Increasing Fatigue LIfe of 09Mn2Si Steel by means of High-Temperature Multistep Helical Rolling

The effect of high temperature helical rolling (HR) on structure and fatigue life of 09Mn2Si pipe steel has been studied. With the use of transmission electron microscopy there was revealed that rolling gives rise to refinement of ferrite grains and cracking (fracturing) of cementite plates within the pearlite phase. The effect manifests itself to the greatest extent in the surface layer where due to the rolling the level of plastic deformation was the highest. Data of microhardness measurements confirms the gradient pattern of strain hardening over the cross section during the HR occurs while the most intensive microhardness increasing take place at the depth of up to 3 mm. According to the mechanical testing results the helical rolling of 09Mn2Si steel gives rise to increasing the level of deforming stress at the yield plateau as well as the proportionality limit with a general decrease in the relative elongation. At the same time, despite the strain hardening resulting from the helical rolling the mechanisms of plastic deformation which manifest themselves in the form of parabolic hardening with a smooth decrease in the flow stress level after neck formation are preserved in the steel. During the cyclic tension the number of cycles prior to failure increases from 2.5 to 3.8 times that depends on the location of specimens' cutting from the rolled rod. The highest improvement in fatigue fracture resistance is registered for specimens cut out from the core of the rolled rods

Increasing Fatigue LIfe of 09Mn2Si Steel by means of High-Temperature Multistep Helical Rolling

The effect of high temperature helical rolling (HR) on structure and fatigue life of 09Mn2Si pipe steel has been studied. With the use of transmission electron microscopy there was revealed that rolling gives rise to refinement of ferrite grains and cracking (fracturing) of cementite plates within the pearlite phase. The effect manifests itself to the greatest extent in the surface layer where due to the rolling the level of plastic deformation was the highest. Data of microhardness measurements confirms the gradient pattern of strain hardening over the cross section during the HR occurs while the most intensive microhardness increasing take place at the depth of up to 3 mm. According to the mechanical testing results the helical rolling of 09Mn2Si steel gives rise to increasing the level of deforming stress at the yield plateau as well as the proportionality limit with a general decrease in the relative elongation. At the same time, despite the strain hardening resulting from the helical rolling the mechanisms of plastic deformation which manifest themselves in the form of parabolic hardening with a smooth decrease in the flow stress level after neck formation are preserved in the steel. During the cyclic tension the number of cycles prior to failure increases from 2.5 to 3.8 times that depends on the location of specimens' cutting from the rolled rod. The highest improvement in fatigue fracture resistance is registered for specimens cut out from the core of the rolled rods

Dynamics of the bioclimatic potential of agroecological zones of the Altai Territory in the conditions of modern climatic and anthropogenic changes

The steppe zone is characterized by high dynamism of environmental conditions including sharp climatic fluctuations that affect both the possibilities of agriculture and the state of steppe landscapes. Further development of agriculture without taking into account changing climatic and environmental factors increases risks both for steppe ecosystems and for the sustainability of agriculture. The field production of the agro-climatic zones of the Altai Territory is characterized by the high variability of gross yields associated with the dynamics of precipitation, air temperature, and soil fertility. Under the current conditions, the analysis of the temporal and spatial dynamics of bioclimatic potential is of high practical importance for the development and implementation of adaptive agricultural technologies. A retrospective analysis was carried out and a modern bio-climatic characteristic of model territories representing various agroecological zones was compiled for this purpose. The object of research was data on average daily, average monthly, and average annual air temperatures, the level of precipitation, the water vapor pressure, and relative humidity. Statistical processing of analytical data was carried out in Excel. Calculations revealed significant temporal and spatial dynamics of the BCP. Spatially, it is characterized by a significant decrease in a north-western orientation. The lowest average values, 1.71-1.81 units, were observed in the Kulunda and Rubtsovskaya agroecological zones, with a coefficient of variation of more than 20.0%. The Zarinskaya and Aleyskaya agroecological zones were characterized by the highest values of BCP, and the Predgornaya zone presented maximum values of BCP, at the level of 2.70 units with high stability. Temporally, the BCP of the Zarinskaya, Kulunda, and Priobskaya agroclimatic zones is characterized by a negative trend; in other zones, its almost zero balance is noted. A sufficiently expressed difference in the BCP of various agroecological zones has an impact on the realization of the biological potential of cultivated crops. Analysis of the level of development of the vegetative mass of spring wheat by determining NDVI confirmed this assumption. For a systematic assessment of the influence of climatic and anthropogenic factors on the production process of field crops and the development of measures for the rational use of agricultural landscapes, it is advisable to determine the potential yield according to the BCP, determine the degree of its implementation in the economic harvest and justify techniques for leveling limiting factors in agrotechnology of individual agroecological zones

Tuning of the transverse magneto-optical Kerr effect in magneto-plasmonic crystals

The spectral properties of the transverse magneto-optical Kerr effect (TMOKE) in periodic metal–dielectric hybrid structures are studied, in particular with respect to the achievable magnitude. It is shown that the TMOKE is sensitive to the magneto-optical activity of the bismuth-substituted rare-earth iron garnet, which is used as a dielectric material in the investigated structures. For samples with larger Bi substitution level and, consequently, larger gyration constant, the magnitude of the TMOKE increases and reaches 13% in the case of a Bi1.8Lu1.2Fe3.6Al1.4O12 magnetic film. Further, it is demonstrated that the TMOKE vanishes at the high-symmetry points of the Brillouin zone (at the Γ and X points). The main enhancement of the TMOKE takes place near the resonances of the surface plasmon polaritons (SPPs) at the metal/magnetic–dielectric interface. However, near the degenerate resonances of the SPPs at the air/metal and metal/magnetic–dielectric interfaces the TMOKE is increased by the air/metal SPPs as well. This phenomenon is explained in terms of a coupled oscillator model

Plasmon-mediated magneto-optical transparency

Magnetic field control of light is among the most intriguing methods for modulation of light intensity and polarization on sub-nanosecond timescales. The implementation in nanostructured hybrid materials provides a remarkable increase of magneto-optical effects. However, so far only the enhancement of already known effects has been demonstrated in such materials. Here we postulate a novel magneto-optical phenomenon that originates solely from suitably designed nanostructured metal-dielectric material, the so-called magneto-plasmonic crystal. In this material, an incident light excites coupled plasmonic oscillations and a waveguide mode. An in-plane magnetic field allows excitation of an orthogonally polarized waveguide mode that modifies optical spectrum of the magneto-plasmonic crystal and increases its transparency. The experimentally achieved light intensity modulation reaches 24%. As the effect can potentially exceed 100%, it may have great importance for applied nanophotonics. Further, the effect allows manipulating and exciting waveguide modes by a magnetic field and light of proper polarization

Surgical outcomes in patients with drug-resistant bilateral temporal lobe epilepsy confirmed via magnetic resonance imaging

Introduction. In patients with drug-resistant temporal lobe epilepsy (TLE), surgical treatment is aimed to resect an epileptogenic zone (EZ) followed by seizure control. Despite complicated EZ location, surgical resection should be considered as a treatment of choice in bilateral TLE. Objective: to evaluate surgical outcomes and factors contributing to outcomes in patients with drug-resistant bilateral TLE confirmed via magnetic resonance imaging. Materials and methods. The study included patients with unilateral (n = 50) and bilateral (n = 50) temporal lobe involvement. The results of surgical treatment were evaluated according to the classification of J. Engel (1993). Results. Favorable outcomes of surgical treatment (Engel I and Engel II) in the group with unilateral temporal lobe involvement were found in 98% of patients after 12 months, in 88% after 24 months, and in 100% after 48 and 60 months after surgery. In the group with bilateral temporal lobe involvement outcomes of surgical treatment were favorable in 41% of patients after 12 months, in 50% after 24 months, in 39% after 48 months, and in 50% of patients after 60 months post-surgery. Conclusion. Early onset, burdened perinatal history, and MRI-confirmed left temporal lobe involvement contribute to the poor outcome (Engel III and Engel IV) in the bilateral TLE group. Engel I outcomes were more common in the patients with unilateral TLE while Engel IIIV outcomes were more common in the patients with bilateral TLE

ЭХОКАРДИОГРАФИЧЕСКИЕ ПРЕДИКТОРЫ НЕБЛАГОПРИЯТНЫХ КЛИНИЧЕСКИХ СОБЫТИЙ ПРИ СЕРДЕЧНОЙ НЕДОСТАТОЧНОСТИ С СОХРАННОЙ ФРАКЦИЕЙ ВЫБРОСА ЛЕВОГО ЖЕЛУДОЧКА В СОЧЕТАНИИ С СИНДРОМОМ ОБСТРУКТИВНОГО АПНОЭ ВО СНЕ

HighlightsRepeated hospitalizations occupy a special place in adverse clinical events in heart failure, currently representing one of the most powerful predictors of adverse outcomes in this group of patients. Echocardiographic parameters such as longitudinal myocardial deformation, displacement in the annulus of the tricuspid valve, and left atrial volume index can serve as predictors of hospitalization for cardiovascular diseases in patients with heart failure with preserved ejection fraction and obstructive sleep apnea. Abstract Aim. To study the prognostic role of individual echocardiographic parameters in heart failure with preserved ejection fraction (HFpEF) in patients with arterial hypertension and obstructive sleep apnea (OSA).Methods. The study included 59 men with hypertension and OSA (apnea/hypopnea index >15 per hour). At baseline all patients underwent a sleep study and echocardiography with an additional assessment of the global longitudinal strain (GLS). Upon inclusion in the study and after 12 months of follow-up, a 6-minute walk test was performed. After 12 months, the clinical course of the disease was retrospectively assessed. The criteria for an adverse clinical course were episodes of hospitalization for cardiovascular diseases, the development of paroxysmal atrial fibrillation or high-grade ventricular arrhythmias (III–V class according to Ryan), worsening of heart failure with a transition to a higher functional class according to NYHA.Results. Significant differences were found in several echocardiographic parameters between the groups of patients with and without hospitalizations within 12 months of follow-up: tricuspid annular plane systolic excursion (TAPSE) (p = 0.017), GLS (p = 0.005), left atrial volume index (LAVI) (p = 0.032). According to the regression analysis results, TAPSE, GLS and left ventricular ejection fraction make a statistically significant contribution to the probability of hospitalizations among the evaluated echocardiographic predictors.Conclusion. The results of the study allow us to consider certain echocardiographic parameters, in particular GLS, TAPSE and LAVI, as predictors of hospitalizations in patients with HFpEF and OSA.Основные положенияПовторные госпитализации занимают особое место в ряду клинических событий при хронической сердечной недостаточности, представляя в настоящее время один из наиболее мощных предикторов неблагоприятных исходов в этой группе. Эхокардиографические параметры – продольная деформация миокарда левого желудочка, величина смещения фиброзного кольца трикуспидального клапана и индекс объема левого предсердия – служат предикторами госпитализации в стационар по поводу сердечно-сосудистых заболеваний у больных сердечной недостаточностью с сохранной фракцией выброса и синдромом обструктивного апноэ во сне. РезюмеЦель. Изучить прогностическую роль отдельных эхокардиографических параметров при сердечной недостаточности с сохранной фракцией выброса у больных артериальной гипертензией и синдромом обструктивного апноэ во сне (СОАС).Материалы и методы. В исследование включено 59 мужчин с артериальной гипертензией и СОАС (с индексом апноэ/гипопноэ >15 в час). Всем пациентам при включении в исследование выполнены полисомнографическое исследование и эхокардиография с дополнительной оценкой глобальной продольной деформации миокарда левого желудочка (GLS). При включении в исследование и через 12 мес. наблюдения проведен тест 6-минутной ходьбы. Через 12 мес. ретроспективно оценен характер клинического течения заболевания. Критериями неблагоприятного течения являлись эпизоды госпитализации в стационар по поводу сердечно-сосудистых заболеваний, развитие пароксизмальной фибрилляции предсердий или регистрация желудочковых нарушений ритма высоких градаций (III–V класса по Ryan), ухудшение хронической сердечной недостаточности с переходом в более высокий функциональный класс по NYHA.Результаты. Обнаружены значимые различия между группами пациентов с наличием и отсутствием госпитализаций в течение 12 мес. наблюдения по ряду эхокардиографических параметров: систолическому смещению фиброзного кольца трикуспидального клапана (TAPSE) (p = 0,017), GLS (p = 0,005) и индексу объема левого предсердия (p = 0,032). По результатам регрессионного анализа, статистически значимый вклад в вероятность госпитализаций среди оцениваемых эхокардиографических предикторов вносят TAPSE, GLS и фракция выброса левого желудочка.Заключение. Результаты исследования позволяют рассматривать отдельные эхокардиографические параметры, в частности GLS, TAPSE и индекс объема левого предсердия, в качестве предикторов госпитализаций у больных сердечной недостаточностью с сохранной фракцией выброса и СОАС

Low voltage control of exchange coupling in aferromagnet-semiconductor quantum well hybridstructure

Voltage control of ferromagnetism on the nanometer scale is highly appealing for the development of novel electronic devices with low power consumption, high operation speed, reliable reversibility and compatibility with semiconductor technology. Hybrid structures based on the assembly of ferromagnetic and semiconducting building blocks are expected to show magnetic order as a ferromagnet and to be electrically tunable as a semiconductor. Here, we demonstrate the electrical control of the exchange coupling in a hybrid consisting of a ferromagnetic Co layer and a semiconductor CdTe quantum well, separated by a thin non-magnetic (Cd,Mg)Te barrier. The electric field controls the phononic ac Stark effect—the indirect exchange mechanism that is mediated by elliptically polarized phonons emitted from the ferromagnet. The effective magnetic field of the exchange interaction reaches up to 2.5 Tesla and can be turned on and off by application of 1V bias across the heterostructure

Crowdsourcing Fungal Biodiversity : Revision of Inaturalist Observations in Northwestern Siberia

The paper presents the first analysis of crowdsourcing data of all observations of fungi (including lichens) and myxomycetes in Northwestern Siberia uploaded to iNaturalist.org to date (24.02.2022). The Introduction presents an analysis of fungal diversity crowdsourcing globally, in Russia, and in the region of interest. Materials and methods describe the protocol of uploading data to iNaturalist.org, the structure of the crowdsourcing community. initiative to revise the accumulated data. procedures of data analysis, and compilation of a dataset of revised crowdsourced data. The Results present the analysis of accumulated data by several parameters: temporal, geographical and taxonomical scope, observation and identification efforts, identifiability of various taxa, species novelty and Red Data Book categories and the protection status of registered observations. The Discussion provides data on usability of crowdsourcing data for biodiversity research and conservation of fungi, including pros and contras. The Electronic Supplements to the paper include an annotated checklist of observations of protected species with information on Red Data Book categories and the protection status, and an annotated checklist of regional records of new taxa. The paper is supplemented with a dataset of about 15 000 revised and annotated records available through Global Biodiversity Information Facility (GBIF). The tradition of crowdsourcing is rooted in mycological societies around the world, including Russia. In Northwestern Siberia, a regional mycological club was established in 2018, encouraging its members to contribute observations of fungi on iNaturalist.org. A total of about 15 000 observations of fungi and myxomycetes were uploaded so far, by about 200 observers, from three administrative regions (Yamalo-Nenetsky Autonomous Okrug, Khanty-Mansi Autonomous Okrug, and Tyumen Region). The geographical coverage of crowdsourcing observations remains low. However. the observation activity has increased in the last four years. The goal of this study consisted of a collaborative effort of professional mycologists invited to help with the identification of these observations and analysis of the accumulated data. As a result, all observations were reviewed by at least one expert. About half of all the observations have been identified reliably to the species level and received Research Grade status. Of those, 90 species (195 records) represented records of taxa new to their respective regions: 876 records of 53 species of protected species provide important data for conservation programmes. The other half of the observations consists of records still under-identified for various reasons: poor quality photographs, complex taxa (impossible to identify without microscopic or molecular study). or lack of experts in a particular taxonomic group. The Discussion section summarises the pros and cons of the use of crowdsourcing for the study and conservation of regional fungal diversity, and summarises the dispute on this subject among mycologists. Further research initiatives involving crowdsourcing data must focus on an increase in the quality of observations and strive to introduce the habit of collecting voucher specimens among the community of amateurs. The timely feedback from experts is also important to provide quality and the increase of personal involvement.Peer reviewe

A Model of Critical Success Factors for Implementing Enterprise Resource Planning Packages in Higher Education

The implementation of enterprise resource planning packages has proven to be a difficult challenge in many environments. Institutions of higher education are new entrants in the field of ERPs. Colleges and universities are beginning to implement comprehensive student information systems that aim to support all areas of administrative computing including student records, student admission, accounts receivable, and financial aid. The early experiences of these implementers are similar to experiences of ERP implementers outside of higher education. Some of these implementations have failed , leaving institutions\u27 records and computerized student services in disarray. ERP researchers have so far focused on surveying implementers in industry to determine common causes of failed projects and the necessary prerequisites for successful implementations. However, colleges and universities operate in an environment that is different from that of businesses. The vast majority of them are non-profit, and they operate on small budgets within strict regulatory guidelines. Research similar to that in industry is needed to determine whether the same factors are responsible for successful and failed ERP implementations. ERP research in industry has generated consistent critical success factors. There are also factors available from research on information systems implementations in higher education. The researcher included these critical success factors in a survey that was mailed to managers of successful ERP implementations in higher education. These individuals were asked to mark each factor as necessary or not necessary in their particular implementation. They were also asked to provide additional factors. A second survey was used to validate the model. ERP implementers in higher education were asked to rank the importance of each factor relative to their particular implementation. Expectations were that ERP implementations proceed differently in colleges and universities. The list of factors obtained from the second survey can serve as a model for future ERP implementations in higher education. Future implementers of ERPs in higher education should be able to devote additional resources to those factors of ERP projects that were ranked higher in the list and fewer resources to other areas