University of Zawia
  • Az Zāwīyah, Zawia, Libya
Recent publications
Nitrogen-rich materials such as poultry litter (PL) contributes to substantial N and C loss in the form of ammonia (NH 3) and carbon dioxide (CO 2) during composting. Biochar can act as a sorbent of ammonia (NH 3) and CO 2 emission released during co-composting. Thus, co-composting poultry litter with rice husk biochar as a bulking agent is a good technique to mitigate NH 3 volatilization and CO 2 emission. A study was conducted to evaluate the effects of composting the mixtures of poultry litter with rice husk biochar at different ratios on NH 3 and CO 2 emissions. Four mixtures of poultry litter and rice husk biochar at different rate were composted at 0:1, 0.5:1, 1.3:1 and 2.3:1 ratio of rice husk biochar (RHB): poultry litter (PL) on a dry weight basis to achieve a suitable C/ N ratio of 15, 20, 25, and 30, respectively. The results show that composting poultry litter with rice husk biochar can accelerate the breakdown of organic matter, thereby shortening the thermophilic phase compared to com-posting using poultry litter alone. There was a significant reduction in the cumulative NH 3 emissions, which accounted for 78.38%, 94.60%, and 97.30%, for each C/N ratio of 20, 25, and 30. The total nitrogen (TN) retained relative was 75.96%, 85.61%, 90.24%, and 87.89% for each C/N ratio of 15, 20, 25, and 30 at the completion of composting. Total carbon dioxide lost was 5.64%, 6.62%, 8.91%, and 14.54%, for each C/N ratio of 15, 20, 21, and 30. In addition, the total carbon (TC) retained were 66.60%, 72.56%, 77.39%, and 85.29% for 15, 20, 25, and 30 C/N ratios and shows significant difference as compared with the initial reading of TC of the compost mixtures. In conclusion, mixing and composting rice husk biochar in poultry litter with C/N ratio of 25 helps in reducing the NH 3 volatilization and CO 2 emissions, while reducing the overall operational costs of waste disposal by shortening the composting time alongside nitrogen conservation and carbon sequestration. In formulating the compost mixture with rice husk biochar, the contribution of C and N from the biochar can be neglected in the determination of C/N ratio to predict the rate of mineralization in the compost because biochar has characteristic of being quite inert and recalcitrant in nature.
In this study, firstly, novel vitamin K3 analogs were synthesized by the reactions of vitamin K3 (2-methyl-1,4-naphthoquinone, also known as menadione) with some aromatic and heterocyclic ring substituted nucleophiles such as 2,4-dimethoxyaniline, 4-methoxyaniline, 4-benzylpiperidine and 1-(2-aminoethyl)piperazine in ethanol/Na2CO3, and 1-(diphenylmethyl)piperazine in chloroform/triethylamine (TEA) at room temperature. Their structures were elucidated by Fourier transform infrared spectroscopy (FT-IR), ¹H nuclear magnetic resonance (¹H NMR), attached proton test nuclear magnetic resonance (APT-NMR) and mass spectrometry (MS). Secondly, in vitro cytotoxic effects of vitamin K3 analogs were investigated by MTT assay against three cancer cell lines (HeLa, U87 MG, and MCF-7) to evaluate their anticancer activity and a human embryonic kidney cell line (HEK-293) to check their cancer cell selectivity. One of the compounds, namely 2-((2,4-dimethoxyphenyl)amino)-3-methylnaphthalene-1,4-dione(5), was found to inhibit the growth of HeLa cervical cancer cells selectively, even better than vitamin K3, at a non-toxic concentration for healthy cells. The selectivity index of this compound for HeLa cells was calculated approximately as “3”. Vitamin K3 was more effective against U87 MG and MCF-7 cells than its derivatives, moreover it was the only compound, which was significantly toxic to breast cancer cells, but its selectivity was poor. Furthermore, anticancer properties of piperazine derivatives of vitamin K3 were investigated by us for the first time in this study. Graphical abstract Novel vitamin K3 analogs containing 3-N-substituted aromatic and piperazine rings with selective in vitro anticancer activity against HeLa, U87 MG, and MCF-7 cells
Background. In recent years, complete denture construction has been revolutionized using computer-aided designing and computer-aided manufacturing (CAD-CAM) technology. This clinical study compared the retention and denture base adaptation of 3D-printed complete dentures fabricated using dimethacrylate-based resins with a photoinitiator versus conventional complete dentures. Methods. Ten completely edentulous patients were nominated for this study. Each patient received two complete dentures. One complete denture was conventionally fabricated, while the other was digitally fabricated through 3D printing of dimethacrylate-based resins with a photoinitiator. Denture base adaptation for both dentures was evaluated using surface matching software. Denture retention was also evaluated using a digital force meter at the time of complete denture insertion (T 0), after three months (T 3) and six months (T 6) of denture use. Results. Regarding adaptation (mean misfit values), a statistically insignificant difference was detected between the two differently fabricated complete dentures. In addition, comparable satisfactory retention values were observed for both conventionally fabricated and 3D-printed dentures; however, there was an insignificant increase in retention over time. Conclusion. 3D-printed complete dentures fabricated using dimethacrylate-based resins could be a promising alternative to conventionally fabricated complete dentures with satisfactory denture base adaptation and retention.
The aim of this work was to establish a temperature of finish rolling stage of Nb/Ti microalloyed steel containing 0.06 wt.% C, 0.77 wt.% Mn, 0.039 wt.% Nb and 0.015 wt.% Ti, using physical simulation. Samples were subjected to laboratory simulation at a twist plastometer at high temperatures, i.e. between 825 and 950 °C. Five pass deformation and interpass times were selected in accordance with a processing parameters at five stand finishing hot strip mill. Restoration (recovery and/or recrystallization) behavior was evaluated by calculation of Fraction Softening (FS) and Area Softening Parameter (ASP) values. At 950 °C all individual pass stress-strain curves, FS and ASP show full recrystallization in all interpass intervals. On the other hand, with a decrease in temperature to the interval of 875-825 °C, the extent of restoration is decreasing, leading to recovery as a sole softening mechanism at 825 °C, which was confirmed by the stress-strain curve shape, and values of FS and ASP. It is assumed that, due to high supersaturation, strain-induced precipitation promoted pinning of grain and subgrain boundaries and suppressed recrystallization. Therefore, the critical temperature for finish rolling was estimated to be 825 °C.
COVID-19 has affected all aspects of human life so far. From the outset of the pandemic, preventing the spread of COVID-19 through the observance of health protocols, especially the use of sanitizers and disinfectants was given more attention. Despite the effectiveness of disinfection chemicals in controlling and preventing COVID-19, there are critical concerns about their adverse effects on human health. This study aims to assess the health effects of sanitizers and disinfectants on a global scale. A total of 91056 participants from 154 countries participated in this cross-sectional study through an electronic questionnaire. Results implied that detergents (67%), alcohol-based materials (56%), and chlorinated compounds (32%) were the most commonly used types of sanitizers and disinfectants. Most frequently reported health issues include skin complications 48.8% and respiratory complications 29.8%. The Chi-square test showed a significant association between chlorinated compounds with all possible health complications under investigation (p-value < 0.001). Examination of risk factors based on multivariate regression analysis showed that alcohols-based materials were associated with skin complications (OR, 1.98; 95%CI, 1.87–2.09), per-chlorine was associated with eye complications (OR, 1.83; 95%CI, 1.74–1.93), and highly likely with itching and throat irritation (OR, 2.00; 95%CI, 1.90–2.11). Furthermore, formaldehyde was associated with a higher prevalence of neurological complications (OR, 2.17; 95%CI, 1.92–2.44). The findings of the current study suggest that health authorities need to implement more awareness programs about the side effects of using sanitizers and disinfectants during viral epidemics.
ABSTRACT Traffic collision on the highway has become a serious issue because they delay the sustainable development of society. Highway accidents on I-69 have one of the highest crash rates in the U.S. in Michigan and a higher fatality rate than average. This study aimed to identify the factors contributing to highway user crashes on I-69 in Flint, Michigan. This study also aims to find the relationship between the change in the speed limit in certain weather conditions and the number of crashes that are likely to occur as a sequence of this change. A multi-user driving simulator is applied in this study with ten driving simulator scenarios. The multinomial logistic regression (MNL) model has been investigated in this study to identify statistically significant factors that contribute to crashes. The analyses indicated that speeding and speed limits during inclement road/weather conditions significantly affected crashes. Most frequent crashes occur during snowy and icy weather conditions and by changing the speed limit during these weather conditions. Therefore, driver speed is suspected to be the most factor that caused the Vehicle crash on I-69. The method of developing Crash modification factors (CMFs) used in this study will help to reduce crashes and improve traffic system safety performance on highways in Michigan.
This work introduces an experimental study to evaluate the effect of elevated temperatures on the mechanical properties of high-performance concrete (HPC) mix with changes in Water-Cementitious ratios, W/(C+SF), Silica Fume percent, SF, and Polypropylene, PP, fiber contents. This mix was typically designed to satisfy the requirements of tunnel concrete. The compressive and indirect tensile strengths were measured at room temperature, RT, and after exposure to 400°C and 800°C. Moreover, SEM micrograph and EDS spot analysis tests were done to evaluate the effect of elevated temperatures. Fifteen mixes of HPC with different ratios of W/(C+SF), SF, and PP fiber were tested. According to the test results, the compressive strength values of design mixes increased significantly after exposure to 400°C. Moreover, using SF = 10%, the results indicated remarkable improvements in the compressive strength at 400°C and 800°C, in the case of the W/(C+SF) ratio of 0.31. On the other hand, the highest effect of the presence of PP fibers was 0.211, depending on variable ratios of the W/(C+SF) ratio and the SF content. In the case of PP=0.106 and SF=10%, the mass loss was higher at exposure to temperatures of 800°C.
Mobile applications have become widespread in many aspects of our daily lives. Many people do most of their work via their phones, such as online banking, shopping, etc. Due to many individuals being unaware of their salary details, this paper presents a design and implementation of a Libyan salary application” الراتب” using Flutter (cross-platform). The application allows users to know details of their salaries, including bonuses and deductions according to the salary schedule of each ministry or sector. The application currently contains salary schedules for ten ministries. The implementation consists of the following four steps: data collection of laws and payroll tables for each ministry to use as a local database for the salary application, design of friendly-use application screens using Flutter, integration of the mobile application with Firebase) backend platform by Google), and finally, preparing and deploying an Android and web version of the salary application. The results that were obtained from reviewers in the Google Play Store were satisfactory. There is an increasing local demand to add other ministries to the application. The citizens of the local community encourage providing such a service, which is considered the first of its kind. The application reached more than 100k downloads in less than a year, and the average rating is 4.5 out of 5 in the Google Play Store at the time of writing this paper.
Objectives: A possible association between blood group systems (ABO and Rh) and coronavirus disease 2019 (COVID-19) severity has recently been investigated by various studies with conflicting results. However, due to variations in the prevalence of the ABO and Rh blood groups in different populations, their association with COVID-19 might be varied as well. Therefore, we conducted this study on Libyan participants to further investigate this association and make population-based data available to the worldwide scientific community. Methods: In this case-control study, ABO and Rh blood groups in 419 confirmed COVID-19 cases in Zawia, Libya, and 271 healthy controls were compared using descriptive statistics and χ 2 tests. Results: Blood group A was significantly more prevalent in patients with severe COVID-19 (64/125; 51.2%) than in patients with nonsevere COVID-19 (108/294, 36.7%) (P < .034), whereas the O blood group prevalence was higher in nonsevere COVID-19 cases (131/294, 44.5%) compared with severe cases (43/125, 34.4%) (P < .001). Conclusions: The results showed a significant association between blood group A and the severity of COVID-19, whereas patients with blood group O showed a low risk of developing severe COVID-19 infection. No significant association was found between Rh and susceptibility/severity of the disease.
In digital image analysis and processing field of study, noise reduction and suppression have been stated as a common query. However, it is mostly essential issue to demesne the fine edges and ridges and tiny texture while suppressing the noise in processing of the digital images. In order to avoid causing “Over-strangling” phenomenon, semi-soft thresholding model is exploited to classify the sharp edges of the contaminated images. In this study, a self-adjusting generative adversarial network GAN is utilized. This procedure is used to extract the fine edge of the noised digital images in order to improve the actual signal in the high frequency components where the main parts of the clean pixels may consider as noise pixels, and as a result delete the unwanted noise from the tested image that might cause over smoothing to the resulted images. In order to further denoise the contaminated digital image, adaptive learning GAN model throughout scoring machine is exploited. Therefore, it preserves the information of input image and feature maps, learns the correlation between global and local features, improves image restoration performance, and suppresses phenomena such as over-smoothing that tend to occur in wavelets-based denoising. The proposed method is an end-to-end network structure with CNN-based preprocessing methods. Experimental results demonstrate that, in comparison with state-of-the-art noise removal techniques, the proposed method has better visual quality, and the proposed method improves PSNR by 2.27 dB and 0.85 dB on average compared with state-of-the-art- denoising methods. In addition, the proposed method could shorten the processing time noticeably.
Dengue is classified as an endemic infectious disease, which is transmitted by Aedes mosquitos. Kinetic studies, which monitor the viral load of the disease, have been the mainstay for several decades in humanity's quest to control this disease. Our study aims to systematically evaluate the usage of different timing systems in dengue kinetic studies. A search in nine electronic databases and manual search of reference and citation lists were conducted to find relevant studies. A quality assessment using the National Institute of Health tools for observational cohort and cross-sectional studies was performed. The protocol was registered in PROSPERO with number CRD42018086435. As results, among included 87 studies, 71 studies (81.6%) use a timing system which is based on the day of illness onset, of which, 11 studies designate the day of illness onset as "day 0" (type 1A) while 60 studies designate it as "day 1" (type 1B). Only ten articles (11.5%) designate the day of defervescence as "day 0", the day before and after defervescence as "day -1" and "day +1", respectively. Four articles (4.6%) use a timing system based on the day of hospital admission. Lastly, two studies (2.3%) designate the day of hemorrhagic manifestation as "day 0" and two studies (2.3%) designate the day of pharmacological treatment as "day 1". Therefore, the timing system which designates the day of illness onset as "day 1" (type 1B) was most commonly used. Inconsistent definitions of "day 0" and "day 1" may lead to disparities in results across the studies and may have a negative impact on treatment guidelines implementation.
Breast plasmacytoma is relatively uncommon in which most of the recorded cases were related to disseminated multiple myeloma. However, many of these cases tend to be misdiagnosed with other breast lesions such as breast carcinoma. This article presents a case study on a Libyan female patient around the age of 55 who has a single breast lump, which was first diagnosed to be a malignant lesion. All the results of immunostaining for cytokeratins, GATA3, estrogen receptor, progesterone receptor, HER2, and E-cadherin were negative; hence, the possibility of a breast carcinoma was not considered. However, plasma cell tumors were indicated by the presence of CD138, MUM1, and kappa-light chain markers. In addition, the patient had multiple osteolytic bone lesions, plasma cell infiltration, a monoclonal gammopathy, and signs of renal failure, which considered to be an indication to an extra-medullary breast plasmacytoma secondary to advanced multiple myeloma. This case study emphasizes the necessity of complete histopathological and imaging evolution for proper diagnosis of breast plasmacytoma.
This study aims to synthesis 2-[(dipyrrolidin-1-yl)methylene] malononitrile 2 and identify its crystal structure by X-ray diffraction analysis. 2-[(dipyrrolidin-1-yl)methylene] malononitrile was prepared by a direct displacement of the methylthio group (SMe) in the 2-[bis(methylthio)methylene] malononitrile 1 with pyrrolidine as cyclic secondary amine by conjugating addition-elimination reaction under reflux conditions for two hours. The compound was obtained in high yield (80%). The structure of compound 2-[(dipyrrolidin-1-yl)methylene] malononitrile2 was identified by performing X-ray diffraction analysis. Suitable crystals of compound 2 were grown by slow evaporation of methanol solution of the compound. The compound 2 crystallized in an orthorhombic crystal system with a space group of Pbcn. In the title compound, the two cyanide groups and the two pyrrolidine rings adopted trans configurations across the C2=C3 bond. The bond lengths and angles of the two pyrrolidinyl rings in the compound are within the normal range. The maximum deviation of N5/C2/C3/C4/N5a/C4a is 0.002(1) around C4, and no deviation has been recorded for the fragment N1/N1a/C2/C3 (0.000 (1)°). The dihedral angle between the pyrrolidine ring and N1/N1a/C2/C3 is 33.06(8)°, and the dihedral angle between the pyrrolidine ring and N5/C2/C3/C4/N5a/C4a is 50.57(7)°. The crystal packing is stabilized by two intermolecular and one intramolecular C---H…N hydrogen bonds, which form a one-dimensional polymeric chain along the axis.
The research aims to use climate models to identify how the climate has changed over time in the Zuwara region of Libya, especially the change in the maximum temperature during the twenty-first century, based on the technique of the Statistical Downscaling Model “SDSM”, where it will depend on the maximum temperature data of a weather station, and Zuwara for the period from (1961-1990) (the base period), and forecasting the monthly, quarterly and annual rate of future increase or decrease during the period (2019-2099) according to the (A2a) (B2a) climate change scenarios, which are approved by the Intergovernmental Panel on Climate Change The "IPCC" Intergovernmetal Panel on Climate Change in a report known as "SRES" SPECIAL REPORT EMISSIONS SCENARIOS in the year 2000 to make projections of the climate and the environment based on the amount of greenhouse gas emissions. The results proved that the annual average maximum temperature in the Zuwara region will take an upward trend during the modeling periods compared to the base period (1961-1990). This is consistent with all IPCC scenarios, especially during the second period (2046-2072AD) with an increase of 1.3m◦ over the base period, and this rate maintains its trend of increasing by about 1°C during the period (2073-2099). The results also indicated an increase in the average maximum seasonal temperature according to the two scenarios H3A2a and H3B2a during the winter season in the second period (2046-2072) at a rate of 8°C. In the spring, the rate of change will reach 2◦m. It is expected that the summer will witness a decrease in the maximum average temperature by 5°C, and the same will be the case in the autumn by a rate of 3.3°C in the second period compared to the base period, which threatens the inability of the countries of the world to control and mitigate emissions of greenhouse gases. Key words: climate change/maximum temperature/climate model/climate scenarios/statistical minimization.
The main aim of this thesis is to investigate the factors that could affect the students to adopt e-learning system in Libyan universities. This study is quantitative approach, a questionnaire was adopted from previous studies and distributed among the students to collect the data. The sample of the study consists 365 students from Libya. AMOS software was used to analysis the data. The results indicated that Performance Expectancy, Efforts Expectancy, Facilitating Conditions, Habit and Trust have significant impact on behavioural intention. Moreover, the relationship between Behavioural intention and use behaviour is also significantly positive. However, the relationship of social influence and behavioural intention was not found significant. Finally, the moderation effect was significant and supported between social influence, trust, and Habit with behavioural intention.
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517 members
  • Faculty of Pharmacy
Tahar Abdulaziz Suliman
  • Faculty of Medicine
Asem Khmag
  • Department of Computer System Engineering
Altayeb Elazomi
  • Medical Laboratories Department
Abdulnaser Hamza Fadel
  • Materials Science
SAYEDA ZAINAB, 13, Az Zāwīyah, Zawia, Libya
Head of institution
dr. Meftah Al-Mrabet