319 research outputs found
Applications of Soft Sets in -Algebras
In 1999, Molodtsov introduced the concept of soft set theory as a general mathematical tool for dealing with uncertainty and vagueness. In this paper, we apply the concept of soft sets to K-algebras and investigate some properties of Abelian soft K-algebras. We also introduce the concept of soft intersection K-algebras and investigate some of their properties
A Novel Fluoride Containing Bioactive Glass Paste is Capable of Re-Mineralizing Early Caries Lesions
e Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah, Under grant No. (D-046-165-1438
Effect of Dietary Simulating Solvents on the CAD-CAM Provisional Restorative Materials’ Microhardness and Color Stability Properties: An in vitro Study
Haidar Alalawi,1 Sarah Al-Qanas,2 Sarah Al-Ghamdi,2 Raghad Al-Fuhaid,2 Soban Khan,3 Maram A AlGhamdi,1 Khalid S Almulhim,4 Faisal E Aljofi,5 Zahid A Khan,1 Yousif A Al-Dulaijan1 1Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 2College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 3Department of Dental Education, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 4Department of Restorative Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 5Department of Preventive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi ArabiaCorrespondence: Yousif A Al-Dulaijan, Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia, Tel +966 13 333 1462, Email [email protected]: This in vitro study investigated the effects of dietary solvents on the microhardness and color stability of CAD/CAM provisional restorations compared to conventional materials.Methods: Disc-shaped specimens (n=200) were fabricated from self-cured acrylic resin, two 3D-printing resins (FormLabs, NextDent), and a milled material (TelioCAD). Randomization assigned specimens (n=10/group) to immersion solutions: artificial saliva, citric acid, heptane, coffee, and tea. Microhardness and color stability were evaluated. One-way and three-way ANOVA with Tukey’s post hoc test analyzed the data.Results: Dietary solvents significantly reduced the surface microhardness of all tested materials (p< 0.05). Unpolished surfaces exhibited greater color changes compared to polished ones (p< 0.05) across all materials. Coffee and tea induced the most substantial reductions in hardness and the most significant color alterations (p< 0.05), whereas saliva and citric acid had minimal effects.Conclusion: Milled provisional restorations exhibited superior hardness and color stability. Dietary solvents significantly affected material properties over time, highlighting the importance of material selection for clinical applications.Keywords: 3D-printed, color stability, food, microhardness, milled, self-cure resi
A systematic review and meta-analysis of heart rate variability in COPD
Background: Chronic obstructive pulmonary disease (COPD) is associated with disruption in autonomic nervous control of the heart rhythm. We present here quantitative evidence of the reduction in HRV measures as well as the challenges to clinical application of HRV in COPD clinics. Method: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we search in June 2022 Medline and Embase databases for studies reporting HRV in COPD patients using relevant medical subject headings (MeSH) terms. The quality of included studies was assessed using the modified version of the Newcastle–Ottawa Scale (NOS). Descriptive data were extracted, while standardized mean difference was computed for changes in HRV due to COPD. Leave-one-out sensitivity test was performed to assess exaggerated effect size and funnel plots to assess publication bias. Results: The databases search yielded 512 studies, of which we included 27 that met the inclusion criteria. The majority of the studies (73%) had a low risk of bias and included a total of 839 COPD patients. Although there were high between-studies heterogeneity, HRV time and frequency domains were significantly reduced in COPD patients compared with controls. Sensitivity test showed no exaggerated effect sizes and the funnel plot showed general low publication bias. Conclusion: COPD is associated with autonomic nervous dysfunction as measured by HRV. Both sympathetic and parasympathetic cardiac modulation were decreased, but there is still a predominance of sympathetic activity. There is high variability in the HRV measurement methodology, which affects clinical applicability
Bleu Arabia: Palaeolithic and underwater survey in SW Saudi Arabia and the role of coasts in Pleistocene dispersals
The role of coastal regions and coastlines in the dispersal of human populations from Africa and across the globe has been highlighted by the recent polarisation between coastal and interior models. The debate has been clouded by the use of the single term ‘coastal dispersal’ to embrace what is in fact a wide spectrum of possibilities, ranging from seafaring populations who spend most of their time at sea living off marine resources, to land-based populations in coastal regions with little or no reliance on marine foods. An additional complicating factor is the fact of Pleistocene and early Holocene sea-level change, which exposed an extensive coastal region that is now submerged, and may have afforded very different conditions from the modern coastal environment. We examine these factors in the Arabian context and use the term ‘Blue’ to draw attention to the fertile coastal rim of the Arabian Peninsula, and to the now submerged offshore landscape, which is especially extensive in some regions. We further emphasise that the attractions of the coastal rim are a product of two quite different factors, ecological diversity and abundant water on land, which have created persistently ‘Green’ conditions throughout the vagaries of Pleistocene climate change in some coastal regions, especially along parts of the western Arabian escarpment, and potentially productive marine environments around its coastline, which include some of the most fertile in the world. We examine the interplay of these factors in the Southwest region of Saudi Arabia and the southern Red Sea, and summarise some of the results of recent DISPERSE field investigations, including survey for Palaeolithic sites on the mainland, and underwater survey of the continental shelf in the vicinity of the Farasan Islands. We conclude that coastlines are neither uniformly attractive nor uniformly marginal to human dispersal, that they offer diverse opportunities that were spatially and temporally variable at scales from the local to the continental, and that investigating Blue Arabia in relation to its episodically Green interior is a key factor in the fuller understanding of long-term human population dynamics within Arabia and their global implications
Evaluating The Application Of Infection Control Standards In Health Facilities In Mecca
The study aims to determine the seriousness or continuity of applying infection control standards in health facilities, and the extent of the importance of applying them to workers in health facilities even after health centers have obtained the accreditation certificate for quality standards in health facilities (CBAHI) for more than 6 years. The questionnaire was distributed electronically via social media, in order to prevent crowding and avoid the spread of the Coronavirus-19. 700 questionnaires were distributed to employees who work in health facilities, and only 680 questionnaires were answered
Evaluation of a task-based community oriented teaching model in family medicine for undergraduate medical students in Iraq
BACKGROUND: The inclusion of family medicine in medical school curricula is essential for producing competent general practitioners. The aim of this study is to evaluate a task-based, community oriented teaching model of family medicine for undergraduate students in Iraqi medical schools. METHODS: An innovative training model in family medicine was developed based upon tasks regularly performed by family physicians providing health care services at the Primary Health Care Centre (PHCC) in Mosul, Iraq. Participants were medical students enrolled in their final clinical year. Students were assigned to one of two groups. The implementation group (28 students) was exposed to the experimental model and the control group (56 students) received the standard teaching curriculum. The study took place at the Mosul College of Medicine and at the Al-Hadba PHCC in Mosul, Iraq, during the academic year 1999–2000. Pre- and post-exposure evaluations comparing the intervention group with the control group were conducted using a variety of assessment tools. RESULTS: The primary endpoints were improvement in knowledge of family medicine and development of essential performance skills. Results showed that the implementation group experienced a significant increase in knowledge and performance skills after exposure to the model and in comparison with the control group. Assessment of the model by participating students revealed a high degree of satisfaction with the planning, organization, and implementation of the intervention activities. Students also highly rated the relevancy of the intervention for future work. CONCLUSION: A model on PHCC training in family medicine is essential for all Iraqi medical schools. The model is to be implemented by various relevant departments until Departments of Family medicine are established
The correlation between endometrial thickness and outcome of in vitro fertilization and embryo transfer (IVF-ET) outcome
<p>Abstract</p> <p>Background</p> <p>To evaluate the relationship between endometrial thickness on day of human chorionic gonadotrophin administration (hCG) and pregnancy outcome in a large number of consecutive in vitro fertilization and embryo transfer (IVF-ET) cycles.</p> <p>Methods</p> <p>A retrospective cohort study including all patients who had IVF-ET from January 2003–December 2005 conducted at a tertiary center.</p> <p>Results</p> <p>A total of 2464 cycles were analysed. Pregnancy rate (PR) was 35.8%. PR increased linearly (r = 0.864) from 29.4% among patients with a lining of less than or equal to 6 mm, to 44.4% among patients with a lining of greater than or equal to 17 mm. ROC showed that endometrial thickness is not a good predictor of PR, so a definite cut-off value could not be established (AUC = 0.55).</p> <p>Conclusion</p> <p>There is a positive linear relationship between the endometrial thickness measured on the day of hCG injection and PR, and is independent of other variables. Hence aiming for a thicker endometrium should be considered.</p
A review of patients who suddenly deteriorate in the presence of paramedics
<p>Abstract</p> <p>Background</p> <p>The report of the Ministerial Review of Trauma and Emergency Services in Victoria, Australia, recommended that paramedics be permitted to divert to the closest hospital in incidences of life threatening situations prior to and during transport. An audit of patients that suddenly deteriorated in paramedic care was recommended by the Ministerial Review. The objective of the study was to identify the number and outcome of patients who suddenly deteriorated in the presence of paramedics.</p> <p>Methods</p> <p>A retrospective cohort study of trauma patients who suddenly deteriorated in the presence of paramedics during 2002. As there was no standard definition, sudden deterioration was defined using a predetermined set of physiological criteria. Patient care record data of patients who suddenly deteriorated were compared with the State Trauma Registry to determine those who sustained hospital defined major trauma. Patient care records where hospital bypass was undertaken were identified and analysed. Ethics committee approval was obtained.</p> <p>Results</p> <p>There were 2,893 patients that suddenly deteriorated according to predefined criteria. 2,687 (5.1% of the total trauma patients for 2002) were suitable for further analysis. The majority of patients had a sudden decrease in BP (n = 2,463) with 4.3% having hospital defined major trauma. For patients with a sudden decrease in conscious state or a total GCS score of less than 13 (n = 77), 37.7% had hospital defined major trauma; and a sudden increase/decrease in pulse rate and sudden decrease in BP (n = 65), 26.2% had hospital defined major trauma. Only 28 documented incidents of hospital bypass were identified.</p> <p>Conclusion</p> <p>This study suggests that the incidents of patients suddenly deteriorating in the presence of paramedics are low and the incidence of hospital bypass is not well documented.</p
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