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Boundary layer separation is a major cause of concern in the wind turbine and aerospace industries as it adversely affects the performance of aircraft wings and wind turbine blades. The immediate result of flow separation over an aerofoil causes decrease in lift and an increase in drag within the stall range, both of which have a negative impact on the overall performance of aerofoils in the wind turbines. To overcome this problem, vortex generators (VGs) are used for increasing lift force and thus increasing the rotational speed of the blade. They act like small protrusions on wing surfaces which helps in energizing the boundary layers thereby delaying the separation and providing a wide range of attached flow over aerofoil surface. The present research illustrates the comparative analysis on the various shapes of VGs such as rectangular, triangular and gothic by varying the angle of attacks (AoA) from 0-15 °. The analysis is performed on NACA0012 aerofoil, which is developed using SOLIDWORKS and analysed on ANSYS 2020 R2 software. The values of lift (Cl) and drag (Cd) coefficients with and without VGs are determined using ANSYS fluent and the contours for velocity and pressure are further mapped using CFD Post. The stall angle is evaluated for each of the VG shapes representing the maximum lift that an aerofoil can achieve. Pressure coefficient plots are studied in order to investigate the amount of pressure difference created and its influence AoA at the leading edge of the aerofoil. An overall comparison is made to determine the best VG shape that delivers maximum lift to the aerofoil. The optimum configuration found for VG is gothic shape which illustrates the maximum lift coefficient value, which is highest amongst all the three shapes. [ABSTRACT FROM AUTHOR]

An investigation has been carried out to investigate the effect of nozzle geometry on hot horizontal surface rewetting during water jet impingement cooling. The test surface of 800 ± 10°C initial surface temperature is cooled by water jet of 22 ± 1°C temperature. The water flow is varied to maintain the jet Reynolds number in a range of 5,000 to 24,000. The rewetting phenomena with sharp-edged and tube-type nozzles are compared on the basis of rewetting temperature, wetting delay, rewetting velocity, and maximum surface heat flux. The rewetting performance with tube-type nozzle is better than the sharp-edged nozzle particularly for the downstream spatial locations; however, maximum surface heat flux at the stagnation region is higher with the sharp-edged nozzle. [ABSTRACT FROM PUBLISHER]

B/L symmetrical sensorineural hearing loss has long been associated with diabetes Mellitus. Microangiopathy associated with thickening of the basement membrane of small vessels has been implicated as a major source. This study was done to observe the predominant site of lesion whether cochlear or retrocochlear in patients of diabetic sensorineural hearing loss. This was a random study. Forty two patients with diabetic B/L symmetrical sensorineural hearing loss were selected in a tertiary referral centre. All the patients selected were of diabetic B/L symmetrical sensorineural hearing loss. The study was designed to show the predominant site of lesion whether cochlear or retrocochlear in patients of diabetes with or without noise exposure. The parameter for inferring blood sugar control was level of glycosylated haemoglobin (Hb1AC). The incidence of the classical symptoms of diabetes mellitus namely polyurea, polydypsia and polyphagia were seen in (40.8%) of patients. The present study was designed to show that even early diabetic patients without symptoms of hearing loss had mild bilaterally symmetrical purely sensorineural hearing loss (32.65%) signifying the diabetic hypoacusis is present significantly even in early aural symptomless diabetics. On follow up it was revealed that the hearing loss of these patients was irreversible. The predominant site of lesion was found to be cochlear by performing Chi Square test P < .05 and so this is applicable to the general population of Uttar Pradesh. [ABSTRACT FROM AUTHOR]

Apparent mass method (Venkataraman and Croft, Nucl Instrum Methods Phys Res A 505:527, ), initially standardized for the assay of Pu (Agarwal et al., J Nucl Mater 651:386, ) has been used to get Pu amount in empty stainless steel boxes generally used for storing and transferring plutonium oxide powders. The results have been compared with the neutron coincidence counting results and have been found to match well. The advantage of the method is that it can be used for any sample with nonstandard geometry and with uncertain source distribution. [ABSTRACT FROM AUTHOR]

This Paper reports a late uncontrolled diabetic presenting to an otolaryngologist with sudden severe sensorineural hearing loss of immediate origin with vertigo and tinnitus as the symptoms. Appropriate investigative and treatment measure resulted in deterioration of hearing in the right ear and mild improvement of hearing in the left ear, with no recovery of imbalance. [ABSTRACT FROM AUTHOR]

Cumulative yields of 27 fission products have been determined in 229Th(n,f) by recoil catcher technique followed by gamma-ray spectrometry. Absolute fission yields were arrived at from the fission rate measured by track etch counting method. Mass yields were obtained from the cumulative yields using the charge distribution parameters reported in the literature. The values agree well with the reported values obtained both by physical and radiochemical methods. The resulting asymmetric mass distribution shows strong fluctuation in the yields in the light and heavy wings with a periodicity of five mass units. [ABSTRACT FROM AUTHOR]

Electronic switching in amorphous chalcogenide semiconductors has been observed and studied for nearly forty years. Technological exploitation of this phenomenon has most recently emerged in DVD's where GST, a compound of germanium, antimony, and tellurium, is used to store information. We explain how GST behaves as a switch and how X-ray absorption fine structure can be used to unlock the specifics of the switching process. The tool that leads to this deeper understanding is the bond constraint theory. We explain how this theory leads to an explanation of switching and of the behavior and properties of amorphous materials in general. Finally, the prospects for developing GST-related materials into non-volatile memory media that could be the basis for glass computers are discussed. [ABSTRACT FROM AUTHOR]

Chromosomal fragile sites are distributed all over the human genome. Aphidicolin mediated expression frequency of common fragile sites and other chromosomal changes were evaluated in prometa-phase/ metaphase chromosomes obtained from peripheral blood lymphocytes of colorectal cancer patients. The present study reveals first time high incidence i.e. 6 % of aphidicolin induced chromosome breaks / gaps designated as "common fragile sites" in cell population of clinically diagnosed patients of colorectal cancer patients in Nepalese population. These chromosomal changes including structural and numerical were compare to clinically healthy normal individual of same sex / age groups, act as controls for statistical analysis. The frequency of chromosomal aberration in cancer patients were significantly higher (p<0.001) when compare to normal individuals. The increased genetics instability probably either due to nutritional factor i.e. lack of folic acid component in diet--an essential component required for DNA synthesis or unknown environmental factor for such genetic disorder. The present study indicates aphidicolin high frequency of induced chromosome aberrations and "common fragile sites" because of late replication of DNA in mitosis in colorectal cancer patients suggesting these sites could be used as suitable marker for determining genetic predisposition in cancer patients. [ABSTRACT FROM AUTHOR]

The article describes the case of a 23-year-old man presented with a history of growing left scrotal swelling of two months duration. Case highlights include fine needle aspiration cytology, accurate diagnosis of scrotal masses to prevent therapeutic mismanagement, and cytological features for the diagnosis of a schwannoma.

Background Elderly patients with COVID-19 disease are at increased risk for adverse outcomes. Current data regarding disease characteristics and outcomes in this population are limited. Aim To delineate the adverse factors associated with outcomes of COVID-19 patients ≥75 years of age. Design Retrospective cohort study. Methods Patients were classified into mild/moderate, severe/very severe and critical disease (intubated) based on oxygen requirements. The primary outcome was in-hospital mortality. Results A total of 355 patients aged ≥75 years hospitalized with COVID-19 between 19 March and 25 April 2020 were included.Mean age was 84.3 years. One-third of the patients developed critical disease. Mean length of stay was 7.10 days. Vasopressors were required in 27%, with the highest frequency in the critical disease group (74.1%). Overall mortality was 57.2%, with a significant difference between severity groups (mild/moderate disease: 17.4%, severe/very severe disease: 71.3%, critical disease: 94.9%, P  < 0.001).Increased age, dementia, and severe/very severe and critical disease groups were independently associated with increased odds for mortality while diarrhea was associated with decreased odds for mortality (OR: 0.12, 95% CI: 0.02–0.60, P  < 0.05). None of the cardiovascular comorbidities were significantly associated with mortality. Conclusion Age and dementia are associated with increased odds for mortality in patients ≥75 years of age hospitalized with COVID-19. Those who require intubation have the greatest odds for mortality. Diarrhea as a presenting symptom was associated with lower odds for mortality. [ABSTRACT FROM AUTHOR]

Here, we assessed and compared the anticancer efficacy and associated mechanisms of silymarin and silibinin in human prostate cancer (PCA) PC3 cells; silymarin is comprised of silibinin and its other stereoisomers, including isosilybin A, isosilybin B, silydianin, silychristin and isosilychristin. Silymarin and silibinin (50–100 μg/ml) inhibited cell proliferation, induced cell death, and caused G1 and G2–M cell cycle arrest in a dose/time-dependent manner. Molecular studies showed that G1 arrest was associated with a decrease in cyclin D1, cyclin D3, cyclin E, cyclin-dependent kinase (CDK)4, CDK6 and CDK2 protein levels, and CDK2 and CDK4 kinase activity, together with an increase in CDK inhibitors (CDKIs) Kip1/p27 and Cip1/p21. Further, both agents caused cytoplasmic sequestration of cyclin D1 and CDK2, contributing to G1 arrest. The G2–M arrest by silibinin and silymarin was associated with decreased levels of cyclin B1, cyclin A, pCdc2 (Tyr15), Cdc2, and an inhibition of Cdc2 kinase activity. Both agents also decreased the levels of Cdc25B and cell division cycle 25C (Cdc25C) phosphatases with an increased phosphorylation of Cdc25C at Ser216 and its translocation from nucleus to the cytoplasm, which was accompanied by an increased binding with 14-3-3β. Both agents also increased checkpoint kinase (Chk)2 phosphorylation at Thr68 and Ser19 sites, which is known to phosphorylate Cdc25C at Ser216 site. Chk2-specific small interfering RNA largely attenuated the silymarin and silibinin-induced G2–M arrest. An increase in the phosphorylation of histone 2AX and ataxia telangiectasia mutated was also observed. These findings indicate that silymarin and silibinin modulate G1 phase cyclins–CDKs–CDKIs for G1 arrest, and the Chk2–Cdc25C–Cdc2/cyclin B1 pathway for G2–M arrest, together with an altered subcellular localization of critical cell cycle regulators. Overall, we observed comparable effects for both silymarin and silibinin at equal concentrations by weight, suggesting that silibinin could be a major cell cycle-inhibitory component in silymarin. However, other silibinin stereoisomers present in silymarin also contribute to its efficacy, and could be of interest for future investigation.Oncogene (2006) 25, 1053–1069. doi:10.1038/sj.onc.1209146; published online 3 October 2005 [ABSTRACT FROM AUTHOR]

Presents a study that examined whether silibinin is effective in inhibiting constitutive NF-κB activation in human prostate cancer (PCA) cells. Background on prostate cancer; Functions of the NF-κB family of transcription factors; Components of NF-κB; Conventional therapeutic measures of PCA; Comparison between silibinin and silymarin.

Background COVID-19 is an ongoing threat to society. Patients who develop the most severe forms of the disease have high mortality. The interleukin-6 inhibitor tocilizumab has the potential to improve outcomes in these patients by preventing the development of cytokine release storm. Aims To evaluate the outcomes of patients with severe COVID-19 disease treated with the interleukin-6 inhibitor tocilizumab. Methods We conducted a retrospective, case–control, single-center study in patients with severe to critical COVID-19 disease treated with tocilizumab. Disease severity was defined based on the amount of oxygen supplementation required. The primary endpoint was the overall mortality. Secondary endpoints were mortality in non-intubated patients and mortality in intubated patients. Results A total of 193 patients were included in the study. Ninety-six patients received tocilizumab, while 97 served as the control group. The mean age was 60 years. Patients over 65 years represented 43% of the population. More patients in the tocilizumab group reported fever, cough and shortness of breath (83%, 80% and 96% vs. 73%, 69% and 71%, respectively). There was a non-statistically significant lower mortality in the treatment group (52% vs. 62.1%, P  = 0.09). When excluding intubated patients, there was statistically significant lower mortality in patients treated with tocilizumab (6% vs. 27%, P  = 0.024). Bacteremia was more common in the control group (24% vs. 13%, P  = 0.43), while fungemia was similar for both (3% vs. 4%, P  = 0.72). Conclusion Our study showed a non-statistically significant lower mortality in patients with severe to critical COVID-19 disease who received tocilizumab. When intubated patients were excluded, the use of tocilizumab was associated with lower mortality. [ABSTRACT FROM AUTHOR]

The article offers information on the association of gene polymorphism with insulin resistance in a north Indian population. Topics discussed include genetic association of ENPP1/PC-1 K121Q polymorphism with obesity, homeostasis model assessment, and statistical analysis of alleles. Also present a table depicting clinical characteristics of study participants.

Objectives: The worldwide increasing prevalence of obesity is considered as a major health problem. Peroxisome proliferator-activated receptor gamma ( PPAR-γ) controls adipocyte differentiation and regulates a number of genes associated with energy homeostasis. In this study, we investigated the association of PPAR-γ gene Pro12Ala (rs1801282) and C1431T (rs3856806) polymorphisms with morbid obesity and related phenotypes, in north Indian population. Methods: A total of 6,42 subjects, 309, obese and 333 nonobese individuals were included in this case-control study. Insulin, adiponectin, glucose, and lipid levels were estimated using standard protocols. All subjects were genotyped by PCR restriction fragment length polymorphism (PCR-RFLP) method. Results: The ProAla+AlaAla genotypes of PPAR-γ Pro12Ala were significantly associated with higher risk of obesity while C1431T polymorphism did not show any significant association. None of the haplotypes showed association with morbid obesity. However, a strong association of variant genotypes was observed with higher levels of insulin, HOMA-IR, and lower serum adiponectin concentrations. Conclusion: PPAR-γ gene polymorphisms influence obesity and obesity phenotype in a complex manner, probably involving insulin resistance in north Indian population. Am. J. Hum. Biol., 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background: Obesity is a very common disorder directly linked with various diseases such as type-2 diabetes, hypertension and atherosclerosis. Variants in the FTO gene have been associated with Body Mass Index in Western European and North American populations. Aim: This study analysed the association between the FTO gene variant rs17817449 (G>T) and obesity and obesity-related phenotypes in a north Indian population. Subjects and methods: A total of 642 subjects, 309 obese and 333 non-obese individuals, were included in this case-control study. Genotyping of FTO gene (rs17817449) polymorphism for all subjects was performed by the PCR-RFLP method. Results: Significant associations were found for FTO rs17817449 SNP with obesity and obesity-related phenotypes. The strongest associations were observed between the rs17817449 and fasting blood glucose, insulin, homeostasis model of assessment-insulin resistance (HOMA-IR) and fat mass under a recessive model. Conclusions: This study replicated the genetic association of SNP of FTO (rs17817449) with obesity in a north Indian population and, to the authors' knowledge; this is the first such association study in a north Indian population. This study also established that SNP in intron 1 of FTO (rs17817449) are strongly associated with several measures of adiposity and are also associated with plasma insulin, insulin resistance, percentage body fat and fat mass. [ABSTRACT FROM AUTHOR]

A new method is proposed for determination of voltage and current sensitivities at different buses and branches of a radial power distribution network. First-order sensitivity expressions for bus voltage and branch current with respect to bus power load have been developed. These sensitivities expressions are then used to evaluate sensitivity constants at different buses and for various branches with respect to load variation at various buses. The method has been applied to a 33 KV, 41-bus practical distribution system. The results are compared with the conventional Jacobian method and almost negligible error has been observed. The evaluated voltage and current sensitivities for the 41-bus system are then used to determine the optimised limits of the existing network for forecast load to demonstrate the application of derived sensitivities. The method proposed here greatly reduces the computational effort compared to other existing methods. [ABSTRACT FROM AUTHOR]