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Selected AbstractsComplementary expression and heterophilic interactions between igLON family members neurotrimin and LAMPDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2002Orlando D. Gil Abstract Neurotrimin (Ntm) and the limbic system-associated membrane protein (LAMP) are members of the IgLON (LAMP, OBCAM, Ntm) family of glycorylphosphatidylinositol anchored neural cell adhesion molecules. We previously reported that LAMP and Ntm promote adhesion and neurite outgrowth via a homophilic mechanism, suggesting that these proteins promote the formation of specific neuronal circuits by homophilic interactions. In this report, we have further characterized the expression and binding specificity of Ntm. Using a newly generated monoclonal antibody to Ntm, we demonstrated that this protein is largely expressed in a complementary pattern to that of LAMP in the nervous system, with co-expression at a few sites. Ntm is expressed at high levels in sensory-motor cortex and, of particular note, is transiently expressed in neurons of cortical barrel fields and corresponding thalamic "barreloids." Binding of a recombinant, soluble form of Ntm to CHO cells expressing either Ntm or LAMP demonstrates that Ntm and LAMP interact both homophilically and heterophilically. In contrast to conventional growth-promoting activity of Ig superfamily members, LAMP strongly inhibits the outgrowth of Ntm-expressing dorsal root ganglion (DRG) neurons in a heterophilic manner. These anatomical and functional data support the concept that homophilic and heterophilic interactions between IgLON family members are likely to play a role in the specification of neuronal projections via growth promoting and inhibiting effects, respectively. © 2002 Wiley Periodicals, Inc. J Neurobiol 51: 190,204, 2002 [source] Change in mean temperature as a predictor of extreme temperature change in the Asia,Pacific regionINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 10 2005G. M. Griffiths Abstract Trends (1961,2003) in daily maximum and minimum temperatures, extremes and variance were found to be spatially coherent across the Asia,Pacific region. The majority of stations exhibited significant trends: increases in mean maximum and mean minimum temperature, decreases in cold nights and cool days, and increases in warm nights. No station showed a significant increase in cold days or cold nights, but a few sites showed significant decreases in hot days and warm nights. Significant decreases were observed in both maximum and minimum temperature standard deviation in China, Korea and some stations in Japan (probably reflecting urbanization effects), but also for some Thailand and coastal Australian sites. The South Pacific convergence zone (SPCZ) region between Fiji and the Solomon Islands showed a significant increase in maximum temperature variability. Correlations between mean temperature and the frequency of extreme temperatures were strongest in the tropical Pacific Ocean from French Polynesia to Papua New Guinea, Malaysia, the Philippines, Thailand and southern Japan. Correlations were weaker at continental or higher latitude locations, which may partly reflect urbanization. For non-urban stations, the dominant distribution change for both maximum and minimum temperature involved a change in the mean, impacting on one or both extremes, with no change in standard deviation. This occurred from French Polynesia to Papua New Guinea (except for maximum temperature changes near the SPCZ), in Malaysia, the Philippines, and several outlying Japanese islands. For urbanized stations the dominant change was a change in the mean and variance, impacting on one or both extremes. This result was particularly evident for minimum temperature. The results presented here, for non-urban tropical and maritime locations in the Asia,Pacific region, support the hypothesis that changes in mean temperature may be used to predict changes in extreme temperatures. At urbanized or higher latitude locations, changes in variance should be incorporated. Copyright © 2005 Royal Meteorological Society. [source] Relationships between local population persistence, local abundance and regional occupancy of species: distribution patterns of diatoms in boreal streamsJOURNAL OF BIOGEOGRAPHY, Issue 11 2005Janne Soininen Abstract Aims, We have two aims: (1) to examine the relationship between local population persistence, local abundance and regional occupancy of stream diatoms and (2) to characterize the form of the species,occupancy frequency distribution of stream diatoms. Location, Boreal streams in Finland. There were three spatial extents: (1) across ecoregions in Finland, (2) within ecoregions in Finland, and (3) within a single drainage system in southern Finland. Methods, Diatoms were sampled from stones (epilithon), sediment (epipelon) and aquatic plants (epiphyton) in streams using standardized sampling methods. To assess population persistence, diatom sampling was conducted monthly at four stream sites from June to October. The relationships between local population persistence, local abundance and regional occupancy were examined using correlation analyses. Results, There was a significant positive relationship between local persistence and abundance of diatoms in epilithon, epipelon and epiphyton. Furthermore, local abundance and regional occupancy showed a significant positive relationship at multiple spatial extents; that is, across ecoregions, within ecoregions and within a drainage system. The relationships between occupancy and abundance did not differ appreciably among impacted and near pristine-reference sites. The occupancy,frequency distribution was characterized by a large number of satellite species which occurred at only a few sites, whereas core species that occurred at most sites were virtually absent. Main conclusions, The positive relationship between local population persistence and abundance suggested that a high local abundance may prevent local extinction or that high persistence is facilitated by a high local cell density. High local persistence and local abundance may also positively affect the degree of regional occupancy in stream diatoms. The results further showed that anthropogenic effects were probably too weak to bias the relationship between occupancy and abundance, or that the effects have already modified the distribution patterns of stream diatoms. The small number of core species in the species,occupancy frequency distribution suggested that the regional distribution patterns of stream diatoms, or perhaps unicellular microbial organisms in general, may not be fundamentally different from those described previously for multicellular organisms, mainly in terrestrial environments, although average global range sizes may differ sharply between these two broad groups of organisms. [source] Periodontal wound healing/regeneration following the application of rhGDF-5 in a , -TCP/PLGA carrier in critical-size supra-alveolar periodontal defects in dogsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2010David H. Kwon Kwon DH, Bisch FC, Herold RW, Pompe C, Bastone P, Rodriguez NA, Susin C, Wikesjö UM. Periodontal wound healing/regeneration following application of rhGDF-5 in a , -TCP/PLGA carrier in critical-size supra-alveolar periodontal defects in dogs. J Clin Periodontol 2010; 37: 667,674. doi: 10.1111/j.1600-051X.2010.01569.x. Abstract Aim: The objective of this study was to evaluate the effect of a novel recombinant human GDF-5 (rhGDF-5) construct intended for onlay and inlay indications on periodontal wound healing/regeneration. Methods: Contralateral, surgically created, critical-size, 6-mm, supra-alveolar periodontal defects in five adult Hound Labrador mongrel dogs received rhGDF-5 coated onto , -tricalcium phosphate (, -TCP) particles and immersed in a bioresorbable poly(lactic- co -glycolic acid) (PLGA) composite or the , -TCP/PLGA carrier alone (control). The rhGDF-5 and control constructs were moulded around the teeth and allowed to set. The gingival flaps were then advanced; flap margins were adapted 3,4 mm coronal to the teeth and sutured. The animals were euthanized at 8 weeks post-surgery when block biopsies were collected for histometric analysis. Results: Healing was generally uneventful. A few sites exhibited minor exposures. Three control sites and one rhGDF-5 site (in separate animals) experienced more extensive wound dehiscencies. The rhGDF-5 and control constructs were easy to apply and exhibited adequate structural integrity to support the mucoperiosteal flaps in this challenging onlay model. Limited residual , -TCP particles were observed at 8 weeks for both rhGDF-5/, -TCP/PLGA and , -TCP/PLGA control sites. The rhGDF-5/, -TCP/PLGA sites showed significantly greater cementum (2.34 ± 0.44 versus 1.13 ± 0.25 mm, p=0.02) and bone (2.92 ± 0.66 versus 1.21 ± 0.30 mm, p=0.02) formation compared with the carrier control. Limited ankylosis was observed in four of five rhGDF-5/, -TCP/PLGA sites but not in control sites. Conclusions: Within the limitations of this study, the results suggest that rhGDF-5 is a promising candidate technology in support of periodontal wound healing/regeneration. Carrier and rhGDF-5 dose optimization are necessary before further advancement of the technology towards clinical evaluation. [source] Distribution, abundance, and conservation of Vinaceous Amazons (Amazona vinacea) in Argentina and ParaguayJOURNAL OF FIELD ORNITHOLOGY, Issue 1 2007Kristina Cockle ABSTRACT Vinaceous Amazons (Amazona vinacea) are endemic to the Atlantic forest of southeastern Brazil, eastern Paraguay, and the province of Misiones in Argentina. We searched for Vinaceous Amazons throughout the western part of its range in Argentina and Paraguay during 1639 days of fieldwork from 1997 to 2006. These parrots have disappeared from most areas where they were historically recorded in these countries, and are now limited to a few sites in northeastern Paraguay and central Misiones (Argentina). We estimate the minimum remaining populations at 220 individuals in Paraguay and 203 individuals in Argentina. Important sites for the species are (1) the farming area from San Pedro to Tobuna (Misiones, Argentina) and (2) the Itaipú reserves complex and Reserva Natural Privada Itabó (Paraguay). In our surveys, Vinaceous Amazons were absent from the largest tracts of forest in Misiones, and were most often observed feeding, roosting, and nesting in small forest remnants and in agricultural areas that included forest fragments and isolated trees. Threats to amazons in these areas include nest poaching, forest clearing, and being shot as a crop pest. We confirmed 40 Vinaceous Amazons kept as pets in 35 homes between San Pedro and Tobuna. Environmental education and law enforcement are urgently needed to reduce threats in populated areas, and subsistence farmers need technical and logistical support to slow or stop the conversion of forest into cropland. Finally, additional study is needed to determine this amazon's habitat preferences, nest site requirements, and demography in different habitats. SINOPSIS El loro vinoso (Amazona vinacea) es endémico del bosque Atlántico del sudeste de Brasil, este de Paraguay, y la provincia de Misiones en Argentina. Buscamos esta especie durante 1639 días de trabajo de campo de 1997 a 2006, a lo largo de la porción oeste de su distribución, en Argentina y Paraguay. A. vinacea ha desaparecido de la mayor parte de las áreas donde ha sido registrada históricamente en estos paises, y permanece sólo en algunos pocos sitios del noroeste de Paraguay y del centro de Misiones (Argentina). Estimamos el tamaño mínimo de las poblaciones remanentes en 220 individuos en Paraguay y 203 individuos en Argentina. Los sitios importantes para la especie son: (1) la zona rural de San Pedro a Tobuna (Misiones, Argentina) y (2) el complejo de reservas de Itaipú y la Reserva Natural Privada Itabó (Paraguay). A. vinacea no fue encontrada en los tractos más grandes de bosque durante nuestras prospecciones en Misiones. Mayormente fue observada alimentándose, durmiendo y nidificando en pequeños remanentes boscosos y en hábitats antropogénicos. Las amenazas en estos hábitats incluyen robo de pichones de los nidos, deforestación, y cacería por daño a cultivos. Confirmamos la existencia de 40 ejemplares cautivos como mascotas en 35 hogares de San Pedro y Tobuna. Para reducir las amenazas se requieren urgentemente educación ambiental y fortalecimiento legal en las áreas pobladas. Es necesario proveer de apoyo técnico y logístico a los agricultores de subsistencia para reducir la conversión de bosques a cultivos. Finalmente, estudios futuros deberían tratar la preferencia de hábitat del loro, sus requerimientos de nidificación, y su demografía en distintos hábitats. [source] 122 Local to Coastal-Scale Macrophyte Community Structure: Surprizing Patterns and Possible MechanismsJOURNAL OF PHYCOLOGY, Issue 2003B. A. Menge Understanding large-scale patterns in ecological communities is a central goal of ecology, and yet, rigorous quantitative geographic data on distribution, abundance and diversity are almost totally lacking. Even in rocky intertidal habitats, our data on community structure are spatially and temporally limited, with most surveys limited to a few sites over short time periods. When linked to studies of community dynamics on similar scales, such studies should provide insights into the determinants of pattern at more relevant scales. In 1999 PISCO, the Partnership for Interdisciplinary Studies of Coastal Oceans, initiated survey programs aimed at determining patterns of community structure along the US west coast from Washington to Baja California. Sites are regularly spaced along the coast in a nested design, and were physically similar. Surveys used randomly placed quadrats in transects run parallel to shore in high, mid and low zones. Results show that, contrary to expectation, macroalgal diversity along the northern coast was higher, not lower than that along the southern coast. Possible factors associated with this unexpected pattern include along-coast variation in tidal amplitude, time of tide, thermal stress, upwelling intensity and resulting nutrient gradients, disturbance from storms or sand burial, and grazing. We review evidence relevant to these factors, and focus on the possible role of grazing, using field experiments done under differing oceanographic conditions along the Oregon coast as a model. Although short-term grazing rates can vary with oceanographic condition, we hypothesize that despite these results and those of many similar studies showing strong grazing effects on local spatial and short time scales, that bottom-up factors are stronger determinants of macroalgal community structure on larger spatial scales and longer time scales. [source] Brief communication: A probabilistic approach to age estimation from infracranial sequences of maturation,AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010Hélène Coqueugniot Abstract Infracranial sequences of maturation are commonly used to estimate the age at death of nonadult specimens found in archaeological, paleoanthropological, or forensic contexts. Typically, an age assessment is made by comparing the degree of long-bone epiphyseal fusion in the target specimen to the age ranges for different stages of fusion in a reference skeletal collection. While useful as a first approximation, this approach has a number of shortcomings, including the potential for "age mimicry," being highly dependent on the sample size of the reference sample and outliers, not using the entire fusion distribution, and lacking a straightforward quantitative way of combining age estimates from multiple sites of fusion. Here we present an alternative probabilistic approach based on data collected on 137 individuals, ranging in age from 7- to 29-years old, from a documented skeletal collection from Coimbra, Portugal. We then use cross validation to evaluate the accuracy of age estimation from epiphyseal fusion. While point estimates of age can, at least in some circumstances, be both accurate and precise based on the entire skeleton, or many sites of fusion, there will often be substantial error in these estimates when they derive from one or only a few sites. Because a probabilistic approach to age estimation from epiphyseal fusion is computationally intensive, we make available a series of spreadsheets or computer programs that implement the approach presented here. Am J Phys Anthropol 142:655,664, 2010. © 2010 Wiley-Liss, Inc. [source] What limits the spread of two congeneric butterfly species after their reintroduction: quality or spatial arrangement of habitat?ANIMAL CONSERVATION, Issue 6 2009F. Van Langevelde Abstract Population growth and spread of recently reintroduced species is crucial for the success of their reintroduction. We analysed what limits the spread of two congeneric butterfly species Maculinea teleius and Maculinea nausithous, over 10 years following their reintroduction. During this time, their distributions appeared to be limited to a few sites although it was thought that more suitable habitats were available. Thus, we question, does the quality or the spatial arrangement of their habitat limit their spread? Although adult individuals of both species can select high-quality plots, we show that selection of suitable plots in the area of reintroduction is spatially constrained. A low colonization probability of unoccupied distant plots of high quality was found for both species. The abandonment of occupied plots in Ma. teleius was also found to be dependent on the distance to occupied plots. We conclude that the spatial distribution of the two species during the 10 years following reintroduction was limited by the spatial arrangement of their habitat, rather than by the availability of high-quality plots. The spatial constraints in movement can explain observed source,sink structures when female butterflies deposit their eggs on low-quality plots. We conclude that although these species have very similar life histories, they require different approaches to their conservation due to subtle differences in adult habitat use and movement. Conservation of Ma. teleius should concentrate on improving local habitat quality, whereas conservation of Ma. nausithous is predicted to be more effective by creating a spatial network of suitable habitat plots, such as along road verges. [source] CHEMICAL COMPARISON OF RARE CHINESE WHITE POTTERY FROM FOUR SITES OF THE ERLITOU STATE: RESULTS AND ARCHAEOMETRICAL IMPLICATIONSARCHAEOMETRY, Issue 5 2010BAO-PING LI White pottery is among the most significant finds from China's earliest state, Erlitou (c. 1900,1500 bc). Samples were primarily discovered in small numbers from elite tombs of a few sites, leading to the hypothesis that they were made at only a few locations and then circulated regionally as prestige items. To facilitate determining provenances, we compare the ICP,MS trace elements and TIMS Sr isotopes of whiteware with two soil samples from Nanwa, a possible manufacturing site, and with shards found at three other sites: Erlitou, Huizui and Nanzhai. The Nanwa shards demonstrate special elemental and Sr isotopic features. Considering the chemical observation and archaeological background together, we propose that Nanwa was a centre for whiteware production, although the two soil samples we collected there were probably not the exact materials used. Some whiteware pieces from Erlitou, Huizui and Nanzhai fall in the chemical field defined by Nanwa samples, indicating that they were possibly made at Nanwa. Many other samples from these three sites plot outside the Nanwa field, implying they were probably not Nanwa products. This study demonstrates that while chemical sourcing is very useful, firm archaeological context must remain the cornerstone of such research. [source] | |||||||||||||