Synchronous and Asynchronous Mott Transitions in Topological Insulator Ribbons

We address how the nature of linearly dispersing edge states of two dimensional (2D) topological insulators evolves with increasing electron-electron correlation engendered by a Hubbard like on-site repulsion $U$ in finite ribbons of two models of topological band insulators. Using an inhomogeneous cluster slave rotor mean-field method developed here, we show that electronic correlations drive the topologically nontrivial phase into a Mott insulating phase via two different routes. In a synchronous transition, the entire ribbon attains a Mott insulating state at one critical $U$ that depends weakly on the width of the ribbon. In the second, asynchronous route, Mott localization first occurs on the edge layers at a smaller critical value of electronic interaction which then propagates into the bulk as $U$ is further increased until all layers of the ribbon become Mott localized. We show that the kind of Mott transition that takes place is determined by certain properties of the linearly dispersing edge states which characterize the topological resilience to Mott localization.Comment: 4+ pages, 5 figure

Directed motion of C60 on a graphene sheet subjected to a temperature gradient

Nonequilibrium molecular dynamics simulations is used to study the motion of a C60 molecule on a graphene sheet subjected to a temperature gradient. The C60 molecule is actuated and moves along the system while it just randomly dances along the perpendicular direction. Increasing the temperature gradient increases the directed velocity of C60. It is found that the free energy decreases as the C60 molecule moves toward the cold end. The driving mechanism based on the temperature gradient suggests the construction of nanoscale graphene-based motors

Inequalities in health : social, biological, ethnic and life-course perspectives

There is an unmistakable consistency in differences in risks for morbidity and mortality between social groups. The more advantaged, whether measured in terms of income, education, class, status or ethnicity in general fare better when compared to others, emphasizing the importance of the social environment in determining health in all stages of life. The early stages of life; infancy, childhood, and adolescence are particularly vulnerable – exposures and health in these and later periods of life are dependent on both concurrent social environments and on previous parental life experiences and intergenerational influences. This stresses the need to investigate the development of risk factors and disease across the life course. Affluent and high-income countries are increasingly characterized by widening inequalities in health. Less is known about health differences in ethnic minorities in Sweden compared to similar high- income countries with large immigrant and ethnic minority groups. The importance of intergenerational mechanisms and the psychosocial environment in predicting childhood health was highlighted in studies in this thesis. Children (aged 5-14 years) of parents with lower reported levels of physical activity, higher smoking and alcohol consumption had higher mean BMI and cholesterol levels, independent of parental socioeconomic indicators. Overweight/obese parents also had substantially higher risks for having overweight/obese children (compared to parents of normal BMI, an obese mother had an OR of 4.53 (95% CI 1.98–10.38) for having an overweight/obese child. Similarly, OR for obese fathers was 5.07 (95% CI 2.11–12.20)). Results from studies included in this thesis show that some immigrant groups are at higher risk for health outcomes seen in different stages of the life course. Immigrant parents from Poland, Yugoslavia, Iran, South Asia, East Asia and Sub-Saharan Africa had higher risk for early preterm birth (adjusted RR (95% CI) 1.76, (1.24-2.50), 1.57, (1.31-1.87), 1.67, (1.30-2.14), 1.52, (1.07-2.16), 1.51, (1.08-2.10) and 2.03, (1.32-3.12)) respectively). South Asian, Sub-Saharan African and East Asian immigrant groups had a higher risk for late preterm birth (adjusted RR 1.62 (1.42-1.84), 1.31 (1.08-1.60) and 1.20 (1.06-1.36) respectively). North African/Middle eastern, Somali, and Ethiopian/Eritrean groups had increased RR for postterm birth (adjusted RR 1.31, (1.16-1.47), 2.57 (2.31-2.86), 1.85 (1.67-2.04) respectively). Children aged 4-5 years old, with immigrant parents from Turkey, North Africa, Iran and South America had a higher risk for overweight or obesity compared to children of Swedish born parents. In both studies, socioeconomic indicators did not explain the observed increased risk for either non-term birth or overweight/obesity indicating that other factors that constitute ethnicity may play a role. On the other hand, young Swedish males (ages 18 years) of immigrant parents had lower systolic blood pressure when compared to ethnic Swedish males. The established inverse association between foetal growth and adulthood blood pressure while observed in European-origin men was not seen in non-Europeans. While evidence exists to support that certain ethnic groups suffer disproportionately in risk for some of the adverse health outcomes studied in this thesis, there is also an indication that some ethnic groups are protected from the same. Contrary to expectation, variation in socioeconomic indicators did not explain the observed differences in risk. More studies are needed to understand these observed differences in health and guide better public health intervention for reducing inequalities seen in ethnic minorities

Squamous Cell Carcinoma of the Oral Tongue: a Single Institution Retrospective Cohort Study From Mansoura University Hospital

Background: Egyptian hospital–based statistics showed that head & neck carcinomas represent 18% of all cancers and mostly diagnosed at advanced stages. Our Clinical Oncology & Nuclear Medicine Department of Mansoura Faculty of Medicine serves a large rural area of the Delta region of Egypt. There is no previous study in our institution that focused on oral tongue carcinoma alone. This study aims in establishing the demographics, treatment outcome and prognostic factors of oral tongue squamous cell carcinoma (SCC). Methods: We retrospectively reviewed data of 50 cases with oral tongue SCC treated in our department from January 2014 to December 2016 to evaluate the demography, pathological characteristics, and therapeutic modalities. We estimated the survival rates during the entire follow-up period by the Kaplan–Meier method. The univariate and multivariate Cox proportional hazards analysis were performed for prognostic factors determination. Results: The median follow-up was 30 months (range: 4-45 months). The 3-year overall survival (OS) and disease-free survival (DFS) rates were 68% and 60% respectively. By univariate analysis, both advanced stages (III, IVA) and depth of invasion >0.5 cm were statistically significant as prognostic factors for 3-year DFS and OS rates. DFS rates were 34% vs. 98% for stage III and IVA vs. stage I and II respectively (p = 0.001); 52% vs. 78% for >0.5 cm vs. ≤0.5 cm depth of invasion (p = 0.003). OS rates were 36% vs. 99% for stage III and IVA vs. stage I and II respectively (p = 0.002); 52% vs. 80% for >0.5 cm vs. ≤0.5 cm depth of invasion (p = 0.001). Multivariate analysis of prognostic factors affecting 3-year DFS and OS rates confirmed the statistical significance of the same 2 factors. Conclusions: The majority of our patients were males below 60 years. Tumors were mainly found at stage III and were moderately differentiated. Vascular invasion and lymphatic permeation were uncommon. Staging and tumor invasion depth significantly affected the outcome. The 3-year OS and DFS were 68% and 60% respectively

The Effect of Age and Gender on Fetuin-A and Some Biochemical parameters in Blood Sera of Iraqi patients with T2DM: A comparative study

The serum protein test includes measurement of the level of total protein(albumin, globulin). Fetuin-A is a blood protein made in liver. It can inhibit insulin receptor, enhance insulin sensitivity and make the individuals more likely to develop type 2 diabetes, then disorder in lipid profile (Total cholesterol(TC), low density lipoprotein cholesterol (LDL-c), high density lipoprotein cholesterol (HDL-c), Triglyceride(TG) and very low density lipoprotein cholesterol (VLDL-c) . To evaluate Fetuin-A, total protein, albumin, globulin, HbAlc and lipid profile in 200 adult and elderly Iraqi patients with type 2 Diabetes Mellitus were taken and compare them with 200 subjects as a healthy control. The laboratory analysis(for patients and control ) were performed to determine these parameters .The results show that FBG. HbA1c, Lipid profile for (patients and control) (except HDL-c) were increase with age with a significant difference (p0.05) between male and female. Serum total protein, globulin, Fetuin-A, increase with age while albumin decrease with age(in patients and control)