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Promising Directions (promising + direction)
Selected AbstractsAdvancing public sector performance analysisAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 5 2008Carolyn J. Heinrich Abstract Recent reforms intended to promote more accountable and responsive government have increased public attention to performance analysis and accelerated the production and use of information on agency performance and public program outcomes. Drawing from cases and empirical studies, this presentation considers questions about what should count as evidence, how it should be communicated, who should judge the quality and reliability of evidence and performance information, and how to achieve a balance between processes that produce rigorous information for decision making and those that foster democratic governance and accountability. Promising directions are suggested for efforts to improve government effectiveness through the use of more rigorous information in decision making, along with acknowledgment of the limitations and risks associated with such efforts. Copyright © 2008 John Wiley & Sons, Ltd. [source] Allometric growth, life-history invariants and population energeticsECOLOGY LETTERS, Issue 4 2005Evan P. Economo Abstract Population and community level processes must be at least partially determined by variation in the body sizes of constituent individuals, implying quantitative scaling relations can be extended to account for variation in those processes. Here we integrate allometric growth and life-history invariant theories, and use this approach to develop theory describing the energetics of stationary populations. Our predictions approximate, with no free parameters, the scaling of production/biomass and assimilation/biomass ratios in mammalian populations and work partially for fish populations. This approach appears to be a promising direction and suggests the need for further development of the growth and life-history models, and extensions of those theories. [source] Topology and Dependency Tests in Spatial and Network Autoregressive ModelsGEOGRAPHICAL ANALYSIS, Issue 2 2009Steven Farber Social network analysis has been identified as a promising direction for further applications of spatial statistical and econometric models. The type of network analysis envisioned is formally identical to the analysis of geographical systems, in that both involve the measurement of dependence between observations connected by edges that constitute a system. An important item, which has not been investigated in this context, is the potential relationship between the topology properties of networks (or network descriptions of geographical systems) and the properties of spatial models and tests. The objective of this article is to investigate, within a simulation setting, the ability of spatial dependency tests to identify a spatial/network autoregressive model when two network topology measures, namely degree distribution and clustering, are controlled. Drawing on a large data set of synthetically controlled social networks, the impact of network topology on dependency tests is investigated under a hierarchy of topology factors, sample size, and autocorrelation strength. In addition, topology factors are related to known properties of empirical systems. El análisis de redes sociales ha sido y es una dirección prometedora en el avance de las aplicaciones de modelos econométricos y de estadística espacial. El tipo de análisis de redes que proponemos es idéntico al análisis de sistemas geográficos, ya que ambos miden la dependencia entre observaciones conectadas que conforman un sistema. Un punto importante que no ha sido investigado en este contexto es la potencial relación entre las propiedades topológicas de redes (o descripción de redes de sistemas geográficos) y las propiedades de los modelos y pruebas (tests) espaciales. El objetivo de este artículo es investigar (dentro del marco de simulaciones Monte Carlo), la capacidad que poseen las pruebas de dependencia espacial para identificar un modelo autorregresivo espacial/de redes, en los casos en los que dos medidas topológicas de redes (grado de distribución y transitividad) son controlados. Haciendo uso de una base de datos de redes sociales controladas sintéticamente, este artículo evalúa el impacto de la topología de redes en las pruebas de dependencia espacial. Dicho impacto es evaluado con respecto a variaciones en los factores topológicos, el tamaño de muestra, y los niveles de autocorrelación espacial. Adicionalmente, los factores topológicos son relacionados a propiedades conocidas de varios sistemas empíricos. [source] All modes lead to home: assessing the state of the remittance artGLOBAL NETWORKS, Issue 1 2009EMMANUEL YUJUICO Abstract The art of sending remittances overlaps with migration, technological innovation and marketing , three of globalization's driving forces. All things being equal, the role of innovation with regard to remittances is to reduce transaction costs in making these transfers. Yet, other aspects of the marketing mix come into play apart from the price of sending remittances such as product user-friendliness, the location of senders and beneficiaries, and the promotion of these technologies. In this article, I assess the state of the remittance art in terms of meeting the needs of remittance senders and beneficiaries and future directions that this domain may take due to further diffusion of innovations. Remittance technologies represent a promising direction in which cutting edge technology is harnessed to focus on developing world concerns. By enlisting the talents of the world's foremost product and service designers, private sector initiatives such as these can play a role in helping ease poverty's penalties. [source] Heterotachy and Functional Shift in Protein EvolutionIUBMB LIFE, Issue 4-5 2003Hervé Philippe Abstract Study of structure/function relationships constitutes an important field of research, especially for modification of protein function and drug design. However, the fact that rational design (i.e. the modification of amino acid sequences by means of directed mutagenesis, based on knowledge of the three-dimensional structure) appears to be much less efficient than irrational design (i.e. random mutagenesis followed by in vitro selection) clearly indicates that we understand little about the relationships between primary sequence, three-dimensional structure and function. The use of evolutionary approaches and concepts will bring insights to this difficult question. The increasing availability of multigene family sequences that has resulted from genome projects has inspired the creation of novel in silico evolutionary methods to predict details of protein function in duplicated (paralogous) proteins. The underlying principle of all such approaches is to compare the evolutionary properties of homologous sequence positions in paralogs. It has been proposed that the positions that show switches in substitution rate over time--i.e., 'heterotachous sites'--are good indicators of functional divergence. However, it appears that heterotachy is a much more general process, since most variable sites of homologous proteins with no evidence of functional shift are heterotachous. Similarly, it appears that switches in substitution rate are as frequent when paralogous sequences are compared as when orthologous sequences are compared. Heterotachy, instead of being indicative of functional shift, may more generally reflect a less specific process related to the many intra- and inter-molecular interactions compatible with a range of more or less equally viable protein conformations. These interactions will lead to different constraints on the nature of the primary sequences, consistently with theories suggesting the non-independence of substitutions in proteins. However, a specific type of amino acid variation might constitute a good indicator of functional divergence: substitutions occurring at positions that are generally slowly evolving. Such substitutions at constrained sites are indeed much more frequent soon after gene duplication. The identification and analysis of these sites by complementing structural information with evolutionary data may represent a promising direction to future studies dealing with the functional characterization of an ever increasing number of multi-gene families identified by complete genome analysis. IUBMB Life, 55: 257-265, 2003 [source] MICROFINANCE REVOLUTION: ITS EFFECTS, INNOVATIONS, AND CHALLENGESTHE DEVELOPING ECONOMIES, Issue 1 2010Hisaki KONO F35; O19 "Microfinance revolution" is the term often applied to the successful expansion of small-scale financial services to the poor with high repayment records in developing countries. The present paper investigates the extent to which the microfinance revolution is truly revolutionary. More specifically, it explores the impact of microfinance institutions on the poor, the mechanisms underlying high repayment rates and their innovations, and the new challenges microfinance institutions are currently facing. Different from the existing published survey literature, we focus on current topics and attempt to show recent theoretical developments in a comprehensive manner using simplified models with very similar settings. We contend that microfinance is developing in a promising direction but has yet to reach its full potential. [source] Development and Validation of Small-diameter Vascular Tissue From a Decellularized Scaffold Coated With Heparin and Vascular Endothelial Growth FactorARTIFICIAL ORGANS, Issue 3 2009Min Zhou Abstract To overcome shortcomings of current small-diameter vascular prostheses, we developed a novel allogenic vascular graft from a decellularized scaffold modified through heparin immobilization and vascular endothelial growth factor (VEGF) coating. The VEGF coating and release profiles were assayed by enzyme-linked immunosorbent assay, the biological activity of modified surface was validated by human umbilical vein endothelial cells seeding and proliferation for 10 days in vitro. In vivo, we implanted either a modified or a nonmodified scaffold as bilateral carotid allogenic graft in canines (n = 15). The morphological examination of decellularized scaffolds showed complete removal of cellular components while the extracellular matrix structure remained intact. After modification, the scaffolds possessed local sustained release of VEGF up to 20 days, on which the cells cultured showed significantly higher proliferation rate throughout the time after incubation compared with the cells cultured on nonmodified scaffolds (P < 0.0001). After 6 months of implantation, the luminal surfaces of modified scaffolds exhibited complete endothelium regeneration, however, only a few disorderly cells and thrombosis overlay the luminal surfaces of nonmodified scaffolds. Specifically, the modified scaffolds exhibited significantly smaller hyperplastic neointima area compared with the nonmodified, not only at midportion (0.56 ± 0.07 vs. 2.04 ± 0.12 mm2, P < 0.0001), but also at anastomotic sites (1.76 ± 0.12 vs. 3.67 ± 0.20 mm2, P < 0.0001). Moreover, modified scaffolds had a significantly higher patency rate than the nonmodified after 6 months of implantation (14/15 vs. 7/15, P = 0.005). Overall, this modified decellularized scaffold provides a promising direction for fabrication of small-diameter vascular grafts. [source] The FRIENDS platform,A software platform for advanced services and applicationsBELL LABS TECHNICAL JOURNAL, Issue 3 2000Hendrik B. Meeuwissen New high-speed networks provide new opportunities for service providers to offer advanced voice, data, and multimedia services. This paper describes an extendible framework for the efficient creation and deployment of services. The framework integrates the needs of service providers, service developers, and end users within a single coherent architecture. In this architecture, services are composed of distributed software components. The framework provides the infrastructure for component interaction and encourages reuse of service logic from a rich set of basic components. This paper describes details of both the infrastructure and the components that implement the reusable service logic. The application of the service framework is illustrated by a case study of a multi-party service for collaborative work in project teams. The integration of the service framework and the Lucent Softswitch is a promising direction for future research. [source] Stabilization of organic matter in temperate soils: mechanisms and their relevance under different soil conditions , a reviewEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2006M. v. Lützow Summary Mechanisms for C stabilization in soils have received much interest recently due to their relevance in the global C cycle. Here we review the mechanisms that are currently, but often contradictorily or inconsistently, considered to contribute to organic matter (OM) protection against decomposition in temperate soils: (i) selective preservation due to recalcitrance of OM, including plant litter, rhizodeposits, microbial products, humic polymers, and charred OM; (ii) spatial inaccessibility of OM against decomposer organisms due to occlusion, intercalation, hydrophobicity and encapsulation; and (iii) stabilization by interaction with mineral surfaces (Fe-, Al-, Mn-oxides, phyllosilicates) and metal ions. Our goal is to assess the relevance of these mechanisms to the formation of soil OM during different stages of decomposition and under different soil conditions. The view that OM stabilization is dominated by the selective preservation of recalcitrant organic components that accumulate in proportion to their chemical properties can no longer be accepted. In contrast, our analysis of mechanisms shows that: (i) the soil biotic community is able to disintegrate any OM of natural origin; (ii) molecular recalcitrance of OM is relative, rather than absolute; (iii) recalcitrance is only important during early decomposition and in active surface soils; while (iv) during late decomposition and in the subsoil, the relevance of spatial inaccessibility and organo-mineral interactions for SOM stabilization increases. We conclude that major difficulties in the understanding and prediction of SOM dynamics originate from the simultaneous operation of several mechanisms. We discuss knowledge gaps and promising directions of future research. [source] Serving God and Country?JOURNAL FOR THE SCIENTIFIC STUDY OF RELIGION, Issue 4 2009Military Service Among Young Adult Men, Religious Involvement Despite important connections between religion and military action throughout world history, scholars have seldom explored the association between religiosity and military enlistment. Using data from the National Longitudinal Study of Adolescent Health (Add Health), we used a person-oriented analysis to categorize young men according to patterns of adolescent religious involvement. Youth indentified as "highly religious evangelical" are more likely to enlist in the military compared to their "highly religious nonevangelical" and "nonreligious" counterparts; however, these findings hold only for those young men without college experience. These findings are discussed along with study limitations and promising directions for future research. [source] Size, Conflict, and Opportunities for Interaction: Congregational Effects on Members' Anticipated Support and Negative InteractionJOURNAL FOR THE SCIENTIFIC STUDY OF RELIGION, Issue 1 2009Christopher G. Ellison A growing literature examines the role of religious communities as sources of social support for members, and a smaller body of work also explores negative aspects of social relations within congregations. However, very little is known about the characteristics of religious groups that promote or impede the development of supportive networks. We use data from a unique source,the National Congregations Study, linked with individual records from the 1998 General Social Survey (GSS),to explore this issue. Key findings reveal that: (1) individuals who attend very large churches tend to report lower levels of anticipated support and informal negative interaction; (2) the presence of major congregational conflict tends to dampen anticipated support and increase informal negative interaction; and (3) the absence of a well-defined period for informal socializing before or after the worship service is associated with lower levels of anticipated support, but is unrelated to the frequency of negative interaction among church members. Several implications and promising directions for future research are discussed. [source] Sex differences in behaviour as an indirect consequence of mating systemJOURNAL OF FISH BIOLOGY, Issue 4 2000A. E. Magurran A considerable literature has been devoted to documenting differences between the sexes. However, relatively little attention has hitherto been directed towards those differences that arise as an indirect consequence of mating system even though they can have profound implications for the daily lives of the animals involved. In this review we focus on differences in the non-reproductive behaviour of fish and relate these to sexual dimorphism in size and morphology, and to variance in fitness between the sexes. In line with our expectation, differences in distributional ecology, schooling, aggression, predator avoidance and foraging are exaggerated in sexually dimorphic species and polygamous mating systems. Nonetheless, the behaviour of males and females may also differ in sexually monomorphic and monogamous species. We conclude by highlighting promising directions for further research. [source] Pharmacologic Treatments for Heroin and Cocaine DependenceTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 2003Herbert D. Kleber M.D. Given the difficulty of achieving sustained recovery, pharmacotherapy of opioid and cocaine addiction is more effective when combined with behavioral and psychosocial approaches. Effective pharmacotherapies for opioid dependence and withdrawal include methadone, L-alpha acetylmethadol (LAAM), naltrexone, buprenorphine, and clonidine. Treatment of cocaine addiction includes anti-craving agents, dopamine agonists or blocking agents, antidepressants, and treatment of co-morbid psychiatric disorders, but all with mixed results. In this paper, we discuss the use of medication in the context of general principles of opioid and cocaine addiction treatment. Both established medications and promising directions in pharmacotherapy will be addressed. [source] The life and death of gene familiesBIOESSAYS, Issue 1 2009Jeffery P. Demuth Abstract One of the unique insights provided by the growing number of fully sequenced genomes is the pervasiveness of gene duplication and gene loss. Indeed, several metrics now suggest that rates of gene birth and death per gene are only 10,40% lower than nucleotide substitutions per site, and that per nucleotide, the consequent lineage-specific expansion and contraction of gene families may play at least as large a role in adaptation as changes in orthologous sequences. While gene family evolution is pervasive, it may be especially important in our own evolution since it appears that the "revolving door" of gene duplication and loss has undergone multiple accelerations in the lineage leading to humans. In this paper, we review current understanding of gene family evolution including: methods for inferring copy number change, evidence for adaptive expansion and adaptive contraction of gene families, the origins of new families and deaths of previously established ones, and finally we conclude with a perspective on challenges and promising directions for future research. [source] Binase and other microbial RNases as potential anticancer agentsBIOESSAYS, Issue 8 2008Alexander A. Makarov Some RNases possess preferential cytotoxicity against malignant cells. The best known of these RNases, onconase, was isolated from frog oocytes and is in clinical trials as anticancer therapy. Here we propose an alternative platform for anticancer therapy based on T1 RNases of microbial origin, in particular binase from Bacillus intermedius and RNase Sa from Streptomyces aureofaciens. We discuss their advantages and the most promising directions of research for their potential clinical applications. BioEssays 30:781,790, 2008. © 2008 Wiley Periodicals, Inc. [source] Improved survival time: What can survival cure models tell us about population-based survival improvements in late-stage colorectal, ovarian, and testicular cancer?,CANCER, Issue 10 2008Lan Huang PhD Abstract BACKGROUND The objective of the current study was to investigate the long-term impact of treatment advances on the survival of patients with late-stage ovarian, colorectal (American Joint Committee on Cancer stage III, men), and testicular cancers by estimating the increase in the percentage cured from their disease and the change in survival time of uncured patients. METHODS Cause-specific survival data from 1973 to 2000 were obtained from the Surveillance, Epidemiology, and End Results Program. Survival cure models were fit and were used to estimate the gain in life expectancy (GLE) attributed to an increase in the fraction of cured patients and to prolonged survival among noncured patients. RESULTS Treatment improvement for ovarian cancer resulted in a total GLE of 2 years, and 80% of that GLE was because of an extension of survival time in uncured patients (from 0.9 years to 2.1 years) rather than an increased cure fraction (from 12% to 14%). In contrast, the cure rate rose from 29% to 47% for colorectal cancer, representing 82% of a 2.8-year GLE, and from 23% to 81% for testicular cancer, representing 100% of a 24-year GLE. CONCLUSIONS The current results suggested that treatment benefits for testicular and colorectal cancer in men with late-stage disease primarily are the result of increases in cure fraction, whereas survival gains for ovarian cancer occur despite persisting disease. Cure models, in combination with population-level data, provide insight into how treatment advances are changing survival and ultimately impacting mortality. Survival patterns reflect the underlying biology of response to cancer treatment and suggest promising directions for future research. Cancer 2008. Published 2008 by the American Cancer Society. [source] | |||||||||||||||||||