Vertical migration, feeding and colouration in the mesopelagic shrimp Sergestes arcticus

Intraspecific variation in vertical distribution, timing of vertical migration, and colouration of the mesopelagic shrimp Sergestes arcticus were studied in the >400 m deep part of Masfjorden, Norway. Very few individuals were caught in the upper strata during daytime, and larger individuals occurred deeper during the day than smaller ones. Vertical migration was prominent and no overall trend of increasing length with depth was found at night. Small individuals arrived in the upper layers earlier than larger ones. Animal colouration assessed by digital photography revealed significant variance in individual redness. Depth of capture was the most important factor explaining colouration, with increasing degree of redness with depth. Assessing the gut fullness of the transparent shrimps provided a rapid way of estimating feeding activity and showed that feeding took place mainly at night

Pristine levels of suspended sediment in large German river channels during the Anthropocene?

Suspended sediment is an integral part of riverine transport and functioning that has been strongly altered during the Anthropocene due to the overwhelming human pressure on soils, sediments, and the water cycle. Understanding the controls of changing suspended sediment in rivers is therefore vital for effective management strategies. Here we present results from a trend analysis of suspended sediments covering 62 monitoring stations along the German waterways (catchment sizes range between 2000 and 160 000 km2) with more than 440 000 water samples taken between 1990 and 2010. Based on daily monitoring of suspended sediment concentration (SSC), we found significant declines in mean annual SSC and annual suspended sediment loads (SSLs) at 49 of 62 monitoring stations totaling −0.92 mg L−1 yr−1. At some stations decreases during the 20 years represent up to 50 % of the long-term average SSC. Significant decreases in SSC are associated with declining SSL despite an increase in sheet and rill erosion by almost 150 % derived from modeling due to changes in land use and management as well as rainfall erosivity. The contemporary suspended sediment loads of the Rhine at the German–Dutch border are approaching the natural base level of ∼1 Mt yr−1, which was reached by the Rhine during the mid-Holocene when the suspended sediment load was adjusted to the Holocene climatic conditions and before the onset of increased loads due to human-induced land use changes in the Rhine catchment. At this point we can only speculate regarding potential reasons for a decline in sediment transport in larger rivers despite erosion increase. We argue that increased sediment retention in upstream headwaters is presumably the major reason for declining SSC in the large river channels studied.</p

Intrinsic water-use efficiency of temperate seminatural grassland has increased since 1857: an analysis of carbon isotope discrimination of herbage from the Park Grass Experiment

A 150-year-long record of intrinsic water-use efficiency (W-i) was derived from community-level carbon isotope discrimination (13 delta) in the herbage of the unfertilized, unlimed control treatment (plot 3) of the Park Grass Experiment at Rothamsted (England) between 1857 and 2007. 13 delta during spring growth (first cut harvested in June) averaged 21.0 parts per thousand (+/- 0.5 parts per thousand SD) and has not shown a long-term trend (P=0.5) since 1857. 13 delta of summer/autumn growth (second cut harvested between September and November) increased from 21.3 parts per thousand to 22.0 parts per thousand (P < 0.001) between 1875 and 2007. W-i during spring growth has therefore increased by 33% since the beginning of the experiment, and W-i of summer/autumn growth has increased by 18%. The variation in 13 delta was mainly related to weather conditions. Plant available soil water explained 51% and 40% of the variation in spring growth 13 delta and summer/autumn growth 13 delta, respectively. In the 1857-2007 period yields have not increased, suggesting that community-level photosynthesis has not increased either. Therefore, the increased W-i probably resulted from a decreased stomatal conductance. Vapour pressure deficit (VPD) during spring growth (March-June) has not changed since 1915, meaning that instantaneous water-use efficiency (W-t) in spring time has increased and transpiration has probably decreased, provided that leaf temperature followed air temperature. Conversely, VPD in the months between the first and second cut has increased by 0.07 kPa since 1915, offsetting the effect of increased W-i on W-t during summer and early autumn. Our results suggest that vegetation has adjusted physiologically to elevated CO2 by decreasing stomatal conductance in this nutrient-limited grassland

Enhanced attraction between drops carrying fluctuating charge distributions

The electrostatic force between conductive spheres is always attractive at small separations, irrespective of their mean charge, when the charge on the spheres is constant. In many situations, the charge may not be fixed, such as for water drops in the natural atmosphere which vary in size and charge. We show that the attractive force between charged conductive spheres increases with increasing charge variance. The importance of this unrecognized electrostatic effect between water drops is evaluated for its potential to enhance rain formation

Functional phage display of leech-derived tryptase inhibitor (LDTI): construction of a library and selection of thrombin inhibitors

The recombinant phage antibody system pCANTAB 5E has been used to display functionally active leech-derived tryptase inhibitor (LDTI) on the tip of the filamentous M13 phage, A limited combinatorial library of 5.2 x 10(4) mutants was created with a synthetic LDTI gene, using a degenerated oligonucleotide and the pCANTAB 5E phagemid. the mutations were restricted to the P1-P4' positions of the reactive site. Fusion phages and appropriate host strains containing the phagemids were selected after binding to thrombin and DNA sequencing. the variants LDTI-2T (K8R, I9V, S10, K11W, P12A), LDTI-5T (K8R, I9V, S10, K11S, P12L) and LDTI-10T (K8R, I9L, S10, K11D, P12I) were produced with a Saccharomyces cerevisiae expression system. the new inhibitors, LDTI-2T and -5T, prolong the blood clotting time, inhibit thrombin (Ki 302 nM and 28 nM) and trypsin (K-i 6.4 nM and 2.1 nM) but not factor Xa, plasma kallikrein or neutrophil elastase, the variant LDTI-10T binds to thrombin but does not inhibit it, the relevant reactive site sequences of the thrombin inhibiting variants showed a strong preference for arginine in position P1 (K8R) and for valine in P1' (I9V), the data indicate further that LDTI-5T might be a model candidate for generation of active-site directed thrombin inhibitors and that LDTI in general may be useful to generate specific inhibitors suitable for a better understanding of enzyme-inhibitor interactions. (C) 1999 Federation of European Biochemical Societies.UNIFESP, Dept Bioquim, EPM, BR-04044020 São Paulo, BrazilUniv Munich, Klinikum Innenstadt, Chirurg Klin & Poliklin, Klin Chem & Klin Biochem Abt, D-8000 Munich, GermanyUNIFESP, Dept Med, Disciplina Hematol, EPM, BR-04044020 São Paulo, BrazilUNIFESP, Dept Bioquim, EPM, BR-04044020 São Paulo, BrazilUNIFESP, Dept Med, Disciplina Hematol, EPM, BR-04044020 São Paulo, BrazilWeb of Scienc

Replacement therapy for bleeding episodes in factor VII deficiency: A prospective evaluation

Patients with inherited factor VII (FVII) deficiency display different clinical phenotypes requiring ad hoc management. This study evaluated treatments for spontaneous and traumatic bleeding using data from the Seven Treatment Evaluation Registry (STER). One-hundred one bleeds were analysed in 75 patients (41 females; FVII coagulant activity <1-20%). Bleeds were grouped as haemarthroses (n=30), muscle/subcutaneous haematomas (n=16), epistaxis (n=12), gum bleeding (n=13), menorrhagia (n=16), central nervous system (CNS; n=9), gastrointestinal (GI; n=2) and other (n=3). Of 93 evaluable episodes, 76 were treated with recombinant, activated FVII (rFVIIa), eight with fresh frozen plasma (FFP), seven with plasma-derived FVII (pdFVII) and two with prothrombin-complex concentrates. One-day replacement therapy resulted in very favourable outcomes in haemarthroses, and was successful in muscle/subcutaneous haematomas, epistaxis and gum bleeding. For menorrhagia, single- or multiple-dose schedules led to favourable outcomes. No thrombosis occurred; two inhibitors were detected in two repeatedly treated patients (one post-rFVIIa, one post-pdFVII). In FVII deficiency, most bleeds were successfully treated with single 'intermediate' doses (median 60 µg/kg) of rFVIIa. For the most severe bleeds (CNS, GI) short- or long-term prophylaxis may be optimalPatients with inherited factor VII (FVII) deficiency display different clinical phenotypes requiring ad hoc management. This study evaluated treatments for spontaneous and traumatic bleeding using data from the Seven Treatment Evaluation Registry (STER). One-hundred one bleeds were analysed in 75 patients (41 females; FVII coagulant activity <1-20%). Bleeds were grouped as haemarthroses (n=30), muscle/subcutaneous haematomas (n=16), epistaxis (n=12), gum bleeding (n=13), menorrhagia (n=16), central nervous system (CNS; n=9), gastrointestinal (GI; n=2) and other (n=3). Of 93 evaluable episodes, 76 were treated with recombinant, activated FVII (rFVIIa), eight with fresh frozen plasma (FFP), seven with plasma-derived FVII (pdFVII) and two with prothrombin-complex concentrates. One-day replacement therapy resulted in very favourable outcomes in haemarthroses, and was successful in muscle/subcutaneous haematomas, epistaxis and gum bleeding. For menorrhagia, single- or multiple-dose schedules led to favourable outcomes. No thrombosis occurred; two inhibitors were detected in two repeatedly treated patients (one postrFVIIa, one post-pdFVII). In FVII deficiency, most bleeds were successfully treated with single 'intermediate' doses (median 60 μg/kg) of rFVIIa. For the most severe bleeds (CNS, GI) short- or long-term prophylaxis may be optimal. © Schattauer 2013

Decreased Type I Interferon Production by Plasmacytoid Dendritic Cells Contributes to Severe Dengue

The clinical presentation of dengue virus (DENV) infection is variable. Severe complications mainly result from exacerbated immune responses. Type I interferons (IFN-I) are important in antiviral responses and form a crucial link between innate and adaptive immunity. Their contribution to host defense during DENV infection remains under-studied, as direct quantification of IFN-I is challenging. We combined ultra-sensitive single-molecule array (Simoa) digital ELISA with IFN-I gene expression to elucidate the role of IFN-I in a well-characterized cohort of hospitalized Cambodian children undergoing acute DENV infection. Higher concentrations of type I IFN proteins were observed in blood of DENV patients, compared to healthy donors, and correlated with viral load. Stratifying patients for disease severity, we found a decreased expression of IFN-I in patients with a more severe clinical outcome, such as dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). This was seen in parallel to a correlation between low IFNα protein concentrations and decreased platelet counts. Type I IFNs concentrations were correlated to frequencies of plasmacytoid DCs, not DENV-infected myloid DCs and correlated inversely with neutralizing anti-DENV antibody titers. Hence, type I IFN produced in the acute phase of infection is associated with less severe outcome of dengue disease

Variation in carbon isotope discrimination in Cleistogenes squarrosa (Trin.) Keng: patterns and drivers at tiller, local, catchment, and regional scales

Understanding the patterns and drivers of carbon isotope discrimination in C4 species is critical for predicting the effects of global change on C3/C4 ratio of plant community and consequently on ecosystem functioning and services. Cleistogenes squarrosa (Trin.) Keng is a dominant C4 perennial bunchgrass of arid and semi-arid ecosystems across the Mongolian plateau of the Eurasian steppe. Its carbon isotope discrimination (13Δ) during photosynthesis is relatively large among C4 species and it is variable. Here the 13Δ of C. squarrosa and its potential drivers at a nested set of scales were examined. Within cohorts of tillers, 13Δ of leaves increased from 5.1‰ to 8.1‰ from old to young leaves. At the local scale, 13Δ of mature leaves varied from 5.8‰ to 8.4‰, increasing with decreasing grazing intensity. At the catchment scale, 13Δ of mature leaves varied from 6.2‰ to 8.5‰ and increased with topsoil silt content. At the regional scale, 13Δ of mature leaves varied from 5.5‰ to 8.9‰, increasing with growing-season precipitation. At all scales, 13Δ decreased with increasing leaf nitrogen content (Nleaf). Nleaf was positively correlated with grazing intensity and leaf position along tillers, but negatively correlated with precipitation. The presence of the correlations across a range of different environmental contexts strongly implicates Nleaf as a major driver of 13Δ in C. squarrosa and, possibly, other C4 species