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Impressed anodic current techniques are used widely to accelerate corrosion of steel embedded in concrete in the laboratory. This paper investigates the relationship between applied current density, degree of corrosion, type of corrosion and ultimate strength of corroded beams. Twenty beams were divided into four groups with a 0.5, 1, 2.5 or 5% degree of corrosion. Current densities of 0.25, 0.5, 1.0 or 2.5 mA/cm2 were applied to each group, respectively. The beams were flexurally tested and the reinforcing steel bars were retrieved, cleaned, weighed and the surface examined. The results demonstrated that higher current densities and degree of corrosion caused more localised corrosion. The applied current density has little effect on the degree of corrosion and on ultimate strength of the same degree of corroded beam. Based on this work, a current density of 1 mA/cm2 is recommended for the artificial acceleration of corrosion for steel embedded in concrete. [ABSTRACT FROM AUTHOR]

The dual function of a carbon fibre reinforced polymer (CFRP) rod working as the near-surface mounted (NSM) strengthening and impressed current cathodic protection (ICCP) anode for corroded reinforced concrete structures has been proposed and researched. In this paper, a CFRP rod was used for both flexural strengthening of pre-corroded reinforced concrete beams and in a dual functional capacity as an ICCP anode. After a period of ICCP operation at high current density, the beams were subjected to flexural testing to determine the load–deflection relationships. The potential decays of the steel met recognised ICCP standards, and the CFRP remained effective in strengthening the corroded reinforced concrete beams. The bonding at the CFRP rod anode and concrete interface was improved by using a combination of geopolymer and epoxy resin; therefore, the ultimate strength of a dual function CFRP rod with combination of bonding medium (geopolymer and epoxy) increased significantly. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology for using survey data to understand the composition of elites, through analysing the pool of potential members. An occupational-based measure of ‘potential power elite’ (PPE) is created and compared with other measures of occupational advantage. It is argued that this measure can be utilised to explore if the processes causing certain social groups to be under-represented in elite positions are around selection or the population recruited from. We provide analysis of elite positions in the UK and Sweden, demonstrating differences in terms of the potential pool of elite members and the occupational histories of people of those employed in roles associated with elite recruitment. We argue that understanding the composition of the PPE provides a more nuanced analysis of the processes of meritocracy in accessing positions of power and social influence. [ABSTRACT FROM PUBLISHER]

The article presents a descriptive review of the various patterns of association with school bullying that were revealed in a survey of over 26,000 children aged 11-16 in South Wales. The survey examined risks and protective factors for young people and included a question about being a bully and another about being bullied. Following regression analyses, significant associations were found between being a bully and various attitudinal and behavioural factors. There was a modest but ambiguous association with socio-economic status, and no independent association with minority ethnicity. There was a strong independent association between being a bully and being bullied. Some comment is made about the implications of the findings for policy, including the apparently positive effect (as revealed in the survey data) of schools being perceived by children as having clear rules on bullying. [ABSTRACT FROM AUTHOR]

The article examines the effect of the toxic baits containing sodium fluoroacetate (1080) on the fish and invertebrate communities in small streams in New Zealand. The ecological effect of 1080 leaching was assessed on three species of native fish and caddisflies in four streams using a before-after control-impact (BACI) experimental design. Based on the results, the 1080 leaching from submerged baits had no demonstrable biological impacts since no specimen died.

Mardia's measure of multivariate kurtosis has been implemented in many statistical packages commonly used by social scientists. It provides important information on whether a commonly used multivariate procedure is appropriate for inference. Many statistical packages also have options for missing data. However, there is no procedure for applying Mardia's kurtosis to a data set with missing values. In this article Mardia's kurtosis is extended to a dataset with missing values. Based on the complete data counterpart, the behavior of a standardized version of the extended sample kurtosis can be described by the standard normal distribution. Analytical and Monte-Carlo studies imply that the proposed distribution description is as good as its complete data counterpart when missing variables are either missing completely at random or missing at random when observed marginals do not sit in a cluster with a restricted range. Application of this procedure is illustrated with a real data set. [ABSTRACT FROM AUTHOR]

Presents information on a study which determined the factors that influence drug abuse among adolescents. Methodology; Results; Discussion.

When analyzing cohort data, we rarely consider potential simultaneous effects of multiple time-scales on estimated survival proportions and hazard ratios. Instead, often, only one time-scale, such as time-on-study or attained age, is taken as the main time-scale and the other time-scale(s) included in the model as time-fixed covariate(s). In this simulation study, we investigate the potential bias in estimated survival proportions and hazard ratios by not modeling multiple time-scales. We simulate data with two time-scales, under various scenarios, and a binary covariate as the exposure of interest. Flexible parametric models with one time-scale were fitted to the simulated data, including the exposure variable of interest and the other time-scale as a fixed covariate. For many of our simulated scenarios, the models with one time-scale showed small bias for the survival proportions. Bias in the log hazard ratios (for the covariate of interest) was observed when there were non-proportional hazards on the second time-scale. If one is modeling only one time-scale it is advisable to include non-proportional hazards and interactions with the time-scale. Exploration of approaches to modeling multiple time-scales is outside the scope of this study. [ABSTRACT FROM AUTHOR]

If interest lies in reporting absolute measures of risk from time-to-event data then obtaining an appropriate approximation to the shape of the underlying hazard function is vital. It has previously been shown that restricted cubic splines can be used to approximate complex hazard functions in the context of time-to-event data. The degree of complexity for the spline functions is dictated by the number of knots that are defined. We highlight through the use of a motivating example that complex hazard function shapes are often required when analysing time-to-event data. Through the use of simulation, we show that provided a sufficient number of knots are used, the approximated hazard functions given by restricted cubic splines fit closely to the true function for a range of complex hazard shapes. The simulation results also highlight the insensitivity of the estimated relative effects (hazard ratios) to the correct specification of the baseline hazard. [ABSTRACT FROM AUTHOR]

Non-proportional hazards are common within time-to-event data and can be modeled using restricted cubic splines in flexible parametric survival models. This simulation study assesses the ability of these models in capturing non-proportional hazards, and the ability of the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) in selecting degrees of freedom. The simulation results for scenarios with differing complexities showed little bias in the survival and hazard functions for simple scenarios; bias increased in complex scenarios when fewer degrees of freedom were modeled. Neither AIC nor BIC consistently performed better and both generally selected models with little bias. [ABSTRACT FROM AUTHOR]

Road accidents and falls often result in injury to the dominant hand; however, few studies have evaluated whether the use of the nondominant hand confounds pen and paper assessments. This study used a counterbalanced within-subjects design to assess the copy accuracy on the Rey Complex Figure Test (RCFT) of 154 undergraduates using both their right and left hands. Handedness was determined using Briggs and Nebes's (1975) revision of Annett's Handedness Questionnaire. Two independent scorers used objective scoring criteria (Meyers & Meyers, 1995) with high interscorer reliability. Performance differences were statistically but not clinically significant. Nondominant- and dominant-hand performances did not differ from normative data: A total of 78.9% scored above the impairment cutoff score using the nondominant hand compared to 83.7% using their dominant hand. In the event an individual's dominant hand is compromised, performance using the nondominant hand on the RCFT could produce scores within the normative range and would not falsely suggest neuropsychological impairment. [ABSTRACT FROM AUTHOR]

This study investigated the safety of mobilising acutely ill in-patients, in particular the effect of mobilisation on their haemodynamic and respiratory parameters. Thirty one patients in an intensive care unit (ICU) deemed suitable for mobilisation, based on a comprehensive screening process, received 69 mobilisation treatments in total. These treatments most often included sitting on the edge of the bed and standing. Outcome measures including heart rate, systolic and diastolic blood pressure, and percutaneous saturation of oxygen, were measured prior to, during and after mobilisation. Additionally, any deterioration in clinical status, and intervention required for it, was noted. On the majority of occasions (91.3%), pre-treatment data from patients indicated marginal cardiac and/or respiratory reserve. During mobilisation, significant increases were seen in heart rate and blood pressure, while percutaneous oxygen saturation decreased (not significantly). These changes were generally of small magnitude and did not require any specific intervention. On three of the 69 occasions of mobilisation (4.3%), clinical status deteriorated, requiring intervention. For all three patients involved, this was a fall in oxygen saturation, requiring a temporary increase in the inspired fraction of oxygen to stabilise respiratory status. Although mobilisation resulted in significant increases in heart rate and blood pressure and a non-significant fall in percutaneous oxygen saturation, the ICU patients in this study deemed suitable for mobilisation were able to be safely mobilised. [ABSTRACT FROM AUTHOR]

Objective - To assess the effectiveness of feedback on the number of pathology tests ordered by general practices. Design - Randomised controlled trial. Setting - General practices in two primary care groups in Leicestershire, UK. Subjects - 58 general practitioners in 17 practices received guidelines then feedback at 3-month intervals for 1 year about the numbers of thyroid function, rheumatoid factor tests and urine cultures they ordered, and 38 general practitioners in 16 practices received guidelines then feedback about lipid and plasma viscosity tests. Main outcome measures - Numbers of tests requested per thousand patients registered with each practice. Results - There were no changes in the numbers of tests per thousand requested in either of the study groups for any of the tests. Conclusions - Feedback did not have an influence on test ordering by general practitioners in this study. More intensive strategies may be required to change the use of laboratory tests. [ABSTRACT FROM AUTHOR]

Objective. To determine the accuracy of the DCA® 2000 albumin/creatinine ratio urinanalyzer (Bayer Corp., Elkhart, IN) in uncomplicated pregnancy and preeclampsia. Methods. This was a prospective observational study in a large teaching maternity hospital. Ninety one uncomplicated pregnant women and 100 women referred for assessment of de novo hypertension in pregnancy had albumin concentrations, creatinine concentrations, and albumin/creatinine ratios (ACR) compared between the DCA 2000 and the laboratory gold standard assays (Dade Dimension® clinical chemistry autoanalyzer), for both early morning urines (EMU) and 24-hr urine collections. Results. The inter-assay and intra-assay variability for the DCA 2000 were less than 5.1%. In uncomplicated pregnancy the mean difference in ACR between the DCA 2000 and the laboratory assay was 0.08 mg/mmol (SD 0.28; 95% limits of agreement, -0.47, 0.63) for EMU and 0.06 (SD 0.23; 95% limits of agreement, -0.39, 0.51) for 24-hr samples. In the hypertensive cohort the ACR mean differences were -0.82 (SD 7.13; 95% limits of agreement, -14.79, 13.15) for EMU and -0.76 (SD 4.14; 95% limits of agreement, -8.87, 7.35) for 24-hr samples. The mean differences between assays in the hypertensive group had broader 95% limits of agreement due to greater variability in the samples with high albumin concentrations (> 40 mg/L). Conclusions. The DCA 2000 is accurate for the measurement of albumin creatinine ratios in the uncomplicated pregnant population. In the hypertensive population the DCA 2000 remains accurate though when the albumin concentration is greater than 40 mg/L the 95% limits of agreement are broader. We would recommend that all other automated urinalysis devices be validated by similar protocols to allow meaningful comparisons of accuracy. [ABSTRACT FROM AUTHOR]

Objective: Elevated bone turnover observed in ALS patients suggests poor bone health and increased fracture risk. We therefore evaluated the relationship of fracture to subsequent ALS risk. Methods: We followed 4,529,460 Swedes from 1987 to 2010 and identified ALS and fractures from the Swedish National Patient Register. We examined associations of ALS risk with all fractures, osteoporotic and non-osteoporotic fractures, and traumatic and non-traumatic fractures among individuals aged 30–80 years. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). We analysed the association of ALS with time since fracture using a Poisson regression model. Results: All fractures (HR: 1.51, 95% CI 1.39–1.65) as well as osteoporotic (HR: 1.59, 95% CI 1.41–1.79), non-osteoporotic (HR: 1.46, 95% CI 1.31–1.63), traumatic (HR: 1.50, 95% CI 1.37–1.63), and non-traumatic (HR: 1.80, 95% CI 1.35–2.40) fractures were associated with a higher incidence of ALS. Increased ALS incidence was associated with fractures occurring from one (HR: 2.33, 95% CI 2.04–2.66) to 18 (HR: 1.19, 95% CI 1.01–1.43) years before ALS diagnosis. Conclusions: Poor bone health may be related to ALS. These findings may offer insight into ALS pathophysiology. [ABSTRACT FROM PUBLISHER]

Objective. To determine what threshold for proteinuria could best predict clinical outcome and whether this threshold could be applied universally to any biochemical assay. Design. A prospective observational study of hypertensive pregnancies referred for further assessment after in a UK University hospital (n = 197). Twenty-four hour urine protein was measured by two different assays [benzethonium chloride assay (BCA) and Bradford assay]. The differences between the two assays were calculated from Receiver Operating Characteristic (ROC) curves. Commonly used thresholds for defining preeclampsia (0.3 and 0.5 g/24 hours) were explored for both assays for the prediction of adverse clinical outcomes (severe hypertension, Birthweight 300 mg/24 hour proteinuria and, hence, the prevalence of preeclampsia differed between the two assays. ROC curve analysis demonstrates that the two assays are similar in terms of overall performance as predictive tests. However the threshold of 300 mg/24 hours performs poorly as a predictor of clinical risk. Likelihood ratios (LR) for the BCA at the 300 mg/L threshold for each clinical outcome do not achieve statistical significance. At the 500 mg/L threshold, the LR + for the BCA assay does achieve statistical significance for severe hypertension (LR + : 1.51 95% CI 0.99–2.28) and for birthweight [ABSTRACT FROM AUTHOR]

Although the human papillomavirus (HPV) E7 oncogene is known to contribute to the development of human cervical cancer, the mechanisms of its carcinogenesis are poorly understood. The first identified and most recognized function of E7 is its binding to and inactivation of the retinoblastoma tumor suppressor (pRb), but at least 18 other biological activities have also been reported for E7. Thus, it remains unclear which of these many activities contribute to the oncogenic potential of E7. We used a Cre-lox system to abolish pRb expression in the epidermis of transgenic mice and compared the outcome with the effects of E7 expression in the same tissue at early ages. Mice lacking pRb in epidermis showed epithelial hyperplasia, aberrant DNA synthesis, and improper differentiation. In addition, Rb-deleted epidermis (i.e., epidermis composed of cells with Rb deleted) exhibited centrosomal abnormalities and failed to arrest the cell cycle in response to ionizing radiation. Transgenic mice expressing E7 in skin display the same range of phenotypes. In sum, few differences were detected between Rb-deleted epidermis and E7-expressing epidermis in young mice. However, when both E7 was expressed and Rb was deleted in the same tissue, increased hyperplasia and dysplasia were observed. These findings indicate that inactivation of the Rb pathway can largely account for E7's phenotypes at an early age, but that pRb-independent activities of E7 are detectable in vivo. [ABSTRACT FROM AUTHOR]

The roles of PDZ domain-containing proteins such as Dig and Scrib have been well described for Drosophila; however, their requirement for mammalian development is poorly understood. Here we show that Dlg, Scrib, MAGI1, MAGI3, and MPDZ are expressed in the mouse ocular lens. We demonstrate that the increase in proliferation and defects in cellular adhesion and differentiation observed in epithelia of lenses that express E6, a viral oncoprotein that can bind to several PDZ proteins, including the human homologs of Dig and Scrib, is dependent on E6's ability to bind these proteins via their PDZ domains. Analyses of lenses from mice carrying an insertional mutation in Dig (dlg[sup gt]) show increased proliferation and proliferation in spatially inappropriate regions of the lens, a phenotype similar to that of lenses expressing E6. The results from this study indicate that multiple PDZ domain-containing proteins, including Dig and Scrib, may be required for maintaining the normal pattern of growth and differentiation in the lens. Furthermore, the phenotypic similarities among the Drosophila dig mutant, the lenses of dig[sup gt] mice, and the lenses of E6 transgenic mice suggest that Dig may have a conserved function in regulating epithelial cell growth and differentiation across species. [ABSTRACT FROM AUTHOR]

Objective: To assess how urine concentration and biochemical assay influence the assessment of proteinuria. Methods: This was a prospective study to assess the accuracy of detection and quantification of proteinuria within the day assessment unit and antenatal ward of a teaching hospital in Leicester, United Kingdom. We studied hypertensive pregnancies (of mixed parity) referred to day care assessment or attending the antenatal hypertension clinic after 20 completed weeks of gestation (n = 197). Aliquots of a well-mixed 24-h urine collection were tested by routine dipstick urinalysis and then assayed for protein using the Benzethonium Chloride and the Bradford assays (n = 197). Main Outcome Measures: Total protein excretion in 24 h and protein concentration per liter of urine for both biochemical assays were compared to semiquantitative dipstick protein measurement. Results: The prevalence of proteinuria in the study group varied according to the method used for testing. Dipstick urinalysis recorded the lowest prevalence (16.2%) and the Benzethonium Chloride assay measuring total protein excretion in 24 h recorded the highest (70.1%). When the positive and negative predictive values for dipstick urinalysis were calculated, performance was found to be dependent on both the units of measurement compared and the type of assay used as the "gold standard." Positive predictive values ranged from 87.5% to 96.9% and negative predictive values ranged from 35.2% to 92.1%. Conclusions: The prevalence of proteinuria in hypertensive pregnancies is dependent on the method used to detect it. The amount of protein assessed quantitatively is further dependent on the biochemical assay employed. However, regardless of the quantitative assessment, dipstick urinalysis has a significant false-negative rate. This first reporting of a variation in performance between dipstick urinalysis and two different biochemical assays in pregnancy may be explained in relation to protein assay... [ABSTRACT FROM AUTHOR]

Since inactivation of tumor suppressor p53 functions is one of the most common features of human cancer cells, restoring p53 expression and activity is an important focus in cancer therapy. Here we report identification of photoreceptor-specific nuclear receptor (PNR)/ NR2E3 as a positive regulator of p53 in a high-throughput genetic screen. In HeLa cells, PNR stimulated p53-responsive promoters in a p53-dependent fashion and induced apoptosis in several cell types. PNR also increased p53 protein stability and specific activity as a transcriptional activator. Our studies of the underlying mechanisms showed that PNR forms complexes with p53 and the acetyltransferase p300, stimulates p53 acetylation, and increases the expression of a subset of p53 target genes. Furthermore, PNR significantly boosted actinomycin D-stimulated p53 acetylation. The unique mechanisms by which PNR stimulates p53 acetylation and functions define this orphan nuclear receptor as a potentially valuable target and tool in p53-associated cancer therapy and offer new insights into the roles of PNR mutation in retinal diseases. [ABSTRACT FROM AUTHOR]