Parametric investigations of short length hydro-dynamically lubricated conical journal bearing

Due to the growing need for compact size fluid film bearings, efforts are being made to explore the performance of hydro-dynamically lubricated short length conical journal bearing. The combined radial and axial load carrying features of these bearings emerge as a better option to replace the two separate bearings (journal and thrust pad bearings) employed in turbo-machines and other applications. Thus, in this study, attempts have been made to investigate the performance of conical hydrodynamic journal bearing by using finite element analysis. The bearings have been investigated for semi-cone angle (γ = 10°), aspect ratio (λ = 0.5, 0.8, 1.0), journal speed (v = 2.6, 5.2 m/s) and load variations in terms of eccentricity ratio (ε) up to 0.6. Results have been presented in terms of radial and axial load carrying capacity, stiffness coefficients, damping coefficients and threshold speed. Results from the present study reveal that load carrying capacity is improved with higher aspect ratio; whereas threshold speed decreases with the increase of eccentricity ratio and aspect ratio

HIV-1 Enhancing Effect of Prostatic Acid Phosphatase Peptides Is Reduced in Human Seminal Plasma

We recently reported that HIV-1 infection can be inhibited by innate antimicrobial components of human seminal plasma (SP). Conversely, naturally occurring peptidic fragments from the SP-derived prostatic acid phosphatase (PAP) have been reported to form amyloid fibrils called “SEVI” and enhance HIV-1 infection in vitro. In order to understand the biological consequence of this proviral effect, we extended these studies in the presence of human SP. PAP-derived peptides were agitated to form SEVI and incubated in the presence or absence of SP. While PAP-derived peptides and SEVI alone were proviral, the presence of 1% SP ablated their proviral activity in several different anti-HIV-1 assays. The anti-HIV-1 activity of SP was concentration dependent and was reduced following filtration. Supraphysiological concentrations of PAP peptides and SEVI incubated with diluted SP were degraded within hours, with SP exhibiting proteolytic activity at dilutions as high as 1∶200. Sub-physiological concentrations of two prominent proteases of SP, prostate-specific antigen (PSA) and matriptase, could degrade physiological and supraphysiological concentrations of PAP peptides and SEVI. While human SP is a complex biological fluid, containing both antiviral and proviral factors, our results suggest that PAP peptides and SEVI may be subject to naturally occurring proteolytic components capable of reducing their proviral activity

U.S. Adolescents’ Diet Consumption Patterns Differ between Grocery and Convenience Stores: National Health and Nutrition Examination Survey 2011–2018

Among U.S. adolescents, foods/beverages that are store-bought (i.e., from grocery and convenience stores) are significant contributors of energy intake. However, it remains unclear (1) what foods/beverages are consumed by U.S. adolescents from grocery and convenience stores and (2) if there are differences in foods/beverages consumed by store type. Therefore, we analyzed 29,216 eating occasions from adolescents (12–19 years; n = 4065) in the National Health and Nutrition Examination Survey 2011–2018 to report food/beverage groups and nutrients consumed from grocery and convenience stores. Differences in food/beverage groups and nutrient densities by store type were calculated using multiple logistic and linear regressions. Adolescents were more likely to consume “Beverages” and “Snacks and Sweets” and less likely to consume “Grains”, “Protein”, “Milk and Dairy”, “Condiments and Sauces”, and “Fruits” from convenience compared to grocery stores (all p < 0.0025). Foods/beverages from convenience stores were higher in carbohydrates, total sugar, and added sugar and lower in protein, fat, saturated fat, sodium, and fiber than those from grocery stores (all p < 0.0025). In conclusion, while foods/beverages from convenience stores are more energy-dense and nutrient-poor, there is a critical need to increase the availability, accessibility, and affordability of healthier foods/beverages in both store types to encourage healthier dietary behaviors among U.S. adolescents

Spin fluctuations in Cr doped MnSi

Transport and calorimetric properties of Mn1-xCrxSi (x = 0.025) down to 2 K and magnetic fields up to 13 T are reported. Electrical resistivity in zero field as well as in magnetic fields, below a magnetic transition temperature, T-c = 23.6 K could be described using a T-2 term with large coefficient, invoking the role of spin fluctuations. Sommerfeld coefficient 'gamma' of specific heat is an enhanced one as compared to the pure MnSi. Negative magnetoresistance (35% at 13 T) with maximum at T-c and a decrease in coefficient of T-2 term in resistivity suggests the suppression of spin fluctuations in high magnetic fields. This is further supported by negative magneto-specific heat in the vicinity of T-c coupled with a decrement in the Sommerfeld coefficient 'gamma' of specific heat under a field of 10 T. Kadowaki-Woods ratio places the system close to other systems showing strong spin fluctuations. (C) 2017 Elsevier B.V. All rights reserved