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Specific Relationships (specific + relationships)
Selected AbstractsOntogenetic induced shifts in the ecology of sunbleak Leucaspius delineatus during early developmentJOURNAL OF FISH BIOLOGY, Issue 2005A. C. Pinder Using the non-native sunbleak Leucaspius delineatus as a model, the relationship between ontogeny and ecology was studied with a view to identifying specific morphological and physiological processes involved in influencing ecological niche shifts. Following a predefined saltatory model for the early ontogeny of sunbleak, field studies examined the temporal use of microhabitat, diet and morphological changes throughout early development. Following a dramatic shift in both morphology and ecology between the free embryo phase and the larval period, habitat use and diet showed little change during the larval period, with habitat use confined to marginal, vegetated areas and prey items associated with these habitats well represented in the diet. During the final larval step (L5), transition to the juvenile period resulted in the stabilization of relative growth, acquisition of the adult morphotype and was associated with a clear shift in diet and habitat use. During this period, sunbleak moved for the first time into open, deeper water, away from the banks, and utilized a similar range of food items to the adults. Specific relationships between form and function are further discussed. [source] Specific relationships between core beliefs and personality disorder symptoms in a non-clinical sampleCLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 2 2007Mark Reeves The current study examined the relationship of clinically relevant core beliefs measured by the Young Schema Questionnaire-Short Form (YSQ-SF) to personality disorder (PD) symptoms in a large non-clinical sample (N = 804). Results indicated that the 15 YSQ-SF scales added sizeable explained variance (4% to 13%) to self-reported symptoms of 12 PDs, above variance explained by gender and symptoms of other PDs. In addition, several specific core beliefs related uniquely to individual PDs after controlling for the other core beliefs. Given that core beliefs related to personality disorder symptoms in a non-clinical sample of people at the typical onset age of PDs, it is possible that such beliefs might be important to understanding the development of PDs.,Copyright © 2007 John Wiley & Sons, Ltd. [source] Fishery-induced demographic changes in the timing of spawning: consequences for reproductive success,FISH AND FISHERIES, Issue 3 2009Peter J. Wright Abstract Demography can have a significant effect on reproductive timing and the magnitude of such an effect can be comparable to environmentally induced variability. This effect arises because the individuals of many fish species spawn progressively earlier within a season and may produce more egg batches over a longer period as they get older, thus extending their lifetime spawning duration. Inter-annual variation in spawning time is a critical factor in reproductive success because it affects the early environmental conditions experienced by progeny and the period they have to complete phases of development. By reducing the average lifetime spawning duration within a fish stock, fishing pressure could be increasing the variability in reproductive success and reducing long-term stock reproductive potential. Empirical estimates of selection on birth date, from experiments and using otolith microstructure, demonstrate that there is considerable variation in selection on birth date both within a spawning season and between years. The few multi-year studies that have linked egg production with the survival of progeny to the juvenile stage further highlight the uncertainty that adults face in timing their spawning to optimize offspring survival. The production of many small batches of eggs over a long period of time within a season and over a lifetime is therefore likely to decrease variance and increase mean progeny survival. Quantifying this effect of demography on variability in survival requires a focus on lifetime reproductive success rather than year specific relationships between recruitment and stock reproductive potential. Modelling approaches are suggested that can better quantify the likely impact of changing spawning times on year-class strength and lifetime reproductive potential. The evidence presented strengthens the need to avoid fishing severely age truncated fish stocks. [source] A meta-analytic examination of the relationship between child sexual abuse and eating disordersINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 2 2002Linda Smolak Abstract Objective This study had two goals. The first was to assess the magnitude and consistency of the relationship between child sexual abuse (CSA) and eating disorders (ED). The second was to examine methodological factors contributing to the heterogeneity of this relationship. Method Meta-analysis was used to examine both questions. Fifty-three studies were included in the analysis. Results A small, significant positive relationship between CSA and ED emerged. The relationship was marked by heterogeneity. Effect sizes were largest when CSA was the grouping variable, the Eating Disorders Inventory (EDI) or the Eating Attitudes Test (EAT) was used as the measure of eating disorders, and nonclinical groups were compared with clinical samples. Discussion Models of CSA and ED need to more clearly specify what aspects of ED (e.g., body image or binge eating) are most influenced by which types of CSA. These specific relationships then need to be examined empirically. © 2002 by Wiley Periodicals, Inc. Int J Eat Disord 31: 136,150, 2002; DOI 10.1002/eat.10008 [source] UREASE GENE SEQUENCES FROM ALGAE AND HETEROTROPHIC BACTERIA IN AXENIC AND NONAXENIC PHYTOPLANKTON CULTURES,JOURNAL OF PHYCOLOGY, Issue 3 2009Kristopher M. Baker While urea has long been recognized as an important form of nitrogen in planktonic ecosystems, very little is known about how many or which phytoplankton and bacteria can use urea as a nitrogen source. We developed a method, targeting the gene encoding urease, for the direct detection and identification of ureolytic organisms and tested it on seven axenic phytoplankton cultures (three diatoms, two prymnesiophytes, a eustigmatophyte, and a pelagophyte) and on three nonaxenic Aureococcus anophagefferens Hargraves et Sieburth cultures (CCMP1784 and two CCMP1708 cultures from different laboratories). The urease amplicon sequences from axenic phytoplankton cultures were consistent with genomic data in the three species for which both were available. Seven of 12 phytoplankton species have one or more introns in the amplified region of their urease gene(s). The 63 urease amplicons that were cloned and sequenced from nonaxenic A. anophagefferens cultures grouped into 17 distinct sequence types. Eleven types were related to ,-Proteobacteria, including three types likely belonging to the genus Roseovarius. Four types were related to ,-Proteobacteria, including two likely belonging to the genus Marinobacter, and two types were related to ,-Proteobacteria. Terminal restriction fragment length polymorphism (TRFLP) analyses suggested that the sequenced amplicons represented approximately half of the diversity of bacterial urease genes present in the nonaxenic cultures. While many of the bacterial urease sequence types were apparently lab- or culture-specific, others were found in all three nonaxenic cultures, suggesting the possibility of specific relationships between these bacteria and A. anophagefferens. [source] Spin-echo MRI using ,/2 and , hyperbolic secant pulses,MAGNETIC RESONANCE IN MEDICINE, Issue 1 2009Jang-Yeon Park Abstract Frequency-modulated (FM) pulses have practical advantages for spin-echo experiments, such as the ability to produce a broadband , rotation, with an inhomogeneous radiofrequency (RF) field. However, such use leads to a nonlinear phase of the transverse magnetization, which is why FM pulses like the hyperbolic secant (HS) pulse are not commonly used for multislice spin-echo magnetic resonance imaging (MRI). Here, a general theory and methods are described for conventional spin-echo imaging using a , HS pulse for refocusing. Phase profiles produced by the HS pulse are analytically described. The analysis is extended to yield the specific relationships between pulse parameters and gradients, which must be satisfied to compensate the nonlinear phase variation produced with a spin-echo sequence composed of ,/2 and , HS pulses (the ,/2 HS , , HS sequence). The latter offers advantages for multislice spin-echo MRI, including excellent slice-selection and partial compensation for RF inhomogeneity. Furthermore, it can be implemented with a shorter echo time and lower power deposition than a previously described method using a pair of , HS pulses. Magn Reson Med 61:175,187, 2009. © 2008 Wiley-Liss, Inc. [source] Psychosocial outcomes at 15 years of children with a preschool history of speech-language impairmentTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 8 2006Margaret J. Snowling Background:, Evidence suggests there is a heightened risk of psychiatric disorder in children with speech-language impairments. However, not all forms of language impairment are strongly associated with psychosocial difficulty, and some psychiatric disorders (e.g., attention deficit/hyperactivity disorder (ADHD)) are more prevalent than others in language-impaired populations. The present study assessed the psychosocial adjustment in adolescence of young people with history of speech-language impairment, and investigated specific relationships between language deficits and psychiatric disorders. Methods:, Seventy-one young people (aged 15,16 years) with a preschool history of speech-language impairment were assessed using a psychiatric interview (K-SADS) supplemented by questionnaires probing social encounters and parental reports of behaviour and attention. Their psycho-social adjustment was compared with that of a cross-sectional control group of age-matched controls. Results:, Overall the rate of psychiatric disorder was low in the clinical sample and children whose language delay had resolved by 5.5 years had a good outcome. For those whose language difficulties persisted through the school years, there was a raised incidence of attention and social difficulties. These difficulties were partially independent and associated with different language profiles. The group with attention problems showed a profile of specific expressive language difficulties; the group with social difficulties had receptive and expressive language difficulties; and the group with both attention and social difficulties was of low IQ with global language difficulties. Conclusions:, Amongst children with speech-language delays at 5.5 years, those with more severe and persistent language difficulties and low nonverbal IQ are at higher risk of psychiatric morbidity in adolescence. [source] Giant submarine collapse of a carbonate platform at the Turonian,Coniacian transition: The Ayabacas Formation, southern PeruBASIN RESEARCH, Issue 3 2008Pierre Callot ABSTRACT The Ayabacas Formation of southern Peru is an impressive unit formed by the giant submarine collapse of the mid-Cretaceous carbonate platform of the western Peru back-arc basin (WPBAB), near the Turonian,Coniacian transition (,90,89 Ma). It extends along the southwestern edge of the Cordillera Oriental and throughout the Altiplano and Cordillera Occidental over >80 000 km2 in map view, and represents a volume of displaced sediments of >10 000 km3. The collapse occurred down the basin slope, i.e. toward the SW. Six zones are characterised on the basis of deformational facies, and a seventh corresponds to the northeastern ,stable' area (Zone 0). Zones 1,3 display increasing fragmentation from NE to SW, and are composed of limestone rafts and sheets embedded in a matrix of mainly red, partly calcareous and locally sandy, mudstones to siltstones. In contrast, in Zones 4 and 5 the unit consists only of displaced and stacked limestone masses forming a ,sedimentary thrust and fold system', with sizes increasing to the southwest. In Zone 6, the upper part of the limestone succession consists of rafts and sheets stacked over the regularly bedded lower part. The triggering of this extremely large mass wasting clearly ensued from slope creation, oversteepening and seismicity produced by extensional tectonic activity, as demonstrated by the observation of synsedimentary normal faults and related thickness variations. Other factors, such as pore pressure increases or lithification contrasts probably facilitated sliding. The key role of tectonics is strengthened by the specific relationships between the basin and collapse histories and two major fault systems that cross the study area. The Ayabacas collapse occurred at a turning point in the Central Andean evolution. Before the event, the back-arc basin had been essentially marine and deepened to the west, with little volcanic activity taking place at the arc. After the event, the back-arc was occupied by continental to near-continental environments, and was bounded to the southwest by a massive volcanic arc shedding debris and tuffs into the basin. [source] Spatial Distribution Patterns of Jumping Spiders Associated with Terrestrial BromeliadsBIOTROPICA, Issue 4 2004Gustavo Q. Romero ABSTRACT The jumping spiders Eustiromastix native, Psecas sumptuosus, and Uspachus sp. n. (Salticidae) live on terrestrial bro-meliads in areas with different phytophysiognomies in southeastern and northeastern Brazil. To understand these spider,plant interactions, we investigated if (1) these spiders were associated specifically with bromeliads, (2) the spiders utilized particular bromeliad species, and (3) plant size and density of bromeliads affected spider distribution. The jumping spiders were not found outside bromeliads, indicating a strict spider,plant association. Eustiromastix and Uspachus occupied bromeliads in open areas, whereas Psecas was found on forest bromeliads. Eustiromastix occurred at a higher frequency on larger bromeliads and in patches with higher bromeliad density. This is one of the few studies to demonstrate specific relationships between jumping spiders and a particular plant type. RESUMO As aranhas saltadoras Eustiromastix native, Psecas sumptuosus e Uspachus sp. n. (Salticidae) vivem sobre bromélias terrestres em áreas com diferentes fitofisionomias no sudeste e nordeste do Brasil. Para compreender estas interaçóes aranha-planta, nós investigamos se (1) estas aranhas estavam associadas especificamente a bromélias, (2) as aranhas utilizam espécies particulares de bromélias e (3) tamanho e densidade das bromélias afetam a distribuiçáo das aranhas. As aranhas saltadoras não foram encontradas fora das bromélias, indicando uma associaçáo estrita entre aranha e planta. Eustiromastix e Uspachus ocuparam bromelias em areas abertas enquanto Psecas foi encontrada em bromélias de floresta. Eustiromastix ocorreu em maior freqüéncia sobre bromélias maiores e em manchas com maior densidade de bromélias. Este estudo é um dos poucos a demonstrar relaço,es especificas entre aranhas saltadoras e um tipo particular de planta. [source] 2355: Biomechanical analysis of the pressure-volume relationship in a statically loaded human eyeACTA OPHTHALMOLOGICA, Issue 2010AA STEIN Purpose To develop an approach for estimating the mechanical characteristics of the individual eye in the ophthalmologic procedures based on static load application (tonometry, et al.). Methods The fibrous coat is mathematically modeled as a soft elastic shell (cornea) connected with an elastic system that mainly consists of the sclera and is characterized by a single elastic constant describing its response to the intraocular pressure. A function representing the intraocular volume as a function of two variables, the intraocular pressure and the load applied, called the volume function is introduced. This function is then specified on the basis of a simple model characterized by two elastic constants in the case of an applanating load. Results A general method of estimating the integral elastic behavior of the individual eye is developed and specific relationships between elastic constants important in different loading processes are obtained. Conclusion The method developed makes it possible to reliably estimate the integral elastic behavior of the fibrous coat and, as a result, to obtain more correct data on the intraocular pressure and other mechanical characteristics. Although in different loading processes (for example, in tonometry and inflating the eye by a liquid volume) different integral elastic contacts are involved, the model proposed provides a means for obtaining efficient approximate relationships between these constants. [source] | |||||||||||||||||||