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Growth Analysis (growth + analysis)
Selected AbstractsOriented Grain Growth Analyses With In Situ Annealing Experiments Using High Energy Synchrotron RadiationADVANCED ENGINEERING MATERIALS, Issue 3 2010Caterina Elisabetta Tommaseo The development of the recrystallization and annealing textures of Al,Mn alloys with 0.4, 0.7 and 1,wt.-% manganese is analyzed using specific techniques that allow the detection of changes in grain orientation during in situ annealing. In order to investigate the evolution of texture components during annealing, highly rolled samples were annealed from room temperature to 500,°C at a constant heating rate. The advantage of in situ annealing experiments using synchrotron radiation is the detection of grain orientations over time, which allows observation of the development of the recrystallization and annealing textures in a sample. In fact, the recrystallization and annealing textures in the Al,0.4Mn are characterized by an interruption in the detection of most of the grain orientations between 380 and 425,°C and by competition between the cube {001}<100>, {011}<1-33>, {011}<0-11> and rotated-cube {001}<110> grain orientations, where the latter is detected until the end of the experiment. In the Al,0.7Mn sample a competition between the cube {001}<100>, {011}<100>, and rotated cube {001}<110>, {011}<0,11> grain orientations is observed. In the sample with the highest manganese concentration (1,wt.-%) an unhindered grain growth of all possible grain orientations with a high amount of the {011}<0-11> grain orientation is observed. The evolution of the resulting local textures is discussed in terms of preferentially oriented grain growth depending on the temperature and manganese concentration. [source] A developmental typology of adolescent personalityEUROPEAN JOURNAL OF PERSONALITY, Issue 4 2010Theo A. Klimstra Abstract The purpose of the current study is to examine whether Block's personality types (i.e. Resilients, Undercontrollers and Overcontrollers) are replicable as developmental trajectories. We applied a Latent Class Growth Analysis (LCGA) framework to five- annual-wave data on a sample of early to middle adolescents (n,=,923). Our results showed that Block's Resilients, Undercontrollers and Overcontrollers are indeed replicable as developmental trajectories across adolescence. These developmental types were related to problem behaviour in a similar way as types found in studies using cross-sectional data. As such, Resilients reflected low levels of problem behaviour, Undercontrollers had high levels of delinquency and Overcontrollers had high levels of depression. Implications and suggestions for further research are discussed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Increased growth and recruitment of piscivorous perch, Perca fluviatilis, during a transient phase of expanding submerged vegetation in a shallow lakeFRESHWATER BIOLOGY, Issue 12 2005ANDERS HARGEBY Summary 1. In this study, we examine how a 7-year period of expanding submerged stonewort (Chara spp.) vegetation during a shift from turbid to clear water in a shallow lake influenced individual growth and population size structure of perch (Perca fluviatilis). We expected that a shift from phytoplankton to macrophyte dominance and clear water would improve feeding conditions for perch during a critical benthivorous ontogenetic stage, and enhance the recruitment of piscivorous perch. 2. Growth analysis based on opercula showed that growth during the second year of life was significantly higher in years with abundant vegetation than in years with turbid water and sparse vegetation. Growth was not affected during the first, third and fourth year of life. Stable isotope analyses on opercula from 2-year-old perch showed that the increase in growth coincided with a change in carbon source in the diet. Stable nitrogen ratio did not change, indicating that the increased growth was not an effect of any change in trophic position. 3. Following the expansion of submerged vegetation, perch size range and abundance of piscivorous perch increased in central, unvegetated areas of the lake. In stands of stoneworts, however, mainly benthivorous perch were caught, and size range did not change with time. 4. Our findings provide empirical support for the notion that establishment of submerged vegetation may lead to increased recruitment of piscivorous perch, because of improved competitive conditions for perch during the benthivorous stage. This is likely to constitute a benthic-pelagic feedback coupling, in which submerged vegetation and clear water promote the recruitment of piscivorous perch, which, in turn, may increase water clarity through top-down effects in the pelagic. [source] Growth analysis of a patient with ectodermal dysplasia treated with endosseous implants: 6-year follow-upJOURNAL OF ORAL REHABILITATION, Issue 3 2006T. ALCAN summary, The purpose of this article is to report the clinical course and 6-year follow-up of a child with ectodermal dysplasia who was treated with implants surgery very early. This article reports placement of mandibular endosseous implants in a 4-year-old patient with hypohidrotic ectodermal dysplasia and oligodontia. This congenital anomaly does not appear to retard healing and the osseointegration remains after 6 years and 3 months of loading. Mandibular and maxillary skeletal growth and development was normal. However, because of lack of alveolar growth, in time, patient's vertical growth pattern changed to low angle. This could be corrected by changing the vertical heights of the abutment and prosthesis. As a result, in ectodermal dysplasias cases with anadontia, early implant placement and fixed prosthesis could be a good multidisciplinary treatment option for poor cooperative child. [source] Growth and mortality of prairie stream fishes: relations with fish community and instream habitat characteristicsECOLOGY OF FRESHWATER FISH, Issue 2 2001M. C. Quist Abstract , Few studies have been conducted to describe the age structure, growth rates and mortality of fishes in small stream ecosystems. The purpose of this study was therefore to determine age structure, growth rates and mortality (i.e., total annual mortality and, age-specific mortality) of central stonerollers Campostoma anomalum, creek chubs Semotilus atromaculatus, red shiners Cyprinella lutrensis and green sunfish Lepomis cyanellus from 13 streams on Fort Riley Military Reservation, Kansas, using incremental growth analysis. Further, we were interested in determining the influence of fish community and instream habitat characteristics on growth rates. The age structure of central stonerollers, creek chubs, and red shiners was dominated by young individuals (i.e., less than age 2); however, over 60% of the green sunfish were age 2 to age 4. Mean total annual mortality was >60% for cyprinids and averaged approximately 44% for green sunfish. The age-specific mortality of central stonerollers and red shiners was generally less than 45% between age 0 and 1 and increased to over 85% for fishes greater than age 1. Fish community characteristics (e.g., catch per unit effort of trophic guilds) and chemical habitat (e.g., total phosphorous) were not related to growth rates (P>0.05). Growth of central stonerollers was not significantly correlated with physical habitat (P>0.05). However, the growth increments of creek chubs, red shiners, and green sunfish were related to the amount of woody debris (e.g., total woody debris, log complex habitat; r>0.60; P,0.05). The results of this study provide important information on the population dynamic rate functions of cyprinid and green sunfish populations in small prairie streams. Furthermore, these data suggest that woody debris is important habitat influencing growth of stream fishes., [source] Prediction of crack opening stress levels for 1045 quenched and tempered steel under service loading spectraFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 1 2006M. KHALIL ABSTRACT The opening stresses of a crack emanating from an edge notch in a 1045 quenched and tempered steel specimen were measured under two different Society of Automotive Engineers (SAE) standard service load histories having different average mean stress levels. The two spectra are the Grapple Skidder history (GSH), which has a positive average mean stress, and the Log Skidder history (LSH), which has a zero average mean stress. To capture the behaviour of the crack opening stress in the material, the crack opening stress levels were measured at 900X using an optical video microscope, at frequent intervals for each set of histories scaled to two different maximum stress ranges. A crack growth analysis based on a fracture mechanics approach was used to model the fatigue behaviour of the steel specimens for the given load spectra and stress ranges. Crack growth analysis was based on an effective strain-based intensity factor, a crack growth rate curve obtained during closure-free loading cycles and a local notch strain calculation based on Neuber's rule. The crack opening stress (Sop) was modelled and the model was implemented in a fatigue notch model, and the fatigue lives of the specimens under the two different spectra scaled to several maximum stress levels were estimated. The average measured crack opening stresses were between 6 and 12% of the average calculated crack opening stresses. In the interest of simplifying the use of Sop in design, the average Sop was correlated with the frequency of occurrence of the cycle reducing the Sop to the average crack opening stress level. The use of an Sop level corresponding to the cycle causing a reduction in Sop to a level reached once per 10 cycles gave a conservative estimate of average crack opening stress for all the histories. [source] Do shade-tolerant tropical tree seedlings depend longer on seed reserves?FUNCTIONAL ECOLOGY, Issue 4 2002Functional growth analysis of three Bignoniaceae species Summary 1.,A functional growth analysis was used to determine the duration of strict dependency on seed reserves for energy and nitrogen in three woody Bignoniaceae species (Tabebuia rosea DC., Challichlamys latifolia K. Schum. and Pithecoctenium crucigerum A. Gentry) which differed in cotyledon function (photosynthetic, semi-photosynthetic and storage) and shade tolerance (probability of seedling establishment and survival in the understorey). 2.,Seedlings were raised from seeds in sand culture under combinations of three nitrogen levels (daily supply of nutrient solution containing 100, 10 and 0% of 2·6 mm N) and two irradiances (27 and 1% full sun). Time course of biomass, non-cotyledonous biomass and leaf area for 40 days post-germination were compared to identify when the external availability of nitrogen or light began to affect seedling growth. 3.,Seedlings of all species became dependent on external energy supply earlier than they did on nitrogen supply. In all species seed nitrogen was sufficient to support positive seedling growth for 40 days in shade, but not in sun. 4.,Tabebuia rosea with photosynthetic cotyledons responded to light availability earlier than more shade-tolerant species with storage cotyledons. Challichlamys latifolia, the most shade-tolerant species, had the highest nitrogen concentration in seeds and was the last to respond to external nitrogen availability. Thus seedlings of the most shade-tolerant species depended on seed reserves for the longest period for both energy and nitrogen. 5.,Relative growth rate after seedlings initiated autotrophic growth was in a trade-off relationship with seedling survivorship in the understorey across the three species. Tabebuia rosea, the least shade-tolerant species, had the highest positive net carbon balance in sun and shade. 6.,Functional morphology of cotyledons and concentration of seed nitrogen deserve as much attention as seed size as correlates of contrasting seedling regeneration strategies. [source] On the measurement of growth with applications to the modelling and analysis of plant growthFUNCTIONAL ECOLOGY, Issue 2 2000Roderick M. L. Abstract 1.,In this paper, a theoretical framework for the analysis of growth is described. Growth is equated with change in volume (V) and the growth rate is given by the equation; dV/dt = (dm/dt)(1/,) , (d,/dt)(m/,2) where m is the mass and , the density. The volume is inclusive of internal air spaces. 2.,The second term of the growth equation (see above) can be ignored if density is constant over time. Data for humans (and presumably other large animals) show that while composition changes over time, the density is approximately constant at about that of water. In that case, the growth rate can be estimated from measures of the rate of change of mass. However, the density of plants is variable (c. 0·4,1·2 g cm,3) and measures of mass and density are necessary to analyse plant growth. 3.,To use the theory as the basis of plant growth models, it is necessary to develop simple methods for estimating the surface area of roots, stems and leaves assuming that the mass and volume are known. A literature review found that the surface area to volume ratios of leaves and roots generally increase with the mass concentration of water. Theoretical arguments are used to predict that in woody stems, the situation should be reversed such that the surface area to volume ratio increases with the mass concentration of dry matter. Those relationships should be very useful in the development of plant growth models. 4.,Measures of plant dry mass and estimates of the rate of change in dry mass are shown to be very difficult to interpret because of differences in the mass concentration of dry matter between individuals and over time. 5.,It is concluded that measures of mass and density will be necessary before plant growth analysis can achieve its full potential. A framework for extending the theory to include the forces necessary for growth to occur is described. [source] Lack of functional erythropoietin receptors of cancer cell linesINTERNATIONAL JOURNAL OF CANCER, Issue 5 2008Magdalena Laugsch Abstract Erythropoietin (Epo) therapy reduces red cell transfusion requirements and improves the quality of life of anemic cancer patients receiving chemotherapy. However, there is concern that Epo may promote tumor growth. We investigated by real-time RT-PCR, immunofluorescence microscopy, Western blotting and cell growth analysis whether human cancer cell lines (SH-SY5Y, MCF7, HepG2, U2-OS, HeLa, HEK293T, RCC4, HCT116, 7860wt and SW480) possess functional Epo receptors (EpoR). We detected EpoR mRNA in all cell lines. Neither hypoxia nor Epo treatment altered the level of EpoR mRNA expression. Four commonly used commercial antibodies proved to be unsuitable for immunoblot procedures because they cross-reacted with several proteins unrelated with EpoR. Depending on the antibody used, EpoR was localized to the plasma membrane, the cytoplasm or the nucleus. Experiments with small interfering RNA showed that EpoR protein was not expressed by the tumor cells except by UT7/Epo leukemia cells, which served as an EpoR positive control line, and by cells transfected with the human EpoR gene. Apart from UT7/Epo, none of the tumor cell lines responded to Epo treatment with phosphorylation of signaling molecules or with cell proliferation. © 2007 Wiley-Liss, Inc. [source] Effects of physical and verbal aggression, depression, and anxiety on drinking behavior of married partners: a prospective and retrospective longitudinal examinationAGGRESSIVE BEHAVIOR, Issue 4 2009Margaret K. Keiley Abstract In an ethnically diverse sample of 195 married couples, we conducted a latent factor growth analysis to investigate the longitudinal link (4 time points over 4½ years) between marital aggression (physical and verbal aggression self- and partner-reports) and individual internalizing symptoms (depression and anxiety) as they relate to trajectories of alcohol use among husbands and wives. Alcohol use was operationalized as a latent factor with self- and partner reports of problem drinking as measured by the Michigan Alcoholism Screening Test and the Alcohol Dependence Scale. Verbal aggression by husbands or wives, by itself, has no effect on their alcohol use over time. In conjunction with depression, however, verbally aggressive husbands do have elevated drinking levels. The effects of husbands' and wives' physical aggression on their own and their partners' drinking behavior were also significant. This study is one of the first to examine the change over time in alcohol use for marital partners as related to marital aggression and internalizing symptoms. Our results shed light on areas of marital functioning (aggression, internalizing, alcohol use) that have not been investigated in conjunction with each other in a longitudinal design. Aggr. Behav. 35:296,312, 2009. © 2009 Wiley-Liss, Inc. [source] Retrospective growth analysis of Atlantic salmon Salmo salar and implications for abundance trendsJOURNAL OF FISH BIOLOGY, Issue 10 2010F. Hogan Scale archives of Atlantic salmon Salmo salar from Maine, U.S.A., were examined to determine whether ocean conditions affected the long-term trends in S. salar populations in the southern tier of the species' range in North America. To date, scale analyses of southern tier populations have been limited to hatchery fish; previous studies suggest that post-smolt growth does not influence recruitment, with the exception that winter growth may play a role in stock maturation rate. A time series of scales from the Machias and Narraguagus Rivers spanning the years 1946 to 1999 was analysed. Image analysis was used to measure intercirculi spacing, which provided proxy variables of growth rate. Post-smolt growth increment has increased since the early 1990s, as returns have decreased, suggesting that survival factors act on post-smolts independent of growth. The data support the hypothesis of a decoupling between freshwater size and early marine growth. Growth during the second sea winter was independent of post-smolt growth, suggesting that individuals are capable of significant compensatory growth. Southern tier North American stocks exhibit a similar pattern of independence between growth and survival as observed for northern tier North American stocks. These data support the inference that the recruitment of the North American and European subspecies is governed by fundamentally different mechanisms. [source] Heterogeneity in the course of posttraumatic stress disorder: Trajectories of symptomatology,JOURNAL OF TRAUMATIC STRESS, Issue 3 2010Benjamin D. Dickstein Unconditional and conditional trajectories of posttraumatic stress disorder (PTSD) symptomatology were examined using a sample of U.S. soldiers deployed on a NATO-led peacekeeping mission to Kosovo. Data were collected at 4 time points, ranging from the weeks leading up to deployment to 9-months postdeployment. Latent class growth analysis revealed 4 unique symptom trajectories: resilience, recovery, delayed, and unrealized anxiety. Variables identified as significant predictors of trajectory class included previous traumatic events, combat exposure, peacekeeping daily hassles, depression, alcohol use, aggressive behavior, stress reactivity, and military rank. Results from this study add to the literature detailing the variability in PTSD course, as well as to the literature pertaining to predictors of PTSD onset and course. [source] On Cauchy estimates and growth orders of entire solutions of iterated Dirac and generalized Cauchy,Riemann equationsMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 14 2006D. Constales Abstract In this paper, we study the growth behaviour of entire Clifford algebra-valued solutions to iterated Dirac and generalized Cauchy,Riemann equations in higher-dimensional Euclidean space. Solutions to this type of systems of partial differential equations are often called k -monogenic functions or, more generically, polymonogenic functions. In the case dealing with the Dirac operator, the function classes of polyharmonic functions are included as particular subcases. These are important for a number of concrete problems in physics and engineering, such as, for example, in the case of the biharmonic equation for elasticity problems of surfaces and for the description of the stream function in the Stokes flow regime with high viscosity. Furthermore, these equations in turn are closely related to the polywave equation, the poly-heat equation and the poly-Klein,Gordon equation. In the first part we develop sharp Cauchy-type estimates for polymonogenic functions, for equations in the sense of Dirac as well as Cauchy,Riemann. Then we introduce generalizations of growth orders, of the maximum term and of the central index in this framework, which in turn then enable us to perform a quantitative asymptotic growth analysis of this function class. As concrete applications we develop some generalizations of some of Valiron's inequalities in this paper. Copyright © 2006 John Wiley & Sons, Ltd. [source] ENDOGENOUS GROWTH, PRICE STABILITY AND MARKET DISEQUILIBRIAMETROECONOMICA, Issue 1 2010Orlando Gomes ABSTRACT Resorting to an endogenous growth framework, the paper studies the implications of taking market clearing as a long-term possibility rather than an every period implicit assumption, as in conventional growth analysis. The underlying main assumption respects to an adjustment mechanism in which: (1) transitional dynamics are characterized by the persistence of an accumulated market imbalance, and (2) monetary authorities are able to guarantee price stability. The implications of this modeling structure are the following: (1) a market-clearing equilibrium may co-exist with other equilibrium points, (2) several types of stability outcomes are obtainable, and (3) monetary policy becomes relevant for growth. 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