Gas-Phase Synthesis for Label-Free Biosensors: Zinc-Oxide Nanowires Functionalized with Gold Nanoparticles

Metal oxide semiconductor nanowires have important applications in label-free biosensing due to their ease of fabrication and ultralow detection limits. Typically, chemical functionalization of the oxide surface is necessary for specific biological analyte detection. We instead demonstrate the use of gas-phase synthesis of gold nanoparticles (Au NPs) to decorate zinc oxide nanowire (ZnO NW) devices for biosensing applications. Uniform ZnO NW devices were fabricated using a vapor-solid-liquid method in a chemical vapor deposition (CVD) furnace. Magnetron-sputtering of a Au target combined with a quadrupole mass filter for cluster size selection was used to deposit Au NPs on the ZnO NWs. Without additional functionalization, we electrically detect DNA binding on the nanowire at sub-nanomolar concentrations and visualize individual DNA strands using atomic force microscopy (AFM). By attaching a DNA aptamer for streptavidin to the biosensor, we detect both streptavidin and the complementary DNA strand at sub-nanomolar concentrations. Au NP decoration also enables sub-nanomolar DNA detection in passivated ZnO NWs that are resilient to dissolution in aqueous solutions. This novel method of biosensor functionalization can be applied to many semiconductor materials for highly sensitive and label-free detection of a wide range of biomolecules

PROVABLE MULTI-COPY DYNAMIC DATA POSSESSION WITH MULTI-OWNER IN CLOUD COMPUTING SYSTEM

Most of organization store almost unlimited amount of their data in cloud with facility of retrieving. Users pay fees for storing data. Many of the users are in collaborative relationship; at that time data sharing and dynamic operation are useful to improve productive benefits. So, propose system introduced the multi owner with data sharing concept. Most of the time customers store their important data on multiple servers for accessing on different geographical location. When data store on multiple server then data owner need evidence of all outsourced file copies are intact. But some time few copies may be corrupt. So, proposed system identifies corrupted copies and corrects it before dynamic operation performs. In addition, proposed system allows multi-owner facility for sharing data

Osteomyelitis affecting mandible in tuberculosis patients

Abstract Tuberculosis (TB) is a frequent health problem in developing nations. It has two forms pulmonary and secondary causing other kinds of TB, collectively denoted extra pulmonary tuberculosis. The prevalence of extra pulmonary TB has increased in the last couple of years. Maxillofacial manifestations of tuberculosis form nearly 10% of all extra pulmonary manifestations of the disease. Extra pulmonary TB involving maxillofacial region is our prime concern. Very few cases of TB of the temporomandibular joint (TMJ) and mandible have been reported in literature. The clinical appearance of TB infection of the TMJ has been described as unspecific, resembling arthritis, osteomyelitis, cancer or any kind of chronic joint diseases. This article describes two cases where the bone, namely TMJ and angle of mandible are affected by tuberculosis. In addition to conventional radiographs we used Cone Beam Computed tomography (CBCT) to explore the third dimension of the lesion

Effect of methomyl on hepatic mixed function oxidases in rats

Objective: To study the effect of the methomyl on mixed function oxidase system in rats. Materials and Methods: The effect of the methomyl on mixed function oxidase was studied using different dosages, durations and sex. Microsomes were isolated using the calcium precipitation method. The levels of cytochrome P 450 , and cytochrome b 5 were determined using extinction coefficient of 91 and 85 mM -1 respectively. The activities of drug metabolizing enzymes, hemoglobin content, liver function enzymes, and serum cholinesterase activity were assayed by using standard methods. Results: Intraperitoneal administration of methomyl (4 mg/kg body weight) showed significant decrease in the level of cytochrome P 450 , and the activities of aminopyrine N-demethylase and aniline hydroxylase on the third day of the treatment. Methomyl (4 mg/kg) treatment of old male rat and adult female rat also showed a decrease in the level of cytochrome P 450 , and aminopyrine N-demethylase activity. The serum samples from methomyl treated rats (male and female), when analyzed for alanine aminotransferase (SGPT) and aspartate aminotransferase (SGOT) as markers of the liver toxicity, showed significant increase in the activity. The activities of SGPT and SGOT were significantly higher in the treated rats (2 and 4 mg/kg) than in the control group. A significant decrease in the level of hemoglobin and serum cholinesterase activity was observed, when there was an increase in the dose level. A significant increase was observed in alkaline phosphatase activity at all dose levels. Conclusion: Methomyl influences mixed function oxidase and creates abnormality of liver functions in the rats. This effect depends on the dose and duration of methomyl

Relation between material structure and photoluminescence properties in yttrium–aluminum borates phosphors

International audienceGlassy yttrium and aluminum borate powders (g-YAB) were synthesized by the polymeric precursor method (modified Pechini). We report here a detailed study of the structural, spectroscopic, and optical characterizations of the g-YAB powders, involving several complementary techniques: thermal analysis, X-ray powder diffraction, and electron microscopy combined with IR, nuclear magnetic resonance, and electron paramagnetic resonance spectroscopies. All these results, directly correlated with the photoluminescence (PL) properties of the g-YAB phosphors, allow us to argue that the PL emissions come from large polyaromatic molecules auto-generated from organic precursors and trapped in the glassy network of the g-YAB during thermal treatments. These extended aromatic molecules (seven rings and more corresponding to polycyclic aromatic hydrocarbons) must have been produced during the pyrolysis treatment of the powders, in which a large fraction of the protons was replaced during the calcination process by hydroxyl groups, or other oxygen-containing groups