СПЕКТРЫ DLTS КРЕМНИЕВЫХ ДИОДОВ С p+—n–ПЕРЕХОДОМ, ОБЛУЧЕННЫХ ВЫСОКОЭНЕРГЕТИЧЕСКИМИ ИОНАМИ КРИПТОНА

p+-n-Diodes have been studied. The diodes were manufactured on wafers (thickness 460 μm, (111) plane) of uniformly phosphorus doped float–zone–grown single–crystal silicon. The resistivity of silicon was 90 Ohm · cm and the phosphorus concentration was 5 · 1013 cm–3. The diodes were irradiated with 250 MeV krypton ions. The irradiation fluence was 108 cm–2. Deep–level transient spectroscopy (DLTS) was used to examine the defects induced by high energy krypton ion implantation. The DLTS spectra were recorded at a frequency of 1 MHz in the 78—290 K temperature range. The capacity–voltage characteristics have been measured at a reverse bias voltage from 0 to –19 V at a frequency of 1 MHz. We show that the main irradiation–induced defects are A–centers and divacancies. The behavior of DLTS spectra in the 150—260 K temperature range depends essentially on the emission voltage Ue. The variation of Ue allows us to separate the contributions of different defects into the DLTS spectrum in the 150—260 K temperature range. We show that, in addition to A–centers and divacancies, irradiation produces multivacancy complexes with the energy level Et = Ec – (0.5 ± 0.02) eV and an electron capture cross section of ~4 · 10–13 cm2.Исследованы p+—n-диоды. Диоды изготовлены на пластинах однородно легированного фосфором монокристаллического кремния (толщина 460 мкм, плоскость (111)), выращенного методом бестигельной зонной плавки. Удельное сопротивление кремния — 90 Ом × см, концентрация фосфора — 5 × 1013 см−3. Диоды подвергнуты облучению ионами криптона с энергией 250 МэВ. Флюенс облучения — 108 см−2. Радиационные дефекты, вводимые высокоэнергетической имплантацией ионов криптона, исследованы с помощью нестационарной спектроскопии глубоких уровней (DLTS — Deep−level transient spectroscopy). Спектры DLTS регистрировали на частоте 1 МГц в интервале температур 78—290 К. Вольт-фарадные характеристики измерены при напряжении обратного смещения от 0 до – 19 В на частоте 1 МГц. Показано, что основными радиационными дефектами являются А−центры и дивакансии. Установлено, что вид спектров DLTS в интервале температур 150—260 K существенно зависит от напряжения эмиссии Ue. Варьирование Ue в ходе эксперимента позволило разделить вклады от различных дефектов в спектр DLTS в интервале температур 150—260 К. Показано, что, помимо А−центров и дивакансий, при облучении формируются многовакансионные комплексы с энергетическим уровнем Et = Ec -(0,50 ± 0,02) эВ и сечением захвата электронов ~ 4 × 10−13 см2

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

A simplified calculation method of electric linear actuators for single-axis sun tracker

At present, the use of small roof-mounted photovoltaic systems is increasingly popular, so the development of a sun tracker to increase the efficiency of the photovoltaic system is essential. In this paper, we give the size analysis of a linear actuator and also its selection method for a single-axis tracker. In addition, we also provide the analysis of the power and energy of the linear actuator and its controller on a typical sunny day

Applying the SIMPLE Crop Model to Assess Soybean (<i>Glicine max.</i> (L.) Merr.) Biomass and Yield in Tropical Climate Variation

Soybean Glicine max. (L.) Merr. is one of the most major food crops. In some areas, its responses to different climates have not been well studied, particularly in tropical countries where other crops are more dominant. Accordingly, we adopted the SIMPLE crop model to investigate the responses of soybeans to the climate. We conducted two experiments on crop growth in the Summer–Autumn season of 2020, and Winter–Spring 2021 in the Hoa Binh Commune, in the Mekong Delta, Vietnam, which is an area that is vulnerable to climate change impacts, to obtain data for our model input and assessment. The assessment was concerned with the effects of climate variables (temperature and CO2) on soybean biomass and yield. The results indicated that the SIMPLE model performed well in simulating soybean yields, with an RRMSE of 9–10% overall. The drought stress results showed a negative impact on the growth and development of soybeans, although drought stress due to less rainfall seemed more serious in Spring–Winter 2021 than in Summer–Autumn 2020. This study figured out the trend that higher temperatures can shorten biomass development and lead to yield reduction. In addition, soybeans grown under high CO2 concentrations of 600 ppm gave a higher biomass and a greater yield than in the case with 350 ppm. In conclusion, climate variance can affect the soybean yield, which can be well investigated using the SIMPLE model

Optimization of the calcination and two-step sintering temperatures of (K0.48Na0.48Li0.04)(Nb0.95Sb0.05)O3 ceramics

Lead-free (K _0.48 Na _0.48 Li _0.04 )(Nb _0.95 Sb _0.05 )O _3 (KNLNS) ceramics have been successfully optimized for the calcination and two-step sintering temperatures. The experimental results reveal that the KNLNS powder calcined at 850 or 900 °C presented a pure perovskite phase with an orthorhombic phase. The particle size was in the range of 0.1–0.4 μ m. The two-step sintering temperature (range: 950 to 1100 °C) significantly affects the structure, microstructure, and electrical properties of KNLNS ceramics. The presence of a pure perovskite phase with good crystallization is observed in all samples. The microstructure was researched by varying the two-step sintering temperature to obtain a dense microstructure and a clear grain boundary in order to optimize their piezoelectric properties. The best electrical properties of KNLNS ceramics were recorded at the optimized temperature of 1050 °C (density ( ρ ): 4,35 g cm ^−3 ; electromechanical coupling factor ( k _p ): 0.33, k _t : 0.35; dielectric constant ( ε _r ): 849; dielectric loss (tan δ ): 0.073; maximum dielectric constant ( ε _max at T _C ): 6659; piezoelectric constant ( d _33 ): 195 pC N ^−1 ; remanent polarization ( P _r ): 16.1 μ C cm ^−2 ; energy storage density ( W _rec ): 0.36 J cm ^−3 ; energy storage efficiency ( η ): 48.1%; t _2 = 4 h), proving the efficacy of the two-step sintering technique

DLTS spectra of silicon diodes with p+-n-junction irradiated with high energy krypton ions

p+-n-Diodes have been studied. The diodes were manufactured on wafers (thickness 460 μm, (111) plane) of uniformly phosphorus doped float-zone-grown single-crystal silicon. The resistivity of silicon was 90 Ω cm and the phosphorus concentration was 5×1013 cm−3. The diodes were irradiated with 250 MeV krypton ions. The irradiation fluence was 108 cm−2. Deep-level transient spectroscopy (DLTS) was used to examine the defects induced by high energy krypton ion implantation. The DLTS spectra were recorded at a frequency of 1 MHz in the 78–290 K temperature range. The capacity-voltage characteristics have been measured at a reverse bias voltage from 0 to −19 V at a frequency of 1 MHz. We show that the main irradiation-induced defects are A-centers and divacancies. The behavior of DLTS spectra in the 150–260 K temperature range depends essentially on the emission voltage Ue. The variation of Ue allows us to separate the contributions of different defects into the DLTS spectrum in the 150–260 K temperature range. We show that, in addition to A-centers and divacancies, irradiation produces multivacancy complexes with the energy level Et = Ec−(0.5±0.02) eV and an electron capture cross section of ~4×10–13 cm2

The Performance of a Modified Glasgow Blatchford Score in Predicting Clinical Interventions in Patients with Acute Nonvariceal Upper Gastrointestinal Bleeding: A Vietnamese Prospective Multicenter Cohort Study

BACKGROUND/AIMS: To compare the performance of a modified Glasgow Blatchford score (mGBS) to the Glasgow Blatchford score (GBS) and the pre-endoscopic Rockall score (RS) in predicting clinical interventions in Vietnamese patients with acute nonvariceal upper gastrointestinal bleeding (AN-VUGIB). METHODS: A prospective multicenter cohort study was conducted in five tertiary hospitals from May 2013 to February 2014. The mGBS, GBS, and pre-endoscopic RS scores were prospectively calculated for all patients. The accuracy of mGBS was compared with that of GBS and pre-endoscopic RS using area under the receiver operating characteristic curve (AUC). Clinical interventions were defined as blood transfusions, endoscopic or radiological intervention, or surgery. RESULTS: There were 395 patients including 128 (32.4%) needing endoscopic treatment, 117 (29.6%) requiring blood transfusion and two (0.5%) needing surgery. In predicting the need for clinical intervention, the mGBS (AUC, 0.707) performed as well as the GBS (AUC, 0.708; p=0.87) and outperformed the pre-endoscopic RS (AUC, 0.594; p<0.001). However, none of these scores effectively excluded the need for endoscopic intervention at a threshold of 0. CONCLUSIONS: mGBS performed as well as GBS and better than pre-endoscopic RS for predicting clinical interventions in Vietnamese patients with ANVUGIB

Effect of the Optimize Heart Failure Care Program on clinical and patient outcomes – The pilot implementation in Vietnam

Background: The Ho-Chi-Minh-city Heart Institute in Vietnam took part in the Optimize Heart Failure (OHF) Care Program, designed to improve outcomes following heart failure (HF) hospitalization by increasing patient awareness and optimizing HF treatment. Methods: HF patients hospitalized with left ventricular ejection-fraction (LVEF) <50% were included. Patients received guideline-recommended HF treatment and education. Clinical signs, treatments and outcomes were assessed at admission, discharge, 2 and 6 months (M2, M6). Patients' knowledge and practice were assessed at M6 by telephone survey. Results: 257 patients were included. Between admission and M2 and M6, heart rate decreased significantly, and clinical symptoms improved significantly. LVEF increased significantly from admission to M6. 85% to 99% of patients received education. At M6, 45% to 78% of patients acquired knowledge and adhered to practice regarding diet, exercise, weight control, and detection of worsening symptoms. High use of renin-angiotensin-aldosterone-system inhibitors (91%), mineralocorticoid-receptor-antagonists (77%) and diuretics (85%) was noted at discharge. Beta-blocker and ivabradine use was less frequent at discharge but increased significantly at M6 (from 33% to 51% and from 9% to 20%, respectively, p < 0.001). There were no in-hospital deaths. Readmission rates at 30 and 60 days after discharge were 8.3% and 12.5%, respectively. Mortality rates at 30 days, 60 days and 6 months were 1.2%, 2.5% and 6.4%, respectively. Conclusions: The OHF Care Program could be implemented in Vietnam without difficulty and was associated with high usage of guideline-recommended drug therapy. Although education was delivered, patient knowledge and practice could be further improved at M6 after discharge. Keywords: Heart failure, Optimize, Education, Knowledge, Mortality, Readmissio

Twelve-Month Outcomes of the AFFINITY Trial of Fluoxetine for Functional Recovery After Acute Stroke: AFFINITY Trial Steering Committee on Behalf of the AFFINITY Trial Collaboration

Background and Purpose: The AFFINITY trial (Assessment of Fluoxetine in Stroke Recovery) reported that oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and seizures. After trial medication was ceased at 6 months, survivors were followed to 12 months post-randomization. This preplanned secondary analysis aimed to determine any sustained or delayed effects of fluoxetine at 12 months post-randomization. Methods: AFFINITY was a randomized, parallel-group, double-blind, placebo-controlled trial in adults (n=1280) with a clinical diagnosis of stroke in the previous 2 to 15 days and persisting neurological deficit who were recruited at 43 hospital stroke units in Australia (n=29), New Zealand (4), and Vietnam (10) between 2013 and 2019. Participants were randomized to oral fluoxetine 20 mg once daily (n=642) or matching placebo (n=638) for 6 months and followed until 12 months after randomization. The primary outcome was function, measured by the modified Rankin Scale, at 6 months. Secondary outcomes for these analyses included measures of the modified Rankin Scale, mood, cognition, overall health status, fatigue, health-related quality of life, and safety at 12 months. Results: Adherence to trial medication was for a mean 167 (SD 48) days and similar between randomized groups. At 12 months, the distribution of modified Rankin Scale categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio, 0.93 [95% CI, 0.76–1.14]; P =0.46). Compared with placebo, patients allocated fluoxetine had fewer recurrent ischemic strokes (14 [2.18%] versus 29 [4.55%]; P =0.02), and no longer had significantly more falls (27 [4.21%] versus 15 [2.35%]; P =0.08), bone fractures (23 [3.58%] versus 11 [1.72%]; P =0.05), or seizures (11 [1.71%] versus 8 [1.25%]; P =0.64) at 12 months. Conclusions: Fluoxetine 20 mg daily for 6 months after acute stroke had no delayed or sustained effect on functional outcome, falls, bone fractures, or seizures at 12 months poststroke. The lower rate of recurrent ischemic stroke in the fluoxetine group is most likely a chance finding. REGISTRATION: URL: http://www.anzctr.org.au/ ; Unique identifier: ACTRN12611000774921