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Two-step Approach (two-step + approach)
Selected AbstractsA spatial model of bird abundance as adjusted for detection probabilityECOGRAPHY, Issue 2 2009P. Marcos Gorresen Modeling the spatial distribution of animals can be complicated by spatial and temporal effects (i.e. spatial autocorrelation and trends in abundance over time) and other factors such as imperfect detection probabilities and observation-related nuisance variables. Recent advances in modeling have demonstrated various approaches that handle most of these factors but which require a degree of sampling effort (e.g. replication) not available to many field studies. We present a two-step approach that addresses these challenges to spatially model species abundance. Habitat, spatial and temporal variables were handled with a Bayesian approach which facilitated modeling hierarchically structured data. Predicted abundance was subsequently adjusted to account for imperfect detection and the area effectively sampled for each species. We provide examples of our modeling approach for two endemic Hawaiian nectarivorous honeycreepers: ,i,iwi Vestiaria coccinea and ,apapane Himatione sanguinea. [source] Reducing complexity in Qualitative Comparative Analysis (QCA): Remote and proximate factors and the consolidation of democracyEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 5 2006CARSTEN Q. SCHNEIDER However, real-world research situations might make the application of fs/QCA difficult in two respects , namely, the complexity of the results and the phenomenon of limited diversity. We suggest a two-step approach as one possibility to mitigate these problems. After introducing the difference between remote and proximate factors, the application of a two-step fs/QCA approach is demonstrated analyzing the causes of the consolidation of democracy. We find that different paths lead to consolidation, but all are characterized by a fit of the institutional mix chosen to the societal context in terms of power dispersion. Hence, we demonstrate that the application of fs/QCA in a two-step manner helps to formulate and test equifinal and conjunctural hypotheses in medium-size N comparative analyses, and thus to contribute to an enhanced understanding of social phenomena. [source] A two-step procedure for constructing confidence intervals of trait loci with application to a rheumatoid arthritis datasetGENETIC EPIDEMIOLOGY, Issue 1 2006Charalampos Papachristou Abstract Preliminary genome screens are usually succeeded by fine mapping analyses focusing on the regions that signal linkage. It is advantageous to reduce the size of the regions where follow-up studies are performed, since this will help better tackle, among other things, the multiplicity adjustment issue associated with them. We describe a two-step approach that uses a confidence set inference procedure as a tool for intermediate mapping (between preliminary genome screening and fine mapping) to further localize disease loci. Apart from the usual Hardy-Weiberg and linkage equilibrium assumptions, the only other assumption of the proposed approach is that each region of interest houses at most one of the disease-contributing loci. Through a simulation study with several two-locus disease models, we demonstrate that our method can isolate the position of trait loci with high accuracy. Application of this two-step procedure to the data from the Arthritis Research Campaign National Repository also led to highly encouraging results. The method not only successfully localized a well-characterized trait contributing locus on chromosome 6, but also placed its position to narrower regions when compared to their LOD support interval counterparts based on the same data. Genet. Epidemiol. 30:18,29, 2006. © 2005 Wiley-Liss, Inc. [source] Tunable Nanowrinkles on Shape Memory Polymer SheetsADVANCED MATERIALS, Issue 44 2009Chi-Cheng Fu Controllable biaxial and uniaxial nanowrinkles (see figure) are fabricated by a simple two-step approach , metal deposition and subsequent heating , based on shape memory polymer (prestressed polystyrene) sheets. The wavelengths of the wrinkles can be tuned by controlling the thickness of deposited metal. The ready integration of the nanowrinkles into microchannels and their effectiveness in surface enhanced sensing is demonstrated. [source] Oral hygiene care for residents with dementia: a literature reviewJOURNAL OF ADVANCED NURSING, Issue 4 2005Jane Chalmers MS PhD Aim., This paper presents a literature review of oral hygiene care for adults with dementia in residential aged care facilities, including evidence for: (1) prevalence, incidence, experiences and increments of oral diseases; (2) use of assessment tools to evaluate residents' oral health; (3) preventive oral hygiene care strategies; and (4) provision of dental treatment. Background., The impact of dementia on residential care is ever-increasing and regular oral hygiene care provision is challenging for cognitively impaired residents. Although an abundance of oral hygiene care recommendations for older people have been published, the supporting evidence has not been clearly delineated. Methods., A review was conducted of English language publications (1980,2002), using a two-step approach (keyword electronic database search, supplemented with secondary search of cited references). All 306 selected articles were critically reviewed and systematically categorized. Results., Evidence confirmed clinicians' observations of poor oral health in older residents with dementia. Possible risk factors identified were: salivary dysfunction, polypharmacy, medical conditions, swallowing and dietary problems, functional dependence, oral hygiene care assistance and poor use of dental care. One comprehensive, reliable and validated oral assessment screening tool for residents with dementia had been published. Expert opinion indicated that oral assessment screening by staff and a dentist would be ideal at admission and regularly thereafter. Clinicians and researchers suggested that oral hygiene care strategies were effective in preventing oral diseases and appropriate for residents with dementia. Conclusion., These literature review findings supported the use of oral assessment screening tools by staff and efficacious preventive oral hygiene care strategies/products for adults with dementia in residential care facilities. Further research with this population is needed to develop and validate oral assessment tools and staff education programmes, trial preventive oral hygiene care strategies/products and trial dementia-focused behaviour management and communication strategies. [source] Influence of melt drawing on the morphology of one- and two-step processed LDPE/thermoplastic starch blendsADVANCES IN POLYMER TECHNOLOGY, Issue 4 2003F. J. Rodriguez-Gonzalez Abstract In this study the morphology of LDPE/TPS blends prepared by a one-step extrusion process is compared to that obtained by reprocessing of the original blends. The influence of composition and melt drawing is examined. A novel methodology based on the form factor of the dispersed particle was used to estimate the equivalent spherical particle size of dispersed thermoplastic starch (TPS). This approach allows for the quantitative comparison of average dispersed phase particles regardless of their shape. Blends prepared in the one-step extrusion process show increased levels of anisotropy as a consequence of a combination of coalescence and particle deformation during melt drawing. Reprocessed materials demonstrate morphologies that are highly stable to a wide range of hot stretch ratio conditions. The TPS particles of reprocessed blends show no coalescence and a low degree of deformation. This phenomenon is explained by plasticizer evaporation resulting from the second processing step. The TPS is transformed from a highly deformable phase to one resembling a partially cross-linked material. These data indicate that the one-step processing of LDPE/TPS blends can be used to generate a wide range of highly elongated morphological structures. A two-step approach, analogous to typical compounding and shaping operations and involving controlled glycerol removal in the second step can be used to prepare a wide range of highly stable, more isotropic, dispersed particle morphologies. © 2003 Wiley Periodicals, Inc. Adv Polym Techn 22: 297,305, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.10057 [source] Two-step radiosynthesis of [18F]N -succinimidyl-4-fluorobenzoate ([18F]SFB)JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 8 2009Matthias Glaser Abstract The acylation reagent [18F]N -succinimidyl-4-fluorobenzoate (18F-SFB) has been prepared using a new two-step approach. The starting material p- [18F]fluorobenzaldehyde (18F-FBA) was obtained by an improved radiosynthesis with a decay-corrected radiochemical yield of 66±6 % (n=3). Reaction of 18F-FBA with (diacetoxyiodine)benzene and N -hydroxysuccinimide and preparative HPLC purification furnished 18F-SFB in an r.c.y. of 49±6 % (n=3), based on the starting radioactivity of 18F-FBA. The radiochemical purity of 18F-SFB was >99%. Alternatively, purification by solid phase extraction gave 18F-SFB with an r.c.y. of 77±9% (n=4) and a radiochemical purity of 89±5% (n=4). This radiochemical synthesis only used non-aqueous solvents, which simplifies the method and facilitates subsequent applications of 18F-SFB. Copyright © 2009 John Wiley & Sons, Ltd. [source] Ferrocenyl-functionalized long chain branched polydienesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2009Frederik Wurm Abstract A convenient two-step approach for the synthesis of ferrocenyl-functionalized long chain branched polydienes, based on both butadiene and isoprene, respectively, is presented. Classical living anionic polymerization was used to synthesize different ABn type poly(diene) macromonomers with moderate molecular weights between 1700 and 3200 g/mol and narrow polydispersity. Quantitative end-capping with chlorodimethylsilane resulted in the desired ABn macromonomer structures. In the ensuing Pt-catalyzed hydrosilylation polyaddition, branched, functionalized polydienes were obtained by a concurrent ABn + AR type of copolymerization with mono- and difunctional ferrocenyl silanes (fcSiMe2H or fc2SiMeH). Molecular weights of the branched polymers were in the range of 10,000 to 44,000 g/mol (SEC/MALLS). Because of the large number of functional end groups, high loading with ferrocene units up to 63 wt % of ferrocene was achieved. Detailed studies showed full conversion of the functional silanes and incorporation into the branched polymer. Further studies using DSC, TGA, and cyclovoltammetry (CV) measurements have been performed. Electrochemical studies demonstrated different electrochemical properties for fcSiMe2 - and fc2SiMe-units. The CVs of polymers modified with diferrocenylsilane units exhibit the pattern of communicating ferrocenyl sites with two distinct, separate oxidation waves. The polymers were also deposited on an electrode surface and the electrodes investigated via CV, showing formation of electroactive films with promising results for the use of the materials in biosensors. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2518,2529, 2009 [source] Decomposing Product Innovativeness and Its Effects on New Product SuccessTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 5 2006Roger J. Calantone Does product innovativeness affect new product success? The current research proposes that the ambiguity in findings may be due to an overly holistic conceptualization of product innovativeness that has erroneously included the concepts of product advantage and customer familiarity. This article illustrates how the same measures have often been used to assess product advantage with product innovativeness and product innovativeness with customer familiarity. These paired overlaps in measurement use are clarified in this research, which decomposes dimensions of product innovativeness along conceptual lines into distinct product innovativeness, product advantage, and customer familiarity constructs. To further support this decomposition, structural equation modeling is used to empirically test the distinctions. The measurement model supports the conceptual separation, and the path model reveals contingent effects of product innovativeness. Although product innovativeness enhances product advantage, a high level of innovativeness reduces customer familiarity, indicating that product innovativeness can be detrimental to new product success if customers are not sufficiently familiar with the nature of the new product and if innovativeness fails to improve product advantage. This exercise in metric development also reveals that after controlling for product advantage and customer familiarity, product innovativeness has no direct effect on new product profitability. This finding has strong implications for firms that mistakenly pursue innovation for its own sake. Consideration of both distribution and technical synergy as driving antecedents demonstrates how firms can still enhance new product success even if an inappropriate level of innovativeness is present. This leads to a simple but powerful two-step approach to bringing highly innovative products to market. First, firms should only emphasize product innovativeness when it relates to the market relevant concepts of product advantage and customer familiarity. Second, existing technical and distribution abilities can be used to enhance product quality and customer understanding. Distribution channels in particular should be exploited to counter customer uncertainty toward newly introduced products. [source] Particle production and nonlinear diffusion in relativistic systemsANNALEN DER PHYSIK, Issue 7 2008G. Wolschin Abstract The short parton production phase in high-energy heavy-ion collisions is treated analytically as a nonlinear diffusion process. The initial buildup of the rapidity density distributions of produced charged hadrons within ,p, 0.25 fm/c occurs in three sources during the colored partonic phase. In a two-step approach, the subsequent diffusion in pseudorapidity space during the interaction time of ,int, 7-10 fm/c (mean duration of the collision) is essentially linear as expressed in the Relativistic Diffusion Model (RDM) which yields excellent agreement with the data at RHIC energies, and allows for predictions at LHC energies. Results for d+Au are discussed in detail. [source] The depth of a group's personality resources: Impacts on group process and group performanceASIAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2004Michael Harris Bond The present study examines the productivity of task groups in relation to the personality resources of its members and its two dimensions of group process: task focus and shared exchange. It is hypothesized that the depth of a group's personality resources impacts upon productivity both directly through the application of its member's personality resources to successful group outputs, and indirectly through the mediating agency of group process variables that also contribute separately to successful group outputs. To test these hypotheses, the performance of 43 groups in a 3-month social psychology class was measured across three course assignments. This averaged performance score was related to the groups' process scores and to their total levels of personality resources measured by a comprehensive personality inventory administered at the beginning of the groups' life. Using multiple regression, we found that a group's performance was predicted by total member intellect, openness (negatively), and emotional stability (negatively). Blocked regression revealed that group intellect exercised a direct effect upon group performance, but that the effects of group openness and group emotional stability on performance were mediated through the group's two group processes of task focus and shared exchange. It is hoped that this demonstration of a two-step approach to studying the impact of group member's personality through its direct effects on group performance and its indirect effect on performance-linked aspects of group process will be extended to other types of personality measures, and to other types of groups addressing different tasks in other cultural settings. [source] ChemInform Abstract: An Efficient Method for the Synthesis of Unsymmetrical 2,2,-Bis(pyrrolyl)alkanes.CHEMINFORM, Issue 38 2010Marie Laure Murat-Onana Abstract A novel two-step approach towards unsymmetrical bis(pyrrolyl)alkanes is presented. [source] A phylogeny of Vetigastropoda and other "archaeogastropods": re-organizing old gastropod cladesINVERTEBRATE BIOLOGY, Issue 3 2010Stephanie W. Aktipis Abstract. The phylogenetic relationships among the "archaeogastropod" clades Patellogastropoda, Vetigastropoda, Neritimorpha, and Neomphalina are uncertain; the phylogenetic placement of these clades varies across different analyses, and particularly among those using morphological characteristics and those relying on molecular data. This study explores the relationships among these groups using a combined analysis with seven molecular loci (18S rRNA, 28S rRNA, histone H3, 16S rRNA, cytochrome c oxidase subunit I [COI], myosin heavy-chain type II, and elongation factor-1, [EF-1,]) sequenced for 31 ingroup taxa and eight outgroup taxa. The deep evolutionary splits among these groups have made resolution of stable relationships difficult, and so EF-1, and myosin are used in an attempt to re-examine these ancient radiation events. Three phylogenetic analyses were performed utilizing all seven genes: a single-step direct optimization analysis using parsimony, and two-step approaches using parsimony and maximum likelihood. A single-step direct optimization parsimony analysis was also performed using only five molecular loci (18S rRNA, 28S rRNA, histone H3, 16S rRNA, and COI) in order to determine the utility of EF-1, and myosin in resolving deep relationships. In the likelihood and POY optimal phylogenetic analyses, Gastropoda, Caenogastropoda, Neritimorpha, Neomphalina, and Patellogastropoda were monophyletic. Additionally, Neomphalina and Pleurotomariidae fell outside the remaining vetigastropods, indicating the need for further investigation into the relationship of these groups with other gastropods. [source] | ||||||||||||||||