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To restore lateral connectivity in highly regulated river-floodplain systems, it has become necessary to implement localized, 'managed' connection flows, made possible using floodplain irrigation infrastructure. These managed flows contrast with 'natural', large-scale, overbank flood pulses. We compared the effects of a managed and a natural connection event on (i) the composition of the large-bodied fish community and (ii) the structure of an endangered catfish population of a large floodplain lake. The change in community composition following the managed connection was not greater than that exhibited between seasons or years during disconnection. By contrast, the change in fish community structure following the natural connection was much larger than that attributed to background, within- and between-year variability during disconnection. Catfish population structure only changed significantly following the natural flood. While the natural flood increased various population rates of native fishes, it also increased those of non-native carp, a pest species. To have a positive influence on native biodiversity, environmental flows may need to be delivered to floodplains in a way that simulates the properties of natural flood pulses. A challenge, however, will be managing river-floodplain connectivity to benefit native more than non-native species. Pour retablir la connectivite de reseaux fluviaux fortement regularises de plaine inondable, il est devenu necessaire de mettre en place des debits de connexion << geres >> localises rendus possibles par les infrastructures d'irrigation dans la plaine inondable. Ces ecoulements se distinguent des debordements transitoires << naturels >> a grande echelle associes aux crues. Nous avons compare les effets d'evenements de connexion gere, d'une part, et naturel, d'autre part, sur (i) la composition de la communaute de gros poissons et (ii) la structure d'une population menacee de barbues dans un grand lac de plaine inondable. La modification de la composition de la communaute apres l'evenement de connexion gere n'etait pas plus importante que la variabilite observee d'une saison a l'autre ou d'une annee a l'autre en situation de deconnexion. En revanche, la modification de la structure de la communaute de poissons apres l'evenement de connexion naturel etait beaucoup plus importante que celle attribuable a la variabilite intersaisonniere et interannuelle de fond en situation de deconnexion. La structure de la population de barbues n'a change de maniere significative qu'apres la crue naturelle. Si cette crue naturelle a entrame une augmentation des taux de population de divers poissons indigenes, elle s'est egalement traduite par une augmentation du taux de population des carpes, une espece parasite non indigene. Il se pourrait que, pour avoir une incidence positive sur la biodiversite indigene, les debits environnementaux dans les plaines inondables doivent simuler les proprietes des crues naturelles. L'un des defis que cela presente consiste a gerer la connectivite hydrologique dans la plaine inondable d'une maniere qui profite plus aux especes indigenes qu'aux especes introduites. [Traduit par la Redaction], Introduction Floodplain wetlands support high levels of aquatic biodiversity, but are among the most threatened habitats on earth (Bunn and Arthington 2002; Opperman et al. 2009; Tockner and Stanford 2002). [...]

Abstract: The objective of the present study was to examine the preva-lence of self-reported autoimmune diseases among offspring of type 1 fathers, type 1 diabetic mothers, and non-diabetic parents. Type 1 dia-betic probands (n265; mean age42 yr), who were ascertained from the Childrens Hospital of Pittsburgh Registry for 1950--1964, recently participated in the Familial Autoimmune and Diabetes Study. Non-dia-betic probands (n96), identified from voter registration lists and matched by age, race, median income, and duration of residence in the Pittsburgh area, were also enrolled. Offspring of type 1 diabetic probands were more likely to have a reported autoimmune disease (5.8% vs. 2.4%; p0.067) than offspring of non-diabetic probands. Half the cases in the diabetic families were disorders other than type 1 diabetes, (e.g., rheumatoid arthritis, Crohns disease, etc.). Stratification by parental gender revealed a marginally higher risk for type 1 diabetes among offspring of type 1 diabetic fathers compared to mothers (4.9% vs. 3.4%; p0.38, respectively, through age 20 yr). However, the risk for other autoimmune disorders was statistically significantly increased among offspring of type 1 diabetic mothers (0% vs. 6.2%; p0.02, respectively, through age 20 yr). These data suggest that offspring of type 1 diabetic parents may be at high risk of developing other autoim-mune disorders during childhood, with pediatric diabetes representing the tip of an autoimmune iceberg. The observed risk differences by parental gender, which have also been reported for other autoimmune disorders, warrant further investigation. [ABSTRACT FROM AUTHOR]

An exceptionally severe case of biodeterioration in a textile floorcovering is described. Examination b; light and scanning electron microscopy reveals unusual detail of the degrading organisms and their effects, some of which have not been reported before to the authors' knowledge. The images and microscopical techniques are compared and the causative circumstances of the degradation considered. [ABSTRACT FROM AUTHOR]