944 resultados para RIGHT-CENSORED DATA
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Hearings held on S. 3418, 3633, 3116, 2810, and 2542.
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This report summarizes the data, observations, methods, assumptions, and decisions for the design of the Relief Well Rehabilitation Project in the Right Abutment Drainage Tunnel at Chief Joseph Dam. Chief Joseph Dam (CJD) is a dam on the Columbia River and is owned and operated by the U.S. Army Corps of Engineers (USACE). It is the second only to Grand Coulee dam as the largest producer of hydropower in the United States. The right abutment drainage tunnel contains wooden stave relief wells. Water flows from these wells which reduces the hydrostatic pressure in the right abutment of the dam. The 22 wells in the floor of the tunnel are 60 years old and are in need of rehabilitation. The objective of this project is to control the groundwater gradient, prevent the movement of sediment, stop total screen collapse, and prevent initiation of backwards erosion and piping in the abutment. The rehabilitation solution is to install new stainless steel screens into the existing wells, backfill the annular space between the old wooden screen and the new stainless steel screens with a 3/8-inch pea gravel filter pack, and install a new top cap to hold the new screen in place. This report documents the data, observations, and methods used to complete the final design. During tunnel inspections USACE geologists observed dislodged end plugs and evidence of sediment movement out of the formation. The relief wells have historically high flows between 6,000 gallons per minute (gpm) to 9,000 gpm. New screens are designed based on as-built data and historic tunnel flow. The new screens are 8-in diameter, 100 slot (0.10-inch) screens. We found that screen diameter and slot size would provide adequate transmitting capacity for most of the relief wells. The filter pack gradation is based on descriptions from foundation construction reports. I found that 3/8-inch pea gravel is appropriate for the abutment material. During design, I also considered an option to install the screens into the relief wells without filter pack. I eliminated this option because it did not meet our rehabilitation objective to prevent total failure of the wooden screens.
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In disorders such as sleep apnea, sleep is fragmented with frequent EEG-arousal (EEGA) as determined via changes in the sleep-electroencephalogram. EEGA is a poorly understood, complicated phenomenon which is critically important in studying the mysteries of sleep. In this paper we study the information flow between the left and right hemispheres of the brain during the EEGA as manifested through inter-hemispheric asynchrony (IHA) of the surface EEG. EEG data (using electrodes A1/C4 and A2/C3 of international 10-20 system) was collected from 5 subjects undergoing routine polysomnography (PSG). Spectral correlation coefficient (R) was computed between EEG data from two hemispheres for delta-delta(0.5-4 Hz), theta-thetas(4.1-8 Hz), alpha-alpha(8.1-12 Hz) & beta-beta(12.1-25 Hz) frequency bands, during EEGA events. EEGA were graded in 3 levels as (i) micro arousals (3-6 s), (ii) short arousals (6.1-10 s), & (iii) long arousals (10.1-15 s). Our results revealed that in beta band, IHA increases above the baseline after the onset of EEGA and returns to the baseline after the conclusion of event. Results indicated that the duration of EEGA events has a direct influence on the onset of IHA. The latency (L) between the onset of arousals and IHA were found to be L=2plusmn0.5 s (for micro arousals), 4plusmn2.2 s (short arousals) and 6.5plusmn3.6 s (long arousals)
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The 'attentional blink' (AB) reflects a limitation in the ability to identify multiple items in a stream of rapidly presented information. Repetitive transcranial magnetic stimulation (rTMS), applied to a site over the right posterior parietal cortex, reduced the magnitude of the AB to visual stimuli, whilst no effect of rTMS was found when stimulation took place at a control site. The data confirm that the posterior parietal cortex may play a critical role in temporal as well as spatial aspects of visual attention.
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Purpose - Measurements obtained from the right and left eye of a subject are often correlated whereas many statistical tests assume observations in a sample are independent. Hence, data collected from both eyes cannot be combined without taking this correlation into account. Current practice is reviewed with reference to articles published in three optometry journals, viz., Ophthalmic and Physiological Optics (OPO), Optometry and Vision Science (OVS), Clinical and Experimental Optometry (CEO) during the period 2009–2012. Recent findings - Of the 230 articles reviewed, 148/230 (64%) obtained data from one eye and 82/230 (36%) from both eyes. Of the 148 one-eye articles, the right eye, left eye, a randomly selected eye, the better eye, the worse or diseased eye, or the dominant eye were all used as selection criteria. Of the 82 two-eye articles, the analysis utilized data from: (1) one eye only rejecting data from the adjacent eye, (2) both eyes separately, (3) both eyes taking into account the correlation between eyes, or (4) both eyes using one eye as a treated or diseased eye, the other acting as a control. In a proportion of studies, data were combined from both eyes without correction. Summary - It is suggested that: (1) investigators should consider whether it is advantageous to collect data from both eyes, (2) if one eye is studied and both are eligible, then it should be chosen at random, and (3) two-eye data can be analysed incorporating eyes as a ‘within subjects’ factor.
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Using panel data pertaining to large Polish (non-financial) firms this paper examines the determinants of employment change during the period 1996-2002. Paying particular attention to the asymmetry hypothesis we investigate the impact of own wages, outside wages, output growth, regional characteristics and sectoral affiliation on the evolution of employment. In keeping with the 'right to manage' model we find that employment dynamics are not affected negatively by alternative wages. Furthermore, in contrast to the early transition period, we find evidence that employment levels respond to positive sales growth (in all but state firms). The early literature, (e.g. Kollo, 1998) found that labour hoarding lowered employment elasticities in the presence of positive demand shocks. Our findings suggest that inherited labour hoarding may no longer be a factor. We argue that the present pattern of employment adjustment is better explained by the role of insiders. This tentative conclusion is hinged on the contrasting behaviour of state and privatised companies and the similar behaviour of privatised and new private companies. We conclude that lower responsiveness of employment to both positive and negative changes in revenue in state firms is consistent with the proposition that rent sharing by insiders is stronger in the state sector.
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In many of the Statnotes described in this series, the statistical tests assume the data are a random sample from a normal distribution These Statnotes include most of the familiar statistical tests such as the ‘t’ test, analysis of variance (ANOVA), and Pearson’s correlation coefficient (‘r’). Nevertheless, many variables exhibit a more or less ‘skewed’ distribution. A skewed distribution is asymmetrical and the mean is displaced either to the left (positive skew) or to the right (negative skew). If the mean of the distribution is low, the degree of variation large, and when values can only be positive, a positively skewed distribution is usually the result. Many distributions have potentially a low mean and high variance including that of the abundance of bacterial species on plants, the latent period of an infectious disease, and the sensitivity of certain fungi to fungicides. These positively skewed distributions are often fitted successfully by a variant of the normal distribution called the log-normal distribution. This statnote describes fitting the log-normal distribution with reference to two scenarios: (1) the frequency distribution of bacterial numbers isolated from cloths in a domestic environment and (2), the sizes of lichenised ‘areolae’ growing on the hypothalus of Rhizocarpon geographicum (L.) DC.
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This article discusses implications of participant withdrawal for inductive research. I describe and analyze how a third of my participants withdrew from a grounded theory study. I position my example, ensuing issues, and potential solutions as reflective of inductive methodologies as a whole. The crux of the problem is the disruption inflicted by withdrawal on inductive processes of generating knowledge. I examine the subsequent methodological and ethical issues in trying to determine the best course of action following withdrawal. I suggest three potential options for researchers: Continuing the study with partial data, continuing the study with all data, and discontinuing the study. Motivated by my experience, and wider theoretical considerations, I present several suggestions and questions, with the aim of supporting researchers in determining the best course of action for their individual field circumstances.
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Big data comes in various ways, types, shapes, forms and sizes. Indeed, almost all areas of science, technology, medicine, public health, economics, business, linguistics and social science are bombarded by ever increasing flows of data begging to be analyzed efficiently and effectively. In this paper, we propose a rough idea of a possible taxonomy of big data, along with some of the most commonly used tools for handling each particular category of bigness. The dimensionality p of the input space and the sample size n are usually the main ingredients in the characterization of data bigness. The specific statistical machine learning technique used to handle a particular big data set will depend on which category it falls in within the bigness taxonomy. Large p small n data sets for instance require a different set of tools from the large n small p variety. Among other tools, we discuss Preprocessing, Standardization, Imputation, Projection, Regularization, Penalization, Compression, Reduction, Selection, Kernelization, Hybridization, Parallelization, Aggregation, Randomization, Replication, Sequentialization. Indeed, it is important to emphasize right away that the so-called no free lunch theorem applies here, in the sense that there is no universally superior method that outperforms all other methods on all categories of bigness. It is also important to stress the fact that simplicity in the sense of Ockham’s razor non-plurality principle of parsimony tends to reign supreme when it comes to massive data. We conclude with a comparison of the predictive performance of some of the most commonly used methods on a few data sets.
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Aims: Previous research has identified several inadequacies in management of diabetes within care homes many of which were highlighted in Diabetes UK’s report Diabetes in care homes:awareness, screening, training. The aim of this study was to see if this was still the case and to identify specific areas for improvement. Methods: Thirty care homes in Birmingham were invited to participate in the study. Data were collected using a standard questionnaire based on the Diabetes UK national survey of care homes comprising questions relating to screening, self-management, care planning and local authority support. All returned responses were analysed. Results: Responses were received from 20 of the 30 care homes approached. The mean percentage of residents with diabetes in the care homes sampled was 13.7%. None of the homes screened for diabetes on admission and only 5% screened residents annually.80% of homes acknowledged providing diabetes-specific training to staff. Residents in 95% of homes had a medical review in the last 12 months: 70% with a GP, 20% with a diabetes specialist nurse/nurse. 65% of homes provided support for self-management.45% of care homes did not have individualised care plans for residents with diabetes. 35% of managers reported poor support and guidance from their local authority.Conclusions: Improvements were noted in the care provided to individuals with diabetes living in care homes in Birmingham. Aspects relating to screening, individualised care plans and support to care home staff still need attention.
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Although much research has examined employees’ experience of the work-family interface, its conceptualization has been rather problematic, ranging from work and family as mutually constraining through to mutually enriching and, more recently, to work-family balance (WFB). Building on Greenhaus and Allen’s (2011) conceptualization of WFB as comprising satisfaction and effectiveness components, I proposed and tested a model of he antecedents and outcomes of WFB. Based on work-family border theory, I hypothesised that family-supportive supervisor behaviours (FSSB) facilitate WFB and hat the relationship is stronger when the organisation also offers formal support (availability of family-friendly practices (FFPs); enhancement effect). Furthermore, I integrated the leadership and work-family interface literatures by proposing authentic eadership as an antecedent of FSSB. Based on role accumulation theories, I proposed life satisfaction and health as outcomes of WFB satisfaction and WFB effectiveness and job performance as an outcome of only WFB effectiveness. I tested my hypotheses with individual-level data in Study 1 (two waves of data; employees from Germany and the UK) and nested data (individuals nested in teams; two waves of data; employee and supervisor ratings; Germany and the UK) in Study 2. The obtained findings largely supported the hypothesized model and showed that both authentic leadership (Study 1) and team authentic leadership (Study 2) predicted FSSB which, in turn, increased WFB satisfaction and WFB effectiveness. Contrary to my prediction, both studies revealed that FSSB and (team) availability of FFPs compensated for each other, only impacting WFB satisfaction/effectiveness if the other form of family support was not available. Furthermore, both components were positively related to life satisfaction and health, while WFB effectiveness was only related to self-rated performance (Study 1) and not supervisor-rated performance (Study 2). Lastly, the serial moderated mediation model hat tested the conditional indirect effect of (team) authentic leadership on the outcomes received mixed support.
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This study investigated the effect of sleep position on breathing patterns of normal full term infants during quiet and active behavioral sleep states. Tidal volume, percent contribution of rib cage to tidal volume, and respiration rate were measured via respiratory inductive plethysmography (RIP) and pneumotachograph (PNT) in ten infants sleeping in supine versus right side-lying. Data was collected immediately following two consecutive feedings. Paired t tests and ANOVA comparisons showed no significant differences between the two postures (p $<$.05) in mean tidal volume (supine, M = 19.16, right side, M = 22.45), percent contribution of rib cage to tidal volume (supine, M = 30.55, right side M = 33.20), or respiration rate (supine, M = 49.13, right side, M = 49.37) during quiet sleep. Comparisons also showed no significant differences between the two postures (p $<$.05) in mean tidal volume (supine, M = 18.89, right side, M = 20.12), percent contribution of rib cage to tidal volume (supine, M = 6.43, right side, M = 6.97) or respiration rate (supine, M = 62.18, right side, M = 61.04) during active sleep. Therefore, no differences were found in the three respiratory variables measured between the supine and right side-lying positions. These findings suggest that infants may be positioned in either sleep position without detriment to respiratory function. This information may benefit occupational therapists and other health professionals involved in the education of parents on infant positioning and their respective advantages. ^
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This dissertation established a software-hardware integrated design for a multisite data repository in pediatric epilepsy. A total of 16 institutions formed a consortium for this web-based application. This innovative fully operational web application allows users to upload and retrieve information through a unique human-computer graphical interface that is remotely accessible to all users of the consortium. A solution based on a Linux platform with My-SQL and Personal Home Page scripts (PHP) has been selected. Research was conducted to evaluate mechanisms to electronically transfer diverse datasets from different hospitals and collect the clinical data in concert with their related functional magnetic resonance imaging (fMRI). What was unique in the approach considered is that all pertinent clinical information about patients is synthesized with input from clinical experts into 4 different forms, which were: Clinical, fMRI scoring, Image information, and Neuropsychological data entry forms. A first contribution of this dissertation was in proposing an integrated processing platform that was site and scanner independent in order to uniformly process the varied fMRI datasets and to generate comparative brain activation patterns. The data collection from the consortium complied with the IRB requirements and provides all the safeguards for security and confidentiality requirements. An 1-MR1-based software library was used to perform data processing and statistical analysis to obtain the brain activation maps. Lateralization Index (LI) of healthy control (HC) subjects in contrast to localization-related epilepsy (LRE) subjects were evaluated. Over 110 activation maps were generated, and their respective LIs were computed yielding the following groups: (a) strong right lateralization: (HC=0%, LRE=18%), (b) right lateralization: (HC=2%, LRE=10%), (c) bilateral: (HC=20%, LRE=15%), (d) left lateralization: (HC=42%, LRE=26%), e) strong left lateralization: (HC=36%, LRE=31%). Moreover, nonlinear-multidimensional decision functions were used to seek an optimal separation between typical and atypical brain activations on the basis of the demographics as well as the extent and intensity of these brain activations. The intent was not to seek the highest output measures given the inherent overlap of the data, but rather to assess which of the many dimensions were critical in the overall assessment of typical and atypical language activations with the freedom to select any number of dimensions and impose any degree of complexity in the nonlinearity of the decision space.
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The goal of this thesis was to develop, construct, and validate the Perceived Economic Burden scale to quantitatively measure the burden associated with a subtype Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) in families from the island of Newfoundland. An original 76 item self-administered survey was designed using content from existing literature as well as themes from qualitative research conducted by our team and distributed to individuals of families known to be at risk for the disease. A response rate of 37.2% (n = 64) was achieved between December 2013 and May 2014. Tests for data quality, Likert scale assumptions and scale reliability were conducted and provided preliminary evidence of the psychometric properties of the final constructed perceived economic burden of ARVC scale comprising 62 items in five sections. Findings indicated that being an affected male was a significant predictor of increased perceived economic burden in the majority of economic burden measures. Affected males also reported an increased likelihood of going on disability and difficulty obtaining insurance. Affected females also had an increased perceived financial burden. Preliminary results suggest that a perceived economic burden exists within the ARVC population in Newfoundland.
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Our ability to project the impact of global change on marine ecosystem is limited by our poor understanding on how to predict species sensitivity. For example, the impact of ocean acidification is highly species-specific, even in closely related taxa. The aim of this study was to test the hypothesis that the tolerance range of a given species to decreased pH corresponds to their natural range of exposure. Larvae of the green sea urchin Strongylocentrotus droebachiensis were cultured from fertilization to metamorphic competence (29 days) under a wide range of pH (from pHT = 8.0/pCO2 ~ 480 ?atm to pHT = 6.5/pCO2 ~ 20 000 ?atm) covering present (from pHT 8.7 to 7.6), projected near-future variability (from pHT 8.3 to 7.2) and beyond. Decreasing pH impacted all tested parameters (mortality, symmetry, growth, morphometry and respiration). Development of normal, although showing morphological plasticity, swimming larvae was possible as low as pHT >= 7.0. Within that range, decreasing pH increased mortality and asymmetry and decreased body length (BL) growth rate. Larvae raised at lowered pH and with similar BL had shorter arms and a wider body. Relative to a given BL, respiration rates and stomach volume both increased with decreasing pH suggesting changes in energy budget. At the lowest pHs (pHT <= 6.5), all the tested parameters were strongly negatively affected and no larva survived past 13 days post fertilization. In conclusion, sea urchin larvae appeared to be highly plastic when exposed to decreased pH until a physiological tipping point at pHT = 7.0. However, this plasticity was associated with direct (increased mortality) and indirect (decreased growth) consequences for fitness.