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Multiplication
Kinds of Multiplication Terms modified by Multiplication Selected AbstractsMyosins of Babesia bovis: Molecular characterisation, erythrocyte invasion, and phylogenyCYTOSKELETON, Issue 4 2002A.E. Lew Abstract Using degenerate primers, three putative myosin sequences were amplified from Australian isolates of Babesa bovis and confirmed as myosins (termed Bbmyo-A, Bbmyo-B, and Bbmyo-C) from in vitro cultures of the W strain of B. bovis. Comprehensive analysis of 15 apicomplexan myosins suggests that members of Class XIV be defined as those with greater than 35% myosin head sequence identity and that these be further subclassed into groups bearing above 50,60% identity. Bbmyo-A protein bears a strong similarity with other apicomplexan myosin-A type proteins (subclass XIVa), the Bbmyo-B myosin head protein sequence exhibits low identity (35,39%) with all members of Class XIV, and 5,-sequence of Bbmyo-C shows strong identity (60%) with P. falciparum myosin-C protein. Domain analysis revealed five divergent IQ domains within the neck of Pfmyo-C, and a myosin-N terminal domain as well as a classical IQ sequence unusually located within the head converter domain of Bbmyo-B. A cross-reacting antibody directed against P. falciparum myosin-A (Pfmyo-A) revealed a zone of approximately 85 kDa in immunoblots prepared with B. bovis total protein, and immunofluorescence inferred stage-specific myosin-A expression since only 25% of infected erythrocytes with mostly paired B. bovis were immuno-positive. Multiplication of B. bovis in in vitro culture was inhibited by myosin- and actin-binding drugs at concentrations lower than those that inhibit P. falciparum. This study identifies and classifies three myosin genes and an actin gene in B. bovis, and provides the first evidence for the participation of an actomyosin-based motor in erythrocyte invasion in this species of apicomplexan parasite. Cell Motil. Cytoskeleton 52:202,220, 2002. © 2002 Wiley-Liss, Inc. [source] In Vivo Follicular Unit Multiplication: Is It Possible to Harvest an Unlimited Donor Supply?DERMATOLOGIC SURGERY, Issue 11 2006ERGIN ER MD BACKGROUND Follicular unit extraction is a process of removing one follicular unit at a time from the donor region. The most important limitation of this surgical procedure is a high transection rate. OBJECTIVE In this clinical study, we have transplanted different parts of transected hair follicle by harvesting with the follicular unit extraction technique (FUE) in five male patients. MATERIALS AND METHODS In each patient, three boxes of 1 cm2 are marked at both donor and recipient sites. The proximal one-third, one-half, and two-thirds of 15 hair follicles are extracted from each defined box and transplanted in recipient boxes. The density is determined at 12 months after the procedure. RESULTS A mean of 3 (range, 2,4) of the proximal one-third, 4.4 (range, 2,6) of the proximal one-half, and 6.2 (range, 5,8) of the proximal two-thirds of the transplanted follicles were observed as fully grown after 1 year. At the donor site, the regrowth rate was a mean of 12.6 (range, 10,14) of the proximal one-third, 10.2 (range, 8,13) of the proximal one-half, and 8 (range, 7,12) of the proximal two-thirds, respectively. CONCLUSION The survival rate of the transected hair follicles is directly related to the level of transection. Even the transected parts, however, can survive at the recipient site; the growth rate is not satisfactory and they are thinner than the original follicles. We therefore recommend that the surgeon not transplant the sectioned parts and be careful with the patients whose transection rate is high during FUE procedures. [source] Integration of Density Multiplication in the Formation of Device-Oriented Structures by Directed Assembly of Block Copolymer,Homopolymer BlendsADVANCED FUNCTIONAL MATERIALS, Issue 8 2010Guoliang Liu Abstract Non-regular, device-oriented structures can be directed to assemble on chemically nanopatterned surfaces such that the density of features in the assembled pattern is multiplied by a factor of two or more compared to the chemical pattern. By blending the block copolymers with homopolymers and designing the chemical pattern rationally, complicated structures such as bends, jogs, junctions, terminations, and combined structures are fabricated. Previously, directed assembly of block copolymers has been shown to enhance the resolution of lithographic processes for hexagonal arrays of spots and parallel lines, corresponding to the bulk morphologies of block copolymer systems, but this is the first demonstration of enhanced resolution for more complicated, device-oriented features. This fundamental knowledge broadens the range of technologies that can be served by the directed assembly of block copolymers. [source] Inhibited Long-Distance Movement of Potato Leafroll Virus to Tubers in Potato Genotypes Expressing Combined Resistance to Infection, Virus Multiplication and AccumulationJOURNAL OF PHYTOPATHOLOGY, Issue 9 2003J. Syller Abstract Plants of two potato clones which, in preliminary greenhouse assessments, showed resistance to multiplication and accumulation of potato leafroll virus (PLRV) were graft or aphid inoculated with the virus and grown in the greenhouse; plants of a moderately susceptible cultivar were used for comparison in all experiments. A high concentration of aphid-borne inoculum was used to ensure strong infection pressure. Clone M62759 appeared to be highly resistant to PLRV infection, whereas clone PS1706 was more susceptible. Both clones expressed a high level of resistance to virus multiplication, when primary or secondary infection was assayed by enzyme-linked immunosorbent assay. Moreover, PLRV was detected in only few or none of the progeny plants of clone M62759, which thus strongly inhibited virus transport to tubers. The study on PLRV translocation from aphid-inoculated shoots to uninoculated shoots sprouted from the same tubers showed that no specific mechanisms are likely to impair PLRV movement through the tubers of the resistant genotypes. These results indicate that three valuable components of the resistance to PLRV are probably closely linked in the genotype, a combination that seems to occur rather rarely in potato clones. Nevertheless, selecting potato genotypes for the complex resistance to PLRV may prove to be a worthwhile part of breeding programmes, provided that the genetic mechanisms governing particular types of resistance are better recognized. [source] Developmental Change and Individual Differences in Children's MultiplicationCHILD DEVELOPMENT, Issue 4 2003Donald J. Mabbott Age-related change and patterns of individual differences in children's knowledge and skill in multiplication were investigated for students in Grades 4 and 6 (approximately ages 9 and 11, respectively) by examining multiple measures of computational skill, conceptual knowledge, and working memory. Regression analyses revealed that indexes reflecting probability of retrieval and special problem characteristics overshadow other, more general indexes (problem size and frequency of presentation) in predicting solution latencies. Some improvement in the use of conceptual knowledge was evident between Grades 4 and 6, but this change was neither strong nor uniform across tasks. Finally, patterns of individual differences across tasks differed as a function of grade level. The findings have implications for understanding developmental change and individual differences in mathematical cognition. [source] Determination of effective anisotropy in nanocrystalline soft ribbons regarding magnetostrictive contributionsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 1 2003O. Geoffroy Abstract The effective anisotropy of nanocrystalline ribbons was determined by means of breakage/multiplication of domain walls by eddy currents under dynamical conditions. The data were interpreted in terms of the possible sources of anisotropy: random crystalline (nanograins), uniaxial (field annealing), magnetoelastic (stress). A simple model adapted from Herzer's Random Anisotropy Model describes the combination of the above terms on the wall scale. The random contribution from nanograins is short-range and averaged by the walls. On the contrary, the two other terms are long-range. The estimated stress ranges between 0.3 and 1.3 MPa, depending on the degree of recrystallisation. [source] Full waveform seismic inversion using a distributed system of computersCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 11 2005Indrajit G. Roy Abstract The aim of seismic waveform inversion is to estimate the elastic properties of the Earth's subsurface layers from recordings of seismic waveform data. This is usually accomplished by using constrained optimization often based on very simplistic assumptions. Full waveform inversion uses a more accurate wave propagation model but is extremely difficult to use for routine analysis and interpretation. This is because computational difficulties arise due to: (1) strong nonlinearity of the inverse problem; (2) extreme ill-posedness; and (3) large dimensions of data and model spaces. We show that some of these difficulties can be overcome by using: (1) an improved forward problem solver and efficient technique to generate sensitivity matrix; (2) an iteration adaptive regularized truncated Gauss,Newton technique; (3) an efficient technique for matrix,matrix and matrix,vector multiplication; and (4) a parallel programming implementation with a distributed system of processors. We use a message-passing interface in the parallel programming environment. We present inversion results for synthetic and field data, and a performance analysis of our parallel implementation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Neuronismo y reticulismo: neuronal,glial circuits unify the reticular and neuronal theories of brain organizationACTA PHYSIOLOGICA, Issue 1 2009A. Verkhratsky Abstract The neuronal doctrine, which shaped the development of neuroscience, was born from a long-lasting struggle between reticularists, who assumed internal continuity of neural networks and neuronists, who defined the brain as a network of physically separated cellular entities, defined as neurones. Modern views regard the brain as a complex of constantly interacting cellular circuits, represented by neuronal networks embedded into internally connected astroglial syncytium. The neuronal,glial circuits endowed with distinct signalling cascades form a ,diffuse nervous net' suggested by Golgi, where millions of synapses belonging to very different neurones are integrated first into neuronal,glial,vascular units and then into more complex structures connected through glial syncytium. These many levels of integration, both morphological and functional, presented by neuronal,glial circuitry ensure the spatial and temporal multiplication of brain cognitive power. [source] Characterization of dislocation structures in copper single crystals using electron channelling contrast technique in SEMCRYSTAL RESEARCH AND TECHNOLOGY, Issue 3 2009Xiao-Wu Li Abstract The dislocation structures induced by low-plastic-strain-amplitude cyclic deformation of [111] multiple-slip-oriented Cu single crystals were investigated using electron channelling contrast (ECC) technique in scanning electron microscopy (SEM). At a low plastic strain amplitude ,pl of 8.8 × 10,5, the saturated dislocation structure is mainly composed of labyrinth-like vein structure (or irregular labyrinths), and the cyclic hardening behavior at such a low ,pl is interpreted as being the result of dislocation multiplication by a Frank-Read mechanism. As ,pl increases to 4.0 × 10,4, the unsaturated dislocation structure exhibits two kinds of distinctive configurations, i.e., dislocation walls and misoriented cells. Interestingly, these misoriented dislocation cells are strictly aligned along the primary slip plane (111), constituting a unique persistent slip band (PSB) structure. Here, these cells are thus called PSB cells. In addition, there is a locally distinctive region comprising some cells having a recrystallization-like feature in the whole structure of PSB cells. The formation of the structure of PSB cells is discussed. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A report from the international consensus on diagnosing and treating the infected diabetic foot,DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue S1 2004Benjamin A. Lipsky Chairman Abstract In persons with diabetes, foot infection, that is, invasion and multiplication of microorganisms in tissues accompanied by tissue destruction or a host inflammatory response, usually begins with skin trauma or ulceration 1. While most foot infections remain superficial, they can spread to subcutaneous tissues, including muscle, joints, and bone. Many diabetic foot ulcers eventuate in an amputation; infection plays a role in approximately 60% of cases 2,4. Neuropathy is the main factor leading to skin breaks, while arterial perfusion largely affects infection outcome. Among the factors predisposing diabetic patients to foot infections are ill-defined immunological perturbations 5, 6; foot anatomy may foster proximal spread of infection and ischemic necrosis 7, 8. Copyright © 2004 John Wiley & Sons, Ltd. [source] The Need to Look Beyond the Production and Provision of Relief Seed: Experiences from Southern SudanDISASTERS, Issue 4 2002Richard B. Jones Free distribution of seeds in selected areas of southern Sudan has been widespread as a way of increasing food security. Field research in areas targeted for seed relief found that farmer seed systems continue to meet the crop and varietal needs of farmers even following the 1998 famine. Donor investments in seed multiplication of improved sorghum have not been sustained due to a lack of effective demand for the improved seed beyond that created by the relief agencies. The article argues that rather than imposing outside solutions, whether through seed provisioning or seed production enterprises, greater attention needs to be given to building on the strengths of existing farmer systems and designing interventions to alleviate the weaknesses. The case is made to support dynamically the process of farmer experimentation through the informed introduction of new crops and varieties that can potentially reinforce the strength and diversity of local cropping systems. [source] Ultrastructural and immunocytochemical observations of the nervous systems of three macrodasyidan gastrotrichsACTA ZOOLOGICA, Issue 3 2003R. Hochberg Abstract The nervous systems of three macrodasyidan gastrotrichs, Dactylopodola baltica, Macrodasys caudatus and Dolichodasys elongatus, were investigated using immunocytochemistry and electron microscopy. Labelling of neural structures against serotonin revealed the presence of two pairs of cerebral cells, a dorsal cerebral connective, and paired ventral nerve cords in D. baltica. In M. caudatus and D. elongatus serotonin immunoreactivity was present in a single pair of dorsal cerebral cells and the ventral nerve cords; the dorsal connective of D. elongatus was also immunoreactive to serotonin and acetylated ,-tubulin. The presence of paired, serotonin-like immunoreactive cells in D. baltica and other species may represent the plesiomorphic condition in Macrodasyida. The fine structure of the photoreceptors in D. baltica was also investigated to explore the potential ground pattern for eyes in the Macrodasyida. The pigmented photoreceptors of D. baltica contain a unicellular pigment cup, sheath cell and sensory receptor. The pigment cup contains numerous osmiophilic granules that presumably function to shield the eyes from downwelling light in the red part of the spectrum. Projecting into the pigment cup and sheath cell are numerous microvilli from a bipolar sensory cell. A single sensory cell may represent the plesiomorphic condition in Macrodasyida, with multiplication of sensory cells representative of more derived taxa. [source] Salient virulence factors in anaerobic bacteria, with emphasis on their importance in endodontic infectionsENDODONTIC TOPICS, Issue 1 2004Ingar Olsen Endodontic infections by microbial invasion of the necrotic pulp lead to apical periodontitis of both acute and chronic forms. Acute lesions often develop from multiplication of bacteria in primary infections. Such lesions may also occur as exacerbations of chronic forms provoked for example in conjunction with endodontic treatment measures. The clinical course appears related to the character of the microflora. While primary infections are predominated by a mixed flora of anaerobic bacteria and resembles that of aggressive marginal periodontitis, chronic forms of apical periodontitis emerge following regression of the acute infection, whereupon prevailing bacteria have assumed low activity. The significance of virulence factors is easy to understand as far as acute inflammatory conditions are concerned. The role of virulence factors for sustaining chronic inflammation is more unclear and complex. This review is about salient virulence factors in some selected bacterial genera such as Peptostreptococcus, Porphyromonas, Prevotella and Fusobacterium, which often predominate the root canal microbiota in the acute phase of endodontic infections. [source] The Current Status and Prospects of the ,Strategic Partnership' between the EU and China: Towards the Conclusion of a Partnership and Cooperation AgreementEUROPEAN LAW JOURNAL, Issue 6 2007Antoine Sautenet In the absence of a category of ,emerging countries' in international economic law, the Union must adapt its foreign policy with regard to this major economic and commercial power. Relations between the European Community and China are currently governed by a second-generation agreement from 1985. However, a new dynamic has been set in motion since 2003, by the drawing up of preparatory documents by both parties and joint declarations at annual summits bearing on the ,strategic partnership'. Seen in a long-term perspective, this partnership helps provide a measure of predictability in relations between the two partners, through combining elements of ,soft law' and ,hard law'. If the insertion of political dialogue into the strategic partnership seems to alter the coherence of the Union, notably with regard to the difficulties of implementing the dialogue on human rights, the added value of the partnership lies essentially in its economic and commercial aspects, through not only the putting into place of non-binding ,economic dialogues' which cover a large spectrum of the relationship, but also by the multiplication of sector-based accords in numerous areas (maritime transport, customs cooperation, etc.). This constant development has thus allowed parties, at the last annual summit, to envisage the conclusion of a new framework agreement: this is the origin of the mandate given to the Commission in December 2005 to conclude a partnership and cooperation agreement. This article will sketch out a forecast of the legal framework, measured against the yardsticks of Asiatic regional reconfigurations and the law of the World Trade Organisation (WTO). The commercial risks of the relationship could imply the integration of the domains known as ,WTO plus' into the future agreement, notably in the field of investments and intellectual property rights, which would introduce a greater variety into the agreement. That being the case, the negotiations risk being equally fragile at the political level, in particular concerning the insertion of a clause of democratic conditionality in the future agreement. Also, any clash between the values and the interests of the EU would be uncomfortably highlighted during negotiations. [source] Enhanced survival of vascular smooth muscle cells accounts for heightened elastin deposition in arteries of neonatal spontaneously hypertensive ratsEXPERIMENTAL PHYSIOLOGY, Issue 4 2010Silvia M. Arribas Abnormal stiffening and narrowing of arteries are characteristic features of spontaneously hypertensive rats (SHR). In this strain, we have previously demonstrated an increased elastin content and abnormal organization of lamellae in conduit and resistance arteries from neonatal rats that preceded the impending inward remodelling, increased vascular stiffness and development of hypertension. The aim of this study was to assess the mechanism responsible for such excessive and aberrant elastin deposition in SHR vessels during perinatal development. We compared elastin, collagen and fibronectin production (inmunocytochemistry and quantitative assay of metabolically labelled insoluble elastin), DNA content as well as cell proliferation (proliferative cellular nuclear antigen, bromodeoxyuridine incorporation) and death rates (propidium iodide exclusion test, terminal transferase nick and labeling (TUNEL) assay) in cultures of vascular smooth muscle cells (VSMC) derived from neonatal SHR and Wistar,Kyoto (WKY) control rats. Cultures of VSMC derived from neonatal SHR exhibited hypertrophy, produced more elastin, collagen and fibronectin and contained more DNA than equally plated WKY counterparts. Further analysis revealed that the higher net DNA content in SHR-derived cultures was due to increased diploidy, but not to a heightened cell multiplication. The SHR-derived VSMC also exhibited lower rates of cell death and apoptosis, which were associated with increased levels of the anti-apoptotic protein, survivin. We therefore conclude that the peculiar heightened survival of matrix-producing VSMC in neonatal SHR is responsible for accumulation of hard-wearing elastin and other extracellular matrix elements in the growing arteries, thereby contributing to the subsequent development of systemic hypertension. [source] Sexual or clonal origin?FEDDES REPERTORIUM, Issue 3-4 2005A morpho-ecological, molecular analysis in a patch of Ajuga reptans L. (Lamiaceae) Spatial clonal structure and patch colonisation in Ajuga reptans L. (Lamiaceae), a common stoloniferous semi-rosette plant, were studied using a combined morpho-ecological and molecular genetic approach. Within a natural patch from a forest near Diedorf (Thuringia, Germany), the spatial clonal structure was analysed, correlating both datasets: Morphologically, characteristics of clonal growth and clonal reproduction were studied, the spatial distribution of modules was mapped and merigenet relationships were reconstructed. Samples from the patch and its surroundings, and an additional sample from Berlin were then analysed by AFLP fingerprinting using four different primer combinations to identify genets. Most divergence in banding patterns was already obtained for samples from the Diedorf forest. Within the patch, however, most samples had very similar fingerprints, indicating their belonging to the same genet and hence a clonal origin, although they are morphologically separated into three "plants". Based on AFLP data, the relationships of one sample remained ambiguous; but the correlation with morphological data helped to interpret the pattern and indicated that the sample is probably a dividual of the clone, too. The relevance of the observed vegetative multiplication (clonal growth and subsequent clonal reproduction) for patch colonisation and maintenance are discussed. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Generativer (sexueller) oder klonaler Ursprung? Eine morpho-ökologische und molekulare Analyse in einem ,patch' von Ajuga reptans L. (Lamiaceae) Die räumliche klonale Struktur und die ,patch' Besiedlung von Ajuga reptans L. (Lamiaceae), einer häufigen Halbrosettenpflanze mit Ausläufern, wurden mit einem morpho-ökologischen und molekular-genetischen Ansatz kombiniert analysiert. Die Untersuchung wurde in einem ,patch' aus einem Wald bei Diedorf (Thüringen) durchgeführt: Morphologisch wurden Merkmale des klonalen Wachstums und der klonalen Reproduktion untersucht, die räumliche Verteilung der Module kartiert und Merigenet-Beziehungen rekonstruiert. Für Proben aus dem ,patch', aus dessen näherer Umgebung und einer Pflanze aus Berlin wurden AFLP Analysen mit vier verschiedenen Primer-Kombinationen durchgeführt, um genetische Individuen (Genets) zu identifizieren. Die meisten Unterschiede in den Fragmentmustern zeigten sich bereits zwischen Proben aus Diedorf. Die ,patch'-Proben (morphologisch aufgeteilt in drei "Pflanzen") hatten jedoch sehr ähnliche fingerprints, was ihre Zugehörigkeit zum selben Genet und eine klonale Abstammung belegt. Für eine Probe ließen sich die Verwandtschaftsbeziehungen mit den AFLP Daten nicht sicher klären. Der Abgleich mit den morphologischen Ergebnissen ermöglichte jedoch eine Interpretation, und deutet auf die Zugehörigkeit zum Klon. Die Bedeutung der "vegetativen Multiplikation" (durch klonales Wachstum und klonale Reproduktion) für die Besiedlung und dauerhafte Besetzung von ,patches' wird diskutiert. [source] On the existence of non-supersymmetric black hole attractors for two-parameter Calabi-Yau's and attractor equationsFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 12 2006P. Kaura We look for possible nonsupersymmetric black hole attractor solutions for type II compactification on (the mirror of) CY3(2,128) expressed as a degree-12 hypersurface in WCP4[1,1,2,2,6]. In the process, (a) for points away from the conifold locus, we show that the existence of a non-supersymmetric attractor along with a consistent choice of fluxes and extremum values of the complex structure moduli, could be connected to the existence of an elliptic curve fibered over C8 which may also be "arithmetic" (in some cases, it is possible to interpret the extremization conditions for the black-hole superpotential as an endomorphism involving complex multiplication of an arithmetic elliptic curve), and (b) for points near the conifold locus, we show that existence of non-supersymmetric black-hole attractors corresponds to a version of A1 -singularity in the space Image(Z6,R2/Z2 (,R3)) fibered over the complex structure moduli space. The (derivatives of the) effective black hole potential can be thought of as a real (integer) projection in a suitable coordinate patch of the Veronese map: CP5,CP20, fibered over the complex structure moduli space. We also discuss application of Kallosh's attractor equations (which are equivalent to the extremization of the effective black-hole potential) for nonsupersymmetric attractors and show that (a) for points away from the conifold locus, the attractor equations demand that the attractor solutions be independent of one of the two complex structure moduli, and (b) for points near the conifold locus, the attractor equations imply switching off of one of the six components of the fluxes. Both these features are more obvious using the attractor equations than the extremization of the black hole potential. [source] Time-domain approach to linearized rotational response of a three-dimensional viscoelastic earth model induced by glacial-isostatic adjustment: I. Inertia-tensor perturbationsGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2005k Martinec SUMMARY For a spherically symmetric viscoelastic earth model, the movement of the rotation vector due to surface and internal mass redistribution during the Pleistocene glaciation cycle has conventionally been computed in the Laplace-transform domain. The method involves multiplication of the Laplace transforms of the second-degree surface-load and tidal-load Love numbers with the time evolution of the surface load followed by inverse Laplace transformation into the time domain. The recently developed spectral finite-element method solves the field equations governing glacial-isostatic adjustment (GIA) directly in the time domain and, thus, eliminates the need of applying the Laplace-domain method. The new method offers the possibility to model the GIA-induced rotational response of the Earth by time integration of the linearized Liouville equation. The theory presented here derives the temporal perturbation of the inertia tensor, required to be specified in the Liouville equation, from time variations of the second-degree gravitational-potential coefficients by the MacCullagh's formulae. This extends the conventional approach based on the second-degree load Love numbers to general 3-D viscoelastic earth models. The verification of the theory of the GIA-induced rotational response of the Earth is performed by using two alternative approaches of computing the perturbation of the inertia tensor: a direct numerical integration and the Laplace-domain method. The time-domain solution of both the GIA and the induced rotational response of the Earth is readily combined with a time-domain solution of the sea level equation with a time-varying shoreline geometry. In a follow-up paper, we derive the theory for the case when GIA-induced perturbations in the centrifugal force affect not only the distribution of sea water, but also deformations and gravitational-potential perturbations of the Earth. [source] Assessing yield and yield stability of remnant populations of Cenchrus ciliaris L. in arid Tunisia: developing a blueprint for initiating native seed productionGRASS & FORAGE SCIENCE, Issue 3 2008M. Visser Abstract Native seed needs to be sourced locally yet contain ample genetic variation. A blueprint is developed for assembling and assessing native plant material at one eco-geographical site prior to seed multiplication for restoring degraded drylands of North Africa. To satisfy the ,local yet ample' criterion, the feasibility of selecting a limited number of high-yielding genotypes within one starter collection of Cenchrus ciliaris L. in Presaharian Tunisia (100,200 mm annual rainfall) was tested and compared to outcomes with similar work on its ecological complement, Stipa lagascae R. & Sch. Results showed that a limited number of high-yielding genotypes can easily produce quality native seed because of the high genetic diversity of the starter material. Results also showed that there was a high potential to increase the rain-use efficiency of degraded drylands using this seed. Seven ground rules are suggested when building the starter collection: (i) carefully delimit the region for sourcing seed; (ii) work with individual plants; (iii) carefully choose the collection site; (iv) replicate plant material as much as is feasible; (v) match evaluation methods to resource constraints; (vi) wait for conditions of maximum resource availability before culling; and (vii) apply a two-tiered selection strategy. [source] Cyclosporin A suppresses replication of hepatitis C virus genome in cultured hepatocytesHEPATOLOGY, Issue 5 2003Koichi Watashi Persistent infection of hepatitis C virus (HCV) is a major cause of liver diseases such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Searching for a substance with anti-HCV potential, we examined the effects of a variety of compounds on HCV replication using a HCV subgenomic replicon cell culture system. Consequently, the immunosuppressant cyclosporin A (CsA) was found to have a suppressive effect on the HCV replicon RNA level and HCV protein expression in these cells. CsA also inhibited multiplication of the HCV genome in a cultured human hepatocyte cell line infected with HCV using HCV-positive plasma. This anti-HCV activity of CsA appeared to be independent of its immunosuppressive function. In conclusion, our results suggest that CsA may represent a new approach for the development of anti-HCV therapy. [source] Fast multipole boundary element analysis of two-dimensional elastoplastic problemsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 10 2007P. B. Wang Abstract This paper presents a fast multipole boundary element method (BEM) for the analysis of two-dimensional elastoplastic problems. An incremental iterative technique based on the initial strain approach is employed to solve the nonlinear equations, and the fast multipole method (FMM) is introduced to achieve higher run-time and memory storage efficiency. Both of the boundary integrals and domain integrals are calculated by recursive operations on a quad-tree structure without explicitly forming the coefficient matrix. Combining multipole expansions with local expansions, computational complexity and memory requirement of the matrix,vector multiplication are both reduced to O(N), where N is the number of degrees of freedom (DOFs). The accuracy and efficiency of the proposed scheme are demonstrated by several numerical examples. Copyright © 2006 John Wiley & Sons, Ltd. [source] Evaluating recursive filters on distributed memory parallel computersINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 11 2006Przemys, aw Stpiczy, skiArticle first published online: 6 APR 200 Abstract The aim of this paper is to show that the recently developed high performance divide and conquer algorithm for solving linear recurrence systems with constant coefficients together with the new BLAS-based algorithm for narrow-banded triangular Toeplitz matrix,vector multiplication, allow to evaluate linear recursive filters efficiently on distributed memory parallel computers. We apply the BSP model of parallel computing to predict the behaviour of the algorithm and to find the optimal values of the method's parameters. The results of experiments performed on a cluster of twelve dual-processor Itanium 2 computers and Cray X1 are also presented and discussed. The algorithm allows to utilize up to 30% of the peak performance of 24 Itanium processors, while a simple scalar algorithm can only utilize about 4% of the peak performance of a single processor. Copyright © 2006 John Wiley & Sons, Ltd. [source] Iterative solution of large linear systems with non-smooth submatrices using partial wavelet transforms and split-matrix matrix,vector multiplicationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2004Patricia González Abstract The iterative solution of large linear systems with highly irregular matrices cannot be accelerated by wavelet transformation and subsequent sparsification if the transformed matrix is still highly irregular. In this paper we show that if the irregularity of the original matrix is limited to a relatively small known set of rows or columns (as is the case in significant applications), then acceleration can be achieved by a mixed approach in which only the ,smooth' submatrix is transformed and iterative solution is implemented using a novel ,split-matrix' form of matrix,vector multiplication. Copyright © 2003 John Wiley & Sons, Ltd. [source] An orthotropic damage model for masonry structuresINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 2 2002Luisa Berto Abstract An orthotropic damage model specifically developed for the analysis of brittle masonry subjected to in-plane loading is described. Four independent internal damage parameters, one in compression and one in tension for each of the two natural axes of the masonry, are defined allowing the stiffness recovery at crack closure as well as the different inelastic behaviour along each natural axis to be considered. The damage field of the material is defined in terms of four equivalent stresses and results, in the space of the in-plane effective stresses, in a double pyramid with a rectangular base where the slopes of the faces correspond to the internal friction angle of the material. The equivalent stresses also control the growth of the damage parameters. The returning path from the effective to the damaged stresses is given by multiplication by a fourth-rank damage effect tensor, which is a function of the damage parameters and of the effective stress state. Mesh size regularization is achieved by means of an enhanced local method taking into account the finite element size. Good agreement has been found in the comparison between numerical results and experimental data both for masonry shear panels and for a large-scale masonry holed wall. Copyright © 2002 John Wiley & Sons, Ltd. [source] Adaptive integral method combined with the loose GMRES algorithm for planar structures analysisINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 1 2009W. Zhuang Abstract In this article, the adaptive integral method (AIM) is used to analyze large-scale planar structures. Discretization of the corresponding integral equations by method of moment (MoM) with Rao-Wilton-Glisson (RWG) basis functions can model arbitrarily shaped planar structures, but usually leads to a fully populated matrix. AIM could map these basis functions onto a rectangular grid, where the Toeplitz property of the Green's function would be utilized, which enables the calculation of the matrix-vector multiplication by use of the fast Fourier transform (FFT) technique. It reduces the memory requirement from O(N2) to O(N) and the operation complexity from O(N2) to O(N log N), where N is the number of unknowns. The resultant equations are then solved by the loose generalized minimal residual method (LGMRES) to accelerate iteration, which converges much faster than the conventional conjugate gradient method (CG). Furthermore, several preconditioning techniques are employed to enhance the computational efficiency of the LGMRES. Some typical microstrip circuits and microstrip antenna array are analyzed and numerical results show that the preconditioned LGMRES can converge much faster than conventional LGMRES. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009. [source] A survey for serotyping, antibiotic resistance profiling and PFGE characterization of and the potential multiplication of restaurant Salmonella isolatesJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2007D.J. Bolton Abstract Aims: The aims of this research were (1) to determine the occurrence of Salmonella in Irish restaurant kitchens and (2) to investigate the serovar, genotype, antibiotic resistance profile and survival/growth profile of the Salmonella under catering chilled storage and temperature abuse conditions. Methods: Five sites/tools in each of 200 randomly selected restaurant kitchens were examined for the presence of presumptive Salmonella spp. by enrichment. Serotyping, antibiotic resistance studies and genotyping were performed using the Kauffmann-White, CLSI and PulseNet methods, respectively. Survival/growth was investigated in milk, meat and vegetable products. Results: Presumptive isolates from 15 of the 200 restaurant kitchens were recovered and confirmed as Salmonella positive. Seven different serovars showing a variety of antibiotic resistance profiles were detected. PFGE profiles suggested that isolates from geographically adjacent restaurants were related. Salmonella survived in foods stored at typical catering refrigeration temperatures and increased by approximately 0·8 log10 CFU ml,1 per day in food products stored under conditions of thermal abuse (20°C). Conclusions: Inadequate hygiene has resulted in contamination of restaurant kitchens with Salmonella, which may persist/multiply in cross-contaminated foods. Significance and Impact of the Study: This study highlights the need for greater hygiene in restaurant kitchens coupled with rapid chilling of food not for immediate consumption and reheating before subsequent serving. [source] Premature Salmonella Typhimurium growth inhibition in competition with other Gram-negative organisms is redox potential regulated via RpoS inductionJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2004E. Komitopoulou Abstract Aims:, To identify the role of oxidation,reduction (redox) potential in the premature growth inhibition and RpoS induction in Salmonella serotype Typhimurium in competitive growth experiments. Methods and Results:, Oxidation,reduction potential was measured throughout the growth of a minority population of Salm. Typhimurium in mixed cultures with other Gram-negative and Gram-positive organisms. A lux -based reporter was also used to evaluate RpoS activity in Salm. Typhimurium in competitor studies. In a mixed culture, the multiplication of a minority population of Salm. Typhimurium was inhibited when competing Gram-negative organisms entered the stationary phase. This was not seen when the competing flora was Gram-positive. The change in redox potential during growth in mixed cultures was closely linked to the inhibition of Salm. Typhimurium growth by Gram-negative competitors. An artificially induced drop in redox potential earlier during growth in mixed cultures with Gram-negative organisms reduced the time to RpoS induction in Salm. Typhimurium and thus inhibited its multiplication prematurely. In contrast, RpoS induction and growth inhibition were prevented under high redox potential conditions. Conclusions:, This work shows that the inhibitory activity of competitive organisms can be mediated through their effect on redox potential-regulated RpoS induction. Significance and Impact of the Study:, Redox potential is shown to be an important determinant of Salm. Typhimurium growth, an observation with practical implications both for its control and detection. [source] Scaling and Testing Multiplicative Combinations in the Expectancy,Value Model of AttitudesJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 9 2008Icek Ajzen This article examines the multiplicative combination of belief strength by outcome evaluation in the expectancy,value model of attitudes. Because linear transformation of a belief strength measure results in a nonlinear transformation of its product with outcome evaluation, use of unipolar or bipolar scoring must be empirically justified. Also, the claim that the Belief × Evaluation product fails to explain significant variance in attitudes is found to be baseless. In regression analyses, the main effect of belief strength takes account of the outcome's valence, and the main effect of outcome evaluation incorporates the outcome's perceived likelihood. Simulated data showed that multiplication adds substantially to the prediction of attitudes only when belief and evaluation measures cover the full range of potential scores. [source] Production of gliotoxin on natural substrates by Trichoderma virensJOURNAL OF BASIC MICROBIOLOGY, Issue 1 2005R. Anitha Dr. Gliotoxin, an epithiodiketopiperazine toxin produced by the ,Q' strain of Trichoderma virens is essential for curtailing growth and multiplication of phytopathogens (Howellet al. 1993, Fravel 1988). Three isolates (Gv, Gv-A and Gv-V) of Trichoderma virens were grown on natural substrates such as bengal gram hull, gingelly cake, green gram hull, rice bran, soya meal, sugarcane bagasse, soyameal + tapioca, tapioca powder, tapioca peel and wheat bran). It was evident from this study that maximum gliotoxin (64 mg/l) was produced on tapioca powder by the alien isolate Gv. However sugarcane bagasse significantly enhanced gliotoxin production (36 mg/l) in the native isolate Gv-A, when compared to other substrates like greengram hull and rice bran. So far, studies on production of gliotoxin on synthetic media has been reported. We report the production of gliotoxin by T. virens on natural substrates "in vitro" for the first time. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Generalization of multivariate optical computations as a method for improving the speed and precision of spectroscopic analysesJOURNAL OF CHEMOMETRICS, Issue 6 2008Marc K. Boysworth Abstract Multivariate optical computations (MOCs) offer improved analytical precision and increased speed of analysis via synchronous data collection and numerical computation with scanning spectroscopic systems. The improved precision originates in the redistribution of integration time from spurious channels to informative channels in an optimal manner for increasing the signal-to-noise ratio with multivariate analysis under the constraint of constant total analysis time. In this work, MOCs perform the multiplication and addition steps of spectral processing by adjusting the integration parameters of the optical detector or adjusting the scanning profile of the tunable optical filter. Improvement in the precision of analysis is achieved via the implicit optimization of the analytically useful signal-to-noise ratio. The speed improvements are realized through simpler data post-processing, which reduces the computation time required after data collection. Alternatively, the analysis time may be significantly truncated while still seeing an improvement in the precision of analysis, relative to competing methods. Surface plasmon resonance (SPR) spectroscopic sensors and visible reflectance spectroscopic imaging were used as test beds for assessing the performance of MOCs. MOCs were shown to reduce the standard deviation of prediction by 15% compared to digital data collection and analysis with the SPR and up to 45% for the imaging applications. Similarly, a 30% decrease in the total analysis time was realized while still seeing precision improvements. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||