47 research outputs found
Assessment of patientsâ knowledge of tuberculosis and its impact on self-management ability
Purpose: To assess the knowledge of patients of tuberculosis (TB) and its relationship with patientsâ self-management in Saudi Arabia.
Methods: The study is based a prospective cross-sectional design. It included a sample of 176 cases with an active or latent diagnosis of TB. A survey was conducted in some hospitals, including King Abdul-Aziz University from November 2016 to January 2017. The collected data were statistically analyzed.
Results: The survey showed that 70 % of the patients had inadequate information on TB and its treatment, while only 4 % showed awareness of the prevalence of TB. Moreover, a significant correlation was found between the educational level of patients and their knowledge of TB. Patientsâ educational level substantially contributed to their understanding of health education.
Conclusion: The findings suggest that active educational campaigns need to be initiated to enhance the patientsâ awareness and knowledge of TB
Investigating the Effects of Alternative Fuels with Different Aromatic Species on Compression Ignition Engine Emissions and Performance
Harmful emissions are the major challenge for combustion systems and continuously increasing with the use of fossil-based feedstock around the globe. Compression ignition engine (CI) is one of the main emitters of harmful pollutants. As compared to spark ignition (SI) engine, CI engine produces high particulate matter (PM) and nitrogen oxides (NOx) emissions. The need for the improvement of engine performance; fuel consumption and thermal efficiency is another challenge. Investigating the effect of fuel components is one of the approaches that can be used to reduce exhaust emissions and improve performance.
knowledge gaps need to be completed in how different aromatic species of the same type impact the engine performance and emissions. The contributions of the present study are in the detailed investigations reporting and analyzing the role of different alkylbenzenes and polycyclic aromatics in surrogate fuels on emissions and engine performance. This knowledge would help the future fuel industry to produce future fuels with appropriate alkylbenzenes and polycyclic aromatics for lower emissions and improved performance. In addition, the study provides more details about the influence of different aromatic concentrations in the fuel on emissions and performance.
To attain the aims of the current study, different alkylbenzenes and polycyclic aromatics were blended with surrogate fuel at three different contents. The blended fuels were tested experimentally using a direct injection (DI) CI engine at two different load conditions. Appropriate sampling line, particulate and gaseous species measurement instrumentation were integrated with the engine rig in order to take measurements accurately. Impact of different properties of aromatic species on PM, NOx UHCâs, CO and engine performance has also been investigated and forms a part of contribution to knowledge.
The overall results show that increasing aromatic content in fuel contributes to high levels of exhaust emissions and impacts engine performance. Comparison among alkylbenzenes surrogate blends presents that blends containing ethylbenzene produce low exhaust emissions and better performance because of its properties; high calorific value, cetane number, low density and hydrogen-to-carbon (H/C) ratio. While, indane surrogate blends have better results as compared to other polycyclic aromatics. Finally, optimum surrogate blend is formed with appropriate aromatics (ethylbenzene and indane). Operating the engine with optimum blend results in significant reduction of PM, smoke, unburned hydrocarbons (UHC) as compared to commercial diesel fuel. However, increase of brake thermal efficiency (BTE), reduction of NOx and brake specific fuel consumption (BSFC) are insignificant. NOx and PM correlations are developed as a function of significant impacted fuel properties. The prediction models developed are highly agreeing with experimental results. Overall, this work would provide basis for selection of aromatic species in future fuels, as not all aromatic species lead to higher PM, NOx or give the optimal engine performance
The reproductive potential of vitrifiedwarmed euploid embryos declines following repeated uterine transfers
Background Recurrent implantation failure (RIF) represents a vague clinical condition with an unclear diagnostic
challenge that lacks solid scientific underpinning. Although euploid embryos have demonstrated consistent
implantation capabilities across various age groups, a unanimous agreement regarding the advantages of
preimplantation genetic testing for aneuploidy (PGT-A) in managing RIF is absent. The ongoing discussion about
whether chromosomal aneuploidy in embryos significantly contributes to recurrent implantation failure remains
unsettled. Despite active discussions in recent times, a universally accepted characterization of recurrent implantation
failure remains elusive. We aimed in this study to measure the reproductive performance of vitrified-warmed euploid
embryos transferred to the uterus in successive cycles.
Methods This observational cohort study included women (n = 387) with an anatomically normal uterus who
underwent oocyte retrieval for PGT-A treatment with at least one biopsied blastocyst, between January 2017 and
December 2021 at a university-affiliated public fertility center. The procedures involved in this study included ICSI,
blastocyst culture, trophectoderm biopsy and comprehensive 24-chromosome analysis of preimplantation embryos
using Next Generation Sequencing (NGS). Women, who failed a vitrified-warmed euploid embryo transfer, had
successive blastocyst transfer cycles (FET) for a total of three using remaining cryopreserved euploid blastocysts from
the same oocyte retrieval cycle. The primary endpoints were sustained implantation rate (SIR) and live birth rate (LBR)
per vitrified-warmed single euploid embryo. The secondary endpoints were mean euploidy rate (m-ER) per cohort of
biopsied blastocysts from each patient, as well as pregnancy and miscarriage rates.
Results The mean age of the patient population was 33.4 years (95% CI 32.8â33.9). A total of 1,641 embryos derived
from the first oocyte retrieval cycle were biopsied and screened. We found no associations between the m-ER and
the number of previous failed IVF cycles among different ranges of maternal age at oocyte retrieval (P = 0.45). Pairwise
comparisons showed a significant decrease in the sustained implantation rate (44.7% vs. 30%; P = 0.01) and the
livebirth rate per single euploid blastocyst (37.1% vs. 25%; P = 0.02) between the 1st and 3rd FET. The cumulative SIR
and LBR after up to three successive single embryo transfers were 77.1% and 68.8%, respectively. We found that the live birth rate of the first vitrified-warmed euploid blastocyst transferred decreased significantly with the increasing
number of previously failed IVF attempts by categories (45.3% vs. 35.8% vs. 27.6%; P = 0.04). A comparable decrease in
sustained implantation rate was also observed but did not reach statistical significance (50% vs. 44.2 vs. 37.9%; P = NS).
Using a logistic regression model, we confirmed the presence of a negative association between the number of
previous IVF failed attempts and the live birth rate per embryo transfer cycle (OR = 0.76; 95% CI 0.62â0.94; P = 0.01).
Conclusions These findings are vital for enhancing patient counseling and refining management strategies
for individuals facing recurrent implantation failure. By tailoring interventions based on age and ovarian reserve,
healthcare professionals can offer more personalized guidance, potentially improving the overall success rates and
patient experiences in fertility treatments
Optimization of Cobalt Nanoparticles for Biogas Enhancement from Green Algae Using Response Surface Methodology
Organic matter may be converted to energy through various methods, but the most preferable one is the Anaerobic Digestion (AD), specifically for biogas production. In sustainable bioenergy production, it can undoubtedly be called one of the most widely used methods from the various feedstock. Over the past years, algae waste has become an increasingly acute environmental problem but luckily it can be used as feedstock to produce bioenergy. In order to improve the energy productivity of green algae, this study is focused on the introduction of cobalt (Co) nanoparticles (NPs) in the AD process. The concentration of Co NPs was optimized using response surface methodology (RSM). Mesophilic temperature range (25â45 °C), initial pH (5â9) and Co NPs dosage (0.5â2 mg/L) were selected as the independent variables for RSM. The results indicated that at optimized values (Co NPs concentration = 1 mg/L, initial pH = 7, and digestion temperature = 35 °C) produced the highest biogas yield of 298 ml. An experiment was carried out at optimized conditions to explore the effect on biogas production. The results showed that Co NPs had a positive influence on biogas yield. The low concentrations achieved higher biogas production as compared to higher ones. A maximum biogas yield of 678 mL is achieved by Co NPs (1 mg/L). AD performance was further evaluated by the modified Gompertz model. Different kinetic parameters were calculated. The values of the performance indicators confirmed that the mathematical model fitted well with experimental data
The design and implementation of an Arabic pronunciation application for early childhood
Learning is not limited to a certain age group or a formal study environment. However, the first eight years, and particularly the first three years, are most important, as the effects of the care and attention provided to the child during this period will continue throughout his or her life. A childâs early learning processes develop their educational abilities and skills, and fosters their academic achievements.
Preschool can be very benefit to development and learning for children, but there are differences between countries in this area. It can reduce the repetition in the classroom and can raise achievement scores for students through the preschool programs of high quality (Jacobson and Linda 2008). There are many applications in the Middle East that teach kids, but there is didn't link between the vowels of the Arabic alphabet characters and verbally voice for each character and training to select correct format of Arabic alphabet like (fatha, dama and kasra).
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This study aims to develop an educational application for children from the ages of 3 to 5 to help them improve their skills and abilities. The application will also prepare them for school by teaching them the Arabic letters, pronunciation and the short vowels (fatha, dama and kasra). The application also aims to help children communicate and interact more effectively with their external environment by employing several theories about learning skills, such as Piagetâs Theory of Cognitive Development, Edger Daleâs Cone of Learning and Bloom's Taxonomy of Cognitive Goals. The application will focus on the first three levels of Bloom's Taxonomy Pyramid which are âRememberâ, âUnderstandâ and âApplyâ. Furthermore, the application will be designed to aid children with their Arabic pronunciation, and aural and oral skills, and train and educate them in preparation for attending school. The expected result is that it will be considerably better than educational books for childrenâs education. Combining education and play in e-learning applications is an important way to attract children
An implementation of an aeroacoustic prediction model for broadband noise from a vertical axis wind turbine using a CFD informed methodology
This paper presents an enhanced method for predicting aerodynamically generated broadband noise produced by a Vertical Axis Wind Turbine (VAWT). The method improves on existing work for VAWT noise prediction and incorporates recently developed airfoil noise prediction models. Inflow-turbulence and airfoil self-noise mechanisms are both considered. Airfoil noise predictions are dependent on aerodynamic input data and time dependent Computational Fluid Dynamics (CFD) calculations are carried out to solve for the aerodynamic solution. Analytical ow methods are also benchmarked against the CFD informed noise prediction results to quantify errors in the former approach. Comparisons to experimental noise measurements for an existing turbine are encouraging. A parameter study is performed and shows the sensitivity of overall noise levels to changes in inflow velocity and inflow turbulence. Noise sources are characterised and the location and mechanism of the primary sources is determined, inflow-turbulence noise is seen to be the dominant source. The use of CFD calculations is seen to improve the accuracy of noise predictions when compared to the analytic ow solution as well as showing that, for inflow-turbulence noise sources, blade generated turbulence dominates the atmospheric inflow turbulence
COVID-19 first lockdown as a window into language acquisition: Associations between caregiver-child activities and vocabulary gains
The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in childrenâs learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and childrenâs language development. The vocabularies of 1742 children aged8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries(from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their childâs development or vocabulary development benefited from intense caregiver-child interaction during lockdown
COVID-19 first lockdown as a window into language acquisition : associations between caregiver-child activities and vocabulary gains
The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in childrenâs learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and childrenâs language development. The vocabularies of 1742 children aged8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries(from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their childâs development or vocabulary development benefited from intense caregiver-child interaction during lockdown
COVID-19 first lockdown as a window into language acquisition: Associations between caregiver-child activities and vocabulary gains
The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in childrenâs learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and childrenâs language development. The vocabularies of 1742 children aged 8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries (from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their childâs development or vocabulary development benefited from intense caregiver-child interaction during lockdown