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Solid Basis (solid + basis)
Selected AbstractsRelationship between load/unload response ratio and damage variable and its applicationCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 12 2010Lang-Ping Zhang Abstract The physics-based parameter: load/unload response ratio (LURR) was proposed to measure the proximity of a strong earthquake, which achieved good results in earthquake prediction. As LURR can be used to describe the damage degree of the focal media qualitatively, there must be a relationship between LURR and damage variable (D) which describes damaged materials quantitatively in damage mechanics. Hence, based on damage mechanics and LURR theory, taking Weibull distribution as the probability distribution function, the relationship between LURR and D is set up and analyzed. This relationship directs LURR applied in damage analysis of materials quantitatively from being qualitative earlier, which not only provides the LURR method with a more solid basis in physics, but may also give a new approach to the damage evaluation of big scale structures and prediction of engineering catastrophic failure. Copyright © 2009 John Wiley & Sons, Ltd. [source] Tourism demand response by residents of Latin American countriesINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 1 2009Manuel Vanegas Sr Abstract A general-to-specific methodology was used to build international tourism demand models by residents from Argentina, Brazil, Colombia and Venezuela to Aruba. We seek to evaluate demand parameters, especially elasticity values, which were disaggregated on a country-to-country basis. We also aim to learn more about the structure and important variables and investigate the process of adjustment. The study has provided new and compelling evidence that, in the short run, residents in developing countries respond rationally and substantially to economic stimulus. The short-run income elasticity ranges from the low of 1.52 for Venezuela to the high of 2.34 for Argentina. These results indicate that Aruba will benefit differently from income increases in these four Latin American countries. The coefficients of the price variable had the expected negative signs, inelastic in the short-run for all countries but significant at the 5% level for Venezuela only. Any deliberate effort to expand tourist arrivals will require a much larger decline in prices than would be the case in the presence of short-run elastic response. The adjustment elasticity, being less than one, suggests that a period of more than one year is required for Latin American residents to fully adjust their tourism decisions in response to demand shocks. This study would seem to provide some useful information about international tourism demand from developing to developing countries that could form a very good and solid basis for analyses and policy action. Copyright © 2008 John Wiley & Sons, Ltd. [source] In Vivo Visualization of Senile-Plaque-Like Pathology in Alzheimer's Disease Patients by MR Microscopy on a 7T SystemJOURNAL OF NEUROIMAGING, Issue 2 2008Tsutomu Nakada MD ABSTRACT BACKGROUND Microscopic application of magnetic resonance imaging (MRI) has entered the era of clinical application. One of the most important targets is the visualization of pathological findings such as senile plaques (SP), in vivo, in patients with Alzheimer's disease (AD). Such an application provides not only the most accurate diagnostic tool for clinicians but also a solid basis for scientists for developing effective treatment and preventive strategies for AD. METHODS Focused microscopic studies were performed on parietal association cortex at the level of the centrum semiovale identified on conventional axial slices using a system constructed based on General Electric Signa LX (Waukesha, WI) equipped with a 900-mm clear bore superconducting magnet operating at 7.0 T in 10 patients (67-83-year old, five males, five females) who fulfilled the NINCD and the SADRDA criteria for probable AD, 10 age-matched controls (71-85-year old, five males, five females), and 20 young adults (22-35-year old, 10 males, 10 females) using a susceptibility weighted imaging (SWI) algorithm. RESULTS SWI microscopy consistently provided images with SP-like pathology extending within the entire parietal cortex in all cases of AD and 2 out of 10 age-matched volunteers. CONCLUSIONS Although the precise mechanisms leading to the higher susceptibility rendering SP-like pathology observable within the cortical mantle are not totally understood, the study unambiguously demonstrated that MR microscopy is capable of directly visualizing cortical pathology in AD patients in vivo. [source] Antennal sensilla of two parasitoid wasps: A comparative scanning electron microscopy studyMICROSCOPY RESEARCH AND TECHNIQUE, Issue 5 2004Maartje A.K. Bleeker Abstract Two closely related parasitoid wasp species, Cotesia glomerata (L.) and Cotesia rubecula (Marshall) (Hymenoptera:Braconidae), are different in their associative learning of plant odors. To provide a solid basis for our research on the mechanisms that underlie this difference, we described the morphology of the antennal sensilla of these two species using scanning electron microscopy complemented with transmission electron microscopy. Female and male antennae of both species have the same six types of sensilla. We classified these sensilla as sensilla trichodea without pores, sensilla trichodea with a tip pore, sensilla trichodea with wall pores, sensilla coeloconica type I, sensilla coeloconica type II, and sensilla placodea. We conclude that the morphology, numbers, and distribution of the sensory receptors are highly similar in these two closely related wasp species. Differences between species and sexes occurred only in sensilla placodea numbers. C. rubecula has more sensilla placodea than C. glomerata and males of both species have a larger number and a higher density of sensilla placodea compared to females of the same species. Microsc. Res. Tech. 63:266,273, 2004. © 2004 Wiley-Liss, Inc. [source] A network of net-workers: report of the Euresco conference on ,Bacterial Neural Networks' held at San Feliu (Spain) from 8 to 14 May 2004MOLECULAR MICROBIOLOGY, Issue 1 2004Klaas J. Hellingwerf Summary In May 2004, over 100 bacteriologists from 19 different countries discussed recent progress in identification and understanding of individual signal transfer mechanisms in bacteria and in the mutual interactions between these systems to form a functional living cell. The meeting was held in San Feliu and supported by ESF and EMBO. In part through the extensive sequencing efforts of the past few years, the bulk of the bacterial signal transfer systems have been resolved and their detailed characterization is revealing such characteristics as signal specificity, signalling rate constants, molecular interaction affinities, subcellular localization, etc., which should provide a solid basis to a computational extension of this field of studies. In parallel, the new genomics techniques are providing tools to characterize the way a collection of such systems interact in an individual cell, to give rise to ,life'. Systems theory provides rational and convenient ways to bring order to the wide range of observables thus obtained. Ultimately, the performance of engineered design will have to prove whether or not we know enough about the processes involved. [source] Plant regeneration through callus initiation from mature embryo of TriticumPLANT BREEDING, Issue 1 2007R. M. Bi Abstract The behaviour of diverse Triticum genotypes in the tissue culture response of mature embryo callus was compared, and factors affecting tissue culture response were studied in this paper. Significant differences were detected in callus induction, embryogenic callus differentiation, plantlet regeneration and culture efficiency when mature embryos of 31 plants of different Triticum species were compared. These were the main wheat cultivars of the Chinese northern winter-type wheat region and breeding lines (Triticum aestivum L.), durum wheat (Triticum durum Desf.), cultivable emmer wheat (Triticumdicoccum Schuble) and the common wheat progenitors Triticum dicoccoides and Triticum aegilopides. The genotype dependency was particularly high in tissue culture of mature embryos of these Triticum genotypes. The efficiency of induction, differentiation and regeneration of mature embryos callus was high in genotypes selected out. Mature embryo-derived callus of HB341, TS021, SN2618, T. dicoccum, HB188, and T9817 showed better tissue culture response than the other genotypes. Plantlets can be regenerated from mature embryo-derived callus of 31 genotypes, saving on growth facility resources and time required for the collection of other explants, and providing a solid basis for the genetic transformation and molecular plant breeding of Triticum plants. [source] The evolution of intelligence: adaptive specializations versus general processBIOLOGICAL REVIEWS, Issue 3 2001EUAN M. MAGPHAIL ABSTRACT Darwin argued that between-species differences in intelligence were differences of degree, not of kind. The contemporary ecological approach to animal cognition argues that animals have evolved species-specific and problem-specific processes to solve problems associated with their particular ecological niches: thus different species use different processes, and within a species, different processes are used to tackle problems involving different inputs. This approach contrasts both with Darwin's view and with the general process view, according to which the same central processes of learning and memory are used across an extensive range of problems involving very different inputs. We review evidence relevant to the claim that the learning and memory performance of non-human animals varies according to the nature of the stimuli involved. We first discuss the resource distribution hypothesis, olfactory learning-set formation, and the ,biological constraints' literature, but find no convincing support from these topics for the ecological account of cognition. We then discuss the claim that the performance of birds in spatial tasks of learning and memory is superior in species that depend heavily upon stored food compared to species that either show less dependence upon stored food or do not store food. If it could be shown that storing species enjoy a superiority specifically in spatial (and not non-spatial) tasks, this would argue that spatial tasks are indeed solved using different processes from those used in non-spatial tasks. Our review of this literature does not find a consistent superiority of storing over non-storing birds in spatial tasks, and, in particular, no evidence of enhanced superiority of storing species when the task demands are increased, by, for example, increasing the number of items to be recalled or the duration of the retention period. We discuss also the observation that the hippocampus of storing birds is larger than that of non-storing birds, and find evidence contrary to the view that hippocampal enlargement is associated with enhanced spatial memory; we are, however, unable to suggest a convincing alternative explanation for hippocampal enlargement. The failure to find solid support for the ecological view supports the view that there are no qualitative differences in cognition between animal species in the processes of learning and memory. We also argue that our review supports our contention that speculation about the phylogenetic development and function of behavioural processes does not provide a solid basis for gaining insight into the nature of those processes. We end by confessing to a belief in one major qualitative difference in cognition in animals: we believe that humans alone are capable of acquiring language, and that it is this capacity that divides our intelligence so sharply from non-human intelligence. [source] Werkzeug für die Chemische Biologie.CHEMIE IN UNSERER ZEIT (CHIUZ), Issue 3 2010Semisynthese Abstract Semisynthetische Verfahren haben einen großen Beitrag zu der rasanten Entwicklung geleistet, die auf dem noch jungen Feld der Chemischen Biologie in den letzten Jahren stattgefunden haben. Dabei haben beeindruckende Beispiele für die Semisynthese von komplexen modifizierten Proteinen sowie die Derivatisierung von Naturstoffen für biologische Studien nicht nur die Grenzen des Machbaren immer weiter verschoben, sondern auch tatsächlich effiziente Werkzeuge zur Erforschung von Proteinfunktionen etabliert. Gerade für Anwendungen in der Proteomik, das Studium zellulärer Zusammenhänge und ihrer Quantifizierung sind von semisynthetischen Ansätzen weitere Impulse zu erwarten. Dabei zeichnet sie besonders ein interdisziplinärer Charakter aus, der Chemie und Biologie verknüpft. Es ist zu erwarten, dass die wissenschaftliche Bedeutung dieser Verfahren weiter zunehmen wird. Semisynthetic techniques have greatly contributed to the rapid development of Chemical Biology in recent years. In this regard the semisynthesis of complex modified proteins as well as the selective derivatization of natural products has evolved into more than mere proof-of-principle concepts but powerful tools to probe protein functions. This technology provides a solid basis for further investigations on proteomics and qualitative and quantitative cell biology. The interdisciplinary charter bridging chemistry and biology is the hallmark of semisynthesis. It can be expected that its scientific impact will further increase in the future. [source] | |||||||||||||