Optimum Resilient Operation and Control DC Microgrid Based Electric Vehicles Charging Station Powered by Renewable Energy Sources

This paper introduces an energy management and control method for DC microgrid supplying electric vehicles (EV) charging station. An Energy Management System (EMS) is developed to manage and control power flow from renewable energy sources to EVs through DC microgrid. An integrated approach for controlling DC microgrid based charging station powered by intermittent renewable energies. A wind turbine (WT) and solar photovoltaic (PV) arrays are integrated into the studied DC microgrid to replace energy from fossil fuel and decrease pollution from carbon emissions. Due to the intermittency of solar and wind generation, the output powers of PV and WT are not guaranteed. For this reason, the capacities of WT, solar PV panels, and the battery system are considered decision parameters to be optimized. The optimized design of the renewable energy system is done to ensure sufficient electricity supply to the EV charging station. Moreover, various renewable energy technologies for supplying EV charging stations to improve their performance are investigated. To evaluate the performance of the used control strategies, simulation is carried out in MATLAB/SIMULINK. Document type: Articl

Effects of short term feeding of some marine microalgae on the microbial profile associated with Dicentrarchus labrax post larvae

AbstractThis study investigates the microbial profile and antimicrobial activity of four marine microalgae species, Tetraselmis chuii, Nannochloropsis salina, Isochrysis galbana and Chlorella salina used in aquaculture of Dicentrarchus labrax in the post larval stage to estimate which was the best algal species that could be used as a green water technique and achieving the maximum rate of growth and survival of D. labrax post larvae. The results represented a significant increase in the length and width of D. labrax at p<0.05 recorded in the case of enrichment with I. galbana followed by N. salina, and the most weight was recorded in the case of N. salina as compared with the control. Significant increase in percentage of survival of D. labrax was recorded in the case of C. salina and T. chuii (70% and 60.1%, respectively) as compared with the control (22%). The antibacterial activity (AU) of the different microalgal ethanolic extracts against fish indicator pathogens was determined. The results indicated that the ethanolic extracts of C. salina and T. chuii have the most positive records against the fish indicator pathogens (Escherichia coli, Pseudomonas aeruginosa, Vibrio damsela, Vibrio fluvialis and Aeromonas hydrophila). The current study was extended to determine the GC–MS of ethanolic extract of C. salina and T. chuii. The main constituents detected in the ethanolic extract were organic acids like hexadecanoic acid, octadecanoic acid, and an acyclic diterpene alcohol like phytol

Benign prostatic hyperplasia: Enucleation versus resection using plasmakinetic energy: a prospective randomized study at Zagazig University Hospital

Background: Transuretheral resection of the prostate (TURP) has been the gold standard endoscopic treatment for bladder outlet obstruction (BOO) secondary to benign prostatic hyperplasia (BPH). New technologies have been developed to minimize the morbidity of TURP. Recently, the Gyrus Plasma Kinetic (PK) System is the first bipolar device used in urological practice, as a new modality in treatment of BPH.Objective: To evaluate the efficacy and safety of plasmakinetic enucleation compared to plasmakinetic resection of the prostate in the management of BOO induced by BPH. Patients and Methods: This study was conducted on 58 volunteers from Department of Urology, Faculty of Medicine, Zagazig University between January 2018, and January 2020. Patients were randomized to either plasmakinetic enucleation of the prostate (PKEP) group or plasmakinetic resection of the prostate (PKRP) group. All patients were indicated for surgical treatment (prostate size ≥ 60 g and ≤ 120 g). Results: There were no statistically significant differences between the two groups preoperatively. PKEP resulted in a greater volume of prostatic tissue removal than the PKRP. Tissue retrieved/total operative time in PKEP group was greater than in PKRP group (0.69 gm/min vs 0.67 gm/min respectively). The mean indwelling uretheral catheter time was shorter in PKEP group (34.7 ±4.40 hrs.) than in PKRP (48.79 ±4.31 hrs.). Regarding postoperative complication (early and late), there were no statistically significant differences between the two groups.Conclusions: We concluded that regarding, surgical safety and efficacy PKEP is comparable to PKRP for prostates (60-120 ml). Either PKEP or PKRP can be on an equal footing to TURP as an endoscopic management of BP

Cost Analysis of a Large Solar Plant with Parabolic Trough Concentrators Using Molten Salt Storage Tank

Thermal storage tank is a standout amongst the most encouraging methods in solar thermal power stations operation. Accurate selection of appropriate storage system is a significant parameter to ensure the continuous working of thermal solar station during the absence of the sun. This work describes financial analysis of different locations of a 500MW Solar Plant in Egypt and also thermal tank design. The selected three locations which are investigated in this study are Aswan, EL-Arish and Hurghada to build this challenged size solar station. These locations cover the tree levels of the solar intensity in Egypt. This study is achieved by System Advisor Model (SAM) as financial analysis simulation tool. All the solar thermal power plants are working twenty-four hours per day and with sixteen full load hours of thermal energy storage (TES). Parametric design and cost analysis for each location, comparison between these locations are introduced to select the optimum location for 500MW solar power plant. The results of this study is considered a good orientation for feasibility study for CPS (concentrators parabolic system) projects, and it is needed in all over the world in particular, in Egypt for future to produce clean energy

Prevalence, Profile, and Response to Work-Related Musculoskeletal Disorders among Egyptian Physiotherapists

BACKGROUND: Despite that physiotherapists (PTs) are supposed to have adequate knowledge of musculoskeletal disorders and the different prevention strategies, they are at high risk of developing work-related musculoskeletal disorders (WRMDs). AIM: This study aimed to investigate the prevalence, profile, predictors, and response to WRMDs among Egyptian PTs. METHODS: A self-administrated questionnaire was distributed either manually or via e-mail to 564 PTs with at least two years of working experience. Questions elicited information about the personal and occupational history of the respondents in addition to the experience of WRMDs in the past two years. RESULTS: Four hundred and fourteen respondents (82.6%) reported WRMDs within the last two years, with the lower back as the most common area affected (68.8%). More than half the PTs (54.8%) who sustained a WRMD reported that their injury took place in a private setting. Significant predictors for WRMDs were age (AOR = 0.78; 95% CI = 0.66, 0.91) and number of years of experience in physiotherapy practice (AOR = 1.26; 95% CI = 1.07, 1.49). In response to the injury, about 73.9% of the respondents stated that they did not officially report their injury and 55.8% of them reported losing a half day or more from their work. CONCLUSION: The prevalence of WRMDs among Egyptian physiotherapists is high. Despite socioeconomic and cultural differences between Egypt and other countries, our study findings were consistent with the published reports. Further studies are needed to explore the cultural and psychosocial risk factors of WRMDs

A distributed architecture of parallel buck-boost converters and cascaded control of DC microgrids-real time implementation

To enhance the stability and reliability of the system, the converters’ parallel operation can be cascaded to address the constraints posed by the substantial integration of renewable resources. Buck-boost DC-DC converters are often controlled via a cascaded control approach to allow parallel operation. The converter’s output current and its voltage will be controlled by nested loop control. This study proposes adaptive droop control parameters that are updated and verified online using the principal current sharing loops to minimize the fluctuation in load current sharing. When the converters in the microgrid are paralleled, load sharing will be accomplished using the droop control approach in addition to nested proportional-integral-based voltage and current control loops. To restore the correct voltage across the DC microgrid, an outer addition voltage secondary loop will be used, rectifying any voltage disparities caused by the droop management strategy. Several common load resistances and input voltage variations are used to test the suggested method. Using a linearized model, this work assesses the stability and performance of the proposed method. It then confirms the findings with an adequate model created in MATLAB/SIMULINK, Real-Time Simulation Fundamentals, and hardware-based experiments

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P &lt; 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely