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Kinds of Work Shows Selected AbstractsSORTAL ANAPHORA RESOLUTION IN MEDLINE ABSTRACTSCOMPUTATIONAL INTELLIGENCE, Issue 1 2007Manabu Torii This paper reports our investigation of machine learning methods applied to anaphora resolution for biology texts, particularly paper abstracts. Our primary concern is the investigation of features and their combinations for effective anaphora resolution. In this paper, we focus on the resolution of demonstrative phrases and definite determiner phrases, the two most prevalent forms of anaphoric expressions that we find in biology research articles. Different resolution models are developed for demonstrative and definite determiner phrases. Our work shows that models may be optimized differently for each of the phrase types. Also, because a significant number of definite determiner phrases are not anaphoric, we induce a model to detect anaphoricity, i.e., a model that classifies phrases as either anaphoric or nonanaphoric. We propose several novel features that we call highlighting features, and consider their utility particularly for processing paper abstracts. The system using the highlighting features achieved accuracies of 78% and 71% for demonstrative phrases and definite determiner phrases, respectively. The use of the highlighting features reduced the error rate by about 10%. [source] Screening for Asymptomatic Left Ventricular Dysfunction Using B-Type Natriuretic PeptideCONGESTIVE HEART FAILURE, Issue 2008Theresa A. McDonagh MD Asymptomatic left ventricular dysfunction (ASLVD), a known precursor phase of heart failure, fulfills the essential criteria that should be met before screening for a disease. It is common and associated with reduced longevity and quality of life. Left untreated, it progresses to heart failure, which incurs a mortality greater than most cancers as well as significant morbidity rates. In addition, we now have several population-based studies that demonstrate that both B-type natriuretic peptide (BNP) and N-terminal prohormone brain natriuretic peptide (NTproBNP) can accurately exclude left ventricular systolic dysfunction. More recent work shows that this can be done cost-effectively. There is also a wealth of evidence from randomized controlled trials indicating that the treatment of ASLVD can reduce both morbidity and mortality and slow progression to the heart failure state. The main stumbling block to implementation of screening, in addition to the perceived cost, may well be the lack of a randomized study showing that screening the population for ASLVD really does alter the natural history of the condition, something that other screening strategies have so far failed to do. Congest Heart Fail. 2008;14(4 suppl 1):5,8. ©2008 Le Jacq [source] Fly Six-type homeodomain proteins Sine oculis and Optix partner with different cofactors during eye developmentDEVELOPMENTAL DYNAMICS, Issue 3 2005Kristy L. Kenyon Abstract Two members from the Six class of homeobox transcription factors, Sine oculis (SO) and Optix, function during development of the fly visual system. Differences in gain-of-function phenotypes and gene expression suggest that these related factors play distinct roles in the formation of the fly eye. However, the molecular nature of their functional differences remains unclear. In this study, we report the identification of two novel factors that participate in specific partnerships with Sine oculis and Optix during photoreceptor neurons formation and in eye progenitor cells. This work shows that different cofactors likely mediate unique functions of Sine oculis and Optix during the development of the fly eye and that the repeated requirement for SO function at multiple stages of eye development reflects the activity of different SO,cofactor complexes. Developmental Dynamics 234:497,504, 2005. © 2005 Wiley-Liss, Inc. [source] Electrochemical Investigation of the Role of Reducing Agents in Copper-Catalyzed Nitric Oxide Release from S-NitrosoglutathioneELECTROANALYSIS, Issue 18 2006Monique David-Dufilho Abstract Studies of nitric oxide (NO) release from S -nitrosoglutathione (GSNO) decomposition by Cu2+ in the presence of reducing agents were performed using a nickel porphyrin and Nafion-coated microsensor in order to compare the efficiency of sodium hydrosulfite (Na2S2O4) and sodium borohydride (NaBH4) to that of the most abundant endogenous reducer, glutathione (GSH). When it was mixed to Cu(NO3)2 and added to equimolar concentration of GSNO, each reducing agent caused a NO release (measured in terms of oxidation current) but only NaBH4 induced a proportional rise if its concentration doubled and that of Cu2+ remained constant. For Na2S2O4, there was a mild increase and for GSH, no change. Furthermore, when Cu2+ concentrations ranging from 0.5 to 5,,M were mixed with 2,,M reducing agent and added to 2,,M GSNO, the NO oxidation current linearly increased with NaBH4 and was constant with Na2S2O4. Concerning GSH, Cu2+ dose-dependently increased the NO release from GSNO only if the Cu2+ -to-reducer ratio was ,1. However, GSH formed the catalytic species Cu+ even in excess of Cu2+ and GSNO as indicated by suppression of the Cu2+/GSH-induced NO release when the Cu+ chelator neocuproine was added to GSNO. This work shows that, among the 3 reducing agents, only NaBH4 allows Cu2+ to dose-dependently increase the NO release from GSNO for Cu2+ -to-reducer ratios ranging from 0.25 to 2.5. Despite this good effectiveness, excess of NaBH4 compared to both Cu2+ and GSNO seems to be required for optimal NO release. [source] A three-dimensional model of the U1 small nuclear ribonucleoprotein particleENTOMOLOGICAL RESEARCH, Issue 2 2010Jason A. SOMARELLI Abstract Most of the pre-mRNAs in the eukaryotic cell are comprised of protein-coding exons and non-protein-coding introns. The introns are removed and the exons are ligated together, or spliced, by a large, macromolecular complex known as the spliceosome. This RNA-protein assembly is made up of five uridine-rich small nuclear RNAs (U1-, U2-, U4-, U5- and U6-snRNA) as well over 300 proteins, which form small nuclear ribonucleoprotein particles (snRNPs). Initial recognition of the 5, exon/intron splice site is mediated by the U1 snRNP, which is composed of the U1 snRNA as well as at least ten proteins. By combining structural informatics tools with the available biochemical and crystallographic data, we attempted to simulate a complete, three dimensional U1 snRNP from the silk moth, Bombyx mori. Comparison of our model with empirically derived crystal structures and electron micrographs pinpoints both the strengths and weaknesses in the in silico determination of macromolecular complexes. One of the most striking differences between our model and experimentally generated structures is in the positioning of the U1 snRNA stem-loops. This highlights the continuing difficulties in generating reliable, complex RNA structures; however, three-dimensional modeling of individual protein subunits by threading provided models of biological significance and the use of both automated and manual docking strategies generated a complex that closely reflects the assembly found in nature. Yet, without utilizing experimentally-derived contacts to select the most likely docking scenario, ab initio docking would fall short of providing a reliable model. Our work shows that the combination of experimental data with structural informatics tools can result in generation of near-native macromolecular complexes. [source] Adoptive transfer of an anti-MART-127,35 -specific CD8+ T,cell clone leads to immunoselection of human melanoma antigen-loss variants in SCID miceEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 2 2003Francesco Lozupone Abstract The identification of appropriate mouse models could be useful in carefully evaluating the actual role of the in vivo development of antigen-loss variants during antigen-specific vaccine therapy of human tumors. In this study we investigated the level of efficacy of a MART-1/Melan-A-specific CD8+ T,cell clone against its autologous melanoma in a severe combined immunodeficiency (SCID) mouse model, in which the tumor cells expressed in vivo heterogeneous and suboptimal levels of MART-1. The subcutaneous co-injection of the MART-1/Melan-A-reactive T,cell clone A42 with MART-1/Melan-A+ autologous human melanoma cells into SCID mice caused a total inhibition of tumor growth. However, the systemic treatment with A42 clone lymphocytes resulted inonly 50,60% inhibition of tumor growth, although the T,cell clone targeted the tumors and the MART-1+ cells virtually disappeared from the tumors. This study suggests that an immunotherapybased on the expansion of an antigen-specific T,cell clone generated in vitro is highly efficient in abolishing tumor growth when the target antigen is fully expressed, but leads to in vivoimmunoselection of antigen-loss variants in the presence of suboptimal levels of antigen expression. Furthermore, this work shows that human tumors/SCID mouse models may be useful in evaluating thein vivo efficacy of adoptive immunotherapies. [source] Controllable Synthesis of Cu2O Microcrystals via a Complexant-Assisted Synthetic RouteEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2010Wanqun Zhang Abstract A novel method using Cu(AC)2·H2O and dimethylglyoxime as reagents has been successfully developed for the controllable synthesis of Cu2O microcrystals with distinctive morphologies, including porous hollow microspheres, octahedral microcages, and microcrystals with truncated corners and edges and octahedral microcrystals. These structures can be fine-tuned by varying reaction temperature, reaction time, and concentration. The products were characterized by X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectra, and UV/Vis diffuse reflectance spectra. This is the first report of the preparation of the novel microcage structure of Cu2O through a simple solution-based route. By investigating the intermediate products which resemble the final crystal structures, a possible growth mechanism is proposed. Moreover, the investigations showed that the various 3D architectures of the as-made products exhibit different abilities to catalytically degrade rhodamine-B. Our work shows that octahedral Cu2O crystals with entirely {111} faces are photocatalytically more active than octahedral microcrystals with truncated corners and edges, suggesting the {111} faces of Cu2O nanostructures are catalytically more active than the {100} and {110} faces. Due to dual effect of the cavity structure and the {111} surfaces, the octahedral microcages with truncated corners and edges exhibit a higher extent of the photodecomposition reaction. As a result of very slow photocorrosion rate of the Cu2O microcrystal, it is expected that these microcrystals with different surfaces may find more applications in photocatalysis. [source] Large aggregating and small leucine-rich proteoglycans are degraded by different pathways and at different rates in tendonFEBS JOURNAL, Issue 17 2004Tom Samiric This work investigated the kinetics of catabolism and the catabolic fate of the newly synthesized 35S-labelled proteoglycans present in explant cultures of tendon. Tissue from the proximal region of bovine deep flexor tendon was incubated with [35S]sulfate for 6 h and then placed in explant cultures for periods of up to 15 days. The amount of radiolabel associated with proteoglycans and free [35S]sulfate lost to the medium and retained in the matrix was determined for each day in culture. It was shown that the rate of catabolism of radiolabelled small proteoglycans (decorin and biglycan) was significantly slower (T½ > 20 days) compared with the radiolabelled large proteoglycans (aggrecan and versican) that were rapidly lost from the tissue (T½ , 2 days). Both the small and large newly synthesized proteoglycans were lost from the matrix with either intact or proteolytically modified core proteins. When explant cultures of tendon were maintained either at 4 °C or in the presence of the lysosomotrophic agent ammonium chloride, inhibition of the cellular catabolic pathway for small proteoglycans was demonstrated indicating the involvement of cellular activity and lysosomes in the catabolism of small proteoglycans. It was estimated from these studies that approximately 60% of the radiolabelled small proteoglycans that were lost from the tissue were degraded by the intracellular pathway present in tendon cells. This work shows that the pathways of catabolism for large aggregating and small leucine-rich proteoglycans are different in tendon and this may reflect the roles that these two populations of proteoglycans play in the maintenance of the extracellular matrix of tendon. [source] Environmental and developmental controls on specific leaf area are little modified by leaf allometryFUNCTIONAL ECOLOGY, Issue 4 2008R. Milla Summary 1Recent work shows that large leaves tend to require higher biomass investments per unit leaf area than small leaves. As a consequence, specific leaf area (SLA), which is a focus trait for a bulk of physiological and ecological research programs, is dependent on leaf size variation. Here, we address whether size dependency alters the outcome of research dealing with SLA responses to environmental or developmental change. 2We compiled lamina mass (M) and surface area (A) data for 2158 leaves of 26 species, coming from studies investigating the reaction of SLA to variation in rainfall, growth,season length, light intensity, atmospheric CO2, fire frequency, type of branch and leaf and plant age. We fitted the function M = a Ab to the data of each experimental situation separately, and implemented a method to split SLA response as measured in the original study (SLADm) into response due to leaf size dependency (SLADa), and response due to treatment effects, after controlling for leaf size dependency (SLADt). 3The sign of the reaction did not differ between SLADm and SLADt. However, the magnitude of that response changed for most contrasts, though in variable ways. 4Conclusions of past experiments hold, for the most part, after re-analysis including size dependency. However, given the large heterogeneity found here, we advise that future work investigating SLA be prepared to account for leaf size dependency when the factors under focus are suspected to alter leaf size. [source] Granzyme B: a natural born killerIMMUNOLOGICAL REVIEWS, Issue 1 2003Sarah J. Lord Summary:, A main pathway used by cytotoxic T lymphocytes (CTLs) and natural killer cells to eliminate pathogenic cells is via exocytosis of granule components in the direction of the target cell, delivering a lethal hit of cytolytic molecules. Amongst these, granzyme B and perforin have been shown to induce CTL-mediated target cell DNA fragmentation and apoptosis. Once released from the CTL, granzyme B binds its receptor, the mannose-6-phosphate/insulin-like growth factor II receptor, and is endocytosed but remains arrested in endocytic vesicles until released by perforin. Once in the cytosol, granzyme B targets caspase-3 directly or indirectly through the mitochondria, initiating the caspase cascade to DNA fragmentation and apoptosis. Caspase activity is required for apoptosis to occur; however, in the absence of caspase activity, granzyme B can still initiate mitochondrial events via the cleavage of Bid. Recent work shows that granzyme B-mediated release of apoptotic factors from the mitochondria is essential for the full activation of caspase-3. Thus, granzyme B acts at multiple points to initiate the death of the offending cell. Studies of the granzyme B death receptor and internal signaling pathways may lead to critical advances in cell transplantation and cancer therapy. [source] Defective Toll-like receptor 9-mediated cytokine production in B cells from Bruton's tyrosine kinase-deficient miceIMMUNOLOGY, Issue 2 2008Maroof Hasan Summary Bruton's tyrosine kinase (Btk), a member of the Tec family of tyrosine kinases, plays an important role in the differentiation and activation of B cells. Mutations affecting Btk cause immunodeficiency in both humans and mice. In this study we set out to investigate the potential role of Btk in Toll-like receptor 9 (TLR9) activation and the production of pro-inflammatory cytokines such as interleukin (IL)-6, tumour necrosis factor (TNF)-, and IL-12p40. Our data show that Btk-deficient B cells respond more efficiently to CpG-DNA stimulation, producing significantly higher levels of pro-inflammatory cytokines but lower levels of the inhibitory cytokine IL-10. The quantitative reverse transcription,polymerase chain reaction (RT-PCR) analysis presented in this work shows that mRNA production of one of the important new members of the IL-12 family, IL-27, was significantly increased in Btk-deficient B cells after CpG-DNA stimulation. In this study, we demonstrate significant differences in CpG responsiveness between transitional 1 (T1) and T2 B cells for survival and maturation. Furthermore, TLR9 expression, measured both as protein and as mRNA, was increased in Btk-defective cells, especially after TLR9 stimulation. Collectively, these data provide evidence in support of the theory that Btk regulates both TLR9 activation and expression in mouse splenic B cells. [source] Friction term discretization and limitation to preserve stability and conservation in the 1D shallow-water model: Application to unsteady irrigation and river flowINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 4 2008J. Burguete Abstract Friction is one of the relevant forces included in the momentum equation of the 1D shallow-water model. This work shows that a pointwise discretization of the friction term unbalances this term with the rest of the terms in the equation in steady state. On the other hand, an upwind discretization of the friction term ensures the correct discrete balance. Furthermore, a conservative technique based on the limitation of the friction value is proposed in order to avoid unbounded values of the friction term in unsteady cases of advancing front over dry and rough surfaces. This limitation improves the quality of unsteady solutions in wet/dry fronts and guarantees the numerical stability in cases with dominant friction terms. The proposed discretization is validated in some test cases with analytical solution or with measured data and used in some practical cases. Copyright © 2007 John Wiley & Sons, Ltd. [source] Biofunctionalized pH-Responsive Microgels for Cancer Cell Targeting: Rational Design,ADVANCED MATERIALS, Issue 1 2006M. Das The design of a drug-delivery system based on bioconjugated, pH-responsive microgels is demonstrated. Microgels loaded with the anticancer drug Doxorubicin are introduced into the HeLa tumor cells by means of receptor- mediated endocytosis. Changes in pH within the intracellular environment induce shrinkage of microgels, triggering the drug release into the cells. The microgel described in this work shows enhanced cytotoxicity to HeLa cells (see Figure). [source] Implications of seasonal and diurnal variations of wind velocity for power output estimation of a turbine: a case study of GrenadaINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 13 2003D. Weisser Abstract This case study highlights the importance of taking into consideration diurnal variations of wind velocity for wind energy resources assessment. Previous studies of wind energy distribution that are based on the two-parameter Weibull density function have so far neglected to consider time of day fluctuations in wind speed, instead concentrating primarily on seasonal deviations. However, this has serious implications where such a wind energy model is the underpinning of calculations for the potential power production from a wind turbine and in particular where the timing of the energy output is essential to meet electricity loads. In the case of Grenada the energy output from a wind turbine during the day is approximately two times the output at night thereby fluctuating enormously around the seasonal mean distribution. When this is not taken into account the economic and technological viability of a wind turbine project may be overestimated or not even be identified. This work shows how a wind energy resources assessment based on the Weibull distribution model can be done and how the power output of a horizontal axis turbine is calculated. An analysis of the recorded wind data confirms the application of the Weibull density function as a suitable tool for modelling wind regimes. Copyright © 2003 John Wiley & Sons, Ltd. [source] Median-based aggregation operators for prototype construction in ordinal scalesINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 6 2003Josep Domingo-Ferrer This article studies aggregation operators in ordinal scales for their application to clustering (more specifically, to microaggregation for statistical disclosure risk). In particular, we consider these operators in the process of prototype construction. This study analyzes main aggregation operators for ordinal scales [plurality rule, medians, Sugeno integrals (SI), and ordinal weighted means (OWM), among others] and shows the difficulties for their application in this particular setting. Then, we propose two approaches to solve the drawbacks and we study their properties. Special emphasis is given to the study of monotonicity because the operator is proven nonsatisfactory for this property. Exhaustive empirical work shows that in most practical situations, this cannot be considered a problem. © 2003 Wiley Periodicals, Inc. [source] Pathways that produce volatile sulphur compounds from methionine in Oenococcus oeniJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2008A. Vallet Abstract Aims:, Determination of pathways involved in synthesis of volatile sulphur compounds (VSC) from methionine by Oenococcus oeni isolated from wine. Methods and Results:, Production of VSC by O. oeni from methionine was investigated during bacterial cultures and in assays performed in the presence of resting cells or protein fractions. Cells of O. oeni grown in a medium supplemented with methionine produced methanethiol, dimethyl disulphide, methionol and 3-(methylthio)propionic acid. Methional was also detected, but only transiently during the exponential growth phase. It was converted to methionol and 3-(methylthio) propionic acid in assays. Although this acid could be produced alternatively from 2-oxo-4-(methylthio) butyric acid (KMBA) by oxidative decarboxylation. In addition, KMBA was a precursor for methanethiol and dimethyl disulphide synthesis. Interestingly, assays with resting cells and protein fractions suggested that a specific enzyme could be involved in this conversion in O. oeni. Conclusion:, This work shows that methional and KMBA are the key intermediates for VSC synthesis from methionine in O. oeni. Putative enzymatic and chemical pathways responsible for the production of these VSC are discussed. Significance and impact of the study:, This work confirms the capacity of O. oeni to metabolize methionine and describes the involvement of potential enzymatic pathways. [source] Characterization of extracellular polymers synthesized by tropical intertidal biofilm bacteriaJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2007B.O. Ortega-Morales Abstract Aim:, This study was performed to determine the potential of tropical intertidal biofilm bacteria as a source of novel exopolymers (EPS). Methods and Results:, A screening procedure was implemented to detect EPS-producing biofilm bacteria. Isolates MC3B-10 and MC6B-22, identified respectively as a Microbacterium species and Bacillus species by 16S rDNA and cellular fatty acids analyses, produced different EPS, as evidenced by colorimetric and gas chromatographic analyses. The polymer produced by isolate MC3B-10 displays significant surfactant activity, and may chelate calcium as evidenced by spectroscopic analysis. Conclusions:, Polymer MC3B-10 appears to be a glycoprotein, while EPS MC6B-22 seems to be a true polysaccharide dominated by neutral sugars but with significant concentrations of uronic acids and hexosamines. EPS MC3B-10 possesses a higher surfactant activity than that of commercial surfactants, and given its anionic nature, may chelate cations thus proving useful in bioremediation. The chemical composition of polymer MC6B-22 suggests its potential biomedical application in tissue regeneration. Significance and Impact of the Study:, This is the first report of a Microbacterium species producing EPS with surfactant properties, which expands our knowledge of the micro-organisms capable of producing these biomolecules. Furthermore, this work shows that tropical intertidal environments are a nonpreviously recognized habitat for bioprospecting EPS-producing bacteria, and that these molecules might be involved in ecological roles protecting the cells against dessication. [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] Effect of the origin of ZnO nanoparticles dispersed in polyimide films on their photoluminescence and thermal stabilityJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2008Anongnat Somwangthanaroj Abstract Polyimide (PI) films containing dispersed ZnO nanoparticles were prepared from both zinc nitrate hexahydrate (designated as Zn(NO3)2/PI) and ZnO nanoparticles, 2-nm average primary size (ZnO/PI). This work shows how the origin of ZnO affects both the photoluminescence and thermal decomposition of the film. The presence of ZnO derived from Zn(NO3)2·6H2O was confirmed by X-ray diffraction technique. The fluorescent intensities from Zn(NO3)2/PI and ZnO/PI were much higher than that from pure PI films. When the ZnO concentration exceeded a certain saturation level, the emission intensity decreased due to the undesirable aggregation of ZnO. At the same concentration, ZnO/PI exhibited higher emission intensity than Zn(NO3)2/PI. All samples prepared under nitrogen emitted higher intensity than their counterparts prepared under argon. The ZnO/PI film was thermally more stable than the Zn(NO3)2/PI one. From TEM images of 117.6 mol% ZnO/PI films, the ZnO aggregates, whose average size was 17,90 nm, were well distributed throughout the film but poorly dispersed in nanometer range. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] The transient nature of maximum maleic anhydride grafting of polypropylene: A mechanistic approach based on a consecutive reaction model.JOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007Abstract This article compares the batch solution and molten state chemical modification of an atactic polypropylene to yield a grafted polypropylene. Short reaction times appear to be sufficient and indeed necessary for the highest graft yields to be obtained if degradative processes occurring in both reaction media are to be avoided. The consecutive reactions for the optimized grafting reaction pathway were proposed for the solution process in an earlier article. The present work attempts to correlate this pathway with that of the molten state process. Grafted succinic anhydride groups react with two resorcine molecules to yield grafted succinyl-fluorescein groups. This work considers the resorcine units as true molecular probes, to be able to stabilize and activate the complexes formed between the succinic anhydride groups and the propylene sequence. This work shows the unsteady and later dynamic character of the process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 345,351, 2007 [source] Institutions for Financial Development: What are they and where do they come from?JOURNAL OF ECONOMIC SURVEYS, Issue 1 2006Leopoldo Fergusson Abstract., Among the fundamental causes of long-run economic performance, differences in ,institutions' have received considerable attention in recent years. At the same time, a large body of theoretical and empirical work shows that financial development can have a big effect on economic performance. This raises the more fundamental question as to why some countries have developed financial markets while others do not. This paper reviews the theoretical and empirical research on this issue and shows that one of the channels whereby better institutions may have an effect on economic development is through the consolidation of larger and better financial markets. An issue that is left aside in this paper relates to what regulations and policies lead to better functioning capital markets. At some level, one can think of regulations and policies as particular types of institutions. Nonetheless, institutional problems are deeper causes leading to poor economic performance; bad policies might simply be part of the channels through which they influence performance. Thus, addressing the question of what determines the emergence of ,good' institutions , i.e. institutions that promote financial development , seems particularly important. Recent research providing some answers to this question is also reviewed. [source] Neural network-based state prediction for strategy planning of an air hockey robotJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 4 2001Jung Il Park We analyze a neural network implementation for puck state prediction in robotic air hockey. Unlike previous prediction schemes which used simple dynamic models and continuously updated an intercept state estimate, the neural network predictor uses a complex function, computed with data acquired from various puck trajectories, and makes a single, timely estimate of the final intercept state. Theoretically, the network can account for the complete dynamics of the table if all important state parameters are included as inputs, an accurate data training set of trajectories is used, and the network has an adequate number of internal nodes. To develop our neural networks, we acquired data from 1500 no-bounce and 1500 one-bounce puck trajectories, noting only translational state information. Analysis showed that performance of neural networks designed to predict the results of no-bounce trajectories was better than the performance of neural networks designed for one-bounce trajectories. Since our neural network input parameters did not include rotational puck estimates and recent work shows the importance of spin in impact analysis, we infer that adding a spin input to the neural network will increase the effectiveness of state estimates for the one-bounce case. © 2001 John Wiley & Sons, Inc. [source] EFFECT OF WATER ACTIVITY ON PHYSICAL PROPERTIES OF CONJUGATED LINOLEIC ACID (CLA) MICROCAPSULESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2010MARIBEL JIMENEZ ABSTRACT The physical properties of spray drying powders must be considered for the design of equipment. Conjugated linoleic acid (CLA) microcapsules were spray dried by using the following as wall materials: whey protein concentrate (WPC), a blend of whey protein concentrate,maltodextrins (WPC-MD) and gum arabic (GA). These were prepared and their physical properties were studied. The bulk density, packed density, particle density, compressibility and color of the microcapsules were evaluated in a range of water activities from 0.108 to 0.898. No significant differences in the physical properties were found when WPC was used as a wall material in the microcapsules stored at the whole range of water activities tested. Maltodextrins conferred changes in some of the physical properties of the microcapsules (WPC-MD) upon storage at high water activities. GA microcapsules showed drastic changes in all physical properties studied at water activities above 0.628. PRACTICAL APPLICATIONS This work shows the best conditions for storing conjugated linoleic acid (CLA) microcapsules elaborated with different wall materials, which have been reported to have a high potential as a food additive because of the nutraceutical properties of CLA. This research should reveal the behavior of water activity during storage on physical properties, and make it possible to predict what characteristics need to be added to a food, besides being important for the design of equipment, packing and transport. [source] EFFECT OF HIGH-PRESSURE PROCESSING ON TEXTURE AND DRYING BEHAVIOR OF PINEAPPLEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2009A.R.P. KINGSLY ABSTRACT The effect of high-pressure processing on texture and drying behavior of pineapple slices was investigated. Pineapple slices were high pressure processed at 50, 100, 300, 500 and 700 MPa at 25C for 10 min. The control, hot water-blanched and high-pressure processed samples were then dehydrated at 70C. Application of high pressure reduced the sample hardness, springiness and chewiness while it had no significant effect on cohesiveness of pineapple. Elevated pressure treatment (,500 MPa) reduced drying time more effectively than for the other pretreated samples. Experimental dehydration data were empirically fitted using six thin-layer drying models. Among the models tested, logarithmic model best described the drying behavior of pineapple slices. The effective moisture diffusivity was found to increase with an increase in the level of pressure up to 500 MPa, and the samples processed at 500 and 700 MPa had higher diffusivity values than blanched samples. PRACTICAL APPLICATIONS This work shows that high-pressure blanching of pineapple can be an alternative for hot water blanching, before dehydration. The results may find application in development of quality snack food from pineapple fruits. [source] EFFECT OF OSMOTIC TREATMENT WITH CONCENTRATED SUGAR AND SALT SOLUTIONS ON KINETICS AND COLOR IN VACUUM CONTACT DRYINGJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2007S.M.A. RAHMAN ABSTRACT An experimental study of osmotic dehydration (OD) of selected heat-sensitive products was carried out in a laboratory-scale vacuum contact dryer. Cubes of potato and apple were examined as model heat-sensitive objects. Experiments were conducted at different conduction heat input levels with wall temperatures in the range 35,45C under vacuum and also in pure vacuum without any external heat input. Detailed investigations were carried out of OD on drying performance, product temperature and color of the dried product. PRACTICAL APPLICATIONS Osmotic treatment of potato and apple samples using concentrated sugar solution shows better osmotic dehydration as well as drying rate in a vacuum contact drying system. This information may help to select the osmotic agent in any industrial application for faster drying rate in vacuum contact drying specially for food products. Moreover this work shows the analysis to find out the starting point of precipitation of osmotic agent inside the products in terms of drying time, temperature and moisture content. This information will be helpful for critical analysis in osmotic dehydration technique which in turns may help for optimum design. [source] Stabilization and Partial Purification of a Protease from Ginger Rhizome (Zingiber offinale Roscoe)JOURNAL OF FOOD SCIENCE, Issue 3 2005Pitaya Adulyatham ABSTRACT: Ginger protease (GP) or zingibain is of interest as a meat tenderizing agent. The objective of this research was to investigate food-compatible methods for stabilizing GP during storage or enzyme fractionation. Crude GP extracted from fresh ginger had a half-life (t1/2) of 2.1 (±0.16) d at 5°C decreasing to 20 min at 30°C. Addition of ascorbate (0.2% w/v) increased the t1/2 for GP from 2 to 20 d at 5°C. Dithiothreitol or Ethylenediaminetetraacetic acid (EDTA) had no effect on GP stability. Acetone powder preparations from ginger yielded GP with t1/2 of 18 mo at 5°C. Crude GP extracted from acetone powder was sufficiently stabilized to allow fractionation by ion exchange chromatography without the addition of toxic or expensive additives. GP was partially purified 252-fold with a recovery of 61%. The nomimal molecular weight of GP was 34.8 kDa compared with 25.1 kDa for papain. This work shows that the stability of GP can be greatly improved, increasing its attractiveness as a commercial product. Some possible routes of GP deactivation and stabilization are discussed. [source] Blood Cyanide Determination in Two Cases of Fatal Intoxication: Comparison Between Headspace Gas Chromatography and a Spectrophotometric Method*JOURNAL OF FORENSIC SCIENCES, Issue 6 2007Veniero Gambaro M.Sc. Abstract:, Blood samples of two cases were analyzed preliminarily by a classical spectrophotometric method (VIS) and by an automated headspace gas chromatographic method with nitrogen-phosphorus detector (HS-GC/NPD). In the former, hydrogen cyanide (HCN) was quantitatively determined by measuring the absorbance of chromophores forming as a result of interaction with chloramine T. In the automated HS-GC/NPD method, blood was placed in a headspace vial, internal standard (acetonitrile) and acetic acid were then added. This resulted in cyanide being liberated as HCN. The spectrophotometric (VIS) and HS-GC/NPD methods were validated on postmortem blood samples fortified with potassium cyanide in the ranges 0.5,10 and 0.05,5 ,g/mL, respectively. Detection limits were 0.2 ,g/mL for VIS and 0.05 ,g/mL for HS-GC/NPD. This work shows that results obtained by means of the two procedures were insignificantly different and that they compared favorably. They are suitable for rapid diagnosis of cyanide in postmortem cases. [source] Synthesis of 3H and fluorescence-labelled poly (DL -Lactic acid)JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 10 2001S. Ponsart Abstract The novel polymer modification method based on the activation of an aliphatic polyester chain by using lithium diisopropylamide at low temperature to form a polycarbanion bearing nucleophilic sites in a position , to the carbonyl groups was applied to rac -poly (lactic acid), PLA50, to label this polymer with radioactive tritium atoms or with a fluorescent dye. Despite simultaneous partial chain degradation, radioactive PLA50 and fluorescent PLA50 with Mn=14000 g mol,1, Mw/Mn=1.9 and Mn=32 000 g mol,1, Mw/Mn=2.4, respectively, were obtained. The specific activity of the final compound was 3.7 µCi g,1 that squared with 0.3, substitution reaction. The fluorescent polymer was substituted with 0.25% ratio. This work shows that the LDA activation method appears to have considerable potential. Copyright © 2001 John Wiley & Sons, Ltd. [source] Binding site on human immunoglobulin G for the affinity ligand HWRGWVJOURNAL OF MOLECULAR RECOGNITION, Issue 3 2010Haiou Yang Abstract Affinity ligand HWRGWV has demonstrated the ability to isolate human immunoglobulin G (hIgG) from mammalian cell culture media. The ligand specifically binds hIgG through its Fc portion. This work shows that deglycosylation of hIgG has no influence on its binding to the HWRGWV ligand and the ligand does not compete with Protein A or Protein G in binding hIgG. It is suggested by the mass spectrometry (MS) data and docking simulation that HWRGWV binds to the pFc portion of hIgG and interacts with the amino acids in the loop Ser383,Asn389 (SNGQPEN) located in the CH3 domain. Subsequent modeling has suggested a possible three-dimensional minimized solution structure for the interaction of hIgG and the HWRGWV ligand. The results support the fact that a peptide as small as a hexamer can have specific interactions with large proteins such as hIgG. Copyright © 2009 John Wiley & Sons, Ltd. [source] Solid-state properties of warfarin sodium 2-propanol solvateJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2004Agam R. Sheth Abstract The goal of the present work was to understand the effect of relative humidity (RH) and temperature on the molecular structure, crystal structure, and physical properties of warfarin sodium 2-propanol solvate (W). After previous determination of the crystal structure of W, which corresponds to a 1:1 2-propanol solvate, the present work shows that W has a critical RH (60%,<,RH0,,,68%), below which minimal uptake of water occurs, due to surface adsorption, but above which gradual and continuous uptake of water occurs, due to deliquescence. Deliquescence begins at the surface and proceeds inward into the bulk of the crystal. Single crystal X-ray diffractometry indicates no change in the crystal and molecular structure of W during the initial stages of deliquescence. Studies of the unit cell and volume computations of W show that water can neither find space to enter the crystal lattice, nor can replace 2-propanol. Thus, water does not exchange with 2-propanol within the lattice, contrary to previous reports. Storage of single crystals of W at 120°C for 23 h produces shrinkage cracks along the needle (b) axis, which are interpreted as a reduction in d -spacing of the 00l planes. Thus, under thermal stress, W crystals undergo amorphization with concurrent loss of 2-propanol, which may proceed via an intermediate crystalline phase. The phase changes of W, which depend on RH and temperature, are explained at the molecular level. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:2669,2680, 2004 [source] | |||||||||||||||||||||||||||||||||||||||||||||||||