Subjective quality assessment of an adaptive video streaming model

With the recent increased popularity and high usage of HTTP Adaptive Streaming (HAS) techniques, various studies have been carried out in this area which generally focused on the technical enhancement of HAS technology and applications. However, a lack of common HAS standard led to multiple proprietary approaches which have been developed by major Internet companies. In the emerging MPEG-DASH standard the packagings of the video content and HTTP syntax have been standardized; but all the details of the adaptation behavior are left to the client implementation. Nevertheless, to design an adaptation algorithm which optimizes the viewing experience of the enduser, the multimedia service providers need to know about the Quality of Experience (QoE) of different adaptation schemes. Taking this into account, the objective of this experiment was to study the QoE of a HAS-based video broadcast model. The experiment has been carried out through a subjective study of the end user response to various possible clients’ behavior for changing the video quality taking different QoE-influence factors into account. The experimental conclusions have made a good insight into the QoE of different adaptation schemes which can be exploited by HAS clients for designing the adaptation algorithms.

Crowdsourcing based subjective quality assessment of adaptive video streaming

In order to cater for user's quality of experience (QoE) requirements, HTTP adaptive streaming (HAS) based solutions of video services have become popular recently. User QoE feedback can be instrumental in improving the capabilities of such services. Perceptual quality experiments that involve humans are considered to be the most valid method of the assessment of QoE. Besides lab-based subjective experiments, crowdsourcing based subjective assessment of video quality is gaining popularity as an alternative method. This paper presents insights into a study that investigates perceptual preferences of various adaptive video streaming scenarios through crowdsourcing based subjective quality assessment.

Avaliação da composição corporal e do estado nutricional em doentes com neoplasias gastrointestinais : bioimpedância elétrica e tomografia axial computorizada, que correlação?

Tese de mestrado, Nutrição Clínica, Faculdade de Medicina, Universidade de Lisboa, 2015

Impact of premorbid undernutrition on outcome in stroke patients

Background and Purpose - To assess the prevalence of premorbid undernutrition and its impact on outcomes 1 month after stroke. Methods - The study recruited from consecutive stroke admissions during a 10-month period. Premorbid nutritional status ( using the subjective global assessment [SGA]), premorbid functioning ( modified Rankin scale [MRS]), and stroke severity ( National Institutes of Health Stroke Scale [NIHSS] score) were assessed at admission. The associations between premorbid nutritional status, poor outcome ( defined as MRS greater than or equal to 3), and mortality were examined before and after adjustment for confounding variables, including age, gender, stroke risk factors, stroke severity, and admission serum albumin. Results - Thirty of 185 patients were assessed as having undernutrition at admission. Significant unadjusted associations were observed between undernutrition and poor outcome (odds ratio [OR], 3.4; 95% CI, 1.3 to 8.7; P = 0.01), and mortality (OR, 3.1, 95% CI, 1.3 to 7.7; P = 0.02) at 1 month. NIHSS, age, and premorbid MRS were also significantly associated with poor outcomes. After adjustment for these factors, the effect size of associations remained important but not significant ( poor outcome: OR, 2.4; 95% CI, 0.7 to 9.0, P = 0.18; mortality: OR, 3.2; 95% CI, 1.0 to 10.4, P = 0.05). Conclusions - Premorbid undernutrition, as assessed using the SGA, appears to be an independent predictor of poor stroke outcome. Stroke prevention strategies should target undernutrition in the population at risk for stroke to improve outcomes.

Global assessment of coral bleaching and required rates of adaptation under climate change

Elevated ocean temperatures can cause coral bleaching, the loss of colour from reef-building corals because of a breakdown of the symbiosis with the dinoflagellate Symbiodinium. Recent studies have warned that global climate change could increase the frequency of coral bleaching and threaten the long-term viability of coral reefs. These assertions are based on projecting the coarse output from atmosphere-ocean general circulation models (GCMs) to the local conditions around representative coral reefs. Here, we conduct the first comprehensive global assessment of coral bleaching under climate change by adapting the NOAA Coral Reef Watch bleaching prediction method to the output of a low- and high-climate sensitivity GCM. First, we develop and test algorithms for predicting mass coral bleaching with GCM-resolution sea surface temperatures for thousands of coral reefs, using a global coral reef map and 1985-2002 bleaching prediction data. We then use the algorithms to determine the frequency of coral bleaching and required thermal adaptation by corals and their endosymbionts under two different emissions scenarios. The results indicate that bleaching could become an annual or biannual event for the vast majority of the world's coral reefs in the next 30-50 years without an increase in thermal tolerance of 0.2-1.0 degrees C per decade. The geographic variability in required thermal adaptation found in each model and emissions scenario suggests that coral reefs in some regions, like Micronesia and western Polynesia, may be particularly vulnerable to climate change. Advances in modelling and monitoring will refine the forecast for individual reefs, but this assessment concludes that the global prognosis is unlikely to change without an accelerated effort to stabilize atmospheric greenhouse gas concentrations.

Detection of nosocomial malnutrition is improved in Amazon region by a standard clinical nutrition education program

Background: In Brazil hospital malnutrition is highly prevalent. physician awareness of malnutrition is low, and nutrition therapy is underprescribed. One alternative to approach this problem is to educate health care providers in clinical nutrition. The present study aims to evaluate the effect of an intensive education course given to health care professionals and students on the diagnosis ability concerning to hospital malnutrition. Materials and methods: An intervention study based on a clinical nutrition educational program, offered to medical and nursing students and professionals, was held in a hospital of the Amazon region. Participants were evaluated through improvement of diagnostic ability, according to agreement of malnutrition diagnosis using Subjective Global Assessment before and after the workshop, as compared to independent evaluations (Kappa Index, k). To evaluate the impact of the educational intervention on the hospital malnutrition diagnosis, medical records were reviewed for documentation of parameters associated with nutritional status of in-patients. The SPSS statistical software package was used for data analysis. Results: A total of 165 participants concluded the program. The majority (76.4%) were medical and nursing students. Malnutrition diagnosis improved after the course (before k = 0.5; after k = 0.64; p < 0.05). A reduction of false negatives from 50% to 33.3% was observed. During the course, concern of nutritional diagnosis was increased W = 17.57; p < 0.001) and even after the course, improvement on the height measurement was detected chi(2) 12.87;p < 0.001). Conclusions: Clinical nutrition education improved the ability of diagnosing malnutrition; however the primary impact was on medical and nursing students. To sustain diagnostic capacity a clinical nutrition program should be part of health professional curricula and be coupled with continuing education for health care providers.

Nutritional status and overhydration: can bioimpedance spectroscopy be useful in haemodialysis patients?

Background: Protein-energy wasting (PEW), associated with inflammation and overhydration, is common in haemodialysis (HD) patients and is associated with high morbidity and mortality. Objective: Assess the relationship between nutritional status, markers of inflammation and body composition through bioimpedance spectroscopy (BIS) in HD patients. Methods: This observational, cross-sectional, single centre study, carried out in an HD centre in Forte da Casa (Portugal), involved 75 patients on an HD programme. In all participating patients, the following laboratory tests were conducted: haemoglobin, albumin, C-reactive protein (CRP) and 25-hydroxyvitamin D3 [25(OH)D3]. The body mass index of all patients was calculated and a modified version of subjective global assessment (SGA) was produced for patients on dialysis. Intracellular water (ICW) and extracellular water (ECW) were measured by BIS (Body Composition Monitor®, Fresenius Medical Care®) after the HD session. In statistical analysis, Spearman’s correlation was used for the univariate analysis and linear regression for the multivariate analysis (SPSS 14.0). A P value of <.05 was considered statistically significant. Results: PEW, inversely assessed through the ICW/body weight (BW) ratio, was positively related to age (P<.001), presence of diabetes (P=.004), BMI (P=.01) and CRP (P=.008) and negatively related to albumin (p=.006) and 25(OH)D3 (P=.007). Overhydration, assessed directly through the ECW/BW ratio, was positively related with CRP (P=.009) and SGA (P=.03), and negatively with 25(OH)D3 (P=.006) and BMI (P=.01). In multivariate analysis, PEW was associated with older age (P<.001), the presence of diabetes (P=.003), lower 25(OH)D3 (P=.008), higher CRP (P=.001) and lower albumin levels (P=.004). Over-hydration was associated with higher CRP (P=.001) and lower levels of 25(OH)D3 (P=.003). Conclusions: Taking these results into account, the ICW/BW and ECW/BW ratios, assessed with BIS, have proven to be good markers of the nutritional and inflammatory status of HD patients. BIS may be a useful tool for regularly assessing the nutritional and hydration status in these patients and may allow nutritional advice to be improved and adjusted.

Proceso INFORNUT: validación de la fase de filtro-FILNUT--y comparación con otros métodos de detección precoz de desnutrición hospitalaria.

INTRODUCTION According to several series, hospital hyponutrition involves 30-50% of hospitalized patients. The high prevalence justifies the need for early detection from admission. There several classical screening tools that show important limitations in their systematic application in daily clinical practice. OBJECTIVES To analyze the relationship between hyponutrition, detected by our screening method, and mortality, hospital stay, or re-admissions. To analyze, as well, the relationship between hyponutrition and prescription of nutritional support. To compare different nutritional screening methods at admission on a random sample of hospitalized patients. Validation of the INFORNUT method for nutritional screening. MATERIAL AND METHODS In a previous phase from the study design, a retrospective analysis with data from the year 2003 was carried out in order to know the situation of hyponutrition in Virgen de la Victoria Hospital, at Malaga, gathering data from the MBDS (Minimal Basic Data Set), laboratory analysis of nutritional risk (FILNUT filter), and prescription of nutritional support. In the experimental phase, a cross-sectional cohort study was done with a random sample of 255 patients, on May of 2004. Anthropometrical study, Subjective Global Assessment (SGA), Mini-Nutritional Assessment (MNA), Nutritional Risk Screening (NRS), Gassull's method, CONUT and INFORNUT were done. The settings of the INFORNUT filter were: albumin < 3.5 g/dL, and/or total proteins <5 g/dL, and/or prealbumin <18 mg/dL, with or without total lymphocyte count < 1.600 cells/mm3 and/or total cholesterol <180 mg/dL. In order to compare the different methods, a gold standard is created based on the recommendations of the SENPE on anthropometrical and laboratory data. The statistical association analysis was done by the chi-squared test (a: 0.05) and agreement by the k index. RESULTS In the study performed in the previous phase, it is observed that the prevalence of hospital hyponutrition is 53.9%. One thousand six hundred and forty four patients received nutritional support, of which 66.9% suffered from hyponutrition. We also observed that hyponutrition is one of the factors favoring the increase in mortality (hyponourished patients 15.19% vs. non-hyponourished 2.58%), hospital stay (hyponourished patients 20.95 days vs. non-hyponourished 8.75 days), and re-admissions (hyponourished patients 14.30% vs. non-hyponourished 6%). The results from the experimental study are as follows: the prevalence of hyponutrition obtained by the gold standard was 61%, INFORNUT 60%. Agreement levels between INFORNUT, CONUT, and GASSULL are good or very good between them (k: 0.67 INFORNUT with CONUT, and k: 0.94 INFORNUT and GASSULL) and wit the gold standard (k: 0.83; k: 0.64 CONUT; k: 0.89 GASSULL). However, structured tests (SGA, MNA, NRS) show low agreement indexes with the gold standard and laboratory or mixed tests (Gassull), although they show a low to intermediate level of agreement when compared one to each other (k: 0.489 NRS with SGA). INFORNUT shows sensitivity of 92.3%, a positive predictive value of 94.1%, and specificity of 91.2%. After the filer phase, a preliminary report is sent, on which anthropometrical and intake data are added and a Nutritional Risk Report is done. CONCLUSIONS Hyponutrition prevalence in our study (60%) is similar to that found by other authors. Hyponutrition is associated to increased mortality, hospital stay, and re-admission rate. There are no tools that have proven to be effective to show early hyponutrition at the hospital setting without important applicability limitations. FILNUT, as the first phase of the filter process of INFORNUT represents a valid tool: it has sensitivity and specificity for nutritional screening at admission. The main advantages of the process would be early detection of patients with risk for hyponutrition, having a teaching and sensitization function to health care staff implicating them in nutritional assessment of their patients, and doing a hyponutrition diagnosis and nutritional support need in the discharge report that would be registered by the Clinical Documentation Department. Therefore, INFORNUT would be a universal screening method with a good cost-effectiveness ratio.

Celecoxib reduces symptoms in men with difficult chronic pelvic pain syndrome (Category IIIA)

We investigated the effectiveness of celecoxib in reducing symptoms in patients with difficult chronic pelvic pain syndrome (CPPS), NIH category IIIA. Sixty-four patients with category IIIA CPPS were randomized into two groups of 32 subjects each. One group was treated with celecoxib (200 mg daily) and the other with placebo. All patients underwent treatment for 6 weeks and were evaluated clinically before (baseline) and after 1, 2, 4, 6, and 8 weeks of treatment. The evaluation included the NIH Chronic Prostatitis Symptom Index (NIH-CPSI) and a subjective global assessment (SGA). Repeated measures analysis of variance was used to evaluate treatment and time effects and their interaction. A decrease (means ± SD) in total NIH-CPSI score from 23.91 ± 5.27 to 15.88 ± 2.51 in the celecoxib group and from 24.25 ± 5.09 to 19.50 ± 2.50 in the placebo group was observed during treatment (0 to 6 weeks). A statistically significant decrease was observed in pain subscore (P < 0.006), quality of life subscore (P < 0.032) and total NIH-CPSI score (P < 0.015) after 2, 4 and 6 weeks, but not in urinary subscore. In addition, 38% of the celecoxib and 13% of the placebo subjects had at least a moderate improvement in SGA. The trend was similar for the NIH-CPSI scores. However, the response to treatment in terms of total NIH-CPSI score or subscore was not significantly different from placebo after interruption of treatment for 2 weeks. Our results show that celecoxib provides significant symptomatic improvement limited to the duration of the therapy in patients with difficult category IIIA CPPS compared to placebo.

Clinical outcome of protein-energy malnourished patients in a Brazilian university hospital

Protein-energy malnutrition (PEM) is a treatable disease with high prevalence among hospitalized patients. It can cause significant increases in the duration of hospitalization and costs. PEM is especially important for health systems since malnourished patients present higher morbidity and mortality. The objective of the present study was to assess the evolution of nutritional status (NS) and the effect of malnutrition on clinical outcome of patients at a public university hospital of high complexity in Brazil. Patients hospitalized in internal medicine (n = 54), oncology (n = 43), and infectious diseases (n = 12) wards were included. NS was evaluated using subjective global assessment up to 48 h after admission, and thereafter at intervals of 4-6 days. On admission, patients (n = 109) were classified as well-nourished (n = 73), moderately malnourished or at risk of malnutrition (n = 28), and severely malnourished (n = 8). During hospitalization, malnutrition developed or worsened in 11 patients. Malnutrition was included in the clinical diagnosis of only 5/36 records (13.9% of the cases, P = 0.000). Nutritional therapy was administered to only 22/36 of the malnourished patients; however, unexpectedly, 6/73 well-nourished patients also received commercial enteral diets. Complications were diagnosed in 28/36 malnourished and 9/73 well-nourished patients (P = 0.000). Death occurred in 12/36 malnourished and 3/73 well-nourished patients (P = 0.001). A total of 24/36 malnourished patients were discharged regardless of NS. In summary, malnutrition remains a real problem, often unrecognized, unappreciated, and only sporadically treated, even though its effects can be detrimental to the clinical course and prognosis of patients. The amount of public and private funds unnecessarily dispersed because of hospital malnutrition is significant.

Malnourished patients on hemodialysis improve after receiving a nutritional intervention

INTRODUCTION: Malnutrition is multifactorial and may be modified by nutritional intervention. We aimed to assess the impact of an intervention on the nutritional status of malnourished hemodialysis patients and their acceptance of a non-industrialized nutritional supplement. METHODS: 18 patients were studied, they were selected from a previous nutritional assessment where nutritional risk was defined as: subjective global assessment > 15 plus one criterion for malnutrition. The following variables were assessed: anthropometric parameters, subjective global assessment, dietary intake, six-minute walking test, quality of life (SF-36), and biochemical tests. Patients were randomized to either Control or Intervention Groups. The Intervention Group received a dietetic supplement during dialysis containing 355 kcal, prepared from simple ingredients. After three months, subjects from the Control Group and other patients also considered at nutritional risk underwent the same intervention. The study groups were compared after three months, and all patients were analyzed before and after the intervention. RESULTS: Fifteen men and three women, aged 56.4 ± 15.6 years-old, nine in each group, were studied. The Intervention Group showed an improvement in the subjective global assessment (p = 0.04). There were differences in role physical and bodily pain domains of SF-36, with improvement in the Intervention Group and worsening in the Control Group (p = 0.034 and p = 0.021). Comparisons before and after intervention for all patients showed improvement in the subjective global assessment (16.18 ± 4.27 versus 14.37 ± 4.20, p = 0.04), and in the six-minute walking test (496.60 ± 132.59 versus 547.80 ± 132.48 m; p = 0.036). The nutritional supplement was well tolerated by all patients, and it did not cause side effects. CONCLUSIONS: The nutritional intervention improved the subjective global assessment and quality of life of hemodialysis patients at short-term. A global intervention by a dietitian produced specific and nonspecific positive effects in the whole group. Nutritional supplementation was feasible, palatable, and had low cost. Its clinical impact and effectiveness need to be further assessed in a larger group of patients at long-term.

Nutritional evaluation of stage 5 chronic kidney disease patients on dialysis

CONTEXTO E OBJETIVO: Portadores de insuficiência renal crônica em diálise apresentam alta prevalência de desnutrição proteico-energética. Não existe ainda um método uniforme para avaliar o estado nutricional desses pacientes. Recomenda-se a aplicação de um conjunto de métodos subjetivos e objetivos para se chegar aos diagnósticos nutricionais adequados. O objetivo deste estudo é traçar o perfil nutricional de pacientes submetidos a hemodiálise. TIPO DE ESTUDO E LOCAL: Estudo transversal descritivo realizado na Unidade de Tratamento Dialítico de Araraquara, São Paulo, Brasil, em 2008. MÉTODOS: 48 pacientes tiveram seus indicadores antropométricos e bioquímicos caracterizados, sendo também submetidos ao questionário Avaliação Global Subjetiva modificada (SGAm), verificando-se possíveis correlações entre esses indicadores. RESULTADOS: A frequência de desnutrição moderada e grave variou de 22% a 54%, de acordo com o parâmetro utilizado. Com relação à adequação do peso ideal, 29% da amostra estavam com porcentagem de adequação abaixo do percentil 75, classificados como portadores de desnutrição moderada e grave. As correlações mais significativas foram observadas entre índice de massa corporal (IMC) e adequações de prega triciptal (PCT), circunferência do braço (CB) e circunferência muscular do braço (CMB); e entre o SGAm e adequações de CB e CMB. CONCLUSÃO: A desnutrição apresentou grande variabilidade de frequência entre os pacientes de acordo com o critério escolhido para avaliação. O acompanhamento nutricional de rotina e a validação de métodos que avaliem a composição corporal desses pacientes são de extrema importância para diagnosticar precocemente a desnutrição e assim prevenir complicações e reduzir as taxas de morbimortalidade nesta população.

Avaliação dos indicadores nutricionais e da composição corporal em hepatopatas crônicos e a relação com a etiologia e gravidade da doença

Pós-graduação em Bases Gerais da Cirurgia - FMB