10 research outputs found
Self-adaptive Controllers for Renewable Energy Communities Based on Transformer Loading Estimation
In this paper, self-adaptive controllers for renewable energy communities based on data-driven approach are proposed to mitigate the voltage rise and transformer congestion at the community level. In the proposed approach, the transformer loading percentage is estimated by the trained data-driven model, which uses the extreme gradient boosting regression algorithm based on a measurement set acquired from critical coupling points of the communities. To avoid voltage rise issues, the droop control parameters (i.e., voltage threshold for P - V, Q - V curves) are adaptively tuned based on the solar irradiance availability and estimated transformer loading. The proposed approach has been tested in the IEEE European LV distribution network. Results showed that the control approach could effectively reduce 22.2 % of the total overloaded instances, while still keeping voltage magnitude in the operation range. This method can help DSOs manage voltage violation and congestion without further communication
Isolation and selection of fungal species from the compost with the cellulolytic activity and resistance topathogenic phythium and phytophthora capsici fungi on the pepper plants
Unknown input fractional-order functional observer design for one-side Lipschitz time-delay fractional-order systems
Investigating the properties and hydrolysis ability of poly-lactic acid/chitosan nanocomposites using polycaprolactone
Poly-lactic acid (PLA) has been widely applied in the medical field (in biomedicines such as medical capsules, surgical sutures and suture wounds) owing to its high biodegradability, good biocompatibility and ability to be dissolved in common solvents. Chitosan (CS) is an abundant polysaccharide and a cationic polyelectrolyte present in nature. In this study, the combination of PLA and CS has been used to form PLA/CS nanocomposites having the advantages of both the original components. To enhance the dispersibility and compatibility between PLA and CS in the PLA/CS nanocomposites, polycaprolactone (PCL) is added as a compatibilizer. The Fourier Transform Infrared spectroscopies prove the existence of the interactions of PCL with PLA and CS. A more regular dispersion of CS of 200-400 nm particle size, is observed in the PLA matrix of the PLA/CS nanocomposites containing PCL, through the Field Emission Scanning Electron Microscopy images. The appearance of one glass transition temperature (T) value of PLA/CS/PCL nanocomposites occuring between the T values of PLA and CS in DSC diagrams confirms the improvement in the compatibility between PLA and CS, due to the presence of PCL. The TGA result shows that PCL plays an important role in enhancing the thermal stability of PLA/CS/PCL nanocomposites. The hydrolysis of PLA/CS/PCL nanocomposites in alkaline and phosphate buffer solutions was investigated. The obtained results show that the PLA/CS/PCL nanocomposites have slower hydrolysis ability than the PLA/CS composites
Guillain–Barré Syndrome due to COVID-19 Vero Cell Vaccination Associated with Concomitant COVID-19 Infection-induced ARDS and Treated Successfully by Therapeutic Plasma Exchange: A First Case Report from Vietnam
Abstract Post-vaccination adverse reactions have been reported with varying symptoms and severity owing to research and production time pressures during the coronavirus disease 2019 (COVID-19) pandemic. In this article, we report a rare case of Guillain–Barré syndrome (GBS) in a patient with COVID-19 with acute respiratory distress syndrome (ARDS) after receiving Sinopharm's Vero Cell vaccine (China). The patient who was initially negative for COVID-19 was diagnosed with GBS based on paralysis that developed from the lower extremities to the upper extremities, as confirmed by cytoalbuminologic dissociation in the cerebrospinal fluid. The patient's condition worsened with ARDS caused by COVID-19 infection during the hospital stay, and SpO2 decreased to 83% while receiving oxygen through a non-rebreather mask (15 l/min) on day 6. The patient was treated with standard therapy for severe COVID-19, invasive mechanical ventilation, and five cycles of therapeutic plasma exchange (TPE) with 5% albumin replacement on day 11 due to severe progression. The patient was weaned off the ventilator on day 28, discharged on day 42, and was completely healthy after 6 months without any neurological sequelae until now. Our report showed the potential of TPE for GBS treatment in critically ill patients with COVID-19 after COVID-19 vaccination
Simulated Microgravity Induces the Proliferative Inhibition and Morphological Changes in Porcine Granulosa Cells
Astronauts are always faced with serious health problems during prolonged spaceflights. Previous studies have shown that weightlessness significantly affects the physiological function of female astronauts, including a change in reproductive hormones and ovarian cells, such as granulosa and theca cells. However, the effects of microgravity on these cells have not been well characterized, especially in granulosa cells. This study aimed to investigate the effects of simulated microgravity (SMG) on the proliferation and morphology of porcine granulosa cells (pGCs). pGC proliferation from the SMG group was inhibited, demonstrated by the reduced O.D. value and cell density in the WST-1 assay and cell number counting. SMG-induced pGCs exhibited an increased ratio of cells in the G0/G1 phase and a decreased ratio of cells in the S and G2/M phase. Western blot analysis indicated a down-regulation of cyclin D1, cyclin-dependent kinase 4 (cdk4), and cyclin-dependent kinase 6 (cdk6), leading to the prevention of the G1-S transition and inducing the arrest phase. pGCs under the SMG condition showed an increase in nuclear area. This caused a reduction in nuclear shape value in pGCs under the SMG condition. SMG-induced pGCs exhibited different morphologies, including fibroblast-like shape, rhomboid shape, and pebble-like shape. These results revealed that SMG inhibited proliferation and induced morphological changes in pGCs
Predictive Factors of Mortality in Patients with Severe COVID-19 Treated in the Intensive Care Unit: A Single-Center Study in Vietnam
Abstract Introduction The fourth outbreak of COVID-19 with the delta variant in Vietnam was very fierce due to the limited availability of vaccines and the lack of healthcare resources. During that period, the high mortality of patients with severe and critical COVID-19 caused many concerns for the health system, especially the intensive care units. This study aimed to analyze the predictive factors of death and survival in patients with severe and critical COVID-19. Methods We conducted a cross-sectional and descriptive study on 151 patients with severe and critical COVID-19 hospitalized in the Intensive Care Unit of Binh Duong General Hospital. Results Common clinical symptoms of severe and critical COVID-19 included shortness of breath (97.4%), fatigue (89.4%), cough (76.8%), chest pain (47.7%), loss of smell (48.3%), loss of taste (39.1%), and headache (21.2%). The abnormal biochemical features were leukopenia (2.1%), anemia, thrombocytopenia (18%), hypoxia with low PaO2 (34.6%), hypocapnia with reduced PaCO2 (29.6%), and blood acidosis (18.4%). Common complications during hospitalization were septic shock (15.2%), cardiogenic shock (5.3%), and embolism (2.6%). The predictive factors of death were being female, age > 65 years, cardiovascular comorbidity, thrombocytopenia (< 137.109/l), and hypoxia at inclusion or after the first week or blood acidosis (pH < 7.28). The use of a high dose of corticosteroids reduced the mortality during the first 3 weeks of hospitalization but significantly increased risk of death after 3 and 4 weeks. Conclusions Common clinical symptoms, laboratory features, and death-related complications of critical and severe COVID-19 patients were found in Vietnamese patients during the fourth wave of the COVID-19 pandemic. The results of this study provide new insight into the predictive factors of mortality for patients with severe and critical COVID-19