High Performance Molybdenum Disulfide Amorphous Silicon Heterojunction Photodetector

One important use of layered semiconductors such as molybdenum disulfide (MoS2) could be in making novel heterojunction devices leading to functionalities unachievable using conventional semiconductors. Here we demonstrate an ultrafast metal-semiconductor-metal heterojunction photodetector, made of MoS2 and amorphous silicon (a-Si), with rise and fall times of about 0.3 ms. This is more than an order of magnitude improvement over response times of conventional a-Si (~5 ms) and best reported MoS2 devices (~50 ms). The van-der-waals heterojunction presented here yields a high photoresponsivity of 210 mA/W at green light-the wavelength used in commercial imaging systems. This responsivity is 4X larger than that of the best MoS2 devices, and 2X larger than that of commercial a-Si devices. The 10X improvement in speed with high photoresponsivity provides a potential solution to a decades-long problem for thin film imagers and could find applications in large area electronics such as biomedical imaging and x-ray fluoroscopy

How Should Governments Address High Levels of Natural Radiation and Radon--Lessons from the Chernobyl Nuclear Accident and Ramsar, Iran

The authors discuss the high levels of natural background radiation in Ramsar, Iran, and offer data indicating that this has had little effect on the health of Ramsar\u27s inhabitants. The authors then examine the implications their research could have for public health policy

Histochemical study of the oesophagus in the chukar partridge (Alectoris chukar) embryo

Study of the histogenesis of different organs is a useful laboratory method which helps us achieve accurate basic information about organ development during the embryonic period. It also reveals histological differences of each organ in different species. This research was carried out to study the histogenesis of the oesophagus of chukar partridge. For this purpose, the embryonated eggs were placed in the incubator and the embryos were collected between the 5th to 24th days of incubation period. The specimens were fixed in Bouin’s solution, and routine histotechnique processes were performed. The slides were finally stained with haematoxylin-eosin, Periodic Acid Schiff, Alcian Blue and Masson Trichrome, and the developmental changes of the oesophagus during the embryonic period were studied by light microscope. The four layers of oesophagus, including, the mucosa, submucosa, tunica muscularis and advantitia/serosa, both in cervical and thoracic oesophagus, were studied. During days 5 to 24 of incubation, developmental events in the oesophagus such as changes in the oesophageal epithelium, formation of muscularis mucosae and tunica muscularis, development of the mucous glands and the type of their secretion, were observed. Finally the results were compared with those of other studied avian species and the similarities and differences were discussed

Modelling the Effects of Competing Anions on Fluoride Removal by Functionalized Polyacrylonitrile Coated with Iron Oxide Nanoparticles

Fe2O3 nano particles supported on functionalized poly-acrylonitrile was prepared. PAN-oxime-nano Fe2O3 was characterized by XRD, FTIR andTEMand used for fluoride adsorption. The adsorption capacity increased with increasing initial fluoride concentration and reaction time. Fluoride-removal performance of PAN-oxime-nano Fe2O3 was also tested in the presence of various competing anions usually found in drinking water. Competitive sorption between fluoride and competing anions showed a minimum preference for chloride counterions. Carbonate was the greatest competitor for fluoride removal followed by phosphate and sulphate. Counterion presence decreased fluoride adsorption capacity in order of CO32−> PO43−> SO42−> Cl−. The presence of anions at various concentrations decreased fluoride adsorption capacity on PAN-oxime-nano Fe2O3 by 1.22 to 6.51 mg g–1. Effects of each two anions exist simultaneously in aqueous solution on fluoride adsorption was investigated using Tukey’s test (called also a pairwise comparison). Tukey’s HSD results indicate that the differences between various pairs of anions are significant (P < 0.05), except for chloride–sulphate (P = 0.08). In the design of PAN-oxime-nano Fe2O3 for environmental applications, the strong influence of the counter ions must be considered.KEYWORDS Fluoride, PAN-oxime- nano Fe2O3, counterion, adsorption

Biological Activities of Essential Oils: From Plant Chemoecology to Traditional Healing Systems

Essential oils are complex mixtures of hydrocarbons and their oxygenated derivatives arising from two different isoprenoid pathways. Essential oils are produced by glandular trichomes and other secretory structures, specialized secretory tissues mainly diffused onto the surface of plant organs, particularly flowers and leaves, thus exerting a pivotal ecological role in plant. In addition, essential oils have been used, since ancient times, in many different traditional healing systems all over the world, because of their biological activities. Many preclinical studies have documented antimicrobial, antioxidant, anti-inflammatory and anticancer activities of essential oils in a number of cell and animal models, also elucidating their mechanism of action and pharmacological targets, though the paucity of in human studies limits the potential of essential oils as effective and safe phytotherapeutic agents. More well-designed clinical trials are needed in order to ascertain the real efficacy and safety of these plant products

MicroRNA-129-1 acts as tumour suppressor and induces cell cycle arrest of GBM cancer cells through targeting IGF2BP3 and MAPK1

Background MicroRNA-129-1 (miR-129-1) seems to behave as a tumour suppressor since its decreased expression is associated with different tumours such as glioblastoma multiforme (GBM). GBM is the most common form of brain tumours originating from glial cells. The impact of miR-129-1 downregulation on GBM pathogenesis has yet to be elucidated. Methods MiR-129-1 was overexpressed in GBM cells, and its effect on proliferation was investigated by cell cycle assay. MiR-129-1 predicted targets (CDK6, IGF1, HDAC2, IGF2BP3 and MAPK1) were also evaluated by western blot and luciferase assay. Results Restoration of miR-129-1 reduced cell proliferation and induced G1 accumulation, significantly. Several functional assays confirmed IGF2BP3, MAPK1 and CDK6 as targets of miR-129-1. Despite the fact that IGF1 expression can be suppressed by miR-129-1, through 30-untranslated region complementary sequence, we could not find any association between IGF1 expression and GBM. MiR-129-1 expression inversely correlates with CDK6, IGF2BP3 and MAPK1 in primary clinical samples. Conclusion This is the first study to propose miR129-1 as a negative regulator of IGF2BP3 and MAPK1 and also a cell cycle arrest inducer in GBM cells. Our data suggests miR-129-1 as a potential tumour suppressor and presents a rationale for the use of miR-129-1 as a novel strategy to improve treatment response in GBM

Evaluating the affected the factors of research in Ilam university of Medical Sciences during 2006-2011

Research is one of the most important parameter in developing of each country, for this .... Universities are of most importance. The faculty members are more interested in education rather than research due to different factors. The current study aimed to evaluate such factors among the faculty members of Ilam university of Medical Sciences during 2006 until 2011. This is a retrospective cross-sectional study based on data collected by a questionnaire and interview. Data analyzed using descriptive statistics by SPSS package 18. Totally a research projects from researchers was enrolled in this study of which 74.6 men and 93.4 were married. 59.6 of researchers has BSc (51.1), MSc and PhD (31.9) and 16.6 worked of educational Deputy of this university. Accessing to scientific data banks, and lack of English language skills were among the most effective factors n research and satisfaction of researchers while good communication with staff of university research Department was in high importance