Barrier inhomogeneities of Al/p-In2Te3 thin film Schottky diodes

The current-voltage (I-V) and capacitance-voltage (C-V) characteristics of p-In2Te3/Al thin films Schottky diodes papered by Flash Evaporation technique were measured in the temperature range 303-335 K have been interpreted on the basis of the assumption of a Gaussian distribution of barrier heights (φbo) due to barrier height inhomogeneities that prevail at the interface. It has been found that the occurrence of Gaussian distribution of BHs is responsible for the decrease of the apparent BH (φbo) and increase of the ideality factor (η). The inhomogeneities are considered to have a Gaussian distribution with a mean barrier height of (φbm) and standard deviation (σs) at zero-bias. Furthermore, the activation energy value (φb) at T = 0 and Richardson constant (A**) value was obtained as 0.587 eV and 3.09 Acm– 2 K– 1 by means of usual Richardson plots. Hence, it has been concluded that the temperature dependence of the I-V characteristics of p-In2Te3/Al Schottky Diodes can be successfully explained on the basis of TE mechanism with a Gaussian distribution of the BHs. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2790

Marine bacterial, archaeal and protistan association networks reveal ecological linkages

Microbes have central roles in ocean food webs and global biogeochemical processes, yet specific ecological relationships among these taxa are largely unknown. This is in part due to the dilute, microscopic nature of the planktonic microbial community, which prevents direct observation of their interactions. Here, we use a holistic (that is, microbial system-wide) approach to investigate time-dependent variations among taxa from all three domains of life in a marine microbial community. We investigated the community composition of bacteria, archaea and protists through cultivation-independent methods, along with total bacterial and viral abundance, and physico-chemical observations. Samples and observations were collected monthly over 3 years at a well-described ocean time-series site of southern California. To find associations among these organisms, we calculated time-dependent rank correlations (that is, local similarity correlations) among relative abundances of bacteria, archaea, protists, total abundance of bacteria and viruses and physico-chemical parameters. We used a network generated from these statistical correlations to visualize and identify time-dependent associations among ecologically important taxa, for example, the SAR11 cluster, stramenopiles, alveolates, cyanobacteria and ammonia-oxidizing archaea. Negative correlations, perhaps suggesting competition or predation, were also common. The analysis revealed a progression of microbial communities through time, and also a group of unknown eukaryotes that were highly correlated with dinoflagellates, indicating possible symbioses or parasitism. Possible ‘keystone’ species were evident. The network has statistical features similar to previously described ecological networks, and in network parlance has non-random, small world properties (that is, highly interconnected nodes). This approach provides new insights into the natural history of microbes

A review on food allergy: pathogenesis, diagnosis methods and treatment approaches

An exaggerated immune reaction to a food that takes place in a vulnerable host is referred to as a food allergy. The two main types of food-induced allergy diseases are those caused by Immunoglobulin E (IgE) antibodies and those caused by non-IgE-mediated mechanisms. These reactions are frequently brought on by food allergens such as egg, seafood, fruits, milk, soy, peanut, etc. In India, roughly 26.5% of the population has been impacted by food-induced allergy diseases. Age, sex, heredity, and geographic location of the patient, as well as vitamin D deficiency and other allergic reactions, are risk factors that might result in life-threatening food allergies. Skin prick test, oral food challenge, component resolved diagnostic testing are the most widely used diagnostic tests for food allergy. Pharmacotherapy of food induced allergic reactions include epinephrine therapy and use of antihistamine drugs. However, the main stay of treatment is avoidance of responsible food and food desensitization. Some home remedies can also be used in order to control allergic reactions caused by food allergens. All these remedies directly or indirectly improve the health of immune system to prevent food induced allergic reactions. The objective of this study was to throw a light on the pathogenesis, diagnostic methods and possible treatment options for food allergy

Gastric Outlet Obstruction at Bugando Medical Centre in Northwestern Tanzania: A Prospective Review of 184 Cases.

Gastric outlet obstruction poses diagnostic and therapeutic challenges to general surgeons practicing in resource-limited countries. There is a paucity of published data on this subject in our setting. This study was undertaken to highlight the etiological spectrum and treatment outcome of gastric outlet obstruction in our setting and to identify prognostic factors for morbidity and mortality. This was a descriptive prospective study which was conducted at Bugando Medical Centre between March 2009 and February 2013. All patients with a clinical diagnosis of gastric outlet obstruction were, after informed consent for the study, consecutively enrolled into the study. Statistical data analysis was done using SPSS computer software version 17.0. A total of 184 patients were studied. More than two-third of patients were males. Patients with malignant gastric outlet obstruction were older than those of benign type. This difference was statistically significant (p < 0.001). Gastric cancer was the commonest malignant cause of gastric outlet obstruction where as peptic ulcer disease was the commonest benign cause. In children, the commonest cause of gastric outlet obstruction was congenital pyloric stenosis (13.0%). Non-bilious vomiting (100%) and weight loss (93.5%) were the most frequent symptoms. Eighteen (9.8%) patients were HIV positive with the median CD 4+ count of 282 cells/μl. A total of 168 (91.3%) patients underwent surgery. Of these, gastro-jejunostomy (61.9%) was the most common surgical procedure performed. The complication rate was 32.1 % mainly surgical site infections (38.2%). The median hospital stay and mortality rate were 14 days and 18.5% respectively. The presence of postoperative complication was the main predictor of hospital stay (p = 0.002), whereas the age > 60 years, co-existing medical illness, malignant cause, HIV positivity, low CD 4 count (<200 cells/μl), high ASA class and presence of surgical site infection significantly predicted mortality ( p< 0.001). The follow up of patients was generally poor as more than 60% of patients were lost to follow up. Gastric outlet obstruction in our setting is more prevalent in males and the cause is mostly malignant. The majority of patients present late with poor general condition. Early recognition of the diagnosis, aggressive resuscitation and early institution of surgical management is of paramount importance if morbidity and mortality associated with gastric outlet obstruction are to be avoided

A New Six Point Finite Difference Scheme for Nonlinear Waves Interaction Model

In the paper, the coupled 1D Klein-Gordon-Zakharov system (KGZ-equations in short) is considered as the model equation for wave-wave interaction in ionic media. A finite difference scheme is derived for the model equations. A new six point scheme, which is equivalent to the multi-symplectic integrator, is derived. The numerical simulation is also presented for the model equations. Keywords: Coupled 1D Klein-Gordon-Zakharov system; Energy conservation; Six-point schem

Dark matter spikes around Sgr A∗ in γ-rays

We use H.E.S.S. γ-ray observations of Sgr A∗ to derive novel limits on the Dark Matter (DM) annihilation cross-section. We quantify their dependence on uncertainties i) in the DM halo profile, which we vary from peaked to cored, and ii) in the shape of the DM spike around Sgr A∗, dynamically heated by the nuclear star cluster. For peaked halo profiles and depending on the heating of the spike, our limits are the strongest existing ones for DM masses above a few TeV. Our study contributes to assessing the influence of the advancements in our knowledge of the Milky Way on determining the properties of DM particles

Identification of a hypoxia-regulated miRNA signature in bladder cancer and a role for miR-145 in hypoxia-dependent apoptosis

Background: Hypoxia leads to the stabilisation of the hypoxia-inducible factor (HIF) transcription factor that drives the expression of target genes including microRNAs (miRNAs). MicroRNAs are known to regulate many genes involved in tumourigenesis. The aim of this study was to identify hypoxia-regulated miRNAs (HRMs) in bladder cancer and investigate their functional significance. Methods: Bladder cancer cell lines were exposed to normoxic and hypoxic conditions and interrogated for the expression of 384 miRNAs by qPCR. Functional studies were carried out using siRNA-mediated gene knockdown and chromatin immunoprecipitations. Apoptosis was quantified by annexin V staining and flow cytometry. Results: The HRM signature for NMI bladder cancer lines includes miR-210, miR-193b, miR-145, miR-125-3p, miR-708 and miR-517a. The most hypoxia-upregulated miRNA was miR-145. The miR-145 was a direct target of HIF-1a and two hypoxia response elements were identified within the promoter region of the gene. Finally, the hypoxic upregulation of miR-145 contributed to increased apoptosis in RT4 cells. Conclusions: We have demonstrated the hypoxic regulation of a number of miRNAs in bladder cancer. We have shown that miR- 145 is a novel, robust and direct HIF target gene that in turn leads to increased cell death in NMI bladder cancer cell lines

The role of immunohistochemistry in medullomyoblastoma – a case series highlighting divergent differentiation

<p>Abstract</p> <p>Aims</p> <p>To analyse the histo-morphology of cases of medullomyoblastoma and identifying its divergent differentiation.</p> <p>Methods</p> <p>A retrospective review of all cases reported as medulloblastoma between the period of Jan 2000 to Dec 2006 was carried out on Hematoxylin and eosin (H & E) stained slides. The cases were screened on light microscopy for primitive neuroectodermal component of a medulloblastoma accompanied by areas of "myoid" differentiation, identified on the basis of presence of strap cells (indicating a clear skeletal muscle differentiation) and/or large anaplastic cells with vescicular nuclei and moderate to abundant amount of eosinophilic cytoplasm. All these cases were subjected to a panel of immunohistochemical stains, including Desmin, GFAP, NFP, HMB45, SMA, S100, CK and EMA. Ultrastructral analysis was done on tissue obtained from paraffin blocks in 2 cases.</p> <p>Results</p> <p>Male predominance (M:F = 5:1) was noted with an incidence of five percent of all cases of medulloblastoma (6 out of 120 cases) over a period of 6 years. Primitive neuroectodermal areas were accompanied with areas of "myoid" differentiation, 5 cases showing strap cells. Two cases with epithelial and cartilaginous differentiation were seen. Three cases showed focal melanocytic differentiation, identified only on HMB45 immunostaining. Four cases showed glial differentiation. Neuronal differentiation again was very focally seen in two cases, of which one was identified only by NFP immunostain. Seventh case is included in the study, however it is not considered to calculate incidence as it occurred beyond the period of 6 years of records search.</p> <p>Conclusion</p> <p>Medullomyoblastoma is a rare childhood tumor of cerebellum. Majority of cases reveal divergent differentiation, which are identified with the help of panel of immunostains indicating multi-potential nature of primitive neuroectodermal cells.</p

Site-selective protein-modification chemistry for basic biology and drug development.

Nature has produced intricate machinery to covalently diversify the structure of proteins after their synthesis in the ribosome. In an attempt to mimic nature, chemists have developed a large set of reactions that enable post-expression modification of proteins at pre-determined sites. These reactions are now used to selectively install particular modifications on proteins for many biological and therapeutic applications. For example, they provide an opportunity to install post-translational modifications on proteins to determine their exact biological roles. Labelling of proteins in live cells with fluorescent dyes allows protein uptake and intracellular trafficking to be tracked and also enables physiological parameters to be measured optically. Through the conjugation of potent cytotoxicants to antibodies, novel anti-cancer drugs with improved efficacy and reduced side effects may be obtained. In this Perspective, we highlight the most exciting current and future applications of chemical site-selective protein modification and consider which hurdles still need to be overcome for more widespread use.We thank FCT Portugal (FCT Investigator to G.J.L.B.), the EU (Marie-Curie CIG to G.J.L.B. and Marie-Curie IEF to O.B.) and the EPSRC for funding. G.J.L.B. is a Royal Society University Research Fellow.This is the author accepted manuscript. The final version is available from NPG via http://dx.doi.org/10.1038/nchem.239