Abstract: In a sand culture experiment, the seed of the two cultivars (Hysun-33 and SF-187) were exposed to varying levels of nickel (0, 10, 20, 30 and 40 mg Ni L-1). Nickel was applied using NiSO4 and mixed in Hoaglands nutrient solution prior to sowing. Data for various water relation parameters were recorded for five 7-day intervals. Results revealed that changed in water, osmotic and turgor potential more apparent at early growth stages as compared to adult stage. Moreover, osmotic potential was more drastically reduced under nickel stress as compared to water potential. Both sunflower hybrids showed turgor maintenance that indicated nickel tolerance potential of these hybrids. Overall, SF-187 showed less reduction in water potential and greater maintenance of turgor which was attributed to grater ability of this hybrid to accumulate compatible solutes like soluble sugars and proline.

Abstract: From the emotional expression of a face and from the direction of eye gaze we make inferences about another persons focus of interest, their mental state and intentions. This information can be complex but also ambiguous and it would make good adaptive sense for an observer to integrate these different sources of information when making inferences as to whether somebody is looking at something good or bad in the environment. Surprisingly, past research shows that this is not the case. Using the spatial cueing paradigm, we investigated whether the observed direction of eye-gaze and facial expression affect spatial attention, provided the presence of a contextual goal. Results showed evidence of a top-down modulation of visual attention to social cues under these conditions. The implications of these findings for current theories are discussed.

Abstract: With the remarkable advances in the field of medical genetics over the past 50 years, consanguinity has become a source of major scientific and public interest worldwide. Consanguinity is defined as marriage between individuals who are second cousins or more closely related. However, lesser degrees of consanguinity, which are relevant to pregnancy outcomes, have been documented, especially in highly inbred families and tribes. Although it is not a favored religious practice, consanguinity is commonplace (20% to 70% of marriages) in the Middle East. It is deeply rooted in the Arabic culture and has been practiced over many generations not only by Muslims, but also by Christian Arabs. Factors that promote consanguinity in these societies include economic reasons, revolving aroundthe preservation of wealth, psychosocial advantages, and geographical and tribal traditions. Despite their perceived social advantages, consanguineous marriages are associated with a higher frequency of autosomal recessive disorders and multifactorial birth defects. These translate into excess prenatal, perinatal, and postnatal mortality. There is no clear association between parental consanguinity and the frequency of common diseases such as diabetes mellitus, asthma, or adult-onset behavioral and psychiatric disorders. One of the scientifically useful features of consanguinity is that it facilitates homozygosity mapping of disease related genes. Homozygosity mapping in inbred families or isolated populations is a practical strategy for mapping the genes responsible for rare autosomal recessive disorders. The high prevalence of consanguinity in our populations, as well as the large average family size, make it possible to identify inbred families with rare recessive disorders that are large enough to independently establish linkage. In these families, individuals with rare recessive traits are likely to have inherited both copies of the mutated gene from a common ancestor, and are thus identical by descent not only at the trait locus but also at neighboring marker loci. Homozygosity mapping overcomes two major obstacles to gene discovery, locus heterogeneity and variable expressivity. The successful mapping of genes can be used to develop diagnostic tests for carrier identification and for prenatal or preimplantation diagnosis. The identification of the genes after mapping leads to the development of more specific diagnostic tools. The Shafallah Medical Genetics Center has taken advantage of the prevalent consanguinity in our populations, the advances in genotyping and sequencing technology and the robust available analytic tools to initiate gene discovery projects for complex disorders such as epilepsy and autism spectrum disorders. In addition, gene mapping and identification of rare autosomal recessive disorders is an ongoing effort in the center. Collaboration with other teams from Arabic countries has lead to the mapping of five rare autosomal recessive disorder genes. Gene identification by Sanger and Next Generation sequencing is currently ongoing for these five disorders.