A critical review on the contributions of chemical and physical factors toward the nucleation and growth of large-area graphene

Since the first isolation of graphene over a decade ago, research into graphene has exponentially increased due to its excellent electrical, optical, mechanical and chemical properties. Graphene has been shown to enhance the performance of various electronic devices. In addition, graphene can be simply produced through chemical vapor deposition (CVD). Although the synthesis of graphene has been widely researched, especially the CVD growth method, the lack of understanding of various synthetic parameters still limits the fabrication of large-area and defect-free graphene films. This report critically reviews various parameters affecting the quality of CVD grown graphene to understand the relationship between these parameters and thechoice of metal substrates and to provide a point of reference for future studies of large-area, CVD-grown graphene

Seroprevalence of cytomegalovirus Antibodies among pregnant women and it’s correlation with spontaneous abortion in Khartoum state

Background: Cytomegalovirus is a common virus that infects most people at some time during their lives. It becomes dormant for a while and may reactivate later. In pregnant women, intrauterine infection may be  associated with congenital abnormalities, intrauterine growth retardation and intrauterine death of the fetus as well as late sequelae such as  developmental delay, blindness and congenital deafness.Objectives: The aim of this study was to determine the seroprevalence of CMV infection among women presenting with spontaneous abortion to major hospitals in Khartoum State and to find out the correlation between CMV infection and spontaneous abortion in the group under study.Methodology: In this study a total of 180 spontaneously aborted females, and 80 normally delivered females (control) were included. Three mls of venous blood were collected from each subject under study in a plain  container allowed to clot and after clot retraction centrifuged at 4000rpm. The sera were then separated and stored at -20c0 in a deep freezer. The stored sera were tested for CMV IgG and IgM antibodies using Enzyme Linked Immunosorbent Assay (BIOTECH –ENGLAND).Results: In the case group, 176 (97.8%) women were positive for Anti-CMV IgG and 69 (38.3%) for Anti-CMV IgM. The CMV antibodies significantly co related with increasing age (P-value = -0.0185), the number of abortion (P-value = -0.0177) and congenital malformation in children (P value= 0.037).Conclusion: Seroprevalence of CMV antibodies was found to be 97.8% and 38.3% for IgG & IgM respectively. There was significant association  between CMV infection and frequency of abortion, age and congenital  malformation in children.Key words: CMV, seroprevalnce, pregnancy, spontaneous abortion, Suda

Predicting Distribution of Aedes Aegypti and Culex Pipiens Complex, Potential Vectors of Rift Valley Fever Virus in Relation to Disease Epidemics in East Africa.

The East African region has experienced several Rift Valley fever (RVF) outbreaks since the 1930s. The objective of this study was to identify distributions of potential disease vectors in relation to disease epidemics. Understanding disease vector potential distributions is a major concern for disease transmission dynamics. DIVERSE ECOLOGICAL NICHE MODELLING TECHNIQUES HAVE BEEN DEVELOPED FOR THIS PURPOSE: we present a maximum entropy (Maxent) approach for estimating distributions of potential RVF vectors in un-sampled areas in East Africa. We modelled the distribution of two species of mosquitoes (Aedes aegypti and Culex pipiens complex) responsible for potential maintenance and amplification of the virus, respectively. Predicted distributions of environmentally suitable areas in East Africa were based on the presence-only occurrence data derived from our entomological study in Ngorongoro District in northern Tanzania. Our model predicted potential suitable areas with high success rates of 90.9% for A. aegypti and 91.6% for C. pipiens complex. Model performance was statistically significantly better than random for both species. Most suitable sites for the two vectors were predicted in central and northwestern Tanzania with previous disease epidemics. Other important risk areas include western Lake Victoria, northern parts of Lake Malawi, and the Rift Valley region of Kenya. Findings from this study show distributions of vectors had biological and epidemiological significance in relation to disease outbreak hotspots, and hence provide guidance for the selection of sampling areas for RVF vectors during inter-epidemic periods

A Survey Of Teacher and Student Beliefs in Singapore's Polytechnics

Abstract: Language teaching has been focused mainly on teachers' classroom actions and behaviours and their effects on learners. It is acknowledged that teacher knowledge and beliefs form the underlying framework guiding a teacher's classroom practices. However, not to be ignored are learners' beliefs about teaching and learning which influence how they approach learning. Thus, teachers need to be informed about learners' beliefs so that they can better understand and manage their teaching as well as their students learning. The purpose of this study is to investigate similarities and differences between teachers' and students' beliefs. Sixty-two English language teachers and 164 students from the four polytechnics in Singapore participated in the study. Data for this study came from these teachers' and students' responses to a survey questionnaire designed to elicit information about some aspects of their beliefs. In this paper, we will report on some pedagogically interesting differences in certain areas of teachers' and students' beliefs (e.g., What constitutes good teachers/learners, why learners fail to learn English). We will also discuss the implications of these differences for language teaching and learning.

Aligning Artificial Intelligence with Climate Change Adaptation in Egypt

Abstract: One of the frequently witnessed barriers to accelerating action on climate change is related to the construction of data bases, variables, and models as well as data extraction. According to the Grantham Research Institute on climate change and the environment, several subfields of Artificial Intelligence identify patterns to support the completion of specific tasks towards combating climate change such as; gathering, completing, and interpreting large, and complete datasets by making it possible to enhance data-driven decision-making for climate action. However, the negative side of AI was also recognized. Learning algorithms to understand how AI’s climate impact goes beyond its emissions and how technological advancements facilitates the process of combating climate change, examining the confluence between AI and climate change and the positive and negative implications of using high level of technology and its carbon effects are essential in this study .This paper will conduct the qualitative analysis method through relying on secondary data sources such as; reports on climate change and AI, national academies press, theories including; Meso, Micro, and Macro theories, gathering data from Ministry of Communication and Information Technology, Ministry of Environment, as well as taking into consideration the importance of using declarations of ethical principles in relation to climate change. Presenting a comprehensive point of view regarding the negative and positive effects of using Artificial Intelligence to combat Climate Change in Egypt. This paper argues that Artificial Intelligence has an effect on climate change globally

Correlation between a single nucleotide polymorphism (G/T at nt –88) in the Mx1 gene promoter and the response to interferon therapy for hepatitis C virus in Egyptian patients

Interferon used in the treatment of hepatitis C virus (HCV) patients stimulates the expression of a number of host genes encoding enzymes with antiviral activities, including myxovirus resistance gene- 1 (Mx1). Mx1 gene was found to have a single nucleotide polymorphism (SNP) at position -88 in the promotor region that affect the expression of Mx 1 protein and was suggested to be associated with the response of HCV. In this study, we assessed the relation between the SNP in the Mx1 gene and the responsiveness of Egyptian HCV patients to pegylated interferon and ribavirin treatment along with other host-related and virus-related predictors of treatment outcome. We genotyped the biallelic G/T SNP in the promoter region of Mx1 gene at position -88 from the transcription start site by restriction fragment length polymorphism (RFLP) in 42 interferon treatment-naïve Egyptian patients that were treated with pegylated interferon and ribavirin. We found that Mx1 nt-88 SNP is not significantly correlated to achieving sustained virological response (SVR) after pegylated interferon alpha and ribavirin combined treatment. We conclude that Mx1 gene polymorphism at codon nt-88 cannot be considered as biological marker to potentially identify responders and non-responders of HCV patients to achieve a sustained virological response to treatment with interferon (IFN) in combination with ribavirin.Key words: Hepatitis C virus (HCV), interferon (IFN), myxovirus resistance protein (Mx1 protein), myxovirus resistance gene-1 (Mx1 gene), single nucleotide polymorphism (SNP)

Characterizing genomic alterations in cancer by complementary functional associations.

Systematic efforts to sequence the cancer genome have identified large numbers of mutations and copy number alterations in human cancers. However, elucidating the functional consequences of these variants, and their interactions to drive or maintain oncogenic states, remains a challenge in cancer research. We developed REVEALER, a computational method that identifies combinations of mutually exclusive genomic alterations correlated with functional phenotypes, such as the activation or gene dependency of oncogenic pathways or sensitivity to a drug treatment. We used REVEALER to uncover complementary genomic alterations associated with the transcriptional activation of β-catenin and NRF2, MEK-inhibitor sensitivity, and KRAS dependency. REVEALER successfully identified both known and new associations, demonstrating the power of combining functional profiles with extensive characterization of genomic alterations in cancer genomes

Corn and potato starch as an agar alternative for Solanum tuberosum micropropagation

Potato single nodes were subcultured onto fresh MS medium gelled with 0, 1 and 2 g/l of agar + 40, 50 or 60 g/l of commercial corn and potato starch (CS or PS, respectively). After 4 weeks of culture, the pH of medium supplemented with 50 or 60 g/l of CS or 60 g/l of PS was significantly decreased to 3.91 - 4.00. This reduction coincided with a significant increment in electric conductivity (EC) which was 172 - 214 ìmhos/cm-1 for media containing 50 or 60 g/l of CS, or 60 g/l of PS. Corn and potato starch had no significant effect in plantlet height nevertheless, they significantly increased the number of shoots/explant over the control treatment (2.5) which had 7 g/l of agar. The highest number ofshoots/explant (6.8) was achieved in medium with 50 or 60 g/l of PS + 1 g/l of agar. Plantlets developed on media with 40 g/l of CS or PS had higher shoot fresh and dry weight (p < 0.5) compared to those in thecontrol one. Media with 50, 60 g/l of PS or 60 g/l of CS and 50 g/l of CS + agar at 1 g/l significantly enhanced the percentage of dry weight. Moreover, 92 - 98% of plantlets were acclimatized to the greenhouse conditions regardless the type of gelling agent. The results suggest that the combination of agar and PS or CS could offer a firm support for plant tissues and could be successfully used for potato micropropagation