.06).Conclusions Decision‐making is a complex process and women opt for surgery many years after initial risk assessment.BRCAcarriers, postmenopausal women and women who had breast cancer are significantly more likely to opt for preventative surgery.
Ammonia increases paracellular permeability of rat brain endothelial cells by a mechanism encompassing oxidative/nitrosative stress and activation of matrix metalloproteinases
Authors: Skowrońska Marta , Zielińska Magdalena , Wójcik‐Stanaszek Luiza , Ruszkiewicz Joanna , Milatovic Dejan , Aschner Michael , Albrecht Jan 
Published: January 2012

J. Neurochem. (2012) 121, 125–134.AbstractAmmonia is responsible for cerebral edema associated with acute liver failure, but the role of the vasogenic mechanism has been a matter of dispute. Here, we tested the hypothesis that ammonia induces changes in blood–brain barrier (BBB) permeability by a mechanism coupled to oxidative/nitrosative stress (ONS) evoked in the BBB‐forming cerebral capillary endothelial cells. Treatment of a rat brain endothelial cell line with ammonia (5 mmol/L, 24 h) caused accumulation of ONS markers: reactive oxygen species, nitric oxide and peroxidation products of phospholipid‐bound arachidonic acid, F2‐isoprostanes. Concurrently, ammonia increased the activity of extracellular matrix metalloproteinases (MMP‐2/MMP‐9), increased cell permeability to fluorescein isothiocyanate‐dextran (40 kDa), and increased the expression of y+LAT2, a transporter that mediates the uptake to the cells of the nitric oxide precursor, arginine. The increase of cell permeability was ameliorated upon co‐treatment with a MMP inhibitor, SB‐3CT and with an antioxidant, glutathione diethyl ester, which also reduced F2‐isoprostanes. Ammonia‐induced ONS was attenuated by cytoprotective agents l‐ornithine, phenylbutyrate, and their conjugate l‐ornithine phenylbutyrate, an ammonia‐trapping drug used to treat hyperammonemia. The results support the concept that ONS and ONS‐related activation of MMPs in cerebral capillary endothelial cells contribute to the alterations in BBB permeability and to the vasogenic component of cerebral edema associated with acute liver failure.
Equity Risk Incentives and Corporate Tax Aggressiveness
Authors: REGO SONJA OLHOFT , WILSON RYAN 
Published: January 2012

ABSTRACT This study examines equity risk incentives as one determinant of corporate tax aggressiveness. Prior research finds that equity risk incentives motivate managers to make risky investment and financing decisions, since risky activities increase stock return volatility and the value of stock option portfolios. Aggressive tax strategies involve significant uncertainty and can impose costs on both firms and managers. As a result, managers must be incentivized to engage in risky tax avoidance that is expected to generate net benefits for the firm and its shareholders. We predict that equity risk incentives motivate managers to undertake risky tax strategies. Consistent with this prediction, we find that larger equity risk incentives are associated with greater tax risk and the magnitude of this effect is economically significant. Our results are robust across four measures of tax risk, but do not vary across several proxies for strength of corporate governance. We conclude that equity risk incentives are a significant determinant of corporate tax aggressiveness.