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1.
Objectives: Understanding health information-seeking behaviors and barriers to care and access among pregnant women can potentially moderate the consistent negative associations between poverty, low levels of literacy, and negative maternal and child health outcomes in India. Our seminal study explores health information needs, health information-seeking behaviors, and perceived information support of low-income pregnant women in rural India. Methods: Using the Wilson Model of health information-seeking framework, we designed a culturally tailored guided interview to assess information-seeking behaviors and barriers to information seeking among pregnant women. We used a local informant and health care worker to recruit 14 expectant women for two focus group interviews lasting 45 minutes to an hour each. Thirteen other related individuals including husbands, mothers, mothers-in-law, and health care providers were also recruited by hospital counselors for in-depth interviews regarding their pregnant wives/daughters and daughters-in-law. Interviews were transcribed and analyzed by coding the data into thematic categories. Results: The data were coded manually and emerging themes included pregnancy-related knowledge and misconceptions and personal, societal, and structural barriers, as well as risk perceptions and self-efficacy. Lack of access to health care and pregnancy-related health information led participants to rely heavily on information and misconceptions about pregnancy gleaned from elder women, friends, and mothers-in-law and husbands. Doctors and para-medical staff were only consulted during complications. All women faced personal, societal, and structural level barriers, including feelings of shame and embarrassment, fear of repercussion for discussing their pregnancies with their doctors, and inadequate time with their doctors. Conclusion: Lack of access and adequate health care information were of primary concern to pregnant women and their families. Policy Implications: Our study can help inform policies and multi-sectoral approaches that are being taken by the Indian government to reduce maternal and child morbidity and burdens. 相似文献
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Daniel J. Heilprin Charles R. Phillips Edward Basmadjian 《Environmental Biology of Fishes》2002,65(3):349-357
A widely recognized pathway for uptake and accumulation of organic contaminants by demersal fishes is through consumption of infaunal organisms (i.e., those having direct contact with contaminated sediments). Recent studies indicate that demersal fishes near a large sewage outfall in southern California consume larvae of a terrestrial fly, Clogmia albipunctata, which are entrained with the treated effluent and discharged to the ocean. Fly larvae consumption represents a possible method for accumulation of organic contaminants that is unique to marine fishes with non-selective feeding habits that occur near the ocean outfall. An estimated 37–138kg (wet weight) of fly larvae are discharged daily during summer to the ocean via the Orange County Sanitation Districts (OCSD) wastewater outfall; winter discharges are expected to be lower due to lower production and temperature limitations of the fly life cycle. Fly larvae were present in the guts of ten demersal and pelagic fish species collected near the outfall between July 1993 and August 1998. The highest frequencies of fly larvae (up to 100%) occurred in the guts of white croaker, Genyonemus lineatus, and chub mackerel, Scomber japonicus. Because infauna are still abundant and diverse near the outfall, fly larvae consumption appears to represent a feeding preference instead of a response to lower prey abundances. Fly larvae tissues collected at the wastewater treatment plant contained sub-part-per-million levels of organochlorine compounds, including PCB and DDT. However, lipid-normalized organochlorine concentrations in fly larvae tissues were not appreciably higher than levels in infauna or zooplankton tissues. Although the study design provided only limited sample sizes for some sample types, this initial study suggests that fish consumption of fly larvae represents a mechanism for direct transfer of contaminants and may contribute to uptake and accumulation of lypophyllic organochlorines in fish near the outfall. 相似文献
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Abstract A new interatomic potential model for H2O which consists of 2-body central (O-H, O-O and H-H) and 3-body teams and does not contain artificial constraints on the motions of oxygen and hydrogen atoms is proposed. The interatomic potential function parameters were determined empirically so as to reproduce the fundamental and essential features of water and ice Ih using molecular dynamics (MD) methods. We carried out the MD simulations of water, and find the Ice Ih, Ice II and Ice IX using this potential model, in structures and physical properties are in agreement with the experimental results except for the compressibilities of both water and ice Ih. We expect that, by refining this model, we can apply this model to problems involving the reaction of water molecules with other components. 相似文献
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Beatriz E. Perazzi Claudia I. Menghi Enrique F. Coppolillo Claudia Gatta Martha Cora Eliseth Ram��n A. de Torres Carlos A. Vay Angela M. R. Famiglietti 《The Korean journal of parasitology》2010,48(1):61-65
The objectives of this study were to conduct a prevalence survey of trichomoniasis in pregnant women and to evaluate the utility of different methods for its diagnosis. A total of 597 vaginal exudates from pregnant women who were examined at the Hospital de Clinicas in Buenos Aires, Argentina from 1 August 2005 to 31 January 2007, were prospectively and consecutively evaluated. The investigation of Trichomonas vaginalis was made by different microscopic examinations, and culture on liquid medium. The sensitivity and specificity of the microscopic examinations were assessed considering culture on liquid medium as the "gold standard". The prevalence of T. vaginalis obtained by culture on liquid medium was 4.0% (24/597). The prevalence of T. vaginalis obtained by direct wet smear, prolonged May-Grunwald Giemsa staining, and sodium acetate-formalin (SAF)/methylene blue staining-fixing technique was 1.8%, 2.3% and 2.5%, respectively. The sensitivity of the direct wet smear was 45.8%, that of the prolonged May-Grunwald Giemsa staining was 58.3%, and that of the SAF/methylene blue method was 62.5%. Considering the 3 microscopic examinations altogether, the sensitivity rose to 66.7% and the specificity was 100% for all of them. This is the first time that the prevalence data of T. vaginalis by culture in pregnant women are published in Argentina. Due to the low sensitivity obtained by microscopy in asymptomatic pregnant women, the use of the liquid medium is recommended during pregnancy, in order to provide an early diagnosis and treatment. 相似文献
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Vitor Camilo Cavalcante Dattoli Rafael Valente Veiga Sergio Souza Da Cunha Lain Carlos Pontes‐de‐Carvalho Maurício Lima Barreto Neuza Maria Alcântara‐Neves 《Helicobacter》2010,15(4):273-278
Background: Helicobacter pylori infection has been proved to be of great relevance to public health in unindustrialized countries, especially in low socioeconomic groups. Poor hygiene, deficient sanitation, and crowded conditions have been reported as risk factors for this infection. In this work, we investigated whether social and demographic characteristics were associated with anti‐H. pylori IgG antibodies in 1104 children aged 4–11 years old from Salvador, a large city located in northeastern Brazil. Methods: Standardized questionnaires were used to obtain social, demographic, and environmental data for the studied population in two periods of time (from 1997 to 2003 and in 2005). Anti‐H. pylori IgG antibodies were assessed by indirect enzyme‐linked immunosorbent assay in 2005. Results: Anti‐H. pylori IgG antibody was present in 28.7% of the children. Among the studied variables, the following were positively associated with the presence of anti‐H. pylori antibodies in multivariable analyses: age above 8 years old (OR = 1.72, 95% CI = 1.23–2.40), a larger sibling number (OR = 1.66, 95% CI = 1.26–2.18), nursery attendance (OR = 1.49, 95% CI = 1.04–2.12), location of the house at an unpaved street (OR = 2.03, 95% CI = 1.44–2.87) and absence of a flush toilet (OR = 1.32, 95% CI = 1.00–1.74). Conclusion: Our data show that H. pylori infection in children from a major Brazilian city is associated with variables indicative of a crowded environment and deficient sanitation/habitation conditions, leading to the conclusion that improvements in hygiene and social conditions may protect children against this infection. 相似文献
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Adaptive developmental plasticity can enable an organism to modify its phenotype rapidly, in response to local(and perhaps, unpredictable) conditions, by altering reaction norms during development. Previous studies on this topic have been dominated by western scientists, employing western study systems and approaches. Recently, the expansion of Chinese ecological research has seen a broadening of studies taxonomically(phylogenetically). Here, we briefly summarize research that has been conducted on developmental plasticity in Chinese reptiles over the past two decades, and suggest productive directions for future studies in this field. There are exciting research opportunities in this field in China, and we call for increased collaboration between western and eastern scientists to elucidate the role of developmental plasticity in evolutionary responses of organisms to environmental changes. As human activities increase the intensity and frequency of such changes, the need to understand responses of biological systems becomes an increasingly urgent priority. 相似文献
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N. S. Duzgoren-Aydin C. S. C. Wong Z. G. Song A. Aydin X. D. Li M. You 《人类与生态风险评估》2006,12(2):374-389
The urban environment of Guangzhou, the largest industrialized center in SE China, has elevated levels of heavy metals. In places, Cu, Pb, and Zn contents exceed 490, 920, and 1,820 mg/kg, respectively. The accumulation of these contaminants is likely to accelerate as a consequence of rapid economic and industrial growth in the region. Understanding of the possible fate of the contaminants is therefore imperative in order to assess their potential long-term ecological impacts. This article documents the results of a sequential extraction procedure involving five operationally defined fractions to determine the chemical partitioning of Cu, Pb, and Zn in the urban deposits represented by road dusts and corresponding gully sediments. Special emphasis was given to the mineralogical characteristics of the urban deposits. Road dusts were mainly composed of quartz, K-Feldspar, plagioclase, and calcite, and contained minor amounts of mica and clay minerals. The corresponding gully sediments, however, typically contained minor amounts of calcite, mica, and clay minerals, and were dominated by quartz and K-feldspar. The road dusts and gully sediments exhibited comparable chemical partitioning patterns of Cu, Pb, and Zn, despite significant differences in the relative abundances of minerals, especially of calcite. Lead and Zn occurred mainly in the operationally defined carbonate/ specifically adsorbed (Pb: 48%; Zn: 50%) and Fe-Mn (Pb: 36%; Zn: 27%) phases, whereas Cu was largely associated with the organic (70%) and residual (15%) phases. In general, the residual phases of the heavy metal contaminants were equal or less than 15%, suggesting their dominantly anthropogenic origin. The relative mobility and bioavailability of the heavy metals in the urban deposits of Guangzhou was: Pb ~ Zn > Cu. The ever-increasing accumulations of heavy metals may pose a threat in the region both to the environment and to human health. 相似文献
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Gustavo R. B. Miranda Carlos G. Raetano Emília Silva Michiel A. Daam Maria José Cerejeira 《人类与生态风险评估》2011,17(4):981-995
Due to their reported high toxicity to honey bees, ecotoxicological studies into the side-effects of neonicotinoid insecticides have focused almost exclusively on these organisms. The fate of neonicotinoids and potential toxic side-effects on other (especially non-standard) organisms have received considerably less attention. In the present study, the environmental distribution and leaching potential of neonicotinoids registered for agricultural use in Brazil (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam) were studied by applying several environmental fate models and indices. Potential risks to various environmental compartments were evaluated by applying ranking indices to the maximum application rates recommended in Brazil. Although bees were indeed found to be the most sensitive organism, the neonicotinoids also indicated potential environmental risks to other organism groups. Due to the greater maximum application rates recommended in Brazil as compared to other parts of the world, environmental risk and resistance potential for at least imidacloprid appears especially high in Brazil. Attention should thus also be allocated to organisms other than bees and to resistance potential when performing an environmental risk assessment of neonicotinoids if they are used at relatively high application rates. 相似文献
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Sandy clay loam soil contaminated with 5000, 10,000 or 20,000 mg/kg of diesel fuel no. 2 was amended with 0 (ambient nitrogen only), 250, 500, or 1000 mg/kg nitrogen (NH4Cl) to evaluate the role of C:N ratios and soil water potential on diesel biodegradation efficacy. The soil was incubated at 25°C for 41 days and microbial O2 consumption measured respirometrically. Highest microbial respiration was observed in the 250 mg N/kg soil treatments regardless of diesel concentration. Higher levels of nitrogen fertilization decreased soil water potential and resulted in an extended lag phase and reduced respiration. Application of 1000 mg/kg nitrogen reduced maximum respiration by 20% to 52% depending on contaminant levels. Optimal C:N ratios among those tested were 17:1, 34:1, and 68:1 for the three diesel concentrations, respectively, and were dependent on contaminant concentration. Nitrogen fertilization on the basis of soil pore water nitrogen (mg N/kg soil H2O) is independent of hydrocarbon concentration but takes into account soil moisture content. This method accounts for both the nutritional and osmotic aspects of nitrogen fertilization. In the soil studied the best nitrogen augmentation corresponded to a soil pore water nitrogen level of 1950 mg N/kg H2O at all diesel concentrations. 相似文献
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The distribution of physiological daily inhalation rates for pregnant and lactating females aged 11 to 55 years was determined according to total daily energy expenditures, energy costs for growth, pregnancy and lactation (maternal milk-energy synthesis and breast-energy output) in free-living females. Such published data were obtained using a methodology based on the disappearance rates of predetermined doses of doubly labeled water (2H2O and H2 18O) in urine from non-pregnant and non-lactating females (n = 357), as well as saliva from gravid and breastfeeding females (n = 91), monitored by gas-isotope-ratio mass spectrometry over an aggregate period of about 6,000 days. Monte Carlo simulations were necessary to integrate total daily energy requirements of non-pregnant and non-lactating females into energy costs and weight changes at the 9th, 22nd, and 36th week of pregnancy and at the 6th and 27th, postpartum week: 540,000 data were simulated. The present article confirms that physiological daily inhalation rates for under-, normal-, and overweight/obese pregnant and lactating females expressed in m3/day and m3/kg-day are higher than those for males. For instance, in normal-weight subjects, inhalation rates are higher by 18 to 41% throughout pregnancy and 23 to 39% during postpartum weeks: actual values were higher in females by 1.13 to 2.01 m3/day at the 9th week of pregnancy, 3.74 to 4.53 m3/day at the 22nd week and 4.41 to 5.20 m3/day at the 36th week, and by 4.43 to 5.30 m3/day at the 6th postpartum week and 4.22 to 5.11 m3/day at the 27th postpartum week. The highest 99th percentiles were found to be 0.622 m3/kg-day in pregnant females and 0.647 m3/kg-day in lactating females. By comparison, the highest 99th percentile value for individuals aged 2.6 months to 96 years was determined to be 0.725 m3/kg-day in Brochu et al. (2006a). Air quality criteria and standard calculations based on the latter value for non-carcinogenic toxic compounds should therefore be protective for virtually all pregnant and lactating females. The present article highlights evidence that the current default assumption regarding the total daily air intake used by the Integrated Risk Information System (IRIS) to derive human equivalent concentrations in reference dose calculations is also underestimated compared to some higher 75th and 90th percentiles of physiological daily inhalation rates in pregnant and lactating females. 相似文献
12.
Sandy clay loam soil contaminated with 5000, 10,000 or 20,000 mg/kg of diesel fuel no. 2 was amended with 0 (ambient nitrogen only), 250, 500, or 1000 mg/kg nitrogen (NH4Cl) to evaluate the role of C:N ratios and soil water potential on diesel biodegradation efficacy. The soil was incubated at 25°C for 41 days and microbial O2 consumption measured respirometrically. Highest microbial respiration was observed in the 250 mg N/kg soil treatments regardless of diesel concentration. Higher levels of nitrogen fertilization decreased soil water potential and resulted in an extended lag phase and reduced respiration. Application of 1000 mg/kg nitrogen reduced maximum respiration by 20% to 52% depending on contaminant levels. Optimal C:N ratios among those tested were 17:1, 34:1, and 68:1 for the three diesel concentrations, respectively, and were dependent on contaminant concentration. Nitrogen fertilization on the basis of soil pore water nitrogen (mg N/kg soil H2O) is independent of hydrocarbon concentration but takes into account soil moisture content. This method accounts for both the nutritional and osmotic aspects of nitrogen fertilization. In the soil studied the best nitrogen augmentation corresponded to a soil pore water nitrogen level of 1950 mg N/kg H2O at all diesel concentrations. 相似文献
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This article presents the rationale for the mathematical fate and transport model, which has been provided in the accompanying spreadsheet (GWProt). This spreadsheet model may be used as a simple and scientifically defensible regulatory tool for determining the risk-based soil clean up level of petroleum release sites to protect groundwater quality. The model incorporates either a three- or four-phase partitioning equilibrium mechanism, depending on the detection of Non-Aqueous Phase Liquid phase presence mathematically, as well as Raoult's Law convention and default dilution and attenuation factors. A database of contaminant-specific parameters, including solubility and organic-carbon partition-coefficient, molecular weight, and Henry's Law constant, is assembled for benzene, toluene, ethylbenzene, xylenes, and 12 other TPH equivalent carbon fractions. In addition to distributing organic chemicals among aqueous, sorbed solid, air, and NAPL phases, according to traditional partitioning equations, the algorithm incorporates equations for the conservation of mass and volume. A unique solution is obtained by solving a series of mass balance equations simultaneously using the iterative spreadsheet routine built in MICROSOFT EXCELTM Solver — with the restrictions that the volume is conserved and the sum of the mole fractions is equal to one. Sample calculations are presented for a range of parameter values to illustrate the use of the model and the relative leach-ability of a wide range of representative fuels. Sensitivity analysis was also performed to quantify the effects of uncertainty in the estimates of the key model parameters on model results. Model predictions were compared with the results from a water-fuel experiment. The noncar-cinogenic Hazard Index (HI) for groundwater through direct ingestion was calculated using predetermined oral reference dose (Rfd) values. Applications and limitations of the model are also discussed. 相似文献
16.
Fluctuating asymmetry and age in children: evolutionary implications for the control of developmental stability 总被引:1,自引:0,他引:1
Fluctuating asymmetry (FA) is small deviations from perfect symmetry which reflect one component of fitness, i.e. developmental stability. There is accumulating evidence that low FA is important in inter- and intra-sexual selection in humans. However, there is little information on the pattern of FA in children. Data from cross-sectional studies of 680 participants from 2–18 years suggests that (1) both absolute and relative FA reduces with age until 10 years (2) there is an increase in FA in adolescents (11–15 years) with a peak at 13 years for males and 14 years for females (3) after 15 years there is reduction in FA which is maintained until 18 years. The importance of growth rate, metabolic maintenance and sex steroids on developmental stability is discussed. 相似文献
17.
Julia L. Blanchard Simon Jennings Robert Holmes James Harle Gorka Merino J. Icarus Allen Jason Holt Nicholas K. Dulvy Manuel Barange 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2012,367(1605):2979-2989
Existing methods to predict the effects of climate change on the biomass and production of marine communities are predicated on modelling the interactions and dynamics of individual species, a very challenging approach when interactions and distributions are changing and little is known about the ecological mechanisms driving the responses of many species. An informative parallel approach is to develop size-based methods. These capture the properties of food webs that describe energy flux and production at a particular size, independent of species'' ecology. We couple a physical–biogeochemical model with a dynamic, size-based food web model to predict the future effects of climate change on fish biomass and production in 11 large regional shelf seas, with and without fishing effects. Changes in potential fish production are shown to most strongly mirror changes in phytoplankton production. We project declines of 30–60% in potential fish production across some important areas of tropical shelf and upwelling seas, most notably in the eastern Indo-Pacific, the northern Humboldt and the North Canary Current. Conversely, in some areas of the high latitude shelf seas, the production of pelagic predators was projected to increase by 28–89%. 相似文献
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Climate change is expected to cause changes in precipitation quantity, intensity, frequency and duration, which will subsequently
alter environmental conditions and might increase the risk of waterborne disease. The objective of this study was to describe
the seasonality of and explore associations between weather, water quality and occurrence of infectious gastrointestinal illnesses
(IGI) in two communities in Nunatsiavut, Canada. Weather data were obtained from meteorological stations in Nain (2005–2008)
and Rigolet (2008). Free-chlorine residual levels in drinking water were extracted from municipal records (2005–2008). Raw
surface water was tested weekly for total coliform and E. coli counts. Daily counts of IGI-related clinic visits were obtained from health clinic registries (2005–2008). Analysis of weather
and health variables included seasonal-trend decomposition procedures based on Loess. Multivariable zero-inflated Poisson
regression was used to examine potential associations between weather events (considering 0–4 week lag periods) and IGI-related
clinic visits. In Nain, water volume input (rainfall + snowmelt) peaked in spring and summer and was positively associated
with levels of raw water bacteriological variables. The number of IGI-related clinic visits peaked in the summer and fall
months. Significant positive associations were observed between high levels of water volume input 2 and 4 weeks prior, and
IGI-related clinic visits (P < 0.05). This study is the first to systematically gather, analyse and compare baseline data on weather, water quality and
health in Nunatsiavut, and illustrates the need for high quality temporal baseline information to allow for detection of future
impacts of climate change on regional Inuit human and environmental health. 相似文献
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宁夏扶贫扬黄灌溉工程环境移民及影响评价王谋孙丽波(宁夏环境保护研究所,银川750021)(西北轴承集团职工医院,银川750021)马柯(宁夏环境监测中心站,银川750021)EnvironmentalImmigrationofPumpingWate... 相似文献