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21.
Observations of historical and recent phytoplankton samples from five hypereutrophic Florida lakes indicate that nitrogen-fixing cyanobacteria in the genus Cylindrospermopsis Seenayya et Subba Raju have entered these water-bodies sometime in the last 30 years. Cylindrospermopsis forms a year-round bloom in one of the five lakes, dominates seasonally in another, and is at least at times an important component of the phytoplankton community in the remaining three. The increase in abundance of Cylindrospermopsis in Florida lakes could have implications for water management.  相似文献   
22.
Sensitive biological measures of river ecosystem quality are needed to assess, maintain or restore ecological conditions of water bodies. Since our understanding of these complex systems is imperfect, decision-making requires recognizing uncertainty. In this study, a new predictive multi-metric index based on fish functional traits was developed to assess French rivers. Information on fish assemblage structure, local environment and human-induced disturbances of 1654 French river sites was compiled. A Bayesian framework was used to predict theoretical metric values in absence of human pressure and to estimate the uncertainty associated with these predictions. The uncertainty associated with the index score gives the confidence associated with the evaluation of site ecological conditions.Among the 228 potential metrics tested, only 11 were retained for the index computation. The final index is independent from natural variability and sensitive to human-induced disturbances. In particular, it is affected by the accumulation of different degradations and specific degradations including hydrological perturbations. Predictive uncertainty is globally lower for IPR+ than for underlying metrics.This new methodology seems appropriate to develop bio-indication tools accounting for uncertainty related to reference condition definition and could be extended to other biological groups and areas. Our results support the use of multi-metric indexes to assess rivers and strengthen the idea that examination of uncertainty could contribute greatly to the improvement of the assessment power of bio-indicators.  相似文献   
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The European Common Agricultural Policy still follows its primary goals, i.e. quality food at affordable prices and a decent standard of living for farmers, fifty years after its adoption. Moreover, this policy adapts to the changing needs of society and the new challenges, mostly preservation of the environment, nature and biodiversity in rural areas. Although the Common Agricultural Policy receives the largest share of European budget, the funds are decreasing over time, especially direct payments, which aim to provide basic income support to farmers in the European Union. On the other hand, agri-environmental payments are gaining importance. Policy decision-makers should be interested in the question of impacts of growing eco-conditionality of agricultural spending. New insights would help them to be successful in achieving the goals of sustainable agriculture. The purpose of this paper is to estimate the impacts of production support payments and rural development payments on the quality of groundwater. We use the small EU country Slovenia as an example. The baseline indicators are the level of nitrates and pesticides in groundwater, while the impacts were estimated using spatial error model. The results show that direct payments, coupled subsidies and investment grants raise the level of pesticides in groundwater, but do not have any statistically significant impact on the level of nitrates in groundwater. Furthermore, we did not find any statistically significant effects of agri-environmental payments on decrease of groundwater pollution with nitrates. However, our findings revealed that agri-environmental payments are effective in reducing pesticides in groundwater, although only to a limited extent. These results imply a problem of insufficient targeting of agri-environmental measures on the one hand, and suggest that greening of direct payments is necessary and entirely justified.  相似文献   
25.
Drug resistance is a critical obstacle to effective treatment in patients with chronic myeloid leukemia. To understand the underlying resistance mechanisms in response to imatinib mesylate (IMA) and adriamycin (ADR), the parental K562 cells were treated with low doses of IMA or ADR for 2 months to generate derivative cells with mild, intermediate, and severe resistance to the drugs as defined by their increasing resistance index. PulseDIA-based (DIA [data-independent acquisition]) quantitative proteomics was then employed to reveal the proteome changes in these resistant cells. In total, 7082 proteins from 98,232 peptides were identified and quantified from the dataset using four DIA software tools including OpenSWATH, Spectronaut, DIA-NN, and EncyclopeDIA. Sirtuin signaling pathway was found to be significantly enriched in both ADR-resistant and IMA-resistant K562 cells. In particular, isocitrate dehydrogenase (NADP(+)) 2 was identified as a potential drug target correlated with the drug resistance phenotype, and its inhibition by the antagonist AGI-6780 reversed the acquired resistance in K562 cells to either ADR or IMA. Together, our study has implicated isocitrate dehydrogenase (NADP(+)) 2 as a potential target that can be therapeutically leveraged to alleviate the drug resistance in K562 cells when treated with IMA and ADR.  相似文献   
26.
Summary Under the ?Bois plus? scheme, the CTBA is currently developing a third party certification, based on the Scrivener law, with the aim of defending the consumers' interests. At this early stage, wood preservatives and treated wood are checked for the efficacy of treatments in order to ensure the stability and security of works in buildings and civil engineering. According to the different classes of risks in service, ?Bois plus? provides the most adeguate level of protection. In the close future, the industry is planning to incorporate, with the help of the CTBA and experts, health criteria within the frame of the ?Bois plus? certification scheme. The means could beSafety indexes, which are objectives of quality for professionals.Safety indexes are concentrations of substances in wood which can be taken as safe for humans and the general environment, while still toxic for the wood pests. This attractive experience aims to make with the brandname ?Bois plus? a synonym of efficacy and safety. This approach meets the essential requirements 1, 3, 4 of the 89/106 EEC directive: mechanical resistance and stability/hygiene, health and environment/safety in use.  相似文献   
27.
An extensive review of the literature describing epiphytes on submerged aquatic vegetation (SAV), especially seagrasses, was conducted in order to evaluate the evidence for response of epiphyte metrics to increased nutrients. Evidence from field observational studies, together with laboratory and field mesocosm experiments, was assembled from the literature and evaluated for a hypothesized positive response to nutrient addition. There was general consistency in the results to confirm that elevated nutrients tended to increase the load of epiphytes on the surface of SAV, in the absence of other limiting factors. In spite of multiple sources of uncontrolled variation, positive relationships of epiphyte load to nutrient concentration or load (either nitrogen or phosphorus) often were observed along strong anthropogenic or natural nutrient gradients in coastal regions. Such response patterns may only be evident for parts of the year. Results from both mesocosm and field experiments also generally support the increase of epiphytes with increased nutrients, although outcomes from field experiments tended to be more variable. Relatively few studies with nutrient addition in mesocosms have been done with tropical or subtropical species, and more such controlled experiments would be helpful. Experimental duration influenced results, with more positive responses of epiphytes to nutrients at shorter durations in mesocosm experiments versus more positive responses at longer durations in field experiments. In the field, response of epiphyte biomass to nutrient additions was independent of climate zone. Mesograzer activity was a critical covariate for epiphyte response under experimental nutrient elevation, but the epiphyte response was highly dependent on factors such as grazer identity and density, as well as nutrient and ambient light levels. The balance of evidence suggests that epiphytes on SAV will be a useful indicator of persistent nutrient enhancement in many situations. Careful selection of appropriate temporal and spatial constraints for data collection, and concurrent evaluation of confounding factors will help increase the signal to noise ratio for this indicator.  相似文献   
28.
The present research was conducted in district Jhang, Pakistan, to evaluate the concentration of metals/metalloids in soil and pumpkin (Cucurbita maxima) irrigated with domestic wastewater. Data revealed that the levels of metals and metalloids in soil samples from two different sites were below the safe limits except Cd, whereas, in the vegetable, the concentrations of As, Se, Ni, Mo, Pb, Mn, and Cu were above the safe limits. The levels of 12 metals and metalloids in the soil were ranged between 0.14 to 22.76 mg/kg at site-I and 0.16 to 22.13 mg/kg at site-II. The levels of these metals in the vegetable were found 0.35 to 61.13 mg/kg at site-I and 0.31 to 53.63 mg/kg at site-II. The transfer factor at both sites was highest for As and Co. The pollution load index recorded for Se, Cu, Cd, Mo, Pb, and Co was greater than 1. The daily intake of As, Mn, and Mo was above the oral reference dose, which reflects that the intake of pumpkin is not safe for the inhabitants of the selected sites. The control measures should be taken to phytoextract heavy metals and metalloids from polluted sites so as to reduce the health risks.  相似文献   
29.
Due to the intensive mixing polymictic lakes should be homogenous. However, morphometric diversity and high water dynamics contribute to the differentiation of many parameters in various areas of the lakes. This study analyzes both phytoplankton and zooplankton to assess differences in water quality along the north–south axis of the longest lake in Poland. New phytoplankton indicators were applied for determining the lake's ecological status: the Q index based on functional groups and the PMPL (Phytoplankton Metric for Polish Lakes) index based on phytoplankton biomass. TSIROT index (Rotifer Trophic State Index), which comprises the percentage of species indicating a high trophic state in the indicatory group and the percentage of bacteriovorus in the Rotifera population, was used for zooplankton analysis.TP content was different at different sites – we observed its gradual increase from the south to the north. Spatial variation of phosphorus did not considerably affect plankton diversity. The phytoplankton was dominated by Oscillatoriales, typical of shallow, well-mixed eutrophic lakes. The ecological status of the lake based on the EQR (Ecological Quality Ratio) was poor or moderate. The zooplankton was dominated by rotifers (at almost all sites), which indicates a eutrophic state of the lake. The values of phytoplankton indices at the studied sites did not differ considerably; the differences resulted more from local conditions such as the contaminant inflow and the macrophyte development than water dynamics.We have demonstrated that in the lake dominated by filamentous Cyanobacteria the ecological status should be determined according to the PMPL index or other indices dependent on the dominant Cyanobacteria species. Since the Q index does not include the functional group S1, the results can lead to the false conclusion that water quality improves with an increased amount of phytoplankton. The high abundance of Cyanobacteria in the lake may have contributed to the poor growth of rotifers.  相似文献   
30.
ABSTRACT

Background: The disruption of circadian rhythm has been found to associate with obesity in vivo and in vitro. Sleep duration, eating habits, total feeding time, and nightshift work can also affect circadian rhythms. This study investigated the association between misalignment of circadian rhythm and obesity in Korean men, using a cross-sectional database.

Methods: This study used data from the Korean National Health and Nutrition Examination Survey (KNHANES), whose study population was 3,658 men aged 18 to 60 years. General and abdominal obesity was defined as a body mass index (BMI) ≥ 25 kg/m2 and waist circumference ≥ 90 cm, respectively. Circadian rhythm factors were determined with a self-report questionnaire and included breakfast frequency, sleep duration, and work time. Frequency of breakfast was divided into regular breakfast (five to seven times a week) and irregular breakfast (less than five times a week). Sleep duration was divided into less than 7 hours, 7–9 hours, and over 9 hours. Working time was defined as day/evening, night shift, and other type. The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for general and abdominal obesity were calculated using multivariable logistic regression according to the number of factors that disturb the circadian rhythm.

Results: Participants with 1 (aOR 1.34, 95% Cl 1.10–1.61) and ≥2 (aOR 1.62, 95% Cl 1.29–2.05) factors disturbing circadian rhythms were associated with elevated risk for general obesity. Similarly, those with 1 (aOR 1.33, 95% Cl 1.09–1.63) and ≥2 (aOR 1.70, 95% Cl 1.32–2.20) factors had elevated risk for abdominal obesity.

Conclusions: Factors disturbing the circadian rhythm were associated with general and abdominal obesity. Additional studies are needed, and associations with metabolic diseases should be investigated.  相似文献   
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