Numerical Simulation on Convection and Thermal Radiation of Casson Fluid in an Enclosure with Entropy Generation.

The goal of the current numerical simulation is to explore the impact of aspect ratio, thermal radiation, and entropy generation on buoyant induced convection in a rectangular box filled with Casson fluid. The vertical boundaries of the box are maintained with different constant thermal distribution. Thermal insulation is executed on horizontal boundaries. The solution is obtained by a finite volume-based iterative method. The results are explored over a range of radiation parameter, Casson fluid parameter, aspect ratio, and Grashof number. The impact of entropy generation is also examined in detail. Thermal stratification occurs for greater values of Casson liquid parameters in the presence of radiation. The kinetic energy grows on rising the values of Casson liquid and radiation parameters. The thermal energy transport declines on growing the values of radiation parameter and it enhances on rising the Casson fluid parameter.

Cor triatiratum dexter: a rare cause of isolated right atrial enlargement.

Cor triatriatum sinistrum (division of the left atrium) is a recognized clinical and surgical entity. Division of the right atrium, also known as cor triatriatum dexter, is an extremely rare congenital abnormality in which persistence of the right valve of the embryonic systemic sinus venosus divides the right atrium into two chambers. Typically, the right atrial partition is due to exaggerated fetal eustachian and thebesian valves, which together form an incomplete septum across the lower part of the atrium. This septum may range from a reticulum to a substantial sheet of tissue. Cor triatriatum dexter can be diagnosed at any age, especially if it is incidentally discovered. Usually, this anomaly is recorded at necropsy. This report describes the case of a divided right atrium evaluated for nonspecific symptoms and unexplained cardiomegaly with right atrial enlargement.

Effect of Al2O3 (x = 0, 1, 2, and 3 vol.%) in CrFeCuMnNi-x High-Entropy Alloy Matrix Composites on Their Microstructure and Mechanical and Wear Performance.

This work aims to study the influence of Al2O3 in CrFeCuMnNi high-entropy alloy matrix composites (HEMCs) on their microstructure, phase changes, and mechanical and wear performances. CrFeCuMnNi-Al2O3 HEMCs were synthesized via mechanical alloying (MA) followed by hot compaction (550 °C at 550 MPa), medium frequency sintering (1200 °C), and hot forging (1000 °C at 50 MPa). The XRD results demonstrate the formation of both FCC and BCC phases in the synthesized powders, which were transformed into major stable FCC and minor ordered B2-BCC phases, as confirmed by HRSEM. The microstructural variation of HRSEM-EBSD, in terms of the coloured grain map (inverse pole figures), grain size distribution, and misorientation angle, was analysed and reported. The grain size of the matrix decreased with the increase in Al2O3 particles owing to the higher structural refinement by MA and zener pinning of the incorporated Al2O3 particles. The hot-forged CrFeCuMnNi-3 vol.% Al2O3 sample exhibited an ultimate compressive strength of 1.058 GPa, which was 21% higher than that of the unreinforced HEA matrix. Both the mechanical and wear performance of the bulk samples increased with an increase in Al2O3 content due to solid solution formation, high configurational mixing entropy, structural refinement, and the effective dispersion of the incorporated Al2O3 particles. The wear rate and coefficient of friction values decreased with the increase in Al2O3 content, indicating an improvement in wear resistance owing to the lower domination of abrasive and adhesive mechanisms, as evidenced by the SEM worn surface morphology.

Evaluation of the biocompatibility, antibacterial and anticancer effects of a novel nano-structured Fe-Mn-based biodegradable alloys in-vitro study.

Scientific backgrounds: Development of nanostructured biodegradable alloys has generated a great deal of interest in the recent years as they offer promising bioactive materials for reconstruction of bony defects following traumatic fractures or surgical excision of tumors. Objectives: The aim of the current study was to investigate the biocompatibility of Iron-Manganese -based alloys (Fe-Mn) with addition of copper (Cu), Tungsten (W) and cobalt (Co) to obtain 3 different alloys namely, Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co on normal oral epithelial cell line,and their possible anticancer effect on MG-63: osteosarcoma cell line. Materials and methods: The sulforhodamine B (SRB) assay was used to assess cell viability percentage of both cell lines after exposure to discs of the proposed experimental alloys. Moreover, the antibacterial effect of such alloys against Escherichia coli (E. coli) was tested using disc diffusion susceptibility (Kirby-Bauer method) and colony suspension method. Results: The cell viability percentage of oral epithelial cell line showed a significant increase in all the experimental groups in comparison to the control group. The highest percentage was observed in Fe-Mn-Co group, followed by Fe-Mn-W then Fe-Mn-Cu, at 24 and 72-h intervals, respectively. While the cell viability percentage of osteosarcoma cell line showed significant increase in all the experimental groups at 24-h intervals, it showed a significant drop in all the study groups at 72-h intervals. The lowest percentage was observed in Fe-Mn-Cu group, followed by Fe-Mn-W then Fe-Mn-Co. Moreover, all the examined study groups didn't show any inhibition zones against E. coli reference culture. Conclusions: The novel nanostructured biodegradable Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co metal alloys exhibit good biocompatibility on oral epithelial cell lines with the enhancement of cell proliferation in a time-dependent manner that favors bone regeneration. On the other hand, all the alloys manifested possible anticancer activity against MG-63: osteosarcoma cell line. Furthermore, our study sheds the light on the importance of Co, W and Cu as promising alloying elements. However, the antibacterial activity of the examined alloys is still questionable. Clinical relevance: The novel nanostructured biodegradable Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co metal alloys offer promising bioactive materials for reconstruction of bony defects following traumatic fractures or surgical excision of tumors, In addition, they could be excellent alternatives for undegradable or non-resorbable alloys that are commonly used. Moreover, they could be used as beneficial 3D printing materials to obtain patient-specific medical implants that favor bone regeneration in addition to manufacturing of plates and screws suitable for fracture fixation.

Tropical endomyocardial fibrosis in India: a vanishing disease!

Tropical endomyocardial fibrosis in India was a common medical problem in the coastal districts of south India, especially the Kerala State. The clinical and autopsy studies have shown left and right ventricular apical fibrosis, with varying degree of atrioventricular valve regurgitation. Left ventricular endomyocardial fibrosis presents with severe pulmonary hypertension and right ventricular endomyocardial fibrosis presents very high systemic venous pressure and congestive cardiac failure. Surgical management improved the natural history of the disease to some extent. Various infectious and toxic factors were postulated regarding its aetiology. During the last few years, incidence of the disease has decreased considerably. The only explanation identified is the significant improvement in the living standards of the people with the corresponding decline in the childhood malnutrition, infections, worm infestation and associated eosinophilia.

Usefulness of Doppler derived end diastolic flow gradient across the patent ductus arteriosus in selecting coils for ductal occlusion.

Transcatheter closure of patent ductus arteriosus (PDA) with coils is accepted as an alternative to surgical ligation. We evaluated whether flow gradient across PDA, obtained by Doppler echocardiography, can aid in selecting coils for percutaneous ductal occlusion. 79 consecutive patients with PDA, who underwent successful percutaneous coil occlusion were retrospectively reviewed. Patients with other structural heart disease and pulmonary hypertension with right-to-left shunt were excluded. Echocardiogram and cardiac catheterization were done in all patients. Gianturco (Occluding Spring Emboli; Cook, Bloomington, IN) non-detachable coils of 0.038 and 0.052-inch core sizes were used for ductal occlusion. Trough diastolic gradient was correlated with the size and the number of coils used. Mean age was 8.6 years (range 1.3 to 27 years); 24 males and 55 females; PDA diameter ranged from 1.3 to 4.5 mm. Number of coils used varied from 1 to 4. Echocardiography measured PDA size was 2.5 ± 0.6 mm and significantly differed from angiographically measured size 2.9 ± 0.6 mm (P = 0.05). End diastolic gradient below 38 mmHg predicted use of multiple coils or coils with larger surface area. End diastolic gradient correlated inversely with total surface area of the coils, which indirectly predicted size and number of coils. Thus, the prediction of the size and the number of coils for PDA occlusion can be assisted by the trough diastolic gradients of PDA.

Once weekly azithromycin in secondary prevention of rheumatic fever.

Rheumatic fever and rheumatic heart disease (RHD) are still important problems in developing countries. Secondary prophylaxis which is the most cost-effective method in preventing recurrences of rheumatic fever is fraught with problems of drug compliance. The utility of 500 mg once weekly azithromycin (AZT), an orally effective long-acting antibiotic was evaluated against oral penicillin (phenoxy methyl penicillin 250 mg twice daily) in this study. Forty-eight consecutive patients (44% males, mean age 29.4 years) with established RHD were randomised into two groups-26 patients received AZT and 22 received oral penicillin. Patients were evaluated at randomisation, at 1 month, 3 months, and 6 months, clinically, serologically and by throat swab culture. End points were absence of streptococcal colonisation, infection or fever at the end of 6 months. During the study, 4 patients (15.4%) in the AZT group developed sore throat and fever, had positive throat culture and positive serology indicating streptococcal infection. None satisfied the criteria for rheumatic fever reactivation. None in the oral penicillin group developed streptococcal infection. In conclusion, weekly 500 mg of AZT is not effective in the prevention of streptococcal throat infection compared to oral penicillin therapy in adult patients with established RHD.

Left atrial myxoma-influence of tumour size on electrocardiographic findings.

OBJECTIVE: The data of 51 patients (33 females) who underwent excision of left atrial (LA) myxoma were retrospectively reviewed for correlation of tumour size and electrocardiographic (ECG) findings. METHODS AND RESULTS: Mean age was 39.1 ± 15 years (range 9-53 years). The LA enlargement (LAE) on ECG was defined by standard criteria. The LAE in ECG in these patients did not correlate with echocardiographic LA dimensions or with the degree of left ventricular (LV) inflow obstruction. But it was found that the presence of LAE in ECG predicted maximum tumour dimension of >5 cm and correlated with the degree of mitral regurgitation (MR). The LAE in ECG disappeared following surgery in 87.5% of patients. CONCLUSION: The LA enlargement on ECG in a patient with LA myxoma signifies larger tumour size or the presence of significant MR but is not necessarily associated with an increased LA size or LV inflow obstruction.

Addressing healthcare needs of people living below the poverty line: a rapid assessment of the Andhra Pradesh Health Insurance Scheme.

BACKGROUND: Families living below the poverty line in countries which do not have universal healthcare coverage are drawn into indebtedness and bankruptcy. The state of Andhra Pradesh in India established the Rajiv Aarogyasri Community Health Insurance Scheme (RACHIS) in 2007 with the aim of breaking this cycle by improving the access of below the poverty line (BPL) families to secondary and tertiary healthcare. It covered a wide range of surgical and medical treatments for serious illnesses requiring specialist healthcare resources not always available at district-level government hospitals. The impact of this scheme was evaluated by a rapid assessment, commissioned by the government of Andhra Pradesh. The aim of the assessment was to explore the contribution of the scheme to the reduction of catastrophic health expenditure among the poor and to recommend ways by which delivery of the scheme could be improved. We report the findings of this assessment. METHODS: Two types of data were used for the assessment. Patient data pertaining to 89 699 treatment requests approved by the scheme during its first 18 months were examined. Second, surveys of scheme beneficiaries and providers were undertaken in 6 randomly selected districts of Andhra Pradesh. RESULTS: This novel scheme was beginning to reach the BPL households in the state and providing access to free secondary and tertiary healthcare to seriously ill poor people. CONCLUSION: An integrated model encompassing primary, secondary and tertiary care would be of greater benefit to families below the poverty line and more cost-effective for the government. There is considerable potential for the government to build on this successful start and to strengthen equity of access and the quality of care provided by the scheme.

Long term outcomes after bare metal stent implantation.

Long term outcome data after BMS implant is not available from the Indian subcontinent. This is a prospective observational study which aims to study long term outcomes after BMS implant at a tertiary care centre. 100 consecutive patients underwent BMS implant and were followed up for 20 years. LAD was the most common vessel involved and different types of BMS were implanted. All-cause mortality was noted in 21% (n = 21) whereas cardiac mortality was seen in 16% (n = 16). Cumulative revascularisation free survival at 20 years was 71%. The study showed that long term outcomes after BMS implant were fare and acceptable.

The cardio-protective diet.

Globalization has made calorie rich, cheap, convenient marketed foods the main menu for the common man. Indians are particularly susceptible to the adverse outcomes of this dietary change because of ethnic, epigenetic reasons and sarcopenic adiposity (less muscle more fat for the same body weight). Children have smaller body frame making them more susceptible to adverse effects of hyperglycaemia leading to stress on beta cells and their damage. This has resulted in escalation of lifestyle diseases by three-fold, that too at our younger age group at lower body mass indices. Preventive measures are necessary in early life to protect the beta cells, to achieve a metabolically healthy society. This will help in sustaining optimal beta cell function throughout a person's life. Modification in dietary habits by educating the society, proper food labelling and legal regulation, restricting calorie, sugar, saturated fat, trans-fat and salt intake has proved its benefits in the developed world. Changes in the quality of food is as important as restricting calorie intake. This includes facilitation of increased consumption of dietary fiber, complex carbohydrates, nuts, fruits and vegetables. Restrictions are needed to reduce trans-fats, saturated fats and cooking habits such as deep frying which oxidizes cholesterol and lipids. Foods with long shelf-life shorten the life line because of their salt, sugar or trans-fat content. Individual meals need to be targeted in the general dietary guidelines, to minimize the post-prandial metabolic insult. In general, we need healthy start to early life particularly the first twenty years of life so that the habits cultured during childhood are sustained for the rest of productive years.

Efficacy and safety of combination of extended release niacin and atorvastatin in patients with low levels of high density lipoprotein cholesterol.

OBJECTIVE: We investigated the safety and efficacy of combination therapy of extended release (ER) niacin and atorvastatin in patients with low HDL-C and compared the results with atorvastatin monotherapy. METHODS: This open label study recruited consecutive men and women who had coronary artery disease with HDL-C levels <35 mg/dL. These patients were already on atorvastatin therapy targeted to lower low density lipoprotein cholesterol (LDL-C), for a minimum period of 6 months. Group 1, n = 104 (mean age 52.7 years) received ER niacin in addition to atorvastatin and group 2 (n = 106) continued on atorvastatin (mean age 52.3 years). ER niacin dose was built up to a maximum of 1.5 g and atorvastatin dose titrated according to LDL levels in both the groups. The lipoprotein levels at baseline were similar (p = NS). RESULTS: At 9 +/- 1.8 months of follow-up, the mean dose of ER niacin was 1.3 g and atorvastatin 13.2 mg in group 1. In comparison, group 2 patients had mean atorvastatin dose of 15.9 mg. Patients in group 1 had significant elevation in HDL-C cholesterol (39.5 +/- 5.5 vs 35.7 +/- 4.5 mg/dL), reduction in total cholesterol (156.4 +/- 31 vs 164.5 +/- 39.3 mg/dL) and also LDL-C (88.9 +/- 28.3 vs 99.8 +/- 35.4 mg/dL) compared to group 2 (all p < 0.05). The magnitude of reduction in triglyceride levels was not significant between the groups (140.1 +/- 40.4 vs 145.2 +/- 46.5 mg/dL) (p = NS). No major adverse events or clinical myopathy occurred in either groups. Four patients (4%) discontinued ER niacin (2 due to gastro-intestinal symptoms and 2 due to worsening of diabetes). Flushing occurred in 3% patients, but none felt it to be troublesome. CONCLUSION: Adding ER niacin to atorvastatin exhibited beneficial effects on lipid profile with significant elevation of HDL-C cholesterol and further lowering of LDL-C compared to monotherapy. This treatment offered better targeted therapy and was well tolerated with proper monitoring in Indian patients.

Changing household dietary behaviours through community-based networks: A pragmatic cluster randomized controlled trial in rural Kerala, India.

TRIAL DESIGN: With the rise in prevalence of non-communicable diseases in India and Kerala in particular, efforts to develop lifestyle interventions have increased. However, contextualised interventions are limited. We developed and implemented contextualised behavioural intervention strategies focusing on household dietary behaviours in selected rural areas in Kerala and conducted a community-based pragmatic cluster randomized controlled trial to assess its effectiveness to increase the intake of fruits and vegetables at individual level, and the procurement of fruits and vegetables at the household level and reduce the consumption of salt, sugar and oil at the household level. METHODS: Six out of 22 administrative units in the northern part of Thiruvananthapuram district of Kerala state were selected as geographic boundaries and randomized to either intervention or control arms. Stratified sampling was carried out and 30 clusters comprising 6-11 households were selected in each arm. A cluster was defined as a neighbourhood group functioning in rural areas under a state-sponsored community-based network (Kudumbasree). We screened 1237 households and recruited 479 (intervention: 240; control: 239) households and individuals (male or female aged 25-45 years) across the 60 clusters. 471 households and individuals completed the intervention and end-line survey and one was excluded due to pregnancy. Interventions were delivered for a period of one-year at household level at 0, 6, and 12 months, including counselling sessions, telephonic reminders, home visits and general awareness sessions through the respective neighbourhood groups in the intervention arm. Households in the control arm received general dietary information leaflets. Data from 478 households (239 in each arm) were included in the intention-to-treat analysis, with the household as the unit of analysis. RESULTS: There was significant, modest increase in fruit intake from baseline in the intervention arm (12.5%); but no significant impact of the intervention on vegetable intake over the control arm. There was a significant increase in vegetable procurement in the intervention arm compared to the control arm with the actual effect size showing an overall increase by19%; 34% of all households in the intervention arm had increased their procurement by at least 20%, compared to 17% in the control arm. Monthly household consumption of salt, sugar and oil was greatly reduced in the intervention arm compared to the control arm with the actual effect sizes showing an overall reduction by 45%, 40% and 48% respectively. CONCLUSIONS: The intervention enabled significant reduction in salt, sugar and oil consumption and improvement in fruit and vegetable procurement at the household level in the intervention arm. However, there was a disconnect between the demonstrated increase in FV procurement and the lack of increase in FV intake. We need to explore fruit and vegetable intake behaviour further to identify strategies or components that would have made a difference. We can take forward the lessons learned from this study to improve our understanding of human dietary behaviour and how that can be changed to improve health within this context.

Acute phase reactants predict mitral regurgitation following mitral valvuloplasty.

This report evaluated whether acute phase reactants can predict the development of mitral regurgitation following percutaneous mitral valvotomy. 58 patients who developed significant mitral regurgitation following valvotomy were retrospectively compared with 58 age, sex and procedure technique matched control patients, who had valvotomy without mitral regurgitation. ESR and total leucocyte count were significantly higher in the group who developed mitral regurgitation, than in the control group. Higher ESR and total leucocyte count may be indicative of ongoing low grade sub-clinical inflammatory process, which makes the valve tissue friable which can give way during balloon stretch and lead onto mitral regurgitation.

Prevalence-correlates-awareness-treatment and control of hypertension in kumarakom, kerala: baseline results of a community-based intervention program.

BACKGROUND, Hypertension is one of the major causes of cardiovascular morbidity and mortality. However, awareness, treatment, and control of hypertension remain major challenges worldwide. In this article, we present the baseline prevalence of hypertension from an ongoing intervention program for its control in a community-based sample in Kerala, Southern India. METHODS, We measured blood pressure, body weight, and height of 4955 individuals above the age of 30 yers (men;2159:mean-age: 50 years) and collected information on alcohol use, tobacco use, and other demographic variables using a pre-tested structured questionnaire. RESULTS, The overall prevalence of hypertension (JNC-VII) was 36.7% ( 95% CI:35.5-38.0; men: 36.0% and women 37.2% ) in multipile logistic regression analysis, a body mass index of >/=25 kg/m(2) was associated with a 1.65-fold (95% CI:1.37-1.98) prevalence of hypertension compared to a body mass index <25kg/m(2). Individuals with diabetes mellitus had 2.10 higher odds of hypertension prevalence (95% CI: 1.62-2.73) compared to people wihtout diabetes mellitus. Participants with increased waist circumference (90 cm in men, 85 cm in women) were 1.84 times more likely to be hypertensive compared to those with normal waist circumference (95% CI: 1.55-2.19). Among hypertensives, 24% were aware of the condition, 20% were on treatment, and 6.4% achieved effective blood pressure control. CONCLUSION, A higher body mass index, increased waist circumference, and self-reported diabetes mellitus were the important correlates of hypertension in our community-based sample. Our data emphasize the importance of educational interventions and appropriate lifestyle modifications that target increased body mass index and waist circumference to reduce the community burden of hypertension.