Spectroscopic characterization of Al2O3-Ni selective absorbers for solar collectors

Cataloged from PDF version of article.Optical spectroscopy of electrochemically prepared Ni-pigmented aluminum oxide selective absorbers have been determined in the 200—20000 nm range. It was found that samples anodized under the same conditions and pigmented using nickel acetate resulted in better thermal emittance values when compared with nickel sulfate although both have comparable solar absorbance values. Electron spectroscopic investigation revealed that only a small fraction of Ni is present on the surface with an oxidation state of *#2. The O/Al ratio determined by XPS is larger than 1.5. This information together with the measured Al 2p Auger parameter indicated that the surfaces contain additional OH groups which was also confirmed by the presence of a broad hyrogen-bonded band in the region 3000—3400 cm~1 observed in the reflection—absorption IR spectra of these samples. ( 1998 Elsevier Science B.V. All rights reserved

Hemispheric Asymmetry in White Matter Connectivity of the Temporoparietal Junction with the Insula and Prefrontal Cortex

The temporoparietal junction (TPJ) is a key node in the brain's ventral attention network (VAN) that is involved in spatial awareness and detection of salient sensory stimuli, including pain. The anatomical basis of this network's right-lateralized organization is poorly understood. Here we used diffusion-weighted MRI and probabilistic tractography to compare the strength of white matter connections emanating from the right versus left TPJ to target regions in both hemispheres. Symmetry of structural connectivity was evaluated for connections between TPJ and target regions that are key cortical nodes in the right VAN (insula and inferior frontal gyrus) as well as target regions that are involved in salience and/or pain (putamen, cingulate cortex, thalamus). We found a rightward asymmetry in connectivity strength between the TPJ and insula in healthy human subjects who were scanned with two different sets of diffusion-weighted MRI acquisition parameters. This rightward asymmetry in TPJ-insula connectivity was stronger in females than in males. There was also a leftward asymmetry in connectivity strength between the TPJ and inferior frontal gyrus, consistent with previously described lateralization of language pathways. The rightward lateralization of the pathway between the TPJ and insula supports previous findings on the roles of these regions in stimulus-driven attention, sensory awareness, interoception and pain. The findings also have implications for our understanding of acute and chronic pains and stroke-induced spatial hemineglect

The history of neurosurgery in anatolia and turkey: The turkish neurosurgical society

Although the history of neurosurgery in Anatolia goes back ten thousand years, modern surgery began in Turkey in 1890. Neurosurgery in Turkey began in the first half of the 20th century. However, general surgeons began applying neurosurgical techniques back in the late 19th century. Most of these applications included procedures for craniocerebral traumas and infections. Dr. Cemil Topuzlu (1868-1958) is the founder of modern surgery in Turkey. Dr. Abdulkadir Cahit Tuner became the first neurosurgeon with a degree in Turkey in 1923. The first neurosurgery department was established in Istanbul in 1923, and the first training program began in the late 1940s. Currently there are almost 1200 neurosurgeons in Turkey and 75 training clinics at university hospitals and Training and Research Hospitals of the Ministry of Health provide neurosurgery training. The current state of neurosurgery in Turkey is parallel to that of the advanced Western countries. Apart from the application of neurosurgical procedures, there have been many scientific studies from Turkish neurosurgeons contributing to the total body of literature in neurosurgery

An investigation on the optimization of electrochemically pigmented aluminum oxide collector coatings

Cataloged from PDF version of article.In order to produce selective coatings on aluminium substrates to be used as absorber plates in high efficiency solar collectors, nickel pigmentation has been applied to anodically oxidized surfaces. Optical and structural properties of electrochemically formed aluminium oxide films as function of electrolysis conditions such as, applied current, pH, temperature and concentration of metal ions have been examined using electron spectroscopy and scanning electron microscopy. The optimisation of the absorptivity/emissivity ratio of the surfaces in terms of preparation conditions is described. Nickel pigmentation of porous aluminum surfaces was also investigated as a function of electrochemical pigmentation conditions. Mechanisms contributing to selectivity in anodically produced oxides and electrodeposits are discussed. Copyright © 1996 Published by Elsevier Science Ltd

Clastogenicity of selective serotonin-reuptake inhibitors

Objective: Selective serotonin-reuptake inhibitors (SSRIs) are used in the treatment of various forms of psychiatric disorders. Preclinical studies in laboratory animals have indicated that SSRIs were not genotoxic, but clear results from in vitro testing of SSRIs in a human cell system are currently scarce. The purpose of this study was to investigate whether SSRIs might be genotoxic. Sertraline was chosen as model SSRI, since it appears to be at least as well-tolerated as other SSRIs and may even have a more favourable side-effect profile. Unlike fluoxetine, fluvoxamine and paroxetine, sertraline has low potential for pharmacokinetic drug interactions. So, sertraline would be considered first in the treatment of psychiatric disorders requiring SSRI therapy in the future. We therefore examined peripheral lymphocytes from sertraline-treated patients for both sister chromatid exchanges (SCEs), cells with a high frequency of SCEs (HFC) and chromosome aberrations (CA) to evaluate the elastogenicity of SSRIs