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961.
The current experiment was conducted to evaluate the effects of feeding dried sweet orange peel (SOP) and lemon grass leaves (LGL) as feed additives on broiler growth performance, serum metabolites, and antioxidant status. A total of 192-day-old (Ross 308) broiler chickens were distributed randomly into 4 dietary treatments with 4 replicates per each treatment. The dietary treatments included a control diet without any feed additive (T1), a diet containing 0.8 % SOP (T2), a diet containing 0.8 % LGL (T3), and a diet containing combination of 0.4 % SOP?+?0.4 % LGL (T4) was fed during the growth period from 22 to 42 days. Feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), carcass traits, serum components, and antioxidant status were measured. At the end of the experimental period, the results indicated that supplementation of SOP and LGL alone or in combination did not significantly (P?>?0.05) affect BWG, FI, FCR, and carcass characteristics in broiler chickens. Serum total protein was increased significantly (P?<?0.05) in T3 and T4 compared to the other treatments. Also, serum globulin increased significantly (P?<?0.05) in the treated groups. Serum glucose, low density lipoprotein, triglyceride, and very low density lipoprotein decreased significantly (P?<?0.05) in the treatment groups, while cholesterol and high-density lipoprotein decreased in T2 compared to the other groups. Significantly (P?<?0.05) higher total antioxidant status was observed in T2 compared to the other treatments. In conclusion, these results indicate that SOP, LGL, and their combination may positively modify some serum components and the antioxidant status without any beneficial effect on growth performance and carcass traits in broiler chickens.  相似文献   
962.
The main objectives of this work were to identify and determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) and trace metals in carpet dust samples from various mosques of the city of Riyadh and to assess the health risks associated with the exposure to these pollutants. Therefore, 31 samples of mosque’s carpet dust from Riyadh were collected. The results showed that 14 PAHs were present in the dust samples with concentrations ranged from 90 to 22,146 ng g?1 (mean = 4096 ± 4277 ng g?1) where low molecular weight compounds were dominant. The presence of PAHs were in the order of naphthalene > chrysene and benzo(b)fluoranthene > benzo(a)pyrene > acenaphthene and benzo(k)fluoranthene > pyrene and the absence of indeno(1,2,3-cd)pyrene and dibenz(a,h)anthracene. The diagnostic ratio coupled with principle component analysis (PCA) revealed mix sources of petrogenic from traffic, stack emission, and pyrogenic inputs from essence and perfumed wood burning. Trace metals were significant in the dust samples, and their concentrations decrease in the order of Zn, Mn, Cu, Cr, Pb, Ni, and V where Zn being the highest (94.4 ± 91.5 μg g?1) and indium was the lowest (1.9 ± 9.3 μg g?1). The trace metals were major in southern and central parts of Riyadh and followed the order of central Riyadh > southern Riyadh > western Riyadh > eastern Riyadh > northern Riyadh. Estimated risk based on the total PAHs was found to be 4.30 × 10?11 for adult and 1.56 × 10?11 for children. Elemental non-cancer risk for adults ranged from 7.9 × 10?4 for Co to 7.58 × 10?1 for Li and for children ranged from 3.70 × 10?3 for Co to 3.54 for Li. Policy implication and mitigations of PAHs in Riyadh and Saudi Arabia were highlighted.  相似文献   
963.
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations.  相似文献   
964.
The Bio-response Operational Testing and Evaluation (BOTE) Project was a cross-government effort designed to operationally test and evaluate a response to a biological incident (release of Bacillus anthracis [Ba] spores, the causative agent for anthrax) from initial public health and law enforcement response through environmental remediation. The BOTE Project was designed to address site remediation after the release of a Ba simulant, Bacillus atrophaeus spp. globigii (Bg), within a facility, drawing upon recent advances in the biological sampling and decontamination areas. A key component of response to a biological contamination incident is the proper management of wastes and residues, which is woven throughout all response activities. Waste is generated throughout the response and includes items like sampling media packaging materials, discarded personal protective equipment, items removed from the facility either prior to or following decontamination, aqueous waste streams, and materials generated through the application of decontamination technologies. The amount of residual contaminating agent will impact the available disposal pathways and waste management costs. Waste management is an integral part of the decontamination process and should be included through “Pre-Incident” response planning. Overall, the pH-adjusted bleach decontamination process generated the most waste from the decontamination efforts, and fumigation with chlorine dioxide generated the least waste. A majority of the solid waste generated during pH-adjusted bleach decontamination was the nonporous surfaces that were removed, bagged, decontaminated ex situ, and treated as waste. The waste during the two fumigation rounds of the BOTE Project was associated mainly with sampling activities. Waste management activities may represent a significant contribution to the overall cost of the response/recovery operation. This paper addresses the waste management activities for the BOTE field test.Implications: Management of waste is a critical element of activities dealing with remediation of buildings and outdoor areas following a biological contamination incident. Waste management must be integrated into the overall remediation process, along with sampling, decontamination, resource management, and other important response elements, rather than being a stand-alone activity. The results presented in this paper will provide decision makers and emergency planners at the federal/state/tribal/local level information that can be used to integrate waste management into an overall systems approach to planning and response activities.  相似文献   
965.
Nitrogen (N) availability plays multiple roles in the boreal landscape, as a limiting nutrient to forest growth, determinant of terrestrial biodiversity, and agent of eutrophication in aquatic ecosystems. We review existing research on forest N dynamics in northern landscapes and address the effects of management and environmental change on internal cycling and export. Current research foci include resolving the nutritional importance of different N forms to trees and establishing how tree–mycorrhizal relationships influence N limitation. In addition, understanding how forest responses to external N inputs are mediated by above- and belowground ecosystem compartments remains an important challenge. Finally, forestry generates a mosaic of successional patches in managed forest landscapes, with differing levels of N input, biological demand, and hydrological loss. The balance among these processes influences the temporal patterns of stream water chemistry and the long-term viability of forest growth. Ultimately, managing forests to keep pace with increasing demands for biomass production, while minimizing environmental degradation, will require multi-scale and interdisciplinary perspectives on landscape N dynamics.  相似文献   
966.

The risk of cancer due to PCB exposure in humans is highly debated. In eastern Slovakia, high exposure of the population to organochlorines (especially PCBs) was associated with various disease and disorder pathways, viz., endocrine disruption, metabolic disorder & diabetes, and cancer, thereby disturbing several cellular processes, including protein synthesis, stress response, and apoptosis. We have evaluated a Slovak cohort (45-month children, at lower and higher levels of PCB exposure from the environment) for disease and disorder development to develop early disease cancer biomarkers that could shed new light on possible mechanisms for the genesis of cancers under such chemical exposures, and identify potential avenues for prevention.

Microarray studies of global gene expression were conducted from the 45-month-old children on the Affymetrix platform followed by Ingenuity Pathway Analysis (IPA®) to associate the affected genes with their mechanistic pathways. High-throughput qRT-PCR TaqMan low-density array (TLDA) was performed to further validate the selected genes on the whole blood cells of the most highly exposed children from the study cohort (n = 71).

TP53, MYC, BCL2, and LRP12 differential gene expressions suggested strong relationships between potential future tumor promotion and PCB exposure in Slovak children. The IPA analysis further detected the most important signaling pathways, including molecular mechanism of cancers, prostate cancer signaling, ovarian cancer signaling, P53 signaling, oncostatin M signaling, and their respective functions (viz., prostate cancer, breast cancer, progression of tumor, growth of tumor, and non-Hodgkin’s disease). The results suggest that PCB exposures, even at the early age of these children, may have lifelong consequences for the future development of chronic diseases.

  相似文献   
967.
Drought is a significant natural hazard that slowly evolves over time. Because of its character, drought is difficult to monitor and impacts are often poorly documented. Agriculture is one of the most sensitive sectors that are prone to drought. The objective of this research is to assess the impacts of drought on soybean production and revenue in Kentucky. Soybeans are one of Kentucky’s most important commodities. In this study, impacts of 1930–1931, 1940–1942, 1952–1955, 1987–1988, 1999–2000, and 2007 droughts were considered. It was found that over the recent years, up to 56 % of the revenue from soybeans was lost due to drought. During the first half of the twentieth century, revenue loss reached up to 77 %. This research is valuable to the general public as well as planners and policy makers. Proper documentation of impacts of past droughts will help identify drought vulnerabilities and results in better risk management and mitigation.  相似文献   
968.

Rock ptarmigan (Lagopus muta) and willow ptarmigan (L. lagopus) are Arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. Here, we compiled information from 90 ptarmigan study sites from 7 Arctic countries, where almost half of the sites are still monitored. Rock ptarmigan showed an overall negative trend on Iceland and Greenland, while Svalbard and Newfoundland had positive trends, and no significant trends in Alaska. For willow ptarmigan, there was a negative trend in mid-Sweden and eastern Russia, while northern Fennoscandia, North America and Newfoundland had no significant trends. Both species displayed some periods with population cycles (short 3–6 years and long 9–12 years), but cyclicity changed through time for both species. We propose that simple, cost-efficient systematic surveys that capture the main feature of ptarmigan population dynamics can form the basis for citizen science efforts in order to fill knowledge gaps for the many regions that lack systematic ptarmigan monitoring programs.

  相似文献   
969.
Lidström  Susanna  Sörlin  Sverker  Svedäng  Henrik 《Ambio》2020,49(5):1114-1121
Ambio - Before the mid-twentieth century, there was no comprehensive narrative about empirical conditions in Swedish seas. Around 1970, this view changed profoundly. In line with growing research...  相似文献   
970.
Abstract

The goal of the Regional Haze Rule (RHR) is to return visibility in class I areas (CIAs) to natural levels, excluding weather-related events, by 2064. Whereas visibility, the seeing of scenic vistas, is a near instantaneous and sight-path-dependent phenomenon, reasonable progress toward the RHR goal is assessed by tracking the incremental changes in 5-yr average visibility. Visibility is assessed using a haze metric estimated from 24-hr average aerosol measurements that are made at one location representative of the CIA. It is assumed that, over the 5-yr average, the aerosol loadings and relative humidity along all of the site paths are the same and can be estimated from the 24-hr measurements. It is further assumed that any time a site path may be obscured by weather (e.g., clouds and precipitation), there are other site paths within the CIA that are not. Therefore, when calculating the haze metric, sampling days are not filtered for weather conditions. This assumption was tested by examining precipitation data from multiple monitors for four CIAs. It is shown that, in general, precipitation did not concurrently occur at all monitors for a CIA, and precipitation typically occurred 3-8 hr or less in a day. In a recent paper in this journal, Ryan asserts that the haze metric should include contributions from precipitation and conducted a quantitative assessment incorrectly based on the assumption that the Optec NGN-2 nephelometer measurements include the effects of precipitation. However, these instruments are programmed to shut down during rain events, and any data logged are in error. He further assumes that precipitation occurs as often on the haziest days as the clearest days and that precipitation light scattering (bprecip) is independent of geographic location and applied an average bprecip derived for Great Smoky Mountains to diverse locations including the Grand Canyon. Both of these assumptions are shown to be in error.  相似文献   
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