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Terms modified by Transitional Selected AbstractsKinetic Studies of Mullite Synthesis from Alumina Nanoparticles and a Preceramic PolymerJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2008Flavio Griggio The crystallization kinetics of mullite formation in a diphasic precursor consisting of a silicone resin filled with commercial ,-alumina nanoparticles (15 nm mean particle size, specific surface area of 100 m2/g), heated in air from 1250° to 1350°C, was studied by X-ray diffraction. Transitional ,-alumina and amorphous silica from the pyrolysis of the preceramic polymer exhibited a remarkable reactivity, as demonstrated by a very low incubation time (from 500 s at 1250°C to 20 s at 1350°C), a high mullite yield (about 80 vol%, after 100 s at 1350°C), and a low activation energy for nucleation (677±60 kJ/mol). The activation energy values found were lower than those reported previously for other diphasic systems, including sol,gel precursors. Besides the high specific surface of nanosized ,-alumina particles, the low energy barrier could be attributed to the highly reactive silica deriving from the oxidation of Si,CH3 bonds in the silicone and to the homogeneous dispersion of the nanosized filler inside the preceramic polymer. Furthermore, the possibility of applying plastic shaping processing methods to the mixture of a preceramic polymer and nanosized filler makes this approach particularly valuable, in comparison, for instance, with sol,gel based alternatives. [source] Human peripheral blood B-cell compartments: A crossroad in B-cell traffic,CYTOMETRY, Issue S1 2010M. Perez-Andres Abstract A relatively high number of different subsets of B-cells are generated through the differentiation of early B-cell precursors into mature B-lymphocytes in the bone marrow (BM) and antigen-triggered maturation of germinal center B-cells into memory B-lymphocytes and plasmablasts in lymphoid tissues. These B-cell subpopulations, which are produced in the BM and lymphoid tissues, recirculate through peripheral blood (PB), into different tissues including mucosa and the BM, where long-living plasma cells produce antibodies. These circulating PB B-cells can be classified according to their maturation stage into i) immature/transitional, ii) naïve, and iii) memory B-lymphocytes, and iv) plasmablasts/plasma cells. Additionally, unique subsets of memory B-lymphocytes and plasmablasts/plasma cells can be identified based on their differential expression of unique Ig-heavy chain isotypes (e.g.: IgM, IgD, IgG, IgA). In the present paper, we review recent data reported in the literature about the distribution, immunophenotypic and functional characteristics of these cell subpopulations, as well as their distribution in PB according to age and seasonal changes. Additional information is also provided in this regard based on the study of a population-based cohort of 600 healthy adults aged from 20 to 80 years, recruited in the Salamanca area in western Spain. Detailed knowledge of the distribution and traffic of B-cell subsets through PB mirrors the immune status of an individual subject and it may also contribute to a better understanding of B-cell disorders related to B-cell biology and homeostasis, such as monoclonal B-cell lymphocytosis (MBL). © 2010 International Clinical Cytometry Society [source] National Adoption of International Accounting Standards: An Institutional PerspectiveCORPORATE GOVERNANCE, Issue 3 2010William Judge ABSTRACT Manuscript Type: Empirical Research Question/Issue: Effective corporate governance requires accurate and reliable financial information. Historically, each nation has developed and pursued its own financial standards; however, as financial markets consolidate into a global market, there is a need for a common set of financial standards. As a result, there is a movement towards harmonization of international financial reporting standards (IFRS) throughout the global economy. While there has been considerable research on the effects of IFRS adoption, there has been relatively little systematic study as to the antecedents of IFRS adoption. Consequently, this study seeks to understand why some economies have quickly embraced IFRS standards while others partially adopt IFRS and still others continue to resist. Research Findings/Results: After controlling for market capitalization and GDP growth, we find that foreign aid, import penetration, and level of education achieved within a national economy are all predictive of the degree to which IFRS standards are adopted across 132 developing, transitional and developed economies. Theoretical/Academic Implications: We found that all three forms of isomorphic pressures (i.e., coercive, mimetic, and normative) are predictive of IFRS adoption. Consequently, institutional theory with its emphasis on legitimacy-seeking by social actors was relatively well supported by our data. This suggests that the IFRS adoption process is driven more by social legitimization pressures, than it is by economic logic. Practitioner/Policy Implications: For policy makers, our findings suggest that the institutional pressures within an economy are the key drivers of IFRS adoption. Consequently, policy makers should seek to influence institutional pressures that thwart and/or enhance adoption of IFRS. For executives of multinational firms, our findings provide insights that can help to explain and predict future IFRS adoption within economies where their foreign subsidiaries operate. This ability could be useful for creating competitive advantages for foreign subsidiaries where IFRS adoption was resisted, or avoiding competitive disadvantages for foreign subsidiaries unfamiliar with IFRS standards. [source] Is There a Place for Virtual Poverty Funds in Pro-Poor Public Spending Reform?DEVELOPMENT POLICY REVIEW, Issue 4 2003Lessons from Uganda's PAF Various developing countries with weak public expenditure management systems are establishing virtual poverty funds (VPFs), drawing on the experience of Uganda's Poverty Action Fund. As a mechanism for tagging and tracking the performance of specific poverty-reducing expenditures in the budget, a VPF can be useful. However, this article argues that such devices should be treated from the outset as transitional, and as part of wider processes of strengthening public expenditure management; otherwise, they can seriously distort public expenditure allocations and management systems, potentially undermining growth. Emphasis needs to be placed on identifying the right balance of expenditures in the entire budget; improving the effectiveness and efficiency of existing allocations; and developing better public-sector policies for promoting pro-poor private sector growth. [source] Cortical radial glial cells in human fetuses: Depth-correlated transformation into astrocytesDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2003Leonardo C. deAzevedo Abstract In the human brain, the transformation of radial glial cells (RGC) into astrocytes has been studied only rarely. In this work, we were interested in studying the morphologic aspects underlying this transformation during the fetal/perinatal period, particularly emphasizing the region-specific glial fiber anatomy in the medial cortex. We have used carbocyanine dyes (DiI/DiA) to identify the RGC transitional forms and glial fiber morphology. Immunocytochemical markers such as vimentin and glial fibrillary acidic protein (GFAP) were also employed to label the radial cells of glial lineage and to reveal the early pattern of astrocyte distribution. Neuronal markers such as neuronal-specific nuclear protein (NeuN) and microtubule-associated protein (MAP-2) were employed to discern whether or not these radial cells could, in fact, be neurons or neuronal precursors. The main findings concern the beginning of RGC transformation showing loss of the ventricular fixation in most cases, followed by transitional figures and the appearance of mature astrocytes. In addition, diverse fiber morphology related to depth within the cortical mantle was clearly demonstrated. We concluded that during the fetal/perinatal period the cerebral cortex is undergoing the final stages of radial neuronal migration, followed by involution of RGC ventricular processes and transformation into astrocytes. None of the transitional or other radial glia were positive for neuronal markers. Furthermore, the differential morphology of RGC fibers according to depth suggests that factors may act locally in the subplate and could have a role in the process of cortical RGC transformation and astrocyte localization. The early pattern of astrocyte distribution is bilaminar, sparing the cortical plate. Few astrocytes (GFAP+) in the upper band could be found with radial processes at anytime. This suggests that astrocytes in the marginal zone could be derived from different precursors than those that differentiate from RGCs during this period. © 2003 Wiley Periodicals, Inc. J Neurobiol 55: 288,298, 2003 [source] Three-dimensional reconstruction of the mucosa from sequential sections of biopsy specimens of patients with ulcerative colitis: Relationship between crypt structure and vascular architectureDIGESTIVE ENDOSCOPY, Issue 2 2004Hiroo Furukawa Background:, In a previous paper, the stereographic reconstruction of the crypt structure of ulcerative colitis using the RATOCK System was described. The relationship between the blood vessels and the crypt structure is the focus of the current paper, using two kinds of tissue staining color in which the color differs. Stereographic images make the relationship between the crypt structure and blood vessel distribution understandable at a glance. Methods:, The methods used here are identical to those described in a previous paper. In the present paper, five cases of ulcerative colitis (UC) are examined. Biopsy specimens were obtained from the diseased, normal, and transitional zones (the area between the normal and diseased zones) from each patient. Three-dimensional reconstruction was created using TRI for Windows (RATOC System Tokyo, Japan) software. In the present paper, two kinds of dyeing method between H&E and monoclonal antibody staining of the tissue was used. It was proven that the distribution of gland and blood vessel is very clear in the 3-D reconstruction shown. Results:, (i) The blood vessels in the normal zones run parallel to the crypt in a regular manner and are almost identical to one another in diameter. (ii) In the transitional and diseased zones, the blood vessels show no clear direction and produce many branches without any apparent order. The blood vessels are, moreover, irregular in diameter. (iii) In short, clear parallelism is lost in both the transitional and diseased zones. Conclusion:, Stereographic reconstruction of endoscopically obtained biopsy specimens of UC-affected tissues makes it possible to understand at a glance the distribution of blood vessels and their relationship to crypts. The relationship of these was clarified by the combined use of two kinds of dyeing method with three-dimensional reconstruction. [source] The use of short-lived radionuclides to quantify transitional bed material transport in a regulated riverEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2007Nira L. Salant Abstract We investigate the use of the short-lived fallout radionuclide beryllium-7 (7Be; t1/2 = 53·4 days) as a tracer of medium and coarse sand (0·25,2 mm), which transitions between transport in suspension and as bed load, and evaluate the effects of impoundment on seasonal and spatial variations in bed sedimentation. We measure 7Be activities in approximately monthly samples from point bar and streambed sediments in one unregulated and one regulated stream. In the regulated stream our sampling spanned an array of flow and management conditions during the annual transition from flood control in the winter and early spring to run-of-the-river operation from late spring to autumn. Sediment stored behind the dam during the winter quickly became depleted in 7Be activity. This resulted in a pulse of ,dead' sediment released when the dam gates were opened in the spring which could be tracked as it moved downstream. Measured average sediment transport velocities (30,80 metres per day (m d,1)) exceed those typically reported for bulk bed load transport and are remarkably constant across varied flow regimes, possibly due to corresponding changes in bed sand fraction. Results also show that the length scale of the downstream impact of dam management on sediment transport is short (c. 1 km); beyond this distance the sediment trapped by the dam is replaced by new sediment from tributaries and other downstream sources. Copyright © 2006 John Wiley & Sons, Ltd. [source] Complex regulation of CCR9 at multiple discrete stages of T,cell developmentEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 1 2006Marc-André Wurbel Dr. Abstract We have conducted a comprehensive assessment of CCR9 expression and function at the important milestone stages of murine thymocyte development. We reveal an unusually complex regulatory pattern, in which CCR9 influences T,cell development at several widely dispersed stages. We find that CCR9 is not expressed within the thymus until the double-negative (DN)3 stage, although it appears to contribute to T,cell precursor development prior to residence in the thymus. CCR9 expression is influenced by pre-T,cell receptor signals, and is dramatically up-regulated in a population that appears to be transitional between the DN4 and double-positive stages. In the periphery, functional CCR9 is expressed by all naive CD8 T,cells, but not by naive CD4 T,cells. To our knowledge, this latter finding is the first difference observed in homing receptor expression between naive lymphocyte populations. This suggests that naive CD8 T,cells might have access to lymphoid microenvironments from which naive CD4 T,cells are excluded. [source] Fiscal Decentralisation and Empowerment: Evolving Concepts and Alternative Measures,FISCAL STUDIES, Issue 4 2008Jameson Boex H11; H70; H72 Abstract Decentralisation reforms are among the most common and significant public sector reforms, particularly in developing and transitional countries around the world. Despite the importance of the topic to policy practitioners and academic researchers alike and the extensive empirical research on the topic, there is consensus in the literature that the measures of decentralisation that are currently used are unsatisfactory. In response, we propose an alternative measure of fiscal decentralisation based on the notion that decentralisation is more than simply the inverse of centralisation. Following Bahl (2005), we consider fiscal decentralisation as ,the empowerment of people by the [fiscal] empowerment of their local governments'. Accordingly, we develop a measure of fiscal empowerment that allows us to quantify fiscal decentralisation as the gain in empowerment due to devolution and we analyse the proposed measures of empowerment and decentralisation for a cross-section of developing, transitional and industrialised countries. [source] Triassic metasedimentary successions across the boundary between the southern Apennines and the Calabrian Arc (northern Calabria, Italy)GEOLOGICAL JOURNAL, Issue 2 2005A. Iannace Abstract The boundary area between the Apenninic fold-and-thrust belt and the crystalline Calabrian Arc, located around Sangineto in northern Calabria, has been investigated. New geological mapping in the Sant'Agata area has been performed on the Triassic successions traditionally attributed to the metasedimentary San Donato Unit. This, coupled with a reappraisal of the stratigraphy and tectonics of coeval successions present more to the south in the Cetraro Unit, results in a new reconstruction of the Triassic evolution of all the metasedimentary successions found in the region. Four informal stratigraphic units have been distinguished in the S. Agata area. The lowest one (Unit A) consists of well-bedded metalimestones and bioturbated marly limestones that correlate with Ladinian,Carnian carbonates in nearby areas. A second unit (Unit B), never recognized before, contains a complex alternation of dolomites, phyllites and some meta-arenites containing several beds of Cavernoso facies, attributed to the Carnian. They grade upward to platform and platform-margin dolomites of Norian,Rhaetian age (Unit C) that in turn are replaced upward and laterally by a fourth unit (Unit D) consisting of well-bedded, dark dolomites and metalimestones with marly interlayers locally found as resedimented large blocks in slope conglomerates. Unit D correlates with Rhaetian,Liassic beds in nearby areas. Several pieces of evidence of post-metamorphic contractional tectonics, with 140°N and 30°N trends, are found together with evidence of SW-directed extension. The siliciclastic Carnian beds of Unit B are correlated with the phyllites of Cetraro, formerly believed to be Middle Triassic; moreover, it is suggested that in the Cetraro area Unit C is almost totally replaced by Unit D. This demonstrates that the former distinction between the two tectonic units in the whole area has to be discarded. We have made a general palaeoenvironmental reconstruction which progresses laterally, during Ladinian,Carnian times, from (i) a coastal, mixed siliciclastic,carbonate,evaporitic area at Cetraro to (ii) a transitional carbonate shelf where siliciclastic input was only episodic, and finally to (iii) a bioconstructed margin which was later replaced by a steepened margin created by tectonic instability. Starting from the Norian, subsidence shifted toward the former coastal area where an intraplatform, restricted basin developed. The proposed stratigraphy corresponds closely to the Alpujarride units of the Betic Cordillera, Spain. Moreover, it is shown that strong affinities also exist, in terms of the structural framework, with the metamorphic units of Tuscany and Liguria. Copyright © 2005 John Wiley & Sons, Ltd. [source] The 1994 Sefidabeh earthquakes in eastern Iran: blind thrusting and bedding-plane slip on a growing anticline, and active tectonics of the Sistan suture zoneGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2000M. Berberian Summary In 1994 a sequence of five earthquakes with Mw 5.5,6.2 occurred in the Sistan belt of eastern Iran, all of them involving motion on blind thrusts with centroid depths of 5,10 km. Coseismic ruptures at the surface involved bedding-plane slip on a growing hanging-wall anticline displaying geomorphological evidence of uplift and lateral propagation. The 1994 earthquakes were associated with a NW-trending thrust system that splays off the northern termination of a major N,S right-lateral strike-slip fault. Elevation changes along the anticline ridge suggest that displacement on the underlying thrust dies out to the NW, away from its intersection with the strike-slip fault. This is a common fault configuration in eastern Iran and accommodates oblique NE,SW shortening across the N,S deforming zone, probably by anticlockwise rotations about a vertical axis. This style of fault kinematics may be transitional to a more evolved state that involves partitioning of the strike-slip and convergent motion onto separate subparallel faults. [source] Large eddy simulation of flow and scalar transport in a round jetHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 3 2004Hitoshi Suto Abstract Large eddy simulation (LES) was performed for a spatially developing round jet and its scalar transport at four steps of Reynolds number set between 1200 and 1,000,000. A simulated domain, which extends 30 times the nozzle diameter, includes initial, transitional, and established stage of jet. A modified version of convection outflow condition was proposed in order to diminish the effect of a downstream boundary. Tested were two kinds of subgrid scale (SOS) models: a Smagorinsky model (SM) and a dynamic Smagorinsky model (DSM). In the former model, parameters are kept at empirically deduced constants, while in the latter, they are calculated using different levels of space filtering. Data analysis based on the decay law of jet clearly presented the performance of SGS models. Simulated results by SM and DSM compared favorably with existing measurements of jet and its scalar transport. However, the quantitative accuracy of DSM was better than that of SM at a transitional stage of flow field. Computed parameters by DSM, coefficient for SGS stresses, CR and SGS eddy diffusivity ratio, ,SGS, were not far from empirical constants of SM. Optimization of the model coefficient was suggested in DSM so that coefficient CR was nearly equal in the established stage of jet but it was reduced in low turbulence close to the jet nozzle. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(3): 175,188, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20001 [source] Improvement of the basic correlating equations and transition criteria of natural convection heat transferHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 4 2001Shi-Ming Yang Abstract In this paper, improvements in the basic physical laws of natural convection heat transfer were implemented in two major respects by incorporating recent research findings in this field. A preferred transition criterion was adopted in this paper to correlate all of the experimental data. Since transition correlations are primarily flow stability problems, the Grashof number, instead of the Rayleigh number, was found to be the preferred criterion. Furthermore, in the case of natural convection heat transfer from a horizontal cylinder, a series of experimental data in the high-Rayleigh-number regions recently became available. These data made it possible to establish new reliable correlations and also to test the validity of previous correlations. It is concluded that the previous correlation for a horizontal cylinder in high-Rayleigh-number regions was based on unreliable experimental results. The transition correlation for a horizontal cylinder occurred at much higher values of Rayleigh number than the previous recommendation. In the case of natural convection heat transfer from a vertical plate, more accurate property values for air under pressurized conditions are now available. This made it possible to replot the reliable data of Saunders. From this result and the experimental result of Warner and Arpaci, a new set of basic correlations in natural convection heat transfer for laminar, transitional, and turbulent regimes are recommended. These recommendations reflect a better understanding of the basic physical laws in the field of heat convection. © 2001 Scripta Technica, Heat Trans Asian Res, 30(4): 293,300, 2001 [source] Defective Toll-like receptor 9-mediated cytokine production in B cells from Bruton's tyrosine kinase-deficient miceIMMUNOLOGY, Issue 2 2008Maroof Hasan Summary Bruton's tyrosine kinase (Btk), a member of the Tec family of tyrosine kinases, plays an important role in the differentiation and activation of B cells. Mutations affecting Btk cause immunodeficiency in both humans and mice. In this study we set out to investigate the potential role of Btk in Toll-like receptor 9 (TLR9) activation and the production of pro-inflammatory cytokines such as interleukin (IL)-6, tumour necrosis factor (TNF)-, and IL-12p40. Our data show that Btk-deficient B cells respond more efficiently to CpG-DNA stimulation, producing significantly higher levels of pro-inflammatory cytokines but lower levels of the inhibitory cytokine IL-10. The quantitative reverse transcription,polymerase chain reaction (RT-PCR) analysis presented in this work shows that mRNA production of one of the important new members of the IL-12 family, IL-27, was significantly increased in Btk-deficient B cells after CpG-DNA stimulation. In this study, we demonstrate significant differences in CpG responsiveness between transitional 1 (T1) and T2 B cells for survival and maturation. Furthermore, TLR9 expression, measured both as protein and as mRNA, was increased in Btk-defective cells, especially after TLR9 stimulation. Collectively, these data provide evidence in support of the theory that Btk regulates both TLR9 activation and expression in mouse splenic B cells. [source] Structure, function and evolution of the gas exchangers: comparative perspectivesJOURNAL OF ANATOMY, Issue 4 2002J. N. Maina Abstract Over the evolutionary continuum, animals have faced similar fundamental challenges of acquiring molecular oxygen for aerobic metabolism. Under limitations and constraints imposed by factors such as phylogeny, behaviour, body size and environment, they have responded differently in founding optimal respiratory structures. A quintessence of the aphorism that ,necessity is the mother of invention', gas exchangers have been inaugurated through stiff cost,benefit analyses that have evoked transaction of trade-offs and compromises. Cogent structural,functional correlations occur in constructions of gas exchangers: within and between taxa, morphological complexity and respiratory efficiency increase with metabolic capacities and oxygen needs. Highly active, small endotherms have relatively better-refined gas exchangers compared with large, inactive ectotherms. Respiratory structures have developed from the plain cell membrane of the primeval prokaryotic unicells to complex multifunctional ones of the modern Metazoa. Regarding the respiratory medium used to extract oxygen from, animal life has had only two choices , water or air , within the biological range of temperature and pressure the only naturally occurring respirable fluids. In rarer cases, certain animals have adapted to using both media. Gills (evaginated gas exchangers) are the primordial respiratory organs: they are the archetypal water breathing organs. Lungs (invaginated gas exchangers) are the model air breathing organs. Bimodal (transitional) breathers occupy the water,air interface. Presentation and exposure of external (water/air) and internal (haemolymph/blood) respiratory media, features determined by geometric arrangement of the conduits, are important features for gas exchange efficiency: counter-current, cross-current, uniform pool and infinite pool designs have variably developed. [source] One-Dimensional Rabbit Sinoatrial Node Models:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2003Benefits, Limitations Introduction: Cardiac multicellular modeling has traditionally focused on ventricular electromechanics. More recently, models of the atria have started to emerge, and there is much interest in addressing sinoatrial node structure and function. Methods and Results: We implemented a variety of one-dimensional sinoatrial models consisting of descriptions of central, transitional, and peripheral sinoatrial node cells, as well as rabbit or human atrial cells. These one-dimensional models were implemented using CMISS on an SGI® Origin® 2000 supercomputer. Intercellular coupling parameters recorded in experimental studies on sinoatrial node and atrial cell-pairs under-represent the electrotonic interactions that any cardiomyocyte would have in a multidimensional setting. Unsurprisingly, cell-to-cell coupling had to be scaled-up (by a factor of 5) in order to obtain a stable leading pacemaker site in the sinoatrial node center. Further critical parameters include the gradual increase in intercellular coupling from sinoatrial node center to periphery, and the presence of electrotonic interaction with atrial cells. Interestingly, the electrotonic effect of the atrium on sinoatrial node periphery is best described as opposing depolarization, rather than necessarily hyperpolarizing, as often assumed. Conclusion: Multicellular one-dimensional models of sinoatrial node and atrium can provide useful insight into the origin and spread of normal cardiac excitation. They require larger than "physiologic" intercellular conductivities in order to make up for a lack of "anatomical" spatial scaling. Multicellular models for more in-depth quantitative studies will require more realistic anatomico-physiologic properties. (J Cardiovasc Electrophysiol, Vol. 14, pp. S121-S132, October 2003, Suppl.) [source] Investigation of multiphase hydrogenation in a catalyst-trap microreactorJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 3 2009S. McGovern BACKGROUND: Multiphase hydrogenation plays a critical role in the pharmaceutical industry. A significant portion of the reaction steps in a typical fine chemical synthesis are catalytic hydrogenations, generally limited by resistances to mass and heat transport. To this end, the small-scale and large surface-to-volume ratios of microreactor technology would greatly benefit chemical processing in the pharmaceutical and other industries. A silicon microreactor has been developed to investigate mass transfer in a catalytic hydrogenation reaction. The reactor design is such that solid catalyst is suspended in the reaction channel by an arrangement of catalyst traps. The design supports the use of commercial catalyst and allows control of pressure drop across the bed by engineering the packing density. RESULTS: This paper discusses the design and operation of the reactor in the context of the liquid-phase hydrogenation of o-nitroanisole to o-anisidine. A two-phase ,flow map' is generated across a range of conditions depicting three flow regimes, termed gas-dominated, liquid-dominated, and transitional, all with distinctly different mass transfer behavior. Conversion is measured across the flow map and then reconciled against the mass transfer characteristics of the prevailing flow regime. The highest conversion is achieved in the transitional flow regime, where competition between phases induces the most favorable gas,liquid mass transfer. CONCLUSION: The results are used to associate a mass transfer coefficient with each flow regime to quantify differences in performance. This reactor architecture may be useful for catalyst evaluation through rapid screening, or in large numbers as an alternative to macro-scale production reactors. Copyright © 2008 Society of Chemical Industry [source] Nursing home care: whodunit?JOURNAL OF CLINICAL NURSING, Issue 11 2006Aggie TG Paulus PhD Aims and objectives., (1) To analyse and compare (changes and differences in) activity profiles of various types of nursing home care. (2) To assess the impact of integrated care on these activity profiles. Background., Because of an ongoing introduction of integrated nursing home care, caregivers increasingly have to co-ordinate their activities, engage into interprofessional relationships and take over each other's tasks. Consequently, activity profiles [i.e. combinations of (contributions to) care activities and the roles that perform them] are expected to change. Design/methods., At three measurement points in the period 1999,2003, caregivers (in 18 different roles) recorded and listed direct and indirect care activities. A total of 41 335 lists were analysed to derive activity profiles of traditional, transitional and integrated nursing home care in the Netherlands. Results., Traditional, transitional and integrated care shared some comparable activity profiles. Integrated care differed from the other types with respect to the contribution of the geriatric nurse, recreational activities supervisor, nutrition assistant, household assistant and nursing assistant to activities such as extra care, handling food and club activities. Contrary to the other roles, the licensed practical nurse contributed to (almost) all activities in all types of care. Conclusions., Nursing home care has several recurring activity profiles. These profiles are the same in all types of nursing home care. The introduction of integrated care implies that particular profiles have to be added to these profiles. As a generalist, the licensed practical nurse seems to play a key role in all activity profiles. Relevance to clinical practice., Because of demographic and financial pressures, integrated care for older people becomes increasingly important. By addressing the impact of integrated care on activity profiles, this paper provides information on how new types of care can be delivered in the most effective manner. [source] Agitation and mobilization of thixotropic liquidsAICHE JOURNAL, Issue 9 2010J. J. Derksen Abstract Direct numerical simulations of transitional and turbulent flows of purely viscous thixotropic liquids in stirred tanks have been performed. The simple thixotropy model used is based on the notion of a network in the liquid with an integrity that builds up with finite rate under quiescent conditions, and breaks down under liquid deformation. We solve a transport equation for the network integrity which is two-way coupled to the lattice-Boltzmann-based flow solver. The liquid's time scale characterized by the dimensionless Deborah number shows a profound impact on the level of mobilization and the flow patterns in the mixing tanks, especially if the time scale of the liquid is of the same order as the circulation time in the tank. It is also demonstrated to what extent increasing the impeller speed improves mobilization and mixing. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] Creating Mature Thinkers in Interior Design: Pathways of Intellectual DevelopmentJOURNAL OF INTERIOR DESIGN, Issue 3 2010Candy Carmel-Gilfilen M. Arch. Critical thinking skills are essential to meeting the economic, sustainable, and social challenges of the future. The purpose of this study was to explore critical thinking in interior design students using the W. G. Perry (1968) scheme, a model of epistemic cognitive development describing how thinking in college students progresses from black-and-white absolutes to a contextual understanding of knowledge. The authors present findings from a study involving 32 beginning and intermediate interior design students who were empirically assessed on global and design-specific thought development using the Measure of Intellectual Development (Widick & Knefelkamp, 1974) and the Measure of Designing (Portillo, 1987), respectively. The study objectives were to examine thought development in interior design students, investigate the relationship between global and design thinking, and explore relationships between thought development, student performance, and class standing. The results supported three levels of thought development: dualistic, transitional, and multiplistic with overall thinking appeared to be more advanced than thinking in design. The study also revealed both types of thinking significantly related to studio performance and class standing. The Perry model appears to have strong potential for understanding thought development in interior design students. [source] The effects of a transitional discharge model for psychiatric patientsJOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 1 2004W. REYNOLDS phd mphil rn This pilot randomized control trial was motivated by the discovery that many individuals with mental health problems are re-hospitalized within a year, with many being unable to fully adjust to community living. A solution was proposed in the form of an intervention called transitional discharge. The transitional discharge model included: (1) peer support, which is assistance from former patients who provide friendship, understanding and encouragement; and (2) overlap of inpatient and community staff in which the inpatient staff continue to work with the discharged patient until a working relationship is established with a community care provider. The overall aim of this study was to test the discharge model designed to assist patients discharged from acute admission wards to adjust to community living. This aim was tested through a number of related hypotheses, which suggest that, 5 months following discharge from an acute admission ward of a psychiatric hospital, individuals participating in a transitional discharge model: (1) report fewer symptoms; (2) report better levels of functioning; (3) have better quality of life; (4) are less likely to have been re-admitted to hospital. The study used a randomized experimental design with two conditions: experimental and usual treatment. In general, both the control and the experimental group demonstrated significant improvements in symptom severity and functional ability after 5 months. Usual treatment subjects in the control group were more than twice as likely to be re-admitted to hospital. This study needs to be replicated in Scotland with a larger sample and with a modified variation of the intervention called the Transitional Care Intervention. [source] Magnetic Resonance Imaging and Histological Classification of Intracranial Meningiomas in 112 DogsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 3 2008B.K. Sturges Background: Intracranial meningiomas are the most common primary brain tumors in dogs. Classification of meningiomas by tumor grade and subtype has not been reported, and the value of magnetic resonance imaging (MRI) characteristics for predicting tumor subtype and grade has not been investigated. Hypothesis: Canine intracranial meningiomas are a heterogenous group of tumors with differing histological subtypes and grades. Prediction of histopathological classification is possible based on MRI characteristics. Animals: One hundred and twelve dogs with a histological diagnosis of intracranial meningioma. Methods: Retrospective observational study. Results: Meningiomas were overrepresented in the Golden Retriever and Boxer breeds with no sex predilection. The incidence of specific tumor grades was 56% benign (Grade I), 43% atypical (Grade II), and 1% malignant (Grade III). Grade I histological subtypes included meningothelial (43%), transitional (40%), microcystic (8%), psammomatous (6%), and angiomatous (3%). No statistically significant (P < .05) associations were found among tumor subtype or grade and any of the MRI features studied. Conclusions and Clinical Importance: Meningiomas in dogs differ from their counterparts in humans mainly in their higher incidence of atypical (Grade II) tumors observed. MRI characteristics do not allow for prediction of meningioma subtype or grade, emphasizing the necessity of histopathology for antemortem diagnosis. The higher incidence of atypical tumors in dogs may contribute to the poorer therapeutic response in dogs with meningiomas as compared with the response in humans with meningiomas. [source] Post-Apartheid Disgrace: Guilty Masculinities in White South African WritingLITERATURE COMPASS (ELECTRONIC), Issue 1 2005Georgie Horrell In the aftermath of the Truth and Reconciliation Commission in South Africa J. M. Coetzee writes of the ,system' of guilt and shame, debt and retribution which operates throughout society. He and writers like André Brink, Michiel Heyns and Troy Blacklaws tell stories which traverse and explore the paths tracked by society's quest for healing and restitution. This article considers a selection of transitional, contemporary white novels in South Africa in order to gesture towards discourses of both particular and global postcolonial significance, referring particularly to gender and representations of white masculinity in the post-apartheid era. [source] Forming supermassive black holes by accreting dark and baryon matterMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2006Jian Hu ABSTRACT Given a large-scale mixture of self-interacting dark matter (SIDM) particles and baryon matter distributed in the early Universe, we advance here a two-phase accretion scenario for forming supermassive black holes (SMBHs) with masses around ,109 M, at high redshifts z(,6). The first phase is conceived to involve a rapid quasi-spherical and quasi-steady Bondi accretion of mainly SIDM particles embedded with baryon matter on to seed black holes (BHs) created at redshifts z, 30 by the first generation of massive Population III stars; this earlier phase rapidly gives birth to significantly enlarged seed BH masses of during z, 20,15, where ,0 is the cross-section per unit mass of SIDM particles and Cs is the velocity dispersion in the SIDM halo referred to as an effective ,sound speed'. The second phase of BH mass growth is envisaged to proceed primarily via baryon accretion, eventually leading to SMBH masses of MBH, 109 M,; such SMBHs may form either by z, 6 for a sustained accretion at the Eddington limit or later at lower z for sub-Eddington mean accretion rates. In between these two phases, there is a transitional yet sustained diffusively limited accretion of SIDM particles which in an eventual steady state would be much lower than the accretion rates of the two main phases. We intend to account for the reported detections of a few SMBHs at early epochs, e.g. Sloan Digital Sky Survey (SDSS) 1148+5251 and so forth, without necessarily resorting to either super-Eddington baryon accretion or very frequent BH merging processes. Only extremely massive dark SIDM haloes associated with rare peaks of density fluctuations in the early Universe may harbour such early SMBHs or quasars. Observational consequences are discussed. During the final stage of accumulating a SMBH mass, violent feedback in circumnuclear environs of a galactic nucleus leads to the central bulge formation and gives rise to the familiar empirical MBH,,b correlation inferred for nearby normal galaxies with ,b being the stellar velocity dispersion in the galactic bulge; in our scenario, the central SMBH formation precedes that of the galactic bulge. [source] Blood pressure, seasonal body fat, heart rate, and ecological differences in Caboclo populations of the Brazilian AmazonAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2006H.P. Silva This study compares blood pressure (BP) and related cardiovascular risk factors among three Caboclo communities from the Brazilian Amazon. Its purpose is to investigate possible risk differentials related to variable ecological settings and Western influences. Caxiuanã is characterized as a more "traditional" group, while Aracampina and Santana are viewed as more "transitional" in lifestyle. A total of 348 subjects from the three communities were evaluated in the wet or the dry season or in both. Measurements across the communities were compared by season and sex. Results suggest little seasonal variation in average BP, BP change, body fat, or body fat change among men. Conversely, there is substantial seasonal and intercommunity variation among women. Additional analyses reveal (1) an inconsistent association between age and BP across the communities; (2) that BMI is not associated with BP transitional communities in either season but is associated with both systolic and diastolic pressure in the most traditional community; and (3) little to no sex effect on BP. These results suggest increased Western influence affects body composition particularly of women. However, increased BMI and fat among transitional Caboclo women does not directly translate into higher BP; rather, their BP appears to be more affected by seasonal stresses. Finally, conditions during the wet season diminish age-related variation in BP, suggesting that during the wet season these Caboclo may be less active. Am. J. Hum. Biol. 18:10,22, 2006. © 2005 Wiley-Liss, Inc. [source] Innovative Ways to Address the Mental Health and Medical Needs of Marginalized Patients: Collaborations Between Family Physicians, Family Therapists, and Family PsychologistsAMERICAN JOURNAL OF ORTHOPSYCHIATRY, Issue 3 2004Warren L. Holleman PhD This article describes an innovative program to meet the needs of homeless women, children, and families residing at a transitional living center in an urban setting. The program involves collaboration between medical and mental health professionals to address the multiple problems and unmet needs of this population. Recommendations for future work in expanding collaborative practice are discussed. [source] Rethinking local political leadershipPUBLIC ADMINISTRATION, Issue 4 2002Steve Leach The changing nature of local political leadership in Britain over the past 25 years has received scant attention from political scientists. This article argues that changes in the roles and functions of local authorities have had a marked impact on the nature of local political leadership. Three phases (operational, transitional and collaborative) are identified and leadership roles are related to changes in the political context of local government. The fundamental tasks of leadership have not changed but what has changed is the balance or relative emphasis between them and the way they have been interpreted. While elected local authorities cannot ignore the implications of the changed external agenda , notably the advent of new forms of executive leadership , the way they respond still bears the mark of the local political culture. [source] Mineralogy, Lithogeochemistry and Elemental Mass Balance of the Hydrothermal Alteration Associated with the Gold-rich Batu Hijau Porphyry Copper Deposit, Sumbawa Island, IndonesiaRESOURCE GEOLOGY, Issue 3 2009Arifudin Idrus Abstract This paper discusses the mineralogy, whole-rock geochemistry and elemental mass balance of the hydrothermal alteration zones within the Batu Hijau porphyry copper-gold deposit, Sumbawa Island, Indonesia. The hydrothermal alteration and mineralisation developed in four stages, namely (i) the early stage consisting of a central copper-gold-bearing biotite (potassic), proximal actinolite (inner propylitic) and the distal chlorite-epidote (outer propylitic) zones; (ii) the transitional stage represented by the chlorite-sericite (intermediate argillic) zone; (iii) the late stages distinguished into the sericite-paragonite (argillic) and pyrophyllite-andalusite (advanced argillic) zones; and (iv) the very late stage typified by the illite-sericite zone. In general, major elements (particularly Ca, Mg, Na and K) and some minor and rare earth elements decrease from the least altered rocks towards the late alteration zones as a consequence of the breakdown of Ca-bearing hornblende, biotite and plagioclase. Chemical discrimination by means of millicationic R1 -R2 diagram indicates that R1 [4Si , 11(Na + K) , 2(Fe + Ti)] increases while R2[6Ca + 2Mg + Al] decreases with increasing alteration intensity, from least-altered, through early, transitional, to late alteration zones. Rare earth elements-chondrite (C1) normalised patterns also exhibit the depletion of the elements through the subsequent alteration zones. These results are consistent with the elemental mass balance calculation using the isocon method which shows that the degree of mass and volume depletion systematically increases during alteration. A decrease of the elements as well as mass and volume from early, through transitional to late alteration stages may imply a general decrease of the element activities in hydrothermal fluids during the formation of the alteration zones. [source] Power draw of a high-Shear homogenizerTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2001Kevin J. Myers Abstract The power draw of a high-shear rotor-stator homogenizer has been characterized in laminar, transitional, and turbulent operation. The power draw is comprised of two components , that associated with mixing and that associated with a bushing and bearings in the device. In turbulent operation, the mixing power draw is influenced primarily by pumping mode (up- or down-pumping), and to a lesser extent, by vessel baffling and other geometric parameters. Mixing power draw can be characterized in terms of power number across the Reynolds number spectrum if an empirical Froude number correction is applied. La consommation de puissance d'un homogénéiseur à rotor-stator à fort cisaillement a été caractérisée pour un fonctionnement laminaire, de transition et turbulent. La consommation de puissance comporte deux composantes: celle associée au mélange et celle associée aux garnitures dans l'appareil. En mode turbulent, la puissance de mélange est principalement influencée par le mode de pompage (pompage vers le haut ou vers le bas), et dans une moindre mesure, par le système de chicanes du réservoir et autres paramètres géométriques. La puissance peut ,tre caractérisée en termes de nombre de puissance dans la gamme de nombres de Reynolds considérée si on utilise une correction du nombre de Froude empirique. [source] The Role of Individual Characteristics in Predicting the Stability of Party Identification: A Cross-Cultural StudyAPPLIED PSYCHOLOGY, Issue 3 2008Maria-Magdalena Farc The present study examined political partisanship stability in the context of transitional and consolidated democracies. We hypothesised that (a) in both democratic systems, personality differences as well as socialisation patterns and socioeconomic factors would be related to the stability of party identification directly, and that (b) the relationship between individual factors and party identification patterns would be moderated by democracy type and by socialisation strength. A total of 521 participants (293 American, 228 Romanian) completed surveys assessing partisanship stability, individual dispositions, socialisation strength, and socioeconomic status. In support of hypothesis (a), the stability of party identification was significantly predicted by socialisation, desire for control, and positive economic perceptions. In support of hypothesis (b), type of democracy moderated the relationship between economic perceptions and partisanship stability, and parental socialisation moderated the relationship between desire for control/self-consciousness and the stability of party identification. La présente étude examine la stabilité de la préférence politique dans un contexte de démocraties en transition ou consolidées. Nous faisons l'hypothèse que (a) dans les deux systèmes démocratiques, les différences de personnalité, comme les modèles de socialisation et les facteurs économiques sont directement liés à la stabilité d'identification à un parti et que (b) la relation entre les facteurs individuels et les modèles d'identification à un parti est affaibli par le type de démocratie et la force de la socialisation. Un total de 521 participants (293 Américains et 228 Roumains) ont répondu à une enquête évaluant la stabilité de la préférence, les dispositions individuelles, la force de la socialisation et le statut socio-économique. En accord avec l'hypothèse (a), la stabilité d'identification à un parti est significativement prédictible par la socialisation, le désir de contrôle et la perception positive de l'économie. En accord avec l'hypothèse (b), d'une part, le type de démocratie affaiblit la relation entre les perceptions de l'économie et la stabilité de la préférence, d'autre part, la socialisation parentale affaiblit le lien entre le contrôle/la conscience de soi et la stabilité de l'identification à un parti. [source] | ||||||||||||||||||||||||||||||||||||||||