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According to scientific studies dealing with the statistics of ICE (internal combustion engine) failures, most of them are registered in the ignition system (25%) and the power system (35%). The operable state of the ICE fuel system can be maintained by developing effective testing methods. For the purpose of theoretical research, a DBD-4 testing device was designed in the methodological part of the research. The use of the developed methodologies and instrumentation allowed carrying out experimental studies to diagnose the operability of the fuel supply system. Analyzing the obtained experimental data, it can be affirmed that: there is a stable relationship between the change in the ICE crankshaft speed and the change in the injection duration of the electromagnetic injector; the degree of wear of the electric fuel pump (EFP) is determined by the shift of the stable value of the crankshaft speed to the zone of low speed values at the same injection durations. The data obtained after testing the EFP allows planning a further algorithm of actions to maintain the operability of the fuel supply system.

Alcohol-associated hepatitis (AH) is a form of liver failure with high short-term mortality. Recent studies have shown that defective function of hepatocyte nuclear factor 4 alpha (HNF4a) and systemic inflammation are major disease drivers of AH. Plasma biomarkers of hepatocyte function could be useful for diagnostic and prognostic purposes. Herein, an integrative analysis of hepatic RNA sequencing and liquid chromatography-tandem mass spectrometry was performed to identify plasma protein signatures for patients with mild and severe AH. Alcohol-related liver disease cirrhosis, nonalcoholic fatty liver disease, and healthy subjects were used as comparator groups. Levels of identified proteins primarily involved in hepatocellular function were decreased in patients with AH, which included hepatokines, clotting factors, complement cascade components, and hepatocyte growth activators. A protein signature of AH disease severity was identified, including thrombin, hepatocyte growth factor α, clusterin, human serum factor H-related protein, and kallistatin, which exhibited large abundance shifts between severe and nonsevere AH. The combination of thrombin and hepatocyte growth factor α discriminated between severe and nonsevere AH with high sensitivity and specificity. These findings were correlated with the liver expression of genes encoding secreted proteins in a similar cohort, finding a highly consistent plasma protein signature reflecting HNF4A and HNF1A functions. This unbiased proteomic-transcriptome analysis identified plasma protein signatures and pathways associated with disease severity, reflecting HNF4A/1A activity useful for diagnostic assessment in AH.

HfxZr1-xO2 and lanthanum-doped HfxZr1-xO2:La thin films are candidates for applications in ferroelectric random-access memory. Here, we explore the atomic and electronic structure of Hf0.5Zr0.5O2 and Hf0.5Zr0.5O2:La thin films grown by atomic layer deposition. Using X-ray photoelectron spectroscopy, it was found that the oxides under study have an almost identical electronic structure and a bandgap of about 5.4 eV. The Hf0.5Zr0.5O2:La film was shown to consist of the mixture of Hf0.5Zr0.5O2 and La2O3 phases. The bombardment with argon ions of the studied films leads to oxygen vacancy generation in the near-surface layer. The oxygen vacancy concentrations in the bombarded films were evaluated from the comparison of experimental valence band photoelectron spectra with the theoretical ones calculated using the density functional theory.

A significant jump in the development of machine building technologies requires the adjustment of environmental indicators. The main sources of air pollution are vehicles with internal combustion engines. According to research data, the main share of toxic emissions is accounted for by the engine idle mode and constant load mode. Studies carried out to improve fuel efficiency of diesel engines which have been in operation for some time show the potential for increasing the efficiency by deactivating a portion of the cylinders. At the same time, the improvement of efficiency indicators varies within a wide range - from 4 to 30%. The larger the number of deactivated cylinders, the higher the fuel economy effect, but as the effective power increases, it is advisable to reduce their number. The potential for increasing efficiency by deactivating a portion of the cylinders is incorporated in all diesel engines in operation. The efficiency of cylinder deactivation is confirmed by experimental data obtained on various types of engines, including automobile, tractor, diesel locomotive, and ship engines. This method is known in engine building primarily as a means of increasing the efficiency of diesel engines at idle speed and small loads. It has been established that there is a decrease in the hourly fuel consumption to 33% of the rated effective power when engine cylinders are deactivated compared to operation without cylinder deactivation. A diesel engine was tested on a running-brake stand fitted with the necessary measuring and recording equipment and instruments, allowing for a maximum torque of 363 N·m at the crankshaft speed within 1200–3000 min−1. Our studies covered three engine operation options. It has been established experimentally that the specific indicator fuel consumption in the second mode, as compared to the first mode, decreases to 9% due to a decrease in the hourly fuel consumption at the speeds from 1600 min−1 to 2350 min−1. In the third mode, fuel economy at idle speed with a shutdown of the fuel supply and the drive of the gas distribution mechanism of the 2nd and 3rd cylinders was about 24% at the engine shaft speed in the range from 1200 min−1 to 2350 min−1. Upgrading the diesel engine using an electromagnetic fuel valve will pay itself off in about a year. A comparison of the experimental and theoretical data shows that their discrepancy in the whole range of the engine crankshaft speeds does not exceed 7%.

Important elements of the preoperative assessment that should be addressed for the older adult population include frailty, comorbidities, nutritional status, cognition, and medications. Frailty has emerged as a plausible predictor of adverse outcomes after surgery. It is present in older patients and is characterized by multisystem physiologic decline, increased vulnerability to stressors, and adverse clinical outcomes. Preoperative preparation may include a prehabilitation program, which aims to address nutritional insufficiencies, modify chronic polypharmacy, and enhance physical and respiratory conditions prior to hospital admission. Special considerations are taken for particularly high-risk patients, where the approach to prehabilitation can address specific, individual risk factors. Identifying patients who are nutritionally deficient allows practitioners to intervene preoperatively to optimize their nutritional status, and different strategies are available, such as immunonutrition. Previous studies have shown an association between increased frailty and the risk of postoperative complications, morbidity, hospital length of stay, and 30-day and long-term mortality following general surgical procedures. Evidence from numerous studies suggests a potential benefit of including a standard assessment of frailty as part of the preoperative workup of older adult patients. Studies addressing validated frailty assessments and the quantification of their predictive capabilities in various surgeries are warranted.

Natural gas is of the most interest out of a whole range of currently used motor fuels since it can reduce harmful emissions to the atmosphere. The impact large vehicle fleets have on the environment is, as a rule, higher than the impact of private motor vehicles due to large annual mileage. A single management center for such fleets can provide more reliable information on the operating conditions of vehicles, and replacement of diesel engines with gas ones in vehicle fleets of large cities will improve the environmental conditions of urbanized areas. The article analyzes potential consumers of compressed-gas trucks in cities. The migration of vehicles of utility companies to natural gas will reduce the volume of harmful emissions to the atmosphere and the noise level at garbage pickup in the morning. Studies on the safety of compressed natural gas (CNG) vehicles have confirmed its high level. Nevertheless, reliability matters remain relevant. The suggested method for prediction of possible failures and service planning, as well as prediction of operating conditions will take into account the prospects of enlargement of gas-engine vehicle fleets and the ways to reduce the environmental load.

We study modular differential equations for the basic weak Jacobi forms in one abelian variable with applications to the elliptic genus of Calabi--Yau varieties. We show that the elliptic genus of any $CY_3$ satisfies a differential equation of degree one with respect to the heat operator. For a $K3$ surface or any $CY_5$ the degree of the differential equation is $3$. We prove that for a general $CY_4$ its elliptic genus satisfies a modular differential equation of degree $5$. We give examples of differential equations of degree two with respect to the heat operator similar to the Kaneko--Zagier equation for modular forms in one variable. We find modular differential equations of Kaneko--Zagier type of degree $2$ or $3$ for the second, third and fourth powers of the Jacobi theta-series., 16 pages

This contribution presents U-Pb geochronological data for Ca-Fe-Ti garnets from compositionally diverse alkaline and carbonatitic intrusive rocks ranging from Neoarchean to Permian-Triassic (Cinder Lake and Eden Lake in Manitoba, Canada; Belaya Zima and Odikhincha in Siberia, Russia; Afrikanda in the Kola Peninsula, Russia) obtained using isotope-dilution thermal-ionization mass spectrometry (ID-TIMS) and their trace-element compositions measured by laser-ablation inductively-coupled-plasma mass spectrometry (LA-ICPMS). The studied garnets yield U-Pb concordant or subconcordant ages obtained with a precision of

Scandium oxide films with thickness d = 20–100 nm were deposited by atomic layer deposition (ALD) using tris(methylcyclopentadienyl) scandium (III) Sc(MeCp)3 and water vapors as precursors at reactor temperature range of 200–400 °C. The ALD-window was detected in the range of 230–370 °C. Growth per cycle remained constant and was 0.080–0.084 nm/cycle in this range. O/Sc ratio was found to be 1.49 which is close to stoichiometric Sc2O3. The films were polycrystalline. The grains were more apparent for the films grown at higher temperatures. The grain size increased with thickness. Cubic Sc2O3 phase was determined by FTIR, Raman spectroscopy and X-rays diffraction. In general, different crystallographic directions are more preferential for different process conditions. Films were textured and their growth occurred mainly in the (400) direction. The refractive index dispersions of deposited films were well described by the Cauchy model. Optical properties depended weakly on process parameters (temperature or thickness). As it was detected for the films with close thickness the refractive index slightly increased with deposition temperature increase. The Nasyrov-Gritsenko (N-G) multiphonon trap ionization model well describes the charge transport. The trap parameters were determined to be: concentration N = 1.5 × 1019 cm−3, thermal energy Wt = 0.83 eV, and optical energy Wopt = 1.66 eV.

We demonstrate how the configuration and magnitude of a magnetic field, applied during magnetron sputtering of a NiFe/IrMn bilayer, influence the magnetic properties of the structure, such as hysteresis loop shape, coercivity, and exchange bias. Furthermore, we illustrate that it is possible to create a stepwise hysteresis loop in the sample's region with the highest field gradient. The found features can be used for future sensor applications., Comment: 8 pages, 7 figures