139 research outputs found

    ORGANIZATION OF THE FINANCIAL MONITORING AT THE ENTERPRISES OF THE TRANSPORT COMPLEX

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    The indicators of financial stability of the transport company, the role of financial recovery in the system of crisis management of the organization have been considered. The essence, goals and objectives of financial recovery have been analyzed. Methodological approaches to assessing the solvency of transport enterprises as part of the analysis of their financial and production activities have been proposed. The features of the management of the transport organization in conditions of uncertainty and risk have been revealed. The main causes of insolvency of transport companies have been considered. The factors influencing the formation of the financial policy of the enterprises of the transport complex have been traced. The importance of assessing the long-term prospects for the development of the enterprise, analyzing its capabilities, and the influence of external factors has been emphasized. The stages of improving the system of financial monitoring by a transport organization have been highlighted

    Micromagnetic Structures near a Second Order Phase Transition in Monocrystalline Ferrite Garnet Plates

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    The main parameters of micromagnetic structure formation in a vicinity of a second order phase transition were determined experimentally and theoretically. The theoretical study was performed using micromagnetic approach. External magnetic field HcH_{c} of appearance of micromagnetic structure and micromagnetic structure period LcL_{c} were determined for (001)-oriented plate with uniaxial KuK_{u} and cubic K₁ magnetic anisotropy. The plate was saturated by the field applied in its plane. In the model we assumed that magnetization vector undergoes small deviations from equilibrium if magnetic field is slightly reduced. These deviations are periodic in nature: micromagnetic structure has a form of a plane wave. Dependences of HcH_{c} and LcL_{c} on an azimuthal angle of external magnetic field and on anisotropy constants KuK_{u} and K₁ were derived analytically in this work. Experimental studies of micromagnetic structure near the second order phase transition were conducted on (EuEr)₃(FeGa)₅O₁₂ (001)-oriented 50 μm thick ferrite-garnet plate with KuK_{u} = 5700 erg/cm³ and K₁=-3700 erg/cm³. Micromagnetic structure was revealed by means of magnetooptic Faraday effect. The in-plane field was increased up to 2000 Oe. Experimentally determined values of HcH_{c} and LcL_{c} were compared with theoretical estimates

    Electronic Structure of the Complex Hydride NaAlH4

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    Density functional calculations of the electronic structure of the complex hydride NaAlH4 and the reference systems NaH and AlH3 are reported. We find a substantially ionic electronic structure for NaAlH4, which emphasizes the importance of solid state effects in this material. The relaxed hydrogen positions in NaAlH4 are in good agreement with recent experiment. The electronic structure of AlH3 is also ionic. Implications for the binding of complex hydrides are discussed.Comment: 4 pages, 5 figure

    Conical refraction with low-coherence light sources

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    We report on conical refraction (CR) with low-coherence light sources, such as light-emitting diodes and decoherentized HeNe laser radiation, and demonstrate different CR patterns. In our experiments, a variation of the pinhole sizes from 25 to 100 µm and the distances to pinhole from 50 to 5 cm reduced spatial coherence of radiation that resulted in the disappearance of the dark Poggendorff’s ring in the Lloyd’s plane. This is attributed to the interference nature of the Lloyd’s distribution and found to be in excellent agreement with the paraxial dual-cone model of conical refraction

    Blue-detuned optical ring trap for Bose-Einstein condensates based on conical refraction

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    We present a novel approach for the optical manipulation of neutral atoms in annular light structures produced by the phenomenon of conical refraction occurring in biaxial optical crystals. For a beam focused to a plane behind the crystal, the focal plane exhibits two concentric bright rings enclosing a ring of null intensity called the Poggendorff ring. We demonstrate both theoretically and experimentally that the Poggendorff dark ring of conical refraction is confined in three dimensions by regions of higher intensity. We derive the positions of the confining intensity maxima and minima and discuss the application of the Poggendorff ring for trapping ultra-cold atoms using the repulsive dipole force of blue-detuned light. We give analytical expressions for the trapping frequencies and potential depths along both the radial and the axial directions. Finally, we present realistic numerical simulations of the dynamics of a 87Rb Bose-Einstein condensate trapped inside the Poggendorff ring which are in good agreement with corresponding experimental results

    Geographical Variation in Egg Mass and Egg Content in a Passerine Bird

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    Reproductive, phenotypic and life-history traits in many animal and plant taxa show geographic variation, indicating spatial variation in selection regimes. Maternal deposition to avian eggs, such as hormones, antibodies and antioxidants, critically affect development of the offspring, with long-lasting effects on the phenotype and fitness. Little is however known about large-scale geographical patterns of variation in maternal deposition to eggs. We studied geographical variation in egg components of a passerine bird, the pied flycatcher (Ficedula hypoleuca), by collecting samples from 16 populations and measuring egg and yolk mass, albumen lysozyme activity, yolk immunoglobulins, yolk androgens and yolk total carotenoids. We found significant variation among populations in most egg components, but ca. 90% of the variation was among individuals within populations. Population however explained 40% of the variation in carotenoid levels. In contrast to our hypothesis, we found geographical trends only in carotenoids, but not in any of the other egg components. Our results thus suggest high within-population variation and leave little scope for local adaptation and genetic differentiation in deposition of different egg components. The role of these maternally-derived resources in evolutionary change should be further investigated.Peer reviewe

    Geographical trends in the yolk carotenoid composition of the pied flycatcher (Ficedula hypoleuca)

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    Carotenoids in the egg yolks of birds are considered to be important antioxidants and immune stimulants during the rapid growth of embryos. Yolk carotenoid composition is strongly affected by the carotenoid composition of the female’s diet at the time of egg formation. Spatial and temporal differences in carotenoid availability may thus be reflected in yolk concentrations. To assess whether yolk carotenoid concentrations or carotenoid profiles show any large-scale geographical trends or differences among habitats, we collected yolk samples from 16 European populations of the pied flycatcher, Ficedula hypoleuca. We found that the concentrations and proportions of lutein and some other xanthophylls in the egg yolks decreased from Central Europe northwards. The most southern population (which is also the one found at the highest altitude) also showed relatively low carotenoid levels. Concentrations of β-carotene and zeaxanthin did not show any obvious geographical gradients. Egg yolks also contained proportionally more lutein and other xanthophylls in deciduous than in mixed or coniferous habitats. We suggest that latitudinal gradients in lutein and xanthophylls reflect the lower availability of lutein-rich food items in the northern F. hypoleuca populations and in montane southern populations, which start egg-laying earlier relative to tree phenology than the Central European populations. Similarly, among-habitat variation is likely to reflect the better availability of lutein-rich food in deciduous forests. Our study is the first to indicate that the concentration and profile of yolk carotenoids may show large-scale spatial variation among populations in different parts of the species’ geographical range. Further studies are needed to test the fitness effects of this geographical variation

    It is time to define an organizational model for the prevention and management of infections along the surgical pathway: a worldwide cross-sectional survey

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    Background The objectives of the study were to investigate the organizational characteristics of acute care facilities worldwide in preventing and managing infections in surgery; assess participants' perception regarding infection prevention and control (IPC) measures, antibiotic prescribing practices, and source control; describe awareness about the global burden of antimicrobial resistance (AMR) and IPC measures; and determine the role of the Coronavirus Disease 2019 pandemic on said awareness. Methods A cross-sectional web-based survey was conducted contacting 1432 health care workers (HCWs) belonging to a mailing list provided by the Global Alliance for Infections in Surgery. The self-administered questionnaire was developed by a multidisciplinary team. The survey was open from May 22, 2021, and June 22, 2021. Three reminders were sent, after 7, 14, and 21 days. Results Three hundred four respondents from 72 countries returned a questionnaire, with an overall response rate of 21.2%. Respectively, 90.4% and 68.8% of participants stated their hospital had a multidisciplinary IPC team or a multidisciplinary antimicrobial stewardship team. Local protocols for antimicrobial therapy of surgical infections and protocols for surgical antibiotic prophylaxis were present in 76.6% and 90.8% of hospitals, respectively. In 23.4% and 24.0% of hospitals no surveillance systems for surgical site infections and no monitoring systems of used antimicrobials were implemented. Patient and family involvement in IPC management was considered to be slightly or not important in their hospital by the majority of respondents (65.1%). Awareness of the global burden of AMR among HCWs was considered very important or important by 54.6% of participants. The COVID-19 pandemic was considered by 80.3% of respondents as a very important or important factor in raising HCWs awareness of the IPC programs in their hospital. Based on the survey results, the authors developed 15 statements for several questions regarding the prevention and management of infections in surgery. The statements may be the starting point for designing future evidence-based recommendations. Conclusion Adequacy of prevention and management of infections in acute care facilities depends on HCWs behaviours and on the organizational characteristics of acute health care facilities to support best practices and promote behavioural change. Patient involvement in the implementation of IPC is still little considered. A debate on how operationalising a fundamental change to IPC, from being solely the HCWs responsibility to one that involves a collaborative relationship between HCWs and patients, should be opened
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