3,089 research outputs found
Improvement of Adhesion of the Wheels of the Railway Carriage to the Rails by Means of Supply of the Scale and Magnetite Particles to the Contact Zone
The article proposes a method to improve adhesion of the wheels to the rails of the railway carriage
by means of supply of abrasive loose materials as an alternative to quartz sand to the zone of their contact:
metal scale (Fe₃O₄ ) being the waste of rolling and forging, as well as the iron oxide—magnetite (FeO·Fe₂O₃) of the natural origin. The comparative assessment of efficiency of use of scale and magnetite was carried out
in relation to quartz sand traditionally used for railway transport. The adhesion coefficient and wear intensity
are used as comparison criteria
Trans-, cis-, and dihydro-resveratrol: a comparative study
BACKGROUND: Recent studies showed that moderate consumption of red or white wines increased the chances of breast cancer, while similar consumption of red wines, rich in trans-resveratrol (trans-R), decreased the rate of prostate cancer. This prompted us to explore the role of various forms of R in cancer proliferation. RESULTS: Trans-R was found to be the most potent antiproliferative agent. Cis-R demonstrated somewhat less potency compared to trans-R. Unlike cis-R and trans-R, dihydro-R exhibits moderate proliferative effect on androgen-independent prostate cancer cell lines PC-3 and DU-145 at picomolar concentrations. At higher concentrations, dihydro-R caused proliferation inhibition, similar to cis-R and trans-R. The proliferative effect of dihydro-R at low concentrations can be reversed by trans-R which acts as a partial antagonist in the presence of dihydro-R. Mixtures of dihydro-R and trans-R demonstrated complex non-monotonic cross-modulation activity patterns. CONCLUSIONS: Dihydro-R exhibits proliferative effects in androgen-independent prostate cancer cells at picomolar and nanomolar concentrations. While the exact mechanism of these effects requires further evaluation, our preliminary results point to hormone receptor modulation activity. We also observed strong cross modulation between trans-R and dihydro-R at sub-picomolar concentrations. The role of dihydro-R in cancer proliferation related to moderate consumption of red wine remains an open question because dihydro-R has a very complex activity pattern in the presence of trans-R
Cytotoxic Activity of Peripheral Blood Mononuclear Leukocytes, Activated by Interleukin-2/β-Cyclodextrin Nanocomposition against Androgen Receptor-Negative Prostate Cancers
Nanocomposition comprised of interleukin-2 in suboptimal noneffective concentration and β-cyclodextrin was studied in vitro. This preparation as well as interleukin-2 in optimal concentration was shown to increase natural killer activity to K-562 cells and cytotoxicity of activated peripheral blood mononuclear cells (PBMCs) against PC-3 and DU 145 cells. At the same time β-cyclodextrin or interleukin-2 in equimolar concentrations did not influence the spontaneous killer activity of PBMC. This combination of cyclodextrin + interleukin-2 led to the decrease of interleukin-2 effective concentration by an order. This phenomenon could be explained by cyclodextrins ability to promote the formation of nanoparticles with drugs, which results in enhancing their water solubility and bioavailability. Besides, interleukine-2/β-cyclodextrin nanocomposition as opposed to interleukin-2 alone led to increasing the number of not only lymphocytes, but also macrophages contained in activated PBMC population. Application of low concentration of interleukin-2 allowing for good clinical efficiency may significantly mitigate the side effects of the drug and enable to develop adoption of immunotherapy for patients with androgen-resistant prostate cancer
Friction Unit of a Disc Brake Based on a Combination of Friction Materials
The design of the disc brake friction unit is proposed, the basis for the creation of which is a combination of friction materials with different properties. As a criterion for the structural formation of a friction unit of a disc brake, it is proposed to use the initial equality of linear wear rates for all brake linings made of
friction materials with different properties. It is shown that the use of a friction unit based on combined friction materials makes it possible to achieve new disc brake characteristics, compared to its traditional design.
It is concluded that the proposed solution is promising
Discovery and SAR exploration of N-aryl-N-(3-aryl-1,2,4-oxadiazol-5-yl)amines as potential therapeutic agents for prostate cancer
A new chemical series of antiproliferative compounds was identified via high-throughput screening on DU-145 human prostate carcinoma cell line (hit compound potency - 5.7 μM). Exploration of the two peripheral diversity vectors of the hit molecule in a hit-targeted library and testing of the resulting compounds led to SAR generalizations and identification of the 'best' pharmacophoric moieties. The latter were merged in a single compound that exhibited a 200-fold better potency than the original hit compound. Specific cancer cell cytotoxicity was confirmed for the most potent compounds
Эффективность основного внесения удобрений и подкормок томата при капельном орошении на обыкновенных чернозёмах Ростовской области
Relevance. In modern vegetable growing in the southern and central regions of Russia, new scientific developments are widely used, including the use of new varieties and hybrids, a drip irrigation system, fertigation with soluble fertilizers with microelements. All these agricultural practices make it possible to increase the yield of vegetable crops by several times, as well as to significantly increase the efficiency of applied fertilizers. The purpose of our work was to establish the effectiveness of the use of calculated doses of mineral fertilizers for tomato with the main application and top dressing under drip irrigation.Methodology. Research in 2019-2021 on ordinary heavy loamy chernozem of the experimental field of the Birutchecutskaya Vegetable Experimental Station – branch of FSBSI Federal Scientific Vegetable Center (Rostov Region, Novocherkassk) with a new variety of tomato Krasny banker.Results. It was revealed that without fertilization, the yield of tomatoes was at the level of 32-35 t/ha; the use of the recommended dose of N120P120K120 in the main application increased the yield to 64- 72 t/ha; the use of the estimated dose of mineral fertilizers (for a yield of 100 t/ha) increased the yield of tomatoes to 95 t/ha. The use of three-fold root feeding of plants with drip irrigation increased the yield by 21%, and with foliar feeding – by 2-8%. As a root top dressing for drip irrigation, a solution of microcrystalline water-soluble fertilizer "Master" with a different ratio of nutrients was used, and for foliar top dressing, an organomineral nanofertilizer with growth-stimulating activity "Arksoil KKR" was used. In general, a set of agrochemical practices made it possible to increase the tomato yield under drip irrigation from 33.7 to 102.8 t/ha, more than 3 times, without reducing the dry matter content in fruits and without nitrate contamination of products. Актуальность. В современном овощеводстве южных и центральных регионов России широко используются новые научные разработки, включающие в себя использование новых сортов и гибридов, систему капельного орошения, фертигацию растворимыми удобрениями с микроэлементами. Все эти агроприёмы позволяют в несколько раз увеличить урожайность овощных культур, а также очень существенно повысить эффективность вносимых удобрений.Целью нашей работы было установить эффективность применения расчётных доз минеральных удобрений под томат при основном внесении и подкормках в условиях капельного орошения. Исследования проводили в 2019-2021 годах на обыкновенном тяжелосуглинистом чернозёме опытного участка Бирючекутской овощной селекционной опытной станции (БОСОС) ФНЦО (Ростовская обл., г. Новочеркасск) с новым сортом томата Красный банкир.Результаты. Выявлено, что без внесения удобрений урожайность томатов была на уровне 32 35 т/га; применение в основное внесение рекомендуемой дозы N120P120K120 увеличивало урожайность до 64-72 т/га; использование расчётной дозы минеральных удобрений (на урожайность 100 т/га) повышало урожайность томатов до 89-99 т/га. Применение трёхкратной корневой подкормки растений при капельном орошении увеличивало урожайность на 21%, а при листовой подкормке – на 2 8%. В качестве корневых подкормок при капельном поливе использовался раствор микрокристаллического водорастворимого удобрения «Мастер» различного соотношения питательных элементов, а при листовых подкормках органоминерального наноудобрения с ростостимулирующей активностью «Арксойл ККР». В целом, комплекс агрохимических приёмов позволил увеличить урожайность томата при капельном орошении с 33,7 до 102,8 т/га, более чем в 3 раза, без снижения содержания сухого вещества в плодах и отсутствии нитратного загрязнения продукции.
Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV
The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8 TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
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