The effectiveness of aquatic plants as surrogates for wider biodiversity in standing fresh waters

1. Freshwaters are among the most globally threatened habitats and their biodiversity is declining at an unparalleled rate. In an attempt to slow this decline, multiple approaches have been used to conserve, restore or enhance waterbodies. However, evaluating their effectiveness is time‐consuming and expensive. Identifying species or assemblages across a range of ecological conditions that can provide a surrogate for wider freshwater biodiversity is therefore of significant value for conservation management and planning. 2. For lakes and ponds in three contrasting landscapes of Britain (lowland agricultural, eastern England; upland, north‐west England; urban, central Scotland) we examined the link between macrophyte species, macrophyte morpho‐group diversity (an indicator of structural diversity) and the richness of three widespread aquatic macroinvertebrate groups (molluscs, beetles, and odonates) using structural equation modelling. We hypothesised that increased macrophyte richness and, hence, increased vegetation structural complexity, would increase macroinvertebrate richness after accounting for local and landscape conditions. 3. We found that macrophyte richness, via macrophyte morpho‐group diversity, was an effective surrogate for mollusc, beetle, and odonate richness in ponds after accounting for variation caused by physical variables, water chemistry, and surrounding land use. However, only mollusc richness could be predicted by macrophyte morpho‐group diversity in lakes, with no significant predicted effect on beetles or odonates. 4. Our results indicate that macrophyte morpho‐group diversity can be viewed as a suitable surrogate of macroinvertebrate biodiversity across diverse landscapes, particularly in ponds and to a lesser extent in lakes. This has important implications for the restoration, conservation, and creation of standing water habitats and for assessing their effectiveness in addressing the decline of global freshwater biodiversity. Management actions prioritising the development of species‐rich and structurally diverse macrophyte assemblages will be likely to benefit wider freshwater biodiversity

Communities of gastrointestinal helminths of fish in historically connected habitats: habitat fragmentation effect in a carnivorous catfish Pelteobagrus fulvidraco from seven lakes in flood plain of the Yangtze River, China

<p>Abstract</p> <p>Background</p> <p>Habitat fragmentation may result in the reduction of diversity of parasite communities by affecting population size and dispersal pattern of species. In the flood plain of the Yangtze River in China, many lakes, which were once connected with the river, have become isolated since the 1950s from the river by the construction of dams and sluices, with many larger lakes subdivided into smaller ones by road embankments. These artificial barriers have inevitably obstructed the migration of fish between the river and lakes and also among lakes. In this study, the gastrointestinal helminth communities were investigated in a carnivorous fish, the yellowhead catfish <it>Pelteobagrus fulvidraco</it>, from two connected and five isolated lakes in the flood plain in order to detect the effect of lake fragmentation on the parasite communities.</p> <p>Results</p> <p>A total of 11 species of helminths were recorded in the stomach and intestine of <it>P. fulvidraco </it>from seven lakes, including two lakes connected with the Yangtze River, i.e. Poyang and Dongting lakes, and five isolated lakes, i.e. Honghu, Liangzi, Tangxun, Niushan and Baoan lakes. Mean helminth individuals and diversity of helminth communities in Honghu and Dongting lakes was lower than in the other five lakes. The nematode <it>Procamallanus fulvidraconis </it>was the dominant species of communities in all the seven lakes. No significant difference in the Shannon-Wiener index was detected between connected lakes (0.48) and isolated lakes (0.50). The similarity of helminth communities between Niushan and Baoan lakes was the highest (0.6708), and the lowest was between Tangxun and Dongting lakes (0.1807). The similarity was low between Dongting and the other lakes, and the similarity decreased with the geographic distance among these lakes. The helminth community in one connected lake, Poyang Lake was clustered with isolated lakes, but the community in Dongting Lake was separated in the tree.</p> <p>Conclusion</p> <p>The similarity in the helminth communities of this fish in the flood-plain lakes may be attributed to the historical connection of these habitats and to the completion of the life-cycles of this fish as well as the helminth species within the investigated habitats. The diversity and the digenean majority in the helminth communities can be related to the diet of this fish, and to the lacustrine and macrophytic characters of the habitats. The lake isolation from the river had little detectable effect on the helminth communities of the catfish in flood-plain lakes of the Yangtze River. The low similarities in helminth communities between the Dongting Lake and others may just be a reflection of its unique water environment and anthropogenic alterations or fragmentation in this lake.</p

Global characterization of interferon regulatory factor (IRF) genes in vertebrates: Glimpse of the diversification in evolution

<p>Abstract</p> <p>Background</p> <p>Interferon regulatory factors (IRFs), which can be identified based on a unique helix-turn-helix DNA-binding domain (DBD) are a large family of transcription factors involved in host immune response, haemotopoietic differentiation and immunomodulation. Despite the identification of ten IRF family members in mammals, and some recent effort to identify these members in fish, relatively little is known in the composition of these members in other classes of vertebrates, and the evolution and probably the origin of the IRF family have not been investigated in vertebrates.</p> <p>Results</p> <p>Genome data mining has been performed to identify any possible IRF family members in human, mouse, dog, chicken, anole lizard, frog, and some teleost fish, mainly zebrafish and stickleback, and also in non-vertebrate deuterostomes including the hemichordate, cephalochordate, urochordate and echinoderm. In vertebrates, all ten IRF family members, i.e. IRF-1 to IRF-10 were identified, with two genes of IRF-4 and IRF-6 identified in fish and frog, respectively, except that in zebrafish exist three IRF-4 genes. Surprisingly, an additional member in the IRF family, IRF-11 was found in teleost fish. A range of two to ten IRF-like genes were detected in the non-vertebrate deuterostomes, and they had little similarity to those IRF family members in vertebrates as revealed in genomic structure and in phylogenetic analysis. However, the ten IRF family members, IRF-1 to IRF-10 showed certain degrees of conservation in terms of genomic structure and gene synteny. In particular, IRF-1, IRF-2, IRF-6, IRF-8 are quite conserved in their genomic structure in all vertebrates, and to a less degree, some IRF family members, such as IRF-5 and IRF-9 are comparable in the structure. Synteny analysis revealed that the gene loci for the ten IRF family members in vertebrates were also quite conservative, but in zebrafish conserved genes were distributed in a much longer distance in chromosomes. Furthermore, all ten different members are clustered in respectively different clades; but the IRF-11 was clustered with one in sea urchin.</p> <p>Conclusions</p> <p>In vertebrates, the ten well-characterized IRF family members shared a relatively high degree of similarity in genomic structure and syntenic gene arrangement, implying that they might have been evolved in a similar pattern and with similar selective pressure in different classes of vertebrates. Genome and/or gene duplication, and probably gene shuffling or gene loss might have occurred during the evolution of these IRF family members, but arrangement of chromosome or its segment might have taken place in zebrafish. However, the ten IRF family members in vertebrates and those IRF-like genes in non-vertebrate deuterostomes were quite different in those analyzed characters, as they might have undergone different patterns of evolution.</p

Isolation and characterization of polymorphic microsatellite loci in Wuchang bream (Megalobrama amblycephala)

Wuchang bream (Megalobrama amblycephala) is an economically important fish in China. From a (GT)(13)-enriched genomic library, 20 microsatellites were developed. Nine of these 20 loci were polymorphic in a test population with allele numbers ranging from two to four, and the observed and expected heterozygosities ranging from 0.2609 to 0.7826 and from 0.3739 to 0.7546, respectively. In the cross-species amplifications, six of these nine loci were also polymorphic in white amur bream (Parabramis pekinensis). These polymorphic microsatellite loci are potentially useful for population genetics of Wuchang bream and its closely related species.Wuchang bream (Megalobrama amblycephala) is an economically important fish in China. From a (GT)(13)-enriched genomic library, 20 microsatellites were developed. Nine of these 20 loci were polymorphic in a test population with allele numbers ranging from two to four, and the observed and expected heterozygosities ranging from 0.2609 to 0.7826 and from 0.3739 to 0.7546, respectively. In the cross-species amplifications, six of these nine loci were also polymorphic in white amur bream (Parabramis pekinensis). These polymorphic microsatellite loci are potentially useful for population genetics of Wuchang bream and its closely related species

Introgression evidence and phylogenetic relationships among three (Para)Misgurnus species as revealed by mitochondrial and nuclear DNA markers

The taxonomy of (Para)Misgurnus genera is still debated. We therefore used mitochondrial and nuclear DNA markers to analyze the phylogenetic relationships among Misgurnus anguillicaudatus, Paramisgurnus dabryanus and Misgurnus fossilis. Differing phylogenetic signals from mitochondrial and nuclear marker data suggest an introgression event in the history of M. anguillicaudatus and M. mohoity. No substantial genetic evidence was found that Paramisgurnus dabryanus should be classified as a separate genus

Impacts of cascade run-of-river dams on benthic diatoms in the Xiangxi River, China

The ecological effects of small run-of-river dams on aquatic ecosystems are poorly understood, especially on downstream benthic algal communities. We examined impacts of such dams on the benthic diatom community at a regional scale in the Xiangxi River, China. A total of 90 sites were visited, which were divided into five habitats (H1-H5) according to impact extent of each dam. Using partial least squares (PLS) modeling, we developed two predictive models (diatom species richness and total diatom density) based on environmental variables of an unregulated habitat (H1). These models were then used to predict species richness and total densities at impacted habitats (H2-H5) and residuals, i.e. the differences between observed and predicted values, were used to evaluate impact strength of flow regulation. Significant impacts of flow regulation on diatom species richness were detected at three impacted habitats (H3-H5), where observed species richness were significantly higher-70.6, 63.9 and 46.6%, respectively-than predicted values. Then, possible mechanisms for observed impacts were discussed. Further research is necessary to address the potential negative impacts of cascade run-of-river dams on other aquatic organisms in different seasons, and to explore more appropriate mechanisms for such impacts, which may lead to sustainable management strategies and help to determine the optimal ecological water requirement for the Xiangxi River

Icefish (Salangidae) as an indicator of anthropogenic pollution in freshwater systems using nitrogen isotope analysis

We investigated differences in delta N-15 of seston and icefishes from seven freshwater ecosystems with different trophic states in China. An increase of seston delta N-15 values was accompanied by an increase of total nitrogen and phosphorus concentrations. Significantly positive correlations were observed between delta N-15 of icefishes and delta N-15 of seston, total nitrogen and phosphorus concentrations. This study demonstrated that icefishes could be preferred indicators of anthropogenic contamination in test systems because they integrated waste inputs over long time periods and reflected the movement of waste through the pelagic food chain.We investigated differences in delta N-15 of seston and icefishes from seven freshwater ecosystems with different trophic states in China. An increase of seston delta N-15 values was accompanied by an increase of total nitrogen and phosphorus concentrations. Significantly positive correlations were observed between delta N-15 of icefishes and delta N-15 of seston, total nitrogen and phosphorus concentrations. This study demonstrated that icefishes could be preferred indicators of anthropogenic contamination in test systems because they integrated waste inputs over long time periods and reflected the movement of waste through the pelagic food chain

Visual Analysis of a Cold Rolling Process Using Data-Based Modeling

International Conference on Engineering Applications of Neural Networks (13th. 2012. Coventry Univ, Otaniemi, Finland

Systematic evaluation of pembrolizumab dosing in patients with advanced non-small cell lung cancer

International audienceBACKGROUND: In the phase I KEYNOTE-001 study, pembrolizumab demonstrated durable antitumor activity in patients with advanced non-small cell lung cancer (NSCLC). We sought to characterize the relationship between pembrolizumab dose, exposure, and response to define an effective dose for these patients. METHODS: Patients received pembrolizumab 2 mg/kg every 3 weeks (Q3W) (n=55), 10 mg/kg Q3W (n=238), or 10 mg/kg Q2W (n=156). Response (RECIST v1.1) was assessed every 9 weeks. The relationship between the estimated pembrolizumab area under the concentration-time curve at steady-state over 6 weeks (AUCss-6weeks) and the longitudinal change in tumor size (sum of longest diameters) was analyzed by regression and nonlinear mixed effects modeling. This model was simultaneously fit to all tumor size data, then used to simulate response rates, normalizing the trial data across dose for prognostic covariates (tumor PD-L1 expression and EGFR mutation status). The exposure-safety relationship was assessed by logistic regression of pembrolizumab AUCss-6weeks versus occurrence of adverse events of interest based on their immune etiology. RESULTS: Overall response rates were 15% (95% confidence interval [CI] 7%-28%) at 2 Q3W, 25% (18%-33%) at 10 Q3W, and 21% (95% CI 14% to 30%) at 10 Q2W. Regression analyses of percentage change from baseline in tumor size versus AUCss-6week indicated a flat relationship (regression slope P\textgreater0.05). Simulations showed the exposure-response relationship to be similarly flat, thus indicating that the lowest evaluated dose of 2 mg/kg Q3W to likely be at or near the efficacy plateau. Exposure-safety analysis showed the adverse event incidence to be similar among the clinically tested doses. CONCLUSIONS: No significant exposure dependency on efficacy or safety was identified for pembrolizumab across doses of 2 mg/kg to 10 mg/kg. These results support the use of a 2-mg/kg Q3W dosage in patients with previously treated, advanced NSCLC.ClinicalTrials.gov registry: NCT0129582

Eliciting reflections on caring theory in elderly caring practice

Caring theories are the description and conceptualization of the care that is given in caring practise by nurses and other professional caregivers with the aim of verbalizing and communicating caring phenomena. Intermittently, a theory –practice gap is given expression- that theory does not go along with clinical practice in caring