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Another System (another + system)
Selected AbstractsHistory of hemodialyzers' designsHEMODIALYSIS INTERNATIONAL, Issue 2 2008Zbylut J. TWARDOWSKI Abstract Accumulation of knowledge requisite for development of hemodialysis started in antiquity and continued through Middle Ages until the 20th century. Firstly, it was determined that the kidneys produce urine containing toxic substances that accumulate in the body if the kidneys fail to function properly; secondly, it was necessary to discover the process of diffusion and dialysis; thirdly, it was necessary to develop a safe method to prevent clotting in the extracorporeal circulation; and fourthly, it was necessary to develop biocompatible dialyzing membranes. Most of the essential knowledge was acquired by the end of the 19th century. Hemodialysis as a practical means of replacing kidney function started and developed in the 20th century. The original hemodialyzers, using celloidin as a dialyzing membrane and hirudin as an anticoagulant, were used in animal experiments at the beginning of the 20th century, and then there were a few attempts in humans in the 1920s. Rapid progress started with the application of cellophane membranes and heparin as an anticoagulant in the late 1930s and 1940s. The explosion of new dialyzer designs continued in the 1950s and 1960s and ended with the development of capillary dialyzers. Cellophane was replaced by other dialyzing membranes in the 1960s, 1970s, and 1980s. Dialysis solution was originally prepared in the tank from water, electrolytes, and glucose. This solution was recirculated through the dialyzer and back to the tank. In the 1960s, a method of single-pass dialysis solution preparation and delivery system was designed. A large quantity of dialysis solution was used for a single dialysis. Sorbent systems, using a small volume of regenerated dialysis solution, were developed in the mid 1960s, and continue to be used for home hemodialysis and acute renal failure. At the end of the 20th century, a new closed system, which prepared and delivered ultrapure dialysis solution preparation, was developed. This system also had automatic reuse of lines and dialyzers and prepared the machine for the next dialysis. This was specifically designed for quotidian home hemodialysis. Another system for frequent home hemodialysis or acute renal failure was developed at the turn of the 21st century. This system used premanufactured dialysis solution, delivered to the home or dialysis unit, as is done for peritoneal dialysis. [source] Rendering: Input and OutputCOMPUTER GRAPHICS FORUM, Issue 3 2001H. Rushmeier Rendering is the process of creating an image from numerical input data. In the past few years our ideas about methods for acquiring the input data and the form of the output have expanded. The availability of inexpensive cameras and scanners has influenced how we can obtain data needed for rendering. Input for rendering ranges from sets of images to complex geometric descriptions with detailed BRDF data. The images that are rendered may be simply arrays of RGB images, or they may be arrays with vectors or matrices of data defined for each pixel. The rendered images may not be intended for direct display, but may be textures for geometries that are to be transmitted to be rendered on another system. A broader range of parameters now need to be taken into account to render images that are perceptually consistent across displays that range from CAVEs to personal digital assistants. This presentation will give an overview of how new hardware and new applications have changed traditional ideas of rendering input and output. [source] Two systems of resting state connectivity between the insula and cingulate cortexHUMAN BRAIN MAPPING, Issue 9 2009Keri S. Taylor Abstract The insula and cingulate cortices are implicated in emotional, homeostatic/allostatic, sensorimotor, and cognitive functions. Non-human primates have specific anatomical connections between sub-divisions of the insula and cingulate. Specifically, the anterior insula projects to the pregenual anterior cingulate cortex (pACC) and the anterior and posterior mid-cingulate cortex (aMCC and pMCC); the mid-posterior insula only projects to the posterior MCC (pMCC). In humans, functional neuroimaging studies implicate the anterior insula and pre/subgenual ACC in emotional processes, the mid-posterior insula with awareness and interoception, and the MCC with environmental monitoring, response selection, and skeletomotor body orientation. Here, we tested the hypothesis that distinct resting state functional connectivity could be identified between (1) the anterior insula and pACC/aMCC; and (2) the entire insula (anterior, middle, and posterior insula) and the pMCC. Functional connectivity was assessed from resting state fMRI scans in 19 healthy volunteers using seed regions of interest in the anterior, middle, and posterior insula. Highly correlated, low-frequency oscillations (< 0.05 Hz) were identified between specific insula and cingulate subdivisions. The anterior insula was shown to be functionally connected with the pACC/aMCC and the pMCC, while the mid/posterior insula was only connected with the pMCC. These data provide evidence for a resting state anterior insula,pACC/aMCC cingulate system that may integrate interoceptive information with emotional salience to form a subjective representation of the body; and another system that includes the entire insula and MCC, likely involved in environmental monitoring, response selection, and skeletomotor body orientation. Human Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source] Systems for accreditation in blood transfusion servicesISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue 1 2009S. Hindawi Accreditation is a non-governmental, voluntary process that evaluates institutions, agencies, and educational programs. It is defined as the process whereby an agency or association grants public recognition to Institutes or Blood Banks for having met certain established standards as determined through initial and periodic evaluations that usually involve submitting a self-evaluation report, site inspection by a team of experts, and evaluation by an independent board or commission. To be accredited Institution and or Blood Transfusion Services should establish and maintain quality systems involving all activities that determine the quality policy objectives & responsibilities taking into account the principles of good manufacturing practice (GMP). There are many Established systems for accreditation which can help any institution to know its strengths, weaknesses and opportunities through an informed review process. Any assessment and subsequent accreditation is made with reference to a set of standards so that the standing of an institution can be compared with that of other similar institutions. In summery the accreditation is a continuous process for improvement of quality and safety of participating institutes or facilities and we should encourage all health institutes to be involved in one or another system for accreditation. There is a need for a local or regional accreditation system for health institutes especially for blood transfusion services to help in the development and improvement of the quality of their services. [source] Agroecosystem modeling and optimal economic decisions: Implications for sustainable agricultureOPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 1 2008Craig A. Bond Abstract We adapt a biogeochemical model of an agroecosystem to account for optimal economic behavior on the part of agricultural producers. Two institutional management regimes are considered: one in which a representative producer does not account for stock pollution caused by use of agricultural inputs, and one in which the externality is internalized. Comparative statics of the steady state of the former problem are analyzed in order to gain insight into the effects of potential policy and technological changes. Results show that a more realistic ecosystem component that includes nutrient cycling can qualitatively change optimal management practices relative to a one-state representation, potentially rendering systems ,unsustainable' under some criteria and leading to policy instruments that exacerbate, rather than mitigate, external damages or the resource base. Moreover, the qualitative effect of changes in model parameters are not necessarily uniform across different agricultural systems, implying that a prescription for the so-called ,sustainable' management under one system may have unintended consequences under another system. Copyright © 2007 John Wiley & Sons, Ltd. [source] Woody Pretzels: Spirocycles from Vetiver to Patchouli and Georgywood®CHEMISTRY & BIODIVERSITY, Issue 6 2008Philip Kraft Abstract This review, including new experimental results, is the summary of a talk at the RSC/SCI conference ,flavours & fragrances 2007' in London, Imperial College, 24,26 September, 2007. Though the third dimension of the receptor models of J.,E. Amoore rarely was exceeding 4,Å, the world of woody odorants such as (+)-cedrol (3; cedarwood), (,)-khusimone (4; vetiver), and (,)-patchoulol (5; patchouli) is anything but flat. Any tricyclic skeleton with a zero-bridge contains a spirocyclic ring system determining its 3D structure, so spirocycles (spira, Lat. pretzel) are the fastest access to the third dimension. In the vetiver family, a spirocyclic mimic 9 of (,)-khusimone (4) was first discovered by chance by Büchi in 1976, and also by chance, we obtained another system, 12, with a characteristic vetiver smell by tandem- Rupe,Nazarov reaction of alkyne diols. A 5-Å distance between a quaternary C-atom and a carbonyl group (or alternative HB acceptor) with an , -methyl or methylene branching is proposed to be the key to their vetiver odor. Upon scale-up of one of these odorants, 24, we discovered a very powerful (0.067,ng/l) impurity with a most typical patchouli scent: the spirocyclic, sterically crowded hydroxy ketone 33 , a most unusual structure for a patchouli odorant. Several spirocyclic hydroxy ketone analogs, also with inverted ring systems such as in 70 and 84, provided new insights into the structure,odor correlation of this family. A superposition analysis indicated the carbonyl function of the hydroxy ketone to overlay on the geminal dimethyl motive of (,)-patchoulol. And indeed, the corresponding hydroxy ketone of patchoulol, 59, synthesized in 13 steps from Cyclal C (63), also emanated a patchouli odor. Finally, the synthesis and olfactory properties of twelve rigid spirocyclic analogs, 95,97, 99,102, and 106,110, of Georgywood® (91) are presented that highlight stereochemical requirements for woody odorants and raise doubts about an , -helical binding motive postulated by Hong and Corey. [source] | ||||||||||