Modeling AlGaN p-i-n photodiodes

Ternary AlGaN alloys with a band gap of 3.4 to 6.2 eV are very promising for photodetectors in the UV wavelength range. Using the COMSOL MULTIPHYSICS software based on AlGaN, a p-i-n photodiode model was developed, including its I–V characteristic, spectral sensitivity of the received radiation, absorption coefficient as a function of the aluminum fraction and the depletion layer thickness. To calculate the process of interaction of a semiconductor with EM radiation, we used a model based on the use of an element of the transition matrix through the carrier lifetime during spontaneous recombination. In this case, the peak sensitivity of the photodiode is from 0.08 to 0.18 A/W at wavelengths of 0.2–0.33 µm. This is in line with experimental results taken from the relevant literature.Ternary AlGaN alloys with a band gap of 3.4 to 6.2 eV are very promising for photodetectors in the UV wavelength range. Using the COMSOL MULTIPHYSICS software based on AlGaN, a p-i-n photodiode model was developed, including its I–V characteristic, spectral sensitivity of the received radiation, absorption coefficient as a function of the aluminum fraction and the depletion layer thickness. To calculate the process of interaction of a semiconductor with EM radiation, we used a model based on the use of an element of the transition matrix through the carrier lifetime during spontaneous recombination. In this case, the peak sensitivity of the photodiode is from 0.08 to 0.18 A/W at wavelengths of 0.2–0.33 µm. This is in line with experimental results taken from the relevant literature

The Investigation of the Inhabited Landscapes for the Optimization of the District Planning of Volyn’ and for the Conditions of the Constant Development of the Region

Розглядається роль селитебних ландшафтів у формуванні сталого розвитку Волинської області, оптимізації районного планування. Виокремлено основні заходи для забезпечення сталого розвитку регіону. It is investigated the role of the inhabited landscapes in the sphere of the forming of the constant development of Volyn’ region and the optimization of the regional planning. It was selected the main points for the providing of the constant development of the region

Modeling AlGaN p-i-n photodiodes

Ternary AlGaN alloys with a band gap of 3.4 to 6.2 eV are very promising for photodetectors in the UV wavelength range. Using the COMSOL MULTIPHYSICS software based on AlGaN, a p-i-n photodiode model was developed, including its I–V characteristic, spectral sensitivity of the received radiation, absorption coefficient as a function of the aluminum fraction and the depletion layer thickness. To calculate the process of interaction of a semiconductor with EM radiation, we used a model based on the use of an element of the transition matrix through the carrier lifetime during spontaneous recombination. In this case, the peak sensitivity of the photodiode is from 0.08 to 0.18 A/W at wavelengths of 0.2–0.33 µm. This is in line with experimental results taken from the relevant literature

The role of bioreductive activation of doxorubicin in cytotoxic activity against leukaemia HL60-sensitive cell line and its multidrug-resistant sublines

Clinical usefulness of doxorubicin (DOX) is limited by the occurrence of multidrug resistance (MDR) associated with the presence of membrane transporters (e.g. P-glycoprotein, MRP1) responsible for the active efflux of drugs out of resistant cells. Doxorubicin is a well-known bioreductive antitumour drug. Its ability to undergo a one-electron reduction by cellular oxidoreductases is related to the formation of an unstable semiquionone radical and followed by the production of reactive oxygen species. There is an increasing body of evidence that the activation of bioreductive drugs could result in the alkylation or crosslinking binding of DNA and lead to the significant increase in the cytotoxic activity against tumour cells. The aim of this study was to examine the role of reductive activation of DOX by the human liver NADPH cytochrome P450 reductase (CPR) in increasing its cytotoxic activity especially in regard to MDR tumour cells. It has been evidenced that, upon CPR catalysis, DOX underwent only the redox cycling (at low NADPH concentration) or a multistage chemical transformation (at high NADPH concentration). It was also found, using superoxide dismutase (SOD), that the first stage undergoing reductive activation according to the mechanism of the redox cycling had the key importance for the metabolic conversion of DOX. In the second part of this work, the ability of DOX to inhibit the growth of human promyelocytic-sensitive leukaemia HL60 cell line as well as its MDR sublines exhibiting two different phenotypes of MDR related to the overexpression of P-glycoprotein (HL60/VINC) or MRP1 (HL60/DOX) was studied in the presence of exogenously added CPR. Our assays showed that the presence of CPR catalysing only the redox cycling of DOX had no effect in increasing its cytotoxicity against sensitive and MDR tumour cells. In contrast, an important increase in cytotoxic activity of DOX after its reductive conversion by CPR was observed against HL60 as well as HL60/VINC and HL60/DOX cells

Financial Incentive Increases CPAP Acceptance in Patients from Low Socioeconomic Background

OBJECTIVE: We explored whether financial incentives have a role in patients' decisions to accept (purchase) a continuous positive airway pressure (CPAP) device in a healthcare system that requires cost sharing. DESIGN: Longitudinal interventional study. PATIENTS: The group receiving financial incentive (n = 137, 50.8±10.6 years, apnea/hypopnea index (AHI) 38.7±19.9 events/hr) and the control group (n = 121, 50.9±10.3 years, AHI 39.9±22) underwent attendant titration and a two-week adaptation to CPAP. Patients in the control group had a co-payment of $330-660; the financial incentive group paid a subsidized price of$55. RESULTS: CPAP acceptance was 43% greater (p = 0.02) in the financial incentive group. CPAP acceptance among the low socioeconomic strata (n = 113) (adjusting for age, gender, BMI, tobacco smoking) was enhanced by financial incentive (OR, 95% CI) (3.43, 1.09-10.85), age (1.1, 1.03-1.17), AHI (>30 vs. <30) (4.87, 1.56-15.2), and by family/friends who had positive experience with CPAP (4.29, 1.05-17.51). Among average/high-income patients (n = 145) CPAP acceptance was affected by AHI (>30 vs. <30) (3.16, 1.14-8.75), living with a partner (8.82, 1.03-75.8) but not by the financial incentive. At one-year follow-up CPAP adherence was similar in the financial incentive and control groups, 35% and 39%, respectively (p = 0.82). Adherence rate was sensitive to education (+yr) (1.28, 1.06-1.55) and AHI (>30 vs. <30) (5.25, 1.34-18.5). CONCLUSIONS: Minimizing cost sharing reduces a barrier for CPAP acceptance among low socioeconomic status patients. Thus, financial incentive should be applied as a policy to encourage CPAP treatment, especially among low socioeconomic strata patients

Urinary Extracellular Domain of Neurotrophin Receptor p75 as a Biomarker for Amyotrophic Lateral Sclerosis in a Chinese cohort

To comprehensively assess whether p75ECD in urine could be a candidate biomarker for ALS evaluation. Urine samples were collected from 101 ALS patients, 108 patients with other neurological disease (OND) and 97 healthy controls. 61 ALS patients were followed up with clinical data including ALSFRS-r every 6 to 12 months, 23 ALS patients died and 17 ALS patients lost touch during follow up period. Enzyme-linked immunoassay was employed to determine urine p75ECD concentration. The ALSFRS-r was employed to assess the severity of ALS. The concentration of p75ECD in ALS was significantly higher than that of OND and CTRL (p < 0.001). Additionally, urine p75ECD concentrations in ALS-definite grade patients were significantly higher than that in ALS-probable grade and ALS-possible grade patients (p < 0.001). Higher urine p75ECD concentrations were correlated with increased clinical stage (p = 0.0309); urine p75ECD concentrations and ALSFRS-r were negatively correlated (p = 0.022); and urine p75ECD concentration in the fast-progressing ALS group was significantly higher than that in slow-progression (p = 0.0026). Our finding indicates that urine p75ECD concentration provides additional evidence for patients with clinically suspected ALS, and can be employed to evaluate ALS-severity

Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

Оценка фармакологической безопасности нового дипептидного миметика 2-й петли BDNF при совместном введении с этанолом

To assess the pharmacological safety of the dipeptide mimetic of the 2nd loop of BDNF (compound GTS-201) when co-administered with ethanol, its effect on the alteration in motor activity induced by ethanol during acute and subchronic administration in mice C57Bl/6 and DBA/2 was studied. It was found that GTS-201 at a dose of 5.0 mg / kg, i.p., without affecting spontaneous motor activity per se, after a preliminary acute administration prevented the development of a sedative reaction caused by ethanol (2.0 g/ kg, i.p.) in C57Bl/6 mice. After subchronic administration, GTS-201 is devoid of psychostimulant effect and impact on the formation of ethanol-induced behavioral sensitization in DBA/2 mice. The data obtained indicate the absence of a psychostimulant component and synergism in the pharmacological profile of GTS-201 when used with ethanol at low dose.Для оценки фармакологической безопасности дипептидного миметика 2-й петли BDNF (соединение ГТС-201) при совместном введении с этанолом изучено его влияние на изменение двигательной активности, вызываемое этанолом при остром и субхроническом введении у мышей C57Bl/6 и DBA/2. Установлено, что ГТС-201 в дозе 5,0 мг/кг, в/б, не влияя на спонтанную двигательную активность per se, при предварительном однократном введении препятствовал развитию седативной реакции, вызываемой этанолом (2,0 г/кг, в/б) у мышей C57Bl/6. При субхроническом введении ГТС-201 лишён психостимулирующего действия и влияния на формирование поведенческой сенсибилизации, индуцированной этанолом, у мышей DBA/2. Полученные данные свидетельствуют об отсутствии в фармакологическом профиле ГТС-201 психостимулирующего компонента и синергизма при использовании с этанолом в низкой дозе

Скрининговое изучение эффектов миметиков фактора роста нервов и мозгового нейротрофического фактора на экспериментальной модели депрессии

At the Zakusov Institute of Pharmacology designed and synthesized dimeric dipeptide mimetics of the 1st (GK-6) and 4th (GK-2) nerve growth factor loops, 1st (GSB-214), 2nd (GTS-201) and 4th (GSB -106, GSB-106Ac) brain-derived neurotrophic factor loops. Antidepressant activity of GSB-106 has already been established by oral and intraperitoneal administration in 0.1-5.0 mg/kg doses. Newly synthesized mimetics were studied in comparison with GSB-106 for antidepressant-like activity in the forced swim test on male Balb/c mice with a single intraperitoneal administration. It was found that only mimetic of the fourth brain-derived neurotrophic factor loop GSB-106Ac, varied from GSB-106 by replace monosuccinyl fragment to acetyl, has antidepressant activity in doses of 1.0 mg / kg and 5.0 mg / kg.В НИИ фармакологии имени В.В. Закусова сконструированы и синтезированы димерные дипептидные миметики 1-й (ГК-6) и 4-й (ГК-2) петель фактора роста нервов, 1-й (ГСБ-214), 2-й (ГТС-201) и 4-й (ГСБ-106, ГСБ-106Ас) петель мозгового нейротрофического фактора. Для ГСБ-106 ранее установлена антидепрессивноподобная активность в дозах 0,1-5,0 мг/кг при введении внутрь и внутрибрюшинно. Вновь синтезированные миметики изучены в сравнении с ГСБ-106 на наличие антидепрессивноподобной активности в тесте вынужденного плавания на мышах-самцах Balb/c при однократном внутрибрюшинном введении. Установлено, что только миметик 4-й петли BDNF ГСБ-106Ас, отличающийся от ГСБ-106 заменой моно-сукцинильного фрагмента на ацетильный, обладал антидепрессивноподобным действием в дозах 1,0 мг/кг и 5,0 мг/кг

Сравнение нейропротекторных свойств дипептидных ми-метиков 1-й, 2-й и 4-й петель мозгового нейротрофического фактора на модели окислительного стресса in vitro

Resume. The purpose of this study was to compare neuroprotective properties of the dimeric dipeptide mimetics of the 1st, 2nd and 4th Loops of BDNF - GSB-214 (heptamethylenediamide bis-monosuccinyl-methionyl-serine), GTS-201 (hexamethylenediamide bis-hexanoyl-seryl-lysine) and GSB-106 (hexamethylenediamide bis-monosuccinyl-seryl-lysine) in the HT-22 hippocampal cells in conditions of oxidative stress. It has been established that the mimetic of the 4th loop of BDNF shows a neuroprotective effect in lower concentrations compared to mimetics based on the 1st and 2nd loops when applied 24 hours before and immediately after the damages.Цель настоящей работы состояла в сравнении нейропротекторных свойств димерных дипептидных миметиков 1-й, 2-й и 4-й петель BDNF - ГСБ-214 (гептаметилендиамид бис-моносукцинил-метионил-серина), ГТС-201 (гексаметилендиамид бис-гексаноил-серил-лизина) и ГСБ-106 (гексаметилендиамид бис-моносукцинил-серил-лизина) на гиппокампальных клетках линии HT-22 в условиях окислительного стресса. Установлено, что миметик 4-й петли BDNF проявляет нейропротекторный эффект в более низких концентрациях по сравнению с миметиками на основе 1-й и 2-й петель, как при внесении за 24 часа до повреждения, так и сразу после деструктивного воздействия