Binary credal classification under sparsity constraints.

Binary classification is a well known problem in statistics. Besides classical methods, several techniques such as the naive credal classifier (for categorical data) and imprecise logistic regression (for continuous data) have been proposed to handle sparse data. However, a convincing approach to the classification problem in high dimensional problems (i.e., when the number of attributes is larger than the number of observations) is yet to be explored in the context of imprecise probability. In this article, we propose a sensitivity analysis based on penalised logistic regression scheme that works as binary classifier for high dimensional cases. We use an approach based on a set of likelihood functions (i.e. an imprecise likelihood, if you like), that assigns a set of weights to the attributes, to ensure a robust selection of the important attributes, whilst training the model at the same time, all in one fell swoop. We do a sensitivity analysis on the weights of the penalty term resulting in a set of sparse constraints which helps to identify imprecision in the dataset

Critical Early Roles for col27a1a and col27a1b in Zebrafish Notochord Morphogenesis, Vertebral Mineralization and Post-embryonic Axial Growth

Fibrillar collagens are well known for their links to human diseases, with which all have been associated except for the two most recently identified fibrillar collagens, type XXIV collagen and type XXVII collagen. To assess functions and potential disease phenotypes of type XXVII collagen, we examined its roles in zebrafish embryonic and post-embryonic development.We identified two type XXVII collagen genes in zebrafish, col27a1a and col27a1b. Both col27a1a and col27a1b were expressed in notochord and cartilage in the embryo and early larva. To determine sites of type XXVII collagen function, col27a1a and col27a1b were knocked down using morpholino antisense oligonucleotides. Knockdown of col27a1a singly or in conjunction with col27a1b resulted in curvature of the notochord at early stages and formation of scoliotic curves as well as dysmorphic vertebrae at later stages. These defects were accompanied by abnormal distributions of cells and protein localization in the notochord, as visualized by transmission electron microscopy, as well as delayed vertebral mineralization as detected histologically.Together, our findings indicate a key role for type XXVII collagen in notochord morphogenesis and axial skeletogenesis and suggest a possible human disease phenotype

Radiotherapy in the treatment of Graves ophthalmopathy—to do it or not?

To the objective of this study is to evaluate the role and toxicity of radiotherapy in the treatment of Graves ophthalmopathy. In the years 2000–2003, 121 patients with malignant exophthalmos were treated with radiotherapy of the retrobulbar area to the total dose of 20 Gy in ten fractions with a 6 MeV photon beam. The treatment was performed by the team of the Clinic of Oncology of the Jagiellonian University Medical College in Cracow. The radiotherapy was preceded by intravenous steroid therapy: methylprednisolone acetate administered at the dose of 2 g/week for four consecutive weeks. The highest efficacy, expressed as improvement of all ocular symptoms, was observed for the combined treatment. Female and non-diabetic patients responded positively to the combined treatment. Radiotherapy combined with steroid therapy in the treatment of Graves ophthalmopathy seems to be an effective treatment for strictly defined indications. In the treatment of Graves–Basedow disease, radiotherapy is a well-tolerated treatment modality. Diabetes is a factor that worsens prognosis in Graves ophthalmopathy and female sex is a favourable factor for this condition

New relative intensity ambulatory accelerometer thresholds for elderly men and women: the Generation 100 study

BACKGROUND: Public health initiatives world-wide recommend increasing physical activity (PA) to improve health. However, the dose and the intensity of PA producing the most benefit are still debated. Accurate assessment of PA is necessary in order to 1) investigate the dose–response relationship between PA and health, 2) shape the most beneficial public health initiatives and 3) test the effectiveness of such initiatives. Actigraph accelerometer is widely used to objectively assess PA, and the raw data is given in counts per unit time. Count-thresholds for low, moderate and vigorous PA are mostly based on absolute intensity. This leads to largely inadequate PA intensity assessment in a large proportion of the elderly, who due to their declining maximal oxygen uptake (VO(2max)) cannot reach the moderate/vigorous intensity as defined in absolute terms. To resolve this issue, here we report relative Actigraph intensity-thresholds for the elderly. METHODS: Submaximal-oxygen-uptake, VO(2max) and maximal heart rate (HR(max)) were measured in 111 70–77 year olds, while wearing an Actigraph-GT3X+. Relationship between VO(2max) percentage (%), counts-per-minute (CPM) and gender (for both the vertical-axis (VA) and vector-magnitude (VM)) and VO(2max)% and HR(max)% was established using a mixed-regression-model. VM-and VA-models were tested against each other to see which model predicts intensity of PA better. RESULTS: VO(2max) and gender significantly affected number of CPM at different PA intensities (p < 0.05). Therefore, intensity-thresholds were created for both men and women of ranging VO(2max) values (low, medium, high). VM-model was found to be a better predictor of PA-intensity than VA-model (p < 0.05). Established thresholds for moderate intensity (46−63 % of VO(2max)) ranged from 669–3367 and 834–4048 CPM and vigorous intensity (64−90 % of VO(2max)) from 1625–4868 and 2012-5423CPM, for women and men, respectively. Lastly, we used this evidence to derive a formula that predicts customized relative intensity of PA (either VO(2max)% or HR(max)%) using counts-per-minute values as input. CONCLUSION: Intensity-thresholds depend on VO(2max), gender and Actigraph-axis. PA intensity-thresholds that take all these factors into account allow for more accurate relative intensity PA assessment in the elderly and will be useful in future PA research. TRIAL REGISTRATION: (ClinicalTrials.gov Identifier: NCT02017847, registered 17. December 2013

A revised evolutionary history of the CYP1A subfamily : gene duplication, gene conversion, and positive selection

Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Journal of Molecular Evolution 62 (2006): 708-717, doi:10.1007/s00239-005-0134-z.Members of cytochrome P450 subfamily 1A (CYP1As) are involved in detoxification and bioactivation of common environmental pollutants. Understanding the functional evolution of these genes is essential to predicting and interpreting species differences in sensitivity to toxicity by such chemicals. The CYP1A gene subfamily comprises a single ancestral representative in most fish species and two paralogs in higher vertebrates, including birds and mammals. Phylogenetic analysis of complete coding sequences suggests that mammalian and bird paralog pairs (CYP1A1/2 and CYP1A4/5, respectively) are the result of independent gene duplication events. However, comparison of vertebrate genome sequences revealed that CYP1A genes lie within an extended region of conserved fine-scale synteny, suggesting that avian and mammalian CYP1A paralogs share a common genomic history. Algorithms designed to detect recombination between nucleotide sequences indicate that gene conversion has homogenized most of the length of the chicken CYP1A genes, as well as the 5’ end of mammalian CYP1As. Together, these data indicate that avian and mammalian CYP1A paralog pairs resulted from a single gene duplication event and that extensive gene conversion is responsible for the exceptionally high degree of sequence similarity between CYP1A4 and CYP1A5. Elevated non-synonymous/synonymous substitution ratios within a putatively unconverted stretch of ~250 bp suggests that positive selection may have reduced the effective rate of gene conversion in this region, which contains two substrate recognition sites. This work significantly alters our understanding of functional evolution in the CYP1A subfamily, suggesting that gene conversion and positive selection have been the dominant processes of sequence evolution.Funding for this work was provided by the NIH Superfund Basic Research Program at Boston University (5-P42-ES-07381) and by the Woods Hole Oceanographic Institution

Peer-Victimization and Mental Health Problems in Adolescents: Are Parental and School Support Protective?

The aim of this study was to investigate the frequency and effects of peer-victimization on mental health problems among adolescents. Parental and school support were assumed as protective factors that might interact with one another in acting as buffers for adolescents against the risk of peer-victimization. Besides these protective factors, age and gender were additionally considered as moderating factors. The Social and Health Assessment survey was conducted among 986 students aged 11–18 years in order to assess peer-victimization, risk and protective factors and mental health problems. For mental health problems, the Strengths and Difficulties Questionnaire (SDQ) was used. Effects of peer-victimization on mental health problems were additionally compared with normative SDQ data in order to obtain information about clinically relevant psychopathology in our study sample. Results of this study show that peer-victimization carries a serious risk for mental health problems in adolescents. School support is effective in both male and female adolescents by acting as a buffer against the effect of victimization, and school support gains increasing importance in more senior students. Parental support seems to be protective against maladjustment, especially in peer-victimized girls entering secondary school. Since the effect of peer-victimization can be reduced by parental and school support, educational interventions are of great importance in cases of peer-victimization

Hyperspectral Computed Tomographic Imaging Spectroscopy of Vascular Oxygen Gradients in the Rabbit Retina In Vivo

Diagnosis of retinal vascular diseases depends on ophthalmoscopic findings that most often occur after severe visual loss (as in vein occlusions) or chronic changes that are irreversible (as in diabetic retinopathy). Despite recent advances, diagnostic imaging currently reveals very little about the vascular function and local oxygen delivery. One potentially useful measure of vascular function is measurement of hemoglobin oxygen content. In this paper, we demonstrate a novel method of accurately, rapidly and easily measuring oxygen saturation within retinal vessels using in vivo imaging spectroscopy. This method uses a commercially available fundus camera coupled to two-dimensional diffracting optics that scatter the incident light onto a focal plane array in a calibrated pattern. Computed tomographic algorithms are used to reconstruct the diffracted spectral patterns into wavelength components of the original image. In this paper the spectral components of oxy- and deoxyhemoglobin are analyzed from the vessels within the image. Up to 76 spectral measurements can be made in only a few milliseconds and used to quantify the oxygen saturation within the retinal vessels over a 10–15 degree field. The method described here can acquire 10-fold more spectral data in much less time than conventional oximetry systems (while utilizing the commonly accepted fundus camera platform). Application of this method to animal models of retinal vascular disease and clinical subjects will provide useful and novel information about retinal vascular disease and physiology

Subjective Distresses of Nasogastric Tube Feeding

Health care professionals assume that tube feeding is an unpleasant, distressing experience for patients, which is only partially substantiated by experience. Thirty patients were interviewed via a tube feeding and hospital experience checklist (a 47–item interview schedule). Common experiences were operationally defined as those felt by at least 50%; subjectively distressful experiences were those identified by patients as causing distress. The most common and most distressful experiences of nasogastric tube feeding were: sensory irritations and sensory deprivation. The psychosensory irritation experiences were: thirst, sore nose or throat, dry mouth, runny nose, a tube in the nose, taking food through a tube, breathing through the mouth, breathing with a tube in the nose, taking food in a treatment type container, and taking food with a different texture and smell than usual. The psychosensory deprivation experiences were: an unsatisfied appetite for certain foods, deprivation of tasting, chewing, swallowing food, and drinking liquids, limited mobility, and deprivation of regular food. Except for burping, gastrointestinal symptoms were not common though they were usually distressful. This information has been used to develop teaching programs which are being tested for effectiveness in reducing distress associated with nasogastric tube feeding.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68702/2/10.1177_014860717900300204.pd

The IGNITE (investigation to guide new insight into translational effectiveness) trial: Protocol for a translational study of an evidenced-based wellness program in fire departments

<p>Abstract</p> <p>Background</p> <p>Worksites are important locations for interventions to promote health. However, occupational programs with documented efficacy often are not used, and those being implemented have not been studied. The research in this report was funded through the American Reinvestment and Recovery Act Challenge Topic 'Pathways for Translational Research,' to define and prioritize determinants that enable and hinder translation of evidenced-based health interventions in well-defined settings.</p> <p>Methods</p> <p>The IGNITE (investigation to guide new insights for translational effectiveness) trial is a prospective cohort study of a worksite wellness and injury reduction program from adoption to final outcomes among 12 fire departments. It will employ a mixed methods strategy to define a translational model. We will assess decision to adopt, installation, use, and outcomes (reach, individual outcomes, and economic effects) using onsite measurements, surveys, focus groups, and key informant interviews. Quantitative data will be used to define the model and conduct mediation analysis of each translational phase. Qualitative data will expand on, challenge, and confirm survey findings and allow a more thorough understanding and convergent validity by overcoming biases in qualitative and quantitative methods used alone.</p> <p>Discussion</p> <p>Findings will inform worksite wellness in fire departments. The resultant prioritized influences and model of effective translation can be validated and manipulated in these and other settings to more efficiently move science to service.</p