A Particle Dispersion Model For Analysis Of Two-Dimensional Mixing In Open Channels

Pollutant mixing in natural rivers is analyzed by using the two-dimensional depth-averaged advection-dispersion model (2D ADE) for rapid completion of the vertical mixing. The dispersion term in the 2D ADE follows Taylor’s assumption (Taylor, 1954; Fischer et al., 1979) which can be applied in the Taylor period. However, most open channel flow has long initial period which makes the skewed concentration distribution due to the unbalance between the shear flow advection and the vertical mixing (Chatwin, 1970). Therefore, the non-Fickian dispersion model is necessary to compensate the limitations of the 2D ADE model. In this research, the two-dimensional particle dispersion model (2D PDM) was developed to analyze the pollutant mixing both in the initial and the Taylor period without determination of the dispersion coefficient. In the 2D PDM, pollutant particles were introduced to visualize physical mixing process according to the complicate flow variation in open channels. The 2D PDM is based on the shear flow dispersion theory and adopted the operator split method which divides the shear advection stage and the turbulent diffusion stage. In the shear advection stage, particles were separated by the vertical velocity deviations in the longitudinal and transverse directions. The separated particles according to the shear flow were mixed across the vertical in the turbulent diffusion stage. After the particle mixing, the particle distribution in each time step was converted to the concentration field for various analysis. The 2D PDM was applied to the straight channel and the meandering channel for analysis of the conservative pollutant mixing. In the straight channel, concentration curves from the 2D PDM showed skewed distribution in the initial period and then turned into the Gaussian distribution in the Taylor period. And, the concentration distributions in the meandering channel showed good agreement with the tracer test results

Reconstructive challenge of dermatofibrosarcoma protuberans in the female breast

Dermatofibrosarcoma protuberans is an uncommon locally aggressive malignant neoplasm that most frequently appears in the trunk, followed by the extremities, head, and neck. But occurrence in the breast is extremely rare. We present a case of a 28-year-old woman, who had a history of trauma 5 years previously and excision 1 year before presentation at our clinic. We performed wide excision, together with microscopic and immunohistochemical analysis. No postoperative oncologic treatment was used and she remains disease-free 1 year after the surgery without any tumor recurrence. Here, we report a case of dermatofibrosarcoma protuberans in the female breast and present a detailed discussion of the diagnosis and treatment with reference to available literatures

Relationship between Physical Disability and Depression by Gender:A Panel Regression Model

Background Depression in persons with physical disabilities may be more common than in the general population. The purpose of this study was to examine the relationship between physical disability and depression by gender among adults, using a large, nationally representative sample. Methods This study used data from the Korean Longitudinal Study of Aging, Wave one through four, and ran a series of random effect panel regression models to test the relationship between physical disability status and depression by gender. We tested the moderating effect of gender on the relationship between disability status and depression level by examining the significance of the cross-product term between disability status and gender. Results After controlling for self-rated health, marital status, employment status, education, and age, subjects who were female or diagnosed as having any disability presented higher levels of depression scores. Further, the difference in terms of their depression level measured by Center for Epidemiologic Studies Short Depression Scale (CES-D 10) scores between those who were diagnosed as having any disability and those who were not was greater for females than for their male counterparts. Conclusion This study reaffirmed that disability is the risk factor of depression, using longitudinal data. In addition, female gender is the effect modifier rather than the risk factor. The effect of gender in the non-disability group, mostly composed of older persons, is limited. On the contrary, the female disability group showed more depressive symptoms than the male disability group. The gender difference in the disability group and the role of culture on these differences need further research

Anti-diabetic effect of Cyclo-His-Pro (CHP)-enriched yeast hydrolysate in streptozotocin-induced diabetic mice

The present study was designed to investigate the hypoglycemic effects of the daily oral dose of 0.50 to 0.75 g/kg of yeast hydrolysate (YH) containing high Cyclo-His-Pro (51.0 mg CHP/g YH) on normal and streptozotocin (STZ)-induced diabetic rats for 14 days. In STZ-induced diabetic rats, after administrations of the YH for 14 days, the body weight gain was significantly increased in dose dependent manner, and the plasma glucose levels were decreased approximately (60%) as compared to the STZ induced diabetic control group. Glucose level showed significant differences between the diabetic control (DC) and the YH administered groups in oral glucose tolerance test (OGTT) (P<0.05). Results of the OGTT showed a significant decrease in the area under curve (AUC) value of YH supplemented groups as compared to the DC group. The present data suggests that the CHP-enriched YH has potential anti-diabetic effect, which can help in the cure and management of diabetes.Keywords: Yeast hydrolysate, Cyclo-His-Pro (CHP), diabetes, streptozotocin.African Journal of Biotechnology Vol. 12(35), pp. 5473-547

Comparison of out-of-hospital cardiac arrests during the COVID-19 pandemic with those before the pandemic: an updated systematic review and meta-analysis

The coronavirus disease of 2019 (COVID-19) pandemic, directly and indirectly, affected the emergency medical care system and resulted in worse out-of-hospital cardiac arrest (OHCA) outcomes and epidemiological features compared with those before the pandemic. This review compares the regional and temporal features of OHCA prognosis and epidemiological characteristics. Various databases were searched to compare the OHCA outcomes and epidemiological characteristics during the COVID-19 pandemic with before the pandemic. During the COVID-19 pandemic, survival and favorable neurological outcome rates were significantly lower than before. Survival to hospitalization, return of spontaneous circulation, endotracheal intubation, and use of an automated external defibrillator (AED) decreased significantly, whereas the use of a supraglottic airway device, the incidence of cardiac arrest at home, and response time of emergency medical service (EMS) increased significantly. Bystander CPR, unwitnessed cardiac arrest, EMS transfer time, use of mechanical CPR, and in-hospital target temperature management did not differ significantly. A subgroup analysis of the studies that included only the first wave with those that included the subsequent waves revealed the overall outcomes in which the epidemiological features of OHCA exhibited similar patterns. No significant regional differences between the OHCA survival rates in Asia before and during the pandemic were observed, although other variables varied by region. The COVID-19 pandemic altered the epidemiologic characteristics, survival rates, and neurological prognosis of OHCA patients.Review registration: PROSPERO (CRD42022339435)

Anti-malarial activity of 6-(8'Z-pentadecenyl)-salicylic acid from Viola websteri in mice

<p>Abstract</p> <p>Background</p> <p>Petroleum ether extracts of <it>Viola websteri </it>Hemsl (Violaceae) were reported to have anti-plasmodial activity against <it>Plasmodium falciparum in vitro</it>, with this activity being largely attributable to 6-(8'Z-pentadecenyl)-salicylic acid (6-SA).</p> <p>Methods</p> <p>The schizontocidal activity of 6-SA on early <it>Plasmodium berghei </it>infections was evaluated in a four-day test. The possible 'repository' activity of 6-SA was assessed using the method described by Peters. The median lethal dose (LD₅₀) of 6-SA, when given intraperitoneally, was also determined using uninfected ICR mice and the method of Lorke.</p> <p>Results</p> <p>In the present study, 6-SA was found to have anti-malarial activity <it>in vivo</it>, when tested against <it>P. berghei </it>in mice. 6-SA at 5, 10 and 25 mg/kg·day exhibited a significant blood schizontocidal activity in four-day early infections, repository evaluations and established infections with a significant mean survival time comparable to that of the standard drug, chloroquine (5 mg/kg·day).</p> <p>Conclusion</p> <p>6-SA possesses a moderate anti-malarial activity that could be exploited for malaria therapy.</p

Clinical outcomes of chemoradiotherapy for locally recurrent rectal cancer

<p>Abstract</p> <p>Background</p> <p>To assess the clinical outcome of chemoradiotherapy with or without surgery for locally recurrent rectal cancer (LRRC) and to find useful and significant prognostic factors for a clinical situation.</p> <p>Methods</p> <p>Between January 2001 and February 2009, 67 LRRC patients, who entered into concurrent chemoradiotherapy with or without surgery, were reviewed retrospectively. Of the 67 patients, 45 were treated with chemoradiotherapy plus surgery, and the remaining 22 were treated with chemoradiotherapy alone. The mean radiation doses (biologically equivalent dose in 2-Gy fractions) were 54.6 Gy and 66.5 Gy for the chemoradiotherapy with and without surgery groups, respectively.</p> <p>Results</p> <p>The median survival duration of all patients was 59 months. Five-year overall (OS), relapse-free (RFS), locoregional relapse-free (LRFS), and distant metastasis-free survival (DMFS) were 48.9%, 31.6%, 66.4%, and 40.6%, respectively. A multivariate analysis demonstrated that the presence of symptoms was an independent prognostic factor influencing OS, RFS, LRFS, and DMFS. No statistically significant difference was found in OS (p = 0.181), RFS (p = 0.113), LRFS (p = 0.379), or DMFS (p = 0.335) when comparing clinical outcomes between the chemoradiotherapy with and without surgery groups.</p> <p>Conclusions</p> <p>Chemoradiotherapy with or without surgery could be a potential option for an LRRC cure, and the symptoms related to LRRC were a significant prognostic factor predicting poor clinical outcome. The chemoradiotherapy scheme for LRRC patients should be adjusted to the possibility of resectability and risk of local failure to focus on local control.</p