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Sources of phthalates other than Polyvinyl chloride (PVC) related products are scarcely documented in Mexico. The objective of our study was to explore the association between urinary levels of nine phthalate metabolites and the use of personal care products. Subjects included 108 women who participated as controls in an ongoing population-based case-control study of environmental factors and genetic susceptibility to breast cancer in northern Mexico. Direct interviews were performed to inquire about sociodemographic characteristics, reproductive history, use of personal care products, and diet. Phthalate metabolites measured in urine by high performance liquid chromatography-isotope dilution tandem mass spectrometry were monoethyl phthalate (MEP), monobenzyl phthalate (MBzP), mono-n-butyl phthalate (MBP), mono-isobutyl phthalate (MiBP), mono-3-carboxypropyl phthalate (MCPP) as well as mono-2-ethylhexyl phthalate (MEHP), mono-2-ethyl-5-oxohexyl phthalate (MEOHP), mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP), mono-2-ethyl-5-carboxypentyl phthalate (MECPP) that are metabolites of di-ethylhexyl phthalate (DEHP). Detectable urinary concentrations of phthalate metabolites varied from 75% (MEHP) to 100% (MEP, MBP, MEOHP, MEHHP and MECPP). Medians of urinary concentrations of some phthalate metabolites were significantly higher among users of the following personal care products compared to nonusers: body lotion (MEHHP, MECPP and sum of DEHP metabolites (ΣDEHP)), deodorant (MEHP and ΣDEHP), perfume (MiBP), anti-aging facial cream (MEP, MBP and MCPP) and bottled water (MCPP, MEHHP and MEOHP). Urinary concentrations of MEP showed a positive relationship with the number of personal care products used. Our results suggest that the use of some personal care products contributes to phthalate body burden that deserves attention due to its potential health impact.  相似文献   
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Rural households throughout the Himalayas are regarded as dependent on non-timber forest products (NTFPs), but very few studies have quantified this dependency. This case study, undertaken in two villages in the Central Himalayan foot hills in Nepal, documents the absolute and relative importance of commercial NTFPs to rural household economies. Data were collected in a one-year period and included interviews with 250 households using a semi-structured questionnaire and monthly interviews with four sub-local NTFP traders, two local traders and two central wholesalers. The conservative estimate of NTFP-derived cash income showed this to be a cornerstone in poorer household livelihood strategies and thus in poverty prevention. An annual average of 578 kg of commercial NTFPs was collected in the wild per household, providing poorer households with a cash income share of 44–78%. Better off households are not NTFP dependent but rely on income from crop production and livestock. Based on a net marketing margin analysis, showing that harvesters capture a large share of the Indian wholesaler price, it is argued that there is scope for pursuing NTFP-based strategies for poverty reduction through leasehold forestry and agroforestry. Both these options are compatible with conserving forest cover and forest corridor functions and may thus present a win–win scenario for livelihood improvement and conservation.  相似文献   
55.
Forest income and dependency in lowland Bolivia   总被引:1,自引:0,他引:1  
Forests contribute to livelihoods of rural people throughout the tropics. This paper adds to the emerging body of quantitative knowledge on absolute and relative economic importance, through both cash and subsistence income, of moist forests to households. Qualitative contextual information was collected in six villages in lowland Bolivia, followed by a structured survey of randomly selected households (n = 118) that included four quarterly income surveys. We employed a novel data collection approach that allows detailed estimation of total household accounts, including sources of forest income. We estimated the average forest income share of total annual household income (forest dependency) at 20%, ranging from 18 to 24%. Adding environmental income increased the average to 26%, being fairly constant across income quartiles at 24–28%. Absolute levels of forest income increased with total household income, while forest dependency was the highest in the best-off income quartile—the primary harvesters of forest products are better-off households. The pattern of high forest dependency among better-off households has also been reported from other countries, indicating that this pattern may be more common than advocated by conventional wisdom. Using ordinary least squares (OLS) regressions, we found significant determinants of absolute forest income to be household size, sex of household head and area of cultivated land; the significant determinants for forest dependency were level of education, whether household head was born in village and whether household was food self-sufficient. Better-off households were able to realise cash income from forests, while poorer households—in particular if headed by women—were more reliant on subsistence forest income. We argue that the differential patterns of forest income across income quartiles should be considered in future development interventions and that findings indicate a potential for forests to contribute to moving households out of poverty.  相似文献   
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The prenatal diagnosis, management and outcome of an hereditary obstructive uropathy is presented. Serial ultrasonic assessment of the fetal urinary tract was carried out from the early second trimester onward. Slight bilateral hydronephrosis as a first sign of obstructive uropathy was only established as late as 30 weeks of gestation. On the basis of weekly ultrasound scans, a conservative approach was adopted. In view of fetal maturity, labour was induced at 36 weeks resulting in the vaginal delivery of a male infant with moderate bilateral hydronephrosis. Neonatally, anuria developed due to bilateral obstruction of the ureters as a result of increasing bladder wall hypertrophy due to urethral valves. A bilateral uretero-cutaneostomy was carried out. The infant so far develops normally, and renal function is normal for age. Women at risk for fetal obstructive uropathy should have ultrasonic monitoring throughout pregnancy.  相似文献   
57.
 On the highly productive Oman Margin of the Arabian Sea, where an intense permanent oxygen minimum impinges on the continental slope, there is no relationship between oxygen concentration and sedimentary organic-carbon content. However, we provide photographic and molecular evidence that benthic invertebrates play a significant role in the redistribution of organic matter. High densities of spider crabs and brittle stars characterize a narrow band near the base of the oxygen minimum zone, where sediments have depleted organic carbon contents and a remarkable lipid composition that is indicative of metabolic alteration of phytoplankton-derived sterols by invertebrate detritivores. The distributions of sedimentary sterols and the high abundances of epifaunal crabs and brittle stars suggest that the metabolism of the megabenthos profoundly influences the quality of organic matter in underlying sediments. Received: 12 June 1998 / Accepted in revised form: 26 January 1999  相似文献   
58.
  Die geschichtliche Entwicklung der kosmologischen Modelle für den homogen–isotropen Kosmos, beginnend mit Alexander Friedmanns epochalen Arbeiten (1922 und 1924) bis zur heutigen Diskussion aktueller Modelle wird dargestellt. Eine kardinale Rolle spielt die offene Frage: Besteht die Materie des Kosmos zum weit überwiegenden Teil aus nicht–baryonischer (sog. exotischer) Dunkel–Materie oder reicht die gesamte baryonische Materie aus, die aus den bekannten Atomen und Molekülen besteht, um die Entwicklung des Kosmos zu verstehen. Auch von der normalen (baryonischen) Materie im Kosmos ist nur ein geringer Anteil (etwa 20 5 Prozent) in leuchtenden Objekten (Sterne, Gas, Staub) direkt beobachtbar. Im Abschnitt 3 wird der “Einstein–Limit” für die kosmologische Konstante erl?utert und eine leicht einsichtige Herleitung des Zahlenwertes gegeben.  相似文献   
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Territoriality is of great significance for many species and a characteristic of most group-living animals. Territoriality is thought to lead to increased reproductive success by defending a particular area containing critical resources. I describe several factors that influence territorial aggression in free-ranging striped mice (Rhabdomys pumilio), a group-living solitary forager. I induced territorial aggression by attracting mice of different groups using bait either at territory boundaries or in front of nests. Striped mice are territorial and make decisions about whether or not to attack a mouse from another group based upon several factors: (1) the sex of the opponent: males are much more likely to attack strange males than strange females, whereas no sex specific aggression was observed in females; (2) the body size of the opponent: striped mice are much more likely to attack a strange mouse that is lighter than themselves; and (3) the location of encounters: striped mice are much more likely to attack strangers, even those significantly heavier than themselves, in front of the nest than at territory boundaries. These variations in territorial responses between different types of individuals may be due to the different ultimate consequences of territorial aggression for different animals.Communicated by S. Alberts  相似文献   
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