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171.
Many colourful sexually selected signals in animals are carotenoid-dependent and, because carotenoids function as antiradicals and immunostimulating molecules, carotenoid-dependent signals may honestly reflect the health state of individuals. Some others nutrients like vitamin A may also enhance health and colouration, but these have rarely been tested alongside carotenoids in colourful birds. Here, we examined whether beak colour of the spotless starling (Sturnus unicolor) reflected circulating levels of carotenoids and/or vitamin A (retinol). Spotless starlings are polygynous, sexually dimorphic birds (i.e. length of chest feathers). The tip of the beaks of male and female spotless starlings is more intensely coloured at the beginning of the breeding season and becomes dull after mating, which may suggest a sexual function. We found that females have a more intensely coloured beak and higher plasma carotenoid concentration than males during mating, and, despite the finding that carotenoid and vitamin A levels were not significantly related; colour intensity was positively correlated with plasma concentration of carotenoids and vitamin A in both sexes. However, adult beak coloration was not associated with carotenoid and vitamin A concentrations after nestlings were hatched. Therefore, beak colouration of spotless starlings provides information about circulating levels of carotenoids and vitamins during the mating season and may potentially function as a reliable signal of physiological status in the context of sexual selection.  相似文献   
172.
The formation of aromatic amines was investigated using a summarized test (NEDA-test) during the composting of 2,4,6-trinitrotoluene (TNT) contaminated soil. In this test, the aromatic amines were diazolated and then coupled to N-1-Naphthyl-ethylenediamine-dihydrochloride (NEDA) to yield an azo dye which can be monitored photometrically. The test was calibrated for known TNT-metabolites with an active amine-group. Liquid samples from composting- and liquid-culture-experiments were analyzed by HPLC for these known metabolites. Moreover, the samples were monitored by the NEDA-test and the expected extinction of the TNT-metabolites found with amine function were extrapolated with the help of calibration curves. It was shown that substantial differences are obvious between the monitored and extrapolated values. After separation into polar and non-polar aromatic amines, it became clear that these differences are made by the polar aromatic amines. Polar aromatic amines, which are not detectable by presently available analytical tests, were generated during the composting of TNT-contaminated soils. Contaminated stagnant water, which was generated during anaerobization of a compost prephase, was treated aerobically for 70 days in a biofermenter. During this treatment TNT and its known metabolites were eliminated almost entirely. Simultaneously, the toxicity in the Lumis Tox-test decreased drastically. In striking contrast, the sum of aromatic amines decreased only to a minor extent. Moreover, the percentage of polar compounds from total amount of aromatic amines increased drastically from 48% to more than 95%. At present, the chemical identification of these polar compounds is still missing and is the object for further research.  相似文献   
173.
Brominated flame retardants (BFRs) are widely used industrial chemicals, residues of which can be nowadays found in all environmental compartments. The widespread presence of BFRs in various environmental compartments and food chain is a consequence of both their broad application area and physico-chemical properties, such as resistance to degradation and high lipophilicity. Alike in the case of other halogenated persistent organic pollutants (POPs), fish can be used as a bioindicator of aquatic environment pollution. In presented study, conducted in the year 2005, altogether 80 samples representing the most abundant fresh water fish species, viz. chub (Leuciscus cephalus), bream (Abramis brama), and perch (Perca fluviatilis) collected in 11 sampling sites located at Elbe and Vltava (Moldau) rivers were examined for levels of major BFRs. Without any exception, BFRs were detected in all fish samples. BDE 47 was the dominating congener in all fish species. This fact was not surprising, since it used to be the main component in various kinds of technical mixtures. With regard to relatively high levels of BDE 47 in fish tissue, as compared to other BFRs, and considering strong correlation with the total PBDEs content, simplified laboratory examination and, consequently, increased samples throughput can be obtained when only this congener is monitored. The potential of comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC-TOFMS), to provide more comprehensive information on the bioaccumulating chemicals occurring in fish samples, has been demonstrated in this study.  相似文献   
174.
Lindane (??-hexachlorocyclohexane, ??-HCH) is a recalcitrant and toxic organochlorine insecticide. Due to its non-selective production process and widespread use, HCH isomers and their degradation products have been detected frequently in soils and groundwater. An innovative technology using microbial produced Pd(0) nanoparticles, i.e. bio-Pd, was developed to treat groundwater containing a mixture of HCHs and chlorobenzenes. In a first step, the groundwater was de-ironized and most of the chlorobenzenes were removed in a biological trickling filter. The ??g?L?1 levels of HCHs and chlorobenzenes were removed in a second step by the bio-Pd-based technology. Therefore, a 200-L pilot scale reactor was developed with 100?mg?L?1 bio-Pd encapsulated in alginate beads. Hydrogen gas was bubbled at the bottom of the reactor and served to charge the bio-Pd catalyst. The reactor influent contained 5.2???g?L?1 HCHs and 51.1???g?L?1 chlorobenzenes. During a test period of 10?days, 29% of the HCH isomers and 63% of the chlorobenzenes were removed applying a nominal hydraulic residence time of 4?h. These removal percentages could be increased to 75 and 68% by doubling the nominal hydraulic residence time to 8?h. This study demonstrated that biologically produced nanoparticles of Pd can be applied for the large-scale remediation of groundwater contaminated with HCHs.  相似文献   
175.
Polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) were monitored over 56 days in calcareous contaminated-soil amended with either or both biochar and Eisenia fetida. Biochar reduced total (449 to 306 mg kg−1) and bioavailable (cyclodextrin extractable) (276 to 182 mg kg−1) PAHs, PAH concentrations in E. fetida (up to 45%) but also earthworm weight. Earthworms increased PAH bioavailability by >40%. Combined treatment results were similar to the biochar-only treatment. Earthworms increased water soluble Co (3.4 to 29.2 mg kg−1), Cu (60.0 to 120.1 mg kg−1) and Ni (31.7 to 83.0 mg kg−1) but not As, Cd, Pb or Zn; biochar reduced water soluble Cu (60 to 37 mg kg−1). Combined treatment results were similar to the biochar-only treatment but gave a greater reduction in As and Cd mobility. Biochar has contaminated land remediation potential, but its long-term impact on contaminants and soil biota needs to be assessed.  相似文献   
176.
On the face of it, the 1990s have marked the transformation of the UK's waste management policy. A commitment to waste minimisation and recycling, within the terms of the internationally accepted waste hierarchy, have replaced an almost complacent defence of landfill. However, aside from the dramatic transformation of the vocabulary, the reality of local authority waste disposal has, with a few notable exceptions, been characterised more by continuity than revolution. This article suggests that the modesty of local authority recycling is best explained through an appreciation of what can be described as recycling practice. Recycling in the UK has taken a distinctive form comprising: environmentalism, entrepreneurialism and policy advocacy. The components of this practice explain both the successes and failures of local authority recycling. Despite its oppositional roots, the Conservative Government found 'recycling practice' conducive to their reliance upon a mix of aspirational targets and market-based instruments (MBIs). Advice circulated as guidance to local authorities emphasised viability as the principal criterion of scheme assessment and in such a way sustained the limited scale and ambitions of recycling practice.  相似文献   
177.

Objective

To investigate whether perioperative fetal hemodynamic changes in twin-to-twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years.

Methods

Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008-2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley-III cognitive/motor developmental test-score > 2SD below the mean.

Results

Long-term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA-PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17-21.05, P = .03), a change from normal umbilical artery pulsatility index (UA-PI) presurgery to UA-PI >p95 postsurgery (OR 4.19; 95% CI: 1.04-16.87, P = .04), a change from normal to MCA-PSV >1.5MoM (OR 4.75; 95% CI: 1.43-15.77, P = .01).

Conclusion

Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome.  相似文献   
178.

Objective

We performed a 1-year evaluation of a novel strategy of simultaneously analyzing single nucleotide variants (SNVs), copy number variants (CNVs) and copy-number-neutral Absence-of-Heterozygosity from Whole Exome Sequencing (WES) data for prenatal diagnosis of fetuses with ultrasound (US) anomalies and a non-causative QF-PCR result.

Methods

After invasive diagnostics, whole exome parent-offspring trio-sequencing with exome-wide CNV analysis was performed in pregnancies with fetal US anomalies and a non-causative QF-PCR result (WES-CNV). On request, additional SNV-analysis, restricted to (the) requested gene panel(s) only (with the option of whole exome SNV-analysis afterward) was performed simultaneously (WES-CNV/SNV) or as rapid SNV-re-analysis, following a normal CNV analysis.

Results

In total, 415 prenatal samples were included. Following a non-causative QF-PCR result, WES-CNV analysis was initially requested for 74.3% of the chorionic villus (CV) samples and 45% of the amniotic fluid (AF) samples. In case WES-CNV analysis did not reveal a causative aberration, SNV-re-analysis was requested in 41.7% of the CV samples and 17.5% of the AF samples. All initial analyses could be finished within 2 weeks after sampling. For SNV-re-analysis during pregnancy, turn-around-times (TATs) varied between one and 8 days.

Conclusion

We show a highly efficient all-in-one WES-based strategy, with short TATs, and the option of rapid SNV-re-analysis after a normal CNV result.  相似文献   
179.
A new method for the determination of submicromolar and nanomolar concentrations of herbicide Bifenox using differential pulse voltammetry at a mercury meniscus modified silver solid amalgam electrode is described. This new type of working electrode is non-toxic, environmentally friendly, and compatible with principles of green analytical chemistry, and its surface can be easily electrochemically renewed in the case of passivation. The newly developed direct differential pulse voltammetric determination of Bifenox gives limit of determination 6.7·10?7 and 6.9·10?7?M in drinking and river water, respectively. Both the selectivity and the sensitivity can be further increased by preliminary separation and preconcentration using solid phase extraction. This combination enables to reach limit of determination 0.9?×?10?9 and 1.5?×?10?9?M for drinking and river water, respectively. Because of lower running and investment costs, this electroanalytical method can be used for large scale monitoring of possible water contamination with tested herbicide.  相似文献   
180.
The fisher (Martes pennanti) is a forest-dwelling carnivore whose current distribution and association with late-seral forest conditions make it vulnerable to stand-altering human activities or natural disturbances. Fishers select a variety of structures for daily resting bouts. These habitat elements, together with foraging and reproductive (denning) habitat, constitute the habitat requirements of fishers. We develop a model capable of predicting the suitability of fisher resting habitat using standard forest vegetation inventory data. The inventory data were derived from Forest Inventory and Analysis (FIA), a nationwide probability-based sample used to estimate forest characteristics. We developed the model by comparing vegetation and topographic data at 75 randomly selected fisher resting structures in the southern Sierra Nevada with 232 forest inventory plots. We collected vegetation data at fisher resting locations using the FIA vegetation sampling protocol and centering the 1-ha FIA plot on the resting structure. To distinguish used and available inventory plots, we used nonparametric logistic regression to evaluate a set of a priori biological models. The top model represented a dominant portion of the Akaike weights (0.87), explained 31.5% of the deviance, and included the following variables: average canopy closure, basal area of trees <51 cm diameter breast height (dbh), average hardwood dbh, maximum tree dbh, percentage slope, and the dbh of the largest conifer snag. Our use of routinely collected forest inventory data allows the assessment and monitoring of change in fisher resting habitat suitability over large regions with no additional sampling effort. Although models were constrained to include only variables available from the list of those measured using the FIA protocol, we did not find this to be a shortcoming. The model makes it possible to compare average resting habitat suitability values before and after forest management treatments, among administrative units, across regions and over time. Considering hundreds of plot estimates as a sample of habitat conditions over large spatial scales can bring a broad perspective, at high resolution, and efficiency to the assessment and monitoring of wildlife habitat.  相似文献   
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