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1.
A polyphasic PCR-DGGE approach was used to describe the microbial population occurring in natural whey cultures (NWCs) for water-buffalo Mozzarella cheese production. Total microbial community was assessed without cultivation by analyzing DNA directly extracted from the original samples of NWC. In addition, DNA extracted from bulks of cells formed by harvesting colonies from the serial dilution agar plates of a variety of culture media was used to profile the "cultivable" community. The 16S rDNA V3 region was amplified using DNA from NWC as well as DNA from bulks as templates and the amplicons were separated by DGGE. The microbial entities occurring in NWCs were identified by partial 16S rDNA sequencing of DGGE bands: four lactic acid bacteria (LAB) closest relative of Streptococcus thermophilus, Lactococcus lactis, Lactobacillus delbrueckii and Lactobacillus crispatus were revealed by the analysis of DNA directly extracted from NWC while two other LAB, Lactobacillus fermentum and Enterococcus faecalis, were identified by analyzing DNA from the cultivable community. The developed PCR-DGGE analysis of the "cultivable" community showed good potential in evaluating microbial diversity of a dairy environment: it usefully highlighted the bias introduced by selective amplification when compared to the analysis of the total community from NWC and allowed suitability of media and growth conditions to be evaluated. Moreover, it could be used to complete the culture independent study of microbial diversity to give information on concentration ratios among species occurring in a particular environment and can be proposed for rapid identification of dominant microorganisms in alternative to traditional tools.  相似文献   

2.
We screened samples from high temperature biotopes for 16S rRNA genes of the novel archaeal phylum "Nanoarchaeota". Positive PCR amplifications were obtained from Yellowstone National Park, Uzon Caldera, and an abyssal vent system. These sequences form a cluster with the sequence of "Nanoarchaeum equitans", indicating a wide distribution of this phylum.  相似文献   

3.
4.
The potential dermal and respiratory exposure and risk assessments for an applicator were performed with chromafenozide in rice fields in Korea. Three experienced farmers of approximately the same height (168–170 cm) and weight (65–73 kg) were employed to perform the experiment. Dermal patches, gloves, socks, and masks were used to monitor the potential dermal exposure (PDE), and personal air samplers with XAD-2 resins were used to monitor the potential inhalation exposure. During the mixing/loading process of chromafenozide (2.5%, EC), the average hand exposure amount was 3.7 mg and the ratio to the applied amount was 1.85 ×10?2%. For spraying process, the potential dermal exposure amount was 98.3 (74.5–112.8) mg, corresponding to 0.492% of the total exposure amount. The major exposure parts were thigh (0.37%) and shin (0.10%), and the left body (55.0%) was more than that of the right body (45.0%). The inhalation exposure amount was only 39.9 mg. For risk assessment, the mean of PDE (384.0 mg/day) and the mean of absorbable quantity of exposure (3.99 mg/day) were calculated. The value of margin of safety (MOS) ranged from 1.12 to 1.69, all MOS were >1, indicating the exposure level of chromafenozide was safe during application in rice fields.  相似文献   

5.
Environmental problems, such as global warming, the limited supply of sustainable energy, the depletion of natural resources, hazardous emissions released into the atmosphere and waste, are increasing global concerns. Therefore, individuals, communities, and businesses need to address environmental protection and sustainability. Environmental impact assessments are needed to identify, mitigate, and control aspects that affect the environment or a company's products, services, or activities. In this study, a general environmental aspect and impact assessment approach, which can be applied to any company that is involved in the production or service sector, is created. An environmental impact pattern that consists of 10 main and 32 sub-categories was formed based on the ISO 14001, environmental studies and field applications. The developed approach was applied to the dyeing units of a manufacturing firm. Sixteen environmental aspects were identified and assessed using the environmental impact template via the environmental failure mode and effect analysis (E-FMEA) method. The developed-approach can be applied to each sector, which will enable us to perform a detailed analysis of the environmental aspects in the environmental impact category. This approach provides a checklist for the environmental impact studies of businesses and has been pioneered as an effective method for company resources to improve their environmental performance.  相似文献   

6.
To manage public health and make better use of groundwater resources, the concentration characteristics and a health risk assessment of eight heavy metals in shallow groundwater were studied. Besides this, this paper introduced triangular fuzzy numbers into the USEPA health risk assessment model to assess the health risk posed to local children and adults through different exposure pathways. The results showed that Mn levels exceeded the WHO’s guideline values of 100?µg/L with the proportion of 27.98% and Sr were over the health reference level (HRL) of 1500?µg/L with the proportion of 56.25%, while other heavy metals were below the corresponding standard. The results of the HRA showed that the non-carcinogenic risks from Sr and Mn in the district were relatively higher, while those from the remaining six heavy metals were relatively lower. All hazard index (HI) values did not exceed the safety level of 1 for either age group. The average carcinogenic risk from Cr was slightly higher than the acceptable level of 1?×?10?6 for adults. Sensitivity analyses conducted using Monte Carlo simulation indicated that Sr and Cr concentrations were the most influential variables contributing to the non-carcinogenic and carcinogenic risk values, respectively, while body weight had a minor contribution.  相似文献   

7.
Connexin43 (Cx43) is a membrane-spanning protein that forms channels that bridge the gap between adjacent cells and this allows for the intercellular exchange of information. Cx43 is regulated by phosphorylation and by interacting proteins. “Mode-1” interaction with 14-3-3 requires phosphorylation of Ser373 on Cx43 (Park et al. 2006). Akt phosphorylates and targets a number of proteins to interactions with 14-3-3. Here we demonstrate that Akt phosphorylates Cx43 on Ser373 and Ser369; antibodies recognizing Akt-phosphorylated sites or phospho-Ser “mode-1” 14-3-3-binding sites recognize a protein from EGF-treated cells that migrates as Cx43, and GST-14-3-3 binds to Cx43 phosphorylated endogenously in EGF-treated cells. Confocal microscopy supports the co-localization of Cx43 with Akt and with 14-3-3 at the outer edges of gap junctional plaques. These data suggest that Akt could target Cx43 to an interaction with 14-3-3 that may play a role in the forward trafficking of Cx43 multimers and/or their incorporation into existing gap junctional plaques.  相似文献   

8.
Although bright light treatment may alleviate the symptoms of winter depression, it still remains to be clarified whether chronobiological mechanisms are involved in this antidepressant response. We studied the therapeutic action of bright light in 61 women with and 36 women without winter depression at the medical academic hospital near Novosibirsk (55 degrees North). Bright light was administered with cool-white incandescent lamp for seven days, two hours daily. The treatment started from either 8:00 (n = 29 patients and 16 controls) or 16:00 (n = 24 and 14, respectively) or 18:00 (n = 8 and 6, respectively). The subsets of bright light-treated subjects were then restudied in wintertime before and after one-week vacation in Firuza resort (south of Turkmeniya, 38 degrees North) (n = 19 and 0, respectively), in summertime (n = 42 and 18, respectively) and in the next winter before and after a week 30-min exposure in the morning hours to dim red light emitting “Light Cap” (n = 9 and 0, respectively). The results suggest that, in controls, mood slightly but statistically significantly improved after light treatment and in summer. In patients, the improvement of mood after one week of bright light was comparable with the effects of such “natural” treatments as trips south and transition from winter to summer seasons. Although next winter response to 0.5-h dim light was clinically significant, it was significantly worse compared to the previous response to 2-h bright light. Our therapeutic results indicate that, despite the different potential phase-shifting effect of bright light administered in the morning and in the second half of the day, the responses to all treatments are equally beneficial. This finding provides evidence against the view that circadian phase shifts are the key to the pathogenesis of winter depression and efficacy of light therapy. Although several different physiological effects of light therapy might be involved in the antidepressant response, none of them seems to be of more importance compared to psychological components of this response. Ours and earlier published reports on the independence of beneficial action of bright light from treatment timing support the suggestion that, in the open investigational trials, the placebo effect accounts for a large portion of the antidepressant response. We also reviewed several facts pointing to the close dependence of antidepressant effects of non-drug therapy upon patients' expectations and researchers' enthusiasm. In sum, unlike patients' chronobiology, their psychology seems to be most powerful mediator of the clinical response to bright light.  相似文献   

9.
Numerical simulation-based health risk assessment for contaminated groundwater is computationally costly. This study presents a meta-model-based statistical framework to create a series of rapid response for capturing the relations between remediation strategies (pumping rates at the wells) and remediation performance (contaminant concentrations). The meta-model is used to predict the naphthalene concentrations in groundwater under the assumption that remedial action would be implemented in 3, 5, 7, and 10 years of remediation, respectively. The simulation results from the meta-model are used as the input parameters for health risk assessment. This meta-analysis approach is applied to a naphthalene-contaminated aquifer located in a power plant in Anhui province, China. Results reveal that the exceeding level of the peak excess lifetime cancer risk is much greater than that of naphthalene concentration as compared with their environmental standards. It is also demonstrated that the proposed framework is particularly suitable to instant health risk assessment, which brings a bridge to assist in mathematically designing optimal groundwater remediation systems.  相似文献   

10.
M.J. Bibb  P.R. Findlay  M.W. Johnson   《Gene》1984,30(1-3):157-166
Bacterial genes that code for proteins appear to possess a codon usage characteristic of their overall base composition. This results in different but predictable non-random distributions of nucleotides within codons, permitting the recognition of protein-coding sequences in a wide range of bacterial species. The nature of this distribution depends on the base composition of the coding sequence. The position-specific differences are especially conspicuous in genes of extreme G + C content, allowing the particularly reliable prediction of the reading frame and coding strand of experimentally determined DNA sequences. This fmding has been exploited to identify the coding sequence of the viomycin phosphotransferase (vph) gene of Streptomyces vinaceus. An easily applied computer program (“Frame”) has been written to carry out and display such analyses.  相似文献   

11.
With rapid industrialization and modernization in China, long-term dietary exposure to cadmium (Cd) has the potential to cause health risks. The traditional probabilistic approach for long-term dietary assessment was a semi-probabilistic method that had limitations in qualifying the variation in concentration data. Thus, this article estimated the long-term dietary exposure to Cd of the adults of Jiangsu province using semi-probabilistic and fully probabilistic approaches, and compared the two models. Cd concentration data were obtained from the national food contamination monitoring program 2001–2009. Food consumption data were gathered from the National Diet and Nutrition Survey conducted in 2002. The provisional tolerable daily intakes (PTDI) of 0.8 μg kg–1 bw for Cd was applied in the risk assessment. The estimates of semi-probabilistic approach were within the provisional tolerable daily intakes (PTDI) at mean and all percentiles. However, the P95 of exposure with fully probabilistic approach for all population groups were above PTDI. Rice and rice products followed by wheat flour and wheat flour products, crustaceans, pak-choi, beans, and bean products contributed most to the Cd intake for adults. The fully probabilistic estimates could indicate a possible public health concern on Cd for adults in Jiangsu province.  相似文献   

12.
Abstract

Ambient PM2.5 data in the Central Business District (CBD) of Bangkok monitored by Pollution Control Department and Bangkok Metropolitan Administration were collected over three years in Bangkok from 2015 to 2017. The other air pollutions data were used as the dependent variables to develop mathematic models with statistical distribution technique. Multiple linear regression technique was selected as the main statistical distribution methodology for estimating PM2.5 concentrations in non-monitored areas. The predicted PM2.5 concentrations were validated against the measured PM2.5 concentrations by various statistical techniques. The validation found that the model had strong significant correlations for ambient and roadside area with R 2?=?0.88 and 0.96, respectively. The non-carcinogenic health risk assessment of PM2.5 was quantified as the hazard quotient (HQ) from both the measured and predicted data. The risk areas and HQ were compared using the inverse distance weighting interpolation technique and illustrated as GIS-based maps. During December to February, the HQ values of PM2.5 were exceed 1 (HQs?>?1) at all area of CBD; however, the highest HQ was found in the southern part of CBD. The finding could be used for residential health awareness in that area.  相似文献   

13.
The present study was aimed at assessing drinking water quality regarding arsenic (As) and its impact on health from Mailsi (Punjab), Pakistan. Forty-four groundwater samples were collected from two sites, Sargana and Mailsi. Arsenic and other cations were determined by atomic absorption spectrophotometer, whereas the anions were determined either through titration or spectrophotometer. The results revealed that dominant anions were HCO3? and Cl?, Ca+2 was the dominant cation, and overall water chemistry of the area was CaMgHCO3? type. Arsenic concentrations were high, ranging from 11 to 828 µg/L that crossed the World Health Organization permissible limits. Likewise, higher SO4?2 concentrations ranging from 247 to 1053 mg/L were observed. The health risk index was higher in the Sargana site, which employed the differences in terms of higher Average Daily Dose, Hazard Quotient, and Carcinogenic Risk of arsenic, which is unsuitable for drinking purposes. The area seems to be at high risk due to arsenic pollution and wells have never been tested for arsenic concentrations earlier; therefore, necessary measures should be taken to test the wells with respect to arsenic.  相似文献   

14.
In this study, the content and bioaccessibility of rare earth elements (REEs) in Porphyra spp. Samples before and after thermal treatments were investigated. Additionally, the risks of REEs exposure to human health were assessed. REEs content significantly reduced after thermal processing (P < 0.01), and the removal rate of REEs was approximately 30%. Thermal treatment increased REEs bioaccessibility from 44% to 64.34%. The concentration and bioaccessibility of Ce, La, Y, Nd were high in raw and thermally treated Porphyra samples, and there was no correlation between REEs content and bioaccessibility. Based on the following parameters: highest content of REEs in the studied seaweed samples (13.45 mg/kg), the highest daily seafood consumption (44.9 g/day), and the highest bioaccessibility (64.34%), the ratio of the calculated daily intake (DI) to daily allowable intake by diet (DAIdiet) of REEs did not exceed the reference value in rare earth mining areas or under extreme conditions. The DI via seafood consumption would be exceeded when the content of REEs in the seafood sample is greater than 15.77 mg/kg. In this study, the concentration of REEs did not exceed 15.77 mg/kg in any sample. Thus, the human health risks of REEs associated with seafood are low.  相似文献   

15.
With the increasing development of the petrochemical industry and the growing demand for oil, polycyclic aromatic hydrocarbons (PAHs) pollutions in the environment, especially in petroleum exploitation areas, are caused by the discharge of waste from the petroleum extraction process into an environmental system. This study aims to develop a new health risk assessment approach based on interval dynamic multimedia fugacity (IDMF) model and uncertainty analysis that could analyze the human exposure risk level for PAH contamination. The developed IDM health risk assessment (IDMHRA) approach is applied to assess previous, current, and future risks at a case study site in Daqing, Heilongjiang, China, from 1985 to 2020 for model validation. The human health risk assessment results show that 11 PAHs (NAP, ANT, FLA, PYR, BaA, CHR, BbF, BkF, BaP, IPY, and DBA) in the study site require further remediation efforts in terms of their unacceptable non-carcinogenic and carcinogenic risk. The results of risk source analysis reveal that soil media is the main risk pathway as compared with other exposure pathways. It can be seen that remediation process for soil contamination in the study site is urgently demanded. The assessment results demonstrate that the developed IDMHRA approach provides an effective tool for decision-makers and environmental managers to make remediation decisions in contaminated sites.  相似文献   

16.
Increased use of the world's natural resources, including water bodies such as the Chesapeake Bay, has resulted in additional burdens being placed on them. If continued, unrestricted use of such resources continues, degradation will occur to such an extent that some areas will be unsuitable for economic, social, and environmental uses. Regional risk assessment strategies must be developed so that actual or perceived risks can be evaluated and predicted on a regional scale. This article presents an initial strategy for the Chesapeake Bay that may be useful to scientists, managers, and elected officials responsible for other bodies of water as well. This article reviews risk assessment practices and proposes a strategy that utilizes appropriate endpoints to ascertain and predict risk.  相似文献   

17.
Risk assessment, both human and ecological, embodies fundamental assumptions about hydrological processes, especially how they affect the movement of contaminants in the environment. The lateral movement of water through the soil, or interflow, is frequently a component of risk assessments for humid environments, but not of those for semiarid environments. Our research has shown that, contrary to what was previously thought, interflow can be important in semiarid landscapes and is, therefore, an essential consideration for risk assessment in these regions. To illustrate and assess the effect of interflow on estimates of risk, we (1) developed a simple conceptual model to describe the role that interflow may have in the redistribution of surface and near‐surface contamination, and (2) used RESRAD, an exposure model for assessing radionuclide doses to humans, to evaluate the effectiveness of landfill covers in mitigating doses of three contaminants (3H, 238U, and 239/240Pu) at a site in northern New Mexico at which interflow is known to be occurring. Only those calculations of the model that took interflow into account yielded the result that the radionuclides would contaminate groundwater‐underscoring the potential importance of interflow as a mechanism for the transport of contaminants. We conclude that failure to take interflow into account can render risk assessments inaccurate and remediation ineffective. Further, our work demonstrates that a general understanding of hydrological processes is essential for accurate risk assessment, ecological as well as human.  相似文献   

18.
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Aims:  To describe the approach used in conducting a fit‐for‐purpose risk assessment of microbiological human pathogens associated with fresh fruit and the risk management recommendations made. Methods and Results:  A qualitative risk assessment for microbiological hazards in fresh fruit was carried out based on the Codex Alimentarius (Codex) framework, modified to consider multiple hazards and all fresh (whole) fruits. The assessment determines 14 significant bacterial, viral, protozoal and nematodal hazards associated with fresh produce, assesses the probable level of exposure from fresh fruit, concludes on the risk from each hazard, and considers and recommends risk management actions. A review of potential risk management options allowed the comparison of effectiveness with the potential exposure to each hazard. Conclusions:  Washing to a recommended protocol is an appropriate risk management action for the vast majority of consumption events, particularly when good agricultural and hygienic practices are followed and with the addition of refrigerated storage for low acid fruit. Additional safeguards are recommended for aggregate fruits with respect to the risk from protozoa. Significance and Impact of the Study:  The potentially complex process of assessing the risks of multiple hazards in multiple but similar commodities can be simplified in a qualitative assessment approach that employs the Codex methodology.  相似文献   

20.
Access to safe and clean drinking water is an essential element of healthy life also known as the primary human needs. The present study was conducted to investigate heavy metal (HM) concentrations of drinking water. Excess health risk of HM (Cr, Pb, and Cd) intake is related to the drinking water consumption in local population. HMs concentrations were analyzed by using graphite furnace atomic absorption spectrometer and were compared with permissible limits regulated by country and World Health Organization (WHO). The hazard quotient (HQ) and Excess Lifetime Cancer Risk (ELCR) were determined to show the carcinogenic and non-carcinogenic effects of HMs, respectively. HQs were found in the order of Pb > Cd > Cr and subsequently HI index was also estimated for all HM in two age groups (children and adults). The comparisons indicate no possibility of non-carcinogenic effects to the local population. The values for ELCR were found in the order of Cr > Cd > Pb. The ELCR index was found above acceptable risk levels for chromium and cadmium in both children and adults groups. Furthermore, intermetal correlation results revealed that heavy metals have common sources resulting from geogenic and anthropogenic activities and these are major sources of water contamination in Sistan and Baluchestan province.  相似文献   

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