Stray light analysis for the Thomson scattering diagnostic of the ETE Tokamak

Thomson scattering is a well-established diagnostic for measuring local electron temperature and density in fusion plasma, but this technique is particularly difficult to implement due to stray light that can easily mask the scattered signal from plasma. To mitigate this problem in the multipoint Thomson scattering system implemented at the ETE (Experimento Tokamak Esfe?rico) a detailed stray light analysis was performed. The diagnostic system was simulated in ZEMAX software and scattering profiles of the mechanical parts were measured in the laboratory in order to have near realistic results. From simulation, it was possible to identify the main points that contribute to the stray signals and changes in the dump were implemented reducing the stray light signals up to 60 times.     

Apheresis Platelet Rich-Plasma for Regenerative Medicine: An In Vitro Study on Osteogenic Potential

Background: Platelet-Rich Plasma (PRP) induces bone regeneration; however, there is low evidence supporting its efficacy in bone healing. The lack of a standardized protocol of administration represents the main obstacle to its use in the clinical routine for bone defects’ treatment. The purpose of this study was to characterize PRP and elucidate its osteogenic potential. Methods: Platelet count, fibrinogen levels, and growth factors concentration were measured in PRP obtained by four apheresis procedures. HOB-01-C1, a pre-osteocytic cell line, was used to examine the effects of different PRP dilutions (from 1% to 50%) on cell viability, growth, and differentiation. Gene expression of RUNX2, PHEX, COL1A1, and OCN was also assayed. Results: PRP showed a mean 4.6-fold increase of platelets amount compared to whole blood. Among the 36 proteins evaluated, we found the highest concentrations for PDGF isoforms, EGF, TGF-β and VEGF-D. PDGF-AA positively correlated with platelet counts. In three of the four tested units, 25% PRP induced a growth rate comparable to the positive control (10% FBS); whereas, for all the tested units, 10% PRP treatment sustained differentiation. Conclusions: This study showed that PRP from apheresis stimulates proliferation and differentiation of pre-osteocyte cells through the release of growth factors from platelets.     

Anonymity in the global network — A first world dream

This may not read like a computer security article initially, that is, unless you also read between the lines! If, being a member of the digital community constantly involves you trying to avoid or divert a continuous onslaught of junk mail, or, manically trying to extricate yourself from listservs, then, this is a security issue.     

Electrical Transmission Characteristics of Marine Seismic Cable

The transmission line response of a marine seismic survey cable is analyzed. A new amplifier design yields significant improvement in compensating for the undesirable effects of the transmission line.     

Effect of low temperatures on polymorphic structures of cotton cellulose

Effects of low temperatures upon fine structures of cotton pretreated with either liquid ammonia or caustic of mercerizing strength were investigated. Temperatures of cotton after impregnation with liquid ammonia were lowered by (1) liquid nitrogen, (2) acetone–Dry Ice, (3) acetone, or (4) simple evaporation. With alkali-impregnated fabrics, temperature was lowered by immersion in liquid nitrogen. Changes in fine structure of ammonia- and alkali-celluloses were evaluated by x-ray diffraction before and after removal of each swelling reagent. After treatment with either ammonia or caustic soda, extent of crystalline modification was increased as temperature was reduced. X-ray diffractograms taken while liquid ammonia was still present indicated that the cellulose I structure of cotton sheeting was converted to cellulose III at liquid nitrogen temperatures; extent of conversion was approximately that obtained when a looser yarn structure was treated with liquid ammonia and the ammonia was removed by evaporation. When ammonia was removed with water, the cellulose I lattice was regenerated. In the presence of 23% NaOH, diffractograms indicated a significant decrease in order after a similar drop in temperature, but patterns were not of cellulose II until the NaOH was removed with water. Conversion to cellulose III or to cellulose II was achieved instantaneously when ammonia- and alkali-impregnated fabrics were immersed in liquid nitrogen.     

"Silent" gastroesophageal reflux and upper airway pathologies in childhood

In children, gastroesophageal reflux (GER) plays an important role in both acute and chronic upper airway disorders including stridor, chronic cough, recurrent upper respiratory infections, obstructive apnea, laryngospasm, and wheezing. Diagnosis may prove difficult unless there is reason to suspect GER and one is aware of the concept of "silent" GER. This paper presents our experience with chronic and/or recurrent respiratory disorders of uncertain origin and without gastrointestinal symptoms in children. Thirty-two pediatric patients with upper respiratory symptoms were evaluated. Out-patient 24-hour intraesophageal pH was monitored and 56% of the patients underwent pharyngo-laryngeal fibroscopy. The patients were divided into two subgroups: Group A (18 patients < 6 months of age) and Group B (14 patients > 6 months). All the patients tested positive for GER with a mean Reflux Index of 21.5. The most common symptoms in Group A were apnea-cianosis and stridor while they were chronic cough for group B. The present study confirms the association between GER and respiratory disease and between GER respiratory-related symptoms and patient age. Emphasis is placed on the importance of otolaryngological diagnostic procedures and 24-hour pH-gastroesophageal monitoring in evaluating patients with respiratory disorders related to silent GER.     

Surface morphology,tribological properties and in vitro biocompatibility of nanostructured zirconia thin films

Deposition of nanostructured and low-wear zirconia (ZrO₂) thin films on the metallic component of a total joint implant is envisaged to reduce wear of the soft ultra-high molecular weight polyethylene (UHMWPE) counterpart. In this work, morphological surface features, wear resistance and in vitro-biocompatibility of zirconia thin films deposited by the novel Pulsed Plasma Deposition (PPD) method have been investigated. Film thickness, roughness and wettability were found to be strongly dependent on deposition gas pressure. Interestingly, wear rate of UHMWPE disks coupled to zirconia-coated titanium spheres was only poorly correlated to the contact angle values, while film roughness and thickness seemed not to affect it. Furthermore, wear of UHMWPE, when coupled with zirconia coated-titanium spheres, significantly decreased with respect to uncoated spheres under dry or NaCl-lubricated conditions; besides, when using bovine serum, similar results were obtained for coated and uncoated spheres. Finally, suitable mesenchymal stem and osteoblast cells adhesion, proliferation and viability were observed, suggesting good biocompatibility of the nanostructured zirconia films. Taken together, the results shown in this work indicate that zirconia thin films deposited by the PPD method deserve further investigations as low-wear materials for biomedical applications such as total joint replacement.     

Network associate's McAfee online

Network Associate's McAfee Online is a multi-purpose resource site ideal for the IT manager who is not merely content with quarterly updates, but who wants cutting edge information on demand. The Virus Information Library http://vil.mcafee.com/villib contains detailed information on thousands of viruses — from whence they came, how they infect your system, and how to remove them.     

Ethics — The good fairy or an unnecessary extra burden?

There is a whole layer of awareness that comes before computer security. This is not a technical layer, but in many ways it is inextricably bound with things technical, especially with regard to security. This layer I am referring to comprises ethics. Ethics is important because of, or in spite of, computer security. You cannot have one without the other. On the one hand, if everyone was a valid user, or plying their trade honestly, and there were no abusers, ethics would have won the day, and we would all be upright, clean living citizens and netizens. Unfortunately, this One-Hundred-Acre Wood paradise does not exist. As the abusers become more adept, requiring the solutions to embrace increasingly complex issues, happy-ever-after Christopher Robin solutions are mere pipe dreams.