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Showing papers by "University of Windsor published in 2003"


Journal ArticleDOI
TL;DR: In this article, the contribution of amide-based receptors to the development of anion complexing agents is discussed, and the results of solution binding studies and sensing outputs are summarized.

549 citations


Journal ArticleDOI
TL;DR: Vitellogenesis, the process of yolk protein synthesis, transport, and uptake into the oocytes, and zonagenesis, the synthesis of eggshell zona radiata proteins, their transport and deposition by the maturing oocyte, are important aspects of oogenesis.
Abstract: The oocyte is the starting point for a new generation. Most of the machinery for DNA and protein synthesis needed for the developing embryo is made autonomously by the fertilized oocyte. However, in fish and in many other oviparous vertebrates, the major constituents of the egg, i.e. yolk and eggshell proteins, are synthesized in the liver and transported to the oocyte for uptake. Vitellogenesis, the process of yolk protein (vitellogenin) synthesis, transport, and uptake into the oocyte, and zonagenesis, the synthesis of eggshell zona radiata proteins, their transport and deposition by the maturing oocyte, are important aspects of oogenesis. The many molecular events involved in these processes require tight, coordinated regulation that is under strict endocrine control, with the female sex steroid hormone estradiol-17β in a central role. The ability of many synthetic chemical compounds to mimic this estrogen can lead to unscheduled hepatic synthesis of vitellogenin and zona radiata proteins, with potentially detrimental effects to the adult, the egg, the developing embryo and, hence, to the recruitment to the fish population. This has led to the development of specific and sensitive assays for these proteins in fish, and the application of vitellogenin and zona radiata proteins as informative biomarkers for endocrine disrupting effects of chemicals and effluents using fish as test organisms. The genes encoding these important reproductive proteins are conserved in the animal kingdom and are products of several hundred million years of evolution.

470 citations


Book
01 Jan 2003
TL;DR: In this paper, the authors introduce the concept of polarization and static dielectric constant, and introduce the notion of space charge in solids dielectrics, and present a theoretical analysis of these concepts.
Abstract: 1. Introductory Concepts 2. Polarization and Static Dielectric Constant 3. Dielectric Loss and Relaxation-I 4. Dielectric Loss and Relaxation-II 5. Experimental Data (Frequency Domain) 6. Absorption and Desorption Currents 7. Field Enhanced Conduction 8. Fundamental Aspects of Gaseous Breakdown-I 9. Fundamental Aspects of Electrical Breakdown-II 10. Thermally Stimulated Processes 11. Space Charge in Solids Dielectrics

430 citations


Journal ArticleDOI
TL;DR: Substantially more research is necessary to fully assess BFR fate, uptake and elimination kinetics, metabolic pathways, inter-species differences, the influence of congener structure, and the potential health risks to exposed organisms.

420 citations


Journal ArticleDOI
TL;DR: In this article, the authors show that an increase in the list price increases expected time-on-the-market (TOM) and that the effect of a higher list price is magnified for houses in a market segment having a low predicted variance of the list prices.
Abstract: When a house is placed on the market, the seller must choose the initial offer price. Setting the price too high or too low affects the marketability of the property. While there is near universal agreement that the seller faces a trade-off between selling at a higher price and selling in less time, there is less agreement about how to measure this trade-off. This paper offers a framework for analysis and shows that an increase in the list price increases expected time-on-the-market (TOM). Because house buyers must solve a type of signal extraction problem, the effect of a higher list price is magnified for houses in a market segment having a low predicted variance of the list price. This paper also shows that the list price of houses which are withdrawn before sale has a higher mean and variance, and that the possibility of withdrawal censors information about the time-on-the-market.

333 citations


Journal ArticleDOI
27 Feb 2003-Nature
TL;DR: In this article, the authors analyse hypotheses on speciation and dispersal for reef fish from the Indian and Pacific oceans and show how dispersal from a major center of origination can simultaneously account for both large-scale gradients in species richness and the structure of local communities.
Abstract: A central aim of ecology is to explain the heterogeneous distribution of biodiversity on earth. As expectations of diversity loss grow1,2,3,4,5, this understanding is also critical for effective management and conservation. Although explanations for biodiversity patterns are still a matter for intense debate5, they have often been considered to be scale-dependent6,7. At large geographical scales, biogeographers have suggested that variation in species richness results from factors such as area, temperature, environmental stability, and geological processes, among many others5,7,8,9,10,11,12,13,14. From the species pools generated by these large-scale processes, community ecologists have suggested that local-scale assembly of communities is achieved through processes such as competition, predation, recruitment, disturbances and immigration5,6,7,8,15,16. Here we analyse hypotheses on speciation and dispersal for reef fish from the Indian and Pacific oceans and show how dispersal from a major centre of origination can simultaneously account for both large-scale gradients in species richness and the structure of local communities.

324 citations


Journal ArticleDOI
14 Mar 2003-Science
TL;DR: In chinook salmon, hatchery rearing relaxes natural selection favoring large eggs, allowing fecundity selection to drive exceptionally rapid evolution of small eggs, and trends toward small eggs are also evident in natural populations heavily supplemented by hatcheries, but not in minimally supplemented populations.
Abstract: Captive breeding and release programs, widely used to supplement populations of declining species, minimize juvenile mortality to achieve rapid population growth However, raising animals in benign environments may promote traits that are adaptive in captivity but maladaptive in nature In chinook salmon, hatchery rearing relaxes natural selection favoring large eggs, allowing fecundity selection to drive exceptionally rapid evolution of small eggs Trends toward small eggs are also evident in natural populations heavily supplemented by hatcheries, but not in minimally supplemented populations Unintentional selection in captivity can lead to rapid changes in critical life-history traits that may reduce the success of supplementation or reintroduction programs

319 citations


Journal ArticleDOI
TL;DR: The results show neural correlates of access to specific word information, with robust differences in activation by words and word-like nonwords, and the absence of facilitatory lexical neighborhood effects on activation in these brain regions argues for an interpretation in terms of semantic access.
Abstract: People can discriminate real words from nonwords even when the latter are orthographically and phonologically word-like, presumably because words activate specific lexical and/or semantic information. We investigated the neural correlates of this identification process using event-related functional magnetic resonance imaging (fMRI). Participants performed a visual lexical decision task under conditions that encouraged specific word identification: Nonwords were matched to words on orthographic and phonologic characteristics, and accuracy was emphasized over speed. To identify neural responses associated with activation of nonsemantic lexical information, processing of words and nonwords with many lexical neighbors was contrasted with processing of items with no neighbors. The fMRI data showed robust differences in activation by words and word-like nonwords, with stronger word activation occurring in a distributed, left hemisphere network previously associated with semantic processing, and stronger nonword activation occurring in a posterior inferior frontal area previously associated with grapheme-to-phoneme mapping. Contrary to lexicon-based models of word recognition, there were no brain areas in which activation increased with neighborhood size. For words, activation in the left prefrontal, angular gyrus, and ventrolateral temporal areas was stronger for items without neighbors, probably because accurate responses to these items were more dependent on activation of semantic information. The results show neural correlates of access to specific word information. The absence of facilitatory lexical neighborhood effects on activation in these brain regions argues for an interpretation in terms of semantic access. Because subjects performed the same task throughout, the results are unlikely to be due to task-specific attentional, strategic, or expectancy effects.

315 citations


Journal ArticleDOI
TL;DR: In this article, the site of the reduction [Ru(NO)]3++e−→[Ru( NO)]2+ was assigned to the NO ligand based on molecular orbital (MO) analysis and on reduction product analysis.

275 citations


Journal ArticleDOI
TL;DR: In this paper, the authors developed a model grounded in the contingency theory applicable to Chinese state-owned enterprises (SOEs) and used data from a sample of 205 industrial SOEs.
Abstract: This study develops a model grounded in the contingency theory (i.e., context–structure–performance) applicable to Chinese state-owned enterprises (SOEs). Using data from a sample of 205 industrial SOEs, the study shows that SOE growth performance relative to the industry is positively predicted by formal control, inversely predicted by decentralization, and positively predicted by the interaction of the two. Customer product knowledge utilization, unrelated to growth performance relative to the industry, is positively predicted by formal control and the interaction of formal control with decentralization. Foreign induced industry competitiveness, technological turbulence, size, and production technology routineness are treated as context variables and modeled accordingly. Copyright © 2003 John Wiley & Sons, Ltd.

240 citations


Journal ArticleDOI
TL;DR: The experimental data of UV-SERS are in agreement with the preliminary theoretical calculation based on the electromagnetic enhancement mechanism and the enhancement factor is about 2 orders of magnitude for the Rh and Ru electrodes when they are excited at 325 nm.
Abstract: We report the first observation of surface-enhanced Raman scattering (SERS) excited with ultraviolet (UV) light from transition metal electrodes. Adsorbed pyridine and SCN- on rough rhodium (Rh) and ruthenium (Ru) electrodes, respectively, have been studied using 325 nm laser excitation. In contrast, the best enhancers in the visible and near infrared, silver and gold, do not produce UV-SERS. The experimental data of UV-SERS are in agreement with our preliminary theoretical calculation based on the electromagnetic enhancement mechanism. The enhancement factor is about 2 orders of magnitude for the Rh and Ru electrodes when they are excited at 325 nm.

Journal ArticleDOI
TL;DR: The increase in thalamic volume with increase in TBV was not seen in autism, suggesting underdeveloped connections between cortical and subcortical regions and indicating a need to examine this structure further.

Journal ArticleDOI
TL;DR: In this paper, a wavelet multiscaling approach is proposed to estimate the systematic risk (the beta of an asset) in a capital asset pricing model (CAPM), which decomposes a given time series on a scale-by-scale basis.
Abstract: In this paper we propose a new approach to estimating the systematic risk (the beta of an asset) in a capital asset pricing model (CAPM). The proposed method is based on a wavelet multiscaling approach that decomposes a given time series on a scale-by-scale basis. At each scale, the wavelet variance of the market return and the wavelet covariance between the market return and a portfolio are calculated to obtain an estimate of the portfolio's beta. The empirical results show that the relationship between the return of a portfolio and its beta becomes stronger as the wavelet scale increases. Therefore, the predictions of the CAPM model are more relevant in the medium long run as compared to short time horizons.

Journal ArticleDOI
TL;DR: In this article, a methodology to systematically determine the product and process complexity for any manufacturing environment was introduced - a rapid Manufacturing Complexity Assessment Tool (MCAT), which is based on three elements: total quantity of information, diversity of information and the information content which corresponds to the effort to produce a feature within a product.


Journal ArticleDOI
TL;DR: Using structural equation modeling (SEM) to clarify the relationship between subjective cognitive complaints and neuropsychological functioning in 160 adults with HIV infection indicated that although depressed mood and medical symptoms influenced cognitive complaints, cognitive complaints were independently associated with poorer neuroPsychological performance.
Abstract: The main objective of this study was to use structural equation modeling (SEM) to clarify the relationship between subjective cognitive complaints and neuropsychological functioning in 160 adults with HIV infection. Participants completed questionnaires assessing cognitive complaints, symptoms of depression, and HIV-related medical symptoms. Neuropsychological tests included measures of attention, verbal fluency, psychomotor skills, learning, memory, and executive skills. SEM was used to test models of the relationships among cognitive complaints, mood, and medical symptoms with neuropsychological functioning. The model indicated that although depressed mood (beta = 0.32, p < .01) and medical symptoms (beta = 0.31, p < .01) influenced cognitive complaints, cognitive complaints were independently associated with poorer neuropsychological performance (beta = 0.39, p < .01). Mood and medical symptoms were significantly correlated but were not significantly associated with neuropsychological skills.

Journal ArticleDOI
TL;DR: The results suggest that exposure to these pesticides can cause both stimulatory and suppressive immune changes in adult frogs and is doing so in wild populations.
Abstract: An injection study and a field study were used to investigate the hypothesis that environmental xenobiotics have the potential to alter the immune function of northern leopard frogs (Rana pipiens). Three assays, IgM-specific antibody response to keyhole limpet hemocyanin linked to dinitrophenyl (KLH-DNP), zymozan induced chemiluminescence (CL) of whole blood and the delayed-type hypersensitivity (DTH), were used to assay humoral, innate and cell-mediated immune endpoints. Sublethal doses of DDT (923 ng/g wet wt), malathion (990 ng/g wet wt), and dieldrin (50 ng/g wet wt) were used in the injection study. In all pesticide-injected groups, antibody response was dramatically suppressed, DTH reactions were enhanced, and respiratory burst was lower. When the order of administration of pesticides and antigens was reversed, no differences in immune function between the control and dosed groups were apparent, indicating that frogs exposed to pathogens prior to pesticide exposure can still respond. A field study found significant differences in immune function between frog populations in pesticide-exposed and pesticide-free locations. The antibody response and CL were suppressed and the DTH enhanced in frogs from Essex County (ON, Canada). Overall, the results suggest that exposure to these pesticides can cause both stimulatory and suppressive immune changes in adult frogs and is doing so in wild populations.

Journal ArticleDOI
TL;DR: In this article, a set of habitat-type definitions were devised and tested through a stakeholder-driven process to design a network of marine protected areas (MPAs), focusing on no-take marine reserves in the Seaflower Biosphere Reserve, San Andres Archipelago, Colombia.
Abstract: : Ecologists have paid increasing attention to the design of marine protected areas (MPAs), and their design advice consistently recommends representing all habitat types within MPAs or MPA networks as a means to provide protection to all parts of the natural ocean system. Recent developments of new habitat-mapping techniques make this advice more achievable, but the success of such an approach depends largely on our ability to define habitat types in a way that is ecologically relevant. We devised and tested the ecological relevance of a set of habitat-type definitions through our participation in a stakeholder-driven process to design a network of MPAs, focusing on no-take marine reserves in the Seaflower Biosphere Reserve, San Andres Archipelago, Colombia. A priori definitions of habitat types were ecologically relevant, in that our habitat-type definitions corresponded to identifiable and unique characteristics in the ecological communities found there. The identification of ecological pathways and connectivity among habitats also helped in designing ecologically relevant reserve boundaries. Our findings contributed to the overall design process, along with our summary of other general principles of marine reserve design. Extensive stakeholder input provided information concerning the resources and their patterns of use. These inputs also contributed to the reserve design process. We anticipate success for the Seaflower Biosphere Reserve at achieving conservation and social goals because its zoning process includes detailed yet flexible scientific advice and the participation of stakeholders at every step. Resumen: Los ecologos han puesto mayor atencion en el diseno de areas marinas protegidas (AMP), y sus sugerencias de diseno recomiendan consistentemente la representacion de todos los tipos de habitat en los AMP o en las redes de AMP como una forma de proporcionar proteccion a todas las partes del sistema oceanico natural. Desarrollos recientes de tecnicas de mapeo de habitat nuevas hacen que estas recomendaciones sean mas realizables, pero el exito de esta metodologia depende, en buena medida, de nuestra capacidad de definir tipos de habitat de manera ecologicamente relevante. Participando en un proceso conducido por grupos de interes para disenar una red de AMPs, concentrada en reservas marinas sin extraccion en la Reserva de la Biosfera Seaflower, Archipelago San Andres, Colombia, disenamos y probamos la relevancia ecologica de un conjunto de definiciones de tipos de habitat. Las definiciones a priori de tipos de habitat fueron ecologicamente relevantes porque nuestras definiciones de tipos de habitat correspondieron a caracteristicas unicas e identificables de las comunidades ecologicas encontradas ahi. La identificacion de trayectorias ecologicas y la conectividad entre habitats tambien ayudaron al diseno de limites de reserva ecologicamente relevantes. Nuestros hallazgos contribuyeron al proceso de diseno en su conjunto, junto con nuestra recopilacion de otros principios generales para el diseno de reservas marinas. La participacion de los grupos de interes proporciono informacion concerniente a los recursos y sus patrones de uso. Esta participacion tambien contribuyo al proceso de diseno de la reserva. Anticipamos el exito para la Reserva de la Biosfera Seaflower en el cumplimiento de sus metas sociales y de conservacion porque en su proceso de zonificacion se incluyen recomendaciones cientificas detalladas pero flexibles y la participacion de grupos de interes en cada etapa.

Journal ArticleDOI
TL;DR: A focus group interview conducted with a group of therapists in a large-scale, comprehensive family service agency in an Arab American community is described in this article, where participants represented various countries of origin, helping disciplines, and years of U.S. residence.
Abstract: In keeping with our pluralistic society, counselors have begun the task of attempting to understand issues of multicultural diversity. The purpose of this article is to describe a focus group interview conducted with a group of therapists in a large-scale, comprehensive family service agency in an Arab American community. Participants represented various countries of origin, helping disciplines, and years of U.S. residence. The interview format was semistructured, and the results confirmed what little was already known about the population and supplemented that body of knowledge with updated information. Implications for counseling and further research are discussed.


Journal ArticleDOI
TL;DR: It was concluded that automobile seat comfort is a unique science and ergonomics criteria, while serving as the basis for this science, cannot be applied blindly for they do not ensure comfortable automobile seats.

Journal ArticleDOI
TL;DR: In this article, a study of the coal-bearing, alluvial, deltaic, estuarine and shallow-marine sandstones of the Rio Bonito Formation, early Permian, Parana Basin (southern Brazil), reveals that the distribution of diagenetic alterations and of related reservoir quality evolution can be constrained within a sequence stratigraphic framework.
Abstract: Linking siliciclastic diagenesis to sequence stratigraphy allows a better understanding of the parameters controlling the spatial and temporal distribution of diagenetic alterations, and hence of reservoir quality. A study of the coal-bearing, alluvial, deltaic, estuarine and shallow-marine sandstones of the Rio Bonito Formation, early Permian, Parana Basin (southern Brazil), reveals that the distribution of diagenetic alterations and of related reservoir quality evolution can be constrained within a sequence stratigraphic framework. Calcite, dolomite, siderite, kaolinite and pyrite cementation is consistently linked to sequence and parasequence boundaries, transgressive and maximum flooding surfaces and is systematically distributed within lowstand, transgressive and highstand systems tracts. Diagenesis of coal layers at parasequence boundaries has promoted the formation of stratabound calcite (detectable in resistivity wire line logs), concretionary pyrite and kaolinite and of silicate grain dissolution in sandstones located above and below these boundaries, particularly in the transgressive systems tract. Meteoric water diagenesis caused grain dissolution and the formation of kaolinite in sandstones below sequence boundaries and in lowstand systems tract sandstones. Carbonate bioclasts and low sedimentation rates in lag deposits at parasequence boundaries, transgressive and maximum flooding surfaces favoured the formation of grain-rimming siderite. The results of this study are relevant to the exploration of coal-bed methane and other coal-bearing reservoirs, where it is crucial to unravel and predict the distribution and quality of reservoirs and compartments.

Journal ArticleDOI
TL;DR: In this paper, a review of recent developments of the creep-resistant magnesium alloys is presented, and the metallurgical principles for designing the creep resistant alloys are highlighted.
Abstract: Magnesium, as a lightweight construction material, has rapidly grown its applications in the automotive industry since the early 1990s. To maximize the weight reduction of vehicles by lightweight magnesium alloys in the coming years, the use of newly developed high-temperature magnesium alloys is expected to increase significantly, particularly in the powertrain applications where the creep resistance is always required. This article reviews recent developments of the creep-resistant magnesium alloys. Fundamental aspects of the creep deformation theory and mechanisms are described. The metallurgical principles for designing the creep-resistant alloys are highlighted. The creep behavior of magnesium and its conventional alloys is discussed based on some microstructure analyses. The mechanical properties, microstructure, and manufacturability of the newly developed creep-resistant magnesium alloys are also overviewed. The further research and development work is outlined in terms of developing magn...


Journal ArticleDOI
TL;DR: The series of 2-substituted diphenylphosphine pyridines 1−5 were synthesized and subsequently oxidized with silyl or aryl azides to give the series of pyridine−phosphinimine ligands.

Journal ArticleDOI
TL;DR: Impact of Cercopagis on the lower food web of Lake Ontario was explored through assessments of historical and seasonal abundance of the crustacean zooplankton, by conducting feeding experiments on the dominant prey of the invaders, and by estimating its food requirements.
Abstract: Summary 1. In North America, the invasive predatory cladoceran Cercopagis pengoi was first detected in Lake Ontario. We explored the impact of Cercopagis on the lower food web of Lake Ontario through assessments of historical and seasonal abundance of the crustacean zooplankton, by conducting feeding experiments on the dominant prey of the invader, and by estimating its food requirements. 2. Between 1999 and 2001, a decrease in the abundance of dominant members of the Lake Ontario zooplankton community (Daphnia retrocurva, Bosmina longirostris and Diacyclops thomasi) coincided with an increase in the abundance of Cercopagis. Daphnia retrocurva populations declined despite high fecundity in all 3 years, indicating that food limitation was not responsible. Chlorophyll a concentration generally increased, concomitant with a decline in the herbivorous cladoceran zooplankton in the lake. 3. Laboratory experiments demonstrated that Cercopagis fed on small-bodied species including D. retrocurva and B. longirostris. 4. Consumption demand of mid-summer populations of Cercopagis, estimated from a bioenergetic model of the confamilial Bythotrephes, was sufficient to reduce crustacean abundance, although the degree of expected suppression varied seasonally and interannually. 5. Predatory effects exerted by Cercopagis on the Lake Ontario zooplankton, while initially very pronounced, have decreased steadily as the species became established in the lake.

Journal ArticleDOI
TL;DR: This paper examined the role of gender, sports participation, and gender orientation in predicting individuals' domain-specific and global self-esteem, and found that participants' gender orientation and the type of sports in which they participate are moderating factors.
Abstract: The purpose of this study was to examine the role of gender, sports participation, and gender orientation in predicting individuals' domain-specific and global self-esteem. A sample of 100 Grade 11 students completed measures of self-perception, body image, gender orientation, and sports participation. The results showed that although boys reported greater satisfaction with weight and appearance, there were no gender differences in general self-worth. In addition, more feminine individuals who participated in competitive sports reported lower levels of perceived athletic competence and global self-worth, but reported higher self-esteem when they participated in more noncompetitive sports. Although sports participation does predict self-esteem, participants' gender orientation and the type of sports in which they participate are moderating factors.

Journal ArticleDOI
TL;DR: Results from this study indicate that vessels entering the Great Lakes with only residual ballast are a potential vector for the introduction of new nonindigenous species during multiport operations.
Abstract: Natural or anthropogenic movement of sediments may be an important vector for the dispersal of invertebrate resting stages between water bodies. Here we record the presence of invertebrate diapausing eggs in residual sediments from transoceanic vessels and explore whether these may pose an invasion risk. Viability of diapausing eggs was explored under light and dark conditions using sediment collected from eleven tanks on nine vessels operating on the Great Lakes. Seventeen cladoceran, copepod, and rotifer taxa were identified. Four of the species hatched have not yet been reported as established in the Great Lakes. Egg viability for individual species varied from 0% to 92%. Exposure to saline water may impact egg viability of some freshwater species. Generally, the proportion of eggs hatched in light and dark treatments did not differ significantly, indicating that light was not required to terminate diapause. As a result, eggs could potentially hatch in dark ballast tanks when immersed in freshwater loaded as ballast during operation on the Great Lakes. Viability of diapausing eggs differed among ballast tanks on a single vessel, indicating that tanks with independent ballast histories have different invasion risks. While additional work is needed to quantify risk, results from this study indicate that vessels entering the Great Lakes with only residual ballast are a potential vector for the introduction of new nonindigenous species during multiport operations.

Book ChapterDOI
TL;DR: Palaeontological, phylogeographic, and molecular evidence suggests that the natural, multiple colonizations of the Caspian basin via transient connections with the Black Sea and other basins played an important role in shaping the diversity of Caspia fauna.
Abstract: Incorporation of the fossil record and molecular markers into studies of biological invasions provides new historical perspectives on the incidence of natural and human-mediated invasions of nonindigenous species (NIS). Palaeontological, phylogeographic, and molecular evidence suggests that the natural, multiple colonizations of the Caspian basin via transient connections with the Black Sea and other basins played an important role in shaping the diversity of Caspian fauna. Geographically isolated, conspecific Ponto-Caspian lineages that currently inhabit fragmented habitats in the Ponto-Caspian region show limited genetic divergence, implying geologically recent episodes of gene flow between populations during the Pliocene to Pleistocene. Several molluscan lineages in the Caspian Sea may have descended from Lake Pannon stock before the Late Miocene isolation of the Caspian depression, about 5.8 million years ago. Anthropogenic activities during the 20th century were responsible for a 1800-fold increase in the rate of establishment of new aquatic species in the Caspian Sea compared to the preceding two million years of natural colonization. The observed success of NIS invasions during the 20th century was due primarily to humanmediated transport mechanisms, which were dominated by shipping activities (44%). Human-mediated species transfer has been strongly asymmetrical, toward the Volga Delta and Caspian Sea from or through Black and Azov Seas. Global and regional trade, particularly that mediated by commercial ships, provides dispersal opportunities for nonindigenous invertebrates, indicating that future invasions in the Caspian Sea are anticipated.

Journal ArticleDOI
TL;DR: Results suggest that the two PDD subtypes represent similar developmental trajectories, although the Asperger syndrome group maintains its advantage.
Abstract: This study prospectively compared the 2-year outcome of children diagnosed with autism or Asperger syndrome at age 6–8 years in terms of symptoms from the Autism Diagnostic Interview. Significant differences were seen in the three-domain summary scores of social interaction, communication, and repetitive activities, with the Asperger syndrome group demonstrating fewer and/or less severe symptoms at both times. There was a trend for the trajectories to come together over time on the socialization and communication domains, but not the repetitive activities domain. Differences were not attributable to IQ. Analysis of individual items indicated that the autism group improved over time on seven items and showed increased symptom severity on three items. On the other hand, the Asperger syndrome group improved on only two items and showed increased symptom severity on six items. Results suggest that the two PDD subtypes represent similar developmental trajectories, although the Asperger syndrome group maintains its advantage. Educational and clinical implications of the results are discussed.