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Selected AbstractsCalibrating conservation: new tools for measuring successCONSERVATION LETTERS, Issue 4 2008Valerie Kapos Abstract Conservation practitioners, policy makers, and donors agree that there is an urgent need to identify which conservation approaches are most likely to succeed in order to use more effectively the limited resources available for conservation. While recently developed standards of good practice in conservation are helpful, a framework for evaluation is needed that supports systematic analysis of conservation effectiveness. A conceptual framework and scorecard developed by the Cambridge Conservation Forum help to address common constraints to evaluating conservation success: unclear objectives, ineffective information management, the long time frames of conservation outcomes, scarcity of resources for evaluation, and lack of incentives for such evaluation. For seven major categories of conservation activity, the CCF tools help clarify conservation objectives and provide a standardized framework that is a useful basis for managing information about project outcomes and existing conservation experience. By identifying key outcomes that can predict conservation success and can be assessed in relatively short time frames, they help to make more efficient use of scarce monitoring and evaluation resources. With wide application, the CCF framework and evaluation tool can provide a powerful platform for drawing on the experience of past and ongoing conservation projects to identify quantitatively factors that contribute to conservation success. [source] Quantifying spatial classification uncertainties of the historical Wisconsin landscape (USA)ECOGRAPHY, Issue 2 2005Janine Bolliger Landscape feature can be classified by creating categories based on aggregation of spatially explicit information. However, many landscape features appear continuous rather than discrete. The aggregation process likely involves loss of information and introduces a variety of uncertainties whose degree and extent may differ spatially. Since landscape classifications have found wide application in e.g. natural resource policies or ecological research, assessments of spatial classification uncertainties are required. We present a quantitative framework to identify the degree of landscape continuity (fuzziness) and structure (categorization) based on fuzzy classification and offer measures to quantify uncertainties originating from aggregating features into categories. Fuzzy classification is a non-hierarchical, quantitative method of assessing class definitions using degrees of association between features and class. This results in classes which are well defined and compositionally distinct, as well as classes which are less clearly defined but which, to various degrees, share characteristics with some or all classes. The spatial variation in the degree of class definition on the landscape is used to assess classification uncertainties. The two aspects of uncertainty investigated are the degree of association of a feature with the overall class definitions (membership diffusion), and the class-specific degree of association of each pixel on the landscape with each class (membership saturation). Three classification scenarios, one fuzzy and one discrete, of the historical landscape of Wisconsin (USA) were compared for spatial classification uncertainties. Membership diffusion is highest in topographically heterogeneous environments, or areas characterized by many species occupying similar ecological niches. Classification uncertainties for individual classes show that differentiated species distributions can be identified, not only distribution centers. [source] Avoiding tragedies: a Flemish common and its commoners under the pressure of social and economic change during the eighteenth century1ECONOMIC HISTORY REVIEW, Issue 1 2009TINE DE MOOR Despite the wide application of the metaphor of ,the tragedy of the commons', there is little historical literature that points to the weaknesses of its historical basis. There is, however, sufficient qualitative and quantitative evidence to prove that commons were well regulated and organized in order to achieve a sustainable management, that also took into account the needs and wishes of its commoners. This case study of a common in Flanders looks at the evidence for this in the eighteenth century, examining bookkeeping and other archival sources. A model that incorporates the different functions of the commons (sustainability, efficiency, and utility) is explained and applied. [source] Synthesis of poly(N, N -dimethylacrylamide)- block -poly(ethylene oxide)- block -poly(N, N -dimethylacrylamide) and its application for separation of proteins by capillary zone electrophoresisELECTROPHORESIS, Issue 10 2010Jing Xu Abstract A series of well-defined triblock copolymers, poly(N, N -dimethylacrylamide)- block -poly(ethylene oxide)- block -poly(N, N -dimethylacrylamide) (PDMA- b -PEO- b -PDMA) synthesized by atom transfer radical polymerization, were used as physical coatings for protein separation. A comparative study of EOF showed that the triblock copolymer presented good capillary coating ability and EOF efficient suppression. The effects of the Mr of PDMA block in PDMA- b -PEO- b -PDMA triblock copolymer and buffer pH on the separation of basic protein for CE were investigated. Moreover, the influence of the copolymer structure on separation of basic protein was studied by comparing the performance of PDMA- b -PEO- b -PDMA triblock copolymer with PEO- b -PDMA diblock copolymer. Furthermore, the triblock copolymer coating showed higher separation efficiency and better migration time repeatability than fused-silica capillary when used in protein mixture separation and milk powder samples separation, respectively. The results demonstrated that the triblock copolymer coatings would have a wide application in the field of protein separation. [source] Assembly of Gold Nanoparticles in a Rod-Like Fashion Using Proteins as Templates,ADVANCED FUNCTIONAL MATERIALS, Issue 3 2006R. Bhattacharya Abstract An area of considerable current interest is the development of a practical approach for assembling inorganic nanoparticles into well-defined arrays because such a technique would offer immense opportunities leading to applications in microimaging, optoelectronics, therapeutics, etc. This paper illustrates a new, simple one-step process in which proteins act as templates to assemble gold nanoparticles in a shape-selective fashion. We show, for the first time, that antibodies to vascular endothelial growth factor 165 isoform, 2C3, and epidermal growth factor receptor can act as templates when present in solution during the synthesis of gold nanoparticles. These proteins direct the assembly of the gold nanoparticles into rod-like shapes when cooled to ,20,°C followed by thawing at room temperature. Immunoglobulin,G and bovine serum albumin can also direct the assembly process in a similar fashion; however, small molecules, such as poly(L -lysine) and lysine, cannot. The formation of a self-assembled structure in the form of a continuous rod, or the assembly of discrete nanoparticles in a rod-like fashion, can be tailored by controlling the ratio of the precursor gold salt, HAuCl4, to the antibody/protein used as the template. The nanoconjugates are characterized using UV-vis spectroscopy, transmission electron microscopy, and infrared spectroscopy. The nano-bioconjugates obtained via this process may find wide application in areas ranging from optoelectronics and biosensors to therapeutics in neoplastic disorders. [source] Identification of autoregressive models in the presence of additive noiseINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 5 2008Roberto Diversi Abstract A common approach in modeling signals in many engineering applications consists in adopting autoregressive (AR) models, consisting in filters with transfer functions having a unitary numerator, driven by white noise. Despite their wide application, these models do not take into account the possible presence of errors on the observations and cannot prove accurate when these errors are significant. AR plus noise models constitute an extension of AR models that consider also the presence of an observation noise. This paper describes a new algorithm for the identification of AR plus noise models that is characterized by a very good compromise between accuracy and efficiency. This algorithm, taking advantage of both low and high-order Yule,Walker equations, also guarantees the positive definiteness of the autocorrelation matrix of the estimated process and allows to estimate the equation error and observation noise variances. It is also shown how the proposed procedure can be used for estimating the order of the AR model. The new algorithm is compared with some traditional algorithms by means of Monte Carlo simulations. Copyright © 2007 John Wiley & Sons, Ltd. [source] Modelling & Controlling Monetary and Economic Identities with Constrained State Space ModelsINTERNATIONAL STATISTICAL REVIEW, Issue 2 2007Gurupdesh S. Pandher Summary The paper presents a method for modelling and controlling time series with identity structures. The approach is presented in the context of monetary targeting where the monetary identity (e.g. reserve money equals net foreign assets plus domestic credit) is modelled using a constrained state space model and next-period changes in domestic credit (policy variable) are estimated to reach the target level of reserve money. The constrained modelling ensures that aggregation and identity relations among items are dynamically satisfied during estimation, leading to more accurate forecasting and targeting. Applications to Germany, UK and USA show that the constrained state space model provides significant improvements in targeting and forecasting performance over the AR(1) benchmark and the unconstrained model. Reduction in the mean square error of targeting over AR(1) is in the range of 76,95% for the three countries while the gain in targeting efficiency over unconstrained modelling is between 21% and 55%. Beyond monetary targeting, the method has wide application to the dynamic modelling and control of economic and financial time series with identity and aggregation constraints (e.g. balance of payment, national income, purchasing power parity, company balance sheet). Résumé L'article présente une méthode de modélisation et de contrôle des séries temporelles avec des structures d'identité. L'approche est présentée dans le contexte de ciblage monétaire où l'identité monétaire (c. à d. monnaie de réserve égale avoirs étrangers plus crédit intérieur) est modélisée en utilisant un modèle spatial sous contrainte et où les variations du crédit intérieur à la période suivante (variable de politique) sont estimés pour atteindre le niveau visé de monnaie de réserve. La modélisation sous contrainte assure que les relations d'agrégation et d'identité entre items sont satisfaites en dynamique dans l'estimation, ce qui conduit à des prévisions et ciblages plus précis. L'application à l'Allemagne, le Royaume-Uni et les USA montrent que le modèle contraint apporte des améliorations importantes dans la performance de ciblage et de prévision par rapport à l'étalonnage auto-régressif (1) et au modèle sans contrainte. La réduction d'erreur du moindre carré par rapport à l'AR est comprise entre 76 et 95% pour les trois pays tandis que le gain en efficacité de ciblage sur le modèle sans contrainte se situe entre 21 et 55%. Par delà le ciblage monétaire, la méthode a une large application à la modélisation dynamique et au contrôle des séries temporelles économiques et financières avec des contraintes d'identité et d'agrégation (par ex. la balance des paiements, le revenu national, la parité de pouvoir d'achat, le bilan d'une compagnie). [source] Synthesis, characterization, and degradation of poly(ester-anhydride) for particulate deliveryISRAEL JOURNAL OF CHEMISTRY, Issue 4 2005Sweta Modi A series of poly(ester-anhydride) from poly(lactic acid) and poly(sebacic acid) have been synthesized and characterized. Poly(lactic acid) of molecular weight 2,550 Da has been synthesized from pharmaceutical grade lactic acid. The copolymers are in the molecular weight range of 3,000-15,000 Da, with the higher molecular weights obtained for the polymers with higher sebacic acid content. With increase in sebacic acid content, the melting point is also found to increase. The polymers with 50% or more poly(sebacic acid) content melt between 80 and 84 °C. These polymers have been formulated into microspheres and their degradation studied. Due to their biodegradability and the flexibility to alter their degradation profile, they find a wide application in drug delivery. [source] Pastoralist's livestock and settlements influence game bird diversity and abundance in a savanna ecosystem of southern KenyaAFRICAN JOURNAL OF ECOLOGY, Issue 1 2009Dana L. Morris Abstract We investigated the vegetation structure and density of game birds along a successional gradient created by varying intensity of human settlement in a pastoral community in Shompole group ranch in southern Kenya. We examined four habitat types including heavily-grazed grass in currently occupied settlements, short grass in seasonal settlements, patches of bushed woodland in settlement sites that had been abandoned up to 30 years ago, and tall grass in a wildlife sanctuary. Vegetation biomass was the highest in the sanctuary where livestock are excluded and the lowest in the vicinity of currently occupied settlements. Abundance of doves (Oena spp. and Streptopelia spp.) was best associated with moderate grazing and per cent green grass, which provide good foraging opportunities. Francolin and spurfowl (Francolinus spp.) were positively associated with vegetation biomass. Quail (Coturnix spp.) were positively associated with tree cover. These data reflect the importance of maintaining a balance of wildlife and livestock grazing with patches of ungrazed grasslands and bushed woodlands in providing a mosaic of habitats that support a diverse population of game birds. The results have wide application for an integrated management approach to livestock, wildlife and game bird management in the savannas. Résumé Nous avons étudié la structure de la végétation et la densité du gibier à plume le long d'un gradient créé par la variation de l'intensité des installations humaines, dans une communauté pastorale dans un ranch de Shompole, dans le sud du Kenya. Nous avons examiné quatre types d'habitats: l'herbe fortement broutée dans les installations qui sont actuellement occupées, l'herbe courte des installations saisonnières, les îlots de broussailles dans les anciennes installations abandonnées parfois depuis 30 ans et les hautes herbes d'un sanctuaire de la faune. La biomasse de la végétation était la plus grande dans le sanctuaire d'où le bétail était exclu et la plus basse dans le voisinage des installations encore occupées. L'abondance des tourterelles (Oena spp. et Streptopelia spp.) était plutôt liée à un broutage modéré et à un pourcentage d'herbe verte qui donnent de bonnes possibilités de se nourrir. Les francolins (Francolinus spp.) étaient positivement liés à la biomasse de la végétation. Les cailles (Coturnix spp.) étaient positivement liées à la couverture arborée. Ces données reflètent l'importance de conserver un équilibre entre les pâturages de la faune sauvage et du bétail et des îlots non pâturés et des broussailles, pour créer une mosaïque d'habitats qui accueillent une population variée de gibier à plume. Les résultats peuvent largement trouver une application dans les approches intégrées de gestion du bétail, de la faune sauvage et du gibier à plume en savane. [source] More economic 25 mg 13C-urea breath test can be effective in detecting primary Helicobacter pylori infection in childrenJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 3 2007Yao-Jong Yang Abstract Background and Aim:, The high cost of the 13C-urea breath test (UBT) limits its wide application for both epidemiological and clinical studies for diagnosing Helicobacter pylori infection. This study examined if a lower-dose UBT, applying 1 mg/kg of bodyweight (maximum 25 mg, UBT25), could introduce cost savings while preserving high diagnostic yields for primary H. pylori infection. Methods:, Children aged less than 16 years were recruited after obtaining consent. Those children with administration of antibiotics or proton pump inhibitors within 1 month of the tests were excluded. Positive tests for both the UBT with 50 mg urea (UBT50) and the H. pylori stool antigen (HpSA) were qualifying criteria for H. pylori infection. Negative results for both indicated non-infection. The UBT25 was conducted 1 week after the UBT50. The cut-off points for the UBT25 ranging from 2, to 5, were examined for their sensitivity, specificity and accuracy rates. Results:, A total of 153 children were recruited (55% male; mean age 9.1 ± 3.5 years). Both the UBT50 and HpSA test were positive in 18 (13.1%) and negative in 119 children, respectively. The sensitivity and specificity of the UBT25 were optimally achieved at 88.9% (95% confidence interval [CI]: 71.4,100) and 95.0% (95% CI: 91.1,99.9), judged with a cut-off point at 3.5,. The diagnostic accuracy was significantly higher for children older than 7 years than for those younger than 7 years (98%vs 85%, P = 0.009). Conclusion:, Lower-dose UBT titration by bodyweight can cut costs while maintaining a highly reliable method to screen primary H. pylori infection in children older than 7 years, which is generally beyond school age. [source] Progress in the Study of Molecular Genetic Improvements of Poplar in ChinaJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 9 2006Shan-Zhi Lin Abstract The poplar is one of the most economically important and intensively studied tree species owing to its wide application in the timber industry and as a model material for the study of woody plants. The natural resource of poplars in China is replete. Over the past 10 years, the application of molecular biological techniques to genetic improvements in poplar species has been widely studied in China. Recent advances in molecular genetic improvements of poplar, including cDNA library construction, gene cloning and identification, genetic engineering, gene expression, genetic linkage map construction, mapping of quantitative trait loci (QTL) and molecular-assisted selection, are reviewed in the present paper. In addition, the application of modern biotechnology to molecular improvements in the genetic traits of the poplar and some unsolved problems are discussed. (Managing editor: Li-Hui Zhao) [source] Use of PSA Measurement in PracticeJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 6 2001APRN-C, Mary Jo Goolsby EdD The Clinical Practice Guideline (CPG) series provides an overview of one CPG each month. The overview includes a brief summary of the guideline's content, as well as the identification of some factors by which the author has critiqued it. The first article in the series reviewed the steps of CPG critique. Subsequent columns have described CPGs related to viral upper respiratory illnesses, tobacco dependence, menopause and perimenopause, and musculoskeletal evaluation. This month, the column describes a CPG titled: Prostate-Specific Antigen (PSA) Best Practice Policy, from the American Urological Association (AUA). As prostate cancer is the leading cause of cancer deaths among U.S. men, this set of recommendations should have wide application. [source] Phylogenetic analyses of Caulerpa taxifolia (Chlorophyta) and of its associated bacterial microflora provide clues to the origin of the Mediterranean introductionMOLECULAR ECOLOGY, Issue 4 2001I. Meusnier Abstract The accidental introduction of Caulerpa taxifolia into the Mediterranean is no longer under dispute. What has eluded researchers until now, is definitive evidence for the original, biogeographical source population. Here we present two independent lines of evidence that support an Australian origin for the Mediterranean populations of C. taxifolia. First, we reanalysed algal rDNA-internal transcribed spacer (rDNA-ITS) sequences, combining previously published sequences from different studies with 22 new sequences. The ITS sequence comparison showed that the Australian sample is the sister group of the Mediterranean,aquarium clade. Second, cloned bacterial 16S rDNA gene sequences were analysed from the associated microflora of C. taxifolia collected from Australia, Tahiti, the Philippines and the Mediterranean. Five bacterial lineages were identified, of which three were dominant. Alpha Proteobacteria were the most abundant and were found in all samples. In contrast, members of the beta Proteobacterial line and Cytophaga-Flexibacter-Bacteroides line (CFB) were mainly associated with Mediterranean and Australian samples. Frequency distributions of the five bacterial lineages were significantly different among biogeographical locations. Phylogenetic analyses of the 54 bacterial sequences derived from the four C. taxifolia individuals resulted in a well-resolved tree with high bootstrap support. The topologies of the beta Proteobacteria and CFB mirror the geographical sources of their algal hosts. Bacterial,algal associations provide an identification tool that may have wide application for the detection of marine invasions. [source] Review article: Use of renal registry data for research, health-care planning and quality improvement: What can we learn from registry data in the Asia,Pacific region?NEPHROLOGY, Issue 8 2008TECK-ONN LIM SUMMARY: We review renal registry data from the Asia,Pacific region with an emphasis on their uses in health care and in dialysis care in particular. The review aims to demonstrate the information value of registry data. While renal registry provides a useful data resource for epidemiological research, there are severe methodological limitations in its application for analytical or therapeutic research. However, it is the use of renal registry data for public health and health-care management purposes that registry really comes into its own, and it is primarily for these that governments have invested in national patient and disease registries. We apply data from several renal registries in the Asia,Pacific region to illustrate its wide application for planning dialysis services, for evaluating dialysis practices and health outcomes, with a view to improving the quality of dialysis care. In the course of preparing the review, we have found that the quality and accessibility of renal registry data were highly variable across the region. Given the value of renal registry, every country in the Asia,Pacific region should establish one or should ensure that their current registries are better resourced and developed. Greater data sharing and collaboration among registries in the region could help advance the nephrology to serve our patients better. [source] Preparation of starch and soluble sugars of plant material for the analysis of carbon isotope composition: a comparison of methods,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 16 2009Andreas Richter Starch and soluble sugars are the major photosynthetic products, and their carbon isotope signatures reflect external versus internal limitations of CO2 fixation. There has been recent renewed interest in the isotope composition of carbohydrates, mainly for use in CO2 flux partitioning studies at the ecosystem level. The major obstacle to the use of carbohydrates in such studies has been the lack of an acknowledged method to isolate starch and soluble sugars for isotopic measurements. We here report on the comparison and evaluation of existing methods (acid and enzymatic hydrolysis for starch; ion-exchange purification and compound-specific analysis for sugars). The selectivity and reproducibility of the methods were tested using three approaches: (i) an artificial leaf composed of a mixture of isotopically defined compounds, (ii) a C4 leaf spiked with C3 starch, and (iii) two natural plant samples (root, leaf). Starch preparation methods based on enzymatic or acid hydrolysis did not yield similar results and exhibited contaminations by non-starch compounds. The specificity of the acidic hydrolysis method was especially low, and we therefore suggest terming these preparations as HCl-hydrolysable carbon, rather than starch. Despite being more specific, enzyme-based methods to isolate starch also need to be further optimized to increase specificity. The analysis of sugars by ion-exchange methods (bulk preparations) was fast but produced more variable isotope compositions than compound-specific methods. Compound-specific approaches did not in all cases correctly reproduce the target values, mainly due to unsatisfactory separation of sugars and background contamination. Our study demonstrates that, despite their wide application, methods for the preparation of starch and soluble sugars for the analysis of carbon isotope composition are not (yet) reliable enough to be routinely applied and further research is urgently needed to resolve the identified problems. Copyright © 2009 John Wiley & Sons, Ltd. [source] The promise of geometric morphometricsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue S35 2002Joan T. Richtsmeier Abstract Nontraditional or geometric morphometric methods have found wide application in the biological sciences, especially in anthropology, a field with a strong history of measurement of biological form. Controversy has arisen over which method is the "best" for quantifying the morphological difference between forms and for making proper statistical statements about the detected differences. This paper explains that many of these arguments are superfluous to the real issues that need to be understood by those wishing to apply morphometric methods to biological data. Validity, the ability of a method to find the correct answer, is rarely discussed and often ignored. We explain why demonstration of validity is a necessary step in the evaluation of methods used in morphometrics. Focusing specifically on landmark data, we discuss the concepts of size and shape, and reiterate that since no unique definition of size exists, shape can only be recognized with reference to a chosen surrogate for size. We explain why only a limited class of information related to the morphology of an object can be known when landmark data are used. This observation has genuine consequences, as certain morphometric methods are based on models that require specific assumptions, some of which exceed what can be known from landmark data. We show that orientation of an object with reference to other objects in a sample can never be known, because this information is not included in landmark data. Consequently, a descriptor of form difference that contains information on orientation is flawed because that information does not arise from evidence within the data, but instead is a product of a chosen orientation scheme. To illustrate these points, we apply superimposition, deformation, and linear distance-based morphometric methods to the analysis of a simulated data set for which the true differences are known. This analysis demonstrates the relative efficacy of various methods to reveal the true difference between forms. Our discussion is intended to be fair, but it will be obvious to the reader that we favor a particular approach. Our bias comes from the realization that morphometric methods should operate with a definition of form and form difference consistent with the limited class of information that can be known from landmark data. Answers based on information that can be known from the data are of more use to biological inquiry than those based on unjustifiable assumptions. Yrbk Phys Anthropol 45:63,91, 2002. © 2002 Wiley-Liss, Inc. [source] The Hull and White Model of the Short Rate: An Alternative Analytical RepresentationTHE JOURNAL OF FINANCIAL RESEARCH, Issue 4 2002Dwight Grant Abstract Hull and White extend Ho and Lee's no-arbitrage model of the short interest rate to include mean reversion. This addition eliminates the problem of negative interest rates and has found wide application. To implement their model, Hull and White employ a sequential search process to identify the mean interest rate in a trinomial lattice at each date. In this article we extend Hull and White's work by developing an analytical solution for the mean interest rate at each date. This solution applies equally well to trinomial lattices, interest rate trees, and Monte Carlo simulation. We illustrate the analytical result by applying it to an example originally used by Hull and White and then for valuing an option on a bond. [source] Economic profitability of Nile tilapia (Oreochromis niloticus L.) production in KenyaAQUACULTURE RESEARCH, Issue 11 2007Aloyce R Kaliba Abstract Economic profitability of Nile tilapia production in Kenya was analysed using a model that simulated individual fish growth and took fish population dynamics in the pond into account. The results suggest that the currently practiced mixed-sex tilapia culture is economically unsustainable. It is suggested that research and extension efforts be geared towards developing monosex Nile tilapia production systems. Nile tilapia culture with African catfish predation should be viewed as an intermediate step towards all-male Nile tilapia culture. This will allow accumulation of both physical and human capital to support all-male tilapia culture. Under all-male culture, economic returns are high enough to justify investment in Nile tilapia culture using borrowed capital. However, the success of monosex culture will depend on the availability and affordability of quality fingerlings and low-cost fish feeds. The results have a wide application in Sub-Saharan Africa where mixed-sex Nile tilapia culture is common. [source] A GRAPHICAL DIAGNOSTIC FOR VARIANCE FUNCTIONSAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 3 2007Iain Pardoe Summary This paper proposes diagnostic plots for regression variance functions. It shows how to extend graphical methodology that uses Bayesian sampling for checking the regression mean function to also check the variance function. Plots can be constructed quickly and easily for any model of interest. These plots help to identify model weaknesses and can suggest ways to make improvements. The proposed methodology is illustrated with two examples: a simple linear regression model to fix ideas, and a more complex study involving count data to demonstrate the potential for wide application. [source] Spousal concordance and reliability of the ,Prudence Score' as a summary of diet and lifestyleAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 4 2009Sanjoti Parekh Abstract Objectives: This paper describes a composite ,Prudence Score' summarising self-reported behavioural risk factors for non-communicable diseases. If proved robust, the ,Prudence score' might be used widely to encourage large numbers of individuals to adopt and maintain simple, healthy changes in their lifestyle. Methods: We calculated the ,Prudence Score' based on responses collected in late 2006 to a postal questionnaire sent to 225 adult patients aged 25 to 75 years identified from the records of two general medical practices in Brisbane, Australia. Participants completed the behavioural, dietary and lifestyle items in relation to their spouse as well as themselves. The spouse or partner of each addressee completed their own copy of the study questionnaire. Results: Kappa scores for spousal concordance with probands' reports (n = 45 pairs) on diet-related items varied between 0.35 (for vegetable intake) to 0.77 (for usual type of milk consumed). Spousal concordance values for other behaviours were 0.67 (physical activity), 0.82 (alcohol intake) and 1.0 (smoking habits). Kappa scores for test-retest reliability (n = 53) varied between 0.47 (vegetable intake) and 0.98 (smoking habits). Conclusion: The veracity of self-reported data is a challenge for studies of behavioural change. Our results indicate moderate to substantial agreement from life partners regarding individuals' self-reports for most of the behavioural risk items included in the ,Prudence Score'. This increases confidence that key aspects of diet and lifestyle can be assessed by self-report. Implications: The ,Prudence Score' potentially has wide application as a simple and robust tool for health promotion programs. [source] Generation of high rapamycin producing strain via rational metabolic pathway-based mutagenesis and further titer improvement with fed-batch bioprocess optimizationBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010Xiangcheng Zhu Abstract Rapamycin is a triene macrolide antibiotic produced by Streptomyces hygroscopicus. Besides its wide application as an effective immunosuppressive agent, other important bioactivities have made rapamycin a potential drug lead for novel pharmaceutical development. However, the low titer of rapamycin in the original producer strain limits further industrialization efforts and restricts its use for other applications. Predicated on knowledge of the metabolic pathways related to rapamycin biosynthesis in S. hygroscopicus, we have rationally designed approaches to generate a rapamycin high producer strain of S. hygroscopicus HD-04-S. These have included alleviation of glucose repression, improved tolerance towards lysine and shikimic acid, and auxotrophy of tryptophan and phenylalanine through the application of stepwise UV mutagenesis. The resultant strain produced rapamycin at 450,mg/L in the shake flask scale. These fermentations were further scaled up in 120 and 20,000,L fermentors, respectively, at the pilot plant. Selected fermentation factors including agitation speed, pH, and on-line supplementation were systematically evaluated. A fed-batch strategy was established to maximize rapamycin production. With these efforts, an optimized fermentation process in the larger scale fermentor was developed. The final titer of rapamycin was 812,mg/L in the 120,L fermentor and 783,mg/L in the 20,000,L fermentor. This work highlights a high rapamycin producing strain derived by mutagenesis and subsequent screening, fermentation optimization of which has now made it feasible to produce rapamycin on an industrial scale by fermentation. The strategies developed here should also be applicable to titer improvement of other important microbial natural products on an industrial scale. Biotechnol. Bioeng. 2010;107: 506,515. © 2010 Wiley Periodicals, Inc. [source] Blunt atrial transseptal puncture using excimer laser in swine,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2007Abdalla A. Elagha MD Abstract Objectives: We describe a new approach that may enhance safety of atrial transseptal puncture using a commercially available laser catheter that is capable of perforation only when energized. We test this approach in swine. Background: Despite wide application, conventional needle transseptal puncture continues to risk inadvertent nontarget perforation and its consequences. Methods: We used a commercial excimer laser catheter (0.9-mm Clirpath, Spectranetics). Perforation force was compared in vitro with a conventional Brockenbrough needle. Eight swine underwent laser transseptal puncture under X-ray fluoroscopy steered using a variety of delivery catheters. Results: The 0.9-mm laser catheter traversed in vitro targets with reduced force compared with a Brockenbrough needle. In vitro, the laser catheter created holes that were 25,30% larger than the Brockenbrough needle. Laser puncture of the atrial septum was successful and accurate in all animals, evidenced by oximetry, pressure, angiography, and necropsy. The laser catheter was steered effectively using a modified Mullins introducer sheath and using two different deflectable guiding catheters. The mean procedure time was 15 ± 6 min, with an average 3.0 ± 0.8 sec of laser activation. There were no adverse sequelae after prolonged observation. Necropsy revealed discrete 0.9-mm holes in all septae. Conclusion: Laser puncture of the interatrial septum is feasible and safe in swine, using a blunt laser catheter that perforates tissues in a controlled fashion. © 2007 Wiley-Liss, Inc. [source] Glycosyltransferases and their AssaysCHEMBIOCHEM, Issue 14 2010Dr. Gerd K. Wagner Abstract Glycosyltransferases (GTs) are a large family of enzymes that are essential in all domains of life for the biosynthesis of complex carbohydrates and glycoconjugates. GTs catalyse the transfer of a sugar from a glycosyl donor to a variety of acceptor molecules, for example, oligosaccharides, peptides, lipids or small molecules. Such glycosylation reactions are central to many fundamental biological processes, including cellular adhesion, cell signalling and bacterial- and plant-cell-wall biosynthesis. GTs are therefore of significant interest as molecular targets in chemical biology and drug discovery. In addition, GTs have found wide application as synthetic tools for the preparation of complex carbohydrates and glycoconjugates. In order to exploit the potential of GTs both as molecular targets and synthetic tools, robust and operationally simple bioassays are essential, especially as more and more protein sequences with putative GT activity but unknown biochemical function are being identified. In this minireview, we give a brief introduction to GT biochemistry and biology. We outline the relevance of GTs for medicinal chemistry and chemical biology, and describe selected examples for recently developed GT bioassays, with a particular emphasis on fluorescence-based formats. [source] A New Protein Engineering Approach Combining Chemistry and Biology, Part I; Site-Specific Incorporation of 4-Iodo- L -phenylalanine in vitro by Using Misacylated Suppressor tRNAPheCHEMBIOCHEM, Issue 10 2006Koichiro Kodama Abstract An Escherichia coli suppressor tRNAPhe (tRNAPheCUA) was misacylated with 4-iodo- L -phenylalanine by using the A294G phenylalanyl,tRNA synthetase mutant (G294-PheRS) from E. coli at a high magnesium-ion concentration. The preacylated tRNA was added to an E. coli cell-free system and a Ras protein that contained the 4-iodo- L -phenylalanine residue at a specific target position was synthesized. Site-specific incorporation of 4-iodo- L -phenylalanine was confirmed by using LC,MS/MS. Free tRNAPheCUA was not aminoacylated by aminoacyl,tRNA synthetases (aaRSs) present in the E. coli cell-free system. Our approach will find wide application in protein engineering since an aryl iodide tag on proteins can be used for site-specific functionalization of proteins. [source] Desymmetrisation of a Centrosymmetric Molecule by Carbon,Carbon Bond Formation: Asymmetric Aldol Reactions of a Centrosymmetric DialdehydeCHEMISTRY - A EUROPEAN JOURNAL, Issue 20 2007Karen Dodd Abstract The desymmetrisation of centrosymmetric molecules by enantioselective carbon,carbon bond formation has been reported for the first time. A bimetallic zinc catalyst developed by Trost was exploited in the desymmetrisation of a centrosymmetric dialdehyde. The approach was successful with a range of ketone nucleophiles and was uniformly highly diastereoselective (>98:<2). The yield and the enantioselectivity of the reaction varied as a function of the ketone used, and the desymmetrised products were obtained in up to 74,% yield and 97,%,ee (ee=enantiomeric excess). The desymmetrisation of centrosymmetric molecules by enantioselective carbon,carbon bond formation is an efficient and convergent synthetic approach which is likely to find wide application in synthesis, particularly in the total synthesis of natural products with embedded centrosymmetric fragments. [source] Development of Pharmaceutical Drugs, Drug Intermediates and Ingredients by Using Direct Organo-Click ReactionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2008Dhevalapally B. Ramachary Abstract Here we report on our studies of the use of combinations of amino acids, amines, K2CO3 or Cs2CO3 and CuSO4/Cu for catalysing green cascade reactions. We aimed to prepare the highly reactive and substituted olefin species 7 and 8, under very mild and environmentally friendly conditions, thus giving the hydrogenated products 10 and 12 through the action of Hantzsch ester (4) by self-catalysis through decreasing the HOMO,LUMO energy gaps between olefins 7/8 and Hantzsch ester (4) through biomimetic reductions. Highly useful compounds 10 to 14 were assembled from simple substrates such as aldehydes 1, ketones 2, CH acids 3, Hantzsch ester (4) and alkyl halides 5 by diversity-oriented green synthesis involving cascade olefination/hydrogenation (O/H), olefination/hydrogenation/alkylation (O/H/A) and hydrogenation/olefination/hydrogenation (H/O/H) reaction sequences in one-pot fashion with stereospecific organo- and organo-/metal-carbonate catalysis. Highly functionalized diverse compounds such as 10 to 14 are biologically active products and have found wide applications as pharmaceutical drugs, drug intermediates and drug ingredients. For the first time in organocatalysis, we report the O/H/A/TE reaction to furnish high yields of transesterification products 11 by simply mixing the reactants under proline/K2CO3 catalysis conditions. Additionally, a novel organocatalytic H/O/H reaction sequence for the synthesis of alkyl-substituted aromatics has been developed. Furthermore, for the first time we have developed organocatalysed cascade olefination/hydrogenation/hydrolysis (O/H/H) reactions to furnish highly useful materials such as 2-oxochroman-3-carboxylic acid (14kc) and 2-amino-4H -chromene-3-carbonitrile (14kj) in good yields. Experimentally simple and environmentally friendly organocatalytic two-carbon homologation through cascade O/H/H reactions of aldehydes 1, Meldrum's acid (3c), Hantzsch ester (4) and acetic acid/triethylamine in ethanol has been demonstrated. Additionally, we have developed a green synthesis of the highly substituted 1,2,3-triazole 17 from simple substrates through a two-step combination of olefination/hydrogenation/alkylation and Huisgen cycloaddition reaction sequences under stereospecific organocopper catalysis conditions. In this paper we have found strong support for our hypothesis that, "decreasing the HOMO,LUMO energy gap between olefins 7/8 and Hantzsch ester (4) will drive the biomimetic hydrogenation reaction by self-catalysis". This self-catalysis was further confirmed with many varieties of examples.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] One-Pot Preparation of Polymer,Enzyme,Metallic Nanoparticle Composite Films for High-Performance Biosensing of Glucose and GalactoseADVANCED FUNCTIONAL MATERIALS, Issue 11 2009Yingchun Fu Abstract New polymer,enzyme,metallic nanoparticle composite films with a high-load and a high-activity of immobilized enzymes and obvious electrocatalysis/nano-enhancement effects for biosensing of glucose and galactose are designed and prepared by a one-pot chemical pre-synthesis/electropolymerization (CPSE) protocol. Dopamine (DA) as a reductant and a monomer, glucose oxidase (GOx) or galactose oxidase (GaOx) as the enzyme, and HAuCl4 or H2PtCl6 as an oxidant to trigger DA polymerization and the source of metallic nanoparticles, are mixed to yield polymeric bionanocomposites (PBNCs), which are then anchored on the electrode by electropolymerization of the remaining DA monomer. The prepared PBNC material has good biocompatibility, a highly uniform dispersion of the nanoparticles with a narrow size distribution, and high load/activity of the immobilized enzymes, as verified by transmission/scanning electron microscopy and electrochemical quartz crystal microbalance. The thus-prepared enzyme electrodes show a largely improved amperometric biosensing performance, e.g., a very high detection sensitivity (99 or 129,µA cm,2 mM,1 for glucose for Pt PBNCs on bare or platinized Au), a sub-micromolar limit of detection for glucose, and an excellent durability, in comparison with those based on conventional procedures. Also, the PBNC-based enzyme electrodes work well in the second-generation biosensing mode. The proposed one-pot CPSE protocol may be extended to the preparation of many other functionalized PBNCs for wide applications. [source] Layer-By-Layer Assembly of ,-Estradiol Loaded Mesoporous Silica Nanoparticles on Titanium Substrates and Its Implication for Bone HomeostasisADVANCED MATERIALS, Issue 37 2010Yan Hu Drug-loadingmesoporous silica nanoparticles that serve as a nanoreservoir-type drug-delivery system are successfully attached to titanium substrates via the layer-by-layer assembly technique (see scheme). The obtained structure demonstrates great potential for regulating the biological behaviors of osteoblasts/ steoclasts in order to maintain bone homeostasis. The approach we present here may have wide applications in implant technology, tissue engineering, and regenerative medicine. [source] Homogeneously Dispersed Ceria Nanocatalyst Stabilized with Ordered Mesoporous AluminaADVANCED MATERIALS, Issue 13 2010Quan Yuan Homogeneously dispersed ceria nanocatalyst can be synthesized and stabilized with ordered mesoporous alumina by a one-step sol,gel method. This novel material possesses high thermal stability and exhibits 100% conversion at room temperature for CO oxidation when loaded with Au. This established approach can be expanded to the controlled synthesis and stabilization of other nanocatalysts with wide applications. [source] A comparison of changes in the transformation of isoflavones in soymilk using varying concentrations of exogenous and probiotic-derived endogenous , -glucosidasesJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2007D.O. Otieno Abstract Aims:, To compare endogenous and exogenous , -glucosidases for the hydrolysis of the predominant isoflavone glucosides in soymilk in order to improve the biological activity. Methods and Results:,, -glucosidase activity of probiotic organisms, including Bifidobacterium animalis ssp. lactis Bb12, Lactobacillus acidophilus ATCC 4461 and Lactobacillus casei 2607 in soymilk, was evaluated and was related to the increase in the concentration of isoflavone aglycones during fermentation. The concentrations of isoflavone compounds in soymilk were monitored using a Varian model HPLC with an Amperometric electrochemical detector. The aglycone composition, also known as aglycone equivalent ratio, has been considered to be important for the delivery of health benefits of isoflavones, and was monitored during the fermentation of soymilk. Comparison of the hydrolytic effectiveness of both exogenous and endogenous enzyme during 4-h incubation in soymilk was conducted using the Otieno,Shah (O,S) index. Results showed that exogenous enzyme exhibited faster rate of isoflavone glucoside hydrolysis than that by endogenous enzyme. Highest O,S indices were obtained after 4, 3 and 2 h of incubation with enzyme solution having , -glucosidase activity of 0·288 U ml,1, 0·359 U ml,1 and 0·575 U ml,1, resulting into aglycone concentration increments of 5·87-, 6·07- and 5·94-fold, respectively. Conversely, aglycone concentration in the soymilk with B. animalis ssp. lactis Bb12, L. casei 2607 and L. acidophilus 4461 increased by 3·43-, 2·72- and 3·03-fold, respectively, after 4 h of fermentation at 37°C. In addition, the O,S index of endogenous enzyme was much lower than that of the exogenous enzyme over the same 4-h incubation period. Optimum aglycone equivalent ratios coincided with highest O,S indices and highest aglycone concentrations in soymilk hydrolysed with exogenous enzyme. The same correlation of O,S indices and highest aglycone concentrations occurred for endogenous enzyme during the 24 h of fermentation. Conclusions:, Obtaining highest aglycone concentration and optimum aglycone equivalent ratio could provide a critical beginning point in clinical trials for the realization of unique health benefits of soy isoflavones. Significance and Impact of the Study:, Screening for , -glucosidase activities of probiotics in soymilk and comparing their hydrolytic potentials with that of exogenous , -glucosidase could find wide applications in the development of different aglycone-rich functional soy beverages. [source] | ||||||||||||||||||||||||||||||||||