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801.
802.
The Science of Nature - The geophilomorph centipede, Himantarium gabrielis, when disturbed, discharges a viscous and proteinaceous secretion from the sternal glands. This exudate was found by gas...  相似文献   
803.
Carbon labels inform consumers about the amount of greenhouse gases (GHGs) released during the production and consumption of goods, including food. In the future consumer and legislative responses to carbon labels may favour goods with lower emissions, and thereby change established supply chains. This may have unintended consequences.We present the carbon footprint of three horticultural goods of different origins supplied to the United Kingdom market: lettuce, broccoli and green beans. Analysis of these footprints enables the characterisation of three different classes of vulnerability which are related to: transport, national economy and supply chain specifics.There is no simple relationship between the characteristics of an exporting country and its vulnerability to the introduction of a carbon label. Geographically distant developing countries with a high level of substitutable exports to the UK are most vulnerable. However, many developing countries have low vulnerability as their main exports are tropical crops which would be hard to substitute with local produce.In the short term it is unlikely that consumers will respond to carbon labels in such a way that will have major impacts in the horticultural sector. Labels which require contractual reductions in GHG emissions may have greater impacts in the short term.  相似文献   
804.
Application of municipal solid waste (MSW) to arable land can be used to close the nutrient cycle between urban and rural areas. The aim of the current study was to quantify net N mineralization and respiration from composted MSW (CMSW) and anaerobically digested MSW (ADMSW) applied to soil, and to test whether a simple relationship between net N mineralization and respiration that was developed for plant materials, was applicable for these types of MSW. In a laboratory experiment, CMSW and ADMSW were incorporated into soil and incubated at 15 degrees C. During the 149-day experiment, netN mineralization and respiration were determined. Cumulative respiration derived from both MSW types was very steep during the first 30 days, after which it levelled off. However, calculated on the basis of applied C, the ADMSW was 10 times more degradable than the CMSW. Both MSW types caused initial net N immobilization followed by re-mineralization. A simple model based on the relationship between net N mineralization and respiration was only applicable for the MSW after significant modifications. If farmers are to recognize CMSW and ADMSW as valuable fertilizers, it is important that they can be produced with higher maturity, in order to avoid initial N immobilization.  相似文献   
805.
Our behaviour towards the environment depends on our beliefs about the environment. Beliefs, however, are a subject of change, particularly during important life transitions such as the transition to adolescence, because this is a period when an individual develops the ability of complex and abstract reasoning. Understanding this transition is therefore crucial for understanding and predicting the attitudes and courses of action in terms of sustainable development later in life. Due to many methodological constraints, the number of empirical studies examining these issues is very limited; the current study aimed to collect empirical data to explore the origins of our beliefs about the environment-related issues. We devised a picture association test and used it to compare children’s and adolescents’ beliefs about our environment in the context of the means of transportation. A large sample of 2264 participants aged 6–18 years took part in the study. The data supported the claim that children’s beliefs about environment share egocentric properties. The findings represent an important puzzle into the whole picture of children’s thinking and offer us great insight into the origins of beliefs about environment-related questions in adults. Educational implications are addressed.  相似文献   
806.
The study evaluates chromosome damage caused by simultaneous occupational exposure to ethylene oxide (EtO) and formaldehyde (FA). To determine the extent of chromosome damage, eleven workers were analyzed using chromosome aberration (CA) assay, sister chromatid exchange (SCE) frequencies, micronucleus (MN) assay, and mitotic activity (MA). The results show significant deviations in subjects exposed to EtO and FA from control values in all four assays. The study shows a complex mode of action of EtO and FA on human genome and confirms the need for further research of cytogenetic risk which should be obtained through several assays.  相似文献   
807.
In a number of countries across the world, aluminium in the form of polyaluminium chloride has been used in the treatment of freshwaters for the direct removal of cyanobacteria, or phosphorus removal, but knowledge about its effect on zooplankton species is poor. In our study, polyaluminium chloride toxicity was tested on both artificial and natural freshwaters for a better understanding and prediction of effects in real ecosystems. Our results indicate that prediction of effects in a real ecosystem based on standard ISO methods is insufficient, and tests with nontarget species (including invertebrates) should be done before each treatment using the water samples from the treated location. Effective concentrations of polyaluminium chloride can differ markedly according to the type of water composition used in the assay. Our experiments proved that EC50 values can fluctuate between 9.89 and 54.29 mg·L?1 of Al3+, and the toxicity is dominantly dependent on the treated water conductivity. This parameter seems to be the dominant source of different effects on zooplankton species after treatment and thus should be properly tested before each use of polyaluminium chloride as a treatment compound.  相似文献   
808.
In this study, we analysed pellets from long-eared owls (Asio otus) collected from four localities in Belgrade (Serbia). The pellets contained the remains of prey, namely voles (Arvicola terrestris) and field mice (Apodemus agrarius). The concentrations of 14 elements (Ca, P, Mg, Na, K, Fe, Zn, Sr, Ba, Mn, Ti, Cu, Si, B) were evaluated in whole pellets and in samples containing only bone tissue, which were dissected from the whole pellet. The increased levels of certain elements, including Mn, Zn, Ba, Cu and radioactive 40K, indicate contamination of the soil by various sources, such as industrial plants and agricultural practices. From the results presented in this article, we suggest that the analysis of owl pellets may indicate the quality of the local environment.  相似文献   
809.

The biodegradation of 2‐halosubstituted and 4‐halosubstituted benzyl alcohols was studied using two sources of biodegrative micro‐organisms: mixed culture from the ?TUDA waste water treatment plant, Dom?ale, and the white rot fungus Phanerochaete chrysosporium strain MZKI B‐223 (ATCC 24725). The results obtained by this study indicate the interrelationship between the types of micro‐organism used in the experiments and the type and position of the halogen element on the aromatic ring.  相似文献   
810.
Ontogenetic changes in antipredator behavior optimize survival of growing animals. Leopard geckos (Eublepharis macularius) respond to a simulated predator either by postural and vocal threats, sometimes followed by biting, or alternatively by a rapid escape. The former “confrontational” and the latter “avoidance” behavior rarely occurs in a sequence; in fact, they represent mutually exclusive defensive strategies. We examined 552 individuals of a leopard gecko (E. macularius) of various ages, from hatching up to adulthood (31 months). Each experimental animal was exposed to a sequence of five “water-spraying” and ten “stick” (stick poking on base of the tail) stimuli, and the emitted behavior was recorded. We analyzed the effects of age, body size, body condition, adult–juvenile coloration, and sex on observed behavioral traits. The results showed that in the case of water-spraying stimulus, the usage of deterrent vocalization or escape tactic was affected by age and condition. In addition to that, using deterrent vocalization was influenced by the coloration of the animal. Stick stimulus evokes antipredator strategies that correspond with age and coloration (deterrent vocalization) and also with standardized body size (escape). Thus, leopard geckos exhibit clear ontogenetic change of defensive strategies, from threat–vocalization–bite strategy prevailing in juveniles to an escape strategy typical for adults. This behavioral change is accompanied by the ontogenetic switch of coloration from presumably warning contrasting light–dark banded pattern of juveniles to a cryptic spotted coloration of the adults.  相似文献   
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