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281.
Recent crises in regions where exclusive breastfeeding is not the norm have highlighted the importance of effective policies and guidelines on infant feeding in emergencies. In 1993, UNICEF compiled a collection of policy and guideline documents relating to the feeding of infants in emergency situations. In June 2000 Save the Children, UK, UNICEF and the Institute of Child Health undertook a review of those documents, updating the list and identifying the common ground that exists among the different policies. The review also analysed the consistency of the policy framework, and highlighted important areas where guidelines are missing or unclear. This article is an attempt to share more widely the main issues arising from this review. The key conclusions were that, in general, there is consensus on what constitutes best practice in infant feeding, however, the lack of clarity in the respective responsibilities of key UN agencies (in particular UNICEF, UNHCR and WFP) over issues relating to co-ordination of activities which affect infant-feeding interventions constrains the implementation of systems to support best practice. Furthermore, the weak evidence base on effective and appropriate intervention strategies for supporting optimal infant feeding in emergencies means that there is poor understanding of the practical tasks needed to support mothers and minimise infant morbidity and mortality. We, therefore, have two key recommendations: first that the operational UN agencies, primarily UNICEF, examine the options for improving co-ordination on a range of activities to uphold best practice of infant feeding in emergencies; second, that urgent attention be given to developing and supporting operational research on the promotion of optimal infant-feeding interventions. 相似文献
282.
Calzoni GL Antognoni F Pari E Fonti P Gnes A Speranza A 《Environmental pollution (Barking, Essex : 1987)》2007,149(2):239-245
The purpose of this work was to evaluate the quality of a rural area near Faenza (Italy) by using an active biomonitoring approach, i.e., by placing homogeneous individuals of the perennial shrub Rosa rugosa in different sites throughout the area. Further sites, within the city or its environs, were used for comparison. Soil and leaves of R. rugosa were analyzed for their heavy metal content. The total heavy metal pattern of leaves closely paralleled the pattern registered in soil, with the highest content (both in total and assimilable forms) at the site in the urban area, which is exposed to heavy traffic. Pollen quality (abortiveness and viability) was also tested as a potential indicator of pollution. Pollen abortiveness was strictly related to Pb levels in leaves, while viability was inversely related to leaf Cr content. Our results suggest that R. rugosa has the potential to be a good biomonitoring system. 相似文献
283.
Giuseppa Grazia Aprile Mina Di Salvatore Giovanna Carratù Antonio Mingo Anna Maria Carafa 《Environmental monitoring and assessment》2010,162(1-4):291-299
We compared the capacity to accumulate airborne heavy metals of two lichens (Flavoparmelia caperata and Parmotrema chinense) and one higher plant (Nerium oleander) at a very densely populated urban site near Naples. After 15, 45, 75, and 120 days of exposure at four sites with different levels of air pollution, equal portions of thalli and 20 leaves were collected, and four environmentally significant elements, Fe, Cu, Zn, and Pb, were measured by inductively coupled plasma analysis. To compare the accumulation rates of lichens and the vascular plant, we determined an index of relative accumulation rate of pollutants during time and the ratio between the concentrations of each element in exposed samples to that of control samples (exposed-to-control ratio). Our data indicate F. caperata as being the most suitable bioaccumulator, followed by P. chinense. N. oleander was also found to be a useful heavy metal biomonitor though not suitable as a bioaccumulator. 相似文献
284.
Corona P Agrimi M Baffetta F Barbati A Chiriacò MV Fattorini L Pompei E Valentini R Mattioli W 《Environmental monitoring and assessment》2012,184(3):1409-1422
Urban areas are continuously expanding today, extending their influence on an increasingly large proportion of woods and trees
located in or nearby urban and urbanizing areas, the so-called urban forests. Although these forests have the potential for
significantly improving the quality the urban environment and the well-being of the urban population, data to quantify the
extent and characteristics of urban forests are still lacking or fragmentary on a large scale. In this regard, an expansion
of the domain of multipurpose forest inventories like National Forest Inventories (NFIs) towards urban forests would be required.
To this end, it would be convenient to exploit the same sampling scheme applied in NFIs to assess the basic features of urban
forests. This paper considers approximately unbiased estimators of abundance and coverage of urban forests, together with
estimators of the corresponding variances, which can be achieved from the first phase of most large-scale forest inventories.
A simulation study is carried out in order to check the performance of the considered estimators under various situations
involving the spatial distribution of the urban forests over the study area. An application is worked out on the data from
the Italian NFI. 相似文献
285.
Pernilla Christensen Anna Hedström Ringvall 《Environmental monitoring and assessment》2013,185(9):7279-7293
The National Inventory of Landscapes in Sweden (NILS) is a large-scale, sample-based monitoring program that combines aerial photointerpretation with field inventory to follow landscape-scale biophysical conditions and changes. A statistical power analysis was conducted before the NILS program began in 2003 with the aim to determine an appropriate sampling effort and compare some design alternatives. The chosen sampling effort was then evaluated in a second power analysis conducted just before the first 5-year re-inventory rotation started. The latter power analysis revealed which magnitude of actual change might be detected within the future for different central monitoring variables. This article reports results from these power analyses and discusses our experiences in using power analysis as a tool for designing large-scale monitoring programs. The results showed that even quite small changes in the more common variables, such as land cover types and more common plant species, can be detected on the national scale. However, on the regional scale, or for less common variables, changes will be more difficult to detect. The power analyses have revealed the size level of changes that will be possible to detect. The results have also generated incentives for further improvements of NILS, e.g., input to the modification and revision of the variable content, flow and hierarchy, and incentives for launching other complementary monitoring programs connected to NILS. They have also created a basis for a better and more user-oriented communication of results from NILS to different stakeholders. 相似文献
286.
Nikolopoulos D Petraki E Marousaki A Potirakis SM Koulouras G Nomicos C Panagiotaras D Stonham J Louizi A 《Journal of environmental monitoring : JEM》2012,14(2):564-578
This paper focuses on the environmental monitoring of radon in soil as a potential trace gas in the search of earthquake precursors. The paper reports the following: (a) Pre-monitoring experiments. (b) Set-up of methods and devices. (c) Active and passive monitoring results concentrating on two extremely-strong radon anomalies (~ 500 kBq m(-3)). (e) Discussion regarding the employed ± 2σ technique for identifying radon disturbances. (f) Application of wavelet-power-spectrum fractal analysis for detecting power-law behaviour. The strong anomalies exhibited anti-persistent power-law-beta-values (b = (1.8 ± 0.2), b = (1.8 ± 0.3)) significantly higher than those of the baseline. Persistent b-values were also detected. The findings comply with a self-organised-critical pre-earthquake state. (h) Discussion on models that interpret the radon anomalies focusing on the recently-proposed asperity-model. (i) Application of a recent technique which showed that the two strong disturbances were proportional to the strain change. It was concluded that the strong radon disturbances may be linked to the strong earthquake of 8/6/2008, M = 6.5, occurred 29 km away from the installed instrumentation. 相似文献
287.
Monitoring pollution in River Mureş, Romania, part II: metal accumulation and histopathology in fish
Triebskorn R Telcean I Casper H Farkas A Sandu C Stan G Colărescu O Dori T Köhler HR 《Environmental monitoring and assessment》2008,141(1-3):177-188
As a part of an exposure and effect monitoring conducted along the river Mureş, Western Romania in 2004, the health status
of two indigenous fish species, sneep (Chondrostoma nasus) and European chub (Leuciscus cephalus) was investigated upstream and downstream the city of Arad. In fish, histopathology was assessed in liver and gills, and
heavy metals (cadmium, copper, lead and zinc) were analyzed in liver samples. In both fish species, histopathological reactions
in the gills (epithelial lifting, focal proliferation of epithelial cells of primary and secondary lamellae and resulting
fusion of secondary lamellae, hyperplasia and hypertrophy of mucous cells, focal inflammation and necrosis of epithelial cells)
were most severe at the two sampling sites upstream Arad city, which were shown to be polluted by copper, cadmium, faecal
coliforms and streptococci in a parallel study. At these two sites, also histopathology in the liver of L. cephalus was more prominent than at the two downstream sites. In C. nasus, symptoms in the liver (focal inflammation with lymphocytic infiltrations, macrophage aggregates and single cell necrosis)
were also highly pronounced at the sampling site located directly downstream the municipal sewage treatment plant of Arad.
With the exception of copper accumulation in L. cephalus caught at the most upstream sampling site, in both fish species cadmium and copper accumulation were exceptionally high and
did not differ significantly between the four sampling sites. 相似文献
288.
289.
Małgorzata Loga Anna Wierzchołowska-Dziedzic 《Environmental monitoring and assessment》2017,189(12):647
Measurement uncertainties are inherent to assessment of biological indices of water bodies. The effect of these uncertainties on the probability of misclassification of ecological status is the subject of this paper. Four Monte-Carlo (M-C) models were applied to simulate the occurrence of random errors in the measurements of metrics corresponding to four biological elements of surface waters: macrophytes, phytoplankton, phytobenthos, and benthic macroinvertebrates. Long series of error-prone measurement values of these metrics, generated by M-C models, were used to identify cases in which values of any of the four biological indices lay outside of the “true” water body class, i.e., outside the class assigned from the actual physical measurements. Fraction of such cases in the M-C generated series was used to estimate the probability of misclassification. The method is particularly useful for estimating the probability of misclassification of the ecological status of surface water bodies in the case of short sequences of measurements of biological indices. The results of the Monte-Carlo simulations show a relatively high sensitivity of this probability to measurement errors of the river macrophyte index (MIR) and high robustness to measurement errors of the benthic macroinvertebrate index (MMI). The proposed method of using Monte-Carlo models to estimate the probability of misclassification has significant potential for assessing the uncertainty of water body status reported to the EC by the EU member countries according to WFD. The method can be readily applied also in risk assessment of water management decisions before adopting the status dependent corrective actions. 相似文献
290.
This paper is based on a case study of the city of Girona in Catalonia, Spain, and analyses the vulnerability of commercial establishments to floods caused by the Onyar River. A mapping and statistical approach (cluster analysis) was applied to the information obtained from 568 questionnaires answered by the shops and the workshops located in the flood risk area. The results obtained allowed the authors to determine five different flood vulnerability profiles of the commercial establishments analysed. These profiles paint a picture of little individual adaptation to the risk and the possibility of suffering, sooner or later, large economic losses due to overflowing of the Onyar River. The authors established a methodology for carrying out a detailed multidimensional analysis of the flood vulnerability of the city's commercial establishments in order to provide the foundations for local government policies and for strategies for shop owners to reduce flood vulnerability. 相似文献