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71.
Although a number of manufactured nanoparticles are applied for the medical and clinical purposes, the understanding of interaction between nanomaterials and biological systems are still insufficient. Using nematode Caenorhabditis elegans model organism, we here investigated the in vivo toxicity or safety of hydroxylated fullerene nanoparticles known to detoxify anti-cancer drug-induced oxidative damages in mammals. The survival ratio of C. elegans rapidly decreased by the uptake of nanoparticles from their L4 larval stage with resulting in shortened lifespan (20 d). Both reproduction rate and body size of C. elegans were also reduced after exposure to 100 μg mL−1 of fullerol. We found ectopic cell corpses caused by apoptotic cell death in the adult worms grown with fullerol nanoparticles. By the mutation of core pro-apoptotic regulator genes, ced-3 and ced-4, these nanoparticle-induced cell death were significantly suppressed, and the viability of animals consequently increased despite of nanoparticle uptake. The apoptosis-mediated toxicity of nanoparticles particularly led to the disorder of digestion system in the animals containing a large number of undigested foods in their intestine. These results demonstrated that the water-soluble fullerol nanoparticles widely used in medicinal applications have a potential for inducing apoptotic cell death in multicellular organisms despite of their antioxidative detoxifying property.  相似文献   
72.

Introduction  

Acidic and metal(oid)-rich topsoils resulted after 34 years of continuous operations of a copper smelter in the Puchuncaví valley, central Chile. Currently, large-scale remediation actions for simultaneous in situ immobilization of metals and As are needed to reduce environmental risks of polluted soils. Aided phytostabilization is a cost-effective alternative, but adequate local available soil amendments have to be identified and management options have to be defined.  相似文献   
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74.
In the present study, the antimicrobial and antiradical activities of 15 essential oils were investigated. The antimicrobial activities were determined by using agar disc diffusion and broth microdilution methods against Clostridium genus and antioxidant properties of essential oils by testing their scavenging effect on DPPH radicals activities. We determined the antibacterial activity of Clostridium butyricum, Clostridium hystoliticum, Clostridium intestinale, Clostridium perfringens and Clostridium ramosum. We obtained the original commercial essential oils samples of Lavandula angustifolia, Carum carvi, Pinus montana, Mentha piperita, Foeniculum vulgare Mill., Pinus sylvestris, Satureia montana, Origanum vulgare L. (2 samples), Pimpinella anisum, Rosmarinus officinalis L., Salvia officinalis L., Abies alba Mill., Chamomilla recutita L. Rausch and Thymus vulgaris L. produced in Slovakia (Calendula a.s., Nova Lubovna, Slovakia). The results of the disk diffusion method showed very high essential oils activity against all tested strains of microorganisms. The best antimicrobial activity against C. butyricum was found at Pimpinella anisum, against C. hystoliticum was found at Pinus sylvestris, against C. intestinale was found at Satureia hortensis L., against C. perfringens was found at Origanum vulgare L. and against C. ramosum was found at Pinus sylvestris. The results of broth microdilution assay showed that none of the essential oils was active against C. hystoliticum. The best antimicrobial activity against C. butyricum was found at Abies alba Mill., against C. intestinale was found at Abies alba Mill., against C. perfringens was found at Satureia montana and against C. ramosum was found at Abius alba and Carum carvi. Antioxidant DPPH radical scavenging activity was determined at several solutions of oil samples (50 μL.mL?1–0.39 μL.mL?1) and the best scavenging effect for the highest concentration (50 μL.mL?1) was observed. The antioxidant properties were different in particular plant species. The highest% of inhibition after 30 min. of reaction was observed at Origanum vulgare (93%), Satureia montana (90.66%) and Lavandula augustifolia (90.22%).  相似文献   
75.
The beneficial effect of a TiO2-based photocatalytic treatment on the indoor air purification of a swine farm has been evaluated in a trial performed in two identical mechanically ventilated traditional weaning units, with 391 animals lodged in each of them. One unit was used as reference, whereas the walls of the second unit (260 m2) were coated with ca. 70 g m(-2) of TiO2 and irradiated with ten UV-A lamps. The environmental parameters (i.e. the ventilation rate, the internal and external temperature and relative humidity), together with NH3, CH4, CO2 and N2O concentrations in the exhaust ducts and PM10 emissions, were monitored in the two units throughout all of the production cycle (75 days). Significant decreases in CH4 concentration (ca. 27%, P < 0.05) and PM10 emission (ca. 17%, P < 0.01) were observed, together with an increase of the piglets' productive performance in the treated unit with respect to the reference one. Indeed, the ADG (Average Daily Gain of piglets) was 424 g vs. 414 g for the piglets lodged in the two units, respectively, with a significantly better feed conversion ratio (FCR, ratio between the food ingested by the animals and their weight gain) of 2.18 vs. 2.44 (P < 0.001). Therefore, the photocatalytic treatment with TiO2 coating had positive effects not only on methane concentration and particulate matter concentration and emission, but also significantly improved the feed conversion ratio of growing piglets, very likely due to the increased quality of indoor air, with positive economic repercussions for the farmer. Internal photocatalytic treatment in swine husbandry could thus be considered as a potential Best Available Technology (BAT).  相似文献   
76.
In modern intensive agriculture, plastics are used in several applications (i.e. mulch films, drip irrigation tubes, string, clips, pots, etc.). Interest towards applying biodegradable plastics to replace the conventional plastics is promising. Ten monomers, which can be applied in the synthesis of potentially biodegradable polyesters, were tested according to ASTM 5988-96 (standard respirometric test to evaluate aerobic biodegradation in soil by measuring the carbon dioxide evolution): adipic acid, azelaic acid, 1,4-butanediol, 1,2-ethanediol, 1,6-hexanediol, lactic acid, glucose, sebacic acid, succinic acid and terephthalic acid. Eight replicates were carried out for each monomer for 27-45 days. The numerical code AQUASIM was applied to process the CO? experimental data in order to estimate values for the parameters describing the different mechanisms occurring to the monomers in soil: i) the first order solubilization kinetic constant, K(sol) (d?1); ii) the first order biodegradation kinetic constant, K(b) (d?1); iii) the lag time in biodegradation, t(lag) (d); and iv) the carbon fraction biodegraded but not transformed into CO?, Y (-). The following range of values were obtained: [0.006 d?1, 6.9 d?1] for K(sol), [0.1 d?1, 1.2 d?1] for K(b), and [0.32-0.58] for Y; t(lag) was observed for azelaic acid, 1,2-ethanediol, and terephthalic acid, with estimated values between 3.0 e 4.9 d.  相似文献   
77.
Barriers and bridges to implement policies about sustainable development and sustainability commonly depend on the past development of social–ecological systems. Production of metals required integration of use of ore, streams for energy, and wood for bioenergy and construction, as well as of multiple societal actors. Focusing on the Swedish Bergslagen region as a case study we (1) describe the phases of natural resource use triggered by metallurgy, (2) the location and spatial extent of 22 definitions of Bergslagen divided into four zones as a proxy of cumulative pressure on landscapes, and (3) analyze the consequences for natural capital and society. We found clear gradients in industrial activity, stream alteration, and amount of natural forest from the core to the periphery of Bergslagen. Additionally, the legacy of top-down governance is linked to today’s poorly diversified business sector and thus municipal vulnerability. Comparing the Bergslagen case study with other similar regions in Russia and Germany, we discuss the usefulness of multiple case studies.  相似文献   
78.
79.

Silicon-based fertilizers and soil amendments can have direct and indirect positive influences on cultivated plants. The solid forms of Si-based substances, the most widespread in use, are efficient only at high application rates due to their low level of solubility. Several types of Si-based substances such as fumed silica, slags from the iron and steel industry, modified slags, and a Si-rich product were tested using barley and pea as silicon accumulative and non-accumulative plants, respectively, at two application rates. The plants were grown under toxic concentrations of heavy metals in a greenhouse. Si-rich materials high in water-soluble Si had a positive effect at both the low and high application rates, and for both plant species. This type of substance can be regarded as Si fertilizer, demonstrating greater efficiency at a low application rate and lessened efficiency at a high application rate for protection of the cultivated plants against accumulation of the heavy metals.

  相似文献   
80.
Little research has been conducted on the occurrence of pharmaceuticals and personal care products (PPCPs) in the marine environment despite being increasingly impacted by these contaminants. This article reviews data on the occurrence of PPCPs in seawater, sediment, and organisms in the marine environment. Data pertaining to 196 pharmaceuticals and 37 personal care products reported from more than 50 marine sites are analyzed while taking sampling strategies and analytical methods into account. Particular attention is focused on the most frequently detected substances at highest concentrations. A snapshot of the most impacted marine sites is provided by comparing the highest concentrations reported for quantified substances. The present review reveals that: (i) PPCPs are widespread in seawater, particularly at sites impacted by anthropogenic activities, and (ii) the most frequently investigated and detected molecules in seawater and sediments are antibiotics, such as erythromycin. Moreover, this review points out other PPCPs of concern, such as ultraviolet filters, and underlines the scarcity of data on those substances despite recent evidence on their occurrence in marine organisms. The exposure of marine organisms in regard to these insufficient data is discussed.  相似文献   
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