Fecal Viral Concentration and Diarrhea in Norovirus Gastroenteritis

Fecal viral concentrations of 40 patients infected with norovirus genogroup GII.4 correlated with diarrhea duration and frequency of vomiting. Higher viral concentration and older age were independently associated with prolonged diarrhea (>4 days). These findings provide information on the pathogenesis and transmission of norovirus infections

Human Metapneumovirus-associated Atypical Pneumonia and SARS

Acute pneumonia developed in a previously healthy man during the outbreak of severe acute respiratory syndrome (SARS) in southern China in March 2003. Antibiotic treatment was ineffective, and he died 8 days after illness onset. Human metapneumovirus was isolated from lung tissue. No other pathogen was found. Other etiologic agents should thus be sought in apparent SARS cases when coronavirus infection cannot be confirmed

Cluster of SARS among Medical Students Exposed to Single Patient, Hong Kong

We studied transmission patterns of severe acute respiratory syndrome (SARS) among medical students exposed exclusively to the first SARS patient in the Prince of Wales Hospital in Hong Kong, before his illness was recognized. We conducted a retrospective cohort study of 66 medical students who visited the index patient’s ward, including 16 students with SARS and 50 healthy students. The risk of contracting SARS was sevenfold greater among students who definitely visited the index case’s cubicle than in those who did not (10/27 [41%] versus 1/20 [5%], relative risk [RR] 7.4; 95% confidence interval [CI] 1.0 to 53.3). Illness rates increased directly with proximity of exposure to the index case. However, four of eight students who were in the same cubicle, but were not within 1 m of the index case-patient, contracted SARS. Proximity to the index case-patient was associated with transmission, which is consistent with droplet spread. Transmission through fomites or small aerosols cannot be ruled out

Effects of die shapes and additives on the physical and mechanical properties, and cellular structure of biodegradable cushioning extruded foams

Efforts are focused on the effects of operating parameters, i.e., die shapes (DS), PVA ratio (PR), and additives (AT), on the physical and mechanical properties of corn-PVA extrudates in this study. The cellular structure of biodegradable extruded foams are studied and the extrudates are evaluated as cushioning materials. The process variables are the operating conditions, DS (O, infinity, Delta, and 0), PR (40, 50, 60%), and AT (8%) (sodium bicarbonate (NaHCO3), calcium carbonate (CaCO3), calcium hydroxide (Ca(OH)(2))). The experimental setup is a 4 x 3 x 3 factorial design. Samples of each treatment are collected and the physical and mechanical properties are measured and analyzed using the PROC ANOVA and PROC CORR of the SAS 6.0 software package. Moreover, the cellular structures of the extrudates are observed by using a scanning electron microscope. The experimental results indicate that: (a) the change of DS has a significant effect on the longitudinal expansion, bulk density, and compressibility of the extrudates; (b) the change of PR has a significant effect on the longitudinal expansion, bulk density, and compressibility of the extrudates; (c) the change of AT has a significant effect on the longitudinal expansion, bulk density, and compressibility of the extrudates; (d) the most uniform cell is obtained with the O-shaped die, as compared with other die shapes. A moderate cell wall is obtained with the O-shaped die. The largest cell sizes are found in PVA 60% with CaCO3. However, the smallest cell sizes are found in PVA 60% with NaHCO3. Changing the types of additives from NaHCO3 to CaCO3, and CaCO3 to Ca(OH)(2) increases the cell size and cell wall thickness

Physical, mechanical, biodegradable properties and energy absorption behavior of corn grit-polyvinyl alcohol cushioning extrudates

The focus of the study was on the effects of PVA ratio (PR), screw speed (SS) and die temperature (DT) on the physical, mechanical, biodegradable properties and energy absorption behavior of corn grit/PVA cushioning extrudates. The experimental results indicated that PR had a significant effect on the radial expansion ratio, bulk density, compressibility. spring index and biodegradable properties. SS had a significant effect on the radial expansion ratio, compressibility, spring index, biodegradable properties and the radial expansion ratio. DT had a most significant effect on the compressibility and spring index of the extrudates. Corn grit blended with 5% of PVA had the minimum total energy absorption (TEA) and energy absorption of each cycle (EAEC). All treatments of the extrudates had the maximum energy absorption at the crosshead speed 400 mm/min. The resultant extrudates were suitable for packaging applications especially cushioning materials. (c) 2004 Elsevier Ltd. All rights reserved

Study on the optimum feed compositions of biodegradable cellular foams blend with talc powder (talc)

Response surface methodology (RSM) is used to analyze the effect of polyvinyl alcohol (PVA) and talc powder (talc) on the objective (radial expansion ratio, bulk density, compressibility, and spring index) attributes of a biodegradable cushioning extrudate. A rotatable central composite design (CCD) is used to develop models for the objective responses. The experiments are run at 125 degrees C with a feed rate of 27.8 L/h, a screw speed of 215 rpm, and a die diameter of 3.92 mm. Responses are most affected by changes in PVA levels and to a lesser extent by talc levels. Individual contour plots of the different responses are overlaid, and regions meeting the optimum radial expansion ratio of 3.14, the bulk density of 0.106 g/cm(3), the compressibility of 56.12 N, and the spring index of 0.892 are identified at the PVA level of 32% and the talc level of 4%, respectively

Composition Optimization of Poly(vinyl alcohol)-/Cornstarch-Blended Biodegradable Composite Using Response Surface Methodology

Response surface methodology Was Used to analyze the effect of amylase level (X(1)) and glycerol level (X(2)) on the objective [water solubility index (WSI), water absorption index (WAI), and Max. loading] attributes of a poly(vinyl alcohol)-/cornstarch-blended composite. A rotable central-composite design (CCD) was used to develop models for the objective responses. The experiments were run at die temperature 100 degrees C with a feed rate of 25 g/min and a screw speed of 35 rpm. Responses were most affected by changes in the amylase level (X(1)) and to a lesser extent by glycerol level (X(2)). Individual contour plots of the different responses were overlaid, and regions meeting the optimum WSI of 3.03 (%), WAT of 5.08 (g gel/g dry wt), and Max. loading of 29.36 (N) were identified at the amylase level of 2.8 (mL) and the glycerol level of 92.2 (mL), respectively. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 258-264, 200

The study of optimum operating conditions of extruded snack food with tomato powder

Tomatoes are an integral part of diets worldwide. Many population studies have established a link between dietary intake of tomato, a major source of a carotenoid antioxidant, lycopene, and reduced risk of chronic diseases. Response surface methodology was used to analyze the effect of screw speed (X-1), moisture content (X-2) and tomato powder content (X-3) on the objective attributes (radial expansion ratio [Y-1], bulk density [Y-2], degree of gelatinization [DG], water absorption index [WAI] and hardness [Y-5]) of all extruded snack food with tomato powder. A Box-Behnken design was used to develop models for the objective responses. The experiments were performed at 100C with the following: feed rate, 19.2 kg/h; X-1, 250 rpm; and die diameter 3.98 mm. Individual contour plots of the different responses were overlaid. Regions meeting 3.22 optimum Y-1, 0.13-g/cm Y-2, 81.25% DG, 5.12-g gel/g dry weight WAI and 35.43-N Y-5 were identified at 12.5 and 25% X-2 and X-3, respectively

Cerebral microbleeds and white matter hyperintensities are associated with cognitive decline in an asian memory clinic study

Background: Cerebral Small Vessel Disease (SVD); lacunes, Cerebral Microbleeds (CMBs), and White Matter Hyperintensities (WMH) have a vital role in cognitive impairment and dementia. SVD in lobar location is related to cerebral amyloid angiopathy, whereas SVD in a deep location with hypertensive arteriopathy. It remains unclear how different locations of SVD affect long-term cognitive decline. The present study aimed to analyse the association between different locations and severity of SVD with global and domain-specific cognitive decline over the follow-up interval of 3 years. Methods: We studied 428 participants who had performed MRI scans at baseline and at least 3 neuropsychological assessments. Locations of lacunes and CMBs were categorized into strictly lobar, strictly deep and mixed-location, WMH volume into anterior and posterior. The National Institute of Neurological Disorders and Stroke-Canadian Stroke Network Harmonization Neuropsychological Battery was used to assess cognitive function. To analyse the association between baseline location and severity of SVD with cognitive decline, linear regression models with generalized estimated equations were constructed to calculate the mean difference, 95% confidence interval and two-way interaction factor between time and SVD. Results: Increased numbers of baseline CMBs were associated with a decline in global cognition as well as a decline in executive function and memory domains. Location-specific analysis showed similar results with strictly lobar CMBs. There was no association with strictly deep and mixed-location CMBs with cognitive decline. Baseline WMH volume was associated with a decline in global cognition, executive function and memory. Similar results were obtained with anterior and posterior WMH volumes. Lacunes and their locations were not associated with cognitive decline. Conclusion: Strictly lobar CMBs, as well as WMH volume in anterior and posterior regions, were associated with cognitive decline. Future research focuses are warranted to evaluate interventions that may prevent cognitive decline related to SVD