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Terms modified by Highly Selected AbstractsWorkforce Segregation and the Gender Wage Gap: Is "Women's" Work Valued as Highly as "Men's"?,JOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 6 2008Christine Alksnis This study focuses on gender segregation and its implications for the salaries assigned to male- and female-typed jobs. We used a between-subjects design to examine whether participants would assign different pay to 3 types of jobs wherein the actual responsibilities and duties carried out by men and women were the same, but the job was situated in either a traditionally masculine or traditionally feminine domain. We found pay differentials between jobs defined as "male" and "female," which suggest that gender-based discrimination, arising from occupational stereotyping and the devaluation of the work typically done by women, influences salary allocation. The ways in which the results fit with contemporary theorizing about sexism and with the shifting standards model (Biernat, 1995, 2003) are discussed. [source] Rice Mitochondrial Genes Are Transcribed by Multiple Promoters That Are Highly DivergedJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 12 2006Qun-Yu Zhang Abstract Plant mitochondrial genes are often transcribed into complex sets of mRNA. To characterize the transcription initiation and promoter structure, the transcript termini of four mitochondrial genes, atp1, atp6, cob, rps7, in rice (Oryza sativa L.), were determined by using a modified circularized RNA reverse transcription-polymerase chain reaction method. The results revealed that three genes (atp1, atp6, rps7) were transcribed from multiple initiation sites, indicating the presence of multiple promoters. Two transcription termination sites were detected in three genes (atp6, cob, rps7), respectively. Analysis on the promoter architecture showed that the YRTA (Y=T or C, R=A or G) motifs that are widely present in the mitochondrial promoters of other monocotand dicot plant species were detected only in two of the 12 analyzed promoters. Our data suggest that the promoter sequences in the rice mitochondrial genome are highly diverged in comparison to those in other plants, and the YRTA motif is not an essential element for the promoter activity. (Managing editor: Li-Hui Zhao) [source] Synthesis of Nano-sized BaTiO3 Powders by the Rotary-Hydrothermal ProcessJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2009Takashi Kubo Nano-sized BaTiO3 powders with narrow size distribution and high tetragonality were attempted to be synthesized by the rotary-hydrothermal process in a water system as a novel technique, using a mixture of anatase-type TiO2 and Ba(OH)2 as starting material. The rotary-hydrothermal syntheses were performed under conditions with a rotary-speed of 20 revolutions per minute at 423,523 K for 3,96 h. Highly- and mono-dispersed BaTiO3 powders mainly composed of coarse-faceted particles with the tetragonal phase were successfully synthesized by controlling the conditions for rotary-hydrothermal treatments. TEM and TG results revealed that these coarse-faceted BaTiO3 particles contained very few structural defects such as hydroxyl content. Thus, the rotary-hydrothermal process was a useful method to synthesize very high-quality BaTiO3 particles, and the further control of various conditions of the rotary-hydrothermal treatment is expected to control the crystalline phase and microstructures of final BaTiO3 powders. [source] High Tunability of Highly (100)-Oriented Lead Zirconate Titanium Thin FilmsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2008Jiagang Wu Highly (100)-oriented Pb(Zr0.20Ti0.80)O3 (PZT) thin films for electrically tunable applications were prepared on Pt(111)/Ti/SiO2/Si(100) substrates by RF magnetron sputtering with a PbOx buffer layer. The dielectric properties of PZT films were investigated. These results indicated that the applied electric field and measured frequency strongly affected the films' tunability. The PZT films exhibited good dielectric tunability (69.3%) as measured at 1 kHz and 18 V. The related physics mechanism for enhanced tunability was also discussed. The enhanced tunability is attributed to the (100) orientation of PZT films and is a result of the biaxial tensile stress making the polar axis oriented in plane. [source] ChemInform Abstract: A Highly (E)-Stereoselective Approach to ,-Iodo Morita,Baylis,Hillman Esters: Synthesis of Secokotomolide A.CHEMINFORM, Issue 16 2008Sung Il Lee Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Highly 2,3-trans Stereoselective Allylations of 2,3-O-Isopropylidene-Protected Pyrrolidines: Circumventing the N-Acyliminium Ion Chemistry?CHEMINFORM, Issue 12 2001Pedro de Armas Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Shallow Bounding Volume Hierarchies for Fast SIMD Ray Tracing of Incoherent RaysCOMPUTER GRAPHICS FORUM, Issue 4 2008H. Dammertz Abstract Photorealistic image synthesis is a computationally demanding task that relies on ray tracing for the evaluation of integrals. Rendering time is dominated by tracing long paths that are very incoherent by construction. We therefore investigate the use of SIMD instructions to accelerate incoherent rays. SIMD is used in the hierarchy construction, the tree traversal and the leaf intersection. This is achieved by increasing the arity of acceleration structures, which also reduces memory requirements. We show that the resulting hierarchies can be built quickly and are smaller than acceleration structures known so far while at the same time outperforming them for incoherent rays. Our new acceleration structure speeds up ray tracing by a factor of 1.6 to 2.0 compared to a highly optimized bounding interval hierarchy implementation, and 1.3 to 1.6 compared to an efficient kd-tree. At the same time, the memory requirements are reduced by 10,50%. Additionally we show how a caching mechanism in conjunction with this memory efficient hierarchy can be used to speed up shadow rays in a global illumination algorithm without increasing the memory footprint. This optimization decreased the number of traversal steps up to 50%. [source] Pose Controlled Physically Based MotionCOMPUTER GRAPHICS FORUM, Issue 4 2006Raanan Fattal Abstract In this paper we describe a new method for generating and controlling physically-based motion of complex articulated characters. Our goal is to create motion from scratch, where the animator provides a small amount of input and gets in return a highly detailed and physically plausible motion. Our method relieves the animator from the burden of enforcing physical plausibility, but at the same time provides full control over the internal DOFs of the articulated character via a familiar interface. Control over the global DOFs is also provided by supporting kinematic constraints. Unconstrained portions of the motion are generated in real time, since the character is driven by joint torques generated by simple feedback controllers. Although kinematic constraints are satisfied using an iterative search (shooting), this process is typically inexpensive, since it only adjusts a few DOFs at a few time instances. The low expense of the optimization, combined with the ability to generate unconstrained motions in real time yields an efficient and practical tool, which is particularly attractive for high inertia motions with a relatively small number of kinematic constraints. [source] Automatic Creation of Object Hierarchies for Radiosity ClusteringCOMPUTER GRAPHICS FORUM, Issue 4 2000Gordon Müller Using object clusters for hierarchical radiosity greatly improves the efficiency and thus usability of radiosity computations. By eliminating the quadratic starting phase very large scenes containing about 100k polygons can be handled efficiently. Although the main algorithm extends rather easily to using object clusters, the creation of ,good' object hierarchies is a difficult task both in terms of construction time and in the way how surfaces or objects are grouped to clusters. The quality of an object hierarchy for clustering depends on its ability to accurately simulate the hierarchy of the energy flow in a given scene. Additionally it should support visibility computations by providing efficient ray acceleration techniques. In this paper we will present a new approach of building hierarchies of object clusters. Our hybrid structuring algorithm provides accuracy and speed by combining a highly optimized bounding volume hierarchy together with uniform spatial subdivisions for nodes with regular object densities. The algorithm works without user intervention and is well suited for a wide variety of scenes. First results of using these hierarchies in a radiosity clustering environment are very promising and will be presented here. The combination of very deep hierarchies (we use a binary tree) together with an efficient ray acceleration structure shifts the computational effort away from form factor and visibility calculation towards accurately propagating the energy through the hierarchy. We will show how an efficient single pass gathering can be used to minimize traversal costs. [source] Design and analysis of a scalable algorithm to monitor chord-based p2p systems at runtimeCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 6 2008Andreas Binzenhöfer Abstract Peer-to-peer (p2p) systems are a highly decentralized, fault tolerant, and cost-effective alternative to the classic client,server architecture. Yet companies hesitate to use p2p algorithms to build new applications. Due to the decentralized nature of such a p2p system the carrier does not know anything about the current size, performance, and stability of its application. In this paper, we present an entirely distributed and scalable algorithm to monitor a running p2p network. The snapshot of the system enables a telecommunication carrier to gather information about the current performance parameters of the running system as well as to react to discovered errors. Copyright © 2007 John Wiley & Sons, Ltd. [source] Agency Relations within the Family Business System: an exploratory approachCORPORATE GOVERNANCE, Issue 3 2003L.A.A. Van den Berghe Researchers use various definitions to describe the family firm. The characteristics of family firms that are stressed in each of these definitions are somehow related to family control. All characteristics together reflect a spectrum of family firm types along one core dimension: family involvement in the firm. However, it is more helpful to distinguish among family firms by using their precise type. Each particular family firm type is characterised by a set of agency relations within and between the family system, ownership system and the business system. This paper is a first attempt to apply the insights from agency theory on a highly simplified (reference) family firm situation where the father is full owner and the daughter manager of the family firm. Agency theory establishes the foundation for the optimal contract conditions between father and daughter. While real life is often characterised by bounded rationality and incomplete information, future research should help identify the "optimal contract" be-tween the family/shareholders and management in various family firm types under these circumstances. [source] Factors Associated with the Development of Board Sub,committeesCORPORATE GOVERNANCE, Issue 1 2002Elizabeth Carson This study examines the factors associated with the presence of board sub,committees, specifically audit, remuneration and nomination committees. Factors which are hypothesised in this study to affect sub,committee presence are Big 6 auditors, non,executive directors, non,executive chairmen, number of intercorporate relationships of the board and shareholder type. Company size, number of board members and leverage are employed as control variables as suggested by earlier research. An analysis of board sub,committees in the Australian corporate environment is relevant to other jurisdictions as there are no mandatory requirements on either board composition or board sub,committees. There is, however, a mandatory requirement to disclose corporate governance practices which allows for a study of this type to be reliably conducted. A sample of 361 Australian companies drawn from the largest 500 public companies is employed. Audit committee presence is found to be positively associated with Big 6 auditors and the number of intercorporate relationships of the directors of the board. Remuneration committees are also found to be associated with Big 6 auditors and intercorporate relationships and also higher levels of institutional investment. The presence of nomination committees is not associated with auditors, directors or investors, but is associated with board size and leverage. The study concludes that audit committees are a highly developed and mature governance mechanism, and that remuneration committees can be classed as a developing and maturing structure whilst nomination committees are relatively immature. [source] The Puzzle of Museum Educational Practice: A Comment on Rounds and FalkCURATOR THE MUSEUM JOURNAL, Issue 2 2006Daniel Spock The mandate that museums place education at the center of their public service role has had the effect of framing a new set of questions and,inevitably,problems. If museums have primary value to society as educational institutions, what kind of learning actually happens in them? Jay Rounds and John Falk, writing at the leading edge of this inquiry, explore curiosity, motivation and self-identity as paramount considerations for the special type of learning museums promote. Their analyses present interesting challenges for the museum practitioner, who may observe that people find the pursuit of curiosity pleasurable and value it more highly than knowledge acquisition. The practitioner may conclude that museums have a calling: They stand for the value of curiosity for its own sake, and for that reason will never wear out their welcome. [source] Single-cell image analysis to assess ABC-transporter,mediated efflux in highly purified hematopoietic progenitorsCYTOMETRY, Issue 4 2002H.G.P. Raaijmakers Abstract Background Normal and malignant hematopoietic stem cells are characterized by their capacity to actively extrude fluorescent dyes. The contribution of different ATP-binding cassette (ABC) transporters to this phenomenon is largely unknown due to the small stem cell numbers limiting the use of standard methods to assess functional efflux. Methods We used epifluorescence microscopy (EFM) in combination with single-cell image analysis to study ABC-transporter,mediated efflux in highly purified, viable, CD34+CD38- cells sorted on an adhesive biolayer. P-glycoprotein and multidrug-resistant protein (MRP)-mediated efflux were quantitated using fluorescent substrates (rhodamine-123 and calcein acetoxymethyl ester [calcein-AM]) and specific inhibitors (verapamil and probenecid, respectively). Results The feasibility, sensitivity, and reproducibility of rhodamine-123 efflux quantitation using single-cell EFM was shown in cell lines and compared with standard flow cytometric assessment. P-glycoprotein,mediated transport was higher in CD34+CD38- cells than in more differentiated progenitors (mean efflux index = 2.24 ± 0.35 and 1.14 ± 0.11, respectively; P = 0.01). P-glycoprotein,mediated transport was the main determinant of the rhodamine "dull" phenotype of these cells. In addition, significant MRP-mediated efflux was demonstrated in CD34+CD38- and CD38+ cells (mean efflux index = 1.42 ± 0.19 and 1.28 ± 0.18, respectively). Conclusion The described method is a valuable tool for assessing ABC-transporter,mediated efflux in highly purified single cells. Both P-glycoprotein and MRP-mediated efflux are present in human CD34+CD38- hematopoietic stem cells. Cytometry 49:135,142, 2002. © 2002 Wiley-Liss, Inc. [source] A CRITICAL LOOK AT PAP ADEQUECY: ARE OUR CRITERIA SATISFACTORY?CYTOPATHOLOGY, Issue 2006D.R. Bolick Liquid based Pap (LBP) specimen adequacy is a highly documented, yet poorly understood cornerstone of our GYN cytology practice. Each day, as cytology professionals, we make adequacy assessments and seldom wonder how the criteria we use were established. Are the criteria appropriate? Are they safe? What is the scientific data that support them? Were they clinically and statistically tested or refined to achieve optimal patient care? In this presentation, we will take a fresh look at what we know about Pap specimen adequacy and challenge some of the core assumptions of our daily practice. LBP tests have a consistent, well-defined surface area for screening, facilitating the quantitative estimates of slide cellularity. This provides an unprecedented opportunity to establish reproducible adequacy standards that can be subjected to scientific scrutiny and rigorous statistical analysis. Capitalizing on this opportunity, the TBS2001 took the landmark step to define specimen adequacy quantitatively, and set the threshold for a satisfactory LBP at greater than 5,000 well visualized squamous epithelial cells. To date, few published studies have attempted to evaluate the validity or receiver operator characteristics for this threshold, define an optimal threshold for clinical utility or assess risks of detection failure in ,satisfactory' but relatively hypocellular Pap specimens. Five years of cumulative adequacy and cellularity data of prospectively collected Pap samples from the author's laboratory will be presented, which will serve as a foundation for a discussion on ,Pap failure'. A relationship between cellularity and detection of HSIL will be presented. Risk levels for Pap failure will be presented for Pap samples of different cellularities. The effect of different cellularity criterion on unsatisfactory Pap rates and Pap failure rates will be demonstrated. Results from this data set raise serious questions as to the safety of current TBS2001 adequacy guidelines and suggest that the risk of Pap failure in specimens with 5,000 to 20 000 squamous cells on the slide is significantly higher than those assumed by the current criteria. TBS2001 designated all LBP to have the same adequacy criterion. Up to this point, it has been assumed that ThinPrep, SurePath, or any other LBP would be sufficiently similar that they should have the same adequacy criteria. Data for squamous cellularity and other performance characteristics of ThinPrep and SurePath from the author's laboratory will be compared. Intriguing data involving the recently approved MonoPrep Pap Test will be reviewed. MonoPrep clinical trial data show the unexpected finding of a strong correlation between abundance of endocervical component and the detection of high-grade lesions, provoking an inquiry of a potential new role for a quantitative assessment of the transition zone component. The current science of LBP adequacy criteria is underdeveloped and does not appear to be founded on statistically valid methods. This condition calls us forward as a body of practitioners and scientists to rigorously explore, clarify and define the fundamental nature of cytology adequacy. As we forge this emerging science, we will improve diagnostic performance, guide the development of future technologies, and better serve the patients who give us their trust. Reference:, Birdsong GG: Pap smear adequacy: Is our understanding satisfactory? Diagn Cytopathol. 2001 Feb; 24(2): 79,81. [source] Psychological resilience and neurocognitive performance in a traumatized community sample,DEPRESSION AND ANXIETY, Issue 8 2010Aliza P. Wingo M.D. Abstract Background: Whether psychological resilience correlates with neurocognitive performance is largely unknown. Therefore, we assessed association between neurocognitive performance and resilience in individuals with a history of childhood abuse or trauma exposure. Methods: In this cross-sectional study of 226 highly traumatized civilians, we assessed neurocognitive performance, history of childhood abuse and other trauma exposure, and current depressive and PTSD symptoms. Resilience was defined as having ,1 trauma and no current depressive or PTSD symptoms; non-resilience as having ,1 trauma and current moderate/severe depressive or PTSD symptoms. Results: The non-resilient group had a higher percentage of unemployment (P=.006) and previous suicide attempts (P<.0001) than the resilient group. Both groups had comparable education and performance on verbal reasoning, nonverbal reasoning, and verbal memory. However, the resilient group performed better on nonverbal memory (P=.016) with an effect size of .35. Additionally, more severe childhood abuse or other trauma exposure was significantly associated with non-resilience. Better nonverbal memory was significantly associated with resilience even after adjusting for severity of childhood abuse, other trauma exposure, sex, and race using multiple logistic regression (adjusted OR=1.2; P=.017). Conclusions: We examined resilience as absence of psychopathology despite trauma exposure in a highly traumatized, low socioeconomic, urban population. Resilience was significantly associated with better nonverbal memory, a measure of ability to code, store, and visually recognize concrete and abstract pictorial stimuli. Nonverbal memory may be a proxy for emotional learning, which is often dysregulated in stress-related psychopathology, and may contribute to our understanding of resilience. Depression and Anxiety, 2010. © 2010 Wiley-Liss, Inc. [source] Drought, Domestic Budgeting and Wealth Distribution in Sahelian HouseholdsDEVELOPMENT AND CHANGE, Issue 5 2000Matthew Turner Over the past twenty-five years, Sahelian households have experienced recurrent harvest failure and greater reliance on remittances from migratory wage labour. Household subsistence has become less dependent on household grain stores and more on the liquidation of individual wealth stores. This study investigates how these broader changes have affected struggles between household members over obligations to support the household in the Zarmaganda region of western Niger. As the land-derived leverage of male patriarchs has declined and household dependence on individual wealth stores has increased, domestic budgeting has become more contested. Household heads make case-by-case moral claims on other household members during times of grain shortage. Women and subordinate males invoke Islamic law, which accords primary provisioning responsibility to the household head, to protect their individual wealth in times of grain deficit. This article investigates the nature of these budgetary struggles, showing how individuals' decisions to contribute individual wealth to support the household are best understood as highly situated, affected not only by the specific material conditions of the household but also the interplay of the moral, structural, and individualistic imperatives that derive from one's position within the household. Using reconstructed livestock wealth histories for the members of fifty-four households in western Niger, this study investigates the material consequences of these struggles. Male heads of corporate households, the historic managers of the household's land and agricultural labour, have lost wealth relative to their wives and married male subordinates since the drought of 1984. [source] Gene expression in the efferent ducts, epididymis, and vas deferens during embryonic development of the mouseDEVELOPMENTAL DYNAMICS, Issue 9 2010Elizabeth M. Snyder Abstract The tissues of the male reproductive tract are characterized by distinct morphologies, from highly coiled to un-coiled. Global gene expression profiles of efferent ducts, epididymis, and vas deferens were generated from embryonic day 14.5 to postnatal day 1 as tissue-specific morphologies emerge. Expression of homeobox genes, potential mediators of tissue-specific morphological development, was assessed. Twenty homeobox genes were identified as either tissue-enriched, developmentally regulated, or both. Additionally, ontology analysis demonstrated cell adhesion to be highly regulated along the length of the reproductive tract. Regulators of cell adhesion with variable expression between the three tissues were identified including Alcam, various cadherins, and multiple integrins. Immunofluorescence localization of the cell adhesion regulators POSTN and CDH2 demonstrated cell adhesion in the epithelium and mesenchyme of the epididymis may change throughout development. These results suggest cell adhesion may be modulated in a tissue-specific manner, playing an important role in establishing each tissue's final morphology. Developmental Dynamics 239:2479,2491, 2010. © 2010 Wiley-Liss, Inc. [source] RNA expression microarray analysis in mouse prospermatogonia: Identification of candidate epigenetic modifiers,DEVELOPMENTAL DYNAMICS, Issue 4 2008Christophe Lefèvre Abstract The mammalian totipotent and pluripotent lineage exhibits genome-wide dynamics with respect to DNA methylation content. The first phase of global DNA demethylation and de novo remethylation occurs during preimplantation development and gastrulation, respectively, while the second phase occurs in primordial germ cells and primary oocytes/prospermatogonia, respectively. These dynamics are indicative of a comprehensive epigenetic resetting or reprogramming of the genome in preparation for major differentiation events. To gain further insight into the mechanisms driving DNA methylation dynamics and other types of epigenetic modification, we performed an RNA expression microarray analysis of fetal prospermatogonia at the stage when they are undergoing rapid de novo DNA remethylation. We have identified a number of highly or specifically expressed genes that could be important for determining epigenetic change in prospermatogonia. These data provide a useful resource in the discovery of molecular pathways involved in epigenetic reprogramming in the mammalian germ line. Developmental Dynamics 237:1082,1089, 2008. © 2008 Wiley-Liss, Inc. [source] Expression profiles of the duplicated matrix metalloproteinase-9 genes suggest their different roles in apoptosis of larval intestinal epithelial cells during Xenopus laevis metamorphosisDEVELOPMENTAL DYNAMICS, Issue 8 2007Takashi Hasebe Abstract Matrix metalloproteinases (MMPs) play a pivotal role in development and/or pathogenesis through degrading extracellular matrix (ECM) components. We have previously shown that Xenopus MMP-9 gene is duplicated. To assess possible roles of MMP-9 and MMP-9TH in X. laevis intestinal remodeling, we here analyzed their expression profiles by in situ hybridization and show that their expression is transiently up-regulated during thyroid hormone-dependent metamorphosis. Of interest, MMP-9TH mRNA is strictly localized in the connective tissue and most highly expressed just beneath the larval epithelium that begins to undergo apoptosis. On the other hand, cells expressing MMP-9 mRNA become first detectable in the connective tissue and then, after the start of epithelial apoptosis, also in the larval epithelium. These results strongly suggest that MMP-9TH is responsible in the larval epithelial apoptosis through degrading ECM components in the basal lamina, whereas MMP-9 is involved in the removal of dying epithelial cells during amphibian intestinal remodeling. Developmental Dynamics 236:2338,2345, 2007. © 2007 Wiley-Liss, Inc. [source] A MAGE/NDN-like gene in zebrafishDEVELOPMENTAL DYNAMICS, Issue 3 2003Jocelyn M. Bischof Abstract The human necdin/MAGE gene family has over 50 members, but most of the proteins encoded by these genes are of unknown function. We have now identified a single locus in Danio rerio that encodes a putative protein with significant coding sequence similarity to the mammalian NDN/MAGE genes. Analysis of the complete Fugu ribripes genome sequence also suggests that there is only a single MAGE-like gene in teleost fish. mage is expressed in the larval and adult brain, specifically the retina, the medial region of the telencephalon, periventricular gray zone of the optic tectum, and most highly in the cerebellar corpus. The discovery of a zebrafish NDN/MAGE gene expressed the developing brain facilitates studies of the MAGE homology domain in vertebrate development. Developmental Dynamics, 2003. © 2003 Wiley-Liss, Inc. [source] Socio-economic achievements of individuals born very preterm at the age of 27 to 29 years: a nationwide cohort studyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2009RENÉ MATHIASEN MD Aim, To describe the socio economic achievement of individuals born very preterm (VPT) at the age of 27 to 29 years. Method, Demographic and social data were extracted from national registers for all individuals born between 1974 and 1976 in Denmark (n=208 656). Of these, 203 283 individuals were alive in 2006. We compared VPT individuals (gestational age <33wks, n=1422; 51.8% males, n=736) with individuals born at term (>36wks, n=192 223; 51.1% males, n=98 240), of whom 4.08% (n=58) of the VPT and 0.19% (n=373) of the term individuals had a diagnosis of cerebral palsy (CP). Results, Overall results in the two groups were similar, but significant differences appeared. The VPT group had a lower educational level than the term group: 23.9% versus 16.3% had a basic education (corresponding to attendance at basic school for 9y or less; odds ratio [OR] =1.61, 95% confidence interval [CI] 1.42,1.82). Similarly, 31.9% versus 37.6% had a tertiary education (corresponding to different levels of professional education; OR=0.77, CI 0.69,0.86). Net income was 11% lower in the VPT group and 10.8% versus 5.3% were receiving welfare support (OR=2.14, CI 1.81,2.55). In the VPT group 59% versus 52% did not have children (p<0.001) and there were more individuals living alone without children (28.8% vs 21.8%; OR=1.45, CI 1.29,1.63). Interpretation, VPT birth in the 1970s in Denmark is associated with a highly statistically significant educational and social disadvantage persisting into young adulthood. CP increased the relative risk of social disadvantage in VPT individuals. However, the majority of the survivors are well integrated in society. [source] Adult neurogenesis in the crayfish brain: Proliferation, migration, and possible origin of precursor cellsDEVELOPMENTAL NEUROBIOLOGY, Issue 7 2009Yi Zhang Abstract The birth of new neurons and their incorporation into functional circuits in the adult brain is a characteristic of many vertebrate and invertebrate organisms, including decapod crustaceans. Precursor cells maintaining life-long proliferation in the brains of crayfish (Procambarus clarkii, Cherax destructor) and clawed lobsters (Homarus americanus) reside within a specialized niche on the ventral surface of the brain; their daughters migrate to two proliferation zones along a stream formed by processes of the niche precursors. Here they divide again, finally producing interneurons in the olfactory pathway. The present studies in P. clarkii explore (1) differential proliferative activity among the niche precursor cells with growth and aging, (2) morphological characteristics of cells in the niche and migratory streams, and (3) aspects of the cell cycle in this lineage. Morphologically symmetrical divisions of neuronal precursor cells were observed in the niche near where the migratory streams emerge, as well as in the streams and proliferation zones. The nuclei of migrating cells elongate and undergo shape changes consistent with nucleokinetic movement. LIS1, a highly conserved dynein-binding protein, is expressed in cells in the migratory stream and neurogenic niche, implicating this protein in the translocation of crustacean brain neuronal precursor cells. Symmetrical divisions of the niche precursors and migration of both daughters raised the question of how the niche precursor pool is replenished. We present here preliminary evidence for an association between vascular cells and the niche precursors, which may relate to the life-long growth and maintenance of the crustacean neurogenic niche. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009 [source] Social influences on formula intake via suckling in 7 to 14-week-old-infantsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2007Julie C. Lumeng Abstract To investigate social influences on human suckling behavior, 25 healthy, full term, 7 to 14-week-old infants were each bottle-fed their own formula twice by their mother and once in each of four experimental conditions: (a) held, provided social interaction; (b) held, without interaction; (c) not held, provided interaction; (d) not held, without interaction. Volume intake (VI), Total Sucks, infant gaze direction, and time elapsed since the last feeding were determined. There were three major findings: (1) social interaction increased VI; (2) VI was linearly related to the time since the last feeding in held infants; (3) Total Sucks and VI were both highly correlated with privation length when infants did not look at the feeder and when fed by the mother. Thus, social influences exert strong immediate impacts on suckling. Accordingly, suckling functions to obtain both nutrition from and social information about the feeder. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 351,361, 2007. [source] Social withdrawal behaviors in nonhuman primates and changes in neuroendocrine and monoamine concentrations during a separation paradigm,DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2005Kristine Erickson Abstract This study investigated relationships between withdrawal behaviors in rhesus macaques and changes in monoamine metabolite and endocrine concentrations during repeated psychosocial stress. Rhesus monkeys (N,=,71) experienced maternal separation in which four separations took place during four consecutive weeks. Behavioral observations were made, as well as plasma concentrations of cortisol and cerebrospinal fluid concentrations of the serotonin, dopamine, and norepinephrine metabolites were obtained. Animals were assigned to high, moderate, and low withdrawal groups, defined using baseline durations of withdrawal behaviors. Highly withdrawn animals showed less reduction than nonwithdrawn animals in serotonin metabolite concentrations over repeated separations. Highly withdrawn macaques also failed to significantly reduce cortisol concentrations across separation weeks. More adaptation in central serotonin functioning and cortisol concentrations was seen in nonwithdrawn primates than in highly withdrawn primates; these findings have implications for increased risk of developing anxiety disorders in highly inhibited children. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46:331,339, 2005. [source] Vegetation and topographic controls on sediment deposition and storage on gully beds in a degraded mountain areaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2009Armando Molina Abstract Active gully systems developed on highly weathered or loose parent material are an important source of runoff and sediment production in degraded areas. However, a decrease of land pressure may lead to a return of a partial vegetation cover, whereby gully beds are preferred recolonization spots. Although the current knowledge on the role of vegetation on reducing sediment production on slopes is well developed, few studies exist on the significance of restoring sediment transport pathways on the total sediment budget of degraded mountainous catchments. This study in the Ecuadorian Andes evaluates the potential of vegetation to stabilize active gully systems by trapping and retaining eroded sediment in the gully bed, and analyses the significance of vegetation restoration in the gully bed in reducing sediment export from degraded catchments. Field measurements on 138 gully segments located in 13 ephemeral steep gullies with different ground vegetation cover indicate that gully bed vegetation is the most important factor in promoting short-term (1,15 years) sediment deposition and gully stabilization. In well-vegetated gully systems ( , 30% of ground vegetation cover), 0.035 m3 m,1 of sediment is deposited yearly in the gully bed. Almost 50 per cent of the observed variance in sediment deposition volumes can be explained by the mean ground vegetation cover of the gully bed. The presence of vegetation in gully beds gives rise to the formation of vegetated buffer zones, which enhance short-term sediment trapping even in active gully systems in mountainous environments. Vegetation buffer zones are shown to modify the connectivity of sediment fluxes, as they reduce the transport efficiency of gully systems. First calculations on data on sediment deposition patterns in our study area show that gully bed deposition in response to gully bed revegetation can represent more than 25 per cent of the volume of sediment generated within the catchment. Our findings indicate that relatively small changes in landscape connectivity have the potential to create strong (positive) feedback loops between erosion and vegetation dynamics. Copyright © 2009 John Wiley & Sons, Ltd. [source] Sediment transport in a highly regulated fluvial system during two consecutive floods (lower Ebro River, NE Iberian Peninsula)EARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2005Damia Vericat Abstract The transfer of sediment through a highly regulated large fluvial system (lower Ebro River) was analysed during two consecutive floods by means of sediment sampling. Suspended sediment and bedload transport were measured upstream and downstream of large reservoirs. The dams substantially altered flood timing, particularly the peaks, which were advanced downstream from the dams for flood control purposes. The suspended sediment yield upstream from the dams was 1 700 000 tonnes, which represented nearly 99 per cent of the total solid yield. The mean concentrations were close to 0·5 g l,1. The sediment yield downstream from the dams was an order of magnitude lower (173 000 tonnes), showing a mean concentration of 0·05 g l,1. The dams captured up to 95 per cent of the fine sediment carried in suspension in the river channel, preventing it from reaching the lowermost reaches of the river and the delta plain. Total bedload transport upstream from the dams was estimated to be about 25 000 tonnes, only 1·5 per cent of the total load. The median bedload rate was 100 gms,1. Below the dams, the river carried 178 000 tonnes, around 51 per cent of the total load, at a mean rate of 250 g ms,1. The results of sediment transport upstream and downstream from the large dams illustrate the magnitude of the sediment deficit in the lower Ebro River. The river mobilized a total of 350 000 tonnes in the downstream reaches, which were not replaced by sediment from upstream. Therefore, sediment was necessarily entrained from the riverbed and channel banks, causing a mean incision of 33 mm over the 27 km long study reach, altogether a significant step towards the long-term degradation of the lower Ebro River. Copyright © 2005 John Wiley & Sons, Ltd. [source] Assessing the influence of environmental heterogeneity on bird spacing patterns: a case study with two raptorsECOGRAPHY, Issue 2 2006Thomas Cornulier Testing for aggregation or regularity in point patterns is difficult in the presence of spatial variation in abundance due to environmental heterogeneity. Using a recently developed method generalizing Ripley's K function for non homogeneous point patterns, we test the aggregation of the nests in two species of birds (little owl and Montagu's harrier) exhibiting heterogeneous distributions in response to landscape structure. We compare the results obtained under different null models accounting for environmental heterogeneity at large and/or small spatial scales. Whereas both species were initially found to form clusters at some scale, taking spatial heterogeneity into account revealed that 1) territorial little owls showed no clustering of territories when habitat availability was considered; 2) semi-colonial harriers still formed significant clusters, but part of the aggregation in this species could be explained by landscape structure alone. Our results highlight that it is feasible and highly recommended to account for non-stationarity when testing for aggregation. Further, provided that sufficient knowledge of the study system is available, this approach helps to identify behavioural and environmental components of spatial variation in abundance. Additionally, we demonstrate that accounting for large or small-scale heterogeneity affects the perception of spacing behaviours differently, so that both need to be considered. [source] Assessing the habitat quality of oil mallees and other planted farmland vegetation with reference to natural woodlandECOLOGICAL MANAGEMENT & RESTORATION, Issue 3 2009F. Patrick Smith Summary, Much of the tree and shrub planting that has been conducted on farms in Western Australia over the past three decades has not been done with the specific intention of creating habitat or conserving biodiversity, particularly commercially oriented monocultures like oil mallee plantings. However, such plantings may nonetheless provide some habitat resources for native plants and animals. This study assessed the habitat quality of farm plantings (most of which were not planted with the primary intention of biodiversity conservation) at 72 sites across a study region in the central wheatbelt of Western Australia. Widely accepted habitat metrics were used to compare the habitat resources provided by planted farmland vegetation with those provided by remnant woodland on the same farms. The impact of adjacency of plantings to woodland and, in the case of oil mallees, the planting configuration on predicted habitat quality is assessed. Condition Benchmarks for five local native vegetation communities are proposed. Farmland plantings achieved an average Vegetation Condition Score (VCS) of 46 out of a possible 100, while remnant woodland on the same farms scored an average 72. The average scores for farm plantings ranged from 38,59 depending on which of five natural vegetation communities was used as its benchmark, but farm plantings always scored significantly less than remnant woodland (P < 0.001). Mixed species plantings on average were rated more highly than oil mallees (e.g. scores of 42 and 36 respectively using the Wandoo benchmark) and adjacency to remnant woodland improved the score for mixed plantings, but not for oil mallees. Configuration of oil mallees as blocks or belts (i.e. as an alley farming system) had no impact on the VCS. Planted farmland vegetation fell short of remnant woodland in both floristic richness (51 planted native species in total compared with a total of more than 166 naturally occurring plant species in woodland) and structural diversity (with height, multiple vegetation strata, tree hollows and woody debris all absent in the relatively young 7,15-year-old farm plantings). Nonetheless farmland plantings do have measurable habitat values and recruitment and apparent recolonization of plantings with native plant species was observed. Habitat values might be expected to increase as the plantings age. The VCS approach, including the application of locally relevant Benchmarks is considered to be valuable for assessing potential habitat quality in farmland vegetation, particularly as a tool for engaging landholders and natural resource management practitioners. [source] Influence of seasonal, diel, lunar, and other environmental factors on upstream fish passage in the Igarapava Fish Ladder, BrazilECOLOGY OF FRESHWATER FISH, Issue 3 2009P. M. Bizzotto Abstract,,, Upstream fish passage was evaluated during 12 months in the vertical-slot Igarapava Fish Ladder constructed around Igarapava Dam, in the heavily dammed Grande River, Southeast Brazil. A video monitoring system was used to observe 61,621 fish that passed the ladder, of which 93.5% were identified to 15 taxa. Among the migratory species, the most abundant were Pimelodus maculatus (33.6% of all fish), Leporinus octofasciatus (31.4%), Leporinus friderici (4.5%), and Prochilodus lineatus (3.1%). Seven taxa were classified as nonmigratory, and of these taxa, the small Bryconamericus stramineus was the most abundant (12.7%) of all fishes. Passage of the ,nonmigratory' taxa upstream in the ladder shows they are migratory in this system and have a strong behavioural drive to move to upstream habitat. Passage of most taxa had a strong seasonal pattern. While some species passed primarily during the day, others showed a distinct nocturnal pattern. Lunar phase and water temperature also strongly affected passage of some taxa. Rainfall and dam discharge had a small or null influence on most taxa; perhaps due to the fairly small catchment area of the reservoir and the highly regulated discharge at Igarapava Dam. [source] | ||||||||||||||||||||||||||||||||||||||||