Near-field characterization of conductive micro-resonators for terahertz sensing

Near-field (NF) terahertz (THz) time-domain spectroscopy (TDS) is an excellent tool for direct studies of THz electromagnetic resonances occurring on a micrometre scale. Micro-resonators are at the heart of numerous promising THz sensing and detecting solutions. Experimental studies of individual micrometrescale THz resonances are essential, yet extremely challenging for the common far-field spectroscopic methods due to extreme sensitivity requirements. NF THz spectroscopy and microscopy are non-contact techniques for spectroscopic studies of individual micro-resonators and mapping the field patterns of THz resonant modes excited in individual conductive or insulating micro-objects. They give access to essential parameters of micro-resonators, including their resonance frequency, local field enhancement and quality factors. It allows for material and structural characterisation of micro-objects. Using the example of carbon microfibres, we show the advantages of NF THz TDS for non-contact THz conductivity probing and direct observation of the fundamental and the third-order surfaceplasmon resonance modes in conductive THz micro-resonators

Hybrid Systems of Soft Computing Technologies in Designing Team Decision for Supply Chain Management Systems of Organizations

Abstract—The main objective is development of hybrid systems for adaptive designing and supply chain management / strategizing of team decision “packages” for design work based on the use of soft computing technologies and system-creative thinking (SCT). An algorithm is proposed, and the results of case studies on predicting the effectiveness and optimal organization of team thinking, as well as designing team solutions using the technical package of social technologies are presented. They are exemplified by developing a system of products and marketing channels (points of contact) of an employer brand (EB) of an organization for individual stakeholder groups. An algorithm has been developed for using a system of hybrid “soft computing” technologies and system-creative thinking in supply chain process of project teamwork; practical calculations have been carried out using this algorithm. The algorithm and systems of models for using “soft computing” for supply chain developed allow us to obtain a synergistic effect from controlling a system of hybrid technologies at various stages of teamwork. The package includes a “basic” technology comprising “training teams”, and also the formation of a KPI system that characterize team work (units 1 and 2), “product” technologies comprising analysis of team organization thinking, forecasting team performance, team productivity management, as well as supply chain management of project (units 4, 5, 6), and also “closing” technology being a strategizing (adaptive management) of team work (dynamic control of the algorithm as a whole)

Поняття та види завдань органів прокуратури України щодо протидії корупції

Хромова, К. Поняття та види завдань органів прокуратури України щодо протидії корупції / Катерина Хромов // Підприємництво, господарство і право. - 2016. - № 2. - С.162-166.У статті розглянуто наявні у правознавстві погляди на зміст та сутність поняття «завдання», акцентовано увагу на їх перевагах та недоліках, зроблено відповідні висновки. Проаналізовано точки зору щодо співвідношення понять «мета діяльності» та «завдання». З’ясовано, що такі категорії, як «мета» та «завдання» мають дуже тісний взаємозв’язок, обумовлюють одна одну під час прак-тичної діяльності органів прокуратури України у сфері протидії корупції.The article considers the views available in jurisprudence on the content and essence of the concept of "task", focuses on their advantages and disadvantages, draws appropriate conclusions. Perspectives on the relationship between the concepts of "purpose of activity" and "task" are analyzed. It was found that such categories as "goal" and "task" have a very close relationship, determine each other during the practical activities of the prosecutor's office of Ukraine in the field of anti-corruption.В статье рассмотрены имеющиеся в правоведении взгляды на содержание и сущность понятия «задача», акцентировано внимание на их преимуществах и недостатках, сделаны соответствующие выводы. Проанализированы точки зрения относительно соотношения понятий «цель деятельности» и «задачи». Выяснено, что такие категории, как «цель» и «задача» имеют очень тесную взаимосвязь, обусловливают друг друга во время прак-тической деятельности органов прокуратуры Украины в сфере противодействия коррупции

Dipolar resonances in conductive carbon micro-fibers probed by near-field terahertz spectroscopy

We observe dipole resonances in thin conductive carbon micro-fibers by detecting an enhanced electric field in the near-field of a single fiber at terahertz (THz) frequencies. Time-domain analysis of the electric field shows that each fiber sustains resonant current oscillations at the frequency defined by the fiber's length. Strong dependence of the observed resonance frequency and degree of field enhancement on the fibers' conductive properties enable direct non-contact probing of the THz conductivity in single carbon micro-fibers. We find the conductivity of the fibers to be within the range of 1– 5×104 S/m. This approach is suitable for experimental characterization of individual doped semiconductor resonators for THz metamaterials and devices

Possibilities of noninvasive diagnostics of cardiovascular diseases associated with atherosclerosis

Background. Despite the global trend towards a decrease in mortality from cardiovascular pathology of atherosclerotic genesis, this group of diseases continues to occupy a leading position in the structure of disability and mortality among the population of many countries. Aim. Identification of noninvasive markers of arterial wall lesions associated with the presence of arterial hypertension (AH) and coronary heart disease (CHD) in persons younger than 55 years. Materials and methods. The study included 81 people. Three groups were distinguished from them: 1st (n=31) – a control group of practically healthy individuals, average age – 43 (40; 48) years; 2nd group (n=21) – patients with coronary heart disease without a history of cardiovascular diseases (CVD), average age – 45,5±6,1; group 3 (n=29) – patients with AH without CHD, average age – 47 (35; 50) years. The parameters of a biochemical blood test were determined, volumetric sphygmography and a sample with post-occlusive reactive hyperemia were performed. Results. In groups of patients with CHD and AH, negative changes in the lipid profile and higher glucose levels were recorded compared to healthy individuals. According to the results of volumetric sphygmography, the pulse wave velocity in arteries of predominantly elastic type (R/L-PWV) in group 1 was 10.1±1.7 m/s, in group 2 – 12.9±1.8 m/s, in group 3 – 13.1 (12; 14) m/s (р1–2=0.029; р1–30.001); cardio-ankle vascular index (CAVI) – 6.5±0.7, 7.7 (7; 8.7) and 7.8 (7.3; 8.4), respectively (р1–20.001; р1–30.001). According to the data of the test with post-occlusive reactive hyperemia, a comparably high frequency of pathological values of flow-dependent vasodilation (FDV) and reactivity index (RI) was demonstrated in patients with CHD and AH (р1–20.05; р1–30.05). A multifactorial model of noninvasive diagnosis of CHD in individuals without a history of CVD, including non-high-density lipoprotein cholesterol, R/L-PWV, and FDV, has been developed. For patients with AH, glucose, lipid metabolism, R/L-PWV, pulse wave velocity in muscle-type arteries (B-PWV), augmentation index (AI), biological age, CAVI, FDV, RI were the risk factors for the presence of the disease in the anamnesis. Conclusion. The results obtained confirm the importance of an integrated approach in the screening diagnosis of CVD

High-definition electrocardiography potential in identifying the reasons for unstable clinical course of coronary heart disease

Aim: To investigate the correlation between clinical and morphological characteristics of coronary heart disease (CHD) and high-definition electrocardiography (HD-ECG) parameters. Material and methods: In total, 85 patients with unstable angina and ST segment depression (ST-UA) underwent HD-ECG during the angina attack, with late ventricular potential (LVP) analysis. One-year survival data were also analysed. Post-mortem histological examination of cardiac tissue was performed in 6 patients with ST-UA. Results: The important morphologic features of ST-UA included cardiomyocyte (CMC) dystrophy, due to acute and chronic myocardial ischemia, and acute injury in the cardiac conduction areas. LVPs were registered in 27 % of the ST-UA patients, mostly among people with transient myocardial ischemia (69,57 %). In patients who previously underwent myocardial infarction, LVP prevalence was lower (28,57 %). At the early stages of hospitalization, LVP were registered in 14 patients (60,87 %), while pharmacotherapy and clinical course stabilization were associated with decreased LVP prevalence (21,74 %). The study results suggest that in patients with acute coronary syndrome, LVP registration predicts not an adverse outcome, but a better prognosis. Conclusion: ST-UA is characterised by typical changes of CMC and myocardial stroma in posterior septal area, which result in metabolic, energetic, and electrical myocardial instability. LVPs could be used as a marker of functional (ischemic) myocardial heterogeneity in patients with ST-UA. LVP registration could be associated with a better prognosis in this clinical group

Uakitite, VN, a new mononitride mineral from uakit iron meteorite (IIAB)

Uakitite was observed in small troilite–daubréelite (±schreibersite) inclusions (up to 100 µm) and in large troilite–daubréelite nodules (up to 1 cm) in Fe-Ni-metal (kamacite) of the Uakit iron meteorite (IIAB), Republic of Buryatia, Russia. Such associations in the Uakit meteorite seemed to form due to high-temperature (>1000 °C) separation of Fe-Cr-rich sulfide liquid from Fe-metal melt. Most inclusions represent alternation of layers of troilite and daubréelite, which may be a result of solid decay of an initial Fe-Cr-sulfide. These inclusions are partially resorbed and mainly located in fissures of the meteorite, which is now filled with magnetite, and rarely other secondary minerals. Phase relations indicate that uakitite is one of the early minerals in these associations. It forms isometric (cubic) crystals (in daubréelite) or rounded grains (in schreibersite). The size of uakitite grains is usually less than 5 µm. It is associated with sulfides (daubréelite, troilite, grokhovskyite), schreibersite and magnetite. Carlsbergite CrN, a more abundant nitride in the Uakit meteorite, was not found in any assemblages with uakitite. Physical and optical properties of uakitite are quite similar to synthetic VN: yellow and transparent phase with metallic luster; Mohs hardness: 9–10; light gray color with a pinky tint in reflected light; density (calc.) = 6.128 g/cm3. Uakitite is structurally related to the osbornite group minerals: carlsbergite CrN and osbornite TiN. Structural data were obtained for three uakitite crystals using the electron backscatter diffraction (EBSD) technique. Fitting of the EBSD patterns for a synthetic VN model (cubic, Fm-3m, a = 4.1328(3) Å; V = 70.588(9) Å3; Z = 4) resulted in the parameter MAD = 0.14–0.37° (best-good fit). Analytical data for uakitite (n = 54, in wt. %) are: V, 71.33; Cr, 5.58; Fe, 1.56; N, 21.41; Ti, below detection limit (<0.005). The empirical formula (V0.91Cr0.07Fe0.02)1.00N1.00 indicates that chromium incorporates in the structure according to the scheme V3+ → Cr3+ (up to 7 mol. % of the carlsbergite end-member). © 2020 by the authors. Licensee MDPI, Basel, Switzerland.Russian Foundation for Basic Research, RFBR: 17-05-00129, IGM SD 0330-2016-0005Government Council on Grants, Russian FederationMinistry of Science and Higher Education of the Russian FederationFunding: The investigations were partly supported by RFBR (grant 17-05-00129) and the State assignment project (IGM SD 0330-2016-0005). This work was also supported by the Initiative Project of Ministry of Science and Higher Education of the Russian Federation and by Act 211 of the Government of the Russian Federation, agreement no. 02.A03.21.0006