Recrystallization techniques for the synthesis of ZnO nanorods: an in situ process for carbon doping and enhancing the dispersion concentration of ZnO nanorods

Zinc acetate is recrystallized as lumber-shaped tetragonal rods by a novel recrystallization technique. Subsequently, the recrystallized zinc acetate is converted into ZnO nanorods in a glass vial by the simplest and cheapest method without utilizing any expensive instrumentation. Carbon is doped in ZnO nanorods during the preparation ZnO nanorods without any extra steps, chemicals, or effort. The carbon-doped ZnO nanorods can be dispersed in a solvent at very high concentrations and are also stable for a very long time, which are comparatively higher than those of the other existing ZnO nanoparticles. The higher dispersion concentration and higher stability of ZnO nanoparticles are explained by a scheme that demonstrates the suspending mechanism of the ZnO nanoparticles at higher concentrations with higher stabilities in a solvent through the anchoring groups of carbon. No materials are used for surface modification; no surface coatings, ionic materials, or pH controlling materials are used to increase the dispersion concentration and stability. This is the first observation of the doped carbon playing a significant role in the dispersion of ZnO nanoparticles at higher concentrations by withholding them in the solvent. Therefore, doped carbon at the surface of ZnO nanoparticles prevents the self-aggregation of ZnO nanoparticles in the solution phase by interfacial barrier layers among ZnO nanorods and interfacial interactive layer between ZnO nanorod and solvent.

Dispersed ZnO hexagonal nanorods in ethanol solvent and its interfacial behavior in this liquid phase.     

Congenital clavicular pseudoarthrosis associated with vascular thoracic outlet syndrome: Case presentation and review of the literature

Thoracic outlet syndrome (TOS) associated with congenital clavicular pseudoarthrosis is rare in adults and often misdiagnosed. In this case report, we describe an adult female who was found to have thromoosis of the subclavian and axillary arteries with embolization documented by invasive angiography. This unusual vascular manifestation of TOS should remind physicians that anatomic derangements may predispose to upper extremity ischemia. © 1995 Wiley-Liss, Inc.     

Treatment of variola major with cytosine arabinoside.

A controlled study of the efficacy of cytosine arabinoside in the treatment of patients with variola major was performed. Cytosine aravinoside was given intravenously at a dose approximating 3 mg/kg of body weight every 24 hr for up to seven days. All nine patients receiving cytosine arabinoside and four of the 11 patients receiving placebo died. In three of the patients receiving cytosine aravinoside, death occurred late in the illness at a time when the patient's lesions began to dry up, the patient's temperature became normal, and the patient's general condition appeared to improve. The virus could be isolated from the blood at day 7 from three of four patients treated with cytosine arabinoside as compared with zero of six control patients. Hematologic data showed a depression in the number of circulating granulocytes. It is possible that the drug lowered the resistance to infection either through direct suppression of granulocytes or through interference with other immune mechanisms. Cytosine arabinside administered in the doses used in this study is not effective in the treatment of variola major.     

Emergence and Distribution of Foot‐and‐Mouth Disease Virus Serotype A and O in Bangladesh

Foot‐and‐mouth disease (FMD) is endemic in Bangladesh and is predominantly due to FMDV serotype O. In 2012, FMD outbreaks were identified in five different districts of Bangladesh. Of 56 symptomatic cattle epithelial tissue samples, diagnostic PCR assay based on 5′‐URT detected 38 FMDV infections. Viral genotyping targeting VP1‐encoding region confirmed emergence of two distinct serotypes, A and O with an abundance of serotype A in Chittagong and Gazipur districts and serotype O in Pabna and Faridpur. Only single lineage of both A and O was retrieved from samples of five different regions. Sequencing and phylogenetic analysis of VP1 sequences revealed that serotype O sequences were closely related to the Ind 2001 sublineage of Middle East–South Asia (ME‐SA) topotype that was previously circulating in Bangladesh, and serotype A sequences belonging to the genotype VII that was dominant in India during the last decade. The results suggest that extensive cross‐border animal movement from neighbouring countries is the most likely source of FMDV serotypes in Bangladesh.     

Comparison of Long-Term Strength Development of Steel Fiber Shotcrete with Cast Concrete Based on Accelerator Type

This study analyzed the effect of accelerating agents, such as aluminate, cement mineral, and alkali-free accelerators, on the long-term performance of steel-fiber-reinforced shotcrete. The shotcrete performance was studied based on the type and amount of steel fiber added. Performance tests were performed to identify the accelerator providing better long-term performance to the steel-fiber-reinforced shotcrete. Changes in strength and flexural performance over time were investigated. The compressive strength and flexural strength tests on 1-, 3-, 6-, 12-, and 24-month-old test specimens were performed, wherein 37 kg of steel fiber was added to the cement mineral and aluminate mixes, and 40 kg of steel fiber was added to the alkali-free mix. The 1-month compressive strength result of all the test variables satisfied the Korea Expressway Corporation standard. The compressive strength of the cast concrete and shotcrete specimens increased with age, demonstrating a strength reduction, particularly in the 24-month-old shotcrete specimens. Thus, the shotcrete performance may deteriorate in the long-term. In the 24-month-old specimen, substantial flexural strength reduction was observed, particularly in the aluminate and alkali-free specimens. The relative strength of the specimens was compared with that of the cast concrete mold specimens. The results suggest the use of alkali-free accelerators, considering the long-term performance of tunnels and safety of workers. Moreover, increasing the steel fiber performance rather than the amount of low-performance steel fiber must be considered.