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1.
Sci Rep ; 14(1): 13280, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858409

RESUMO

Recently, hydrogen-based distributed generators (DG) have gained significant attention for modern energy generation systems. These modem DGs are typically outfitted with power electronics converters, resulting in harmonic pollution. Furthermore, increasing the growth of modern nonlinear loads may result in exceeding the harmonic beyond the permitted level. This research proposes a framework for optimal incorporation of inverter-based distributed generation (a fuel cell connected to an AC distribution system) for minimizing power losses, enhancing the voltage profile, and limiting both total and individual harmonic distortion according to the IEEE-519 standard. In addition, for accounting system sustainability, the proposed framework considers load variation and the expected rise in demand. Therefore, the suggested framework comprises three stages, which include fundamental and harmonic power flow analysis. The first stage identifies the optimal size and location of the DG in relation to the base load operating condition. While, with the optimal DG of the first stage, the amount of harmonic pollution may violate the limits during a high level of nonlinear load penetration, as a result, the second stage resizes the DG, considering the connection bus of the first stage, to mitigate the harmonics and optimize the system at a higher level of nonlinear load penetration. Both the first and second stages are performed off-line, while the third stage optimizes the system operation during run time according to loading conditions, harmonic pollution, and the available DG capacity of the previous stages. DG's harmonic spectrum is represented according to recently issued IEEE 1547-2018 for permissible DG's current distortion limits. The suggested approach is applied and evaluated using an IEEE 33-bus distribution system for various combinations of linear and nonlinear loads. For run-time operation throughout the day, the presented framework reduces the energy losses from 5.281 to 2.452 MWh/day (about 53.57% energy savings). This saving is associated with voltage profile enhancement without violating the permissible standard levels of harmonics and other system constraints.

2.
Campbell Syst Rev ; 20(2): e1414, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38887375

RESUMO

Background: High-income countries offer social assistance (welfare) programs to help alleviate poverty for people with little or no income. These programs have become increasingly conditional and stringent in recent decades based on the premise that transitioning people from government support to paid work will improve their circumstances. However, many people end up with low-paying and precarious jobs that may cause more poverty because they lose benefits such as housing subsidies and health and dental insurance, while incurring job-related expenses. Conditional assistance programs are also expensive to administer and cause stigma. A guaranteed basic income (GBI) has been proposed as a more effective approach for alleviating poverty, and several experiments have been conducted in high-income countries to investigate whether GBI leads to improved outcomes compared to existing social programs. Objectives: The aim of this review was to conduct a synthesis of quantitative evidence on GBI interventions in high-income countries, to compare the effectiveness of various types of GBI versus "usual care" (including existing social assistance programs) in improving poverty-related outcomes. Search Methods: Searches of 16 academic databases were conducted in May 2022, using both keywords and database-specific controlled vocabulary, without limits or restrictions on language or date. Sources of gray literature (conference, governmental, and institutional websites) were searched in September 2022. We also searched reference lists of review articles, citations of included articles, and tables of contents of relevant journals in September 2022. Hand searching for recent publications was conducted until December 2022. Selection Criteria: We included all quantitative study designs except cross-sectional (at one timepoint), with or without control groups. We included studies in high income countries with any population and with interventions meeting our criteria for GBI: unconditional, with regular payments in cash (not in-kind) that were fixed or predictable in amount. Although two primary outcomes of interest were selected a priori (food insecurity, and poverty level assessed using official, national, or international measures), we did not screen studies on the basis of reported outcomes because it was not possible to define all potentially relevant poverty-related outcomes in advance. Data Collection and Analysis: We followed the Campbell Collaboration conduct and reporting guidelines to ensure a rigorous methodology. The risk of bias was assessed across seven domains: confounding, selection, attrition, motivation, implementation, measurement, and analysis/reporting. We conducted meta-analyses where results could be combined; otherwise, we presented the results in tables. We reported effect estimates as standard mean differences (SMDs) if the included studies reported them or provided sufficient data for us to calculate them. To compare the effects of different types of interventions, we developed a GBI typology based on the characteristics of experimental interventions as well as theoretical conceptualizations of GBI. Eligible poverty-related outcomes were classified into categories and sub-categories, to facilitate the synthesis of the individual findings. Because most of the included studies analyzed experiments conducted by other researchers, it was necessary to divide our analysis according to the "experiment" stage (i.e., design, recruitment, intervention, data collection) and the "study" stage (data analysis and reporting of results). Main Results: Our searches yielded 24,476 records from databases and 80 from other sources. After screening by title and abstract, the full texts of 294 potentially eligible articles were retrieved and screened, resulting in 27 included studies on 10 experiments. Eight of the experiments were RCTs, one included both an RCT site and a "saturation" site, and one used a repeated cross-sectional design. The duration ranged from one to 5 years. The control groups in all 10 experiments received "usual care" (i.e., no GBI intervention). The total number of participants was unknown because some of the studies did not report exact sample sizes. Of the studies that did, the smallest had 138 participants and the largest had 8019. The risk of bias assessments found "some concerns" for at least one domain in all 27 studies and "high risk" for at least one domain in 25 studies. The risk of bias was assessed as high in 21 studies due to attrition and in 22 studies due to analysis and reporting bias. To compare the interventions, we developed a classification framework of five GBI types, four of which were implemented in the experiments, and one that is used in new experiments now underway. The included studies reported 176 poverty-related outcomes, including one pre-defined primary outcome: food insecurity. The second primary outcome (poverty level assessed using official, national, or international measures) was not reported in any of the included studies. We classified the reported outcomes into seven categories: food insecurity (as a category), economic/material, physical health, psychological/mental health, social, educational, and individual choice/agency. Food insecurity was reported in two studies, both showing improvements (SMD = -0.57, 95% CI: -0.65 to -0.49, and SMD = -0.41, 95% CI: -0.57 to -0.26) which were not pooled because of different study designs. We conducted meta-analyses on four secondary outcomes that were reported in more than one study: subjective financial well-being, self-rated overall physical health, self-rated life satisfaction, and self-rated mental distress. Improvements were reported, except for overall physical health or if the intervention was similar to existing social assistance. The results for the remaining 170 outcomes, each reported in only one study, were summarized in tables by category and subcategory. Adverse effects were reported in some studies, but only for specific subgroups of participants, and not consistently, so these results may have been due to chance. Authors' Conclusions: The results of the included studies were difficult to synthesize because of the heterogeneity in the reported outcomes. This was due in part to poverty being multidimensional, so outcomes covered various aspects of life (economic, social, psychological, educational, agency, mental and physical health). Evidence from future studies would be easier to assess if outcomes were measured using more common, validated instruments. Based on our analysis of the included studies, a supplemental type of GBI (provided along with existing programs) may be effective in alleviating poverty-related outcomes. This approach may also be safer than a wholesale reform of existing social assistance approaches, which could have unintended consequences.

3.
Sci Rep ; 14(1): 10059, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698062

RESUMO

Microgrids require efficient energy management systems to optimize the operation of microgrid sources and achieve economic efficiency. Bi-level energy management model is proposed in this paper to minimize the operational cost of a grid-tied microgrid under load variations and uncertainties in renewable sources while satisfying the various technical constraints. The first level is day ahead scheduling of generation units based on day ahead forecasting of renewable energy sources and load demand. In this paper, a recent meta-heuristic algorithm called Coronavirus Herd Immunity Optimizer (CHIO) is used to solve the problem of day-ahead scheduling of batteries, which is a complex constrained non-linear optimization problem, while the Lagrange multiplier method is used to determine the set-point of the Diesel Generator (DG). The second level of the proposed EMS is rescheduling and updating the set-points of sources in real-time according to the actual solar irradiance, wind speed, load, and grid tariff. In this paper, a novel real-time strategy is proposed to keep the economic operation during real-time under uncertainties. The obtained results show that the CHIO-based bi-level EMS demonstrates an optimal economic operation for a grid-connected microgrid in real-time when there are uncertainties in weather, utility tariffs, and load forecasts.

4.
Ann Med Surg (Lond) ; 86(5): 3066-3071, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38694386

RESUMO

Introduction and importance: Moyamoya disease (MMD) is a condition characterized by progressive narrowing of arteries in the brain and abnormal development of small collateral vessels. It is commonly found in East Asia but has never been reported in Palestine. Case presentation: A 2-year-old female, part of a twin born to non-consanguineous parents, presented with recurring seizures and developmental regression. The physical examination revealed signs of hypotonia, reflex abnormalities, and bilateral Babinski signs. Comprehensive laboratory tests and imaging investigations confirmed the diagnosis of MMD, marking this patient as the reported case in Palestine. Clinical discussion: The diagnostic criteria for this condition were revised in 2021 to focus on findings seen in angiography and magnetic resonance angiography (MRA) scans. MMD has not been curative so far, and the management is focused on preventing complications, sometimes with surgical revascularization, including its different approaches: direct, indirect, and a combination of both. Conclusion: This case highlights the importance of identifying MMD in regions where it is uncommon to be diagnosed. It emphasizes the need for diagnosis and appropriate intervention to reduce complications.

5.
Sci Rep ; 14(1): 8518, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609403

RESUMO

The multi-component glass system has a composition of 10K2O-10ZnO-55 B2O3-(25-x)V2O5-xBi2O3 (x = 4, 5, 7.5, 9, 10 mol%) are synthesized by the melt-quenching method. Using X-ray diffraction examination, the amorphous phase in the material was confirmed. The physical characteristics of the produced compositions are examined using density (D) and molar volume (Vm). Calculations of physical properties showed that adding Bi2O3 from 4 to 10 mol% increased the glass density from 2.7878 to 3.3617 g cm-3 and decreased the molar volume from 40.4196 to 38.5895 cm3/mol. Studies of glass samples using the FTIR show bands of absorption for oxides in different structural groups. Octahedral [ BiO 6 ], [ BO 4 ], and tetrahedral [ BO 3 ] structural units are observed in the present glass matrices. The cutoff wavelength ( λ C ), and optical band gap energy were determined using UV absorption spectra. The increase in non-bridging oxygens can be linked to the decrease in optical band gap energy ( E opt ) (direct and indirect) and the increase in cutoff wavelength with an increase in Bi2O3 content. This is attributed to the existence of bismuth ions and the creation of non-bridging oxygens. Besides that, the values of optical parameters, viz., optical electronegativity, refractive index, and molar refractivity, are calculated. The metallization criterion values are less than 1 and the glass samples exhibit an increased tendency towards metallization. Both the conductivity and the dielectric constant increase with the rise in Bi2O3 content, however, the dielectric loss and the impedance reduce. The behavior and values of conductivity for the studied glasses reveal the semiconducting properties of all glass samples. These results suggest that the produced glass samples may be employed as amorphous semiconductors in electronics and memory switching devices.

6.
Br Poult Sci ; 65(3): 242-249, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38507293

RESUMO

*1. In many countries, eggs are not refrigerated and must be stored at room temperature. The objective of this study was to explore the effects of dietary oregano oil (275 mg/kg; ORE) versus an unsupplemented control diet (CON) on laying hens on the shelf life and fatty acid profile of eggs.2. Treatments were randomly distributed into 10 pens containing 27 birds each. A total of 200 eggs were collected from both groups on the same day and were stored for either 0, 10, 21 and 35 d. At each storage time, egg yolks were analysed for fatty acid profile and lipid peroxidation.3. The main indicator of lipid peroxidation, malondialdehyde (MDA), was significantly lower in ORE eggs compared to CON eggs (p = 0.001). Storage time had a significant impact on MDA concentrations (p = 0.023), with the highest found after 35 d. Significant differences were found for individual fatty acids, saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). Palmitic acid, stearic acid, oleic acid, linoleic acid and arachidonic acid were significantly lower in ORE eggs compared to CON eggs (p < 0.05). Palmitoleic acid (p = 0.002), linolenic acid (p = 0.001) and docosahexaenoic acid (DHA, p = 0.001) were significantly higher in ORE eggs.4. Storage only affected oleic, linolenic, linoleic, arachidonic and docosahexaenoic acids (p < 0.05). Total SFA, MUFA, n-6 and ratio of n-3 to n-6 (n-3:n-6) PUFA were significantly higher in CON eggs (p < 0.05). The ratio of SFA to PUFA (SFA:PUFA, p = 0.005) and total n-3 PUFA (p = 0.001) were significantly higher in ORE eggs.5. The n-3:n-6 ratio was significantly impacted by treatment (p = 0.021) and storage (p = 0.031) with no significant interaction. This ratio is important for human health indication and could lead to the development of designer eggs.


Assuntos
Ração Animal , Galinhas , Dieta , Suplementos Nutricionais , Ovos , Ácidos Graxos , Armazenamento de Alimentos , Óleos Voláteis , Origanum , Animais , Origanum/química , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Ração Animal/análise , Suplementos Nutricionais/análise , Ovos/análise , Dieta/veterinária , Feminino , Óleos Voláteis/química , Distribuição Aleatória , Peroxidação de Lipídeos/efeitos dos fármacos , Temperatura
7.
Sci Rep ; 14(1): 4548, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402330

RESUMO

The integration of microgrids into the existing power system framework enhances the reliability and efficiency of the utility grid. This manuscript presents an innovative mathematical paradigm designed for the optimization of both the structural and operational aspects of a grid-connected microgrid, leveraging the principles of Demand-Side Management (DSM). The focus of this work lies in a comprehensive exploration of the implications brought about by the Renewable Generation-Based Dynamic Pricing Demand Response (RGDP-DR) mechanism, particularly in terms of its influence on the optimal microgrid configuration, considering perspectives from end-users and the utility entity. This inquiry is rooted in a holistic assessment that encompasses technical and economic performance benchmarks. The RGDP-induced DR framework adeptly addresses the needs of the consumer base, showcasing notable efficiency and economic feasibility. To address the intricate nonlinear optimization challenge at hand, we employ an evolutionary algorithm named the "Dandelion Algorithm" (DA). A rigorous comparative study is conducted to evaluate the efficacy of four optimization techniques, affirming the supremacy of the proposed DA. Within this discourse, the complexity of microgrid sizing is cast as a dual-objective optimization task. The twin objectives involve minimizing the aggregate annual outlay and reducing emissions. The results of this endeavor unequivocally endorse the superiority of the DA over its counterparts. The DA demonstrates exceptional proficiency in orchestrating the most cost-effective microgrid and consumer invoice, surpassing the performance of alternative optimization methodologies.

8.
Radiography (Lond) ; 30(1): 353-358, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38134628

RESUMO

INTRODUCTION: Accurately distinguishing between benign and malignant vertebral compression fractures is crucial for clinical management. This study evaluated the predictive accuracy of diffusion-weighted imaging (DWI) in differentiating the cause of vertebral fractures using MRI. METHODS: A longitudinal cross-over study was conducted at Jinnah Postgraduate Medical Centre (JPMC) Karachi from July 2018 to January 2021. Patients with vertebral compression fractures underwent T1-weighted, T2-weighted, and DWI imaging with ADC mapping on a 1.5 T MRI scanner. Imaging findings were compared with histopathologic results and clinical follow-up. Sensitivity, specificity, and ROC curve analyses were performed. RESULTS: The study enrolled 303 patients with a mean age of 43.6 ± 10.9 years, of whom 118 were male. DWI demonstrated high accuracy in predicting the cause of vertebral compression fractures, with a sensitivity of 96.2 %, a specificity of 76.2 %, and an area under the ROC curve of 0.857. The optimal ADC cut-off value was 0.82 × 10˄-3 mm˄2/s, which yielded a positive predictive value of 79.7 % and a negative predictive value of 95.4 %. CONCLUSIONS: DWI is a safe and non-invasive imaging modality with excellent predictive accuracy in differentiating between benign and malignant vertebral compression fractures. Iso- or hypointensity of collapsed vertebral bodies on DWI suggests a benign lesion, while T2-weighted hyperintensity is highly indicative of malignancy. Low signal on ADC is also highly indicative of malignant vertebral fractures. Incorporating DWI improves accuracy in assessing vertebral lesions, especially when standard sequences are inconclusive. IMPLICATIONS FOR PRACTICE: DWI revolutionizes vertebral compression fracture diagnosis, distinguishing between benign and malignant cases. This precision guides treatment decisions, minimizing the necessity for invasive procedures like biopsy. As a safe and reliable imaging method, DWI elevates patient care, ensuring accurate diagnostics and improved outcomes.


Assuntos
Fraturas por Compressão , Fraturas da Coluna Vertebral , Neoplasias da Coluna Vertebral , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/etiologia , Estudos Cross-Over , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/efeitos adversos
9.
PLoS One ; 18(11): e0293140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37948401

RESUMO

INTRODUCTION: Overcrowding in the emergency departments (ED) is linked to adverse clinical outcomes, a negative impact on patient safety, patient satisfaction, and physician efficiency. We aimed to design a medical admission prediction scoring system based on readily available clinical data during ED presentation. METHODS: In this retrospective cross-sectional study, data on ED presentations and medical admissions were extracted from the Emergency and Internal Medicine departments of a tertiary care facility in Qatar. Primary outcome was medical admission. RESULTS: Of 320299 ED presentations, 218772 were males (68.3%). A total of 11847 (3.7%) medical admissions occurred. Most patients were Asians (53.7%), followed by Arabs (38.7%). Patients who got admitted were older than those who did not (p <0.001). Admitted patients were predominantly males (56.8%), had a higher number of comorbid conditions and a higher frequency of recent discharge (within the last 30 days) (p <0.001). Age > 60 years, female gender, discharge within the last 30 days, and worse vital signs at presentations were independently associated with higher odds of admission (p<0.001). These factors generated the scoring system with a cut-off of >17, area under the curve (AUC) 0.831 (95% CI 0.827-0.836), and a predictive accuracy of 83.3% (95% CI 83.2-83.4). The model had a sensitivity of 69.1% (95% CI 68.2-69.9), specificity was 83.9% (95% CI 83.7-84.0), positive predictive value (PPV) 14.2% (95% CI 13.8-14.4), negative predictive value (NPV) 98.6% (95% CI 98.5-98.7) and positive likelihood ratio (LR+) 4.28% (95% CI 4.27-4.28). CONCLUSION: Medical admission prediction scoring system can be reliably applied to the regional population to predict medical admissions and may have better generalizability to other parts of the world owing to the diverse patient population in Qatar.


Assuntos
Hospitalização , Alta do Paciente , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Transversais , Serviço Hospitalar de Emergência
10.
Cent Eur J Immunol ; 48(2): 97-110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692025

RESUMO

Hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) play a crucial role in the context of viral infections and their associated diseases. The link between HSCs and HPCs and disease status in COVID-19 patients is largely unknown. This study aimed to monitor the kinetics and contributions of HSCs and HPCs in severe and non-severe COVID-19 patients and to evaluate their diagnostic performance in differentiating between healthy and COVID-19 patients as well as severe and non-severe cases. Peripheral blood (PB) samples were collected from 48 COVID-19 patients, 16 recovered, and 27 healthy controls and subjected to deep flow cytometric analysis to determine HSCs and progenitor cells. Their diagnostic value and correlation with C-reactive protein (CRP), D-dimer, and ferritin levels were determined. The percentages of HSCs and common myeloid progenitors (CMPs) declined significantly, while the percentage of multipotent progenitors (MPPs) increased significantly in COVID-19 patients. There were no significant differences in the percentages of megakaryocyte-erythroid progenitors (MEPs) and granulocyte-macrophage progenitors (GMPs) between all groups. Severe COVID-19 patients had a significantly low percentage of HSCs, CMPs, and GMPs compared to non-severe cases. Contrarily, the levels of CRP, D-dimer, and ferritin increased significantly in severe COVID-19 patients. MPPs and CMPs showed excellent diagnostic performance in distinguishing COVID-19 patients from healthy controls and severe from non-severe COVID-19 patients, respectively. Collectively, our study indicated that hematopoietic stem and progenitor cells are significantly altered by COVID-19 and could be used as therapeutic targets and diagnostic biomarkers for severe COVID-19.

11.
J Family Med Prim Care ; 12(2): 295-304, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37091022

RESUMO

Background: Exclusive breastfeeding (EBF) describes infants who were only breastfed for 6 months. Many Saudi mothers have suboptimal breastfeeding practices. Therefore, this study aims to assess breastfeeding knowledge and determine barriers to EBF among mothers attending primary health care centers in Jazan City. Methods: A descriptive cross-sectional study was done that included all mothers attending the PHC centers. Data were collected through a self-administered questionnaire. Results: Most study participants understand breastfeeding's health benefits for babies and mothers, but most believe that synthetic milk is the best alternative for working mothers to feed their babies. A percentage of 66.7 of mothers practiced breastfeeding during the first 6 months of the child's life. EBF shows a significant relationship with knowledge and barriers. Sixty percent of mothers have never had any information about breastfeeding; the primary source was from their mothers and only 31.4% from hospital staff. Most respondents disagreed with statements of barriers to EBF, which elicits an unexpected response. Conclusions: Most participants have good knowledge concerning breastfeeding benefits for both mother and infant and disagreed on the mentioned barriers for EBF that include lack of breastmilk, deficiency of information, and working conditions.

12.
Mol Biol Rep ; 50(4): 3053-3062, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683082

RESUMO

BACKGROUND: In homozygous ß-thalassemia, the primary genetic modifiers affecting the clinical severity of ß-thalassemia are genetic variants and the ability to reduce globin chain imbalance, thus resulting in a milder form of thalassemia. However, there are few reports on the molecular genetics of ß-thalassemia in Iraq. METHODS: We performed PCR and DNA sequencing on 40 Iraqi patients who were clinically suspected of having ß-thalassemia. RESULTS: The first genetic sequencing study was conducted in Maysan Governate, Iraq, using patients from various locations to identify novel mutations. There were five novel mutations: 294.T>C 12% (city center and Almajar district), 205. C>T 25% (city center, Alsalam, and Almashrah districts), 289.G>A 38% (Almaymuna and Gleat Salih districts), 49.T>C 32% (city center), and 624.C>A 32% (city center). These mutations were identified among ß-thalassemia patients by two regions of HBB gene 696 bp and 861 bp. CONCLUSIONS: The discovery of new genetic variants helps predict the severity of ß-thalassemia disease. There are relatively few studies in molecular genetics of ß-thalassemia in Iraq, and the new mutations reported here will provide valuable data for the prevention and control of ß-thalassemia in Maysan Governate, Iraq. The results can lead to new genetic sequencing investigations for other Iraqi regions.


Assuntos
Talassemia , Talassemia beta , Humanos , Talassemia beta/epidemiologia , Talassemia beta/genética , Iraque/epidemiologia , Genótipo , Globinas beta/genética , Alelos , Talassemia/genética , Mutação/genética
13.
Qatar Med J ; 2022(1): 18, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35321121

RESUMO

Quality improvement and patient safety are cornerstones to the delivery of effective patient care. The introduction of a quality improvement curriculum for medical students and trainee physicians can have a significant effect on their understanding of the science of improvement and its role in improving the quality of healthcare delivery and patient safety. The article describes the development and implementation of a quality improvement curriculum for trainee physicians in the department of internal medicine at a tertiary care center in Qatar through online training courses, workshops, didactic activities, and trainee-led quality improvement projects.

14.
Dalton Trans ; 51(9): 3531-3545, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35142775

RESUMO

The synthesis of six N,N'-substituted thiourea ligands (L1a-L3b) was achieved in two steps. A corresponding extensive series of Cu(I), Cu(II), Ni(II) and Zn(II) complexes (1-24) with varying formulations were synthesised from these ligands by the reaction of a 1 : 1 or a 1 : 2 mixture of Cu(II), Ni(II) and Zn(II) perchlorate or chloride salts. Complexes 1-24 have been comprehensively characterised by mass spectrometry, elemental analysis, UV-vis., IR, and 1H and 13C{1H} NMR spectroscopies where applicable. The X-ray crystal structures were obtained for eight examples: [(L1a)2Cu]ClO4 (1), [(L1c)2Zn](ClO4)2 (4), [(L2a)2Cu]ClO4 (6), [(L2c)2Ni](ClO4)2 (7), [(L1b)2Cu](ClO4) (15), [(L1b)CuCl] (16), [(L4)2CuCl2] (19) and [(L3b)CuClO4] (21). These studies reveal that L1c and L2c represent ligands that have undergone cleavage during reaction with the metal salt; L4 represents an intramolecular rearrangement (via a Hugershoff reaction) of L2b; and in most cases Cu(II) is reduced to Cu(I) during the ligand reaction. The X-ray crystal structures also reveal that 1, 4, 6, 15 and 16 are monometallic species in the solid state; that Cu(I) in 1, 6, 15 and 16 and Zn(II) in 4 are arranged in a distorted tetrahedral geometry; that Cu(I) in 21 adopts a trigonal planar geometry; and that in 7 and 19 the Ni(II) and Cu(II) centres, respectively, possess square planar geometry. Preliminary studies on the biological activity (using the Malaria Sybr Green I Fluorescence assay) of the thiourea containing complexes suggests that the d10 complexes, and increased ligand stoichiometries, may afford higher potency.


Assuntos
Complexos de Coordenação
15.
Front Public Health ; 9: 779410, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900920

RESUMO

Introduction: The objective of this study is to investigate the COVID-19 outbreak and its successful containment in a long-term care facility, Qatar. Materials and Methods: It was a retrospective case series of 24 COVID-19 positive patients inclusive of elderly, patient attenders, and front-liners from 06th to 18th June 2020. Laboratory, radiological, and treatment findings were assessed from electronic records. Results: The outbreak management team concluded that despite all the pre-existing preventive measures implemented at the start of the pandemic, there was still evidence of lapses in infection control practices such as breach of infection control protocols like improper use of personal protective equipment. The infection prevention and control team promptly reassessed and implemented more stringent infection control methods and practices that successfully contained the outbreak on July 1, 2020. Among the seven elderly patients, the average age was 76.28 years ± SD25.5 and all were females. 57% of the patients were symptomatic. The most common comorbidities were Dementia (57%), Diabetes mellitus (43%), Coronary Artery Disease (43%), and Seizures (43%). Ground glass appearances in the lungs were found in 29% of the patients. Among the three deceased patients, Dementia and Coronary Artery Disease were the common comorbidities. Persistent elevation in blood glucose levels was observed among all patients during this period of infection. Conclusion: Elderlies in long-term care facilities are with certain pre-existing comorbidities which makes them more prone to develop COVID-19 complications. Thus, intensive infection control measures like ongoing education and awareness, staff compliance monitoring, quick contact tracing, visitor policy revision, ongoing patient and caregivers monitoring are inevitable recommendations for effective outbreak prevention and management.


Assuntos
COVID-19 , Assistência de Longa Duração , Idoso , Surtos de Doenças/prevenção & controle , Humanos , Casas de Saúde , Catar/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
16.
Eur Rev Med Pharmacol Sci ; 25(23): 7449-7459, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34919247

RESUMO

OBJECTIVE: Currently, no NASH-specific therapies are approved by the US Food and Drug Administration. This study aimed to compare the clinical effect of vitamin E (Vit. E), Ursodeoxycholic Acid (UDCA) and pentoxifylline (PTX) on Egyptian patients with NASH with exploration of their possible roles on inflammatory cytokines and chemokines mainly Interleukin 6 (IL6) and Monocyte Chemoattractant Protein-1 (CCL2/MCP-1). PATIENTS AND METHODS: We conducted a 3-month, randomized, single-blind study in 102 Egyptian NASH patients who were divided into three groups; group 1 received Vit. E 400 mg twice a day, group 2 received UDCA 250 mg twice a day and group 3 received PTX 400 mg twice daily. Liver aminotransferases (AST, ALT), IL6, CCL2/MCP-1, albumin, bilirubin, and lipid panel were measured both before and after intervention intake. RESULTS: A significant decrease was found in liver aminotransferases, serum cytokine and chemokine in participants after Vit. E, UDCA or PTX intake. Compared to the UDCA and PTX groups, liver aminotransferases, serum cytokine and chemokine showed a more statistically significant reduction after Vit. E administration (50%, 43%, 57% and 55% for ALT, AST, IL6 and CCL2/MCP-1, respectively). In contrast, other biochemical tests showed non-significant change after any drug intake. None of the tested drugs showed significant safety issues in this population. CONCLUSIONS: Treatment with Vit. E, UDCA and PTX was both safe and effective in improving hepatic aminotransferases and inflammatory markers in Egyptian NASH patients. The superior effect of Vit. E compared to UDCA and PTX may suggest that oxidative stress plays a key role in disease progression of NASH patients. Moreover, IL6 and CCL2/MCP-1 may be used with or without ALT for treatment evaluation of NASH people.


Assuntos
Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Pentoxifilina/uso terapêutico , Ácido Ursodesoxicólico/uso terapêutico , Vitamina E/uso terapêutico , Adulto , Antioxidantes/efeitos adversos , Antioxidantes/uso terapêutico , Colagogos e Coleréticos/efeitos adversos , Colagogos e Coleréticos/uso terapêutico , Progressão da Doença , Egito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Pentoxifilina/efeitos adversos , Inibidores de Fosfodiesterase/efeitos adversos , Inibidores de Fosfodiesterase/uso terapêutico , Estudos Prospectivos , Método Simples-Cego , Resultado do Tratamento , Ácido Ursodesoxicólico/efeitos adversos , Vitamina E/efeitos adversos
17.
Asian Pac J Cancer Prev ; 22(11): 3533-3541, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837910

RESUMO

BACKGROUND: Breast cancer is one of the most frequent malignancies in women, and it is a major cause of cancer death worldwide, as well as one of the leading causes of cancer mortality. Traditional herbal therapy has been widely used in some developing countries as a complementary and alternative technique. Because of their low toxicity, medicinal edible plants have been allowed to minimize the risk of breast cancer and other diseases. The heart of Phoenix dactylifera is a well-known, safe, and common edible part of the P. dactylifera plant (Hilawi variety). The biological properties of heart of P. dactylifera are unclear, and the appeal warrants further investigation. The aim of this study is to look into the chemical compositions, antioxidant and anticancer properties of heart of P. dactylifera extract obtained via microwave-assisted extraction. METHODS: Microwave-assisted extraction, ethanol solvent, gas chromatography-mass spectroscopy (GC-MS) analysis, DPPH assay, MTT assay, acridine orange/ethidium bromide staining, cell cycle, reactive oxygen species, and apoptosis were all used to evaluate the activity of heart of P. dactylifera. RESULTS: GC-MS was used to identify the chemical compositions of heart of P. dactylifera extract, which revealed about 15 bioactive compounds. The antioxidant activity of heart of P. dactylifera extract was determined to have an IC50 value of 114.2 µg/ml. The cytotoxicity was measured using MCF-7 cells, and the IC50 was reported to be 620.1 µg/ml. The cell cycle was arrested at the G1 gate, resulting in the formation of reactive oxygen species and apoptosis. CONCLUSION: The findings suggested that regular consumption of P. dactylifera heart components is important for nutrition and immune system support in the prevention of breast cancer, and that more research into molecular apoptotic pathways is needed.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Phoeniceae/química , Fitoterapia , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/prevenção & controle , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Células MCF-7 , Espécies Reativas de Oxigênio/metabolismo
18.
BMJ Open Qual ; 10(4)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34815252

RESUMO

Prescription of oxygen therapy has traditionally poor compliance across the globe and mostly given to patients on verbal orders leading to under or overuse. The British Thoracic Society (BTS) guidelines (2017) recommend that oxygen therapy must be prescribed. Our study aimed to assess the prescription practice of oxygen therapy for patients admitted to acute medical assessment unit and general medical wards at Hamad General Hospital, Qatar and to achieve 80% compliance of valid oxygen therapy prescription implementing the quality improvement model against the BTS guidelines.The prescription practice of oxygen therapy was audited between April 2019 and August 2019. Using a Plan, Do, Study, Act (PDSA) model of improvement and multiple interventions was performed in the eight PDSA cycles, including (1) educational sessions for residents/fellows/nurses, (2) introduction of electronic prescription, (3) emails, posters/flyers, (4) nurse-led reminders and (5) re-enforced teaching for new residents. Data were then collected using a questionnaire assessing electronic prescriptions and documentation. Our baseline study regarding oxygen therapy showed limited awareness of BTS guidelines regarding the documentation of initiation and further adjustment of oxygen therapy. There was a lack of compliance with oxygen prescription; none of the patients had a valid prescription on our computer-based prescription (Cerner). The duration, target range and indications of Oxygen therapy were documented in 25% (18/72), 45.8% (33/72) and 42% (30/72) patients, respectively. Oxygen was initiated by communication order only. In a total of 16 weeks period, the repeated PDSA cycles showed significant improvement in safe oxygen prescription practices. Following intervention, oxygen electronic prescription, documentation of indications for oxygen therapy, target oxygen saturation and wean-off plan improved to 93%, 85%, 86 % and 80 %, respectively.We concluded that poor compliance to oxygen therapy Orders is a universal issue, which can be successfully managed using small-scale PDSA cycles to ensure sustained improvement through multidimensional interventions, continuous reinforcement and frequent reassessments.


Assuntos
Oxigênio , Melhoria de Qualidade , Hospitais Gerais , Humanos , Saturação de Oxigênio , Prescrições , Catar
19.
Micron ; 150: 103125, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34352469

RESUMO

Many Tagetes species are known for producing essential oils and commercially useful bioactive compounds. This study investigated the micromorphological features of the internal and external foliar structures of Tagetes minuta that produce and store these compounds. Stereomicroscopy, light microscopy, scanning electron microscopy, transmission electron microscopy, and histochemical analyses were used to examine T. minuta leaves at three developmental stages. The development of the subdermal secretory cavities revealed that the cells undergo autolysis to form a schizolysigenous cavity in the mature leaves. The ultrastructure of the parenchymal sheath and secretory epithelium within the secretory cavity revealed that plastids change to contain lipid and osmiophilic molecules. The histochemical analyses showed that trichomes on the surface of T. minuta leaves appear to be linear and non-glandular but maintain the ability to store bioactive phytocompounds. These are new findings for T. minuta and provide a better understanding of the exudation process, which can help to optimise essential oil production for industrial applications.


Assuntos
Óleos Voláteis , Tagetes , Microscopia Eletrônica de Varredura , Folhas de Planta , Tricomas
20.
J Infect Public Health ; 14(10): 1313-1319, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34281792

RESUMO

BACKGROUND: Understanding COVID-19 infection among health workers and the risk factors for adverse outcomes is important not only for characterizing virus transmission patterns and risk factors for infection, but also for preventing the future infection of health workers and other patients and reducing secondary COVID-19 transmission within health care settings. Our aim was to identify risk factors for infection among health care workers to limit adverse events in health care facilities. SUBJECTS AND METHODS: A total of 336 HCWs from COVID-19 treatment hospitals took part in the study with varying COVID-19 exposure risk depending on job function and working site. All participants were asked about risk factors for COVID-19 infection. RESULTS: Among our participants, 42.6% were medical doctors, 28.6% nurses and 7.4% assistant nurses and 21.4% were others. Forty four percent of participants had work experience 5-10 years. More than half of participants received training in Infection Prevention and Control (IPC) (56.8%) about COVID 19; 91% have hand hygiene facilities and 69% admitted availability of PPE. More than half of participants admitted that they always follow IPC measures. Two thirds of participants (66.7%) had close contact with a patient since admission; 42.3% were present in aerosolizing procedures for patients. Forty two percent of participants had respiratory symptom; the most common was sore throat representing (32.4%). The highest frequency of respiratory symptoms was among of nurses and assistant nurses 51%. Frequency of respiratory symptoms was higher among those who contacted the patient directly or for prolonged period compared to those who do not admitted these contacts. CONCLUSIONS: Risk factors for COVID-19 represented by those who were smokers, nurses and assistant nurses were more liable to catch COVID-19 than doctors as they contacted the patient directly for prolonged period or his/her body fluids, materials or surfaces around him.


Assuntos
COVID-19 , Pessoal de Saúde , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Fatores de Risco
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