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Laser diagnostics of pulverized coal combustion in O<inf>2</inf>/N<inf>2</inf> and O<inf>2</inf>/CO<inf>2</inf> conditions: velocity and scalar field measurements
Optical diagnostic techniques are applied to a 21 kW laboratory-scale pulverized coal–methane burner to map the reaction zone during combustion, in mixtures with varying fractions of O_2, N_2 and CO_2. Simultaneous Mie scatter and OH planar laser-induced fluorescence (PLIF) measurements have been carried out to study the effect of the oxidizer/diluent concentrations as well as the coal-loading rate. The spatial distribution of soot is captured using laser-induced incandescence (LII). Additionally, velocity profiles at selected axial locations are measured using the pairwise two-dimensional laser Doppler velocimetry technique. The OH PLIF images capture the reaction zones of pilot methane–air flames and the variation of the coal flame structure under various O_2/CO_2 compositions. Coal particles devolatilize immediately upon crossing the flame interface, so that the Mie scatter signal almost vanishes. Increasing coal-loading rates leads to higher reaction rates and shorter flames. LII measurements show that soot is formed primarily in the wake of remaining coal particles in the product regions. Finally, differences in the mean and RMS velocity field are explained by the combined action of thermal expansion and the changes in particle diameter between reacting and non-reacting flows.This work is supported by EPSRC research Grant (#EP/G062153/1). Yi Gao is supported by EPSRC Grant (#EP/K02924X/1), S. Lowe acknowledges support through an EPSRC DTA grant, M. Kamal is supported by University of Engineering and Technology Peshawar (Pakistan), and Bo Tian acknowledges support from CSC.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00348-015-1965-
Loss of CSMD1 expression disrupts mammary duct formation while enhancing proliferation, migration and invasion
The CUB and sushi multiple domains 1 (CSMD1) gene maps to chromosome 8p23, a region deleted in many cancers. Loss of CSMD1 expression is associated with poor prognosis in breast cancer suggesting that it acts as a tumour suppressor in this cancer. However, the function of CSMD1 is largely unknown. Herein, we investigated CSMD1 functions in cell line models. CSMD1 expression was suppressed in MCF10A and LNCaP cells using short hairpin RNA. Functional assays were performed focusing on the 'normal' MCF10A cell line. Suppression of CSMD1 significantly increased the proliferation, cell migration and invasiveness of MCF10A cells compared to shcontrols. shCSMD1 cells also showed significantly reduced adhesion to Matrigel and fibronectin. In a three-dimensional Matrigel model of MCF10A cells, reduced CSMD1 expression resulted in the development of larger and more poorly differentiated breast acini-like structures that displayed impaired lumen formation. Loss of CSMD1 expression disrupts a model of mammary duct formation while enhancing proliferation, migration and invasion. Our data suggest that CSMD1 is involved in the suppression of a transformed phenotype
Maternal risk factors in young Egyptian mothers of Down syndrome
Introduction: We investigated the possible maternal risk factors that mayincrease the incidence of Down syndrome (DS) in young Egyptian mothers(younger than 35 years) especially methylene tetrahydrofolate reductase(MTHFR) enzyme C677T polymorphism.Subjects and Methods: The study included 200 mothers of karyotypicallyascertained non-disjunction DS attending Genetics clinic, Children’s hospital, Ain Shams University (100 mothers were < 35 years and 100 mothers ≥ 35 years). 50 mothers of none-DS children served as a control group. For all cases, history was taken laying stress on: Parental ages at conception, maternal grandparent’s ages at conception of mother, DS birth order, history of oral contraceptive use 6 months before conception, genital infection, vitamin supplementation and smoking or exposure to irradiation.Results: MTHFR C677T mutational analysis was done to twenty DS motherswith ages ≤ 35 years revealed that 35% of young mothers had C677T mutation (10% had homozygous mutation and 25% had heterozygous mutation). MTHFR C677T polymorphism was found to be a possible maternal genetic risk factor for DS although statistically non-significant.Other maternal risk factors included the use of oral contraceptive pills (OCP) 6 months before pregnancy which was significantly higher only in DSmothers ≥ 35 years. on the other hand, parental consanguinity, maternal grandparents’ ages, the presence of genital infection and birth order did not show a significant difference between young and old mothers of DS.Conclusion: MTHFR C677T could not be considered as a maternal risk factor in young Egyptian mothers of DS. The risk effect may depend on gene-environment interaction between the genotype and dietary intake in particular folic acid consumption which should be further studied on a larger scale population including other MTHFR polymorphisms and environmental factors. Other risk factors may include the use of OCP in older mothers. Parents consanguinity, paternal age and maternal grandparents’ ages were not found to be risk factors in DS in this study.Keywords: Down syndrome, risk factors, mothers, MTHFR
Low Viral Load Does Not Exclude Significant Liver Damage in Patients with Chronic HBV Infection in Bangladesh
Background: In general, it is assumed that patients with chronic hepatitis B virus (HBV) infection with high viral load exhibit increased liver damages. Accordingly, the treatment guidelines emphasize on reducing viral load in chronic HBV carriers. The ethical and scientific basis of these observations was mainly accumulated from investigations from developed countries of the world. More than 80% chronic HBV carriers live in the developing nations of the world, but little is known about relationship between HBV viral load and extent of liver damages in these countries. In this study, we addressed this issue to provide insights about this. Methods: In this retrospective study we reviewed the records of 210 chronic hepatitis B (CHB) patients from our pool of 561 Bangladeshi CHB patients. All of these 210 patients had low HBV DNA (<105 copies/ml by PCR). Of them 16 were HBeAg +ve and rest 194 HBeAg -ve. They have also been tested for other serologic markers of HBV (i.e. HBsAg, anti-HBe), HCV (i.e. anti-HCV) and serum alaninetransaminase (ALT) level. All patients also underwent per-cutaneous liver biopsy. Results: 37.5% (6/16) HBeAg +ve patients with low HBV DNA had significant hepatic necro-inflammation (HAI-NI ≥7), whereas this figure was 31.44% (61/194) in case of HBeAg -ve patients. On the other hand significant hepatic fibrosis (HAI-F ≥3) was observed in 31.25% (5/16) and 14.4% (28/194) in HBeAg +ve and -ve patients respectively. Conclusion: This study shows that a correlation could not be established between viral load and liver damage in patients with CHB in Bangladesh. A significant percentage of patients with low HBV DNA may have marked hepatic necro-inflammation and fibrosis, more so in case of HBeAg +ve CHB. Further study may be needed to find out the influence of other factors on liver damages in CHB patients in developing nations like Bangladesh, where about 8 million chronic HBV carriers are living. Most of these patients have not been characterized and treatment modalities have not been defined for them. Our study may suggest the research direction for management of these cases. Key Words: Low HBV DNA; Chronic hepatitis B; Hepatic necro-inflammation; Hepatic fibrosis.DOI: 10.3329/bsmmuj.v1i1.3693 BSMMU J 2008; 1(1): 19-2
Extensive psoriasis induced by pegylated interferon: a case report
This paper describes the clinical course of a patient with chronic hepatitis C, genotype 2a/2c, previously treated with Interferon α2b and subsequently with Lymphoblastoid Interferon without any response, and also without any cutaneous side effects. The patient, a 50 year-old woman, was re-treated with Pegylated α2b Interferon plus Ribavirin for 24 weeks, at standard doses; during the third month of therapy she developed a mild form of psoriasis. However, encouraged by the progressive improvement of her transaminase levels and viral load decrease, the patient asked to continue the treatment; she normalized the transaminase levels during the fourth month and showed HCV-RNA negativity during the fifth month of therapy. Nevertheless, the psoriasis become worse, extending to over 75% of her body. Therapy was completed after sixth months. A month after the therapy was ceased, the patient's psoriasis receded spontaneously and completely. During the subsequent four years the patient did not experience any recurrence of either the hepatic disease or the psoriasis
Fracture properties investigation of Artocarpus Odoratissimus composite with Polypropylene (PP)
Wood plastic composites (WPC) were done using a matrix of polypropylene (PP) thermoplastic resin with wood fibre from Artocarpus odoratissimus as filler. The purpose of this study is to investigate the fracture properties of Artocarpus odoratissimus composite with PP. The WPC was manufactured by a hot - press technique with varying formulations which are 10:0 (100% pure PP), 50:50 (40 g of wood fiber and 40 g of PP) and 60:40 (48 g of wood fiber and 32 g of PP). The mechanical properties were investigated. Tensile and flexural were carried out according to ASTM D 638 and ASTM D 790. The results were analysed to calculate the tensile strength. Tensile strength at break is ranged from 13.2 N/mm2 to 21.7 N/mm2 . While, the flexural strength obtained is varying from 14.7 N/mm2 to 31.1 N/mm2 . The results of the experiment showed that tensile and flexural properties of the composite increased with the adding of wood fiber material. Finally, the Scanning Electron Microscope (SEM), have been done to study the fracture behaviour of the WPC specimens
Contamination of Fresh Produce with Antibiotic-Resistant Bacteria and Associated Risks to Human Health: A Scoping Review.
Fresh produce, when consumed raw, can be a source of exposure to antimicrobial residues, antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) of clinical importance. This review aims to determine: (1) the presence and abundance of antimicrobial residues, ARB and ARGs in fresh agricultural products sold in retail markets and consumed raw; (2) associated health risks in humans; and (3) pathways through which fresh produce becomes contaminated with ARB/ARGs. We searched the Ovid Medline, Web of Science and Hinari databases as well as grey literature, and identified 40 articles for inclusion. All studies investigated the occurrence of multidrug-resistant bacteria, and ten studies focused on ARGs in fresh produce, while none investigated antimicrobial residues. The most commonly observed ARB were E. coli (42.5%) followed by Klebsiella spp. (22.5%), and Salmonella spp. (20%), mainly detected on lettuce. Twenty-five articles mentioned health risks from consuming fresh produce but none quantified the risk. About half of the articles stated produce contamination occurred during pre- and post-harvest processes. Our review indicates that good agricultural and manufacturing practices, behavioural change communication and awareness-raising programs are required for all stakeholders along the food production and consumption supply chain to prevent ARB/ARG exposure through produce
Transient peak-strain matching partially recovers the age-impaired mechanoadaptive cortical bone response
Mechanoadaptation maintains bone mass and architecture; its failure underlies age-related decline in bone strength. It is unclear whether this is due to failure of osteocytes to sense strain, osteoblasts to form bone or insufficient mechanical stimulus. Mechanoadaptation can be restored to aged bone by surgical neurectomy, suggesting that changes in loading history can rescue mechanoadaptation. We use non-biased, whole-bone tibial analyses, along with characterisation of surface strains and ensuing mechanoadaptive responses in mice at a range of ages, to explore whether sufficient load magnitude can activate mechanoadaptation in aged bone. We find that younger mice adapt when imposed strains are lower than in mature and aged bone. Intriguingly, imposition of short-term, high magnitude loading effectively primes cortical but not trabecular bone of aged mice to respond. This response was regionally-matched to highest strains measured by digital image correlation and to osteocytic mechanoactivation. These data indicate that aged bone’s loading response can be partially recovered, non-invasively by transient, focal high strain regions. Our results indicate that old murine bone does respond to load when the loading is of sufficient magnitude, and bones’ age-related adaptation failure may be due to insufficient mechanical stimulus to trigger mechanoadaptation
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