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1.
  • 2021
  • swepub:Mat__t
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2.
  • Thomas, HS, et al. (författare)
  • 2019
  • swepub:Mat__t
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  • Bravo, L, et al. (författare)
  • 2021
  • swepub:Mat__t
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  • Tabiri, S, et al. (författare)
  • 2021
  • swepub:Mat__t
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5.
  • Glasbey, JC, et al. (författare)
  • 2021
  • swepub:Mat__t
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9.
  • Drake, TM, et al. (författare)
  • Surgical site infection after gastrointestinal surgery in children: an international, multicentre, prospective cohort study
  • 2020
  • Ingår i: BMJ global health. - : BMJ. - 2059-7908. ; 5:12
  • Tidskriftsartikel (refereegranskat)abstract
    • Surgical site infection (SSI) is one of the most common healthcare-associated infections (HAIs). However, there is a lack of data available about SSI in children worldwide, especially from low-income and middle-income countries. This study aimed to estimate the incidence of SSI in children and associations between SSI and morbidity across human development settings.MethodsA multicentre, international, prospective, validated cohort study of children aged under 16 years undergoing clean-contaminated, contaminated or dirty gastrointestinal surgery. Any hospital in the world providing paediatric surgery was eligible to contribute data between January and July 2016. The primary outcome was the incidence of SSI by 30 days. Relationships between explanatory variables and SSI were examined using multilevel logistic regression. Countries were stratified into high development, middle development and low development groups using the United Nations Human Development Index (HDI).ResultsOf 1159 children across 181 hospitals in 51 countries, 523 (45·1%) children were from high HDI, 397 (34·2%) from middle HDI and 239 (20·6%) from low HDI countries. The 30-day SSI rate was 6.3% (33/523) in high HDI, 12·8% (51/397) in middle HDI and 24·7% (59/239) in low HDI countries. SSI was associated with higher incidence of 30-day mortality, intervention, organ-space infection and other HAIs, with the highest rates seen in low HDI countries. Median length of stay in patients who had an SSI was longer (7.0 days), compared with 3.0 days in patients who did not have an SSI. Use of laparoscopy was associated with significantly lower SSI rates, even after accounting for HDI.ConclusionThe odds of SSI in children is nearly four times greater in low HDI compared with high HDI countries. Policies to reduce SSI should be prioritised as part of the wider global agenda.
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11.
  • Abbafati, Cristiana, et al. (författare)
  • 2020
  • Tidskriftsartikel (refereegranskat)
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12.
  • Feigin, Valery L., et al. (författare)
  • Global, regional, and national burden of stroke and its risk factors, 1990-2019 : a systematic analysis for the Global Burden of Disease Study 2019
  • 2021
  • Ingår i: Lancet Neurology. - : Elsevier. - 1474-4422 .- 1474-4465. ; 20:10, s. 795-820
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Regularly updated data on stroke and its pathological types, including data on their incidence, prevalence, mortality, disability, risk factors, and epidemiological trends, are important for evidence-based stroke care planning and resource allocation. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) aims to provide a standardised and comprehensive measurement of these metrics at global, regional, and national levels. Methods We applied GBD 2019 analytical tools to calculate stroke incidence, prevalence, mortality, disability-adjusted life-years (DALYs), and the population attributable fraction (PAF) of DALYs (with corresponding 95% uncertainty intervals [UIs]) associated with 19 risk factors, for 204 countries and territories from 1990 to 2019. These estimates were provided for ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage, and all strokes combined, and stratified by sex, age group, and World Bank country income level. Findings In 2019, there were 12.2 million (95% UI 11.0-13.6) incident cases of stroke, 101 million (93.2-111) prevalent cases of stroke, 143 million (133-153) DALYs due to stroke, and 6.55 million (6.00-7.02) deaths from stroke. Globally, stroke remained the second-leading cause of death (11.6% [10.8-12.2] of total deaths) and the third-leading cause of death and disability combined (5.7% [5.1-6.2] of total DALYs) in 2019. From 1990 to 2019, the absolute number of incident strokes increased by 70.0% (67.0-73.0), prevalent strokes increased by 85.0% (83.0-88.0), deaths from stroke increased by 43.0% (31.0-55.0), and DALYs due to stroke increased by 32.0% (22.0-42.0). During the same period, age-standardised rates of stroke incidence decreased by 17.0% (15.0-18.0), mortality decreased by 36.0% (31.0-42.0), prevalence decreased by 6.0% (5.0-7.0), and DALYs decreased by 36.0% (31.0-42.0). However, among people younger than 70 years, prevalence rates increased by 22.0% (21.0-24.0) and incidence rates increased by 15.0% (12.0-18.0). In 2019, the age-standardised stroke-related mortality rate was 3.6 (3.5-3.8) times higher in the World Bank low-income group than in the World Bank high-income group, and the age-standardised stroke-related DALY rate was 3.7 (3.5-3.9) times higher in the low-income group than the high-income group. Ischaemic stroke constituted 62.4% of all incident strokes in 2019 (7.63 million [6.57-8.96]), while intracerebral haemorrhage constituted 27.9% (3.41 million [2.97-3.91]) and subarachnoid haemorrhage constituted 9.7% (1.18 million [1.01-1.39]). In 2019, the five leading risk factors for stroke were high systolic blood pressure (contributing to 79.6 million [67.7-90.8] DALYs or 55.5% [48.2-62.0] of total stroke DALYs), high body-mass index (34.9 million [22.3-48.6] DALYs or 24.3% [15.7-33.2]), high fasting plasma glucose (28.9 million [19.8-41.5] DALYs or 20.2% [13.8-29.1]), ambient particulate matter pollution (28.7 million [23.4-33.4] DALYs or 20.1% [16.6-23.0]), and smoking (25.3 million [22.6-28.2] DALYs or 17.6% [16.4-19.0]). Interpretation The annual number of strokes and deaths due to stroke increased substantially from 1990 to 2019, despite substantial reductions in age-standardised rates, particularly among people older than 70 years. The highest age-standardised stroke-related mortality and DALY rates were in the World Bank low-income group. The fastest-growing risk factor for stroke between 1990 and 2019 was high body-mass index. Without urgent implementation of effective primary prevention strategies, the stroke burden will probably continue to grow across the world, particularly in low-income countries.
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13.
  • Ademuyiwa, Adesoji O., et al. (författare)
  • Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
  • 2016
  • Ingår i: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
  • 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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14.
  • Micah, Angela E., et al. (författare)
  • 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
  • Ingår i: The Lancet. - : Elsevier. - 0140-6736 .- 1474-547X. ; 398:10308, s. 1317-1343
  • 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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15.
  • Potapov, Anton M., et al. (författare)
  • Global fine-resolution data on springtail abundance and community structure
  • 2024
  • Ingår i: Scientific Data. - : Nature Publishing Group. - 2052-4463. ; 11:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Springtails (Collembola) inhabit soils from the Arctic to the Antarctic and comprise an estimated ~32% of all terrestrial arthropods on Earth. Here, we present a global, spatially-explicit database on springtail communities that includes 249,912 occurrences from 44,999 samples and 2,990 sites. These data are mainly raw sample-level records at the species level collected predominantly from private archives of the authors that were quality-controlled and taxonomically-standardised. Despite covering all continents, most of the sample-level data come from the European continent (82.5% of all samples) and represent four habitats: woodlands (57.4%), grasslands (14.0%), agrosystems (13.7%) and scrublands (9.0%). We included sampling by soil layers, and across seasons and years, representing temporal and spatial within-site variation in springtail communities. We also provided data use and sharing guidelines and R code to facilitate the use of the database by other researchers. This data paper describes a static version of the database at the publication date, but the database will be further expanded to include underrepresented regions and linked with trait data.
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17.
  • Wiedorn, Max O., et al. (författare)
  • Megahertz serial crystallography
  • 2018
  • Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 9
  • Tidskriftsartikel (refereegranskat)abstract
    • The new European X-ray Free-Electron Laser is the first X-ray free-electron laser capable of delivering X-ray pulses with a megahertz inter-pulse spacing, more than four orders of magnitude higher than previously possible. However, to date, it has been unclear whether it would indeed be possible to measure high-quality diffraction data at megahertz pulse repetition rates. Here, we show that high-quality structures can indeed be obtained using currently available operating conditions at the European XFEL. We present two complete data sets, one from the well-known model system lysozyme and the other from a so far unknown complex of a beta-lactamase from K. pneumoniae involved in antibiotic resistance. This result opens up megahertz serial femtosecond crystallography (SFX) as a tool for reliable structure determination, substrate screening and the efficient measurement of the evolution and dynamics of molecular structures using megahertz repetition rate pulses available at this new class of X-ray laser source.
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18.
  • Reddy, Hemanth K. N., et al. (författare)
  • Coherent soft X-ray diffraction imaging of coliphage PR772 at the Linac coherent light source
  • 2017
  • Ingår i: Scientia Danica. Series H. Humanistica 4. - : Nature Publishing Group. - 1904-5506 .- 2052-4463. ; 4
  • Tidskriftsartikel (refereegranskat)abstract
    • Single-particle diffraction from X-ray Free Electron Lasers offers the potential for molecular structure determination without the need for crystallization. In an effort to further develop the technique, we present a dataset of coherent soft X-ray diffraction images of Coliphage PR772 virus, collected at the Atomic Molecular Optics (AMO) beamline with pnCCD detectors in the LAMP instrument at the Linac Coherent Light Source. The diameter of PR772 ranges from 65-70 nm, which is considerably smaller than the previously reported similar to 600 nm diameter Mimivirus. This reflects continued progress in XFEL-based single-particle imaging towards the single molecular imaging regime. The data set contains significantly more single particle hits than collected in previous experiments, enabling the development of improved statistical analysis, reconstruction algorithms, and quantitative metrics to determine resolution and self-consistency.
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19.
  • Broomé, Sara, et al. (författare)
  • Going Deeper than Tracking : A Survey of Computer-Vision Based Recognition of Animal Pain and Emotions
  • 2023
  • Ingår i: International Journal of Computer Vision. - : Springer Nature. - 0920-5691 .- 1573-1405. ; 131:2, s. 572-590
  • Tidskriftsartikel (refereegranskat)abstract
    • Advances in animal motion tracking and pose recognition have been a game changer in the study of animal behavior. Recently, an increasing number of works go ‘deeper’ than tracking, and address automated recognition of animals’ internal states such as emotions and pain with the aim of improving animal welfare, making this a timely moment for a systematization of the field. This paper provides a comprehensive survey of computer vision-based research on recognition of pain and emotional states in animals, addressing both facial and bodily behavior analysis. We summarize the efforts that have been presented so far within this topic—classifying them across different dimensions, highlight challenges and research gaps, and provide best practice recommendations for advancing the field, and some future directions for research. 
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20.
  • Ellabban, Mohamed A., et al. (författare)
  • Assessment of Freestyle Local Facial Perforator Flaps for Coverage of Facial Defects
  • 2021
  • Ingår i: The Journal of Craniofacial Surgery. - : Wolters Kluwer. - 1049-2275 .- 1536-3732. ; 32:2, s. e122-e125
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE: To assess local freestyle facial perforator flaps in the reconstruction of small to medium-sized facial defects.MATERIALS AND METHODS: In a case series, local freestyle perforator flaps were used in Suez Canal University Hospital to reconstruct 28 facial defects in 26 patients between 2017 and 2019. Adequate perforators were identified near those defects and flaps were designed as propeller or VY advancement. Four scales from the FACE-Q (satisfaction with facial appearance, satisfaction with the outcome, psychological function, and appearance-related psychosocial distress) and 2 scales from the SCAR-Q (Appearance scale and Symptom scale) were used as well as the observer part of the Patient and Observer Scar Assessment Scale. The mean follow up period was 10 months.RESULTS: Complete reconstruction was achieved in all cases with a high rate of patient satisfaction which was assessed by FACE-Q and SCAR-Q. Moreover, observer assessment by Patient and Observer Scar Assessment Scale score showed high patient satisfaction with the scars with a mean (SD) 15.5 (3.4) and there was a positive correlation between subjective and objective: results (r2 from 0.27 to 0.41, P < 0.01). Regarding complications, bulkiness occurred in 2 flaps, congestion in 2 flaps, dehiscence in 1 flap, and tip necrosis in 5 flaps. Accordingly, secondary intervention in the form of medicinal leech therapy was used in 3 flaps, delayed closure for the dehisced flap and debulking for 1 flap.CONCLUSIONS: Local freestyle perforator flap reconstruction is one of the recommended techniques for small to medium-sized facial defects which gives a high aesthetic outcome and patient satisfaction.
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21.
  • Munke, Anna, et al. (författare)
  • Data Descriptor : Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source
  • 2016
  • Ingår i: Scientific Data. - : Nature Publishing Group. - 2052-4463. ; 3
  • Tidskriftsartikel (refereegranskat)abstract
    • Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a wellcharacterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 mu m diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 angstrom ngstrom were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here.
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22.
  • Aboelnaga, Ahmed, et al. (författare)
  • Microbial cellulose dressing compared with silver sulphadiazine for the treatment of partial thickness burns: A prospective, randomised, clinical trial
  • 2018
  • Ingår i: Burns. - : Elsevier. - 0305-4179 .- 1879-1409. ; 44:8, s. 1982-1988
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundThe current treatment for partial thickness burns at the trial site is silver sulphadiazine, as it minimises bacterial colonisation of wounds. Its deleterious effect on wound healing, together with the need for repeated, often painful, procedures, has brought about the search for a better treatment. Microbial cellulose has shown promising results that avoid these disadvantages. The aim of this study was therefore to compare microbial cellulose with silver sulphadiazine as a dressing for partial thickness burns.MethodAll patients who presented with partial thickness (superficial and deep dermal) burns from October 2014 to October 2016 were screened for this randomised clinical trial. Twenty patients were included in each group: the cellulose group was treated with microbial cellulose sheets and the control group with silver sulphadiazine cream 10 mg/g. The wound was evaluated every third day. Pain was assessed using the Face, Legs, Activity, Cry, Consolability (FLACC) scale during and after each procedure. Other variables recorded were age, sex, percentage total body surface area burned (TBSA%), clinical signs of infection, time for epithelialisation and hospital stay. Linear multivariable regression was used to analyse the significance of differences between the treatment groups by adjusting for the size and depth of the burn, and the patient’s age.ResultsMedian TBSA% was 9% (IQR 5.5–12.5). The median number of dressing changes was 1 (IQR 1–2) in the cellulose group, which was lower than that in the control group (median 9.5, IQR 6–16) (p < 0.001). Multivariable regression analysis showed that the group treated with microbial cellulose spent 6.3 (95% CI 0.2–12.5) fewer days in hospital (p = 0.04), had a mean score that was 3.4 (95% CI 2.5–4.3) points lower during wound care (p < 0.001), and 2.2 (95% CI 1.6–2.7) afterwards (p < 0.001). Epithelialisation was quicker, but not significantly so.ConclusionThese results suggest that the microbial cellulose dressing is a better first choice for treatment of partial thickness burns than silver sulphadiazine cream. Fewer dressings of the wound were done and, combined with the low pain scores, this is good for both the patients and the health care system. The differences in randomisation of the area of burns is, however, a concern that needs to be included in the interpretation of the results.
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23.
  • Ayyer, Kartik, et al. (författare)
  • 3D diffractive imaging of nanoparticle ensembles using an x-ray laser
  • 2021
  • Ingår i: Optica. - : Optical Society of America. - 2334-2536. ; 8:1, s. 15-23
  • Tidskriftsartikel (refereegranskat)abstract
    • Single particle imaging at x-ray free electron lasers (XFELs) has the potential to determine the structure and dynamics of single biomolecules at room temperature. Two major hurdles have prevented this potential from being reached, namely, the collection of sufficient high-quality diffraction patterns and robust computational purification to overcome structural heterogeneity. We report the breaking of both of these barriers using gold nanoparticle test samples, recording around 10 million diffraction patterns at the European XFEL and structurally and orientationally sorting the patterns to obtain better than 3-nm-resolution 3D reconstructions for each of four samples. With these new developments, integrating advancements in x-ray sources, fast-framing detectors, efficient sample delivery, and data analysis algorithms, we illuminate the path towards sub-nano meter biomolecular imaging. The methods developed here can also be extended to characterize ensembles that are inherently diverse to obtain their full structural landscape. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License.
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24.
  • Beyerlein, Kenneth R., et al. (författare)
  • Mix-and-diffuse serial synchrotron crystallography
  • 2017
  • Ingår i: IUCrJ. - : INT UNION CRYSTALLOGRAPHY. - 2052-2525. ; 4:6, s. 769-777
  • Tidskriftsartikel (refereegranskat)abstract
    • Unravelling the interaction of biological macromolecules with ligands and substrates at high spatial and temporal resolution remains a major challenge in structural biology. The development of serial crystallography methods at X-ray free-electron lasers and subsequently at synchrotron light sources allows new approaches to tackle this challenge. Here, a new polyimide tape drive designed for mix-and-diffuse serial crystallography experiments is reported. The structure of lysozyme bound by the competitive inhibitor chitotriose was determined using this device in combination with microfluidic mixers. The electron densities obtained from mixing times of 2 and 50 s show clear binding of chitotriose to the enzyme at a high level of detail. The success of this approach shows the potential for high-throughput drug screening and even structural enzymology on short timescales at bright synchrotron light sources.
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25.
  • Costa, Tiago R. D., et al. (författare)
  • Active type III translocon assemblies that attenuate Yersinia virulence
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • Type III secretion enables bacteria to intoxicate eukaryotic cells with anti-host effectors. A class of secreted cargo are the two hydrophobic translocators that form a translocon pore in the host cell plasma membrane through which the translocated effectors may gain cellular entry. In pathogenic Yersinia, YopB and YopD shape this translocon pore. Here, four in cis yopD mutations were constructed to disrupt a predicted a-helix motif at the C-terminus. Mutants YopDI262P and YopDK267P poorly localised Yop effectors into target eukaryotic cells and failed to resist uptake and killing by immune cells. These defects were due to deficiencies in host-membrane insertion of the YopD-YopB translocon. Mutants YopDA263P and YopDA270P had no measurable in vitro translocation defect, even though they formed smaller translocon pores in erythrocyte membranes. Despite this, all four mutants were attenuated in a mouse infection model. Hence, YopD variants have been generated that can spawn translocons capable of targeting effectors in vitro, yet were bereft of any lethal effect in vivo. It is therefore probable that an active translocon makes a range of contributions during bacteria-host cell contact that extends beyond effector delivery per se.
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26.
  • Daurer, Benedikt J., et al. (författare)
  • Experimental strategies for imaging bioparticles with femtosecond hard X-ray pulses
  • 2017
  • Ingår i: IUCrJ. - : INT UNION CRYSTALLOGRAPHY. - 2052-2525. ; 4, s. 251-262
  • Tidskriftsartikel (refereegranskat)abstract
    • This study explores the capabilities of the Coherent X-ray Imaging Instrument at the Linac Coherent Light Source to image small biological samples. The weak signal from small samples puts a significant demand on the experiment. Aerosolized Omono River virus particles of similar to 40 nm in diameter were injected into the submicrometre X-ray focus at a reduced pressure. Diffraction patterns were recorded on two area detectors. The statistical nature of the measurements from many individual particles provided information about the intensity profile of the X-ray beam, phase variations in the wavefront and the size distribution of the injected particles. The results point to a wider than expected size distribution (from similar to 35 to similar to 300 nm in diameter). This is likely to be owing to nonvolatile contaminants from larger droplets during aerosolization and droplet evaporation. The results suggest that the concentration of nonvolatile contaminants and the ratio between the volumes of the initial droplet and the sample particles is critical in such studies. The maximum beam intensity in the focus was found to be 1.9 * 10(12) photons per mu m(2) per pulse. The full-width of the focus at half-maximum was estimated to be 500 nm (assuming 20% beamline transmission), and this width is larger than expected. Under these conditions, the diffraction signal from a sample-sized particle remained above the average background to a resolution of 4.25 nm. The results suggest that reducing the size of the initial droplets during aerosolization is necessary to bring small particles into the scope of detailed structural studies with X-ray lasers.
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27.
  • Din, Salah Ud, et al. (författare)
  • The Purification and Characterization of a Cutinase-like Enzyme with Activity on Polyethylene Terephthalate (PET) from a Newly Isolated Bacterium Stenotrophomonas maltophilia PRS8 at a Mesophilic Temperature
  • 2023
  • Ingår i: Applied Sciences (Switzerland). - : MDPI AG. - 2076-3417. ; 13:6
  • Tidskriftsartikel (refereegranskat)abstract
    • A polyethylene terephthalate (PET)-degrading bacterium identified as Stenotrophomonas maltophilia PRS8 was isolated from the soil of a landfill. The degradation of the PET bottle flakes and the PET prepared as a powder were assessed using live cells, an extracellular medium, or a purified cutinase-like enzyme. These treated polymers were analyzed using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The depolymerization products, identified using HPLC and LC-MS, were terephthalic acid (TPA), mono(2-hydroxyethyl)-TPA (MHET), and bis(2-hydroxyethyl)-TPA (BHET). Several physicochemical factors were optimized for a better cutinase-like enzyme production by using unique single-factor and multi-factor statistical models (the Plackett–Burman design and the central composite design software). The enzyme was purified for homogeneity through column chromatography using Sephadex G-100 resin. The molecular weight of the enzyme was approximately 58 kDa. The specific activity on para nitrophenyl butyrate was estimated at 450.58 U/mg, with a purification of 6.39 times and a yield of 48.64%. The enzyme was stable at various temperatures (30–40 °C) and pH levels (8.0–10.0). The enzyme activity was significantly improved by the surfactants (Triton X-100 and Tween-40), organic solvent (formaldehyde), and metals (NiCl2 and Na2SO4). The extracellular medium containing the cutinase-type enzyme showed a depolymerization yield of the PET powder comparable to that of Idonella skaiensis IsPETase and significantly higher than that of Humicola insolens thermostable HiCut (HiC) cutinase. This study suggests that S. maltophilia PRS8 is able to degrade PET at a mesophilic temperature and could be further explored for the sustainable management of plastic waste.
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28.
  • Efferth, Thomas, et al. (författare)
  • Biopiracy versus One-World Medicine-From colonial relicts to global collaborative concepts
  • 2019
  • Ingår i: Phytomedicine. - : Elsevier. - 0944-7113 .- 1618-095X. ; 53, s. 319-331
  • Forskningsöversikt (refereegranskat)abstract
    • Background: Practices of biopiracy to use genetic resources and indigenous knowledge by Western companies without benefit-sharing of those, who generated the traditional knowledge, can be understood as form of neo-colonialism. Hypothesis: The One-World Medicine concept attempts to merge the best of traditional medicine from developing countries and conventional Western medicine for the sake of patients around the globe. Study design: Based on literature searches in several databases, a concept paper has been written. Legislative initiatives of the United Nations culminated in the Nagoya protocol aim to protect traditional knowledge and regulate benefit-sharing with indigenous communities. The European community adopted the Nagoya protocol, and the corresponding regulations will be implemented into national legislation among the member states. Despite pleasing progress, infrastructural problems of the health care systems in developing countries still remain. Current approaches to secure primary health care offer only fragmentary solutions at best. Conventional medicine from industrialized countries cannot be afforded by the impoverished population in the Third World. Confronted with exploding costs, even health systems in Western countries are endangered to burst. Complementary and alternative medicine (CAM) is popular among the general public in industrialized countries, although the efficacy is not sufficiently proven according to the standards of evidence-based medicine. CAM is often available without prescription as over-the-counter products with non-calculated risks concerning erroneous self-medication and safety/toxicity issues. The concept of integrative medicine attempts to combine holistic CAM approaches with evidence-based principles of conventional medicine. Conclusion: To realize the concept of One-World Medicine, a number of standards have to be set to assure safety, efficacy and applicability of traditional medicine, e.g. sustainable production and quality control of herbal products, performance of placebo-controlled, double-blind, randomized clinical trials, phytovigilance, as well as education of health professionals and patients.
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29.
  • Elseify, Mohamed A., et al. (författare)
  • Single and multi-objectives based on an improved golden jackal optimization algorithm for simultaneous integration of multiple capacitors and multi-type DGs in distribution systems
  • 2024
  • Ingår i: Applied Energy. - : ELSEVIER SCI LTD. - 0306-2619 .- 1872-9118. ; 353
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper proposes a novel placement technique based on the improved golden jackal optimization (IGJO) algorithm for multiple capacitor banks (CBs) and multi-type DGs in a distribution network considering single and multi-objective problems. The proposed algorithm incorporates memory-based equations and random walk strategy to enhance the performance of the recent golden jackal optimization in terms of accuracy and convergence speed. The optimization problem is formulated as a weighted multi-objective that seeks to enhance the voltage profiles, boost stability, and minimize the total active power loss. An index named reactive loss sensitivity (QLSI) is also employed with the developed IGJO to identify the candidate nodes for the DGs and CBs installation to reduce the search space of the optimization algorithm. The robustness of the developed IGJO algorithm is evaluated through the CEC 2020 benchmark functions, and a comparison study is conducted with the original GJO and the other nine fresh competitors using various statistical tests to confirm its dominance and superiority. Then, the proposed IGJO is implemented in single and multi-objectives for the optimal deployment of multiple CBs individually and simultaneously with multiple DGs with different operating modes to enhance the performance of the IEEE 69-bus radial distribution system (RDS). The fetched outcomes are compared with the original GJO, weevil optimizer algorithm (WeevilOA), skill optimization algorithm (SOA), and Tasmanian devil optimization (TDO) to further measure its efficacy using different statistical tests. The IGJO algorithm is also applied to deploy multiple DGs for the IEEE 118-bus RDS with the aim of minimizing active loss. The simulation findings affirmed that the proposed IGJO technique beats the other rivals in all investigated situations, qualifying for the optimal inclusion of DGs in the presence of generation and demand uncertainties. Specifically, the integration of three units of CBs synchronously with three DGs Type-I and DG Type-III reduces
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30.
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31.
  • Fusai, Giuseppe Kito, et al. (författare)
  • Pancreatic surgery outcomes: multicentre prospective snapshot study in 67 countries
  • 2023
  • Ingår i: British Journal of Surgery. - : OXFORD UNIV PRESS. - 0007-1323 .- 1365-2168.
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Pancreatic surgery remains associated with high morbidity rates. Although postoperative mortality appears to have improved with specialization, the outcomes reported in the literature reflect the activity of highly specialized centres. The aim of this study was to evaluate the outcomes following pancreatic surgery worldwide. Methods: This was an international, prospective, multicentre, cross-sectional snapshot study of consecutive patients undergoing pancreatic operations worldwide in a 3-month interval in 2021. The primary outcome was postoperative mortality within 90 days of surgery. Multivariable logistic regression was used to explore relationships with Human Development Index (HDI) and other parameters. Results: A total of 4223 patients from 67 countries were analysed. A complication of any severity was detected in 68.7 percent of patients (2901 of 4223). Major complication rates (Clavien-Dindo grade at least IIIa) were 24, 18, and 27 percent, and mortality rates were 10, 5, and 5 per cent in low-to-middle-, high-, and very high-HDI countries respectively. The 90-day postoperative mortality rate was 5.4 per cent (229 of 4223) overall, but was significantly higher in the low-to-middle-HDI group (adjusted OR 2.88, 95 per cent c.i. 1.80 to 4.48). The overall failure-to-rescue rate was 21 percent; however, it was 41 per cent in low-to-middle-compared with 19 per cent in very high-HDI countries. Conclusion: Excess mortality in low-to-middle-HDI countries could be attributable to failure to rescue of patients from severe complications. The authors call for a collaborative response from international and regional associations of pancreatic surgeons to address management related to death from postoperative complications to tackle the global disparities in the outcomes of pancreatic surgery (NCT04652271; ISRCTN95140761).
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32.
  • Prasciolu, Mauro, et al. (författare)
  • On the use of multilayer Laue lenses with X-ray free electron lasers
  • 2021
  • Ingår i: International Conference on X-Ray Lasers 2020. - : SPIE. - 0277-786X .- 1996-756X. - 9781510646186 ; 11886
  • Konferensbidrag (refereegranskat)abstract
    • We report on the use of multilayer Laue lenses to focus the intense X-ray Free Electron Laser (XFEL) beam at the European XFEL to a spot size of a few tens of nanometers. We present the procedure to align and characterize these lenses and discuss challenges working with the pulse trains from this unique X-ray source.
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33.
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34.
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35.
  • Zhuang, Yulong, et al. (författare)
  • Unsupervised learning approaches to characterizing heterogeneous samples using X-ray single-particle imaging
  • 2022
  • Ingår i: IUCrJ. - : International Union of Crystallography (IUCr). - 2052-2525. ; 9, s. 204-214
  • Tidskriftsartikel (refereegranskat)abstract
    • One of the outstanding analytical problems in X-ray single-particle imaging (SPI) is the classification of structural heterogeneity, which is especially difficult given the low signal-to-noise ratios of individual patterns and the fact that even identical objects can yield patterns that vary greatly when orientation is taken into consideration. Proposed here are two methods which explicitly account for this orientation-induced variation and can robustly determine the structural landscape of a sample ensemble. The first, termed common-line principal component analysis (PCA), provides a rough classification which is essentially parameter free and can be run automatically on any SPI dataset. The second method, utilizing variation auto-encoders (VAEs), can generate 3D structures of the objects at any point in the structural landscape. Both these methods are implemented in combination with the noise-tolerant expand-maximizecompress (EMC) algorithm and its utility is demonstrated by applying it to an experimental dataset from gold nanoparticles with only a few thousand photons per pattern. Both discrete structural classes and continuous deformations are recovered. These developments diverge from previous approaches of extracting reproducible subsets of patterns from a dataset and open up the possibility of moving beyond the study of homogeneous sample sets to addressing open questions on topics such as nanocrystal growth and dynamics, as well as phase transitions which have not been externally triggered.
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36.
  • Ababneh, Nidaa A., et al. (författare)
  • Identification of APTX disease-causing mutation in two unrelated Jordanian families with cerebellar ataxia and sensitivity to DNA damaging agents
  • 2020
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15:8
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Ataxia with oculomotor apraxia type 1 (AOA1) is a rare autosomal recessive cerebellar ataxia, caused by mutations in the APTX gene. The disease is characterized by early-onset cerebellar ataxia, oculomotor apraxia and severe axonal polyneuropathy. The aim of this study was to detect the disease-causing variants in two unrelated consanguineous Jordanian families with cerebellar ataxia using whole exome sequencing (WES), and to correlate the identified mutation(s) with the clinical and cellular phenotypes. METHODS: WES was performed in three affected individuals and segregation analysis of p.W279* APTX candidate variant was performed. Expression levels of APTX were measured in patients' skin fibroblasts and peripheral blood mononuclear cells, followed by western blot analysis in skin fibroblasts. Genotoxicity assay was performed to detect the sensitivity of APTX mutated cells to H2O2, MMC, MMS and etoposide. RESULTS: A recurrent homozygous nonsense variant in APTX gene (c.837G>A, p.W279*) was revealed in all affected individuals. qRT-PCR showed normal APTX levels in peripheral blood and lower levels in fibroblast cells. However, western blot showed the absence of APTX protein in patients' skin fibroblasts. Significant hypersensitivity to H2O2, MMC and etoposide and lack of sensitivity to MMS were noted. CONCLUSIONS: This is the first study to report the identification of a nonsense variant in the APTX gene (c.837G>A; p.W279*) in AOA1 patients within the Jordanian population. This study confirmed the need of WES to assist in the diagnosis of cerebellar ataxia and it emphasizes the importance of studying the pathophysiology of the APTX gene.
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37.
  • Al-Ali, Fatima, et al. (författare)
  • Attitudes Towards Artificial Intelligence Among Dermatologists Working in Saudi Arabia.
  • 2023
  • Ingår i: Dermatology practical & conceptual. - : Mattioli1885. - 2160-9381. ; 13:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Artificial intelligence (AI) and its applications are among the most discussed modern technologies today. Despite the rapidly expanding use of AI in medicine, and specifically in dermatology, only a few studies have studied the attitude of physicians toward AI.To recognize the attitudes towards AI among dermatologists in the Kingdom of Saudi Arabia.A cross-sectional survey was done among dermatologists in Saudi Arabia. Questionnaires were distributed through several online channels.Overall, 103 dermatologists filled out the survey. The majority saw very strong or strong potential for AI in the automated detection of skin diseases based on dermatological clinical images (50.9%), dermoscopic images (66.6%) and within dermatopathology (66.6%). In regard to results of attitudes towards AI, 56.6% and 52. 8% agreed that AI will revolutionize medicine and dermatology, respectively. However, many of the respondents disagreed that AI will replace physicians (41.5%) and human dermatologists (39.6%) in the future. Age did not impact the overall attitude of dermatologists.Dermatologists in Saudi Arabia showed an optimistic attitude towards AI in dermatology and medicine. However, dermatologists believe that AI will not replace humans in the future.
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38.
  • Alawsi, Mustafa A., et al. (författare)
  • Drought Forecasting: A Review and Assessment of the Hybrid Techniques and Data Pre-Processing
  • 2022
  • Ingår i: Hydrology. - : MDPI. - 2306-5338. ; 9:7
  • Forskningsöversikt (refereegranskat)abstract
    • Drought is a prolonged period of low precipitation that negatively impacts agriculture, animals, and people. Over the last decades, gradual changes in drought indices have been observed. Therefore, understanding and forecasting drought is essential to avoid its economic impacts and appropriate water resource planning and management. This paper presents a recent literature review, including a brief description of data pre-processing, data-driven modelling strategies (i.e., univariate or multivariate), machine learning algorithms (i.e., advantages and disadvantages), hybrid models, and performance metrics. Combining various prediction methods to create efficient hybrid models has become the most popular use in recent years. Accordingly, hybrid models have been increasingly used for predicting drought. As such, these models will be extensively reviewed, including preprocessing-based hybrid models, parameter optimisation-based hybrid models, and hybridisation of components combination-based with preprocessing-based hybrid models. In addition, using statistical criteria, such as RMSE, MAE, NSE, MPE, SI, BIC, AIC, and AAD, is essential to evaluate the performance of the models.
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39.
  • Alawsi, Mustafa A., et al. (författare)
  • Tuning ANN Hyperparameters by CPSOCGSA, MPA, and SMA for Short-Term SPI Drought Forecasting
  • 2022
  • Ingår i: Atmosphere. - : MDPI. - 2073-4433. ; 13:9
  • Tidskriftsartikel (refereegranskat)abstract
    • Modelling drought is vital to water resources management, particularly in arid areas, to reduce its effects. Drought severity and frequency are significantly influenced by climate change. In this study, a novel hybrid methodology was built, data preprocessing and artificial neural network (ANN) combined with the constriction coefficient-based particle swarm optimisation and chaotic gravitational search algorithm (CPSOCGSA), to forecast standard precipitation index (SPI) based on climatic factors. Additionally, the marine predators algorithm (MPA) and the slime mould algorithm (SMA) were used to validate the performance of the CPSOCGSA algorithm. Climatic factors data from 1990 to 2020 were employed to create and evaluate the SPI 1, SPI 3, and SPI 6 models for Al-Kut City, Iraq. The results indicated that data preprocessing methods improve data quality and find the best predictors scenario. The performance of CPSOCGSA-ANN is better than MPA-ANN and SMA-ANN algorithms based on various statistical criteria (i.e., R2, MAE, and RMSE). The proposed methodology yield R2 = 0.93, 0.93, and 0.88 for SPI 1, SPI 3, and SPI 6, respectively.
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40.
  • Ali, Hala R., et al. (författare)
  • Effects of macrophage polarization on gold nanoparticle-assisted plasmonic photothermal therapy
  • 2021
  • Ingår i: RSC Advances. - : Royal Society of Chemistry. - 2046-2069. ; 11:40, s. 25047-25056
  • Tidskriftsartikel (refereegranskat)abstract
    • Tumor associated macrophages (TAM) are key pathogenic factors in neoplastic diseases. They are known to have plasticity and can polarize into two opposing phenotypes, including the tumoricidal M1 and the protumoral M2 phenotypes with high prevalence of M2-phentoypes in patients with poor prognosis. Strategies for targeting M2-TAM may consequently increase the efficacy of therapeutic strategies for cancer treatment. Gold nanorod-assisted plasmonic photothermal therapy (PPTT) has emerged as a promising treatment for cancer but the effects of macrophage polarization parameters in the performance of this new treatment modality is still unknown. Herein, human monocytic THP-1 cells were polarized into two opposite phenotypic macrophages (M1-TAM and M2-TAM) and their response to PPTT was examined. M2-TAM exhibits a three-fold increase in AuNP uptake compared to M1-TAM. Laser irradiation results in selective killing of pro-tumoral M2-TAM after treatment with AuNPs with limited effects on anti-tumoral M1-TAM. A positive correlation between the expression of CD206 marker and the AuNP uptake may indicate the role of CD206 in facilitating AuNP uptake. Our findings also suggest that the differences in AuNP avidity and uptake between the M1-TAM and M2-TAM phenotypes may be the rationale behind the effectiveness of PPTT in the treatment of solid tumors.
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41.
  • Ali, Magdi M. M., et al. (författare)
  • Fc gamma RIIa (CD32) polymorphism and onchocercal skin disease : implications for the development of severe reactive onchodermatitis (ROD)
  • 2007
  • Ingår i: American Journal of Tropical Medicine and Hygiene. - Lawrence, Kans. : American society of tropical medicine and hygiene. - 0002-9637 .- 1476-1645. ; 77:6, s. 1074-8
  • Tidskriftsartikel (refereegranskat)abstract
    • The pathologic manifestations of Onchocerca volvulus infection depend on the interplay between the host and the parasite. A genetic single nucleotide polymorphism in the Fc gamma RIIa gene, resulting in arginine (R) or histidine (H) at position 131, affects the binding to the different IgG subclasses and may influence the clinical variations seen in onchocerciasis. This study investigated the relationship between this polymorphism and disease outcome. Fc gamma RIIa genotyping was performed on clinically characterized onchocerciasis patients (N = 100) and healthy controls (N = 74). Fc gamma RIIa genotype R/R131 frequencies were significantly higher among patients with severe dermatopathology (P < 0.001). Increased risk of developing this form was mostly associated with one tribe (Masalit) (OR = 3.2, 95% CI 1-9.9, P = 0.042). The H131 allele was found to be significantly associated with a reduced risk of having the severe form of the disease (adjusted OR = 0.26, 95% CI = 0.13-0.46, P < 0.001). Our findings suggest that the polymorphism influences the clinical outcome of onchocerciasis.
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42.
  • Alsharaeh, E. H., et al. (författare)
  • Sol-Gel-Assisted Microwave-Derived Synthesis of Anatase Ag/TiO2/GO Nanohybrids toward Efficient Visible Light Phenol Degradation
  • 2017
  • Ingår i: Catalysts. - : MDPI AG. - 2073-4344. ; 7:5
  • Tidskriftsartikel (refereegranskat)abstract
    • A simple microwave-assisted (MWI) wet chemical route to synthesize pure anatase phase titanium dioxide (TiO2) nanoparticles (NPs) is reported here using titanium tetrachloride (TiCl4) as starting material. The as-prepared TiO2 NPs were characterized by electron microscopy, X-ray diffraction, UV/visible absorption spectroscopy, and infrared and Raman spectroscopic techniques. Further modification of the anatase TiO2 NPs was carried out by incorporating plasmonic silver (Ag) NPs and graphene oxide (GO) in order to enhance the visible light absorption. The photocatalytic activities of the anatase TiO2, Ag/TiO2, and Ag/TiO2/GO nanocomposites were evaluated under both ultraviolet (UV) and visible light irradiation using phenol as a model contaminant. The presence of Ag NPs was found to play a significant role to define the photocatalytic activity of the Ag/TiO2/GO nanocomposite. It was found that the Ag performed like a sink under UV excitation and stored photo-generated electrons from TiO2, whereas, under visible light excitation, the Ag acted as a photosensitizer enhancing the photocatalytic activity of the nanocomposite. The detailed mechanism was studied based on photocatalytic activities of Ag/TiO2/GO nanocomposites. Therefore, the as-prepared Ag/TiO2/GO nanocomposite was used as photocatalytic materials under both UV and visible light irradiation toward degradation of organic molecules.
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43.
  • Balogun, Halima A., et al. (författare)
  • Pf332-C231-reactive antibodies affect growth and development of intra-erythrocytic Plasmodium falciparum parasites
  • 2011
  • Ingår i: Vaccine. - : Elsevier BV. - 0264-410X .- 1873-2518. ; 30:1, s. 21-28
  • Tidskriftsartikel (refereegranskat)abstract
    • The Plasmodium falciparum antigen 332 (Pf332), is a megadalton parasite protein expressed at the surface of infected red cells during later stages of the parasite's developmental cycle. Antibodies to different parts of this antigen have been shown to inhibit parasite growth and adherence to host cells with or without ancillary cells. However, the mechanisms involved in these inhibitions remain largely unknown. We further analysed the activities of specific antibodies with regard to their specific mechanisms of action. For these analyses, affinity purified human antibodies against epitopes in the C-terminal fragment of Pf332 (Pf332-C231) were employed. All purified antibodies recognized Pf332-C231 both by immunofluorescence and ELISA. IgG was the main antibody isotype detected, although all sera investigated had varying proportions of IgG and IgM content. All the antibodies showed a capacity to inhibit parasite growth in P. falciparum cultures to different extents, mainly by acting on the more mature parasite stages. Morphological analysis revealed the antibody effects to be characterized by the presence of a high proportion of abnormal schizonts (15-30%) and pyknotic parasites. There was also an apparent antibody effect on the red cell integrity, as many developing parasites (up to 10% of trophozoites and schizonts) were extracellular. In some cases, the infected red cells appeared to be disintegrating/fading, staining paler than surrounding infected and uninfected cells. Antigen reversal of inhibition confirmed that these inhibitions were antigen specific. Furthermore, the growth of parasites after 22-42 h exposure to antibodies was investigated. Following the removal of antibody pressure, a decreased growth rate of these parasites was seen compared to that of control parasites. The present study confirms the potential of Pf332 as a target antigen for parasite neutralizing antibodies, and further indicates that epitopes within the C231 region of Pf332 should constitute important tools in the dissection of the role of Pf332 in the biology of the malaria parasite, as well as in the design of a malaria vaccine.
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44.
  • Ebeed, Mohamed, et al. (författare)
  • A Modified Artificial Hummingbird Algorithm for solving optimal power flow problem in power systems
  • 2024
  • Ingår i: Energy Reports. - : ELSEVIER. - 2352-4847. ; 11, s. 982-1005
  • Tidskriftsartikel (refereegranskat)abstract
    • Optimal power flow (OPF) problem solution is a crucial task for the operators and decision makers to assign the best setting of the system components to obtain the most economic, environmental, and technical suitable state. Artificial Hummingbird Algorithm is a recent optimization algorithm that has been applied to solving several optimization problems. In this paper, a Modified Artificial Hummingbird Algorithm (MAHA) is proposed for improving the performance of the orignal Artificial Hummingbird Algorithm as well as effectivelly solve the OPF problem. The proposed MAHA is based on improving the searching capability by boosting the exploitation using the bandwidth motion around the best solution, while the exploration process is improved using the Levy flight distribution motion and the fitness-distance balance selection. This modified version helps overcome issues such as stagnation, premature convergence, and a propensity for local optima when tackling complex, nonlinear, and non-convex optimization problems like OPF. In order to confirm the effectiveness of the proposed algorithm, a series of tests are conducted on 23 standard benchmark functions, including CEC2020. The resulting outcomes are then compared to those obtained using other algorithms such as fitness-distance balance selection-based stochastic fractal search (FDBSFS), antlion optimizer (ALO), whale optimization algorithm (WOA), sine-cosine algorithm (SCA), fitness-distance balance and learning based artificial bee colony (FDB-TLABC), and traditional artificial hummingbird algorithm (AHA).The proposed algorithm is evaluated by solving the OPF problem with multiple objective functions on the IEEE 30-bus system. These objectives include fuel cost, fuel cost with valve loading effects, power losses, emissions, and voltage profile. Additionally, the algorithm's effectiveness is further assessed by testing it on single objective functions using medium and large-scale IEEE 57 and 118-bus networks.The results obtained by the proposed MAHA demonstrate its power and superiority for solving the OPF problem as well as the standard benchmark functions , surpassing the performance of other reported techniques.
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45.
  • Ebeed, Mohamed, et al. (författare)
  • Solving stochastic optimal reactive power dispatch using an Adaptive Beluga Whale optimization considering uncertainties of renewable energy resources and the load growth
  • 2024
  • Ingår i: Ain Shams Engineering Journal. - : ELSEVIER. - 2090-4479 .- 2090-4495. ; 15:7
  • Tidskriftsartikel (refereegranskat)abstract
    • The electrical system performance can be improved considerably by controlling the reactive power flow in the system. The reactive power control can be achieved by optimal reactive power dispatch (ORPD) problem solution and optimal integration of the FACTS devices. With high penetration of renewable energy sources (RESs) and the load growth, the ORPD solution became a challenging and a complex task due to the stochastic nature of the RERs and the load growth. In this regard, the aim of this paper is to solve the stochastic optimal reactive power dispatch (SORPD) with optimal inclusion of PV units, wind turbines and the unified power flow controller (UPFC) under uncertainties of the load growth and the generated powers. An Adaptive Beluga Whale Optimization (ABWO) is proposed for solving the SORPD which is based on the Fitness-Distance Balance Selection (FDBS) strategy and the territorial solitary males' strategy of the Mountain Gazelle Optimizer. The proposed ABWO is tested on IEEE 30-bus system and a comparison with other optimization techniques for solving the ordinary ORPD is presented for validating the proposed ABWO. The obtained results reveal that the TEPL is reduced from 5.3168 MW to 3.97985 MW with optimal integration of the RERs and UPFC. Likewise, the TEVD is reduced from 0.1794p.u. to 0.10689p.u. and the TVSI is decreased from 0.1289p.u. to 0.0476p.u.
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46.
  • El Amin, Seif, et al. (författare)
  • Introducing qualitative perinatal audit in a tertiary hospital in Sudan
  • 2002
  • Ingår i: Health Policy and Planning. - 0268-1080 .- 1460-2237. ; 17:3, s. 296-303
  • Tidskriftsartikel (refereegranskat)abstract
    • In a 3-month period, May to August 2000, the perinatal mortality rate at Omdurman Maternity Hospital (OMH), Sudan, was 8.2%. Two groups of perinatal deaths, intrapartum deaths of non-malformed infants and neonatal deaths of mature infants above 34 weeks, both considered to be potentially avoidable by improved care, were in excess when compared with other regions. It was therefore decided to perform in-depth assessment of cases in these two groups. An interdisciplinary internal audit was designed in collaboration with two external obstetricians. The audit activity was preceded by a 2-day workshop at the hospital. Individual assessments based on 43 detailed narratives were followed by regular consensus meetings. This structure seemed useful for interdisciplinary discussions, and the audit process resulted in several specific suggestions for quality improvement in data collection, interdisciplinary collaboration, and obstetric and neonatal care. The present audit activity is not very resource demanding and therefore a good starting point for quality assurance in a developing country. However, since adverse outcome audit only focuses on selected cases and may encourage interventions without considering the full impact on the population, it should not stand alone. Audit of perinatal deaths should be combined with other quantitative and qualitative quality assessment activities for improvement of perinatal care.
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47.
  • Hess, Timo, et al. (författare)
  • Dissecting the genetic heterogeneity of gastric cancer
  • 2023
  • Ingår i: EBioMedicine. - : Elsevier. - 2352-3964. ; 92
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Gastric cancer (GC) is clinically heterogenous according to location (cardia/non-cardia) and histopathology (diffuse/intestinal). We aimed to characterize the genetic risk architecture of GC according to its subtypes. Another aim was to examine whether cardia GC and oesophageal adenocarcinoma (OAC) and its precursor lesion Barrett's oesophagus (BO), which are all located at the gastro-oesophageal junction (GOJ), share polygenic risk architecture.Methods: We did a meta-analysis of ten European genome-wide association studies (GWAS) of GC and its subtypes. All patients had a histopathologically confirmed diagnosis of gastric adenocarcinoma. For the identification of risk genes among GWAS loci we did a transcriptome-wide association study (TWAS) and expression quantitative trait locus (eQTL) study from gastric corpus and antrum mucosa. To test whether cardia GC and OAC/BO share genetic aetiology we also used a European GWAS sample with OAC/BO.Findings: Our GWAS consisting of 5816 patients and 10,999 controls highlights the genetic heterogeneity of GC according to its subtypes. We newly identified two and replicated five GC risk loci, all of them with subtype-specific association. The gastric transcriptome data consisting of 361 corpus and 342 antrum mucosa samples revealed that an upregulated expression of MUC1, ANKRD50, PTGER4, and PSCA are plausible GC-pathomechanisms at four GWAS loci. At another risk locus, we found that the blood-group 0 exerts protective effects for non-cardia and diffuse GC, while blood-group A increases risk for both GC subtypes. Furthermore, our GWAS on cardia GC and OAC/BO (10,279 patients, 16,527 controls) showed that both cancer entities share genetic aetiology at the polygenic level and identified two new risk loci on the single-marker level.Interpretation: Our findings show that the pathophysiology of GC is genetically heterogenous according to location and histopathology. Moreover, our findings point to common molecular mechanisms underlying cardia GC and OAC/BO. 
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48.
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49.
  • Hussien, Abdelazim, et al. (författare)
  • Enhancing optimal sizing of stand-alone hybrid systems with energy storage considering techno-economic criteria based on a modified artificial rabbits optimizer
  • 2024
  • Ingår i: Journal of Energy Storage. - : ELSEVIER. - 2352-152X .- 2352-1538. ; 78
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper examines and analyses a novel developed algorithm named Modified Artificial Rabbits Optimization (mARO), which is based on the modification of a bio-inspired meta-heuristic algorithm called Artificial Rabbits Optimization (ARO) combined with dimension learning-based hunting technique. In order to prove the efficiency and evaluate the constrained optimization of this modified algorithm mARO, it is applied to one of an engineering application. This engineering application is the study of the optimal sizing of a stand-alone hybrid system based on techno-economic criteria; this hybrid system consists of the PV, WT, Biomass system, and Battery units. The simulation of hybrid power systems must be carried out with the least amount of expense and harm to the environment so appropriate performance may be ensured using an efficient and optimal sizing strategy. In order to prove the superiority of this modified algorithm mARO, the results of this algorithm were compared with other new algorithms, and these algorithms are the original ARO, Dandelion Optimizer (DO), and Driving TrainingBased Optimization (DTOB).
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50.
  • Mallhi, Tauqeer Hussain, et al. (författare)
  • Incidence, risk factors and outcomes of acute kidney injury among COVID-19 patients : A systematic review of systematic reviews
  • 2022
  • Ingår i: Frontiers in Medicine. - : Frontiers Media S.A.. - 2296-858X. ; 9
  • Forskningsöversikt (refereegranskat)abstract
    • The COVID-19 associated acute kidney injury (CAKI) has emerged as a potential intricacy during the management of patients. Navigating the rapidly growing body of scientific literature on CAKI is challenging, and ongoing critical appraisal of this complication is essential. This study aimed to summarize and critically appraise the systematic reviews (SRs) on CAKI to inform the healthcare providers about its prevalence, risk factors and outcomes. All the SRs were searched in major databases (PubMed, EMBASE, Web of Science) from inception date to December 2021. This study followed SR of SRs methodology, all the records were screened, extracted and subjected to quality assessment by assessing the methodological quality of systematic reviews (AMSTAR-2). The extracted data were qualitatively synthesized and tabulated. This review protocol was registered in PROSPERO (CRD42022299444). Of 3,833 records identified; 42 SRs were included in this overview. The quality appraisal of the studies showed that 17 SRs were of low quality, while 8 moderate and 17 were of high-quality SRs. The incidence of CAKI ranged from 4.3% to 36.4% in overall COVID-19 patients, 36%-50% in kidney transplant recipients (KTRs), and up to 53% in severe or critical illness. Old age, male gender, cardiovascular disease, chronic kidney disease, diabetes mellitus and hypertension were frequently reported risk factors of CAKI. The need of renal replacement therapy (RRT) was up to 26.4% in overall COVID-19 patients, and 39% among those having CAKI. The occurrence of acute kidney injury (AKI) was found independent predictor of death, where mortality rate among CAKI patients ranged from 50% to 93%. This overview of SRs underscores that CAKI occurs frequently among COVID-19 patients and associated with high mortality, need of RRT and adverse outcomes. However, the confidence of these results is moderate to low which warrants the need of more SRs having established methodological standards.
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