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Abstract-Teacher immediacy (verbal and non-verbal)remains an important factor towards prompting efficient pedagogical approaches. Whilst teacher immediacy in a classroom setting is important, there is growing awareness about the importance of the construct in a virtual setting as education shifts from explicit conventional face-to-face teaching and learning to a blended environment which includes distance education. This paper attempts to generate some understandings about the correlation between teacher immediacy, both verbal and non-verbal, and students' active participation and satisfaction in a distance education learning environment. This paper considers, in a preliminary research framework, a Saudi university which offers a range of distance education courses as an initial cohort from which to generate such understandings. Students' opinions, perceptions, and reported satisfaction were captured through utilising a structured questionnaire completed by 413 participants, enrolled in a variety of distance education courses offered by the aforementioned university. This study found that there was significant correlation between the overall adopted teacher immediacy (verbal and non-verbal) and students' overall online participation and satisfaction in the investigated distance education courses. In terms of gender differences, male participants have higher willingness to participate than female participants within the perceived immediacy behaviours. On the other hand, female participants were more satisfied in terms of communication than male participants within the perceived "e-immediacy" behaviours. These results serve as a prompt for further research on teacher immediacy in the rapidly developing and increasing virtual education domain in a global and connected world.Index Terms-Distance education, teacher immediacy, e-immediacy, verbal immediacy, non-verbal immediacy, students' satisfaction, students' online participation, students' communication satisfaction. I. INTRODUCTIONTeacher immediacy has been a topic of research and interest in conventional (face-to-face) classroom settings. Teacher immediacy-both verbal and non-verbal-focuses mainly on creating a close collaborative communicative environment, where immediacy as a term is defined as ‗the relationship between the speaker and the objects he or she communicates about' [1]. A number of scholars perceived teacher immediacy as the reduction of psychological or [5]. Recent research reported that university lecturers who employ immediacy -including lecturers' warmth and approachability-in their teaching and learning practice experience an increased level of students' participation and enjoy a greater ‗breadth' of such participation [5] In a digital and internationalised 21 st century, universities strive to reposition themselves into offering distance education [6]. In a virtual learning environment, physical separation is one of the characteristics of distance education. Regardless of the advantages physical separation might bring about (flexibility, sav...

Understanding salt tolerance in tomato (Solanum lycopersicum L.) landraces will facilitate their use in genetic improvement. The study assessed the morpho-physiological variability of Hail tomato landraces in response to different salinity levels at seedling stages and recommended a tomato salt-tolerant landrace for future breeding programs. Three tomato landraces, Hail 548, Hail 747, and Hail 1072 were tested under three salinity levels: 75, 150, and 300 mM NaCl. Salinity stress reduced shoots’ fresh and dry weight by 71% and 72%, and roots were 86.5% and 78.6%, respectively. There was 22% reduced chlorophyll content, carotene content by 18.6%, and anthocyanin by 41.1%. Proline content increased for stressed treatments. The 300 mM NaCl treatment recorded the most proline content increases (67.37 mg/g fresh weight), with a percent increase in proline reaching 61.67% in Hail 747. Superoxide dismutase (SOD) activity decreased by 65% in Hail 548, while it relatively increased in Hail 747 and Hail 1072 treated with 300 mM NaCl. Catalase (CAT) activity was enhanced by salt stress in Hail 548 and recorded 7.6%, increasing at 75 and 5.1% at 300 mM NaCl. It revealed a reduction in malondialdehyde (MDA) at the 300 mM NaCl concentration in both Hail 548 and Hail 1072 landraces. Increasing salt concentrations showed a reduction in transpiration rate of 70.55%, 7.13% in stomatal conductance, and 72.34% in photosynthetic rate. K+/Na+ ratios decreased from 56% for 75 mM NaCl to 85% for 300 mM NaCl treatments in all genotypes. The response to salt stress in landraces involved some modifications in morphology, physiology, and metabolism. The landrace Hail 548 may have better protection against salt stress and observed protection against reactive oxygen species (ROS) by increasing enzymatic “antioxidants” activity under salt stress.

Landraces are valuable sources of genetic characteristics, which are of plant breeders’ interest to include in breeding programs for crop improvement. We assess the inter- and intra-genetic variability among 96 accessions representing three Hail tomato landrace using DNA-based marker sequence-related amplified polymorphism (SRAP). Seven SRAP primer combinations generated 55 alleles with a polymorphism of 100%, and an average of 7.86 polymorphic alleles per pair of primers. All primers showed an average of 0.68 polymorphic information content (PIC) value and discrimination power (DP) of 14.29. Principal coordinate analysis (PCoA) confirmed the clustering produced via the UPGMA similarity dendrogram allowed for the grouping of the 96 accessions according to its gene bank accession numbers and showed relatively good separation between landraces. A similarity value ranged from 0.04 to 1.0 among accessions of Hail 747, 0.05 to 1.0 in Hail 1072, and from 0.16 to 0.92 in Hail 548. These results showed the landraces harbor a wide range of genetic diversity at both inter and intra-variation levels. AMOVA showed that most of the genetic variation was because of differences within populations (87%). Tomato Hail landraces have well-differentiated genetic populations and admixtures, where Hail 747 formed their separate group, and both Hail 548 and Hail 1072 were admixed, and some accessions showed more diversity pattern. We have to take the SRAP technique’s effectiveness in the study of genetic variability among and within landraces into consideration in the tomato-breeding programs through marker-assessed selection.

The present study aimed to evaluate the prevalence of the asymptomatic carriers of hepatitis B surface antigen among pilgrims; to demonstrate its distribution in different nationalities, age groups, and gender. The prevalence of hepatitis B surface antigen, among 982 apparently healthy pilgrims was determined using enzyme-linked immunosorbent assay. Positive samples were confirmed by the MiniVIDAS system. Positivity rate was 4.1% and was higher in males (87.5%), age group of 40-59 years (60%) and in Nigerian pilgrims (8 pilgrims). All samples were also analyzed for antibodies against hepatitis C virus using enzyme-linked immunosorbent assay. Only one sample was positive for both hepatitis B surface antigen and hepatitis C virus antibodies. It was concluded that there was an intermediate endemicity (4.1%) with significant (P < 0.05) difference between the rate in the different age groups but not between the rate in males and females nor in nationalities. Nationalities with low frequencies of pilgrims should not be neglected as a source of infection. No association between the presence of hepatitis B surface antigen and hepatitis C virus antibodies. Performance of this study (with genotyping) on a large scale and genotyping of the 40 positive samples is recommended.