Diffusion of small two-dimensional Cu islands on Cu(111) studied with a kinetic Monte Carlo method

Diffusion of small two-dimensional Cu islands (containing up to 10 atoms) on Cu(111) has been studied using the newly developed self-learning Kinetic Monte Carlo (SLKMC) method which is based on a database of diffusion processes and their energetics accumulated automatically during the implementation of the SLKMC code. Results obtained from simulations in which atoms hop from one fcc hollow site to another are compared with those obtained from a parallel set of simulations in which the database is supplemented by processes revealed in complementary molecular dynamics simulations at 500K. They include processes involving the hcp (stacking-fault) sites, which facilitate concerted motion of the islands (simultaneous motion of all atoms in the island). A significant difference in the scaling of the effective diffusion barriers with island size is observed in the two cases. In particular, the presence of concerted island motion leads to an almost linear increase in the effective diffusion barrier with size, while its absence accounts for strong size-dependent oscillations and anomalous behavior for trimers and heptamers. We also identify and discuss in detail the key microscopic processes responsible for the diffusion and examine the frequencies of their occurrence, as a function of island size and substrate temperature.Peer reviewe

Retinal blood vessels extraction using probabilistic modelling

© 2014 Kaba et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This article has been made available through the Brunel Open Access Publishing Fund.The analysis of retinal blood vessels plays an important role in detecting and treating retinal diseases. In this review, we present an automated method to segment blood vessels of fundus retinal image. The proposed method could be used to support a non-intrusive diagnosis in modern ophthalmology for early detection of retinal diseases, treatment evaluation or clinical study. This study combines the bias correction and an adaptive histogram equalisation to enhance the appearance of the blood vessels. Then the blood vessels are extracted using probabilistic modelling that is optimised by the expectation maximisation algorithm. The method is evaluated on fundus retinal images of STARE and DRIVE datasets. The experimental results are compared with some recently published methods of retinal blood vessels segmentation. The experimental results show that our method achieved the best overall performance and it is comparable to the performance of human experts.The Department of Information Systems, Computing and Mathematics, Brunel University

Planning of Sustainable Industrial Zones and Means of Achieving them in Iraq

The development of industrial activity in cities and regions is one of the most distinctive features of postmodern urban planning. The industry in all its branches is considered one of the most important economic activities in cities, which is the main engine of economic life and the driving force of development at all levels. This development has been accompanied by the negative effects of this economic activity on ecosystems and on human life in its various aspects, namely, environmental pollution in various ways, depletion of renewable and depleted natural resources, and the serious consequences of climate change, environmental degradation and Collapse. Hence the need to find solutions that allow the continuation of industries because of the importance of human life and to overcome the problems resulting from them and reduce them as much as possible The emergence of the concept of sustainability as a solution to this problem. This paper discusses the theme of sustainable industry, sustainable industrial zone planning, global experiences and identification of deliberatestrategies for sustainability, As well as trends in Iraq towards the establishment of green industrial cities, And their analysis and knowledge of their shortcomings in comparison to international experiences. And recommend some policies to achieve sustainability

Fibers Direction Effect on Tensile Elasticity of Epoxy Composites Using Computer modeling

In this research a sample of glass fiber reinforced Epoxy Composite was subjected to a tensile load to study the effect of fiber directions on the tensile elasticity theoretically using Finite Element Method (FEM) . MSC-NASTRAN computer package was used for the purpose of this study. Tensile test was done on the design samples when fibers angled with the Load direction at 0o ,45o and 90o in order to find out the direction which provides the best mechanical properties. Through the tests result and color spectrum analysis, we found that 0o angle provides the best properties, followed by 45o angle, while at 90o angle shows lowest value of elasticity modulus

Assessment the Effect of Some Reagents on the Planktonic Cells and Biofilms of Red Complex Periodontal Pathogens

The current study aimed to investigate the effectiveness of four regents; two naturals, olibanum and alum, and two standards, ciprofloxacin (CIP) and chlorhexidine (CHX) to affect the growth and biofilm of three types of periodontal pathogens, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, "the red complex group". Clinical isolates of the red complex pathogens were isolated from chronic periodontitis. They were identified by phenotypic properties and molecular method. The inhibitory activity of the four reagents was tested by microdilution method. Minimal inhibitory concentration (MIC) on the bacterial plankton and minimal biofilm inhibitory concentration (MBIC) on biofilm of the four reagents in a single and combinational use was determined on mono- and polymicrobial populations. Simple linear regression modeling was used to explore the effect of each reagent and determine MICs and MBICs. All reagents showed inhibition activity against the growth of mono- and polymicrobial planktonic population. MIC values on polymicrobial growth were higher than on monomicrobial growth and MBICs were much higher. All reagents had antibacterial activity on a monomicrobial biofilm with greater significant effect on T. denticola then T. forsythia and P. gingivalis. On polymicrobial biofilm, just olibanum continued showing its effect whilst CHX was less effect and both alum and CIP had no effect. Combinational use with Olibanum encouraged the effect of other regents on polymicrobial biofilm. This combination is a promising medicated preparation to combat the subgingival plaque of red complex pathogens

Prevalence of Osteoporosis in 100 Iraqi Patients with Systemic Lupus Erythematosus: A Case Control Study

Back ground: In recent years, survival of patients with systemic lupus erythematous (SLE) has raised significantly so long-term complications, as osteoporosis, are currently of major importance. Objective: To assess the prevalence of osteoporosis in Iraqi patients with SLE. Patients and Methods: This case control study was conducted on 100 SLE patients and 100 healthy controls matched in age, sex, and body mass index. Bone mineral density (BMD) obtained at the lumber spine (L1-L4) and right and left femurs using dual energy X-ray absorptiometry (DXA) machine (Dexxum). Osteoporosis was diagnosed according to WHO guidelines criteria for diagnosis of osteoporosis and Z-scores was used in premenopausal women and men younger than 50 years. Results: Mean age of SLE patients was 32.01±10.14 years and 32.46±6.29 years in the control group. Females represented 91% of patients and 92% of controls. The mean BMI of patients was 27.41±6.04 kg/m2 compared to 28.8±5.26 kg/m2 of controls. There was no statistical significant differences between both groups in demographic characteristics (P>0.05). BMD at lumbar spine was significantly lower in SLE patients than controls (82(82%) vs 61(61%), p< 0.001, OR (95%CI): 3.04(1.59-5.81).Of those patients with low BMD, 46% had osteoporosis. Additionally, BMD at total femur was significantly lower in SLE patients than controls (59 (59%) vs 24(24%), p<0.001, OR (95%CI): 4.56(2.48-8.37). Of those patients with low BMD at total femur, 15 (15%) had osteoporosis. Multiple logistic regression analysis showed non-significant association between low BMD in SLE patients and various baseline characteristics (P>0.05). Conclusions: Prevalence of osteoporosis in Iraqi patients with SLE was 46% at lumbar spine and 15 % at total femur. This may suggest to do early screening for low BMD in patients with SLE for early diagnosis and appropriate treatment. Keywords: SLE, Osteoporosis, Dual x-ray absorptiometry, Bone mineral densit

Salivary microRNA 155, 146a/b and 203: A pilot study for potentially non-invasive diagnostic biomarkers of periodontitis and diabetes mellitus

Dysregulated expression of MicroRNAs (miRNAs) plays substantial role in the initiation and progression of both diabetes and periodontitis. The aim of the present study was to validate four miRNAs in saliva as potential predictive biomarkers of periodontal disease among patients with and without diabetes mellitus (DM). MiRNAs were extracted from the saliva of 24 adult subjects with DM and 29 healthy controls. Each group was subdivided into periodontally healthy or having periodontitis. In silico analysis identified 4 miRNAs (miRNA 155, 146 a/b and 203) as immune modulators. The expression of miRNAs-146a/b, 155, and 203 was tested using quantitative PCR. The expression levels in the study groups were compared to explore the effect of diabetes on periodontal status and vice versa. In our cohort, the four miRNAs expression were higher in patients with periodontitis and/or diabetes. miRNA-155 was the most reliable predictors of periodontitis among non-diabetics with an optimum cut-off value of < 8.97 with accuracy = 82.6%. MiRNA 146a, on the other hand, was the only reliable predictor of periodontitis among subjects with diabetes with optimum cut-off value of ≥11.04 with accuracy = 86.1%. The results of the present study concluded that MiRNA-146a and miRNA155 in saliva provide reliable, non-invasive, diagnostic and prognostic biomarkers that can be used to monitor periodontal health status among diabetic and non-diabetic patients

Prevalence and Predictors of Pulmonary Arterial Hypertension in a Sample of Iraqi Patients with Systemic Sclerosis: A Cross-Sectional Study

Background: Pulmonary arterial hypertension (PAH) is now the most frequent cause of death in systemic sclerosis (SSc). Aims: The aims of the present study were to evaluate the prevalence of pulmonary arterial hypertension (PAH) and predictors in SSc among Iraqi patients. Materials and Methods: A cross-sectional study conducted on 56 patients with SSc diagnosed according to the criteria developed by the American College of Rheumatology. Baseline characteristics [age, sex, body mass index (BMI), duration of SSc, type of SSc, duration of Raynaud’s phenomenon, and presence of telangiectasia] were documented.  Antiscleroderma 70 (anti-SCL70) and anticentromere antibodies were measured. Doppler echocardiography was done to diagnose PAH. A risk score was obtained from 7 criteria, namely: Anti-Centromere Ab, Limited disease type, short duration of Raynaud's phenomena (&lt;2.5 years), older age group (40+ years), absence of Telangiectasia, female gender, and absence of anti SCL70 Ab.  Results: We found that PAH was present in 11 (19.6%) SSc patients with a 95% confidence interval of (9.2% to 30.0%). Risk score in addition to anti-centromere antibodies were enough to diagnose PAH with accuracy level of 89.3%. Conclusions: PAH in SSc occurs in significant proportion of patients. Risk score and anti-centromere antibodies had high accuracy level in predicting PAH. Screening of patients with SSc for PAH will help in early diagnosis and appropriate timely therapeutic intervention before significant endorgan damage occurs. Key words Systemic sclerosis. Connective  tissue. Pulmonary hypertension