| 1. |
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| 2. |
- Axfors, Cathrine, et al.
(författare)
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Association between convalescent plasma treatment and mortality in COVID-19 : a collaborative systematic review and meta-analysis of randomized clinical trials
- 2021
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Ingår i: BMC Infectious Diseases. - : BioMed Central (BMC). - 1471-2334. ; 21:1
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Forskningsöversikt (refereegranskat)abstract
- Background: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, ). Methods: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. Results: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I-2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. Conclusions: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care.
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| 3. |
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| 4. |
- Micah, Angela E., et al.
(författare)
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Tracking development assistance for health and for COVID-19 : a review of development assistance, government, out-of-pocket, and other private spending on health for 204 countries and territories, 1990-2050
- 2021
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Ingår i: The Lancet. - : Elsevier. - 0140-6736 .- 1474-547X. ; 398:10308, s. 1317-1343
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Forskningsöversikt (refereegranskat)abstract
- Background The rapid spread of COVID-19 renewed the focus on how health systems across the globe are financed, especially during public health emergencies. Development assistance is an important source of health financing in many low-income countries, yet little is known about how much of this funding was disbursed for COVID-19. We aimed to put development assistance for health for COVID-19 in the context of broader trends in global health financing, and to estimate total health spending from 1995 to 2050 and development assistance for COVID-19 in 2020. Methods We estimated domestic health spending and development assistance for health to generate total health-sector spending estimates for 204 countries and territories. We leveraged data from the WHO Global Health Expenditure Database to produce estimates of domestic health spending. To generate estimates for development assistance for health, we relied on project-level disbursement data from the major international development agencies' online databases and annual financial statements and reports for information on income sources. To adjust our estimates for 2020 to include disbursements related to COVID-19, we extracted project data on commitments and disbursements from a broader set of databases (because not all of the data sources used to estimate the historical series extend to 2020), including the UN Office of Humanitarian Assistance Financial Tracking Service and the International Aid Transparency Initiative. We reported all the historic and future spending estimates in inflation-adjusted 2020 US$, 2020 US$ per capita, purchasing-power parity-adjusted US$ per capita, and as a proportion of gross domestic product. We used various models to generate future health spending to 2050. Findings In 2019, health spending globally reached $8. 8 trillion (95% uncertainty interval [UI] 8.7-8.8) or $1132 (1119-1143) per person. Spending on health varied within and across income groups and geographical regions. Of this total, $40.4 billion (0.5%, 95% UI 0.5-0.5) was development assistance for health provided to low-income and middle-income countries, which made up 24.6% (UI 24.0-25.1) of total spending in low-income countries. We estimate that $54.8 billion in development assistance for health was disbursed in 2020. Of this, $13.7 billion was targeted toward the COVID-19 health response. $12.3 billion was newly committed and $1.4 billion was repurposed from existing health projects. $3.1 billion (22.4%) of the funds focused on country-level coordination and $2.4 billion (17.9%) was for supply chain and logistics. Only $714.4 million (7.7%) of COVID-19 development assistance for health went to Latin America, despite this region reporting 34.3% of total recorded COVID-19 deaths in low-income or middle-income countries in 2020. Spending on health is expected to rise to $1519 (1448-1591) per person in 2050, although spending across countries is expected to remain varied. Interpretation Global health spending is expected to continue to grow, but remain unequally distributed between countries. We estimate that development organisations substantially increased the amount of development assistance for health provided in 2020. Continued efforts are needed to raise sufficient resources to mitigate the pandemic for the most vulnerable, and to help curtail the pandemic for all. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.
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| 5. |
- Razavi, Homie A., et al.
(författare)
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Hepatitis D double reflex testing of all hepatitis B carriers in low-HBV- and high-HBV/HDV-prevalence countries
- 2023
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Ingår i: JOURNAL OF HEPATOLOGY. - : Elsevier. - 0168-8278 .- 1600-0641. ; 79:2, s. 576-580
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Tidskriftsartikel (refereegranskat)abstract
- Hepatitis D virus (HDV) infection occurs as a coinfection with hepatitis B and increases the risk of hepatocellular carcinoma, decompensated cirrhosis, and mortality compared to hepatitis B virus (HBV) monoinfection. Reliable estimates of the prevalence of HDV infection and disease burden are essential to formulate strategies to find coinfected individuals more effectively and efficiently. The global prevalence of HBV infections was estimated to be 262,240,000 in 2021. Only 1,994,000 of the HBV in-fections were newly diagnosed in 2021, with more than half of the new diagnoses made in China. Our initial estimates indicated a much lower prevalence of HDV antibody (anti-HDV) and HDV RNA positivity than previously reported in published studies. Ac-curate estimates of HDV prevalence are needed. The most effective method to generate estimates of the prevalence of anti-HDV and HDV RNA positivity and to find undiagnosed individuals at the national level is to implement double reflex testing. This re-quires anti-HDV testing of all hepatitis B surface antigen-positive individuals and HDV RNA testing of all anti-HDV-positive in-dividuals. This strategy is manageable for healthcare systems since the number of newly diagnosed HBV cases is low. At the global level, a comprehensive HDV screening strategy would require only 1,994,000 HDV antibody tests and less than 89,000 HDV PCR tests. Double reflex testing is the preferred strategy in countries with a low prevalence of HBV and those with a high prevalence of both HBV and HDV. For example, in the European Union and North America only 35,000 and 22,000 cases, respectively, will require anti-HDV testing annually.
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| 6. |
- Razavi-Shearer, Devin M., et al.
(författare)
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Adjusted estimate of the prevalence of hepatitis delta virus in 25 countries and territories
- 2024
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Ingår i: JOURNAL OF HEPATOLOGY. - 0168-8278 .- 1600-0641. ; 80:2, s. 232-242
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Tidskriftsartikel (refereegranskat)abstract
- Background & Aims: Hepatitis delta virus (HDV) is a satellite RNA virus that requires the hepatitis B virus (HBV) for assembly and propagation. Individuals infected with HDV progress to advanced liver disease faster than HBV-monoinfected individuals. Recent studies have estimated the global prevalence of anti-HDV antibodies among the HBV-infected population to be 5-15%. This study aimed to better understand HDV prevalence at the population level in 25 countries/territories. Methods: We conducted a literature review to determine the prevalence of anti-HDV and HDV RNA in hepatitis B surface antigen (HBsAg)-positive individuals in 25 countries/territories. Virtual meetings were held with experts from each setting to discuss the findings and collect unpublished data. Data were weighted for patient segments and regional heterogeneity to estimate the prevalence in the HBV-infected population. The findings were then combined with The Polaris Observatory HBV data to estimate the anti-HDV and HDV RNA prevalence in each country/territory at the population level. Results: After adjusting for geographical distribution, disease stage and special populations, the anti-HDV prevalence among the HBsAg+ population changed from the literature estimate in 19 countries. The highest anti-HDV prevalence was 60.1% in Mongolia. Once adjusted for the size of the HBsAg+ population and HDV RNA positivity rate, China had the highest absolute number of HDV RNA+ cases. Conclusions: We found substantially lower HDV prevalence than previously reported, as prior meta-analyses primarily focused on studies conducted in groups/regions that have a higher probability of HBV infection: tertiary care centers, specific risk groups or geographical regions. There is large uncertainty in HDV prevalence estimates. The implementation of reflex testing would improve estimates, while also allowing earlier linkage to care for HDV RNA+ individuals. The logistical and economic burden of reflex testing on the health system would be limited, as only HBsAg+ cases would be screened.
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| 7. |
- Ademuyiwa, Adesoji O., et al.
(författare)
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Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
- 2016
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Ingår i: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
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| 8. |
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| 9. |
- Gerkin, RC, et al.
(författare)
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The best COVID-19 predictor is recent smell loss: a cross-sectional study
- 2020
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Ingår i: medRxiv : the preprint server for health sciences. - : Cold Spring Harbor Laboratory.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- BackgroundCOVID-19 has heterogeneous manifestations, though one of the most common symptoms is a sudden loss of smell (anosmia or hyposmia). We investigated whether olfactory loss is a reliable predictor of COVID-19.MethodsThis preregistered, cross-sectional study used a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified singular and cumulative predictors of COVID-19 status and post-COVID-19 olfactory recovery.ResultsBoth C19+ and C19-groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both single and cumulative feature models (ROC AUC=0.72), with additional features providing negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms, such as fever or cough. Olfactory recovery within 40 days was reported for ∼50% of participants and was best predicted by time since illness onset.ConclusionsAs smell loss is the best predictor of COVID-19, we developed the ODoR-19 tool, a 0-10 scale to screen for recent olfactory loss. Numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4<OR<10), which can be deployed when viral lab tests are impractical or unavailable.
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| 10. |
- Warsame, Marian, et al.
(författare)
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High therapeutic efficacy of artemether-lumefantrine and dihydroartemisinin-piperaquine for the treatment of uncomplicated falciparum malaria in Somalia
- 2019
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Ingår i: Malaria Journal. - : Springer Science and Business Media LLC. - 1475-2875. ; 18
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Tidskriftsartikel (refereegranskat)abstract
- Background: Artemether-lumefantrine (AL) and dihydroartemisinin-piperaquine (DHA/PPQ) are the recommended first- and second-line treatments, respectively, for uncomplicated falciparum malaria in Somalia. The studies reported here were conducted to assess the efficacy of these artemisinin-based combinations and the mutations in Plasmodium falciparum K13-propeller (Pfk13) domain and amplification in Pfplasmepsin 2 (Pfpm2) gene in Somalia. Methods: One-arm prospective studies were conducted to assess the clinical and parasitological responses to DHA/PPQ and AL at two sites in 2016 and 2017, respectively, using the standard WHO protocol. The patterns of molecular markers associated with artemisinin and PPQ resistance were investigated for the first time in Somalia. Results: A total of 339 patients were enrolled with 139 for AL and 200 for DHA/PPQ. With AL, no parasite recurrence was observed among patients treated at either site, corresponding to 100% clinical and parasitological responses. For DHA-PPQ, an adequate clinical and parasitological response rate > 97% was observed. All study patients on both treatments at both sites were parasite-free on day 3. Of the 138 samples with interpretable results for the polymorphism in Pfk13, only one (0.7%), from Bosaso, contained a non-synonymous mutation (R622I), which is not one of the known markers of artemisinin resistance. No Pfpm2 amplification was observed among the 135 samples with interpretable results. Conclusions: AL and DHA/PPQ were highly effective in the treatment of uncomplicated falciparum malaria, and there was no evidence of resistance to artemisinin or PPQ. These two combinations are thus relevant in the chemotherapeutic strategy for malaria control in Somalia.
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| 11. |
- Al-Rukn, S, et al.
(författare)
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Stroke in the Middle-East and North Africa: A 2-year prospective observational study of intravenous thrombolysis treatment in the region. Results from the SITS-MENA Registry
- 2020
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Ingår i: International journal of stroke : official journal of the International Stroke Society. - : SAGE Publications. - 1747-4949. ; 15:9, s. 980-987
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Tidskriftsartikel (refereegranskat)abstract
- Intravenous thrombolysis for acute ischemic stroke in the Middle-East and North African (MENA) countries is still confined to the main urban and university hospitals. This was a prospective observational study to examine outcomes of intravenous thrombolysis-treated stroke patients in the MENA region compared to the non-MENA stroke cohort in the SITS International Registry. Results Of 32,160 patients with ischemic stroke registered using the SITS intravenous thrombolysis protocol between June 2014 and May 2016, 500 (1.6%) were recruited in MENA. Compared to non-MENA (all p < 0.001), median age in MENA was 55 versus 73 years, NIH Stroke Scale score 12 versus 9, onset-to-treatment time 138 versus 155 min and door-to-needle time 54 min versus 64 min. Hypertension was the most reported risk factor, but lower in MENA (51.7 vs. 69.7%). Diabetes was more frequent in MENA (28.5 vs. 20.8%) as well as smoking (20.8 vs. 15.9%). Hyperlipidemia was less observed in MENA (17.6 vs. 29.3%). Functional independence (mRS 0–2) at seven days or discharge was similar (53% vs. 52% in non-MENA), with mortality slightly lower in MENA (2.3% vs. 4.8%). SICH rates by SITS-MOST definition were low (<1.4%) in both groups. Conclusions Intravenous thrombolysis patients in MENA were younger, had more severe strokes and more often diabetes. Although stroke severity was higher in MENA, short-term functional independency and mortality were not worse compared to non-MENA, which could partly be explained by younger age and shorter OTT in MENA. Decreasing the burden of stroke in this young population should be prioritized.
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| 12. |
- Jonauskaite, Domicele, et al.
(författare)
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A comparative analysis of colour–emotion associations in 16–88-year-old adults from 31 countries
- 2024
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Ingår i: British Journal of Psychology. - : John Wiley and Sons Ltd. - 0007-1269 .- 2044-8295. ; 115:2, s. 275-
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Tidskriftsartikel (refereegranskat)abstract
- As people age, they tend to spend more time indoors, and the colours in their surroundings may significantly impact their mood and overall well-being. However, there is a lack of empirical evidence to provide informed guidance on colour choices, irrespective of age group. To work towards informed choices, we investigated whether the associations between colours and emotions observed in younger individuals also apply to older adults. We recruited 7393 participants, aged between 16 and 88 years and coming from 31 countries. Each participant associated 12 colour terms with 20 emotion concepts and rated the intensity of each associated emotion. Different age groups exhibited highly similar patterns of colour–emotion associations (average similarity coefficient of.97), with subtle yet meaningful age-related differences. Adolescents associated the greatest number but the least positively biased emotions with colours. Older participants associated a smaller number but more intense and more positive emotions with all colour terms, displaying a positivity effect. Age also predicted arousal and power biases, varying by colour. Findings suggest parallels in colour–emotion associations between younger and older adults, with subtle but significant age-related variations. Future studies should next assess whether colour–emotion associations reflect what people actually feel when exposed to colour.
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| 13. |
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| 14. |
- Zahra, Maram Hussein, et al.
(författare)
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Alpinia zerumbet (Pers.) : Food and Medicinal Plant with Potential In Vitro and In Vivo Anti-Cancer Activities
- 2019
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Ingår i: Molecules. - : MDPI AG. - 1431-5157 .- 1420-3049. ; 24:13
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Tidskriftsartikel (refereegranskat)abstract
- Background/Aim: Plants play an important role in anti-cancer drug discovery, therefore, the current study aimed to evaluate the biological activity of Alpinia zerumbet (A. zerumbet) flowers. Methods: The phytochemical and biological criteria of A. zerumbet were in vitro investigated as well as in mouse xenograft model. Results: A. zerumbet extracts, specially CH2Cl2 and MeOH extracts, exhibited the highest potent anti-tumor activity against Ehrlich ascites carcinoma (EAC) cells. The most active CH2Cl2 extract was subjected to bioassay-guided fractionation leading to isolatation of the naturally occurring 5,6-dehydrokawain (DK) which was characterized by IR, MS, H-1-NMR and C-13-NMR. A. zerumbet extracts, specially MeOH and CH2Cl2 extracts, exhibited significant inhibitory activity towards tumor volume (TV). Furthermore, A. zerumbet extracts declined the high level of malonaldehyde (MDA) as well as elevated the levels of superoxide dismutase (SOD) and catalase (CAT) in liver tissue homogenate. Moreover, DK showed anti-proliferative action on different human cancer cell lines. The recorded IC50 values against breast carcinoma (MCF-7), liver carcinoma (Hep-G2) and larynx carcinoma cells (HEP-2) were 3.08, 6.8, and 8.7 mu g/mL, respectively. Conclusion: Taken together, these findings open the door for further investigations in order to explore the potential medicinal properties of A. zerumbet.
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| 15. |
- Abdelaziz, Omar Y., et al.
(författare)
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Conceptual Design of a Kraft Lignin Biorefinery for the Production of Valuable Chemicals via Oxidative Depolymerization
- 2020
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Ingår i: ACS Sustainable Chemistry & Engineering. - : American Chemical Society (ACS). - 2168-0485. ; 8:23, s. 8823-8829
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Tidskriftsartikel (refereegranskat)abstract
- Lignin is the most abundant aromatic biopolymer on Earth, and its aromatic structure makes it a promising platform for the production of biobased chemicals and other valuable building blocks. The valorization of lignin into chemicals currently presents a challenge, and its facilitation is key in the development of viable lignocellulosic biorefinery processes. This study presents a conceptual design for a recently demonstrated process for lignin oxidative depolymerization. Modeling, simulation, and analysis were performed based on experimental data to assess the viability of the process. Mass and energy balances and main design data were determined for a 700 t/y kraft lignin biorefinery. The production capacity of aromatic chemicals, including vanillin, vanillic acid, guaiacol, and acetovanillone, was 0.3 kg aromatics/kg net lignin use. A heat-integrated process design is suggested, and the energy demands and the CO2 emissions are evaluated and compared. Assuming an interest rate of 10% and a plant lifetime of 10 years, the return on investment was calculated to be 14%, indicating that such a biorefinery is viable. A sensitivity analysis was carried out to assess the impact of the vanillin selling price and the cost of lignin on the profitability of the process. A quantitative investigation of process sustainability resulted in an E-factor of ∼1.6 for the entire synthetic route, that is, 38% material efficiency. The findings of this study underline the need for further research to develop efficient lignin conversion technologies with attractive yields in order to increase profitability on an industrial scale.
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| 16. |
- Al-Rabiah, Abdulrahman A., et al.
(författare)
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Development of a Biomass Gasification Process for the Coproduction of Methanol and Power from Red Sea Microalgae
- 2022
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Ingår i: Energies. - : MDPI AG. - 1996-1073. ; 15:21
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Tidskriftsartikel (refereegranskat)abstract
- In this study, an algae biomass gasification process using a dual fluidized bed with combined power and methanol cogeneration was developed. The gasification process was modeled using Aspen Plus and validated using experimental data of two microalgae species (Nannochloropsis oculata and Dunaliella salina) commonly found on the western coast of Saudi Arabia. The impacts of different operating conditions, including the gasifier temperature, steam-to-biomass ratio, and algae-char split ratio, on the compositions of four main gases (CO, CO2, CH4, and H2) were investigated. The results of the parametric studies indicated that the gasification temperature has a significant effect on the composition of the synthesis gas, where 700–850 °C was the ideal operating range for gasification. Altering the ratio of biomass to steam showed a slightly smaller effect on the synthesis gas composition. The char split ratio should be kept below 75% to ensure an adequate heat supply to the process. The proposed process successfully converted 45.7% of the biomass feed to methanol at a production capacity of 290 metric tons per day. On the other hand, 38 MW of electricity capacity was generated in the combined power cycle.
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| 17. |
- Al-Rabiah, Abdulrahman A., et al.
(författare)
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Effect of styrene-butadiene-styrene copolymer modification on properties of Saudi bitumen
- 2016
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Ingår i: Petroleum Science and Technology. - : Informa UK Limited. - 1532-2459 .- 1091-6466. ; 34:4, s. 321-327
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Tidskriftsartikel (refereegranskat)abstract
- This research investigates the effects of styrene-butadiene-styrene (SBS) copolymer and other plastomers on the behavior of Saudi bitumen. Three bitumen samples, extracted from three Saudi oil refineries, namely Ras Tanura, Riyadh, and Yanbu, were used in this study. The bitumen samples were mixed with different modifiers in various compositions, forming polymer modified bitumens (PMBs). Elasticity parameters, such as ductility and elastic recovery were measured and evaluated. Characteristics of raw bitumen were analyzed to observe the compatibility of bitumen with SBS and plastomers. Bitumen samples were suitable for SBS modification and SBS PMBs showed superior elasticity behaviors compared to plastomer blends.
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| 18. |
- Al-Rabiah, Abdulrahman A., et al.
(författare)
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Performance of nanoporous carbon membrane for hydrogen recovery
- 2018
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Ingår i: Journal of the Chemical Society of Pakistan. - 0253-5106. ; 40:1, s. 43-51
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this work is to study the performance of nanoporous carbon membrane for hydrogen recovery from off-gas streams. The study is based on a rigorous mathematical model which can predict the performance of nanoporous selective surface flow (SSF) carbon membrane. Basically, the developed model is based on two transport mechanisms: the dusty gas flow through porous media and the surface adsorption-diffusion. The model was employed to simulate the hydrogen recovery from off-gas stream using SSF carbon membrane at different operating conditions. The separation performance of hydrogen-hydrocarbon mixture by nanoporous carbon membrane was evaluated and described. A comparison between the model simulation and the experimental data related to hydrogen recovery from off-gas streams shows good agreement. A parametric study is further carried out to show the effects of pressure at the membrane feed and permeate sides. The effects of flow-rate and type of sweep gas at the membrane permeate side on hydrogen recovery are also shown. SSF membrane illustrates a significant potential to be used for hydrogen recovery from refinery off-gas streams.
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| 19. |
- Al Rukn, S, et al.
(författare)
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Stroke in the Middle-East and North Africa: A 2-year prospective observational study of stroke characteristics in the region-Results from the Safe Implementation of Treatments in Stroke (SITS)-Middle-East and North African (MENA)
- 2019
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Ingår i: International journal of stroke : official journal of the International Stroke Society. - : SAGE Publications. - 1747-4949. ; 14:7, s. 715-722
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Tidskriftsartikel (refereegranskat)abstract
- Stroke incidence and mortality are reported to have increased in the Middle-East and North African (MENA) countries during the last decade. This was a prospective observational study to examine the baseline characteristics of stroke patients in the MENA region and to compare the MENA vs. the non-MENA stroke cohort in the Safe Implementation of Treatments in Stroke (SITS) International Registry. Results Of the 13,822 patients with ischemic and hemorrhagic stroke enrolled in the SITS-All Patients Protocol between June 2014 and May 2016, 5897 patients (43%) were recruited in MENA. The median onset-to-door time was 5 h (IQR: 2:20–13:00), National Institutes of Health Stroke Scale (NIHSS) score was 8 (4–13) and age was 65 years (56–76). Hypertension (66%) and diabetes (38%) were the prevailing risk factors; large artery stenosis > 50% (25.3%) and lacunar strokes (24.1%) were the most common ischemic stroke etiologies. In comparison, non-MENA countries displayed an onset-to-door time of 5:50 h (2:00–18:45), a median of NIHSS 6 (3–14), and a median age of 66 (56–76), with other large vessel disease and cardiac embolism as the main ischemic stroke etiologies. Hemorrhagic strokes (10%) were less common compared to non-MENA countries (13.9%). In MENA, only a low proportion of patients (21%) was admitted to stroke units. Conclusions MENA patients are slightly younger, have a higher prevalence of diabetes and slightly more severe ischemic strokes, commonly of atherosclerotic or microvascular etiology. Admission into stroke units and long-term follow-up need to be improved. It is suspected that cardiac embolism and atrial fibrillation are currently underdiagnosed in MENA countries.
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| 20. |
- Alegiry, Mohamed H., et al.
(författare)
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Attitudes Toward Psychological Disorders and Alternative Medicine in Saudi Participants
- 2021
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Ingår i: Frontiers in Psychiatry. - : Frontiers Media S.A.. - 1664-0640. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Background: This study was designed to investigate Saudis' attitudes toward mental distress and psychotropic medication, attribution of causes, expected side effects, and to analyze participants' expectations toward alternative or complementary medicine using aromatic and medicinal plants, through a survey.Method: The study included 674 participants (citizens and residents in Saudi Arabia) who were randomly contacted via email and social media and gave their consent to complete a questionnaire dealing with 39 items that can be clustered in six parts. Descriptive statistics and Chi-square for cross-tabulation were generated using SPSS.Results: Among the 664 participants, 73.4% believed that there are some positive and negative outcomes of psychotropic medication. Participants (72.0%) think that the most important reason leading to psychological disorders is mainly due to the loss of a relative or beloved person, and 73.9% considered psychic session as one of the possible treatments of psychological disorders. Surprisingly, only 18.8% of the participants agreed that medicinal and aromatic plants could be a possible treatment of the psychological disorder. Participants (82%) consider that physicians are the most trustful and preferred source of information about alternative and complementary medicine.
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| 21. |
- Alharbi, Essa A., et al.
(författare)
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Formation of High-Performance Multi-Cation Halide Perovskites Photovoltaics by delta-CsPbI3/delta-RbPbI3 Seed-Assisted Heterogeneous Nucleation
- 2021
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Ingår i: Advanced Energy Materials. - : John Wiley & Sons. - 1614-6832 .- 1614-6840. ; 11:16
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Tidskriftsartikel (refereegranskat)abstract
- The performance of perovskite solar cells is highly dependent on the fabrication method; thus, controlling the growth mechanism of perovskite crystals is a promising way towards increasing their efficiency and stability. Herein, a multi-cation halide composition of perovskite solar cells is engineered via the two-step sequential deposition method. Strikingly, it is found that adding mixtures of 1D polymorphs of orthorhombic delta-RbPbI3 and delta-CsPbI3 to the PbI2 precursor solution induces the formation of porous mesostructured hexagonal films. This porosity greatly facilitates the heterogeneous nucleation and the penetration of FA (formamidinium)/MA (methylammonium) cations within the PbI2 film. Thus, the subsequent conversion of PbI2 into the desired multication cubic alpha-structure by exposing it to a solution of formamidinium methylammonium halides is greatly enhanced. During the conversion step, the delta-CsPbI3 also is fully integrated into the 3D mixed cation perovskite lattice, which exhibits high crystallinity and superior optoelectronic properties. The champion device shows a power conversion efficiency (PCE) over 22%. Furthermore, these devices exhibit enhanced operational stability, with the best device retaining more than 90% of its initial value of PCE under 1 Sun illumination with maximum power point tracking for 400 h.
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| 22. |
- Hamasy, Abdulrahman M
(författare)
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Effects of mutations in lymphoid malignancy and immunodeficiency disease
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Mutations are responsible for causing various human diseases, including several types of cancer and immunodeficiency syndromes. They can either be involved directly in the pathogenesis of the disease or by influencing the treatment efficacy and cause failure of the patient’s response to a specific therapy by adapting the targeted cell to resist the treatment. In paper I, we generated amino acid substitution variations of BTK at ibrutinib binding site C481, and performed functional analysis for the corresponding proteins. We have also studied various phosphorylations, which are affected by ibrutinib treatment and put our results in a structure-function context. Herein, we demonstrated that substitution of cysteine 481 by threonine (C481T) retained the kinase activity and caused ibrutinib resistance. So we identified a new escape mutant for irreversible BTK inhibitors, which we predict to be found in patients. BTK kinase is completely inactivated by amino acid (codon) replacement of C481 with arginine, phenylalanine, tryptophan or tyrosine, while the activity is severely impaired when C481 replaced by glycine. In paper II, we have compared the role of N-terminal region domains in the regulation of SYK fusion kinases in terms of phosphorylation, activation, stability and localization. Upon translocation, SYK contributes its kinase domain into two known fusion-proteins, ITK-SYK and TEL-SYK. We have also generated analogous B-cell fusion kinase, BTK-SYK for comparison. The fusion kinases showed differential activation, localization and sensitivity to various inhibitors. Here, we report the activation-mediated nuclear translocation of ITK-SYK, which is rarely seen among kinases. This unique feature of ITK-SYK is therefore of general interest, as its potential relation to ITK-SYK’s transforming capability. In paper III, we have identified a hypomorphic mutation in PGM3 gene replacing isoleucine 322 with threonine in a family with immunodeficient children, described previously. The mutation is severely destabilized and impaired the enzymatic activity of the protein, causing the described phenotype.
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| 23. |
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| 24. |
- Joshi, Ritika, et al.
(författare)
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Low Fouling Nanostructured Cellulose Membranes for Ultrafiltration in Wastewater Treatment
- 2023
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Ingår i: Membranes. - : MDPI AG. - 2077-0375. ; 13:2
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Tidskriftsartikel (refereegranskat)abstract
- Ultrafiltration (UF) is a common technique used in wastewater treatments. However, the issue of membrane fouling in UF can greatly hinder the effectiveness of the treatments. This study demonstrated a low-fouling composite cellulose membrane system based on microfibrillated cellulose (MFC) and silica nanoparticle additives. The incorporation of 'non-spherical' silica nanoparticles was found to exhibit better structural integration in the membrane (i.e., minimal aggregation of silica nanoparticles in the membrane scaffold) as compared to spherical silica. The resulting composite membranes were tested for UF using local wastewater, where the best-performing membrane exhibited higher permeation flux than commercial polyvinylidene difluoride (PVDF) and polyether sulfone (PES) membranes while maintaining a high separation efficiency (similar to 99.6%) and good flux recovery ratio (>90%). The analysis of the fouling behavior using different models suggested that the processes of cake layer formation and pore-constriction were probably two dominant fouling mechanisms, likely due to the presence of humic substances in wastewater. The demonstrated cellulose composite membrane system showed low-fouling and high restoration capability by a simple hydraulic cleaning method due to the super hydrophilic nature of the cellulose scaffold containing silica nanoparticles.
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| 25. |
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