Biodegradable Polylactic Acid (PLA) Microstructures for Scaffold Applications

In this research, we present a simple and cost effective soft lithographic process to fabricate PLA scaffolds for tissue engineering. In which, the negative photoresist JSR THB-120N was spun on a glass subtract followed by conventional UV lithographic processes to fabricate the master to cast the PDMS elastomeric mold. A thin poly(vinyl alcohol) (PVA) layer was used as a mode release such that the PLA scaffold can be easily peeled off. The PLA precursor solution was then cast onto the PDMS mold to form the PLA microstructures. After evaporating the solvent, the PLA microstructures can be easily peeled off from the PDMS mold. Experimental results show that the desired microvessels scaffold can be successfully transferred to the biodegradable polymer PLA.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing

China and the crisis : global power, domestic caution and local initiative

Even though the global crisis had a quick and dramatic impact on Chinese exports, the Chinese government responded with a range of policy responses that have helped maintain high rates of growth. This success has helped propel China to the centre of global politics, accelerating what many perceive to be a power shift from the West to China. But these gains were achieved by reversing policy in previous years designed to make a fundamental shift in China‟s mode of development, and have highlighted the problems associated with making such a transition. At the moment that many are looking at the Chinese "model" as a potential alternative to the Washington Consensus, one of the consequences of the crisis is to further question the long term efficacy of this "model" in China itself

Influence of Y-doped induced defects on the optical and magnetic properties of ZnO nanorod arrays prepared by low-temperature hydrothermal process

One-dimensional pure zinc oxide (ZnO) and Y-doped ZnO nanorod arrays have been successfully fabricated on the silicon substrate for comparison by a simple hydrothermal process at the low temperature of 90°C. The Y-doped nanorods exhibit the same c-axis-oriented wurtzite hexagonal structure as pure ZnO nanorods. Based on the results of photoluminescence, an enhancement of defect-induced green-yellow visible emission is observed for the Y-doped ZnO nanorods. The decrease of E(2)(H) mode intensity and increase of E(1)(LO) mode intensity examined by the Raman spectrum also indicate the increase of defects for the Y-doped ZnO nanorods. As compared to pure ZnO nanorods, Y-doped ZnO nanorods show a remarked increase of saturation magnetization. The combination of visible photoluminescence and ferromagnetism measurement results indicates the increase of oxygen defects due to the Y doping which plays a crucial role in the optical and magnetic performances of the ZnO nanorods

Static and non-static quantum effects in two-dimensional dilaton gravity

We study backreaction effects in two-dimensional dilaton gravity. The backreaction comes from an $R^2$ term which is a part of the one-loop effective action arising from massive scalar field quantization in a certain approximation. The peculiarity of this term is that it does not contribute to the Hawking radiation of the classical black hole solution of the field equations. In the static case we examine the horizon and the physical singularity of the new black hole solutions. Studying the possibility of time dependence we see the generation of a new singularity. The particular solution found still has the structure of a black hole, indicating that non-thermal effects cannot lead, at least in this approximation, to black hole evaporation.Comment: 10 pages, no figure

Sintesis Dan Karakterisasi Nano Powder Alumina Titania Dengan Metode Masking Gel Calcination

Nanopowder alumina titania (Al2O3.TiO2) telah terbentuk pada temperatur 1200 °C dengan metode masking-gel calcination. Tujuan penelitian ini adalah untuk melakukan sintesis dan karakterisasi nano powder alumina titania. Bahan-bahan yang digunakan adalah Al(OH)3, TiO2, asam sulfat, sukrosa dan ammonia. Metode masking gel calcination merupakan paten Balai Besar Keramik dengan nomor paten P00201000111. Metode ini merupakan modifikasi metode bottom up yang mengombinasikan proses fisika dan kimia yang dapat menghasilkan partikel berukuran nanometrik dengan distribusi ukuran partikel yang sempit. Hasil karakterisasi dengan X-RD, SEM, TEM dan PSA menunjukkan bahwa pada temperatur 1200 °C telah terbentuk nano powder alumina titania dengan ukuran partikel ≤ 30 nm, bentuk kristal silinder yang merupakan bentuk rutil dan rhombohedral yang merupakan bentuk dari α-Al2O3

Dexmedetomidine Related Bradycardia Leading to Cardiac Arrest in a Dog

A 2-year-old, mixed breed female dog (16 kg) underwent an exploratory laparotomy following ultrasonographic diagnosis of foreign body and a segment of small intestine intussusceptions. The patient was classified as an ASA II. Ketamine (1mg/kg, IV), and dexmedetomidine (2.5 µg/kg, IV), and morphine (0.6 mg/kg, SC) were given as anesthetic premedication. Propofol (0.1 mg/kg, IV) titrated to a total amount of 4 ml (2.5 mg/ kg) was given for intubation. Asystole was occurred. Cardiac resuscitation was then conducted immediately. Atipamezole (0.1 ml) was injected, but showed no response on ECG. Atropine (0.02 mg/kg) was then injected, and a second dosage was given. Two-three mins later, the heart rate at 84 beats/min. The NIBP showed 203/132 with MAP 153 mmHg, and the SpO2 showed 95% after the cardiac function was regained. Dexmedetomidine related bradycardia leading to cardiac arrest has been suggested in this case

Development of Taenia saginata asiatica metacestodes in SCID mice and its infectivity in human and alternative definitive hosts

Development of Taenia saginata asiatica metacestodes in SCID mice, and its infectivity in humans, golden hamsters, and Mongolian gerbils as alternative definitive hosts, were investigated. Cysticerci were recovered from SCID mice that were subcutaneously injected with hatched oncospheres of T. s. asiatica. The morphological changes of metacestodes were observed. The recovered cysticerci were fed to gerbils, hamsters and humans, to check for their infectivity. Tapeworms were recovered from gerbils and hamsters fed with 20 to 45 week-old cysticerci, and proglottids excretions were observed in human volunteers fed with 45 week-old cysticerci. However, no tapeworms were recovered from gerbils fed with 10 week-old cysticerci. Our results suggest that T. s. asiatica oncospheres needed more than 20 weeks to develop to maturity in SCID mice to be infective to both their natural and alternative definitive hosts

New high fill-factor triangular micro-lens array fabrication method using UV proximity printing

A simple and effective method to fabricate a high fill-factor triangular microlens array using the proximity printing in lithography process is reported. The technology utilizes the UV proximity printing by controlling a printing gap between the mask and substrate. The designed approximate triangle microlens array pattern can be fabricated the high fill-factor triangular microlens array in photoresist. It is due to the UV light diffraction to deflect away from the aperture edges and produce a certain exposure in photoresist material outside the aperture edges. This method can precisely control the geometric profile of high fill factor triangular microlens array. The experimental results showed that the triangular micro-lens array in photoresist could be formed automatically when the printing gap ranged from 240 micrometers to 840 micrometers. The gapless triangular microlens array will be used to increases of luminance for backlight module of liquid crystal displays.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/16838