Occurrence and sources of aliphatic hydrocarbons in surface soils from Riyadh city, Saudi Arabia

AbstractSoil particles contain a variety of anthropogenic and natural organic components derived from many sources such as industrial and traffic fossil fuel emissions and terrestrial biota. The organic contents of soil and sand from the Arabian region have not fully characterized. Thus, samples of fine soil particles (sieved to <125μM) were collected from the Riyadh area in November 2006 (late summer) and February 2007 (late winter). The samples were extracted with a mixture of dichloromethane/hexane and analyzed by gas chromatography–mass spectroscopy (GCMS) in order to characterize the chemical composition and sources of aliphatic hydrocarbons. The results showed that both anthropogenic and natural biogenic inputs were the major sources of the aliphatic hydrocarbons in these extracts. Vehicular emission products and discarded plastics were the major anthropogenic sources in the fine particles of the soils and ranged from 64% to 96% in November 2006 and from 70% to 92% in February 2007. Their tracers were n-alkanes, hopanes, sterane, plasticizers and UCM. Vegetation was also a major natural source of hydrocarbon compounds in samples ranging from ∼0% to18% in November 2006 and from 1% to 13% in February 2007 and included n-alkanes and triterpenoids

Educating Students with Visual Disability in the State of Kuwait: Literature Review and Recommendations

The primary purpose of this study was to review the educational process of student with visual disability in Kuwait. The visual impairment is one of the special education classes that attracted the attention and attention of researchers and educators. Students with visual impairment show various educational and psychological needs, and the assessment determines the nature of these special needs. Meeting these needs requires specialized educational programs and a variety of services to achieve their maximum potential optimal level of adjustment. The present study is considered a theoretical study. The review indicated that students with visual disability have a wide range of characteristics and specialized needs. Visual disability negatively affected students’ especially academic achievement, nonverbal communication, as well as psychosocial development. These needs require special services in order to meet them. The study ended by offering a number of conclusions and recommendations for better education of this group of disability. Basically, there is a need to rethink with the educational procedures used and develop their education

The Psychological and Social Effects of COVID-19 Outbreak on Persons With Disabilities

The current study aimed to describe the psychological and social effects of COVID-19 Outbreak on persons with disabilities in the State of Kuwait. The study sample consisted of 150 participants. To achieve the goals of the study, the two researchers constructed the study tool which included two dimensions, one for psychological effects and the other for social effects. The validity and reliability of study tool were achieved. The results reported that COVID-19 causes psychological and social effects on persons with disabilities, and these impacts vary according to the type of disability. Also, the vast majority of participants were reported that the virus caused a change in their daily social routine, as well as negatively affected their participating in social activities. In addition, many of the participants were stated fear of spread the virus and stigma if infected. The study recommended the necessity of providing psychological, social and health support to persons with disabilities

Using Literature in Pedagogical Contexts as a Solution for the EFL Learners’ Problems in Sudan

This paper is an attempt to answer several open-ended questions regarding the pedagogical values of the exploitation of literature in promoting EFL learning at the different educational levels in the Sudan. These answers are grounded on a system of research methods which have recently been introduced by the new trends in stylistics. Apart from the introduction and the conclusion, this paper consists of the background of the topic which reviews a number of issues concerning the merits, role, procedures and activities of using literature in EFL contexts. The paper also provides a summary of research in the theories and approaches of literature in EFL contexts. Afterwards, the paper focuses on the tools of the stylistic methods and techniques to be applied in the study of every literary text. Two English poems were specifically selected for placing the stylistic analysis principles in the context of patterns of meaning to be stylistically analyzed. The examples were selected for the investigation of the poetic devices which are commonly used in a literary text. Finally, the paper tries to summarize the pedagogical values gained by poetry stylistic analysis in learning the linguistic aspects of a literary text. This paper focuses on the most effective pedagogical technique and content as a contribution to the quality of education in the Sudan

Evaluation of Some Virulence Factors of Methicillin and Vancomycin Resistant Staphylococcus epidermidis Isolated from Cheese and Human Samples

Biofilm formation and enterotoxin production represent major virulence factors of S. epidermidis. Also, biofilm formation is greatly associated with multidrug resistance. So the objective of the present study was to expand the current knowledge regarding the importance and virulence of methicillin and vancomycin resistant S. epidermidis originated from dairy food, food handlers and patients in a hospital, and highlight the possible transmission through foods and food handlers. Biofilm formation was evaluated phenotypically by the tube method and microtiter plate method and genotypically through detection of icaA and icaD genes, while S. epidermidis isolates were investigated for potential enterotoxin production through detection of enterotoxin encoding genes (sea, seb and sec). Among the investigated isolates, phenotypic and genotypic biofilm formation was confirmed in 78.4 and 66.7 % of the isolates, respectively. Regarding enterotoxin encoding genes, it was found that seb gene was the only prevailing gene in the three categories of samples with an incidence of 27.5 %. The findings of this study illustrated the prominent role that played by food handlers in transmission of virulent S. epidermidis to food and subsequently patients

Measles in Sudan: Diagnosis, Epidemiology and Humoral Immune Response

Despite the availability of safe and effective live attenuated vaccines, measles remains endemic in many developing countries. Little is known about the pathogenesis of measles virus (MV) infections in the areas of itsendemicity, largely due to the limited infrastructure and political instability. Whereas measles in industrialised countries is often considered an “innocent” childhood disease, measles case-fatality rates are often well above 1% in developing countries, and can be even higher in outbreak situations (5). Oneexplanation for this observation is that measles is associated with a transient immunosuppression resulting in an increased susceptibility to other infectious agents: the infectious pressure of many human pathogens is substantially higher in developing countries than in the industrialised world. Incombination with vitamin deficiencies (e.g. vitamin A) and inadequate case management this increases the risk of MV infection developing into a serious life-threatening disease (3). However, prior to or co-infections with otherpathogens could also play a role in modifying the specific immune responseto MV infection. In particular the high prevalence of parasitic infections inmany developing countries could affect the development of the cellular immune system towards a dominance of T-helper (Th) cells producing type 2 cytokines such as IL-4, IL-5 IL-10 and IL-13. Such responses have beenassociated with immunosuppression (197), and counterbalance Th responsesproducing type 1 cytokines (such as IL-12 and interferon-γ) which sustaincytotoxic T cell (CTL) response and have been associated with clearance ofMV infection (198). Towards the control and eventual eradication of measles more insight will be required in the pathogenesis of measles in areas of its endemicity. However, another reason to study measles in these regions is that it allows the development and validation of alterna

Effect of fiber loading on mechanical and morphological properties of cocoa pod husk fibres reinforced thermoplastic polyurethane composites

In this study, cocoa (Theobroma cacao) pod husk (CPH) fiber reinforced thermoplastic polyurethane (TPU) was prepared by melt compounding method using Haake Polydrive R600 internal mixer. The composites were prepared with different fiber loading: 20%, 30% and 40% (by weight), with the optimum processing parameters: 190 °C, 11 min, and 40 rpm for temperature, time and speed, respectively. Five samples were cut from the composite sheet. Mean value was taken for each composite according to ASTM standards. Effect of fiber loading on mechanical (i.e. tensile, flexural properties and impact strength) and morphological properties was studied. TPU/CPH composites showed increase in tensile strength and modulus with increase in fiber loading, while tensile strain was decreasing with increase in fiber loading. The composite also showed increase in flexural strength and modulus with increase in fiber content. Impact strength was deteriorated with increase in fiber loading. Morphology observations using Scanning Electron Microscope (SEM) showed fiber/matrix good adhesion

Kepemimpinan Kepala Sekolah dalam Pembentukan Karakter Islami Peserta didik

Education in general with national education has the same function and purpose in shaping good character / personality for students. This shows how serious the government is in realizing character education in this beloved country. Building character is not an instant job and by one institution alone. A person's character is formed as the cumulative impact of lessons learned from the journey of learning and working throughout one's life involving various institutions, both formal, informal, and non-formal education where a person finds himself from infancy to adulthood through proper education (Joni, 2008). In the world of education, the principal plays an important role in shaping the character of students. Because decisions will be made based on orders from the principal. This research uses the library research method because it makes it easier for us to get information, and this information can be obtained from scientific books, research reports, scientific essays, theses and dissertations, regulations, provisions, yearbooks, encyclopedias and other sources. other written and electronic sources