1,444 research outputs found
The Design of a System for Online Psychosocial Care: Balancing Privacy and Accountability in Sensitive Online Healthcare Environments
The design of sensitive online healthcare systems must balance the requirements of privacy and accountability for the good of individuals, organizations, and society. Via a design science research approach, we build and evaluate a sophisticated software system for the online provision of psychosocial healthcare to distributed and vulnerable populations. Multidisciplinary research capabilities are embedded within the system to investigate the effectiveness of online treatment protocols. Throughout the development cycles of the system, we build an emergent design theory of scrutiny that applies a multi-layer protocol to support governance of privacy and accountability in sensitive online applications. The design goal is to balance stakeholder privacy protections with the need to provide for accountable interventions in critical and well-defined care situations. The research implications for the development and governance of online applications in numerous privacy-sensitive application areas are explore
Physical activity, overweight and central adiposity in Swedish children and adolescents: the European Youth Heart Study
BACKGROUND:
The aim of this work was to study the associations of physical activity (PA) and other factors predisposing to overweight, with overweight and central adiposity in children and adolescents.
METHODS:
A total of 557 Swedish children (9.5 +/- 0.3 y) and 517 adolescents (15.6 +/- 0.4 y) from the European Youth Heart Study participated in this study. Logistic regression analyses were used to examine the associations of PA, as measured by accelerometry, and other determinants (i.e. television viewing, birth weight, maternal educational level and parental overweight) with total and central adiposity. Body mass index and waist circumference cut-off values proposed by the IOTF and the Bogalusa Heart Study (i.e. waist measures for predicting risk factors clustering, hereinafter called high-risk waist circumference), respectively, were used. Fatness was estimated from skinfold thicknesses and dichotomized using the 85th sex- and age-specific percentile (high/low).
RESULTS:
Children and adolescents who had a low level (first tertile) of vigorous PA, were more likely to be overweight (including obesity) and to have a high-risk waist circumference, than those with a high level (third tertile) of vigorous PA. Similarly, those subjects who had a low or middle level (second tertile) of total PA were more likely to be overweight than those who had a high level of total PA. Among the PA variables, only vigorous PA was associated with high total fatness. Birth weight and television viewing, were also associated with higher odds of having a high-risk waist circumference, but these associations were attenuated once either total or vigorous PA variable was included in the model. Those subjects who had two overweight parents were more likely to be overweight and to have a high-risk waist circumference independently of PA variables, compared to those whose parents were not overweight.
CONCLUSION:
Low levels of total PA and especially vigorous PA may play an important role in the development of overweight and excess of central adiposity in children and adolescents, independently of a number of factors such as television viewing and birth weight. In addition, the data suggest that the association between television viewing and central fat deposition could be attenuated if enough vigorous PA is accumulated. Longitudinal and intervention studies are needed to confirm these findings.This study was supported by grants from the Stockholm County Council. FBO and JRR were supported by grants from the Consejo Superior de Deportes (109/UPB31/03, 13/UPB20/04), Ministerio de Educación y Ciencia de España (AP2003-2128, AP2004-2745), EU DG Sanco, project ALPHA (2006120), and the Margit and Folke Pehrzon Foundation
Enhancement of power system transient stability using superconducting fault current limiters
Transient stability investigations consist of studying the rotor oscillations of generators (electro-mechanic oscillations, 0.1-2 Hz) after the occurrence of a fault of large amplitude, e.g. short circuit. The goal is to indicate if the generators are capable to stay synchronous after a fault has occurred. The fault duration is one of the most important factors to be determined. In fact, the shorter the fault, the more the maintaining of synchronisation can be guaranteed. Now in case of a fault, a fault current limiter has an extremely fast current transition in comparison to electro-mechanic time constants. This implies a quasi-instantaneous elimination of the fault through a limitation of the current and consequently a better ability to maintain the synchronisation of the system. We recall that in a classic system, the elimination of a fault, by opening a circuit breaker, is carried out in two or three cycles in the best case. We have here studied a simple, radial electric network configuration with a machine and an infinite network. The study covers simulations of a fault that can occur in a network and the consequences of the recovery time of the fault current limiter
Association between muscular strength and mortality in men: prospective cohort study
Objective: To examine prospectively the association between muscular strength and mortality from all causes, cardiovascular disease, and cancer in men.
Design: Prospective cohort study.
Setting: Aerobics center longitudinal study.
Participants: 8762 men aged 20-80.
Main outcome measures: All cause mortality up to 31 December 2003; muscular strength, quantified by combining one repetition maximal measures for leg and bench presses and further categorised as age specific thirds of the combined strength variable; and cardiorespiratory fitness assessed by a maximal exercise test on a treadmill.
Results: During an average follow-up of 18.9 years, 503 deaths occurred (145 cardiovascular disease, 199 cancer). Age adjusted death rates per 10,000 person years across incremental thirds of muscular strength were 38.9, 25.9, and 26.6 for all causes; 12.1, 7.6, and 6.6 for cardiovascular disease; and 6.1, 4.9, and 4.2 for cancer (all P
Conclusion: Muscular strength is inversely and independently associated with death from all causes and cancer in men, even after adjusting for cardiorespiratory fitness and other potential confounders
The short-term plasticity of VIP interneurons in motor cortex
Short-term plasticity is an important feature in the brain for shaping neural dynamics and for information processing. Short-term plasticity is known to depend on many factors including brain region, cortical layer, and cell type. Here we focus on vasoactive-intestinal peptide (VIP) interneurons (INs). VIP INs play a key disinhibitory role in cortical circuits by inhibiting other IN types, including Martinotti cells (MCs) and basket cells (BCs). Despite this prominent role, short-term plasticity at synapses to and from VIP INs is not well described. In this study, we therefore characterized the short-term plasticity at inputs and outputs of genetically targeted VIP INs in mouse motor cortex. To explore inhibitory to inhibitory (I → I) short-term plasticity at layer 2/3 (L2/3) VIP IN outputs onto L5 MCs and BCs, we relied on a combination of whole-cell recording, 2-photon microscopy, and optogenetics, which revealed that VIP IN→MC/BC synapses were consistently short-term depressing. To explore excitatory (E) → I short-term plasticity at inputs to VIP INs, we used extracellular stimulation. Surprisingly, unlike VIP IN outputs, E → VIP IN synapses exhibited heterogeneous short-term dynamics, which we attributed to the target VIP IN cell rather than the input. Computational modeling furthermore linked the diversity in short-term dynamics at VIP IN inputs to a wide variability in probability of release. Taken together, our findings highlight how short-term plasticity at VIP IN inputs and outputs is specific to synapse type. We propose that the broad diversity in short-term plasticity of VIP IN inputs forms a basis to code for a broad range of contrasting signal dynamics
Data from a pooled post hoc analysis of 14 placebo-controlled, dapagliflozin treatment studies in patients with type 2 diabetes with and without anemia at baseline
Dapagliflozin is a highly selective sodium-glucose cotransporter 2 inhibitor associated with stabilization of estimated glomerular filtration rate (eGFR); reductions in glycated hemoglobin (HbA1c), systolic blood pressure, body weight, and albuminuria; and a small and consistent increase in hematocrit [1], [2], [3], [4]. This data set is based on the associated article [5] analyzing data from 5325 patients with type 2 diabetes from 14 placebo-controlled, phase 3 (one phase 2/3), double-blind dapagliflozin treatment studies of 24-104 weeks' duration. Data on dapagliflozin's effects (vs. placebo) on hemoglobin (Hb), hematocrit, serum albumin, serum total protein concentrations, urine albumin/creatinine ratio, eGFR, heart rate, blood pressure, body weight, and safety in patients with type 2 diabetes with and without anemia were pooled and analyzed. Patients were divided into two groups according to baseline Hb levels: anemia (Hb 16.5Â g/dL in men and >16.0Â g/dL in women). Because anemia commonly occurs in patients with diabetes and chronic kidney disease [6], the data can be of value to further analyze trends in relevant physiological and pathophysiological parameters
Cyclin A as a marker for prognosis and chemotherapy response in advanced breast cancer
We wanted to study cyclin A as a marker for prognosis and chemotherapy response. A total of 283 women with metastatic breast cancer were initially enrolled in a randomised multicentre trial comparing docetaxel to sequential methotrexate-fluorouracil (MF) in advanced breast cancer after anthracycline failure. Paraffin-embedded blocks of the primary tumour were available for 96 patients (34%). The proportion of cells expressing cyclin A was determined by immunohistochemistry using a mouse monoclonal antibody to human cyclin A. Response evaluation was performed according to WHO recommendations. The median cyclin A positivity of tumour cells was 14.5% (range 1.2–45.0). Cyclin A correlated statistically significantly to all other tested proliferation markers (mitotic count, histological grade and Ki-67). A high cyclin A correlated significantly to a shorter time to first relapse, risk ratio (RR) 1.94 (95% CI 1.24–3.03) and survival from diagnosis, RR 2.49 (95% CI 1.45–4.29), cutoff point for high/low proliferation group 10.5%. Cyclin A did not correlate to chemotherapy response or survival after anthracycline, docetaxel or MF therapy. Of all tumour biological factors tested (mitotic count, histological grade and Ki-67), cyclin A seemed to have the strongest prognostic value. Cyclin A is a good marker for tumour proliferation and prognosis in breast cancer. In the present study, cyclin A did not predict chemotherapy response
A comparison of manual neuronal reconstruction from biocytin histology or 2-photon imaging: morphometry and computer modeling.
Accurate 3D reconstruction of neurons is vital for applications linking anatomy and physiology. Reconstructions are typically created using Neurolucida after biocytin histology (BH). An alternative inexpensive and fast method is to use freeware such as Neuromantic to reconstruct from fluorescence imaging (FI) stacks acquired using 2-photon laser-scanning microscopy during physiological recording. We compare these two methods with respect to morphometry, cell classification, and multicompartmental modeling in the NEURON simulation environment. Quantitative morphological analysis of the same cells reconstructed using both methods reveals that whilst biocytin reconstructions facilitate tracing of more distal collaterals, both methods are comparable in representing the overall morphology: automated clustering of reconstructions from both methods successfully separates neocortical basket cells from pyramidal cells but not BH from FI reconstructions. BH reconstructions suffer more from tissue shrinkage and compression artifacts than FI reconstructions do. FI reconstructions, on the other hand, consistently have larger process diameters. Consequently, significant differences in NEURON modeling of excitatory post-synaptic potential (EPSP) forward propagation are seen between the two methods, with FI reconstructions exhibiting smaller depolarizations. Simulated action potential backpropagation (bAP), however, is indistinguishable between reconstructions obtained with the two methods. In our hands, BH reconstructions are necessary for NEURON modeling and detailed morphological tracing, and thus remain state of the art, although they are more labor intensive, more expensive, and suffer from a higher failure rate due to the occasional poor outcome of histological processing. However, for a subset of anatomical applications such as cell type identification, FI reconstructions are superior, because of indistinguishable classification performance with greater ease of use, essentially 100% success rate, and lower cost
Tumour microvessel density as predictor of chemotherapy response in breast cancer patients
The aim of this study was to evaluate the predictive value of intratumoural microvessel density in breast cancer. We studied immunohistochemically primary tumours of 104 patients with metastasised breast cancer who took part in a randomised multicentre trial comparing docetaxel to sequential methotrexate and 5-fluorouracil. Vessels were highlighted with factor VIII staining and counted microscopically. Microvessel density was compared with clinical response to chemotherapy and patient survival. The microvessel density of the primary tumour was not significantly associated with patient's response to chemotherapy, time to progression or overall survival in the whole patient population or in the docetaxel or methotrexate and 5-fluorouracil groups. However, disease-free survival was longer in patients with low microvessel density (P=0.01). These findings suggest that microvessel density of the primary tumour cannot be used as a predictive marker for chemotherapy response in advanced breast cancer
- …