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Uniform
Kinds of Uniform Terms modified by Uniform Selected AbstractsUniform hazard versus uniform risk bases for performance-based earthquake engineering of light-frame wood constructionEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 11 2010Yue Li Abstract This paper investigates the implications of designing for uniform hazard versus uniform risk for light-frame wood residential construction subjected to earthquakes in the United States. Using simple structural models of one-story residences with typical lateral force-resisting systems (shear walls) found in buildings in western, eastern and central regions of the United States as illustrations, the seismic demands are determined using nonlinear dynamic time-history analyses, whereas the collapse capacities are determined using incremental dynamic analyses. The probabilities of collapse, conditioned on the occurrence of the maximum considered earthquakes and design earthquakes stipulated in ASCE Standard 7-05, and the collapse margins of these typical residential structures are compared for typical construction practices in different regions in the United States. The calculated collapse inter-story drifts are compared with the limits stipulated in FEMA 356/ASCE Standard 41-06 and observed in the recent experimental testing. The results of this study provide insights into residential building risk assessment and the relation between building seismic performance implied by the current earthquake-resistant design and construction practices and performance levels in performance-based engineering of light-frame wood construction being considered by the SEI/ASCE committee on reliability-based design of wood structures. Further code developments are necessary to achieve the goal of uniform risk in earthquake-resistant residential construction. Copyright © 2010 John Wiley & Sons, Ltd. [source] A Post-Modification Strategy for the Synthesis of Uniform, Hydrophilic/Hydrophobic Patterned ,-Hydroxy Acid OligomersEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 31 2009Nadja Franz Abstract Hydrophilic/hydrophobic patterning is a well-established design strategy to guide secondary structure formation of both natural as well as non-natural oligomers and polymers. This contribution explores the feasibility of a new approach for the synthesis of uniform, sequence-defined, hydrophilic/hydrophobic patterned oligo(,-hydroxy acid)s. The proposed strategy is based on post-modification of a reactive oligoester scaffold composed of an alternating sequence of hydrophobic [(2S)-2-hydroxy-4-methylpentanoic acid] and masked hydrophilic [(2S)-2-hydroxypent-4-enoic acid] ,-hydroxy acids. The use of (2S)-2-hydroxypent-4-enoic acid instead of a complex side-chain-protected hydrophilic building block obviates the need for additional protective group chemistry during chain extension. In a subsequent post-modification step, the allyl side chains can be quantitatively modified via free-radical addition of different ,-functional thiols to afford hydrophilic/hydrophobic patterned oligoesters. The proposed synthetic strategy provides an interesting alternative to rapidly generate libraries of foldamers with identical chain length and monomer sequence but different side-chain functionalities.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Preparation of Uniform, Water-Soluble, and Multifunctional Nanocomposites with Tunable SizesADVANCED FUNCTIONAL MATERIALS, Issue 5 2010Dechao Niu Abstract Novel, thiol-functionalized, and superparamagnetic, silica composite nanospheres (SH-SSCNs) with diameters smaller than 100,nm are successfully fabricated through the self-assembly of Fe3O4 nanoparticles and polystyrene100 - block -poly(acrylic acid)16 and a subsequent sol-gel process. The size and magnetic properties of the SH-SSCNs can be easily tuned by simply varying the initial concentrations of the magnetite nanoparticles in the oil phase. By incorporating fluorescent dye molecules into the silica network, the composite nanospheres can be further fluorescent-functionalized. The toxicity of the SH-SSCNs is evaluated by choosing three typical cell lines (HUVEC, RAW264.7, and A549) as model cells, and no toxic effects are observed. It is also demonstrated that SH-SSCNs can be used as a new class of magnetic resonance imaging (MRI) probes, having a remarkably high spin,spin (T2) relaxivity (r2*,=,176.1,mM,1 S,1). The combination of the sub-100-nm particle size, monodispersity in aqueous solution, superparamagnetism, and fluorescent properties of the SH-SSCNs, as well as the non-cytotoxicity in vitro, provides a novel and potential candidate for an earlier MRI diagnostic method of cancer. [source] Spies in Uniform: British Military and Naval Intelligence on the Eve of the First World War By Matthew S. SeligmannHISTORY, Issue 304 2006JEREMY BLACK No abstract is available for this article. [source] Comments on ,Electric-Field-Assisted Growth of Highly Uniform and Oriented Gold Nanotriangles on Conducting Glass Substrates'ADVANCED MATERIALS, Issue 13 2009Peng Diao AFM artifacts: Recent results by Sajanlal and Pradeep on the electric-field-assisted growth of highly uniform and oriented gold nanotriangles appear to provide a simple route to the size-, shape-, and orientation-controlled synthesis of nano structures. In our view, however, the triangle patterns observed in the AFM images are not real surface features but artifacts produced by a broken or contaminated AFM tip. [source] Reply to "Comments on Electric-Field-Assisted Growth of Highly Uniform and Oriented Gold Nanotriangles on Conducting Glass Substrates"ADVANCED MATERIALS, Issue 13 2009Panikkanvalappil R. Sajanlal [source] Growth and Optical Properties of Highly Uniform and Periodic InGaN Nanostructures,ADVANCED MATERIALS, Issue 13 2007P. Chen InGaN nanodot arrays with improved optical properties, attributed to the strong localization of photogenerated carriers in the size-homogeneous nanodots, grown by nanoscale selective area epitaxy (NSAE) on electron-beam lithographically patterned templates are presented. The figure shows an array of 60,nm diameter cone-shaped InGaN nanodots with 200,nm spacing, and a single nanodot (inset). [source] Low-Temperature Synthesis of Star-Shaped PbS Nanocrystals in Aqueous Solutions of Mixed Cationic/Anionic Surfactants,ADVANCED MATERIALS, Issue 3 2006N. Zhao Uniform, well-defined star-shaped PbS nanocrystals with tunable sizes (40,100,nm, see Figure), as well as octahedral PbS nanocrystals, have been readily synthesized in aqueous solutions containing a mixture of the surfactants cetyltrimethylammonium bromide/ sodium dodecyl sulfate (CTAB/SDS) at low temperature (80,°C). The size of the PbS nanostars can be accurately controlled by adjusting the reaction time. This result may open new avenues for the green chemical synthesis of shape-controlled semiconductor nanocrystals. [source] Synthesis of Mesoporous Organosilicate Films in Supercritical Carbon Dioxide,ADVANCED MATERIALS, Issue 2 2006A. Pai Uniform, well-ordered, mesoporous organosilicate films (see Figure) have been synthesized by efficient direct and post-synthesis functionalization methods in supercritical carbon dioxide and characterized using spectroscopic, microscopy, and diffraction techniques. These materials have numerous potential applications, including in sensors, low- k dielectrics, separations, and catalysis. [source] The Combination of Colloid-Controlled Heterogeneous Nucleation and Polymer-Controlled Crystallization: Facile Synthesis of Separated, Uniform High-Aspect-Ratio Single-Crystalline BaCrO4 NanofibersADVANCED MATERIALS, Issue 2 2003S.-H. Yu Uniform, separated BaCrO4 single-crystalline nanofibers with high aspect ratio (>,5000, see Figure) can be fabricated at room temperature in aqueous solution using a double hydrophilic block copolymer as structure-directing agent and introducing colloidal nucleation agents. Such fibers represent a model case for advanced polymer fillers and the exploration of quasi-1D nanostructures with interesting electrical, optical, or catalytic properties. [source] A Customizable Instrument for Measuring the Mechanical Properties of Thin Biomedical MembranesMACROMOLECULAR MATERIALS & ENGINEERING, Issue 10 2005Gracián Triviño Abstract Summary: A customized instrument has been developed as part of multidisciplinary research work relating to the development of a biodegradable vascular scaffold. This instrument aims to measure the mechanical properties of elastic and viscoelastic thin membranes with tissue engineering applications. Uniform and omni-directional pressure is applied on the whole membrane which is uniformly clamped and submerged into a liquid medium. The mechanical testing described in this study is focused on the stress-strain curves of polycaprolactone (PCL) films after different treatments. The influence of Dulbecco's modified Eagle's culture medium, L929 fibroblast culture, NaOH treatment and film thickness on the mechanical properties of PCL films was evaluated after different times. These studies show that the PCL degradation process is influenced by immersion in the culture medium, inducing an increment in the slope of the pressure-dilation curve which is indicative of an increase in the polymer stiffness. On the other hand, long NaOH treatments make PCL films have more flexible behavior. A computerized version of the instrument: (1) Electrical compressor; (2) Filter; (3) Voltage-pressure converter; (5) Pressure sensor; (6) Differential pressure sensor; (7,8) Main and auxiliary pipettes; (9) Printed circuit board; (10) Personal computer. [source] A Novel, Facile Method for the Preparation of Uniform, Reactive Maleic Anhydride/Vinyl Acetate Copolymer Micro- and NanospheresMACROMOLECULAR RAPID COMMUNICATIONS, Issue 17 2004Chang-Min Xing Abstract Summary: A novel, stabilizer-free dispersion polymerization with alkyl esters as reaction media gives uniform alternating microspheres of maleic anhydride (MAn)/vinyl acetate (VAc) copolymer. The diameter of the copolymer microspheres could be precisely controlled from 80 to 750 nm by changing the monomer concentration or feed ratio. Moreover, this new type of copolymer microspheres with reactive anhydride groups on the surface has good solubility in common nontoxic solvents such as water and ethanol. SEM image of the powder surface of copolymer microspheres formed at [MAn],=,[VAc],=,1.5 M. [source] Nash bargaining over allocations in inventory pooling contractsNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 6 2008Eran Hanany Abstract When facing uncertain demand, several firms may consider pooling their inventories leading to the emergence of two key contractual issues. How much should each produce or purchase for inventory purposes? How should inventory be allocated when shortages occur to some of the firms? Previously, if the allocations issue was considered, it was undertaken through evaluation of the consequences of an arbitrary priority scheme. We consider both these issues within a Nash bargaining solution (NBS) cooperative framework. The firms may not be risk neutral, hence a nontransferable utility bargaining game is defined. Thus the physical pooling mechanism itself must benefit the firms, even without any monetary transfers. The firms may be asymmetric in the sense of having different unit production costs and unit revenues. Our assumption with respect to shortage allocation is that a firm not suffering from a shortfall, will not be affected by any of the other firms' shortages. For two risk neutral firms, the NBS is shown to award priority on all inventory produced to the firm with higher ratio of unit revenue to unit production cost. Nevertheless, the arrangement is also beneficial for the other firm contributing to the total production. We provide examples of Uniform and Bernoulli demand distributions, for which the problem can be solved analytically. For firms with constant absolute risk aversion, the agreement may not award priority to any firm. Analytically solvable examples allow additional insights, e.g. that higher risk aversion can, for some problem parameters, cause an increase in the sum of quantities produced, which is not the case in a single newsvendor setting. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 [source] Closed-form minimax time-delay filters for underdamped systemsOPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 3 2007Tarunraj Singh Abstract This paper derives closed-form solutions for the parameters of a time-delay filter designed to be robust to uncertainties in frequencies to be cancelled. It is shown that the slope of the magnitude plot of the two time-delay filter is zero at the nominal frequency indicating that it is a local maximum. This information is used for deriving the solution of the parameters of the time-delay filter in closed form. Three time-delay filters are also designed which force a zero of the filter to be located at the nominal frequency of the system. Uniform and non-uniform distributions of the penalty over the uncertain regions are permitted in this formulation. The applicability of the proposed technique for the control of multi-mode systems is also illustrated. Copyright © 2006 John Wiley & Sons, Ltd. [source] Detection of royal jelly adulteration using carbon and nitrogen stable isotope ratio analysisRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 2 2006A. Stocker Stable isotope ratios (13C/12C and 15N/14N) were measured in royal jelly (RJ) samples by isotope ratio mass spectrometry (IRMS) to evaluate authenticity and adulteration. Carbon and nitrogen isotope contents (given as delta values relative to a standard, ,13C, ,15N) of RJ samples from various European origins and samples from commercial sources were analyzed. Uniform ,13C values from ,26.7 to ,24.9, were observed for authentic RJ from European origins. Values of ,15N ranged from ,1.1 to 5.8, depending on the plant sources of nectars and pollen. High ,13C values of several commercial RJ samples from ,20.8 to ,13.3, indicated adulteration with high fructose corn syrup (HFCS) as a sugar source. Use of biotechnologically produced yeast powder as protein source for the adulterated samples was assumed as ,15N values were lower, as described for C4 or CAM plant sources. RJ samples from authentic and from adulterated production were distinguished. The rapid and reliable method is suitable for urgent actual requirements in food monitoring. Copyright © 2005 John Wiley & Sons, Ltd. [source] Understanding the properties of aerobic sludge granules as hydrogelsBIOTECHNOLOGY & BIOENGINEERING, Issue 5 2009Thomas Seviour Abstract Aerobic sludge granules are larger, denser microbial aggregates than activated sludge flocs with a smoother and more regular surface, which facilitates greater wastewater treatment intensity. Factors important in their growth are still poorly understood, which is an impediment to the construction and operation of full-scale aerobic sludge granule processes. Data in this article obtained with granules treating an abattoir wastewater provide evidence that aerobic sludge granules are hydrogels. The results also demonstrate a method for characterizing macromolecular associations. The rheological profile of these granules was found to be analogous with that of typical polymer gels. Water uptake or swelling reflects an equilibrium between granule elastic modulus and osmotic pressure, whereby uptake is increased by reducing solute concentration or the elastic modulus. A weakening of the extracellular polymeric substance (EPS) matrix as demonstrated with mechanical spectroscopy was induced by several environmental factors including temperature, pH and ionic strength. Uniform and elastic deformation was observed at low strain. Enzymatic degradation studies indicate that proteins and ,-polysaccharides were the major granule structural materials. The aerobic sludge granules in the current study were therefore protein,polysaccharide composite physical hydrogels. While aerobic sludge granules treating an abattoir wastewater are used as a case study, many of the fundamental principles detailed here are relevant to other granulation processes. The paradigm established in this study can potentially be applied to better understand the formation of aerobic sludge granules and thus overcome a hurdle in the acceptance of aerobic sludge granulation as an alternative to more traditional wastewater treatment processes. Biotechnol. Bioeng. 2009;102: 1483,1493. © 2008 Wiley Periodicals, Inc. [source] Request for existing experimental datasets on color differencesCOLOR RESEARCH & APPLICATION, Issue 2 2007Manuel Melgosa Abstract The Technical Committee 1-55 of the International Commission on Illumination on "Uniform color space for industrial color difference evaluation" is requesting the submission of datasets for use in developing a new approximately uniform color space for industrial use. The data should be submitted to the TC Chair, Dr. Manuel Melgosa at the University of Granada. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 159, 2007 [source] Texas Trooper Uniforms: Assessment of Fabrics, Comfort, and WearFAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 3 2002Patricia E. Horridge Using the physical dimension triad of Branson and Sweeney's Model for Clothing Comfort as a conceptual framework, the purpose of the study was to examine the effects of cotton/wool fabrics on comfort and wear of trooper uniforms. Participants were 10 troopers recruited for wear- testing uniforms developed in accordance to Texas Department of Public Safety specifications. Trooper shirt and pants fabrics were developed in two fiber contents (80/20 and 70/30 cotton/wool) and tested before and after dry-cleaning. Twenty constructed uniforms and 10 issued uniforms were worn through four wear-refurbishing-dry-cleaning cycles. Surveys and scales were used to gather data during and after wear testing; data were analyzed by t-test and ANOVAs. Branson and Sweeney's comfort model was supported, in part, with person attributes (body weight, hours uniform worn) affecting uniform comfort. Implications are given for fabric producers and garment manufacturers. [source] A Retrograde Step: The Potential Impact of High Visibility Uniforms Within Youth Justice ReparationTHE HOWARD JOURNAL OF CRIMINAL JUSTICE, Issue 1 2010NICHOLAS PAMMENT Abstract: The Labour government has recently introduced uniforms for adult offenders undertaking community service as part of their community orders. There have also been calls within the youth justice arena to introduce uniforms to young offenders undertaking reparation. Through observations, interviews and questionnaires with young offenders and their supervising staff, we argue that the introduction of uniforms will be counterproductive on a number of levels. In short, it would be a retrograde step. We conclude with a suggestion on how to increase the visibility of unpaid work by offenders within the community, without the negative impact of uniforms. [source] Manifold Homotopy via the Flow ComplexCOMPUTER GRAPHICS FORUM, Issue 5 2009Bardia Sadri Abstract It is known that the critical points of the distance function induced by a dense sample P of a submanifold , of ,n are distributed into two groups, one lying close to , itself, called the shallow, and the other close to medial axis of ,, called deep critical points. We prove that under (uniform) sampling assumption, the union of stable manifolds of the shallow critical points have the same homotopy type as , itself and the union of the stable manifolds of the deep critical points have the homotopy type of the complement of ,. The separation of critical points under uniform sampling entails a separation in terms of distance of critical points to the sample. This means that if a given sample is dense enough with respect to two or more submanifolds of ,n, the homotopy types of all such submanifolds together with those of their complements are captured as unions of stable manifolds of shallow versus those of deep critical points, in a filtration of the flow complex based on the distance of critical points to the sample. This results in an algorithm for homotopic manifold reconstruction when the target dimension is unknown. [source] Characterization of reactive DC magnetron sputtered TiAlN thin filmsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2008B. Subramanian Abstract Thin films of about 1,m Titanium Aluminum Nitride (TiAlN) were deposited onto mild steel substrates by reactive direct current (DC) magnetron sputtering using a target consisting of equal segments of titanium and aluminum. X-ray diffraction (XRD) analysis showed that the TiAlN phase had preferred orientations along 111 and 200 with the face-centered cubic structure. Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) analyses indicated that the films were uniform and compact. Photoluminescence (PL) spectra reveal that TiAlN thin films are of good optical quality. Laser Raman studies revealed the presence of characteristic peaks of TiAlN at 312.5, 675, and 1187.5 cm,1. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Crystal growth, optical and luminescence properties of (Ce,Sr)-doped PrAlO3 single crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2007A. Novoselov Abstract Using the micro-pulling-down method, (Ce,Sr)-doped PrAlO3 square-shaped single crystals (4×4×12 mm) were grown. Structural parameters studied by X-ray powder diffraction were consistent with R3m space group. Compositional homogeneity was checked with electron probe micro-analysis and found quite uniform. Absorption spectra and luminescence characteristics under UV and X-ray excitations were measured at room temperature with no Ce-related emission appeared. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Rearrangement of microtubule polarity orientation during conversion of dendrites to axons in cultured pyramidal neuronsCYTOSKELETON, Issue 5 2007Daisuke Takahashi Abstract Axons and dendrites of neurons differ in the polarity orientation of their microtubules. Whereas the polarity orientation of microtubules in axons is uniform, with all plus ends distal, that in dendrites is nonuniform. The mechanisms responsible for establishment and maintenance of microtubule polarity orientation in neuronal processes remain unclear, however. We previously described a culture system in which dendrites of rat cortical neurons convert to axons. In the present study, we examined changes in microtubule polarity orientation in such dendrites. With the use of the hooking procedure and electron microscopy, we found that microtubule polarity orientation changed from nonuniform to uniform, with a plus end-distal arrangement, in dendrites that gave rise to axons during culture of neurons for 24 h. Microtubule polarity orientation remained nonuniform in dendrites that did not elongate. Axon regeneration at the dendritic tip thus triggered the disappearance of minus end-distal microtubules from dendrites. These minus end-distal microtubules also disappeared from dendrites during axon regeneration in the presence of inhibitors of actin polymerization, suggesting that actin-dependent transport of microtubules is not required for this process and implicating a previously unidentified mechanism in the establishment and maintenance of microtubule polarity orientation in neuronal processes. Cell Motil. Cytoskeleton 2007. © 2007 Wiley-Liss, Inc. [source] Does Imiquimod Histologically Rejuvenate Ultraviolet Radiation,Damaged Skin?DERMATOLOGIC SURGERY, Issue 12 2007KATHLEEN SMITH MD BACKGROUND Imiquimod (IMI) 5% is believed by some to result in an improved cosmetic appearance of chronically ultraviolet radiation (UV)-damaged skin. OBJECTIVE The objective was to determine what histologic and immunohistologic changes were present in actinically damaged skin after treatment with IMI. METHODS AND MATERIALS Pre- and posttherapy biopsies of 12 patients with histories of actinic keratoses were evaluated with routine histology and immunohistochemical stains including p53, p63, proliferating cell nuclear antigen (PCNA), c-kit, and Factor XIIIa. RESULTS After IMI therapy there was less compact hyperkeratosis, a more uniform rete ridge pattern with a more ordered proliferation of the epidermis, and a decrease in sun-damaged melanocytes. The papillary dermis showed a more uniform cellularity, and there was increased cellularity within the area of solar elastosis. After therapy, staining for p53, p63, and PCNA was decreased within the epidermis; staining for c-kit was decreased but more uniform in the basal cell; and Factor XIIIa expression was increased within the papillary dermis with a more ordered pattern of staining. CONCLUSION These morphologic and immunohistochemical patterns may explain some of the improvement in overall skin appearance after IMI therapy and may be related to the spectrum of signaling pathways induced by the imidazoquinolines. [source] Rapid Development of Keratoacanthomas After a Body PeelDERMATOLOGIC SURGERY, Issue 2 2003SueEllen Cox MD Resurfacing techniques have been traditionally limited to the face because of a lack of predictability and standardization for peeling nonfacial skin. There is a need for medical and surgical intervention for treating nonfacial skin that is actinically damaged. Medium-depth chemical peels (Jessner +35% trichloroacetic acid) remove the photodamaged epidermis to stimulate the production of new collagen in the dermis and remove lesions associated with facial actinic damage, including lentigines and actinic keratoses. Widespread actinic damage is common on the arms and chest. A 70% glycolic acid gel plus 40% trichloroacetic acid peel (Cook Body Peel) is a controlled peel that predictably enables peeling of nonfacial skin in a uniform and safe fashion with specific clinical endpoints. An unusual complication of this body peel is reported. [source] Neurodevelopmental outcomes of children with low-grade gliomasDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2008M. Douglas Ris Abstract As a group, children with low-grade gliomas (LGGs) enjoy a high rate of long-term survival and do not require the intensity of neurotoxic treatments used with higher risk pediatric brain tumors. Because they are generally considered to have favorable neurobehavioral outcomes, they have not been studied as thoroughly as higher-grade brain tumors by late-effects researchers. In this article, we review the literature on the neurobehavioral effects associated with low-grade gliomas and conclude that, (1) this is a large, understudied group of survivors of pediatric brain tumors; (2) recent small- and large-scale studies document increased risk in multiple cognitive-behavioral domains after treatment for LGGs compared with healthy peers; (3) such risk is not uniform but varies with tumor location and treatments; and (4) a life span development perspective is essential to a complete understanding of the risks faced by these children. More research on the most efficacious biopsychosocial treatment models for improving the outcomes of survivors of low-grade glioma is recommended, informed by a better understanding of theireducational needs. Investigations of genetic influences on outcome as well as prospective studies of these patients as they age are also recommended. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:196,202. [source] Estimating the spatiotemporal pattern of volumetric growth rate from fate maps in chick limb developmentDEVELOPMENTAL DYNAMICS, Issue 2 2009Yoshihiro Morishita Abstract Morphogenesis is achieved through volumetric growth of tissue at a rate varying over space and time. The volumetric growth rate of each piece of tissue reflects the behaviors of constituent cells such as cell proliferation and death. Hence, clarifying its spatiotemporal pattern accurately is a key to bridge between cell behaviors and organ morphogenesis. We here propose a new method to estimate the spatiotemporal pattern of volumetric growth rate from fate map data with limited resolution on space and time by using a mathematical model. We apply the method to chick wing data along the proximodistal axis, and find that the volumetric growth pattern is biphasic: it is spatially uniform in earlier stages (until stage 23), but in later stages the volumetric growth occurs approximately 4.5 times as fast as in the distal region (within approximately 100 ,m from the limb tip) than in the proximal region. Developmental Dynamics 238:415,422, 2009. © 2009 Wiley-Liss, Inc. [source] Development of the corneal stroma, and the collagen,proteoglycan associations that help define its structure and functionDEVELOPMENTAL DYNAMICS, Issue 10 2008Andrew J. Quantock Abstract The cornea of the eye is a unique, transparent connective tissue. It is comprised predominantly of collagen fibrils, remarkably uniform in diameter and regularly spaced, organized into an intricate lamellar array. Its establishment involves a precisely controlled sequence of developmental events in which the embryonic cornea undergoes major structural transformations that ultimately determine tissue form and function. In this article, we will review corneal developmental dynamics from a structural perspective, consider the roles and interrelationships of collagens and proteoglycans, and comment on contemporary concepts and current challenges pertinent to developmental processes that result in an optically clear, mature cornea. Developmental Dynamics 237:2607,2621, 2008. © 2008 Wiley-Liss, Inc. [source] Diabetes care in childhood and adolescenceDIABETIC MEDICINE, Issue 2002P. R. Betts Abstract The presentation of diabetes in young people has changed significantly over recent years. Not only has there been a rising incidence of Type 1 diabetes, especially in young children, but also there is an increasing recognition of Type 2 diabetes. Young people are also increasingly being diagnosed with genetic defects of B-cell function and with diabetes in association with cystic fibrosis and other chronic diseases. There have also been significant changes in the pattern of paediatric diabetes care. This is increasingly being provided by a specialized paediatric multidisciplinary team in each health district working to agreed national standards. Despite improvements, diabetes control is still suboptimal with a high incidence of complications being reported in young adults. The challenge over the next few years is the provision of a uniform, equitable and first class paediatric service throughout the UK together with the introduction of new approaches to care, aiming to improve individual diabetic control and reduce long-term complications. Increased collaboration with adult colleagues is needed to enable the transition of care in adolescence to a service that young adults perceive to meet their needs, encourage their attendance and improve their diabetes control and quality of life. A national paediatric diabetes register together with regular audit will encourage these objectives. [source] Heterogeneity, speciation/extinction history and climate: explaining regional plant diversity patterns in the Cape Floristic RegionDIVERSITY AND DISTRIBUTIONS, Issue 3 2002R. M. Cowling Abstract. This paper investigates the role of heterogeneity and speciation/extinction history in explaining variation in regional scale (c. 0.1,3000 km2) plant diversity in the Cape Floristic Region of south-western Africa, a species- and endemic-rich biogeographical region. We used species-area analysis and analysis of covariance to investigate geographical (east vs. west) and topographic (lowland vs. montane) patterns of diversity. We used community diversity as a surrogate for biological heterogeneity, and the diversity of naturally rare species in quarter degree squares as an indicator of differences in speciation/extinction histories across the study region. We then used standard statistical methods to analyse geographical and topographic patterns of these two measures. There was a clear geographical diversity pattern (richer in the west), while a topographic pattern (richer in mountains) was evident only in the west. The geographical boundary coincided with a transition from the reliable winter-rainfall zone (west) to the less reliable non-seasonal rainfall zone (east). Community diversity, or biological heterogeneity, showed no significant variation in relation to geography and topography. Diversity patterns of rare species mirrored the diversity pattern for all species. We hypothesize that regional diversity patterns are the product of different speciation and extinction histories, leading to different steady-state diversities. Greater Pleistocene climatic stability in the west would have resulted in higher rates of speciation and lower rates of extinction than in the east, where for the most, Pleistocene climates would not have favoured Cape lineages. A more parsimonious hypothesis is that the more predictable seasonal rainfall of the west would have favoured non-sprouting plants and that this, in turn, resulted in higher speciation and lower extinction rates. Both hypotheses are consistent with the higher incidence of rare species in the west, and higher levels of beta and gamma diversity there, associated with the turnover of species along environmental and geographical gradients, respectively. These rare species do not contribute to community patterns; hence, biological heterogeneity is uniform across the region. The weak topography pattern of diversity in the west arises from higher speciation rates and lower extinction rates in the topographically complex mountains, rather than from the influence of environmental heterogeneity on diversity. [source] | ||||||||||||||||||||||||||||||||||||||||