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Developmental Data (developmental + data)
Selected AbstractsSelection for discontinuous life-history traits along a continuous thermal gradient in the butterfly Aricia agestisECOLOGICAL ENTOMOLOGY, Issue 6 2005Steve Burke Abstract., 1.,Voltinism may be conceptualised as the product of development rate and the timing of diapause , two components that together translate gradual environmental variation, through periods of growth and development, into ,generational units'. This may result in very different selection pressures on diapause induction and development time in populations with different numbers of generations per year. 2.,Developmental data from univoltine and bivoltine populations of the butterfly Aricia agestis (Lepidoptera: Lycaenidae) in North Wales were used to examine larval development time and the timing of diapause, and their contribution towards voltinism in populations that occur at the same latitude and in geographic proximity to one another along a thermal gradient. 3.,The critical photoperiod for diapause induction in univoltines and bivoltines from the same latitude differed by more than 1.5 h. 4.,Development time also differed significantly between these populations, in line with predictions that bivoltines would need to exhibit shorter development times in order to achieve two complete generations per year. Shorter development times for bivoltines result in lower pupal weights, suggesting a trade-off exists between generation number and body size that may dictate the position of the transition zone between the two life-history strategies. Analysis of development times in a third population, from southern England, with greater thermal availability than those from North Wales, further supports this hypothesised trade-off. 5.,To achieve the conversion of a continuous thermal gradient into the binary biological response from univoltism to bivoltism, bivoltines speed up development, reduce adult body size and shift their diapause induction response. [source] Infant developmental milestones and subsequent cognitive functionANNALS OF NEUROLOGY, Issue 2 2007Graham K. Murray MD Objective Developmental delay is associated with a subsequent diagnosis of learning disability. However, the relationship between the age of reaching infant developmental milestones and later intellectual function within the general population remains unresolved. We hypothesized that earlier attainment of developmental milestones would be associated with better subsequent intellectual performance throughout the range of abilities, rather than confined to extremes. Methods Developmental data were obtained at age 2 years in the National Survey of Health and Development, a representative sample of 5,362 children born in the United Kingdom in 1946. Data on intellectual function and educational attainment at ages 8, 26, and 53 years were also obtained. Multiple linear regression and logistic regression were used to analyze the effect of age of reaching developmental milestones on subsequent cognition and educational attainment. Results The age of reaching developmental milestones was associated with intellectual performance at ages 8, 26, and 53 years; for every month earlier a child learned to stand, there was, on average, a gain of one half of one intelligence quotient point at age 8. Speech development had a small but statistically significant effect on subsequent educational attainment (later developers were less likely to progress beyond basic education); this effect was not apparent for motor development. Effect sizes were reduced when the slowest developers were excluded, but many effects remained significant. Interpretation The association between later development and poorer subsequent intellectual function is small, but it does have theoretical implications; we suggest it is secondary to suboptimal cortical-subcortical connectivity. Ann Neurol 2007 [source] Perplexing Pax: From puzzle to paradigmDEVELOPMENTAL DYNAMICS, Issue 10 2008Judith A. Blake Abstract Pax transcription factors are critical for the development of the central nervous system (CNS) where they have a biphasic role, initially dictating CNS regionalization, while later orchestrating differentiation of specific cell subtypes. While a plethora of expression, misexpression, and mutation studies lend support for this argument and clarify the importance of Pax genes in CNS development, less well understood, and more perplexing, is the continued Pax expression in the adult CNS. In this article we explore the mechanism of action of Pax genes in general, and while being cognizant of existing developmental data, we also draw evidence from (1) adult progenitor cells involved in regeneration and tissue maintenance, (2) specific expression patterns in fully differentiated adult cells, and (3) analysis of direct target genes functioning downstream of Pax proteins. From this, we present a more encompassing theory that Pax genes are key regulators of a cell's measured response to a dynamic environment. Developmental Dynamics 237:2791,2803, 2008. © 2008 Wiley-Liss, Inc. [source] Neurodevelopmental outcomes in children with HIV infection under 3 years of ageDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2006C J Foster BA MBBS MRCPCH Following the introduction of combination antiretroviral therapy, children vertically infected with the human immunodeficiency virus (HIV-1) living in the developed world are surviving into adult life. This paper reviews the neurodevelopmental outcomes of 62 consecutively-presenting children with HIV-1 infection diagnosed before 3 years of age (32 males, 30 females; median age at presentation 6mo). Neurological and developmental data are presented with immunological and virological responses to antiretroviral therapy. Fourteen children (22%) had abnormal neurological signs and 25 (40%) demonstrated significant developmental delay on standardized developmental assessments. Children presenting with more severe HIV-1 disease and immune compromise had significantly more abnormal neurological signs and developmental delays than children presenting with milder HIV-1 symptomatology. Immune function, control of HIV-1 viral replication, and growth parameters improved with antiretroviral therapy (median age at last follow-up 7y 3mo); however, abnormal neurological signs and significant gross motor difficulties persisted. [source] Prediction of mortality at age 40 in Danish males at high and low risk for alcoholismACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2004J. Knop Objective:, This prospective high-risk study examined the influence of father's alcoholism and other archival-generated measures on premature death. Method:, Sons of alcoholic fathers (n = 223) and sons of non-alcoholic fathers (n = 106) have been studied from birth to age 40. Archival predictors of premature death included father's alcoholism, childhood developmental data, and diagnostic information obtained from the Psychiatric Register and alcoholism clinics. Results:, By age 40, 21 of the 329 subjects had died (6.4%), a rate that is more than two times greater than expected. Sons of alcoholic fathers were not more likely to die by age 40. Premature death was associated with physical immaturity at 1-year of age and psychiatric/alcoholism treatment. No significant interactions were found between risk and archival measures. Conclusion:, Genetic vulnerability did not independently predict death at age 40. Death was associated with developmental immaturities and treatment for a psychiatric and/or substance abuse problem. [source] Occurrence and distribution of sesamoid bones in squamates: a comparative approachACTA ZOOLOGICA, Issue 3 2010Adriana Jerez Abstract Jerez, A., Mangione, S. and Abdala, V. 2010. Occurrence and distribution of sesamoid bones in squamates: a comparative approach.,Acta Zoologica (Stockholm) 91: 295,305 Sesamoids are defined as skeletal elements that develop within a continuous band of regular dense connective tissue (tendon or ligament) adjacent to an articulation or joint. In this work, we discuss developmental data on two squamate species, provide data on the onset of the squamate sesamoids and the muscles they are associated to. Our results show that Mabuya mabouya and Liolaemus albiceps exhibited rather similar ontogenetic patterns and that the first sesamoids appear in embryos. The ossifying sesamoid timing is different between M. mabouya and L. albiceps, being faster in the former. In adults, we found 41 sesamoids, considering both fore and hindlimbs. We did not find any intrataxonomic differences, or any differences between the right and left side of the specimens in relation to the sesamoid presence. We recognize four types of sesamoids: (1) embedded sesamoids; (2) interosseus sesamoids; (3) glide sesamoids; and (4) supporting sesamoids. A table is included with a preliminary survey of the sesamoid distribution pattern in 10 Squamate clades. [source] Agnathan brain anatomy and craniate phylogenyACTA ZOOLOGICA, Issue 2009Roman Hossein Khonsari Abstract The central nervous system of hagfishes displays unique characteristics that are distinct from any other craniate neuroanatomic features. Whether these hagfish characters are general for all craniates, autapomorphies of hagfishes, or merely a derived state of the general cyclostome condition is still a matter of debate that relates to the question of the monophyly or paraphyly of the cyclostomes. The present cladistic study includes 123 neuroanatomical characters of nine chordate species and supports cyclostome paraphyly, in contrast to most current molecular sequence-based phylogenies, which support cyclostome monophyly. An understanding of the unique neural characters in hagfishes is critical to inspiring further comparative and developmental studies with regards to these two conflicting results and the very deep divergence between craniates and their presumed sister groups. The recent access to hagfish developmental data may provide exciting perspectives in the understanding and characterization of the basalmost craniate node and the interpretation of hagfish brain structure. [source] The origin of the endothelial cells: an evo-devo approach for the invertebrate/vertebrate transition of the circulatory systemEVOLUTION AND DEVELOPMENT, Issue 4 2005R. Muñoz-Chápuli Summary Circulatory systems of vertebrate and invertebrate metazoans are very different. Large vessels of invertebrates are constituted of spaces and lacunae located between the basement membranes of endodermal and mesodermal epithelia, and they lack an endothelial lining. Myoepithelial differentation of the coelomic cells covering hemal spaces is a frequent event, and myoepithelial cells often form microvessels in some large invertebrates. There is no phylogenetic theory about the origin of the endothelial cells in vertebrates. We herein propose that endothelial cells originated from a type of specialized blood cells, called amoebocytes, that adhere to the vascular basement membrane. The transition between amoebocytes and endothelium involved the acquisition of an epithelial phenotype. We suggest that immunological cooperation was the earliest function of these protoendothelial cells. Furthermore, their ability to transiently recover the migratory, invasive phenotype of amoebocytes (i.e., the angiogenic phenotype) allowed for vascular growth from the original visceral areas to the well-developed somatic areas of vertebrates (especially the tail, head, and neural tube). We also hypothesize that pericytes and smooth muscle cells derived from myoepithelial cells detached from the coelomic lining. As the origin of blood cells in invertebrates is probably coelomic, our hypothesis relates the origin of all the elements of the circulatory system with the coelomic wall. We have collected from the literature a number of comparative and developmental data supporting our hypothesis, for example the localization of the vascular endothelial growth factor receptor-2 ortholog in hemocytes of Drosophila or the fact that circulating progenitors can differentiate into endothelial cells even in adult vertebrates. [source] Gene expression and digit homology in the chicken embryo wingEVOLUTION AND DEVELOPMENT, Issue 1 2005Monique C. M. Welten Summary The bird wing is of special interest to students of homology and avian evolution. Fossil and developmental data give conflicting indications of digit homology if a pentadactyl "archetype" is assumed. Morphological signs of a vestigial digit I are seen in bird embryos, but no digit-like structure develops in wild-type embryos. To examine the developmental mechanisms of digit loss, we studied the expression of the high-mobility group box containing Sox9 gene, and bone morphogenetic protein receptor 1b (bmpR-1b),markers for precondensation and prechondrogenic cells, respectively. We find an elongated domain of Sox9 expression, but no bmpR-1b expression, anterior to digit II. We interpret this as a digit I domain that reaches precondensation, but not condensation or precartilage stages. It develops late, when the tissue in which it is lodged is being remodeled. We consider these findings in the light of previous Hoxd-11 misexpression studies. Together, they suggest that there is a digit I vestige in the wing that can be rescued and undergo development if posterior patterning cues are enhanced. We observed Sox9 expression in the elusive "element X" that is sometimes stated to represent a sixth digit. Indeed, incongruity between digit domains and identities in theropods disappears if birds and other archosaurs are considered primitively polydactyl. Our study provides the first gene expression evidence for at least five digital domains in the chick wing. The failure of the first to develop may be plausibly linked to attenuation of posterior signals. [source] Notes on the development and behaviour of two Binturong Arctictus binturong litters born at Taronga Zoo, SydneyINTERNATIONAL ZOO YEARBOOK, Issue 1 2010L. ABRA Binturongs Arctictus binturong have been maintained at Taronga Zoo, Sydney, Australia, since 1958 and the species bred there for the first time in 1962. In 2005, an unrelated pair were acquired from Singapore Zoo with the intention of establishing a breeding pair. A new purpose-built facility was constructed with suitable space and climbing opportunities. The Binturong pair underwent an introduction programme and they first mated 4 weeks after the initial introduction. A birth plan was formulated, which included the installation of surveillance cameras and not separating the , from the ,. In 2007, two litters of cubs [0.1 and 2.1 (,.,)] were born and developmental data were collected. The data were reviewed and, based on four shared categories, were evaluated and discussed. [source] Development of the cypriniform protrusible jaw complex in Danio rerio: Constructional insights for evolutionJOURNAL OF MORPHOLOGY, Issue 7 2010Katie Lynn Staab Abstract Studies on the evolution of complex biological systems are difficult because the construction of these traits cannot be observed during the course of evolution. Complex traits are defined as consisting of multiple elements, often of differing embryological origins, with multiple linkages integrated to form a single functional unit. An example of a complex system is the cypriniform oral jaw apparatus. Cypriniform fishes possess an upper jaw characterized by premaxillary protrusion during feeding. Cypriniforms effect protrusion via the kinethmoid, a synapomorphy for the order. The kinethmoid is a sesamoid ossification suspended by ligaments attaching to the premaxillae, maxillae, palatines, and neurocranium. Upon mouth opening, the kinethmoid rotates as the premaxillae move anteriorly. Along with bony and ligamentous elements, there are three divisions of the adductor mandibulae that render this system functional. It is unclear how cypriniform jaws evolved because although the evolution of sesamoid elements is common, the incorporation of the kinethmoid into the protrusible jaw results in a function that is atypical for sesamoids. Developmental studies can show how biological systems are assembled within individuals and offer clues about how traits might have been constructed during evolution. We investigated the development of the protrusible upper jaw in zebrafish to generate hypotheses regarding the evolution of this character. Early in development, the adductor mandibulae arises as a single unit. The muscle divides after ossification of the maxillae, on which the A1 division will ultimately insert. A cartilaginous kinethmoid first develops within the intermaxillary ligament; it later ossifies at points of ligamentous attachment. We combine our structural developmental data with published kinematic data at key developmental stages and discuss potential functional advantages in possessing even the earliest stages of a system for protrusion. J. Morphol. 2010. © 2010 Wiley-Liss, Inc. [source] Temperature-dependent development of the parasitoid Tachinaephagus zealandicus on five forensically important carrion fly speciesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2010S. C. VOSS The influences of temperature and host species on the development of the forensically important parasitoid Tachinaephagus zealandicus Ashmead (Hymenoptera: Encyrtidae) were studied at six constant temperatures in the range of 15,30°C. T. zealandicus completed development successfully between 15°C and 27°C on five species of Calliphoridae, Calliphora albifrontalis Malloch, Calliphora dubia Macquart, Lucilia sericata Meigen, Chrysomya rufifacies Macquart and Chrysomya megacephala Fabricius. No adult parasitoids emerged from any of the host species reared at 30°C. Temperature and host species significantly influenced development time, emergence success and progeny size. Development was significantly longer on Ch. megacephala and Ch. rufifacies at 18,24°C and significantly longer on Ch. rufifacies and C. albifrontalis at 15°C and 27°C. Parasitoid emergence success was greatest at 21°C, declined at the temperature extremes (15°C and 27°C) and was significantly lower on Ch. megacephala and Ch. rufifacies than on the three other host species. Progeny numbers per host pupa were highest at 21,24°C, declined on either side of this temperature range and were significantly lower on L. sericata, Ch. rufifacies and Ch. megacephala than on either C. dubia or C. albifrontalis. An effect of host species on sex ratio was only observed at 27°C, at which a higher proportion of T. zealandicus females emerged from Ch. megacephala and Ch. rufifacies than from the other host species. The thermal requirements for development (developmental thresholds, thermal constant, optimum temperature) of T. zealandicus in each host species were estimated using linear and non-linear models. Upper and lower developmental thresholds ranged between 29.90°C and 31.73°C, and 9.73°C and 10.08°C, respectively. The optimum temperature for development was estimated at between 25.81°C and 27.05°C. Given the significant effect of host species on development time, the use of parasitoid,host-specific developmental data in forensic application is recommended. [source] Growth and developmental outcomes of three high-risk infant rhesus macaques (Macaca mulatta)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2007Amanda M. Dettmer Abstract Infants classified as "high risk" are born with a greater chance of developing medical complications at birth, and may have cognitive and other developmental complications later in life. Very few reports exist regarding the survival and outcome of such infants in primate colonies. Here we present early growth and developmental data on three high-risk infant rhesus macaques (one female and two males) that were born either with intrauterine growth restriction (IUGR; born below the 1st birth weight percentile for gestational age) or extremely prematurely (at gestational days 128 and 140; mean full-term gestation=164 days). We compared the outcome of these infants with that of healthy controls born at term and found no gross developmental delays in these infants with respect to growth, neonatal reflex and motor skill development, early cognitive development, or social behavior. Neurological and cognitive assessments were compared in terms of both postnatal and gestational age. The survival of these infants was dependent on a 24-hr staffed nursery and a fluid protocol that catered to each high-risk infant's individual needs. When such measures are implemented, infants such as these have a good chance of survival and can serve as excellent models for high-risk human babies and their subsequent development. Am. J. Primatol. 69:503,518, 2007. © 2007 Wiley-Liss, Inc. [source] Continuities and Discontinuities in Children and ScholarshipCHILD DEVELOPMENT, Issue 6 2008Lynn S. Liben This article introduces a collection of essays on continuity and discontinuity in cognitive development. In his lead essay, J. Kagan (2008) argues that limitations in past research (e.g., on number concepts, physical solidarity, and object permanence) render conclusions about continuity premature. Commentaries respectively (1) argue that longitudinal contexts are essential for interpreting developmental data, (2) illustrate the value of converging measures, (3) identify qualitative change via dynamical systems theory, (4) redirect the focus from states to process, and (5) review epistemological premises of alternative research traditions. Following an overview of the essays, this introductory article discusses how the search for developmental structures, continuity, and process differs between mechanistic-contextualist and organismic-contextualist metatheoretical frameworks, and closes by highlighting continuities in Kagan's scholarship over the past half century. [source] Modeling the Development of Children's Use of Optional Infinitives in Dutch and English Using MOSAICCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 2 2006Daniel Freudenthal Abstract In this study we use a computational model of language learning called model of syntax acquisition in children (MOSAIC) to investigate the extent to which the optional infinitive (OI) phenomenon in Dutch and English can be explained in terms of a resource-limited distributional analysis of Dutch and English child-directed speech. The results show that the same version of MOSAIC is able to simulate changes in the pattern of finiteness marking in 2 children learning Dutch and 2 children learning English as the average length of their utterances increases. These results suggest that it is possible to explain the key features of the OI phenomenon in both Dutch and English in terms of the interaction between an utterance-final bias in learning and the distributional characteristics of child-directed speech in the 2 languages. They also show how computational modeling techniques can be used to investigate the extent to which cross-linguistic similarities in the developmental data can be explained in terms of common processing constraints as opposed to innate knowledge of universal grammar. [source] | ||||||||||||||||||||||||||||