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Stochastic analysis of an elastic 3D half-space respond to random boundary displacements : exact results and Karhunen-Loéve expansion
A stochastic response of an elastic 3D half-space to random
displacement excitations on the boundary plane is studied. We derive exact
results for the case of white noise excitations which are then used to give
convolution representations for the case of general finite correlation length
fluctuations of displacements prescribed on the boundary. Solutions to this
elasticity problem are random fields which appear to be horizontally
homogeneous but inhomogeneous in the vertical direction. This enables us to
construct explicitly the Karhunen-Loève (K-L) series expansion by solving
the eigen-value problem for the correlation operator. Simulation results are
presented and compared with the exact representations derived for the
displacement correlation tensor. This paper is a complete 3D generalization
of the 2D case study we presented in J. Stat. Physics, v.132 (2008), N6,
1071-1095
The impact of war on the development and progression of arterial hypertension and cardiovascular disease: protocol of a prospective study among Ukrainian female refugees.
Growing evidence supports the impact of psychological factors such as traumatic experiences and Post Traumatic Stress Disorder (PTSD) on the incidence of arterial hypertension (HTN) and cardiovascular diseases (CVD). The war in Ukraine is exposing million inhabitants to traumatic experiences and severe stress. Part of Ukrainians (mostly women and children) left the country to escape war. We report the protocol of a prospective study aiming at the assessment of the impact of war-induced stress on HTN and CVD in women Ukrainian refugees who moved to Poland.
The study will be conducted in 3 stages. Stage 1 will assess the prevalence of HTN and PTSD among Ukrainian refugees and will estimate the impact of war-related trauma exposure on these parameters. Data on office blood pressure (BP) will be compared to data already collected in STEPS data 2019 and May Measurement Month 2021 in Ukraine, matched for age and sex. Stage 2 will involve subjects diagnosed with HTN and/or PTSD referred for management and follow-up of these conditions. Psychologic targeted therapies will be offered to subjects with confirmed PTSD, with a periodical reassessment of the severity of PTSD-associated symptoms and of its impact on HTN and cardiovascular health. Clinical history and characteristics will be compared among three groups: subjects with HTN and PTSD, with HTN without PTSD, with PTSD but without HTN. Stage 3 will involve a subgroup among those screened in Stage 1, with the objective of investigating the biological mechanisms underlying the relation between HTN and trauma exposure, identifying early signs of subclinical target organ damage in subjects with HTN with/without PTSD.
This study will test the hypothesis that trauma exposure and psychological stress contribute to BP elevation and progression of CVD in this population. It will provide new evidence on the effect of an integrated management, including psychological therapy, on BP and cardiovascular risk. Such approach may be further tested and extrapolated to other populations exposed to war and chronic violence, migrants and refugees around the world.
number 2022/45/P/NZ5/02812
The Role of Genetic Polymorphism in the Formation of Arterial Hypertension, Type 2 Diabetes and their Comorbidity
Background: Hereditary component plays a significant role in the formation of insulin resistance (IR) - one of the pathogenetic links of arterial
hypertension (AH) and type 2 diabetes mellitus (DM2). However, the genetic predisposition to IR can not be realized and does not manifest itself
clinically in the absence of appropriate factors of the environment (excessive nutrition, low physical activity, etc.).
Objective: The review summarizes the results of studies which describe the contribution of genetic polymorphism to the formation and progression
of AH, DM2 and their comorbidity in various populations.
Results: In many studies, it has been established that genetic polymorphism of candidate genes is influenced by the formation, course and
complication of AH and DM2. According to research data, the modulating effect of polymorphism of some genetic markers of AH and DM2 on
metabolism and hemodynamics has been established. The results of numerous studies have shown a higher frequency of occurrence of AH and
DM2, as well as their more severe course with adverse genetic polymorphisms. At the same time, the role of genetic polymorphism in the
formation of AH and DM2 differs in different populations.
Conclusion: Contradictory data on the influence of gene polymorphisms on the formation of AH and DM2 in different populations, as well as a
small number of studies on the combined effects of several polymorphisms on the formation of comorbidity, determine the continuation of
research in this direction
Hemodynamic and metabolic disorders in obese patients with resistant hypertension
Patients with resistant hypertension differed from hypertensive obese patients without resistance with higher BMI and BP, higher levels of triglycerides, insulin, HbA1c, more pronounced IR, cardiovascular remodeling, imbalance of oxidative stress - antioxidant protection system, higher proinflammatory and RAAS activity. Patients with true resistance differed from pseudo-resistant patients with significantly lower BMI, higher aldosterone levels, more pronounced imbalance of the system of oxidative stress - antioxidant protection and less pronounced adipokines imbalance
Modern approach to complex treatment of diabetic foot syndrome in a surgical hospital
139 patients exposed to surgical interventions concerning the diabetic foot syndrome (DFS) from 2013 to 2015 were analyzed in this article. They were divided in two groups: patients with neuropathic (n=60) and neuroischemic (n=79) types of DFS. The dependence of surgical treatment results from the prevalence of purulent-necrotic processes was evaluated. The tendency of decrease of major amputations was established.В статье проанализированы 139 пациентов, которым выполнены хирургические вмешательства по поводу синдрома диабетической стопы (СДС) в период с 2013-го по 2015 год. Выделены 2 группы: пациенты с нейропатическим (n=60) и нейроишемическим (n=79) типами СДС. В ходе работы была оценена зависимость исходов операций от распространенности гнойно-некротических процессов, а также была установлена тенденция к уменьшению количества больших ампутаций
Experimental Observation of Plasma Wakefield Growth Driven by the Seeded Self-Modulation of a Proton Bunch
We measure the effects of transverse wakefields driven by a relativistic proton bunch in plasma with densities of 2.1 x 10(14) and 7.7 x 10(14) electrons/cm(3). We show that these wakefields periodically defocus the proton bunch itself, consistently with the development of the seeded self-modulation process. We show that the defocusing increases both along the bunch and along the plasma by using time resolved and time-integrated measurements of the proton bunch transverse distribution. We evaluate the transverse wakefield amplitudes and show that they exceed their seed value (< 15 MV/m) and reach over 300 MV/m. All these results confirm the development of the seeded self-modulation process, a necessary condition for external injection of low energy and acceleration of electrons to multi-GeV energy levels
Experimental Observation of Proton Bunch Modulation in a Plasma at Varying Plasma Densities
We give direct experimental evidence for the observation of the full transverse self-modulation of a long, relativistic proton bunch propagating through a dense plasma. The bunch exits the plasma with a periodic density modulation resulting from radial wakefield effects. We show that the modulation is seeded by a relativistic ionization front created using an intense laser pulse copropagating with the proton bunch. The modulation extends over the length of the proton bunch following the seed point. By varying the plasma density over one order of magnitude, we show that the modulation frequency scales with the expected dependence on the plasma density, i.e., it is equal to the plasma frequency, as expected from theory
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