8 research outputs found
Conformal Efficiency Factors of Friction Pairs in Construction Machinery
Formulae for the efficiency factor of moving friction pairs of construction equipment are investigated in terms of their mutual adaptation (conformism) during friction and wear. As a basis, the average coefficients of sliding friction and dimensions of the reference line curves, the half-sums of their products of the worn surfaces microrelief for mating parts are taken. Coefficients of sliding friction and dimensions of reference lines were determined from the partial values of microwear and micromaterial of the normalized system of relative reference lines and convergences. Calculated values of conformal efficiency factors were compared with efficiency factors obtained from the tested dependence, as well as from the wedge operator in the dry friction mode. The research was carried out on the example of model hinges of hydraulic excavator attachments
Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19
Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe
Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies
There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity
Conformal Efficiency Factors of Friction Pairs in Construction Machinery
Formulae for the efficiency factor of moving friction pairs of construction equipment are investigated in terms of their mutual adaptation (conformism) during friction and wear. As a basis, the average coefficients of sliding friction and dimensions of the reference line curves, the half-sums of their products of the worn surfaces microrelief for mating parts are taken. Coefficients of sliding friction and dimensions of reference lines were determined from the partial values of microwear and micromaterial of the normalized system of relative reference lines and convergences. Calculated values of conformal efficiency factors were compared with efficiency factors obtained from the tested dependence, as well as from the wedge operator in the dry friction mode. The research was carried out on the example of model hinges of hydraulic excavator attachments
Memoirs of a captivity in Japan, during the years 1811, 1812, and 1813 : with observations on the country and the people /
Translation of Zapiski o prikli͡uchenii͡akh ... v pli͡enu u i͡apont͡sev.Vols. 2, p. [227]-356 has separate t.p.: Account of voyages to the coasts of Japan ; and of the negotiations with the Japanese, for the release of captain Golownin and his companions. By P. Rikord." ; Vol. 3 has caption title: Recollections of Japan, and p. [251]-302 has separate t.p.: "Account of Messrs. Chwostoff & Dawidoff", by Vice-Admiral Schischkoff.Mode of access: Internet
3D Printed Microfluidic Cell for SAXS Time-Resolved Measurements of the Structure of Protein Crystallization Solutions
A multichannel microfluidic cell (MFC) obtained using 3D printing for studying the structure of complex solutions by small-angle X-ray scattering (SAXS) is described. MFC was tested at the BioMUR beamline of the Kurchatov synchrotron. A comparative analysis of SAXS signal from the standard capillary and from the developed MFC was carried out, with MFC showing significant advantages. The dynamics of SAXS scattering curves for lysozyme solutions with NaCl precipitant were studied when the protein and precipitant concentrations changed. The obtained time series of data are well consistent with the known data for the lysozyme solution