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Design of broadband terahertz vector and vortex beams: II. Holographic assessment

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Light(Advanced Manufacturing) 2022年第4期3卷 14-26页

In this paper,we demonstrate the capabilities of the terahertz pulse time-domain holography in visualisation,simulation,and assessment of broadband THz vortex beam formation dynamics upon its shaping by elements of beam converter,and further propagation and *** adding Jones matrix formalism to describe broadband optical elements,we highlight the differences in the spatio-spectral and spatio-temporal structure of the formed vortex and vector beams dependence on the modulator used and visualise their modal *** influence of diffraction field structure from each element in the broadband vortex modulator is revealed in numerical simulation and the formed beams are analysed against the simplified Laguerre-Gaussian beam model.

关键词： Terahertz radiation Vortex beams Vector beams Achromatic wave plates Broadband terahertz radiation Digital holography Terahertz holography

Effect of interferon alpha and ribavirin treatment on serum levels of transforming growth factor-β1,vascular endothelial growth factor,and basic fibroblast growth factor in patients with chronic hepatitis C

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World Journal of Gastroenterology 2006年第6期12卷 961-965页

作者： Ewa Janczewska-Kazek bogdan Marek Dariusz Kajdaniuk Halina BorgieI-Marek Department of Infectious Diseases Medical University of Silesia Chorzow Poland Department of Pathophysiology Medical University of Silesia Zabrze Poland Medical University of Silesia KatowicePoland

AIM： To assess the role of transforming growth factor-β1 （TGF-β1）, vascular endothelial growth factor （VEGF） and basic fibroblast growth factor （bFGF） in the pathogenesis of fibrosis associated with chronic hepatitis C （CHC） and to evaluate the influence of the antiviral therapy on above parameter levels depending on the treatment results （complete response or no response）. METHODS： Study group included 100 patients with CHC, in whom fibrosis in liver specimens was assessed （Scheuer fibrosis score： 1-4 points）. Control group included 30 subjects with antibodies anti-HCV present and persistently normal ALT level, without fibrosis （Scheuer fibrosis score： 0 points）. Concentration of studied parameters was assayed in the serum by immunoenzymatic method before and after the therapy with interferon alpha-2b and ribavirin. RESULTS： TGF-β1 levels were significantly higher in the study group compared to the control group （35.89 vs 32.37 ng/mL; P= 0.023）. Such differences were not found in VEGF and bFGF levels. In patients showing complete response （negative HCV RNA and normal ALT level）, significant increase in VEGF （112.8 vs 315.03 pg/mL; P〈 0.05） and bFGF （2.51 vs 15.79 pg/mL; P=0.04） levels were found. Significant decrease in TGF-β1 level was observed both in responders （37.44 vs 30.02 ng/mL; P=0.05）, and in non-responders （38.22 vs 30.43 ng/mL; P=0.043）. bFGF levels before the treatment were significantly lower （2.51 vs 5.94 pg/mL; P=0.04）, and after the treatment significantly higher （15.79 vs 4.35 pg/mL; P=0.01） in patients with complete response response. CONCLUSION： Among the analyzed parameters TGF-β1 seems to play the most important role in the pathogenesis of fibrosis in CHC. Levels of this factor are significantly lower in subjects who do not have fibrosis developed in them. Good therapeutic effect in CHC patients is associated with significant changes in TGF-β1, VEGF, and bFGF levels, bFGF seems to have the highest usefulness in the prognosis of treatment

关键词： Liver fibrosis HCV Interferon Ribavirin Growth factor

Effect of Xylazine-Ketamine Anesthesia on Blood ACTH, Cortisol, Adrenaline, Insulin and Glucose in Ovariohysterectomized Cats

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Journal of Life Sciences 2015年第5期9卷 248-253页

作者： Nadya Zlatozareva Zlateva-Panayotova bogdan Yanev Aminkov Department of Surgery Anesthesiology and Radiology Faculty of Veterinary Medicine University of Forestry Sofia 1505 Bulgaria

A study has been carried out with fourteen healthy mature cats in order to determine the effect of a xylazine-ketamine anesthetic protocol （group X/K） on blood concentrations of adrenaline, ACTH （adrenocorticotropic hormone）, cortisol, insulin and glucose in comparison with a control group （group K--no anesthesia and surgery）. The animals were randomly allocated in two groups （n = 7）. The premeditation in the experimental group was made with xylazine 2 mg/kg intramuscularly. Induction and maintenance of anesthesia were made with ketamine 10 mg/kg intramuscularly. Ovariohysterectomy was performed upon occurrence of deep anesthesia. Blood specimens were obtained at 0, 30, 60, 120 min and 24 h from the two groups. Pronounced decrease in blood ACTH, cortisol, and adrenaline in group X/K was determined by the 30 min. Significant hyperglycemia together with hyperinsulinemia in the X/K group was established at the 120 min from the beginning of the anesthesia. Anesthesia with xylazine and ketamine led to reduction of the blood levels of stress hormones immediately after the beginning of anesthesia and caused a remarkable hyperglycemia with hyperinsulinemia.

关键词： Anesthesia cats adrenaline cortisol ACTH insulin.

Paleosols from North Part of Barlad City （Romania）

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Journal of Earth Science and Engineering 2012年第2期2卷 71-76页

作者： Daniel Bejan bogdan Gabriel Ratoi Mihai Branzila Department of Geology Faculty of Geography and Geology Alexandru loan Cuza University of lasi Iasi 700505 Romania

The loess deposits comprise several paleosol layers reflecting alternation of drier and wetter climate during Quaternary. Such a situation occurs in north of Barlad, on The Sohodau＇s Hill. Morphological study of the quarry paleosols from north of Barlad was accomplished based on field observations and macroscopic physic-chemical results. Three levels of paleosols with variable thickness were determined. These three fossils layers are interbedded by four loess deposits. The physical-chimical data provide important information for the paleosol genesis and depositional/climatic environments. The carbon content and C/N ratio indicate the strength of pedogenesis in the Pleistocene and trends of biomass accumulation.

关键词： Paleosols loess deposits pedogenesis quaternary.

Central Glutamatergic-Purinergic System Importance in Brain/Neural Plasticity

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Journal of Behavioral and Brain Science 2017年第7期7卷 259-272页

作者： bogdan Feliks Kania Danuta Wronska Dorota Zieba Veterinary Institute University Center for Veterinary MedicineJagiellonian University&Agriculture UniversityCracowPoland Department of Physiology and Endocrinology of Animals Faculty of Animal SciencesHugon Kollataj Agricultural University in CracowCracowPoland Department of Animal Biotechnology Faculty of Animal SciencesHugon Kollataj Agricultural University in CracowCracowPoland

The proteolysis of the extracellular matrix plays a key role in the synaptic neuroplasticity of the central nervous system (CNS), which results in learning and memory. Proteases from the serine family and metalloproteinases of the extracellular matrix are localized within the synapses and are released into the extracellular space in proportion to the degree of neuronal excitation. These enzymes cause changes in the morphology, shape and size, and the overall number of synapses and synthesize new synaptic connections. The proteinase also changes the function of receptors, and consequently, the secretion of neurotransmitter/neuromodulator from the presynaptic glutamatergic and/or purinergic elements are either strengthened or weakened. Neuroglia involved in homeostasis, melanin synthesis and defense of the brain contain different combinations of purinergic receptors, which contributes to many neurotransmitters. This review summarizes a concept of brain plasticity, the role of ATP and P2 receptors interaction with glutamatergic system during plasticity of the brain in the one hand and after physical exercise in the other, which may be triggering phenomena facilitative synaptic plasticity as well as potentiates an personal efficiency to react to biobehavioral adaptation and disorders.

关键词： Glutamatergic/Purinergic System Neuroplasticity Physical Exercise Neuroglia Dependences

Introduction to Neural Plasticity Mechanism

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Journal of Behavioral and Brain Science 2017年第2期7卷 41-49页

作者： bogdan Feliks Kania Danuta Wronska Dorota Zieba Veterinary Institute University Center for Veterinary Medicine Jagiellonian University&Agriculture UniversityHugon Kollataj Agricultural University in CracowCracowPoland Department of Physiology and Endocrinology of Animals Faculty of Animal SciencesHugon Kollataj Agricultural University in CracowCracowPoland Department of Animal Biotechnology Faculty of Animal SciencesHugon Kollataj Agricultural University in Cracowul.Redzina1BCracowPoland

In researches that examine neuroplasticity, many studies that are performed directly on isolated neurons in the pyramidal cells of CA1 area (CA1) and slices of the hippocampus indicate that changes occur at the molecular and cellular levels during long-term synaptic potentiation (LTP), and these changes are dependent on N-methyl-D-aspartate (NMDA) acid receptors and/or purinergic receptors. Electrophysiological studies and the chemical induction of LTP of synaptic neurotransmissions provide key evidence that LTP is dependent on the volume of Ca2+ influx through postsynaptic NMDA receptors, in addition to the subsequent activation and autophosphorylation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) and the increase in the density of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors on postsynaptic neuronal membranes. The primary peculiarity of LTP in the central nervous system (CNS) excitatory synapses is the synthesis of additional AMPA receptors in the postsynaptic elements. Furthermore, the proteolysis of the extracellular matrix (ECM) has an important role in the synaptic neuroplasticity of the CNS. Proteases from the serine family and metalloproteinases of the extracellular matrix are localized within the synapses and are released into the extracellular space in proportion to the degree of neuronal excitation. These enzymes cause changes in the morphology, shape and size, as well as the overall number of synapses and synthesize new synaptic connections. The proteinases also change the function of receptors, and consequently, the secretions of neurotransmitters from the presynaptic elements are strengthened or weakened.

关键词： Neuroplasticity Heterosynaptic Metaplasticity Subjects

Hydrodynamics of Liquid Flow in the Model of Theoretical Stage with Perfect Displacement

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Journal of Chemistry and Chemical Engineering 2011年第1期5卷 25-29页

作者： Volodymyr Maletal Vitaliy Taran bogdan Maleta Maleta Cyclic Distillation LLC Ukraine Department of Machines and Equipment National University of Food Technologies Kiev Ukraine

For the cyclic process of mass transfer in tray columns there are considered the hydrodynamic models of liquid flow during steam supply and during overflow of liquid from tray to tray. During steam supply, the hydrodynamic model is determined as perfect displacement model, and during liquid overflow, it is described as cell model. There were received the characteristics of liquid flow as follows： average residence time of liquid, degree of dispersion around the mean on the tray, number of perfect mixing cells depending on multiplication factor of exchange of liquid delay. In Y-X coordinates there is depicted a work line and theoretical stage of perfect displacement model. There were considered the conditions of mutual transfer of theoretical stage and theoretical stage with perfect displacement. The advantages of the mass transfer cyclic process to the stationary one arc stated.

关键词： mass transfer cyclic distillation theoretical stage the theoretical stage model with perfect displacement residence time

Perception and Attitude of the General Population on the Risk of Infection with SARS-CoV-2

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Journal of Biosciences and Medicines 2021年第6期9卷 1-10页

作者： Cristian Cojocaru Elena Cojocaru Steluta Radu bogdan Gurzu Medical III Department Faculty of Medicine “Grigore T. Popa” University of Medicine and Pharmacy Iasi Romania Morpho-Functional Sciences II Department Faculty of Medicine “Grigore T. Popa” University of Medicine and Pharmacy Iasi Romania Netconsult SRL Iasi Romania University of Agriculture Science and Veterinary Medicine Iasi Romania

Current state of knowledge on the impact of emotions and perceptions of the population towards the risk of infection with the SARS-CoV-2 should be the basis for disease control measures as well as for community awareness programs. Due to differences in perceptions, concerns, culture, beliefs, different populations may react differently to the same challenges. Ninety adults were interviewed, without symptoms suggestive of SARS-CoV-2 infection, using the Romanian version of the Fear of COVID-19 Scale. The emotional reactions expressed by various psychotic or mental disorders, the main actions are taken to protect against the SARS-CoV-2 infection, as well as the hypothetical illness behavior were investigated. The total score, as well as each item of the Fear of COVID-19 Scale, indicates a low-to-moderate emotional level regarding to the risk of coronavirus infection. The data are supported by the choice to be treated at home in case of illness. There are differences in perception between sexes and between professional categories (employees vs. retirees). Knowledge of social phenomena caused by major epidemiological crises such as SARS-CoV-2 infection should be the basis of education, disease prevention and control programs to avoid the occurrence of psychosocial risks in the population.

关键词： SARS-COV-2 Fear of COVID-19 Scale Psychosocial Risk Comorbidities Treatment

对离心情况下轴颈轴承的Reynolds模型推导(英文)

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工程数学学报 2013年第4期30卷 501-516页

作者： bogdan N.Nicolescu Tudor C.Petrescu 皮特什蒂大学数学系罗马尼亚

本文的主要结果是在轴颈轴承背景下两轴不叠合时离心情况下构造了一个精确Reynolds方程.该方程是在假设极半径方向的润滑膜厚度很小并考虑到接触面曲率影响的情况下得到的.与标准的Reynolds方程的相比,针对方程的系数我们得到了一个新... 详细信息

本文的主要结果是在轴颈轴承背景下两轴不叠合时离心情况下构造了一个精确Reynolds方程.该方程是在假设极半径方向的润滑膜厚度很小并考虑到接触面曲率影响的情况下得到的.与标准的Reynolds方程的相比,针对方程的系数我们得到了一个新的非线性格式.通过对圆柱坐标下的新Reynolds方程系数的泰勒级数展开以及忽略掉其四阶项,最终我们得到了标准方程的一般形式.

关键词： Reynolds方程轴颈轴承流体动力学润滑剂