The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an emergent infectious pathogen causing an acute respiratory disease called corona virus disease 2019 (COVID-19). Virus ...transmission may occur by contact, droplet, airborne or via contaminated surfaces. In efforts to effectively control the COVID-19 outbreak, the world health organization (WHO) and the Saudi Ministry of Health (MOH) have advised the public to practice protective measures to reduce transmission of the virus and reduce incidence of infection. These measures include hand washing, wearing masks and gloves and avoidance of touching the face with unwashed hands. The current study aimed to investigate knowledge and adherence of the Saudi population to these protective actions during the pandemic. After determining the required sample size using power analysis, a cross-sectional online self-reported survey of 5105 Saudi residents was conducted between 25th March to 17th April 2020 to evaluate public knowledge of COVID-19. Participants were all aged 18 years or above, Arabic speakers and residents of Saudi Arabia. Scores were calculated based on knowledge and adherence of the individuals to protective measures. About 90% of participants exhibited a high level of knowledge (scored 2/2) and practice (scored > 3/6) in relation to hand hygiene and wearing gloves and masks. Practice scores were positively associated with females and individuals with high income. Lower practice scores were linked to youth and residents of the northern and western regions of the Kingdom. Over two thirds of participants preferred hand washing to alcohol disinfection, and the frequency and performance of hand washing improved during the pandemic for more than half of respondents. Overall, the findings reflected high public knowledge of SARS-CoV2 transmission routes and adherence to personal protective measures. However, public awareness campaigns with an emphasis on the youth and individuals with low education and income are required to improve overall practice.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
For individuals with knee osteoarthritis (OA), stair negotiation is a challenging task and the first task during which they report pain due to the high knee loading required. The use of lateral wedge ...insole (LWI) has been found to reduce loading in patients with OA but not to reduce pain, whereas the use of knee sleeve has been shown to result in good pain reduction. Understanding the effect of combining LWI and knee sleeve use on healthy individuals before testing on individuals with knee OA is an important step.
The current study aimed to evaluate the effect of combining the use of LWI and knee sleeve and compare the results with the application of each treatment separately and with the control condition.
This randomised cross-over study included 17 healthy participants who underwent 3D gait analysis. Participants performed ascending and descending stair activities with the following four treatment conditions: five-degree LWI, off-the-shelf knee sleeve, both LWI and knee sleeve and control condition. External knee adduction moment (EKAM) and knee frontal plane range of motion (ROM) were evaluated as primary outcomes. Repeated measure ANOVA or the Friedman test was selected based on meeting the assumption followed by multiple pairwise comparisons with Bonferroni correction.
In general, the use of LWI reduced the first peak EKAM significantly (p < 0.001) compared to the control condition in stir ascending (12% reduction) but not in stair descending (p > 0.05). Interestingly, knee sleeve use did not result in any reduction in the first peak EKAM compared to the control or any other condition. However, knee sleeve use led to a significant reduction in the knee frontal plane ROM during stair descending. The combined treatment was not superior to the LWI use when compared to control in the EKAM reduction.
Combined knee sleeve and LWI use was not superior to LWI use alone in reducing the knee loading, but it may be beneficial for individuals with knee OA since it helped in reduction of the knee frontal plane ROM during stair descending. Importantly, the effect of LWI use or any other treatment must be investigated for each different activity, and the results found in one activity must not be generalised across other activities.
•Knee sleeve and LWI has not been combined in previous study during stair activities or walking.•LWI showed reduction in EKAM in general during stair ascending and descending.•Knee sleeve help to provide stability in frontal plan ROM during stair descending.
DNA methylation is a key epigenetic modification which, in mammals, occurs mainly at CpG dinucleotides. Most of the CpG methylation in the genome is found in repetitive regions, rich in dormant ...transposons and endogenous retroviruses. Global DNA hypomethylation, which is a common feature of several conditions such as ageing and cancer, can cause the undesirable activation of dormant repeat elements and lead to altered expression of associated genes. DNA hypomethylation can cause genomic instability and may contribute to mutations and chromosomal recombinations. Various approaches for quantification of global DNA methylation are widely used. Several of these approaches measure a surrogate for total genomic methyl cytosine and there is uncertainty about the comparability of these methods. Here we have applied 3 different approaches (luminometric methylation assay, pyrosequencing of the methylation status of the Alu repeat element and of the LINE1 repeat element) for estimating global DNA methylation in the same human cell and tissue samples and have compared these estimates with the "gold standard" of methyl cytosine quantification by HPLC. Next to HPLC, the LINE1 approach shows the smallest variation between samples, followed by Alu. Pearson correlations and Bland-Altman analyses confirmed that global DNA methylation estimates obtained via the LINE1 approach corresponded best with HPLC-based measurements. Although, we did not find compelling evidence that the gold standard measurement by HPLC could be substituted with confidence by any of the surrogate assays for detecting global DNA methylation investigated here, the LINE1 assay seems likely to be an acceptable surrogate in many cases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background. Musculoskeletal disorders (MSDs) are affecting up to 95% of teachers and are considered a primary occupational health hazard leading to absenteeism, early retirement, and lower quality of ...life and teaching quality. Aim. The current study is aimed at exploring the prevalence and risk factors of MSDs among the schoolteachers in Hail, Saudi Arabia. Methods. A cross-sectional study was conducted online among the teachers in Hail City using the Nordic Musculoskeletal Questionnaire. Teachers were randomly selected from randomly selected high schools. Teachers with at least 1 year experience were recruited for the study. Descriptive statistics, Cochran’s Q test, and binominal regression were used to investigate the prevalence of MSDs among such teachers and to determine if the percentage of MSDs differed by anatomical region and risk factor (one hundred forty-five males and 106 females filled out the questionnaires). Results. The prevalence of MSDs in the last 12 months was 93.63% (235 of 251 teachers). Interestingly, 91% of the affected participants (214 of 235 teachers) complained of MSDs in more than one anatomical region. The most affected site was the lower back (183 of 251 teachers, 72.91%), followed by the shoulders (168 of 251 teachers, 66.93%), and the least affected sites were the elbows (45 of 251 teachers, 17.93%). The females showed a higher prevalence of MSDs than the males. Only gender was a significant risk factor for shoulder and neck MSDs (p<0.02). Conclusion. Overall, the findings of the current study suggest a high prevalence of MSDs among teachers, especially in the lower back and shoulders. The affected teachers should learn more about biomechanics and ergonomics and should engage in exercise to improve their health. Future studies should focus on identifying the biomechanical and ergonomic risk factors of MSDs and on designing MSD prevention programmes to reduce the burden of MSDs.
In recent years the popularity of disabled sports and competition among disabled athletes has grown considerably. With this rise in exposure of, and participation in wheelchair sports comes an ...increase in related stressors, including musculoskeletal load. External mechanical loading may increase the risk of shoulder complaints. The objective of this literature review was to 1) identify and describe the prevalence and/or incidence of shoulder complaints in wheelchair athletes in the literature, to 2) examine the factors and underlying mechanisms that could be potentially involved, and 3) provide some insights into the development of preventative measures.
A literature search was conducted using PubMed, Scopus and Embase databases, to identify relevant published articles. All articles in the English language that contained any type of shoulder complaint in relation with a wheelchair sports player, at any level of status (recreational to elite), of any sport, were included. Articles were excluded if they did not include any statistical analysis. Articles that included studies with wheelchair athletes in combination with athletes of other disability sports were excluded in order to be able to differentiate between the two. Narrative, exploratory and case studies were also excluded. Two reviewers independently assessed articles for inclusion. Thirteen articles matched the selection criteria. These were judged on their quality by use of an adapted version of the Webster checklist.
Of the included studies the overall quality was low. A relatively high prevalence of complaints was found, ranging from 16% to 76%. Pain was found to be a common complaint in wheelchair athletes. Based on the current literature the cause of shoulder problems is difficult to identify and is likely multifactorial, nevertheless characteristics of the user (i.e. increased years of disability, age and BMI) were shown to increase risk. Preventative measures were indistinct. There may be a role for balanced strength training regimens to decrease risk.
Shoulder complaints in wheelchair athletes are a common problem that must be addressed further. Future studies on shoulder overuse injuries of wheelchair athletes should be directed towards biomechanical modeling to develop knowledge of load and its effects.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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•Ag doped flowerlike rutile-phase Ag-FR TiO2 film with exposed (110) and (111) facets.•The synergistic effects between (110) and (111) facets and Ag/self-doped Ti3+-oxygen.•The ...significance of electron trapping in photodegradation are explained in detail.•The Ag-FR TiO2 film with 1 wt% Ag showed the best performance of methylene blue degradation.
Ag-doped flowerlike rutile-phase (Ag-FR) TiO2 film with exposed (110) and (111) facet was fabricated by a facile hydrothermal method at 150 °C without additive or capping agent with different Ag content ranging from 0.5 to 2 wt%. This study investigated the influence of Ag content in enhancing the photocatalytic activity of Ag-FR TiO2 film. The flowerlike structures increased the active area of the TiO2 film. XPS revealed that the concentration of Ti3+-oxygen vacancy defects increased upon doping, while TEM revealed that the (110) and (111) are highly exposed facets of rods with flowerlike structure. The effectiveness of the Ag-FR TiO2 film was tested on methylene blue degradation under xenon lamp irradiation. The Ag-FR TiO2 film with 1 wt% Ag resulted in the highest methylene blue degradation, which was 20% higher than degradation by the undoped TiO2. The synergistic effect between both (110) and (111) facets and Ti3+-oxygen vacancy from Ag play an important role in reducing the band gap and acts as an electron trap. This suppresses recombination between electrons and holes to enhance the photocatalytic activity thus extending the lifetime of the photogenerated electron and hole.
A range of natural products have been extensively studied for their chemopreventive potential for cancer, including those that inhibit growth and induce apoptosis. Sidr honey derived from the
or
tree ...(
,
, or
) is used in a wide range of traditional medicine practices. In the current study, the Saudi Sidr honey was analyzed by means of a GC-MS chromatogram and investigated for its antiproliferative effects on colorectal cancer cells (HCT-116), breast cancer cells (MCF-7), and lung cancer cells (A-549), as well as its apoptosis induction and cell cycle arrest potentials against human colorectal cancer cells (HCT-116). The effects of Saudi Sidr honey on cells were determined using the MTT assay and the clonogenic assay. The induction of apoptosis was studied using Annexin V-FITC flow cytometry analysis. The propidium iodide staining method was used to detect cell cycle arrest via flow cytometry. By means of performing GS-MS and HR-LCMS analysis, 23 different chemical components were identified from Saudi Sidr honey. A dose-response analysis showed that Saudi Sidr honey was more effective against HCT-116 (IC
= 61.89 ± 1.89 µg/mL) than against MCF-7 (IC
= 78.79 ± 1.37 µg/mL) and A-549 (IC
= 94.99 ± 1.44 µg/mL). The antiproliferation activity of Saudi Sidr honey has been found to be linked to the aggregation of cells during the G1 phase, an increase in early and late apoptosis, and necrotic cell death in HCT-116 cells. Considering these promising findings that highlight the potential use of Saudi Sidr honey as an antitumor agent, further research should be carried out with the aim of isolating, characterizing, and evaluating the bioactive compounds involved in Sidr honey's antiproliferative activity to better understand the mechanism of their action.
Novel machine-learning and feature-selection algorithms have been developed to study:
i
) the flare-prediction-capability of magnetic feature (MF) properties generated by the recently developed
Solar ...Monitor Active Region Tracker
(SMART);
ii
) SMART’s MF properties that are most significantly related to flare occurrence. Spatiotemporal association algorithms are developed to associate MFs with flares from April 1996 to December 2010 in order to differentiate flaring and non-flaring MFs and enable the application of machine-learning and feature-selection algorithms. A machine-learning algorithm is applied to the associated datasets to determine the flare-prediction-capability of all 21 SMART MF properties. The prediction performance is assessed using standard forecast-verification measures and compared with the prediction measures of one of the standard technologies for flare-prediction that is also based on machine-learning:
Automated Solar Activity Prediction
(ASAP). The comparison shows that the combination of SMART MFs with machine-learning has the potential to achieve more accurate flare-prediction than ASAP. Feature-selection algorithms are then applied to determine the MF properties that are most related to flare occurrence. It is found that a reduced set of six MF properties can achieve a similar degree of prediction accuracy as the full set of 21 SMART MF properties.
This paper presents a fuzzy logic controller for a two-tank level control system, which is a process with a dead time. The fuzzy controller is a proportional-integral (PI-like) fuzzy controller which ...is suitable for steady state behavior of the system. Transient behavior of the system was improved without the need for a derivative action by suitable change in the rule base of the controller. Simulation results showed the step response of the two-tank level control system when this controller was used to control this plant and the effect of the dead time on the response of the system.
Bacterial coinfection among patients with confirmed coronavirus disease 2019 (COVID-19) is a critical medical concern that increases the disease severity and mortality rate. The current study is ...aimed at evaluating the effects of bacterial coinfections among COVID-19 patients, especially in relation to degree of severity and mortality. A retrospective study was conducted for patients with positive COVID-19 test, admitted to a regional COVID-19 hospital in Jeddah, Saudi Arabia, between May and August 2020. A specimen (e.g., blood, urine, or sputum) was collected from patients with confirmed COVID-19, and was cultured to determine bacterial coinfection caused by multidrug resistant (MDR) bacteria. COVID-19 patients were categorized into 2 groups based on the result of bacterial coinfection culture, as COVID-19 patients with coinfection and COVID-19 patients without coinfection. Independent sample t test or Mann-Whitney U test was used to compare age and hospitalization period between these groups. In addition, binominal logistic regression was applied to identify risk factors associated with mortality and bacterial coinfection. The study included 342 patients with laboratory confirmed COVID-19. Eighty (23.3%) patients were diagnosed with bacterial coinfection, while the remaining 262 (76.6%) patients did not test positive for bacterial coinfection. Length of hospital stay was prolonged among COVID-19 patients diagnosed with bacterial coinfection (16.01 ± 11.36 days) when compared with patients without bacterial coinfection (6.5 ± 6.12 days). Likewise, the mortality rate was significantly higher among COVID-19 patients with bacterial coinfection (90%) compared to those without bacterial coinfection (49.2%). Gram-negative bacteria were predominant compared to gram-positive, as Klebsiella pneumoniae (35 43.8%) and Acinetobacter baumanni (32 40%). On the other hand, Staphylococcus aureus (4 5%), Enterococcus faecalis (1 1.3%), and Enterococcus faecium (1 1.3%) were identified as gram-positive bacterial species from recruited patients. The findings of the current study showed that prolong hospitalization is the main risk factor associated with bacterial coinfection and death. Thus, health care providers should minimize hospitalization as well as following a continuous monitoring for bacterial coinfection among COVID-19 patients, to control the spread of infection and reducing the severity and mortality rate among COVID-19 patients.
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