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General Introduction (general + introduction)
Selected AbstractsSocial Networks and the Elderly: Conceptual and Clinical Issues, and a Family ConsultationFAMILY PROCESS, Issue 3 2000Carlos E. Sluzki M.D. After a general introduction to the construct "social networks," this article discusses the progressive transformation of the personal social network,family, friends and acquaintances, work and leisure relationships, et cetera,as individuals reach an advanced age. This is followed by a summary and discussion of a clinical consultation, with an emphasis on the reciprocal influence between individual and social network. [source] Aspects of stability and phenomenology in type IIA orientifolds with intersecting D6-branesFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 1 2004T. OttArticle first published online: 14 JAN 200 Abstract Intersecting branes have been the subject of an elaborate string model building for several years. After a general introduction into string theory, this work introduces in detail the toroidal and -orientifolds. The picture involving D9-branes with B-fluxes is shortly reviewed, but the main discussion employs the T-dual picture of intersecting D6-branes. The derivation of the R-R and NS-NS tadpole cancellation conditions in the conformal field theory is shown in great detail. Various aspects of the open and closed chiral and non-chiral massless spectrum are discussed, involving spacetime anomalies and the generalized Green-Schwarz mechanism. An introduction into possible gauge breaking mechanisms is given, too. Afterwards, both ,, = 1 supersymmetric and non-supersymmetric approaches to low energy model building are treated. Firstly, the problem of complex structure instabilities in toroidal ,R -orientifolds is approached by a -orbifolded model. In particular, a stable non-supersymmetric standard-like model with three fermion generations is discussed. This model features the standard model gauge groups at the same time as having a massless hypercharge, but possessing an additional global B - L symmetry. The electroweak Higgs mechanism and the Yukawa couplings are not realized in the usual way. It is shown that this model descends naturally from a flipped SU(5) GUT model, where the string scale has to be at least of the order of the GUT scale. Secondly, supersymmetric models on the -orbifold are discussed, involving exceptional 3-cycles and the explicit construction of fractional D-branes. A three generation Pati-Salam model is constructed as a particular example, where several brane recombination mechanisms are used, yielding non-flat and non-factorizable branes. This model even can be broken down to a MSSM-like model with a massless hypercharge. Finally, the possibility that unstable closed and open string moduli could have played the role of the inflaton in the evolution of the universe is being explored. In the closed string sector, the important slow-rolling requirement can only be fulfilled for very specific cases, where some moduli are frozen and a special choice of coordinates is taken. In the open string sector, inflation does not seem to be possible at all. [source] Verification process and its application to network traffic simulation modelsJOURNAL OF ADVANCED TRANSPORTATION, Issue 3 2002Ryota Horiguchi This paper summarizes a standardized verification process for network traffic simulation models. After the general introduction of philosophy of verification, we explain detailed processes of the verification and its application to several well-known simulation models. "Verification" here means several examination tests of simulation models using virtual data on a simple network so as to confirm their fundamental functions. In the course of model development, the developers have to examine whether the model performance is consistent with the specifications that they intend and also with the well-authorized traffic engineering theory. Because of several constraints in putting the model specifications into the computer programming such as discretizing of time and space and simplifying vehicle behaviors to some degree, the intended model specifications may not be fully achieved in a computer. Therefore, we strongly recommend the verification before applying the models to a real network. [source] Diode-pumped fiber lasers: A new clinical tool?LASERS IN SURGERY AND MEDICINE, Issue 3 2002Stuart D. Jackson PhD Abstract Background and Objective Diode-pumped fiber lasers are a compact and an efficient source of high power laser radiation. These laser systems have found wide recognition in the area of lasers as a result of these very practical characteristics and are now becoming important tools for a large number of applications. In this review, we outline the basic physics of fiber lasers and illustrate how a number of clinical procedures would benefit from their employment. Study Design/Materials and Methods The pump mechanisms, the relevant pump and laser transitions between the energy levels, and the main properties of the output from fiber lasers will be briefly reviewed. The main types of high power fiber lasers that have been demonstrated will be examined along with some recent medical applications that have used these lasers. We will also provide a general review of some important medical specialties, highlighting why these fields would gain from the introduction of the fiber laser. Results/Conclusion It is established that while the fiber laser is still a new form of laser device and hence not commercially available in a wide sense, a number of important medical procedures will benefit from its general introduction into medicine. With the number of medical and surgical applications requiring high power laser radiation steadily increasing, the demand for more efficient and compact laser systems providing this capacity will grow commensurately. The high power fiber laser is one system that looks like a promising modality to meet this need. Lasers Surg. Med. 30:184-190, 2002. © 2002 Wiley-Liss, Inc. [source] The mechanisms of collisional activation of ions in mass spectrometryMASS SPECTROMETRY REVIEWS, Issue 4 2009Paul M. Mayer Abstract This article is a review of the mechanisms responsible for collisional activation of ions in mass spectrometers. Part I gives a general introduction to the processes occurring when a projectile ion and neutral target collide. The theoretical background to the physical phenomena of curve-crossing excitation (for electronic and vibrational excitation), impulsive collisions (for direct translational to vibrational energy transfer), and the formation of long-lived collision intermediates is presented. Part II highlights the experimental and computational investigations that have been made into collisional activation for four experimental conditions: high (>100 eV) and intermediate (1,100 eV) center-of-mass collision energies, slow heating collisions (multiple low-energy collisions) and collisions with surfaces. The emphasis in this section is on the derived post-collision internal energy distributions that have been found to be typical for projectile ions undergoing collisions in these regimes. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:608,639, 2009 [source] A New Frontier in Soy Bioactive Peptides that May Prevent Age-related Chronic DiseasesCOMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 4 2005Wenyi Wang ABSTRACT During gastrointestinal digestion or food processing of proteins, small peptides can be released and may act as regulatory compounds with hormone-like activities. Numerous biologically active peptides (bioactive peptides) have been identified. Most bioactive peptides are derived from milk and dairy products, with the most common being angiotensin converting enzyme inhibitory peptides. Soybean protein and soybean derived peptides also play an important role in soybean physiological activities, particularly those related to the prevention of chronic diseases. However, the bioactive potential of soybean derived bioactive peptides is yet to be fully appreciated. After a general introduction of approaches and advances in bioactive peptides from food sources, this review focuses on bioactive peptides derived from soybean proteins and their physiological properties. Technological approaches to generate bioactive peptides, their isolation, purification, characterization, and quantification, and further application in food and drug design are also presented. Safety concerns, such as potential toxicity, allergenicity, and sensory aspect of these peptides are likewise discussed. [source] | ||||||||||