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Broad Application (broad + application)
Selected AbstractsA Novel Class of P,O Monophosphite Ligands Derived from D-Mannitol: Broad Applications in Highly Enantioselective Rh-Catalyzed Hydrogenations.CHEMINFORM, Issue 32 2004Hanmin Huang Abstract For Abstract see ChemInform Abstract in Full Text. [source] Modelling species distributions without using species distributions: the cane toad in Australia under current and future climatesECOGRAPHY, Issue 4 2008Michael Kearney Accurate predictions of the potential distribution of range-shifting species are required for effective management of invasive species, and for assessments of the impact of climate change on native species. Range-shifting species pose a challenge for traditional correlative approaches to range prediction, often requiring the extrapolation of complex statistical associations into novel environmental space. Here we take an alternative approach that does not use species occurrence data, but instead captures the fundamental niche of a species by mechanistically linking key organismal traits with spatial data using biophysical models. We demonstrate this approach with a major invasive species, the cane toad Bufo marinus in Australia, assessing the direct climatic constraints on its ability to move, survive, and reproduce. We show that the current range can be explained by thermal constraints on the locomotor potential of the adult stage together with limitations on the availability of water for the larval stage. Our analysis provides a framework for biologically grounded predictions of the potential for cane toads to expand their range under current and future climate scenarios. More generally, by quantifying spatial variation in physiological constraints on an organism, trait-based approaches can be used to investigate the range-limits of any species. Assessments of spatial variation in the physiological constraints on an organism may also provide a mechanistic basis for forecasting the rate of range expansion and for understanding a species' potential to evolve at range-edges. Mechanistic approaches thus have broad application to process-based ecological and evolutionary models of range-shift. [source] Sensors: DNA Sensing Using Nanocrystalline Surface-Enhanced Al2O3 Nanopore Sensors (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 8 2010Mater. R. Bashir and co-workers report on page 1266 the development of solid-state Al2O3 nanopore sensors with enhanced surface properties for the real-time detection and analysis of individual DNA molecules. The cover illustrates the extension of coiled double-stranded DNA in the high-field region surrounding a nanocrystalline Al2O3 nanopore, followed by DNA transport. Nanocrystallite nucleation during pore formation helps enhance the single-molecule sensitivity and surface-charge characteristics of these devices and enables the potential fabrication of nanometer-scale metallic contacts in the pore. This technology finds broad application in drug screening, medicine, and bio-nanotechnology. [source] Using disease risk estimates to guide risk factor interventions: field test of a patient workbook for self-assessing coronary riskHEALTH EXPECTATIONS, Issue 1 2002J. Michael Paterson MSc Objective,To assess the feasibility and acceptability of a patient workbook for self-assessing coronary risk. Design,Pilot study, with post-study physician and patient interviews. Setting and subjects,Twenty southern Ontario family doctors and 40 patients for whom they would have used the workbook under normal practice conditions. Interventions,The study involved convening two sequential groups of family physicians: the first (n=10) attended focus group meetings to help develop the workbook (using algorithms from the Framingham Heart Study); the second (n=20) used the workbook in practice with 40 patients. Follow-up interviews were by interviewer-administered questionnaire. Main outcome measures,Physicians' and patients' opinions of the workbook's format, content, helpfulness, feasibility, and potential for broad application, as well as patients' perceived 10-year risk of a coronary event measured before and after using the workbook. Results,It took an average of 18 minutes of physician time to use the workbook: roughly 7 minutes to introduce it to patients, and about 11 minutes to discuss the results. Assessments of the workbook were generally favourable. Most patients were able to complete it on their own (78%), felt they had learned something (80%) and were willing to recommend it to someone else (98%). Similarly, 19 of 20 physicians found it helpful and would use it in practice with an average of 18% of their patients (range: 1,80%). The workbook helped to correct misperceptions patients had about their personal risk of a coronary event over the next 10 years (pre-workbook (mean (SD) %): 35.2 (16.9) vs. post-workbook: 17.3 (13.5), P < 0.0001; estimate according to algorithm: 10.6 (7.6)). Conclusions,Given a simple tool, patients can and will assess their own risk of CHD. Such tools could help inform otherwise healthy individuals that their risk is increased, allowing them to make more informed decisions about their behaviours and treatment. [source] Highly Sensitive, Mechanically Stable Nanopore Sensors for DNA AnalysisADVANCED MATERIALS, Issue 27 2009Bala Murali Venkatesan Highly sensitive, mechanically robust Al2O3 nanopores are fabricated and characterized. These sensors allow for size control with sub-nanometer precision, chemical modification, and exhibit superior noise performance and increased lifetime over their solid-state counterparts. This new class of nanopore sensor is used in dsDNA studies and finds broad application in bio-nanotechnology. [source] Biomedical Applications of Layer-by-Layer Assembly: From Biomimetics to Tissue Engineering,ADVANCED MATERIALS, Issue 24 2006Z. Tang Abstract The design of advanced, nanostructured materials at the molecular level is of tremendous interest for the scientific and engineering communities because of the broad application of these materials in the biomedical field. Among the available techniques, the layer-by-layer assembly method introduced by Decher and co-workers in 1992 has attracted extensive attention because it possesses extraordinary advantages for biomedical applications: ease of preparation, versatility, capability of incorporating high loadings of different types of biomolecules in the films, fine control over the materials' structure, and robustness of the products under ambient and physiological conditions. In this context, a systematic review of current research on biomedical applications of layer-by-layer assembly is presented. The structure and bioactivity of biomolecules in thin films fabricated by layer-by-layer assembly are introduced. The applications of layer-by-layer assembly in biomimetics, biosensors, drug delivery, protein and cell adhesion, mediation of cellular functions, and implantable materials are addressed. Future developments in the field of biomedical applications of layer-by-layer assembly are also discussed. [source] Intolerable human suffering and the role of the ancestor: literary criticism as a means of analysisJOURNAL OF ADVANCED NURSING, Issue 3 2000Elizabeth Harrison RN PhD Intolerable human suffering and the role of the ancestor: literary criticism as a means of analysis This essay explores the experience of intolerable human suffering in Toni Cade Bambara's novel, The Salt Eaters. The method of analysis is literary criticism, a technique that shares many of the same goals as other types of inquiry. It employs close reading to illuminate the novel's meaning(s), thereby revealing information about the nature of intolerable human suffering. Morrison's characteristics of black art is the literary and cultural framework that guides the analysis of Bambara's novel. The paradigm has broad application for nursing. The purpose of this analysis was to describe the role of the ancestral system as a predictor of the trajectory of suffering. The results extend Morrison's paradigm and her notion of ancestor to include traditions and other non-corporeal factors that are essential for well-being and survival. The protagonist in Bambara's novel, Velma Henry, is the patient and exemplar who does not succumb to intolerable suffering because of its cumulative weight, but because she has lost touch with the traditions of her people, an essential component of her ancestral system. The ancestral system is a rich and complex network of individuals, groups, customs and beliefs that are instructive, protective and benevolent. Ancestors are also timeless and provide wisdom, but when the ancestral system is weak or absent, the trajectory of suffering is not favourable. Nurses must learn to recognize intolerable human suffering, to identify the patient's ancestral system, and to work within that system to keep suffering patients from harm. [source] Linking resources with demography to understand resource limitation for bearsJOURNAL OF APPLIED ECOLOGY, Issue 6 2007MELISSA J. REYNOLDS-HOGLAND Summary 1,Identifying the resources that limit growth of animal populations is essential for effective conservation; however, resource limitation is difficult to quantify. Recent advances in geographical information systems (GIS) and resource modelling can be combined with demographic modelling to yield insights into resource limitation. 2,Using long-term data on a population of black bears Ursus americanus, we evaluated competing hypotheses about whether availability of hard mast (acorns and nuts) or soft mast (fleshy fruits) limited bears in the southern Appalachians, USA, during 1981,2002. The effects of clearcutting on habitat quality were also evaluated. Annual survival, recruitment and population growth rate were estimated using capture,recapture data from 101 females. The availability of hard mast, soft mast and clearcuts was estimated with a GIS, as each changed through time as a result of harvest and succession, and then availabilities were incorporated as covariates for each demographic parameter. 3,The model with the additive availability of hard mast and soft mast across the landscape predicted survival and population growth rate. Availability of young clearcuts predicted recruitment, but not population growth or survival. 4,Availability of hard mast stands across the landscape and availability of soft mast across the landscape were more important than hard mast production and availability of soft mast in young clearcuts, respectively. 5,Synthesis and applications. Our results indicate that older stands, which support high levels of hard mast and moderate levels of soft mast, should be maintained to sustain population growth of bears in the southern Appalachians. Simultaneously, the acreage of intermediate aged stands (10,25 years), which support very low levels of both hard mast and soft mast, should be minimized. The approach used in this study has broad application for wildlife management and conservation. State and federal wildlife agencies often possess long-term data on both resource availability and capture,recapture for wild populations. Combined, these two data types can be used to estimate survival, recruitment, population growth, elasticities of vital rates and the effects of resource availability on demographic parameters. Hence data that are traditionally used to understand population trends can be used to evaluate how and why demography changes over time. [source] Oligohis-tags: mechanisms of binding to Ni2+ -NTA surfacesJOURNAL OF MOLECULAR RECOGNITION, Issue 4 2009Steven Knecht Abstract Since immobilized metal ion affinity chromatography (IMAC) was first reported, several modifications have been developed. Among them, Ni2+ immobilized by chelation with nitrilotriacetic acid (NTA) bound to a solid support has become the most common method for the purification of proteins carrying either a C - or N -terminal histidine (His) tag. Despite its broad application in protein purification, only little is known about the binding properties of the His-tag, and therefore almost no thermodynamic and kinetic data are available. In this study, we investigated the binding mechanism of His-tags to Ni2+ -NTA. Different series of oligohistidines and mixed oligohistidines/oligoalanines were synthesized using automated solid-phase peptide synthesis (SPPS). Binding to Ni2+ -NTA was analyzed both qualitatively and quantitatively with surface plasmon resonance (SPR) using commercially available NTA sensor chips from Biacore. The hexahistidine tag shows an apparent equilibrium dissociation constant (KD) of 14,±,1,nM and thus the highest affinity of the peptides synthesized in this study. Furthermore, we could demonstrate that two His separated by either one or four residues are the preferred binding motifs within hexahis tag. Finally, elongation of these referred motifs decreased affinity, probably due to increased entropy costs upon binding. Copyright © 2009 John Wiley & Sons, Ltd. [source] NLPIR: A theoretical framework for applying natural language processing to information retrievalJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 2 2003Lina Zhou The role of information retrieval (IR) in support of decision making and knowledge management has become increasingly significant. Confronted by various problems in traditional keyword-based IR, many researchers have been investigating the potential of natural language processing (NLP) technologies. Despite widespread application of NLP in IR and high expectations that NLP can address the problems of traditional IR, research and development of an NLP component for an IR system still lacks support and guidance from a cohesive framework. In this paper, we propose a theoretical framework called NLPIR that aims at integrating NLP into IR and at generalizing broad application of NLP in IR. Some existing NLP techniques are described to validate the framework, which not only can be applied to current research, but is also envisioned to support future research and development in IR that involve NLP. [source] Unsupervised classification methods in food sciences: discussion and outlookJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2008Marcin Kozak Abstract This paper reviews three unsupervised multivariate classification methods: principal component analysis, principal component similarity analysis and heuristic cluster analysis. The theoretical basis of each method is presented in brief, and assumptions inherent to the methods are highlighted. A literature review shows that these methods have sometimes been used inappropriately or without referencing all essential parameters. The paper also brings to the attention of the reader a relatively unknown method: probabilistic or model-based cluster analysis. The goal of this method is to uncover the true classification of objects rather than a convenient classification provided by the other methods. For this reason it is felt that model-based cluster analysis will have broad application in the future. Copyright © 2008 Society of Chemical Industry [source] Legal Accountability in the Service-Based Welfare State: Lessons from Child Welfare ReformLAW & SOCIAL INQUIRY, Issue 3 2009Kathleen G. Noonan Current trends intensify the longstanding problem of how the rule of law should be institutionalized in the welfare state. Welfare programs are being redesigned to increase their capacities to adapt to rapidly changing conditions and to tailor their responses to diverse clienteles. These developments challenge the understanding of legal accountability developed in the Warren Court era. This article reports on an emerging model of accountable administration that strives to reconcile programmatic flexibility with rule-of-law values. The model has been developed in the reform of state child protective services systems, but it has potentially broad application to public law. It also has novel implications for such basic rule-of-law issues as the choice between rules and standards, the relation of bureaucratic and judicial control, the proper scope of judicial intervention into dysfunctional public agencies, and the justiciability of "positive" (or social and economic) rights. [source] Gene expression normalization in a dual-compartment system: a real-time quantitative polymerase chain reaction protocol for symbiotic anthozoansMOLECULAR ECOLOGY RESOURCES, Issue 2 2009ANDERSON B. MAYFIELD Abstract Traditional real-time quantitative polymerase chain reaction protocols cannot be used accurately with symbiotic organisms unless the relative contribution of each symbiotic compartment to the total nucleic acid pool is known. A modified ,universal reference gene' protocol was created for reef-building corals and sea anemones, anthozoans that harbour endosymbiotic dinoflagellates belonging to the genus Symbiodinium. Gene expression values are first normalized to an RNA spike and then to a symbiont molecular proxy that represents the number of Symbiodinium cells extracted and present in the RNA. The latter is quantified using the number of genome copies of heat shock protein-70 (HSP70) amplified in the real-time quantitative polymerase chain reaction. Gene expression values are then normalized to the total concentration of RNA to account for differences in the amount of live tissue extracted among experimental treatments and replicates. The molecular quantification of symbiont cells and effect of increasing symbiont contributions to the nucleic acid pool on gene expression were tested in vivo using differentially infected sea anemones Aiptasia pulchella. This protocol has broad application to researchers who seek to measure gene expression in mixed organism assemblages. [source] Frozen in time: a new method using cryo-scanning electron microscopy to visualize root,fungal interactionsNEW PHYTOLOGIST, Issue 2 2006Steve Refshauge Summary ,,A new method of sample preparation for cryo-scanning electron microscopy was used to visualize internal infection of wheat (Triticum aestivum) roots by the pathogenic fungus Rhizoctonia solani AG-8. The new method retained fungal hyphae and root cells in situ in disintegrating root tissues, thus avoiding the distortions that can be introduced by conventional preparation by chemical fixation, dehydration and embedding. ,,Infected roots frozen in liquid nitrogen were cryo-planed and etched (sublimed) at ,80°C for a critical length of time (up to 9 min) in the microscope column to reveal plant and fungal structures in three dimensions. ,,Root and fungal structures were well preserved irrespective of infection severity. Root and hyphal cell walls were clearly seen and hyphal architecture within and between root cells was preserved. ,,This rapid method permits three-dimensional in situ visualization of fungal invasion within roots and has broad application for examination of diseases caused by other necrotrophic fungi. [source] A comprehensive framework for the evaluation of metacommunity structureOIKOS, Issue 6 2010Steven J. Presley The metacommunity framework is a powerful platform for evaluating patterns of species distribution in geographic or environmental space. Idealized patterns (checkerboard, Clementsian, evenly spaced, Gleasonian and nested distributions) give the framework shape. Each pattern represents an area in a multidimensional continuum of metacommunity structures; however, the current approach to analysis of spatial structure of metacommunities is incomplete. To address this, we describe additional non-random structures and illustrate how they may be discerned via objective criteria. First, we distinguish three distinct forms of species loss in nested structures, which should improve identification of structuring mechanisms for nested patterns. Second, we define six quasi-structures that are consistent with the conceptual underpinnings of Clementsian, Gleasonian, evenly spaced and nested distributions. Finally, we demonstrate how combinations of structures at smaller spatial extents may aggregate to form Clementsian structure at larger extents. These refinements should facilitate the identification of best-fit patterns, associated structuring mechanisms, and informative scales of analysis and interpretation. This conceptual and analytical framework may be applied to network properties within communities (i.e. structure of interspecific interactions) and has broad application in ecology and biogeography. [source] Recent Synthetic Applications of Manganese in Organic SynthesisCHEMISTRY - A EUROPEAN JOURNAL, Issue 33 2008Abstract While the organometallic compounds derived from many metals have found a broad application in organic synthesis, the use of organomanganese compounds has only recently been developed due to the passivity exhibited by commercial Mn in the direct metalation of organic compounds. In this Concept article, we highlight the potential of manganese and its organometallic compounds in organic synthesis by illustration of the studies previously reported by others and our laboratory in this field. Based on the transformations reported herein, organomanganese compounds could become important tools in the future of the organic synthesis, due to their high selectivity. [source] The Use of Natural Materials in Nanocarbon SynthesisCHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 11 2009Dang Sheng Su Dr. Abstract Nanomaterials are shifting from laboratory-scale preparation to industrial production. The energy costs and starting materials (feedstock, catalyst, and support) consumed or used in the mass production of nanomaterials are issues that limit their broad application. Natural materials, such as sand, rock, and lava, contain small or trace amounts of metals or metal oxides of nanometer-scale sizes and have been recently used as catalysts for the production of carbon nanotubes (CNTs), providing an interesting way to lower the production cost of CNTs. However, the sustainability of the whole production process still needs to be explored. Layered minerals (e.g., clays) are used to produce CNT,clay hybrids, which can be further used to synthesize polymer,CNT,clay nanocomposites. Natural materials and some byproducts of industrial production processes have been explored as carbon sources for nanocarbon synthesis. This Minireview highlights some recent promising work and prospects for the use of natural materials in the synthesis of CNTs, carbon nanofibers (CNFs), and nanocomposites, and their applications in catalysis and in materials science. [source] Mapping cityscapes into cyberspace for visualizationCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 2 2005Jiang Yu Zheng Abstract This work establishes a cyberspace of a real urban area for visiting on the Internet. By registering entire scenes along every street and at many locations, viewers can visually travel around and find their destinations in cyberspace. The issues we discuss here are mapping of a large-scale area to image domains in a small amount of data, and effective display of the captured scenes for various applications. Route Panoramas captured along streets and panoramic views captured at widely opening sites are associated to a city map to provide navigation functions. This paper focuses on the properties of our extended images,route panorama, addressing the archiving process applied to an urban area, an environment developed to transmit image data as streaming media, and display for scene traversing on the WWW in real time. The created cyberspaces of urban areas have broad applications such as city tour, real estate searching, e-commerce, heritage preservation, urban planning and construction, and vehicle navigation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Optimization of a flow cytometry-based protocol for detection and phenotypic characterization of multipotent mesenchymal stromal cells from human bone marrowCYTOMETRY, Issue 6 2006Elena A. Jones Abstract Background: To study the biology of rare bone marrow (BM) multipotent mesenchymal stromal cells (MSCs), recognized protocols are needed. Colony-forming unit-fibroblast (CFU-F) assays have historically been used for the enumeration of MSCs. However, the need to isolate and further analyze MSCs requires new strategies based on cell surface markers. The purpose of this work was to verify the phenotype of BM MSCs in vivo and to develop flow cytometry-based methods for their evaluation. Methods: Pre-enrichment with D7-FIB-conjugated microbeads, cell sorting for CD45lowD7-FIB+LNGFR+ cells, and CFU-F assay were used to confirm the phenotype of BM MSCs in vivo. Further phenotypic characterization of MSCs was performed using three-color flow cytometry following pre-enrichment or by direct four-color flow cytometry. The sensitivity of direct flow cytometry/rare event analysis for the accurate enumeration of MSCs was validated using 85 samples from patients with neoplastic BM diseases. Results: In normal BM, a significant correlation was found between the frequencies of CFU-Fs and CD45lowD7-FIB+LNGFR+ cells (n = 19, R = 0.719, P = 0.001). Following cell sorting, ,15% of these cells were clonogenic. The same cells were enriched using LNGFR-based positive selection, CD45/Glycophorin A-based depletion, or plastic adherence. CD45lowD7-FIB+LNGFR+ cells expressed classic makers of cultured MSCs CD73/SH3 and CD105/SH2 and markers of stromal reticular cells CD106/VCAM and alkaline phosphatase. Novel markers were identified including leukemia inhibitory factor receptor and gp130. CD45lowD7-FIB+LNGFR+ cells were increased fourfold in the floating fat fraction of normal BM aspirates. Their frequency was decreased in chronic lymphocytic leukemia (threefold, n = 13, P = 0.049) and chronic myelogenous leukemia (ninefold, n = 11, P = 0.001) compared with that in age-matched controls (n = 26 and n = 31, respectively). Conclusions: This study demonstrates the usefulness of flow cytometry-based methods for the detection, enumeration and further phenotypic analysis of BM MSCs. These findings have broad applications for the future evaluation of BM MSCs in health and disease. © 2006 International Society for Analytical Cytology [source] Genetically engineered Pseudomonas: a factory of new bioplastics with broad applicationsENVIRONMENTAL MICROBIOLOGY, Issue 10 2001Elías R. Olivera Summary New bioplastics containing aromatic or mixtures of aliphatic and aromatic monomers have been obtained using genetically engineered strains of Pseudomonas putida. The mutation (,) or deletion (,) of some of the genes involved in the ,-oxidation pathway (fadA,, fadB,,fadA or ,fad,BA mutants) elicits a strong intracellular accumulation of unusual homo- or co-polymers that dramatically alter the morphology of these bacteria, as more than 90% of the cytoplasm is occupied by these macromolecules. The introduction of a blockade in the ,-oxidation pathway, or in other related catabolic routes, has allowed the synthesis of polymers other than those accumulated in the wild type (with regard to both monomer size and relative percentage), the accumulation of certain intermediates that are rapidly catabolized in the wild type and the accumulation in the culture broths of end catabolites that, as in the case of phenylacetic acid, phenylbutyric acid, trans -cinnamic acid or their derivatives, have important medical or pharmaceutical applications (antitumoral, analgesic, radiopotentiators, chemopreventive or antihelmintic). Furthermore, using one of these polyesters (poly 3-hydroxy-6-phenylhexanoate), we obtained polymeric microspheres that could be used as drug vehicles. [source] Low doses of bromo- and iododeoxyuridine produce near-saturation labeling of adult proliferative populations in the dentate gyrusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2005Kevin A. Burns Abstract Cell proliferation can be detected by the incorporation of tritiated thymidine (3H-dT) or halopyrimidines during DNA synthesis in progenitor cells. Administration of two thymidine analogues at different times can further determine the cell-cycle kinetics of proliferating cells. Traditionally, this was done by combining bromodeoxyuridine (BrdU) immunocytochemistry and 3H-dT autoradiography, or by BrdU and iododeoxyuridine (IdU) double-labeling using two mouse antibodies. However, these methods either require lengthy exposure time or involve complicated histological procedures for differentiating between two antibodies of the same species. Here we report a simple and reliable method of distinguishing BrdU- and IdU-labeled cells by immunofluorescence. This method uses a mouse monoclonal antibody that recognizes both BrdU and IdU and a rat anti-BrdU antibody that has no cross-reactivity with IdU. When combined with species-specific secondary antibodies that are conjugated to different fluorophores, this method identifies BrdU- and IdU-incorporation as doubly and singly labeled cells, respectively. This method has broad applications. First, we demonstrate that this method can distinguish mouse cortical neurons generated on different embryonic days. Second, by administering IdU and BrdU at varying intervals, we used this method to calculate that the length of S-phase of neural progenitor cells in the adult mouse dentate gyrus is approximately 6 h. Finally, we show that a six-fold higher concentration of IdU detects only 10% more cells than the standard dose of BrdU (50 mg/kg) using the double-labeling method. These results suggest that the standard dose of BrdU is sufficient to label the majority of proliferative populations in the S-phase in pulse labeling experiments. [source] Complex chromosome aberrations persist in individuals many years after occupational exposure to densely ionizing radiation: An mFISH studyGENES, CHROMOSOMES AND CANCER, Issue 1 2005M. Prakash Hande Long-lived, sensitive, and specific biomarkers of particular mutagenic agents are much sought after and potentially have broad applications in the fields of cancer biology, epidemiology, and prevention. Many clastogens induce a spectrum of chromosome aberrations, and some of them can be exploited as biomarkers of exposure. Densely ionizing radiation, for example, alpha particle radiation (from radon or plutonium) and neutron radiation, preferentially induces complex chromosome aberrations, which can be detected by the 24-color multifluor fluorescence in situ hybridization (mFISH) technique. We report the detection and quantification of stable complex chromosome aberrations in lymphocytes of healthy former nuclear-weapons workers, who were exposed many years ago to plutonium, gamma rays, or both, at the Mayak weapons complex in Russia. We analyzed peripheral-blood lymphocytes from these individuals for the presence of persistent complex chromosome aberrations. A significantly elevated frequency of complex chromosome translocations was detected in the highly exposed plutonium workers but not in the group exposed only to high doses of gamma radiation. No such differences were found for simple chromosomal aberrations. The results suggest that stable complex chromosomal translocations represent a long-lived, quantitative, low-background biomarker of densely ionizing radiation for human populations exposed many years ago. © 2005 Wiley-Liss, Inc. [source] Hollow Micro/Nanomaterials with Multilevel Interior StructuresADVANCED MATERIALS, Issue 36 2009Yong Zhao Abstract In this Review, recent achievements in the multilevel interior-structured hollow 0D and 1D micro/nanomaterials are presented and categorized. The 0D multilevel interior-structured micro/nanomaterials are classified into four main interior structural categories that include a macroporous structure, a core-in-hollow-shell structure, a multishell structure, and a multichamber structure. Correspondingly, 1D tubular micro/nanomaterials are of four analogous structures, which are a segmented structure, a wire-in-tube structure, a multiwalled structure, and a multichannel structure. Because of the small sizes and complex interior structures, some special synthetic strategies that are different from routine hollowing methods, are proposed to produce these interior structures. Compared with the same-sized solid or common hollow counterparts, these fantastic multilevel hollow-structured micro/nanomaterials show a good wealth of outstanding properties that enable them broad applications in catalysis, sensors, Li-ion batteries, microreactors, biomedicines, and many others. [source] Extending point pattern analysis for objects of finite size and irregular shapeJOURNAL OF ECOLOGY, Issue 4 2006THORSTEN WIEGAND Summary 1We use a grid- and simulation-based approach to extend point pattern analysis to deal with plants of finite size and irregular shape, and compare the results of our approach with that of the conventional point approximation. The plants are approximated by using an underlying grid and may occupy several adjacent grid cells depending on their size and shape. Null models correspond to that of point pattern analysis but need to be modified to account for the finite size and irregular shape of plants. 2We use a mapped area of a grass-shrub steppe in semi-arid Patagonia, Argentina, to show that the shrub community is essentially randomly structured, but that shrubs facilitate grasses in their immediate neighbourhood. 3The occurrence of this random spatial structure provides important new information on the biology of shrub populations. In general, previous data from semi-arid and arid ecosystems have shown that adult shrubs tend to show over-dispersed patterns, whereas juveniles are clumped. 4We find that the point approximation may produce misleading results (i) if plant size varies greatly, (ii) if the scale of interest is of the same order of magnitude as the size of the plants, and (iii) if the plants of a given pattern are constrained through competition for space by the presence of other plants. The point approximation worked well in all other cases, but usually depicted weaker significant effects than when the size and shape of plants were taken into account. 5Our approach to quantifying small-scale spatial patterns in plant communities has broad applications, including the study of facilitation and competition. Ecologists will be able to use the software available to take advantage of these methods. [source] Prediction of phase equilibria and excess properties for systems with sulfonesAICHE JOURNAL, Issue 2 2003Roland Wittig The group contribution method modified UNIFAC (Dortmund) has become very popular because of its broad applications, and reliable predictions for vapor-liquid equilibria, solid-liquid equilibria, liquid-liquid equilibria, activity coefficients at infinite dilution, azeotropic data and excess enthalpies in a wide temperature range. Therefore, the existing parameter matrix for the modified UNIFAC method is continuously extended with the help of the Dortmund Data Bank and by carrying out systematic measurements. The new main group for sulfones, such as that required to describe systems with the selective solvent sulfolane, is introduced, as well as ten new pairs of group interaction parameters for modified UNIFAC. [source] Assessment of tissue redox status using metabolic responsive contrast agents and magnetic resonance imagingJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 8 2008Fuminori Hyodo Regulation of tissue redox status is important to maintain normal physiological conditions in the living body. Disruption of redox homoeostasis may lead to oxidative stress and can induce many pathological conditions such as cancer, neurological disorders and ageing. Therefore, imaging of tissue redox status could have clinical applications. Redox imaging employing magnetic resonance imaging (MRI) with nitroxides as cell-permeable redox-sensitive contrast agents has been used for non-invasive monitoring of tissue redox status in animal models. The redox imaging applications of nitroxide electron paramagnetic resonance imaging (EPRI) and MRI are reviewed here, with a focus on application of tumour redox status monitoring. While particular emphasis has been placed on differences in the redox status in tumours compared to selected normal tissues, the technique possesses the potential to have broad applications to the study of other disease states, inflammatory processes and other circumstances where oxidative stress is implicated. [source] DNA Microarray Experiments: Biological and Technological AspectsBIOMETRICS, Issue 4 2002Danh V. Nguyen Summary. DNA microarray technologies, such as cDNA and oligonucleotide microarrays, promise to revolutionize biological research and further our understanding of biological processes. Due to the complex nature and sheer amount of data produced from microarray experiments, biologists have sought the collaboration of experts in the analytical sciences, including statisticians, among others. However, the biological and technical intricacies of microarray experiments are not easily accessible to analytical experts. One aim for this review is to provide a bridge to some of the relevant biological and technical aspects involved in microarray experiments. While there is already a large literature on the broad applications of the technology, basic research on the technology itself and studies to understand process variation remain in their infancy. We emphasize the importance of basic research in DNA array technologies to improve the reliability of future experiments. [source] | |||||||||||||||||||||||||