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

In vitro response from cotyledon and hypocotyls explants in tomato by inducing 6-benzylaminopurine

Differential response of tomato was evaluated by hypocotyls and cotyledon explants on 6- benzylaminopurine (BAP) containing MS media. Among the four levels (0, 1, 2 and 4 mg/l) of BAP employed in Murashige and Skoog (MS) media, 2.0 mg/l BAP was found superior in growth traits (number of shoots/explants and shoot length) and cultivars. No significant difference was noticed between cotyledon and hypocotyls explants on media having 2.0 mg/l BAP. In the same treatment, shoot length was significantly different between cotyledon and hypocotyls derived explants. No adventitious shoots was noted in the control and higher concentration of BAP containing media but theexplants turned into callus on media having 4.0 mg/l BAP

Fecal occult blood and fecal calprotectin as point-of-care markers of intestinal morbidity in Ugandan children with Schistosoma mansoni infection.

BACKGROUND: Calprotectin is a calcium-binding cytoplasmic protein found in neutrophils and increasingly used as a marker of bowel inflammation. Fecal occult blood (FOB) is also a dependable indicator of bowel morbidity. The objective of our study was to determine the applicability of these tests as surrogate markers of Schistosoma mansoni intestinal morbidity before and after treatment with praziquantel (PZQ). METHODS: 216 children (ages 3-9 years old) from Buliisa District in Lake Albert, Uganda were examined and treated with PZQ at baseline in October 2012 with 211 of them re-examined 24 days later for S. mansoni and other soil transmitted helminths (STH). POC calprotectin and FOB assays were performed at both time points on a subset of children. Associations between the test results and infection were analysed by logistic regression. RESULTS: Fecal calprotectin concentrations of 150-300 µg/g were associated with S. mansoni egg patent infection both at baseline and follow up (OR: 12.5 P = 0.05; OR: 6.8 P = 0.02). FOB had a very strong association with baseline anemia (OR: 9.2 P = 0.03) and medium and high egg intensity schistosomiasis at follow up (OR: 6.6 P = 0.03; OR: 51.3 P = 0.003). Both tests were strongly associated with heavy intensity S. mansoni infections. There was a significant decrease in FOB and calprotectin test positivity after PZQ treatment in those children who had egg patent schistosomiasis at baseline. CONCLUSIONS: Both FOB and calprotectin rapid assays were found to correlate positively and strongly with egg patent S. mansoni infection with a positive ameloriation response after PZQ treatment indicative of short term reversion of morbidity. Both tests were appropriate for use in the field with excellent operational performance and reliability. Due to its lower-cost which makes its scale-up of use affordable, FOB could be immediately adopted as a monitoring tool for PC campaigns for efficacy evaluation before and after treatment

Revising the WHO verbal autopsy instrument to facilitate routine cause-of-death monitoring.

OBJECTIVE: Verbal autopsy (VA) is a systematic approach for determining causes of death (CoD) in populations without routine medical certification. It has mainly been used in research contexts and involved relatively lengthy interviews. Our objective here is to describe the process used to shorten, simplify, and standardise the VA process to make it feasible for application on a larger scale such as in routine civil registration and vital statistics (CRVS) systems. METHODS: A literature review of existing VA instruments was undertaken. The World Health Organization (WHO) then facilitated an international consultation process to review experiences with existing VA instruments, including those from WHO, the Demographic Evaluation of Populations and their Health in Developing Countries (INDEPTH) Network, InterVA, and the Population Health Metrics Research Consortium (PHMRC). In an expert meeting, consideration was given to formulating a workable VA CoD list [with mapping to the International Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) CoD] and to the viability and utility of existing VA interview questions, with a view to undertaking systematic simplification. FINDINGS: A revised VA CoD list was compiled enabling mapping of all ICD-10 CoD onto 62 VA cause categories, chosen on the grounds of public health significance as well as potential for ascertainment from VA. A set of 221 indicators for inclusion in the revised VA instrument was developed on the basis of accumulated experience, with appropriate skip patterns for various population sub-groups. The duration of a VA interview was reduced by about 40% with this new approach. CONCLUSIONS: The revised VA instrument resulting from this consultation process is presented here as a means of making it available for widespread use and evaluation. It is envisaged that this will be used in conjunction with automated models for assigning CoD from VA data, rather than involving physicians

NLRP6 negatively regulates innate immunity and host defence against bacterial pathogens

Members of the intracellular nucleotide-binding and oligomerization domain (NOD)-like receptor (NLR) family contribute to immune responses through activation of nuclear factor-kappa B (NF-kappa B), type I interferon and inflammasome signalling(1). Mice lacking the NLR family member NLRP6 were recently shown to be susceptible to colitis and colorectal tumorigenesis(2-4), but the role of NLRP6 in microbial infections and the nature of the inflammatory signalling pathways regulated by NLRP6 remain unclear. Here we show that Nlrp6-deficient mice are highly resistant to infection with the bacterial pathogens Listeria monocytogenes, Salmonella typhimurium and Escherichia coli. Infected Nlrp6-deficient mice had increased numbers of monocytes and neutrophils in circulation, and NLRP6 signalling in both haematopoietic and radioresistant cells contributed to increased susceptibility. Nlrp6 deficiency enhanced activation of mitogen-activated protein kinase (MAPK) and the canonical NF-kappa B pathway after Toll-like receptor ligation, but not cytosolic NOD1/2 ligation, in vitro. Consequently, infected Nlrp6-deficient cells produced increased levels of NF-kappa B-and MAPK-dependent cytokines and chemokines. Thus, our results reveal NLRP6 as a negative regulator of inflammatory signalling, and demonstrate a role for this NLR in impeding clearance of both Gram-positive and -negative bacterial pathogens

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Structural, electronic and optical studies of Sr<inf>2</inf>NiTeO<inf>6</inf> double perovskite by first-principle DFT–LDA + U calculation

The structural, electronic and optical properties of monoclinic Sr2NiTeO6 double perovskite have been studied using corrected density functional theory–local density approximation with applying of Hubbard U corrected energy (DFT–LDA + U) method in plane-wave pseudopotential basis. The influence of on-site Coulomb interaction on structural, electronic and optical properties of Sr2NiTeO6 double perovskite compound, which consists of strongly localized Ni 3d electrons, were investigated. The highly Coulomb repulsion between electrons was corrected using Hubbard U parameter, varying from 0 to 8 eV for Ni 3d orbitals. The calculated results demonstrated that Sr2NiTeO6 double perovskite was sensitive to the change in U values. The optimized structural properties give a good agreement with experiment and other calculation data with lattice parameters a = 5.673 Å, b = 5.565 Å, c = 7.847 Å, α = 89.999°, β = 90.257° and γ = 90.000°. The DFT–LDA + U predicted the calculated electronic band structure of Sr2NiTeO6 was showed metallic behaviour (0 and 2 eV) and insulator behaviour (4, 6 and 8 eV). The density of state (DOS) shows that there was a significant effect on hybridization of Ni 3d and O 2p states at the conduction and valence band, respectively. Moreover, the results of optical studies such as dielectric function, absorption and reflectivity were found significant to the variation of U values applied indicates that the U values give a better description on the electronic localization of Ni 3d states

BACTEC MGIT 960 TM system for screening of Mycobacterium tuberculosis complex among cattle

Bovine tuberculosis remains a disease of economic and public health importance in developing countries. The largest number of new cases of tuberculosis usually occurs in South-East Asia region and Africa. This study was aimed to evaluate the recent technique (BACTEC MGIT 960 TM system) for screening of Mycobacterium tuberculosis complex among cattle in Egypt. From the 1180 cattle examined in three different Governorates (El-Sharkia, El-Gharbia and El-Monefeia) by single intradermal tuberculin test, 29 animals (2.46%) were positive reactors. The post mortem examination of the positive reactors showed that 22 animals (75.9%) had visible lesions [respiratory form (31.0%), digestive form (13.8%), mixed form (20.7%) and generalized form (10.3%)], while seven (24.1%) did not show visible lesions. The results of isolation and identification using conventional culture method (Lowenstein- Jensen medium) were 22 mycobacterial isolates (75.9%), 20 (68.97%) Mycobacterium bovis and 2 (6.9%) unidentified slow growth. The BACTEC MGIT 960 TM system was used for recovery of Mycobacteria and compared with conventional culture method (Lowenstein-Jensen medium). The recovery rate of BACTEC MGIT 960 TM system was 82.8%, while that of Lowenstein-Jensen medium was 75.9%. The mean time for detection of Mycobacteria was 17.8 ± 0.9 days and 46.5 ± 0.4 days for BACTEC MGIT 960 TM system and Lowenstein-Jensen medium, respectively while the contamination rate with BACTEC MGIT 960 TM system was 6.9% and 10.3% in Lowenstein-Jensen medium.Key words: Bovine tuberculosis, tuberculin test, Lowenstein-Jensen medium, BACTEC system

Multiplex polymerase chain reaction for detection and characterization of shiga toxigenic Escherichia coli (STEC)

Escherichia coli is ubiquitous in the cow's environment that is contaminated by feces, and it is also a frequent cause of bovine mastitis. Thus, the present study was targeted at the rapid detection and characterization of shiga toxigenic E. coli (STEC) in bovine fecal and milk samples. Twenty two strains of E. coli (39.29%) were isolated from 56 diarrheic calves, while only 5 strains (20.83%) were isolated from apparently normal contact calves. Moreover, 20 strains of E. coli (25%) were isolated from milk samples collected from 80 animals suffering from mastitis and subclinical mastitis. E. coli serovars yielded from bacteriological examination of milk samples were similar to that of fecal samples. Serogroup-specific multiplex polymerase chain reaction (PCR) assay could detect all the bacteriologically positive samples as well as 4 strains (7.98%), O157:H7 and 3 strains (5.36%), O111 from diarrheic calves and 2 strains (8.33%), O111 from normal calves. Such samples were proved to be negative by bacteriological examination. Multiplex PCR for detection of genes encoding accessorySTEC virulence factors, such as shiga toxin type-2 (stx2) and intimin gene (eaeA) revealed the specificity of such gene to O157:H7 serovars and small number of other sero-groups