Profile Stiffness Research Articles

Coagulation Profile and Clot Stiffness Analysis from COVID-19-Positive Patients Using a Contactless Viscoelasticity Testing Technology

Coagulation Profile and Clot Stiffness Analysis from COVID-19-Positive Patients Using a Contactless Viscoelasticity Testing Technology

Revisiting Mac-2-Binding Protein Glycosylation Isomer (M2BPGi) for Diagnosing High-Risk Liver Fibrosis in Chronic Hepatitis B Patients: A Stepwise Diagnostic Analysis.

The level of liver fibrosis is the basis for the treatment of chronic hepatitis B (CHB), and it is necessary to adapt non-invasive liver fibrosis modalities. We aimed to investigate the use of M2BPGi as a single or combined diagnostic modality for liver fibrosis in CHB patients through a stepwise diagnostic analysis. Cross-sectional data were taken from patients between October 2021 and August 2022. Demographic data, blood profile, liver function, and liver stiffness were measured in CHB patients over 18 years old, willing to take part in the research, and had complete data. APRI, FIB-4, and AAR were calculated using the well-known formulas. Serum M2BPGi-levels were converted into a cut-off index (COI). The patients were divided into low-risk (LR) and high-risk fibrosis (HR) groups. A cut-off for each predictor variable to differentiate between the LR and HR groups was determined. The obtained cut-off was assessed for its association with the grouping of liver elastography results. Models to diagnose the liver stiffness measurement (LSM) ≥8 kPa were created and compared through multivariate and ROC analyses. The number of patients that met the inclusion and exclusion criteria was 143 (HR = 65, LR = 78). The cut-off for diagnosing LSM ≥8kPa was 0.311, 0.742, 0.635, and 1.434 for APRI, FIB-4, AAR, and M2BPGi, respectively. This cut-off was significantly associated with the results of the HR and LR groupings. A multivariate analysis found that FIB4, AAR, and M2BPGi added significantly to the model. Statistically, the most optimal use of M2BPGi was combined with FIB-4, with an AUC of 0.835. The optimal cut-off of M2BPGi for diagnosing high-risk liver fibrosis in this study was 1.434. M2BPGi should be used with FIB-4 as a diagnostic tool for diagnosing liver fibrosis, especially in the absence of a liver biopsy or elastography.

Revisiting Mac-2-Binding Protein Glycosylation Isomer (M2BPGi) for Diagnosing High-Risk Liver Fibrosis: A Stepwise Diagnostic Analysis

Abstract* Background The level of liver fibrosis is the basis for the treatment of chronic hepatitis B (CHB), and it is necessary to adapt non-invasive liver fibrosis modalities. We aimed to investigate the use of M2BPGi as a single or combined diagnostic modality for liver fibrosis in CHB patients through a stepwise diagnostic analysis. Methods Cross-sectional data were taken from patients between October 2021 and August 2022. Demographic data, blood profile, liver function, and liver stiffness were measured in CHB patients over 18 years old, willing to take part in the research, and had complete data. APRI, FIB-4, and AAR were calculated using the well-known formulas. Serum M2BPGi-levels were converted into a cut-off index (COI). The patients were divided into low-risk (LR) and high-risk fibrosis (HR) groups. A cut-off for each predictor variable to differentiate between the LR and HR groups was determined. The obtained cut-off was assessed for its association with the grouping of liver elastography results. Models to diagnose the liver stiffness measurement (LSM) ≥8 kPa were created and compared through multivariate and ROC analyses. Results The number of patients that met the inclusion and exclusion criteria was 143 (HR = 65, LR = 78). The cut-off for diagnosing LSM ≥8kPa was 0.311, 0.742, 0.635, and 1.434 for APRI, FIB-4, AAR, and M2BPGi, respectively. This cut-off was significantly associated with the results of the HR and LR groupings. A multivariate analysis found that FIB4, AAR, and M2BPGi added significantly to the model. Statistically, the most optimal use of M2BPGi was combined with FIB-4, with an AUC of 0.835. Conclusions The optimal cut-off of M2BPGi for diagnosing high-risk liver fibrosis in this study was 1.434. M2BPGi should be used with FIB-4 as a diagnostic tool for diagnosing liver fibrosis, especially in the absence of a liver biopsy or elastography.

Impact of T i/T e ratio on ion transport based on EAST H-mode plasmas

At the EAST tokamak, the ion temperature (T i) is observed to be clamped around 1.25 keV in electron cyclotron resonance (ECR)-heated plasmas, even at core electron temperatures up to 10 keV (depending on the ECR heating power and the plasma density). This clamping results from the lack of direct ion heating and high levels of turbulence-driven transport. Turbulent transport analysis shows that trapped electron mode and electron temperature gradient-driven modes are the most unstable modes in the core of ECR-heated H-mode plasmas. Nevertheless, recently it was found that the T i/T e ratio can increase further with the fraction of the neutral beam injection (NBI) power, which leads to a higher core ion temperature (T i0). In NBI heating-dominant H-mode plasmas, the ion temperature gradient-driven modes become the most unstable modes. Furthermore, a strong and broad internal transport barrier (ITB) can form at the plasma core in high-power NBI-heated H-mode plasmas when the T i/T e ratio approaches ~1, which results in steep core T e and T i profiles, as well as a peaked n e profile. Power balance analysis shows a weaker T e profile stiffness after the formation of ITBs in the core plasma region, where T i clamping is broken, and the core T i can increase further above 2 keV, which is 80% higher than the value of T i clamping in ECR-heated plasmas. This finding proposes a possible solution to the problem of T i clamping on EAST and demonstrates an advanced operational regime with the formation of a strong and broad ITB for future fusion plasmas dominated by electron heating.

Formation, propagation and conversion of transport barriers triggered by dynamical critical gradient in tokamak plasmas

In this work, we propose a reduced model with a dynamical critical gradient to study the formation, propagation, and conversion of the transport barriers. In contrast to the commonly adopted static critical gradient, an evolving critical gradient self-consistently softens the profile stiffness, so as to facilitate the generation of transport barriers. This is especially crucial to the internal transport barrier (ITB) formation. Numerically, we show that the inhomogeneity of turbulent and neoclassical diffusivities can induce the global wave front propagation of the transport barrier. When the heating power ramps quickly, the ITB propagates unidirectionally to the edge region and converts into an edge transport barrier. For slow power ramping, the propagating ITB will bifurcate into bidirectional wavefronts and finally convert into a steady double transport barrier state. Our model uncovers the vital role of a dynamical ‘profile-stiffness’ in depicting the global dynamics of the transport barrier.

Показатели суточного мониторинга артериального давления у лиц старческого возраста c хронической сердечной недостаточностью в зависимости от жесткости сосудов

INTRODUCTION: Measurement of arterial pressure (AP) is a standard method for assessing the risk of developing cardiovascular diseases. Analysis of systolic and diastolic pressure, as well as their ratio, can help determine the risk of developing cardiovascular diseases. One of the ways to diagnose elevatedarterial pressure is daily monitoring of arterial pressure (DMAP). An increase in AP in the elderly is usually associated with an increase in the stiffness of the vascular walls. This leads to an increase in systolic arterial pressure (SAP) and pulse pressure (PP), as well as a decrease in diastolic arterial pressure (DAP). Elevated arterial pressure enhances the load on the heart and can lead to its pathological alterations. A decrease in DAP impairs the blood supply to the heart, which can cause ischemia and fibrosis; the result isdevelopment of diastolic dysfunction, which is the main cause of chronic heart failure (CHF). Currently, a promising way to determine the arterial stiffness is measurement of a cardio-ankle vascular index.The prognostic and diagnostic value of this parameter has been confirmed by numerous studies. It is important to study the parameters of the daily AP profile and arterial stiffness in older patients with CHF. This permits to identify malignant forms of elevated blood pressure, which can lead to cardiovascular complications. AIM: To study the characteristics of the parameters of the daily arterial pressure profile in elderly patients with CHF, depending on the vascular stiffness determined by volume sphygmography. MATERIALS AND METHODS: One hundred and twenty elderly patients with CHF undergoing treatment in a cardiology hospital were examined. By the method of volume sphygmography, the patients were divided into groups with ‘vessels of normal stiffness’ (group 1) and ‘stiff vessels’ (group 2), with subsequentDMAP. A statistical analysis of the parameters of the daily AP profile in the groups was performed. RESULTS: In patients of group 1, both daytime and nighttime SAP, DAP and PP, were significantly higher than in patients of group 2. Besides, in group 1, there was a nighttime decrease in SAP and DAP, while the morning rise of SAP was statistically higher in group 2, and no differences were recorded between the groups in the morning rise of DAP. When assessing the ankle-brachial index in patients of group 2, daytime and nighttime SAP and DAP were statistically higher. In group 1 (with probable peripheral atherosclerosis), PP was higher both during the day and at night. The nocturnal decrease in SAP was statistically higher in group 2, while the nocturnal decrease in DAP prevailed in group 1. The morning rise of SAP and DAP was higher in group 1. CONCLUSION: The DMAP data may indicate to some extent the severity of hypertension in patients with CHF, and this probably depends on the ‘stiffness of the vessels’. In elderly patients with CHF with ‘normal stiffness’ of vessels, the parameters of the daily arterial pressure profile were higher than in patients with ‘stiff vessels’. However, the daily range of parameters of the daily arterial pressure profile was greater in the group of patients with ‘stiff vessels’ (group 2).

Experimental evaluation of the out-of-plane behavior of a traditional timber frame with mud and rubble infill wall strengthened by a polypropylene band mesh on one side

The structural integrity of traditional Chinese village residences may be compromised due to inadequate connections between the timber frame and infill walls, coupled with the weak cohesiveness of clay mud. Among the various damage mechanisms resulting from earthquakes, the out-of-plane collapse of infill walls is a recurrent and significant concern. The goal of this research is to investigate the feasibility and effectiveness of a polypropylene (PP) band mesh reinforcement approach for a traditional timber frame with mud and rubble infill walls. The ultimate goals are to prevent out-of-plane collapse, improve the collaborative performance of the structure, reduce seismic vulnerability, and safeguard the architectural heritage of traditional dwellings. With careful consideration of their aesthetics, the study centers on timber frames with mud and rubble infill walls strengthened by a polypropylene (PP) band mesh and cement mortar on one side. A series of experiments were conducted based on out-of-plane cyclic one-way tests of four full-scale specimens. Different loading surfaces and reinforcing PP grid sizes with and without window openings were investigated to characterize the out-of-plane behavior of the reinforced hybrid walls. The damage evolution, failure modes, force–displacement curves, out-of-plane profile characteristics, stiffness, strength, and energy dissipation were described. All the reinforced walls exhibited marked improvements out-of-plane lateral capacity, with enhancements of approximately 120% and 162%, and stiffness increases of approximately 105% and 200%, compared to the unreinforced walls. The minimal out-of-plane displacement observed on the reinforcement side was also accompanied by significant increase in integrity and ductility.

Isotope physics of heat and particle transport with tritium in JET-ILW type-I ELMy H-mode plasmas

As part the DTE2 campaign in the JET tokamak, we conducted a parameter scan in T and D-T complementing existing pulses in H and D. For the different main ion masses, type-I ELMy H-modes at fixed plasma current and magnetic field can have the pedestal pressure varying by a factor of 4 and the total pressure changing from βN=1.0 to 3.0. We investigated the pedestal and core isotope mass dependencies using this extensive data set. The pedestal shows a strong mass dependence on the density, which influences the core due to the strong coupling between both plasma regions. To better understand the causes for the observed isotope mass dependence in the pedestal, we analysed the interplay between heat and particle transport and the edge localised mode (ELM) stability. For this purpose, we developed a dynamic ELM cycle model with basic transport assumptions and a realistic neutral penetration. The temporal evolution and resulting ELM frequency introduce an additional experimental constraint that conventional quasi-stationary transport analysis cannot provide. Our model shows that a mass dependence in the ELM stability or in the transport alone cannot explain the observations. One requires a mass dependence in the ELM stability as well as one in the particle sources. The core confinement time increases with pedestal pressure for all isotope masses due to profile stiffness and electromagnetic turbulence stabilisation. Interestingly, T and D-T plasmas show an improved core confinement time compared to H and D plasmas even for matched pedestal pressures. For T, this improvement is largely due to the unique pedestal composition of higher densities and lower temperatures than H and D. With a reduced gyroBohm factor at lower temperatures, more turbulent drive in the form of steeper gradients is required to transport the same amount of heat. This picture is supported by quasilinear flux-driven modelling using TGLF-SAT2 within Astra. With the experimental boundary condition TGLF-SAT2 predicts the core profiles well for gyroBohm heat fluxes >15 , however, overestimates the heat and particle transport closer to the turbulent threshold.

Effect of polypill therapy on lipid profile and arterial stiffness in patients with dyslipidemia, arterial hypertension and COVID-19 in different age groups

Effect of polypill therapy on lipid profile and arterial stiffness in patients with dyslipidemia, arterial hypertension and COVID-19 in different age groups

On-demand tuning of mechanical stiffness and stability of Kresling origami harnessing its nonrigid folding characteristics

Being adaptive with respect to changing operating conditions and the environment is an imperative demand for advanced engineering structures. In this research, two Kresling origami units are stacked together to form an online and on-demand tunable dual-Kresling origami structure (D-KOS), allowing easy and significant change in the multistability profile and apparent stiffness without redesign. Specifically, by harnessing its nonrigid folding nature together with geometric characteristics, the D-KOS can be programmed to follow distinct paths of its strain energy contour as varying (rotational angle of the top plate of the D-KOS), which can be utilized to explicitly derive different mechanical properties. The D-KOS with identical Kresling origami units can exhibit various symmetric bistable behaviors with different energy barriers via adjusting . Such a structure becomes a monostable system as the tuning variable reaches a critical value. This change in the energy landscape and stability profile gives rise to a change in stiffness at its stable equilibria, which, as a result, creates a wide range of stiffness value one can achieve, including quasi-zero stiffness. Such tuning of does not require redesign of the structure and thus can achieve online and on-demand tailoring. To verify the concept, proof-of-concept prototypes are developed and utilized to validate the D-KOS’s mechanical tunability experimentally. Moreover, the different design parameters of the D-KOS can change its tunability. For example, the D-KOS with nonidentical Kresling origami units can possess even richer stability properties (being asymmetric bistable, symmetric bistable, and monostable) with various energy landscapes. In addition, one can also tailor the range of the adjustable stiffness by changing the design parameters, such as the ratio of the angle between the polygon side and the valley crease of the triangular facets, and the height of the Kresling origami unit.

Blood pressure, arterial stiffness, and cardiovascular risk profiles in 8-12-year-old children following preeclampsia (FINNCARE-study).

The aim was to study if children following preeclampsia (PE) develop alterations in blood pressure (BP) and arterial stiffness already early in life, and how this is associated with gestational, perinatal and child cardiovascular risk profiles. One hundred eighty-two PE (46 early-onset with diagnosis before 34 gestational weeks, and 136 late-onset) and 85 non-PE children were assessed 8-12 years from delivery. Office and 24-h ambulatory BP, body composition, anthropometrics, lipids, glucose, inflammatory markers, and tonometry-derived pulse wave velocity (PWV) and central BPs were assessed. Office BP, central BPs, 24-h systolic BP (SBP) and pulse pressure (PP) were higher in PE compared with non-PE. Early-onset PE children had the highest SBP, SBP-loads, and PP. SBP nondipping during night-time was common among PE. The higher child 24-h mean SBP among PE was explained by maternal SBP at first antenatal visit and prematurity (birth weight or gestational weeks), but child 24-h mean PP remained related with PE and child adiposity after adjustments. Central and peripheral PWVs were elevated in late-onset PE subgroup only and attributed to child age and anthropometrics, child and maternal office SBP at follow-up, but relations with maternal antenatal SBPs and prematurity were not found. There were no differences in body anthropometrics, composition, or blood parameters. PE children develop an adverse BP profile and arterial stiffness early in life. PE-related BP is related with maternal gestational BP and prematurity, whereas arterial stiffness is determined by child characteristics at follow-up. The alterations in BP are pronounced in early-onset PE.Clinical Trial Registration information: https://clinicaltrials.gov/ct2/show/NCT04676295ClinicalTrials.gov Identifier: NCT04676295.

Assessment of hepatic steatosis before and after laparoscopic sleeve gastrectomy

Background Nonalcoholic fatty liver disease (NAFLD) is the cause of the new epidemic of chronic liver disease. Most patients are asymptomatic and accidentally diagnosed by imaging. Unfortunately, NAFLD can progress to inflammation, NASH, fibrosis, cirrhosis, HCC, decompensated cirrhosis, death, and/or liver transplantation might be required. Laparoscopic sleeve gastrectomy (LSG) has positive effects on the comorbidities associated with obesity. FibroScan and controlled attenuation parameter (CAP) can assess NAFLD non-invasively by measuring an area a hundred times larger than a biopsy sample. Aim To assess hepatic steatosis pre and post LSG by laboratory investigations and imaging (fibroscan and CAP). Methods Thirty patients were included in a prospective observational study according to the inclusion criteria. Full medical history, preoperative laboratory investigations and imaging were recorded. All patients underwent LSG and were followed up for 6 months postoperatively. Data were coded and analysed by using (SPSS) version 29. Results LSG was associated with a significant improvement in the controlled attenuation parameter CAP values, stiffness values and accordingly grades of steatosis and fibrosis as well as a highly significant decrease in BMI, and on follow-up fibroscan 6 months postoperatively. There was a significant improvement in total cholesterol, triglycerides, LDL and HDL. Conclusion LSG is associated with a significant improvement in BMI, lipid profile, CAP measurement and liver stiffness measurements which means improvement of steatosis. In morbidly obese candidates of bariatric surgery, Fibroscan with CAP (using the XL probe) was used as a simple non-invasive tool for detecting steatosis and fibrosis.

Prompt core confinement improvement across the L–H transition in DIII-D: Profile stiffness, turbulence dynamics, and isotope effect

We elaborate on the nature of the prompt core confinement improvement observed at the L–H transition in DIII-D, which is a long-standing issue unsolved for more than two decades and can impact future fusion reactor performance. Dynamic transport analysis suggests the essential role of the profile stiffness for understanding the mechanism of the prompt core confinement improvement. Beam emission spectroscopy shows that transport reduction at the core cannot be explained only by the ion scale turbulence density fluctuation suppression. Properties of nonlocal confinement improvement across the L–H transition are experimentally assessed in hydrogen (H) and deuterium (D) plasmas. Prompt core confinement improvement is found to be more rapid in the lighter hydrogen isotope.

Risk factor profile and vascular stiffness in young people living in the North Caucasian Federal District according to remote survey and angiology screening

<h3>ЦЕЛЬ ИССЛЕДОВАНИЯ</h3> Оценить особенности профиля основных факторов риска (ФР) у лиц молодого возраста из регионов Северо-Кавказского федерального округа (СКФО) с помощью дистанционной системы опроса, а также сравнить показатели сосудистой жесткости у представителей этносов, проживающих в регионах указанного округа. <h3>МАТЕРИАЛ И МЕТОДЫ</h3> Обследованы с помощью интернет-опроса для выявления основных ФР (4603 человека) и ангиологического скрининга (277 человек) студенты медицинских вузов, находящихся в регионах СКФО. Инструментальный скрининг включал оценку сердечно-лодыжечного васкулярного индекса (CAVI) с помощью аппарата VaSera VS-1500N (Fukuda Denshi Co., Ltd., Япония). Данный маркер в отличие от скорости распространения пульсовой волны не зависит от уровня артериального давления (АД), действующего на сосудистую стенку в момент регистрации пульсовой волны. Все респонденты разделены на группы сравнения в зависимости от региона проживания, а также в зависимости от этнической принадлежности. В последнем случае представители разных народов распределены по трем группам: 1-я группа — славянские народы, 2-я группа — народы Кавказа, 3-я группа — иные народы. Обработка данных проведена с помощью статистических программ IBM SPSS Statistics 21 и Statistica 10.0 (StatSoft Inc., США). <h3>РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ</h3> Определена частота случаев избыточной массы тела и ожирения, повышенного уровня АД, курения, гиподинамии, а также особенностей питания у лиц молодого возраста из разных вузов СКФО. Интегративный показатель артериальной ригидности CAVI с обеих сторон у лиц группы славянского этноса оказался несколько выше по сравнению с данным показателем у сверстников группы кавказского этноса. Но эта разница не достигала значимого уровня. У молодых людей других национальностей указанный показатель занял промежуточное положение. <h3>ЗАКЛЮЧЕНИЕ</h3> Полученные данные указывают на необходимость совершенствования профилактических мероприятий для молодежи с учетом места проживания и этнической принадлежности. Такой подход способствует реализации более индивидуализированных превентивных программ среди учащейся молодежи, которые соответствуют раннему этапу развития патогенетического сердечно-сосудистого континуума, а поэтому отличается большими шансами коррекции начальных доклинических проявлений артерио- и атеросклероза.

Cold Formed Steel Type C On Beams With Connection Variations

The disadvantages of using cold rolled steel (cold formed steel) include a thin profile and low stiffness of the connecting parts. Stiffness research of various types of joints is needed to study element failure, machine error or connection failure which causes the collapse of cold rolled steel structures. Analysis is needed for cantilever structures, because the maximum deflection that occurs in cantilever structures is greater than that of simply supported beam structures. The shape and type of cold rolled steel joints greatly affect the stiffness and stability of cold rolled steel structures so that the strength of several types of joints must be studied. The purpose of this study was to analyze the stiffness of the test results under the influence of bending loads on each type of cold rolled steel beam-column connection. Cold steel C channel profile with a thickness of 0.75 mm is used as the object in this study. The beam-column structure is assembled with various kinds of connections, including direct screw connections, screw-gusset plates, screw-angle plates, and screw-angle plate-gusset plates. This research shows addition of the elbow plate increases the strength of the test object by means of a screw connection and gusset plate to the load. However, the results of the maximum load in the experiment still have not reached the maximum load of the analysis results. In the screw connection the damage that occurs is tearing in the connecting plate (tear out), in the gusset plate connection the damage that occurs is the collapse of the gusset plate, in the screw-angled plate connection there are 2 damages, where the damage starts with a tear in the connecting plate ( tear out) and followed by damage to the screw that is damaged (pull out).

Experimental evaluation of avalanche type of electron heat transport in magnetic confinement plasmas

Turbulent transport is undoubtedly important in magnetic confinement plasmas. It has been reported that a lot of transport dynamics are not satisfying the local diffusive models. Here, we report the quantitative measurement of electron heat flux associated with ballistic propagating long-range transport events, which is considered to be a component of avalanches. In addition, we show the first observations of the substantial impact of avalanche-driven transport on profile resilience (or profile stiffness) observed in JT-60U. We found that, in the channel of the electron heat flux, the ratio between the increment of the avalanche-driven component to that of the total plasma heating becomes dominant (∼80%) in the case of the high-heating limit. This suggests a possible role for avalanche-driven transport to induce profile resilience, which has been evidenced by flux-driven simulations.

Characteristics of electron temperature profile stiffness in electron-heated plasmas on EAST

A very high core electron temperature (T e0 ∼ 10 keV) plasma has been established and stably sustained by applying both lower hybrid wave (LHW) and on-axis electron cyclotron resonance heating (ECRH) in the Experimental Advanced Superconducting Tokamak (EAST). In this work, power balance analysis shows that the increase of ECRH power can increase the normalized T e gradient significantly at the plasma core region (ρ < 0.6), but does not change the T e profile stiffness in the low-density L-mode plasmas. This has been considered to be due to a strong synergistic effect between ECRH and LHW. Furthermore, three distinguishable stages characterized by different T e profile stiffnesses can be identified from the density ramp-up in the electron-heated plasma on EAST. A stronger T e profile stiffness at ρ = 0.3 has been observed in the Stage-II, where the LHW power deposition gradually moves away from the plasma core region, following the electron density increases. Furthermore, the formation of an internal plasma density transport barrier inside ρ ∼ 0.6, accompanied by a sudden drop in core T e and a rise in both core plasma density and ion temperature, has been observed for the first time during the transition from the Stage-II to the Stage-III when the central line-averaged plasma density reaches a threshold of 2.2 × 1019 m−3. This finding strongly affects further development of high-performance gas-fueled electron-heated plasma scenarios in EAST and suggests an advanced operational regime with a wide internal plasma density transport barrier.

Arterial stiffness in hypertensive patients with peripheral artery disease

Objective. To identify features of arterial stiffness, to establish relationships with indicators of the daily blood pressure profile and peripheral artery disease in patients with hypertension (HTN) in combination with subclinical and manifested atherosclerotic lesions of the arteries of the lower extremities. Design and methods. 120 patients were divided into 3 groups: group 1-46 patients with HTN and clinically manifested AALE, group 2-39 patients with HTN and asymptomatic AALE, group 3-35 HTN patients without AALE. All patients underwent general clinical laboratory and instrumental research methods, including 24-hour blood pressure ambulatory monitoring (24h-ABPM) with the assessment of 24-hour blood pressure profile and arterial stiffness parameters, ultrasonic triplex scanning (USTS) of the arteries of the lower extremities. Statistical data processing was carried out using Microsoft Office Excel 16 (2015, Microsoft, USA), Statistica 10.0 (StatSoft, USA), IBM SPSS Statistica 26.0 (IBM, USA). Results. Higher values of pulse wave velocity (PWVao), augmentation index (AIx) and ambulatory arterial stiffness index (AASI) were found in the 1st group in comparison to the 2nd and 3rd groups (p &lt; 0,05). Lower reflected wave transit time (RWTT) (119,5 [112;127] ms) was found in the 1st group (128 [122;132], p = 0,001 and 126 [121;129] ms, p = 0,03 in the 2nd and and 3rd groups, respectively) groups. The maximum rate of blood pressure increase (dP/dtmax) in patients of the 1st (550 [466;666] mm Hg/s) and 2nd (634 [511;695] mm Hg/s) groups was significantly lower than in patients of the 3rd group (655 [526;806] mm Hg/s, p &lt; 0,05). A direct correlation was found between AASI values and SBP (r = 0,291, p = 0,049) and its variability (r = 0,301, p = 0,042), AASI and PBP (r = 0,518, p &lt; 0,001), its variability (r = 0,596, r &lt; 0,001) in group 1, as well as AASI and PBP (r = 0,514, p &lt; 0,001) and PBP variability (r = 0,632, p &lt; 0,001) in group 2. A correlation between AIx and the degree of stenosis (%) of the arteries of the lower extremities was found in patients with AH and AALE of varying severity (r = 0,310, p = 0,004). Conclusions. In patients with subclinical course of AALE, lower values of dP/dtmax in comparison with HTN patients without AALE indicate an increase in arterial stiffness at the initial stages of peripheral atherosclerosis. Clinically manifested atherosclerotic lesions of the arteries of the lower extremities in HTN patients are associated with a more pronounced increase in arterial stiffness, which contributes to a higher cardiovascular risk.

Recent developments in manufacturing, mechanics, and design optimization of variable stiffness composites

The functional advantages of tailored stiffness, often seen in nature, are also utilized in composite structures. Advancements in the multiaxis tow placement and automated fiber placement (AFP) machines led to the development of variable angle tow (VAT) composites, also referred further as variable stiffness composites (VSC). These composites are shown to effectively enhance the stress distribution and buckling load capacity of structures with greater flexibility on the design space. This review systematically presents the status of recent research on the topic of VSCs. Various manufacturing techniques of VSC are discussed; constraints and the defects associated with the manufacturing processes are enlisted. The review highlights the optimization studies based on the fiber profile and macro-scale stiffness invariants. Several studies existing in the domain of buckling, vibration, and aeroelastic tailoring of angle tow composites are summarized to connect the important aspects of analysis and present a holistic approach for future studies in this area.

Scale effect in the evaluation of the fire resistance of glazed partitions

Fire-resistance testing procedures for glazed partitions used in Europe determine the minimum dimensions of the test items (2.8 × 3.0 m, width × height in the furnace opening lumen). Tests on minimum-sized items enable the evaluation of the fire resistance of slightly larger components. Nonetheless, they do not address the real problem of using fire-resistant glazed partitions, whose heights significantly exceed the dimensions of partitions verified in tests. This study resulted in the development of a model based on testing minimum-sized items, enabling the fire resistance evaluation of aluminium glazed partitions that are much higher than the test items. A typical scale effect should be expected in this situation, resulting from the difference in the dimensions of the test sample and the actual glass partition. The model was developed based on the results of eight tests on glazed partitions. The tests performed showed that there is a relationship between the profile stiffness in a glazed partition's mullion and the mullion's deflection during a fire-resistance test. Moreover, it was observed that if a low partition maintains its fire integrity and insulation, identical behaviour can be expected of higher partitions in specific conditions. These phenomena aimed to develop an algorithm that enables the evaluation of the maximum acceptable height of an aluminium glazed partition for which the fire resistance is maintained.