Reconfigurable Low-Voltage Hexagonal Boron Nitride Nonvolatile Switches for Millimeter-Wave Wireless Communications.

Recently, nonvolatile resistive switching memory effects have been actively studied in two-dimensional (2D) transition metal dichalcogenides and boron nitrides to advance future memory and neuromorphic computing applications. Here, we report on radiofrequency (RF) switches utilizing hexagonal boron nitride (h-BN) memristors that afford operation in the millimeter-wave (mmWave) range. Notably, silver (Ag) electrodes to h-BN offer outstanding nonvolatile bipolar resistive switching characteristics with a high ON/OFF switching ratio of 10 and low switching voltage below 0.

Autoimmune Rheumatic Diseases and Vascular Function: The Concept of Autoimmune Atherosclerosis.

Autoimmune rheumatic diseases (AIRDs) with unknown etiology are increasing in incidence and prevalence. Up to 5% of the population is affected. AIRDs include rheumatoid arthritis, system lupus erythematosus, systemic sclerosis, and Sjögren's syndrome.

A Pilot Study: Hypertension, Endothelial Dysfunction and Retinal Microvasculature in Rheumatic Autoimmune Diseases.

Background: The etiology of autoimmune rheumatic diseases is unknown. Endothelial dysfunction and premature atherosclerosis are commonly seen in these patients. Atherosclerosis is considered one of the main causes of cardiovascular diseases.

Fluid Shifts Induced by Physical Therapy in Lower Limb Lymphedema Patients.

Complete decongestive therapy (CDT), a physical therapy including manual lymphatic drainage (MLD) and compression bandaging, is aimed at mobilizing fluid and reducing limb volume in lymphedema patients. Details of fluid shifts occurring in response to CDT are currently not well studied. Therefore, we investigated fluid shifts before, during and after CDT.

Coagulation Changes during Central Hypovolemia across Seasons.

Lower body negative pressure (LBNP) application simulates hemorrhage. We investigated how seasons affect coagulation values at rest and during LBNP. Healthy participants were tested in cold (November-April) and warm (May-October) months.

Menstrual Phase Affects Coagulation and Hematological Parameters during Central Hypovolemia.

Background: It has been reported that women have a higher number of heart attacks in the "follicular phase" of the menstrual cycle. We, therefore, tested the hypothesis that women in the follicular phase exhibit higher coagulability. As lower body negative pressure (LBNP) has been used previously to assess coagulation changes in whole blood (WB) samples in men and women, effects of menstrual phase on coagulation was assessed during LBNP.

Psychophysiological concomitants of burnout: Evidence for different subtypes.

Background: There is evidence that chronic stress and emotional exhaustion are related to physiological dysregulations, which could negatively impact physical and mental health. This study aimed to identify the specific physiological clusters which are most reliable and prominently associated with burnout. Emphasis was placed on variables of the autonomic nervous system and hypothalamic-pituitary-adrenal axis.

Galanin and Adrenomedullin Plasma Responses During Artificial Gravity on a Human Short-Arm Centrifuge.

Galanin and adrenomedullin plasma responses to head-up tilt and lower body negative pressure have been studied previously. However, to what extent short-arm human centrifugation (SAHC) affects these responses is not known. In this study, we assessed how the application of variable gradients of accelerations ( ) via shifting of the rotation axis during centrifugation affects selected hormonal responses.

Comparison between men and women of volume regulating hormones and aquaporin-2 excretion following graded central hypovolemia.

Central hypovolemia induced by orthostatic loading causes reno-vascular changes that can lead to orthostatic intolerance. In this study, we investigated volume regulating hormonal responses and reno-vascular changes in male and female subjects as they underwent central hypovolemia, induced by graded lower body negative pressure (LBNP). Aquaporin-2 (AQP2) excretion was measured as a biomarker for the renal system response to vasopressin.

Heart rate variability and baroreceptor reflex sensitivity in early- versus late-onset preeclampsia.

Objective: To determine whether there are differences in autonomic nervous system function in early- versus late-onset preeclampsia.

Methods: Matched case-control study. Cases were defined as singleton pregnancies with preeclampsia at < 34+0 weeks of gestation (early-onset preeclampsia) and ≥ 34+0 weeks of gestation (late-onset preeclampsia).

Systemic vascular resistance and endogenous inhibitors of nitric oxide synthesis in early- compared to late-onset preeclampsia: preliminary findings.

Objective: To examine systemic vascular resistance index (SVRI), asymmetric (ADMA) and symmetric dimethylarginine (SDMA) levels in preeclampsia at different gestations.

Methods: Twenty-four preeclamptic patients (14 at ≥ 34 weeks') and 72 matched healthy controls were included. SVRI was calculated from impedance cardiography measurements.

Volume regulation and renal function at high altitude across gender.

Aims: We investigated changes in volume regulating hormones and renal function at high altitudes and across gender.

Methodology: Included in this study were 28 subjects (n = 20 males; n = 8 females. ages: 19 - 65 yrs), who ascended to a height of 3440m (HA1), on the 3rd day and to 5050m (HA2), on the 14th day.

Effect of orthostasis on endothelial function: a gender comparative study.

As the vascular endothelium has multiple functions, including regulation of vascular tone, it may play a role in the pathophysiology of orthostatic intolerance. We investigated the effect of orthostasis on endothelial function using EndoPAT®, a non-invasive and user-independent method, and across gender. As sex steroid hormones are known to affect endothelial function, this study examined the potential effect of these hormones on the endothelial response to orthostasis by including females at different phases of the menstrual cycle (follicular and luteal-where the hormone balance differs), and females taking an oral contraceptive.

Phase synchronization of hemodynamic variables at rest and after deep breathing measured during the course of pregnancy.

Background: The autonomic nervous system plays a central role in the functioning of systems critical for the homeostasis maintenance. However, its role in the cardiovascular adaptation to pregnancy-related demands is poorly understood. We explored the maternal cardiovascular systems throughout pregnancy to quantify pregnancy-related autonomic nervous system adaptations.

Coagulation changes during presyncope and recovery.

Orthostatic stress activates the coagulation system. The extent of coagulation activation with full orthostatic load leading to presyncope is unknown. We examined in 7 healthy males whether presyncope, using a combination of head up tilt (HUT) and lower body negative pressure (LBNP), leads to coagulation changes as well as in the return to baseline during recovery.

Paradoxical clearance of hyaluronan fragments during haemodialysis and haemodiafiltration.

Background: The physiological clearance of hyaluronic acid (HA), a mortality marker in end-stage kidney disease (ESKD) patients, occurs in the liver and in the kidneys and depends on its molecular mass. The aim of this study was to examine the effect of different modes of renal replacement therapy on levels of low- and high-molecular-mass HA (LMWHA and HMWHA, respectively).

Methods: Levels of total plasma HA as well as LMWHA and HMWHA fractions were measured before and after haemodialysis (HD) and haemodiafliltration (HDF) treatments and compared with those in normal controls.

Delaying orthostatic syncope with mental challenge: a pilot study.

At orthostatic vasovagal syncope there appears to be a sudden decline of sympathetic activity. As mental challenge activates the sympathetic system, we hypothesized that doing mental arithmetic in volunteers driven to the end point of their cardiovascular stability may delay the onset of orthostatic syncope. We investigated this in healthy male subjects.

Volume regulating hormone responses to repeated head-up tilt and lower body negative pressure.

Background: We hypothesized the existence of different hormonal response patterns to repeated lower body negative pressure (LBNP) and head-up tilt (HUT) in healthy males. We compared hormonal, cardiovascular and plasma volume changes from rest to stress within- and between-LBNP and HUT applications. Hormones investigated included adrenocorticotropic hormone (ACTH), aldosterone, plasma renin activity (PRA), atrial natriuretic peptide (ANP) and arginine vasopressin (AVP).

Phase synchronization of hemodynamic variables and respiration during mental challenge.

We studied the synchronization of heart rate, blood pressure and respiration in the sympathetic and parasympathetic branches of the autonomic nervous system during a cancellation test of attention and during mental arithmetic tasks. The synchronization was quantified by the index γ, which has been adopted from the analysis of weakly coupled chaotic oscillators. We analyzed in twenty healthy women the continuous signals partitioned in low (LF, 0.

Modulation of plasma adrenomedullin by epinephrine infusion during head up tilt.

We investigated whether head up tilt (HUT) with and without simultaneous epinephrine infusion modulate plasma adrenomedullin. We studied eight healthy male volunteers, using two 5 min 70° HUT trials: control (saline infusion) and intervention (epinephrine infusion, titrated to a dose which increased supine systolic pressure by 20% above resting values). Protocols were randomized and separated by 2 weeks.

Time course of cardiovascular responses induced by mental and orthostatic challenges.

Cardiovascular responses to single stressors diminish over time. Interaction of different stressors influencing hemodynamic variables, indicative of stress-induced reactivity and physiological responses are, however, poorly understood. We investigated time course of mental (using mental arithmetic, MA) and orthostatic (using head up tilt, HUT) challenges induced responses in 16 males.