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201.
The aim of the study was to assess the long-term effects of electromagnetic radiation (EMR) on cardiovascular system of medical
staff in physiotherapy. A number of 52 exposed subjects (4 male and 48 female; aged 47.3 ± 8.7 years), and a control group
of 52 subjects, matched by sex and age, with similar job characteristics without EMR exposure were studied. The EMR exposure
from devices emitting at 50 Hz, 150 kHz, 27.12 MHz, 2.45 GHz, and optical radiation was assessed. The relative values of EMR
for the whole frequency range in each physiotherapy were calculated and the obtained quota was much larger than 1. The workload
and psychosocial factors were evaluated, too. The cardiovascular risk factors arterial pressure, lipid profile, body mass
index, waist/hip ratio, smoking, alcohol consumption, nutrition, family history of cardiovascular disease were studied. The
incidence of hypertension was moderate with the studied physiotherapists (26.9% v.s. 23.8% control group). The total cholesterol
(TC) and low-density lipoprotein cholesterol (LDL-C) were significantly higher in the exposed group. The odds ratios indicate
higher possibility of becoming dyslipidemic for the exposed to EMR subjects [for TC OR (95% CI) = 1.570 (1.048–2.351) and
for LDL-C OR (95% CI) = 1.840 (1.158–2.924)]. In conclusion, our data show that the EMR exposure of the medical staff in physiotherapy
could be associated with the adverse effects on cardiovascular system. 相似文献
202.
Glyphosate (N-phosphonomethyl glycine) is the most used herbicide worldwide. The degradation of 14C-labeled glyphosate was
studied under controlled laboratory conditions in three di erent agricultural soils: a silt clay loam, a clay loam and a sandy loam soil.
The kinetic and intensity of glyphosate degradation varied considerably over time within the same soil and among di erent types of
soil. Our results demonstrated that the mineralization rate of glyphosate was high at the beginning of incubation and then decreased
with time until the end of the experiment. The same kinetic was observed for the water extractable residues. The degradation of
glyphosate was rapid in the soil with low adsorption capacity (clay loam soil) with a short half-life of 4 days. However, the persistence
of glyphosate in high adsorption capacity soils increased, with half-live of 19 days for silt clay loam soil and 14.5 days for sandy
loam soil. HPLC analyses showed that the main metabolite of glyphosate, aminomethylphosphonic acid (AMPA) was detected after
three days of incubation in the extracts of all three soils. Our results suggested that the possibility of contamination of groundwater by
glyphosate was high on a long-term period in soils with high adsorption capacity and low degrading activities and/or acid similar to
sandy loam soil. This risk might be faster but less sustainable in soil with low adsorption capacity and high degrading activity like the
clay loam soil. However, the release of non-extractable residues may increase the risk of contamination of groundwater regardless of
the type of soil. 相似文献
203.
204.
Fureix C Hausberger M Seneque E Morisset S Baylac M Cornette R Biquand V Deleporte P 《Die Naturwissenschaften》2011,98(7):583-592
Describing postures has always been a central concern when studying behaviour. However, attempts to compare postures objectively
at phylogenetical, populational, inter- or intra-individual levels generally either rely upon a few key elements or remain
highly subjective. Here, we propose a novel approach, based on well-established geometric morphometrics, to describe and to
analyse postures globally (i.e. considering the animal’s body posture in its entirety rather than focusing only on a few salient
elements, such as head or tail position). Geometric morphometrics is concerned with describing and comparing variation and
changes in the form (size and shape) of organisms using the coordinates of a series of homologous landmarks (i.e. positioned
in relation to skeletal or muscular cues that are the same for different species for every variety of form and function and
that have derived from a common ancestor, i.e. they have a common evolutionary ancestry, e.g. neck, wings, flipper/hand).
We applied this approach to horses, using global postures (1) to characterise behaviours that correspond to different arousal
levels, (2) to test potential impact of environmental changes on postures. Our application of geometric morphometrics to horse
postures showed that this method can be used to characterise behavioural categories, to evaluate the impact of environmental
factors (here human actions) and to compare individuals and groups. Beyond its application to horses, this promising approach
could be applied to all questions involving the analysis of postures (evolution of displays, expression of emotions, stress
and welfare, behavioural repertoires…) and could lead to a whole new line of research. 相似文献
205.
Daniel J. A. Johansson Paul L. Lucas Matthias Weitzel Erik O. Ahlgren A. B Bazaz Wenying Chen Michel G. J. den Elzen Joydeep Ghosh Maria Grahn Qiao-Mei Liang Sonja Peterson Basanta K. Pradhan Bas J. van Ruijven P. R. Shukla Detlef P. van Vuuren Yi-Ming Wei 《Mitigation and Adaptation Strategies for Global Change》2015,20(8):1335-1359
206.
Effects of Landscape Disturbance on Animal Communities in Lake Tanganyika, East Africa 总被引:1,自引:0,他引:1
207.
Many marine organisms are fixed or highly sedentary as adults but the adult population may be strongly dependent on the oceanic transport of planktonic larvae. In order to assess interactions between oceanographic and biological processes that determine the population dynamics of marine organisms with a sessile adult phase restricted to the coastline and a planktonic larval phase, we present a stage-structured finite element model for the barnacle Balanus glandula that inhabits the rocky intertidal zone of central California, USA. 相似文献
208.
The aim of this paper is to tackle the problem that arises from asymmetrical data cubes formed by two crossed factors fixed by the experimenter (factor A and factor B, e.g., sites and dates) and a factor which is not controlled for (the species). The entries of this cube are densities in species. We approach this kind of data by the comparison of patterns, that is to say by analyzing first the effect of factor B on the species-factor A pattern, and second the effect of factor A on the species-factor B pattern. The analysis of patterns instead of individual responses requires a correspondence analysis. We use a method we call Foucart's correspondence analysis to coordinate the correspondence analyses of several independent matrices of species x factor A (respectively B) type, corresponding to each modality of factor B (respectively A). Such coordination makes it possible to evaluate the effect of factor B (respectively A) on the species-factor A (respectively B) pattern. The results obtained by such a procedure are much more insightful than those resulting from a classical single correspondence analysis applied to the global matrix that is obtained by simply unrolling the data cube, juxtaposing for example the individual species x factor A matrices through modalities of factor B. This is because a single global correspondence analysis combines three effects of factors in a way that cannot be determined from factorial maps (factor A, factor B, and factor A x factor B interaction) whereas the applications of Foucart's correspondence analysis clearly discriminate two different issues. Using two data sets, we illustrate that this technique proves to be particularly powerful in the analyses of ecological convergence which include several distinct data sets and in the analyses of spatiotemporal variations of species distributions. 相似文献
209.
Michel De Lara 《Environmental Modeling and Assessment》2018,23(6):703-712
Resilience is a rehashed concept in natural hazard management—resilience of cities to earthquakes, to floods, to fire, etc. In a word, a system is said to be resilient if there exists a strategy that can drive the system state back to “normal” after any perturbation. What formal flesh can we put on such a malleable notion? We propose to frame the concept of resilience in the mathematical garbs of control theory under uncertainty. Our setting covers dynamical systems both in discrete or continuous time, deterministic or subject to uncertainties. We will say that a system state is resilient if there exists an adaptive strategy such that the generated state and control paths, contingent on uncertainties, lay within an acceptable domain of random processes, called recovery regimes. We point out how such recovery regimes can be delineated thanks to so-called risk measures, making the connection with resilience indicators. Our definition of resilience extends others, be they “à la Holling” or rooted in viability theory. Indeed, our definition of resilience is a form of controllability for whole random processes (regimes), whereas others require that the state values must belong to an acceptable subset of the state set. 相似文献
210.
Pierre-André Jouvet Philippe Michel Gilles Rotillon 《Environmental Modeling and Assessment》2010,15(1):1-11
We are interested in the impact of pollution permits on wages and profits. We analyze important consequences of introducing
a market of pollution permits. A fundamental issue concerns the initial allocation of such permits: should they be allocated
freely by grandfathering or be auctioned. The international symmetric case allows us to capture the essence of the problem
on income factor. We show that allocating permits to factors in proportion of their contribution to production leads to an
efficient (neoclassical) distribution. Considering the international asymmetric case, we show that a permit market does not
modify the competitive world equilibrium without permits when the total allocation is large enough. When it is not, if allocation
of permits is not proportional to the emissions in the world without permits, there is a reduction factor of emissions that
results from the equilibrium allocation of capital. 相似文献