140 research outputs found

    Hermite collocation method for solving Hammerstein integral equations

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    In this paper, we are presenting Hermite collocation method to solve numer- ically the Fredholm-Volterra-Hammerstein integral equations. We have clearly presented a theory to …nd ordinary derivatives. This method is based on replace- ment of the unknown function by truncated series of well known Hermite expan-sion of functions. The proposed method converts the equation to matrix equation which corresponding to system of algebraic equations with Hermite coe¢ cients. Thus, by solving the matrix equation, Hermite coe¢ cients are obtained. Some numerical examples are included to demonstrate the validity and applicability of the proposed technique

    Inventory Analysis Using the ABC-Ved Matrix - Applied Research in Al-Zawraa State Company

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    Purpose: The aim of this study is to examine or analyze the inventory by integrating the analyzes of ABC and VED and take advantage of their advantages together by forming an ABC-VED matrix to classify the inventory according to the cost criteria and the functional importance of the inventory items.   Theoretical framework: The ABC-VED matrix consists of ABC analysis, VED analysis, and then the ABC-VED matrix.   Design / Methodology / Approach: The researcher relied on the case study approach in this research, due to the multiplicity of features and benefits of this approach by using more than one research method at the same time to obtain the maximum benefit related to the case under study, In addition to the fact that this approach helps in a comprehensive and in-depth analysis of the researched problem by obtaining a large amount of information for all events related to the researched case, Where the researcher seeks through this research to analyze the inventory according to the ABC-VED matrix to classify the inventory into three categories according to the criteria of cost and the functional importance of the inventory.   Finding: The results show that the use of the ABC-VED matrix helped Al-Zawra State Company to control, organize and manage its inventory of raw materials and spare parts in more efficient ways, by classifying it into three categories according to the criteria of cost and critical importance, by focusing on the first category and giving it great attention and care because of its high cost, and its great importance.   Research, practical & social implications: The study is expected to help control inventory because of its classification into three categories according to the criteria of cost and the functional importance of raw materials and spare parts for the company in the field of research or other companies wishing to control their inventory.   Originality / Value: The value of the study focuses on the analysis of inventory in Al-Zawraa State Company, and this research responds to addressing the problems of inventory in the company in the field of research by classifying it into three master categories for the purpose of controlling and managing it better

    A simulation model of infant-incubator-feedback system with humidification and temperature control

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    A comprehensive simulation model for the infant-incubator-feedback system was developed in a Matlab/Simulink® environment to investigate all heat exchange relationships, variables and factors that have an influence on the overall thermo-neutrality of the environment. The model was also used to determine the benefits and limitations of using a convectively heated single-walled incubator in nursing preterm infants with very low birth weight < 1000 grams and low gestational age 28 weeks. The infant was modelled as one-lump with two layers; core and skin. The infant shape was approximated to a cylinder. The model incorporated all compartments of the infant-incubator system including core, skin, incubator air space, mattress, incubator walls, air-circulating fan, heating element, added oxygen (for resuscitation purposes), and humidification chamber, which has not previously been considered. The results of the simulation were in terms of the temperature variation over time, of the following parts of the system: core and skin temperatures and incubator air space temperature. Results of the simulation with added humidity showed that the body temperature of a 900 gram infant, with an initial body temperature of 35.5 ºC, did not reach the thermo-neutral range between 36.5-37.5 ºC in two hours, on air mode. Whereas, on skin mode, both core and skin temperature reached to 36.87 ºC and 36.5 ºC in two hours, and thus a thermo-neutral environment was achieved. These outcomes are consistent with clinical empirical reports. The simulation model is a closed-loop system with a PID controller for each mode; air servo controlled and skin servo controlled. The controller parameters were virtually estimated by the Zeigler-Nichols Method as real values were not available. Nevertheless, the overall stability of the whole system has been achieved by applying a step input which was verified by the Root Locus Method

    The Role of Streptococcus mutans and Pathogenesis in the Oral cavity

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    &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;The oral cavity is a complex environment system where certain bacteria coexist with human chemical compounds. However, changes in the natural structure of the bacteria may lead to the onset of oral disease, such as periodontitis and tooth decay. A number of different environments exist in the human oral cavity, colonized by more than 600 types of aerobic and anaerobic bacteria, including the teeth, gingival sulcus, hard and soft palates, and tonsils, but only a limited number of these types can cause tooth infection . &nbsp;&nbsp; The purpose from this study&nbsp; is an attempt to establish which characteristics associated with biofilm formation—virulence determinants of S. mutans—are responsible for the development of dental caries &nbsp;&nbsp; The review concluded the bacterial components that contribute to each of the major virulence properties and these are work together in the development of dental caries

    Medical doctors\u27 offline computer-assisted digital education: Systematic review by the digital health education collaboration

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    Background: The widening gap between innovations in the medical field and the dissemination of such information to doctors may affect the quality of care. Offline computer-based digital education (OCDE) may be a potential solution to overcoming the geographical, financial, and temporal obstacles faced by doctors.Objective: The objectives of this systematic review were to evaluate the effectiveness of OCDE compared with face-to-face learning, no intervention, or other types of digital learning for improving medical doctors\u27 knowledge, cognitive skills, and patient-related outcomes. Secondary objectives were to assess the cost-effectiveness (CE) of OCDE and any adverse effects.Methods: We searched major bibliographic databases from 1990 to August 2017 to identify relevant articles and followed the Cochrane methodology for systematic reviews of intervention.Results: Overall, 27 randomized controlled trials (RCTs), 1 cluster RCT (cRCT), and 1 quasi-RCT were included in this review. The total number of participants was 1690 in addition to the cRCT, which included 24 practices. Due to the heterogeneity of the participants, interventions, and outcomes, meta-analysis was not feasible, and the results were presented as narrative summary. Compared with face-to-face learning, the effect of OCDE on knowledge gain is uncertain (ratio of the means [RM] range 0.95-1.17; 8 studies, 495 participants; very low grade of evidence). From the same comparison, the effect of OCDE on cognitive skill gain is uncertain (RM range 0.1-0.9; 8 studies, 375 participants; very low grade of evidence). OCDE may have little or no effect on patients\u27 outcome compared with face-to-face education (2 studies, 62 participants; low grade of evidence). Compared with no intervention, OCDE may improve knowledge gain (RM range 1.36-0.98; 4 studies, 401 participants; low grade of evidence). From the same comparison, the effect of OCDE on cognitive skill gain is uncertain (RM range 1.1-1.15; 4 trials, 495 participants; very low grade of evidence). One cRCT, involving 24 practices, investigated patients\u27 outcome in this comparison and showed no difference between the 2 groups with low-grade evidence. Compared with text-based learning, the effect of OCDE on cognitive skills gain is uncertain (RM range 0.91-1.46; 3 trials with 4 interventions; 68 participants; very low-grade evidence). No study in this comparison investigated knowledge gain or patients\u27 outcomes. One study assessed the CE and showed that OCDE was cost-effective when compared with face-to-face learning if the cost is less than or equal to Can $200. No trial evaluated the adverse effect of OCDE.Conclusions: The effect of OCDE compared with other methods of education on medical doctors\u27 knowledge and cognitive skill gain is uncertain. OCDE may improve doctors\u27 knowledge compared with no intervention but its effect on doctors\u27 cognitive skills is uncertain. OCDE may have little or no effect in improving patients\u27 outcome

    Conversion of Uric Acid into Ammonium in Oil-Degrading Marine Microbial Communities: a Possible Role of Halomonads

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    Uric acid is a promising hydrophobic nitrogen source for biostimulation of microbial activities in oil-impacted marine environments. This study investigated metabolic processes and microbial community changes in a series of microcosms using sediment from the Mediterranean and the Red Sea amended with ammonium and uric acid. Respiration, emulsification, ammonium and protein concentration measurements suggested a rapid production of ammonium from uric acid accompanied by the development of microbial communities containing hydrocarbonoclastic bacteria after 3 weeks of incubation. About 80 % of uric acid was converted to ammonium within the first few days of the experiment. Microbial population dynamics were investigated by Ribosomal Intergenic Spacer Analysis and Illumina sequencing as well as by culture-based techniques. Resulting data indicated that strains related to Halomonas spp. converted uric acid into ammonium, which stimulated growth of microbial consortia dominated by Alcanivorax spp. and Pseudomonas spp. Several strains of Halomonas spp. were isolated on uric acid as the sole carbon source showed location specificity. These results point towards a possible role of halomonads in the conversion of uric acid to ammonium utilized by hydrocarbonoclastic bacteria.With exception of XH and JC, all authors were supported by the FP7 Project ULIXES (FP7-KBBE-2010-266473). This work was further funded by grant BIO2011-25012 from the Spanish Ministry of the Economy and Competitiveness. FM was supported by Università degli Studi di Milano, European Social Fund (FSE) and Regione Lombardia (contract BDote Ricerca^). DD acknowledges support of KAUST, King Abdullah University of Science and Technology. PG acknowledges the support of the European Commission through the project Kill-Spill (FP7, Contract Nr 312139).Peer Reviewe

    The Impact of Age, Gender, Temporality, and Geographical Region on the Prevalence of Obesity and Overweight in Saudi Arabia: Scope of Evidence

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    OBJECTIVES: The objectives of this scoping review are to estimate the prevalence of obesity and overweight in the Saudi community and in different age groups, genders, and geographical location, in addition to the change in prevalence over time. METHODS: This scoping review of evidence was conducted in accordance with the Joanna Briggs Institute methodology for scoping reviews and was reported following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The population of this review was categorized into four age groups: young adults (18-25 years), adults (26-45), (mid-life adults) (46-60) and old people (60+). Each group was then categorized by gender into males and females. We included studies of adults aged 18 years and above. The pooled prevalence of obesity and overweight of the population, based on BMI, was estimated after stratification based on the age, gender, and geographical area. In addition, the change in the prevalence of obesity/overweight over time from 2011 to 2021 was investigated from the pooled data. The Metaprop program in Stata was used for statistical analysis. RESULTS: A total of 39 studies with 640,952 participants were included in this review. The pooled prevalence of obesity and overweight in the age group of ≤25 years old, including both genders, was 30%. However, it was higher in young males (40%) compared to young females (25%). The prevalence of obesity and overweight among young adults has dropped by over 40% between 2012 and 2021. The overall pooled prevalence rate of obesity and overweight in the age groups >25 years old (adults, mid-life, and old people), including both genders, was 66%, with similar prevalence among males (68%) and females (71%). In addition, a similar prevalence was observed among both adult and old people (62% and 65%, respectively), but was higher in the mid-life group (76%). Furthermore, mid-life women had the highest prevalence among all groups (87%), compared to 77% among males in the same age group. The same difference in prevalence between the gender persisted in older females compared to older males (79% vs. 65%, respectively). There is a noticeable drop in the pooled prevalence of overweight and obesity among adults > 25 years old of over 28% between 2011 and 2021. There was no difference in the prevalence of obesity/overweight by geographical region. CONCLUSIONS: Despite the noticeable drop in the prevalence of obesity in the Saudi community, the prevalence of high BMI is high in Saudi Arabia irrespective of age, gender, or geographical location. Mid-life women have the highest prevalence of high BMI, which makes them the focus of a tailored strategy for intervention. Further research is needed to investigate which are the most effective interventions to address obesity in the country

    Systematic review and meta-analysis of the effectiveness of pre-pregnancy care for women with diabetes for improving maternal and perinatal outcomes.

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    BACKGROUND: Pre-gestational diabetes mellitus is associated with increased risk of maternal and perinatal adverse outcomes. This systematic review was conducted to evaluate the effectiveness and safety of pre-conception care (PCC) in improving maternal and perinatal outcomes. METHODS: Databases from MEDLINE, EMBASE, WEB OF SCIENCE, and Cochrane Library were searched, including the CENTRAL register of controlled trials, and CINHAL up until March 2019, without any language restrictions, for any pre-pregnancy care aiming at health promotion, glycemic control, and screening and treatment of diabetes complications in women with type I or type II pre-gestational diabetes. Trials and observational studies were included in the review. Newcastle-Ottawa scale and the Cochrane collaboration methodology for data synthesis and analysis were used, along with the GRADE tool to evaluate the body of evidence. RESULTS: The search identified 8500 potentially relevant citations of which 40 reports of 36 studies were included. The meta-analysis results show that PCC reduced congenital malformations risk by 71%, (Risk ratio (RR) 0.29; 95% CI: 0.21-0.40, 25 studies; 5903 women; high-certainty evidence). The results also show that PCC may lower HbA1c in the first trimester of pregnancy by an average of 1.27% (Mean difference (MD) 1.27; 95% CI: 1.33-1.22; 4927 women; 24 studies, moderate-certainty evidence). Furthermore, the results suggest that PCC may lead to a slight reduction in the risk of preterm delivery of 15%, (RR 0.85; 95% CI: 0.73-0.99; nine studies, 2414 women; moderate-certainty evidence). Moreover, PCC may result in risk reduction of perinatal mortality by 54%, (RR 0.46; 95% CI: 0.30-0.73; ten studies; 3071 women; moderate-certainty evidence). There is uncertainty about the effects of PCC on the early booking for antenatal care (MD 1.31; 95% CI: 1.40-1.23; five studies, 1081 women; very low-certainty evidence) and maternal hypoglycemia in the first trimester, (RR 1.38; 95% CI: 1.07-1.79; three studies; 686 women; very low- certainty evidence). In addition, results of the meta-analysis indicate that PCC may lead to 48% reduction in the risk of small for gestational age (SGA) (RR 0.52; 95% CI: 0.37-0.75; six studies, 2261 women; moderate-certainty evidence). PCC may reduce the risk of neonatal admission to intensive care unit (NICU) by 25% (RR 0.75; 95% CI: 0.67-0.84; four studies; 1322 women; moderate-certainty evidence). However, PCC may have little or no effect in reducing the cesarean section rate (RR 1.02; 95% CI: 0.96-1.07; 14 studies; 3641 women; low-certainty evidence); miscarriage rate (RR 0.86; 95% CI: 0.70-1.06; 11 studies; 2698 women; low-certainty evidence); macrosomia rate (RR 1.06; 95% CI: 0.97-1.15; nine studies; 2787 women, low-certainty evidence); neonatal hypoglycemia (RR 0.93; 95% CI: 0.74-1.18; five studies; 880 women; low-certainty evidence); respiratory distress syndrome (RR 0.78; 95% CI: 0.47-1.29; four studies; 466 women; very low-certainty evidence); or shoulder dystocia (RR 0.28; 95% CI: 0.07-1.12; 2 studies; 530 women; very low-certainty evidence). CONCLUSION: PCC for women with pre-gestational type 1 or type 2 diabetes mellitus is effective in improving rates of congenital malformations. In addition, it may improve the risk of preterm delivery and admission to NICU. PCC probably reduces maternal HbA1C in the first trimester of pregnancy, perinatal mortality and SGA. There is uncertainty regarding the effects of PCC on early booking for antenatal care or maternal hypoglycemia during the first trimester of pregnancy. PCC has little or no effect on other maternal and perinatal outcomes

    Bacterial Diversity and Bioremediation Potential of the Highly Contaminated Marine Sediments at El-Max District (Egypt, Mediterranean Sea)

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    Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt). Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters. Fifty strains were isolated on mineral media supplemented by 1% crude oil and identified as a diverse range of hydrocarbon-degrading bacteria involved in different successional stages of biodegradation. We screened the collection for biotechnological potential studying biosurfactant production, biofilm formation, and the capability to utilize different hydrocarbons. Some strains were able to grow on multiple hydrocarbons as unique carbon source and presented biosurfactant-like activities and/or capacity to form biofilm and owned genes involved in different detoxification/degradation processes. El-Max sediments represent a promising reservoir of novel bacterial strains adapted to high hydrocarbon contamination loads. The potential of the strains for exploitation for in situ intervention to combat pollution in coastal areas is discussed
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