High-voltage pulse generator based on sequentially charged MMC-SMs operating in a voltage-boost mode

Pulse forming networks and Marx generators are the classical rectangular waveform pulse generators (PGs). They are inflexible and their capacitors must be fully charged to the required voltage from 0V before delivering each high-voltage (HV) pulse. They are only able to generate unipolar pulses; if bipolar pulses are sought another generator fed from a negative supply voltage is added. Recently, several power electronics based PGs have been proposed. This paper presents an HV power electronics based PG, which is based on Half-Bridge Modular Multilevel Converter (HB-MMC) sub-modules (SMs) charged sequentially in a voltage boost mode. Each SM capacitor and main switch form a boost converter with the charging input supply and inductor. As a result, all SM capacitors are charged to a voltage greater than the input. During the discharging process the SM capacitors are connected in series, producing a rectangular HV pulse across the load. The proposed charging method allows a reduction in the converter footprint in comparison with recently proposed MMC sequentially charged PG topologies. Although only rectangular pulse waveforms are sought in this paper, a SM capacitor voltage balance method allows multilevel pulse generation. The viability of the proposed converter is confirmed by MATLAB/Simulink simulation and scaled-down experimentation

BLOOM: A 176B-Parameter Open-Access Multilingual Language Model

Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License

Choroidal metastasis: Clinical aspects at a referral ocular oncology center

Purpose: To report clinical aspects of choroidal metastasis at an ocular oncology referral center Methods: We reviewed the records of all patients with choroidal metastasis referred to an ocular oncology referral center over a 10-year period retrospectively. The study was performed to identify and analyze clinical presentations and features of patients with choroidal metastasis. Results: A total of 113 choroidal metastases were diagnosed in 60 eyes of 48 consecutive patients. There were 17 male (35.4) and 31 female (64.6) patients with a mean age of 54.5 years (median: 42; range, 29- 82 years) at the time of choroidal metastasis diagnosis. The median and mean numbers of choroidal metastasis were one and three tumors in each eye respectively. The primary cancer location was found to be the breast in 18 patients (37.5), lung in 11 (22.9), lymphoproliferative system in three (6.3), thyroid in three (6.3), gastrointestinal tract in three (6.3), prostate in two (4.2), brain in one (2.1) and unknown primary in seven (14.5). The most common primary cancer was the breast in females and lung in males. The main ocular symptoms of choroidal metastasis at diagnosis were blurred vision in 42 patients followed by pain in five patients. The choroidal metastasis was unilateral in 36 patients (75) and bilateral in 12 patients (25). Conclusion: The clinical features and primary sites of choroidal metastasis in Iranian patients were similar to those of published reports in this regard. One out of every seven patients had no known primary cancer at the time of choroidal metastasis presentation. © 2013 by the Iranian Society of Ophthalmology

The Impact of Diets Supplemented with Different Forms of Rosemary and BHA on Chemical, Microbial and Sensory Properties of Rainbow Trout Fillet

The objective of this study was to evaluate the effect of different forms and doses of rosemary on chemical, microbial, and sensory properties of rainbow trout fed nine different diets: control (C), 20 g.kg �1 rosemary powder (20RP), 40 g.kg �1 rosemary powder (40RP), 0.3 g.kg �1 rosemary extract (0.3RE), 0.6 g.kg �1 rosemary extract (0.6RE), 0.15 g.kg �1 rosemary nanopowder (0.15RNP), 0.3 g.kg �1 rosemary nanopowder (0.3RNP), 0.15 g.kg �1 butylated hydroxyanisole (BHA) (0.15BHA), and 0.3 g.kg �1 BHA (0.3BHA). After 8 weeks� feeding, the fish fillets were sampled on the 1st, 4th, 8th, 12th, and 16th days and then stored on 4°C. Lower value of pH, peroxide value (PV), total volatile base nitrogen (TVB-N), free fatty acids (FFA), and thiobarbituric acid (TBA) were reported in fish fed with RP, RE, RNP, and BHA; among them, RNP groups had the lowest properties (p < 0.05). Furthermore, lower total viable aerobic bacterial counts (TVC) and psychotropic counts (PTC) were observed in the fillets of the fish fed with rosemary treatments, especially in RNP treatments (7.52�9.41 log 10 CFU.g �1 ), along with a slower spoilage in terms of sensory factors (texture, color, odor, and overall) on the 16th day. Finally, use of natural antioxidant nanorosemary in the diet may positively affect fish fillet quality and delay post-mortem deterioration. © 2019, © 2019 Taylor & Francis Group, LLC

Values of antioxidant activities (ABTS and DPPH) and ferric reducing and chelating powers of gamma-irradiated rosemary extract

This study was carried out to evaluate the effect of the various gamma dose irradiations on the antioxidant activity of rosemary PBS (phosphate-buffered saline) extract. The PBS extract of rosemary was irradiated with gamma rays at the doses of 10, 20, 30, 40 and 50 kGy, and their antioxidant activities were investigated by DPPH (1,1-diphenyl-2-picrylhydrazyl), radical cation ABTS�+ (2,2-Azino-Bis (3-Ethylbenzthiazoline-6-Sulfonic Acid), Diammonium Salt), ferric reducing antioxidant power assay (FRAP) and ferric chelating capacity using ferrozine. The scavenging activities of gamma irradiated rosemary were observed to be significantly higher at 30 and 40 kGy using both methods, DPPH and ABST. Also, the reducing power values of 30 kGy gamma irradiated rosemary were higher than that of non-irradiated (P < 0.05) and the other doses of irradiation could not make any significant difference in reducing power of non-irradiated rosemary. The gamma irradiation of rosemary (at 10-50 kGy), significantly increased the Fe2+ chelating activity compared to non-irradiated rosemary while increasing the absorbed doses reduced Fe2+ chelating activity in rosemary (P < 0.05). There is no significant difference in the rosemary irradiated with 10 kGy and 30 kGy. The gamma irradiated rosemary showed higher antioxidant activities at doses of 30 kGy (79.5 ) and 40 kGy (80 ) with DPPH method, while slightly lower activities were recorded at doses of 30 kGy (34.8 ) and 40 kGy (34.2 ) with ABTS test. Also, results indicate that the 30 kGy might be an effective dose with maximum enhancement in the antioxidant properties of the gamma irradiated rosemary. © 2020 Walter de Gruyter GmbH, Berlin/Boston 2020

Evaluating the Immunity against Hepatitis B Virus and Frequency of HBsAg Positive Cases among Medical Staff of Shahid Beheshti Hospital in Yasuj, 2016

Background & aim: Hepatitis B risk factors are a main consideration among jobs related in healthcare. There is a high risk of hepatitis B infection in health care workers, compared to the general population due to higher exposure to patients infected with the virus. The aim of this study was to evaluate the immunity against hepatitis B virus and frequency of HBsAg positive cases among medical staffs of Shahid Beheshti hospital in Yasuj, Iran.   Methods: The present cross-sectional, descriptive and analytical study was conducted by interviewing 270 personnel of Shahid Beheshti Hospital of Yasuj in 2016. After completing the questionnaire which included demographic and review vaccination records, 5 ml of blood was taken from the participants. Using an ELISA kit specific antibody levels against hepatitis B virus and HBsAg were measured. The data were analyzed by descriptive statistics and chi-square. Results: A total of 112 patients (41.5%) of the subjects were male and 158 (58.5%) were female. The results indicated that a number of seven subjects (6.2%) had no immunity against hepatitis B virus, 68 (25.1%) had border immunity and 195 (72.2%) had complete immunity. 9 patients (3/3 %) were infected with hepatitis B. Among these participants, 5 patients (55.6%) were female and 4 (44.4%) were male. None of them had any sign of obesity, smoking, high risk sexual behavior, blood transfusion and did not develop jaundice.   Conclusion: The present study revealed that the frequency of HBsAg positive cases was in the expected range, and that the samples studied had a favorable safety level. &nbsp

Characterization of Leishmania Parasites Isolated From Kala- azar Patients in Kohgiloyeh and Boyerahmad, Using Semi-Nested PCR

ABSTRACT: Introduction & Objective: Visceral leishmaniasis (VL) is a disease commonly known as Kala-azar caused by protozoan parasites of the genus Leishmania including L. donovani, L. infantum and L. chagasi. VL is sporadic in many areas of Iran and is endemic in a few provinces such as Fars, Azarbayjan, Bushehr, Ardabil and Qom. VL has been reported from some areas of Kohgiloyeh and Boyerahmad and this study aimed to characterize the causative agent of VL in this region. Materials & Methods: Bone marrow sample was obtained from 6 VL patients from children department in Imam Sajad hospital in Yasuj. DNA was extracted from the obtained samples and was checked by semi-nested PCR to determine the species of the parasite. To do that, a segment of minicircle kinetoplast DNA was amplified, using LINR4 and LIN17 primers. Products of PCR were evaluated by electrophoresis, using 1.5% agarose and stained with ethidium bromide. Results: Parasitologically examination of bone marrow smears demonstrated amastigotes form of the parasite in the samples. For mass cultivation, isolated parasites were cultured in diphasic NNN followed by RPMI 1640 media. All the samples produced a 720 bp band in PCR assay. The isolates were compared with referent strains and it was revealed that all the isolates were L. infantum. Conclusion: Findings of this study demonstrated that the causative agent of VL in Kohgiloyeh and Boyerahmad was L. infantum. Further study is needed to explore other aspects of VL in this region