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371.
Results of groundwater and seawater analyses for radioactive ((3)H, (222)Rn, (223)Ra, (224)Ra, (226)Ra, and (228)Ra) and stable (D and (18)O) isotopes are presented together with in situ spatial mapping and time series (222)Rn measurements in seawater, direct seepage measurements using manual and automated seepage meters, pore water investigations using different tracers and piezometric techniques, and geoelectric surveys probing the coast. This study represents first time that such a new complex arsenal of radioactive and non-radioactive tracer techniques and geophysical methods have been used for simultaneous submarine groundwater discharge (SGD) investigations. Large fluctuations of SGD fluxes were observed at sites situated only a few meters apart (from 0cmd(-1) to 360cmd(-1); the unit represents cm(3)/cm(2)/day), as well as during a few hours (from 0cmd(-1) to 110cmd(-1)), strongly depending on the tidal fluctuations. The average SGD flux estimated from continuous (222)Rn measurements is 17+/-10cmd(-1). Integrated coastal SGD flux estimated for the Ubatuba coast using radium isotopes is about 7x10(3)m(3)d(-1) per km of the coast. The isotopic composition (deltaD and delta(18)O) of submarine waters was characterised by significant variability and heavy isotope enrichment, indicating that the contribution of groundwater in submarine waters varied from a small percentage to 20%. However, this contribution with increasing offshore distance became negligible. Automated seepage meters and time series measurements of (222)Rn activity concentration showed a negative correlation between the SGD rates and tidal stage. This is likely caused by sea level changes as tidal effects induce variations of hydraulic gradients. The geoelectric probing and piezometric measurements contributed to better understanding of the spatial distribution of different water masses present along the coast. The radium isotope data showed scattered distributions with offshore distance, which imply that seawater in a complex coast with many small bays and islands was influenced by local currents and groundwater/seawater mixing. This has also been confirmed by a relatively short residence time of 1-2 weeks for water within 25km offshore, as obtained by short-lived radium isotopes. The irregular distribution of SGD seen at Ubatuba is a characteristic of fractured rock aquifers, fed by coastal groundwater and recirculated seawater with small admixtures of groundwater, which is of potential environmental concern and has implications on the management of freshwater resources in the region.  相似文献   
372.
This research was aimed at understanding the dynamics of the herbicides diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], imazapic [2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-5-methylnicotinic acid] and isoxaflutole [5-cyclopropyl-4-(2-methanesulfonyl-4-trifluoromethyl benzoyl)isoxazole] in two soils of different physico-chemical properties. To accomplish such intent, several greenhouse experiments were run. The bioavailability of diuron (0; 1.6 and 3.2 kg ha? 1), imazapic (0; 98 and 122.5 g ha? 1) and isoxaflutole (0; 35 and 70 g ha? 1) was measured in samples from a sandy loam soil and a clay soil, by sowing a bioindicator (Brachiaria decumbens), at 0, 25, 50, 75 and 100 days after herbicides application (DAA). Diuron was very stable in clay soil, providing control equal to or higher than 92% of bioindicator, up to 100 DAA, as assumed by biomass accumulation. No differential effect was observed in sandy loam soil, even when 2x labeled rate were applied. Imazapic provided a short bioavailability in relation to B. decumbens, independent of rates applied. The persistence of isoxaflutole was longer in clay soil (28 to 30 days).  相似文献   
373.

Globally, hepatitis A virus (HAV) is one of the most common agents of acute viral hepatitis and causes approximately 1.4 million cases and 90,000 deaths annually despite the existence of an effective vaccine. In 2019, federal, state, and local partners investigated a multi-state outbreak of HAV infections linked to fresh blackberries sourced from multiple suppliers in Michoacán, Mexico. A total of 20 individuals with outbreak-related HAV infection were reported in seven states, including 11 hospitalizations, and no deaths. The Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and Nebraska State and Douglas County Health Departments conducted a traceback investigation for fresh blackberries reportedly purchased by 16 ill persons. These individuals reported purchasing fresh blackberries from 11 points of service from September 16 through 29, 2019 and their clinical isolates assessed through next-generation sequencing and phylogenetic analysis were genetically similar. The traceback investigation did not reveal convergence on a common grower or packing house within Mexico, but all of the blackberries were harvested from growers in Michoacán, Mexico. FDA did not detect the pathogen after analyzing fresh blackberry samples from four distributors, one consumer, and from nine importers at the port of entry as a result of increased screening. Challenges included gaps in traceability practices and the inability to recover the pathogen from sample testing, which prohibited investigators from determining the source of the implicated blackberries. This multi-state outbreak illustrated the importance of food safety practices for fresh produce that may contribute to foodborne illness outbreaks.

  相似文献   
374.
Summary Intracolony aggression among workers of the neotropical ponerine ant species Pachycondyla apicalis leads to dominance orders. Antagonistic interactions can entail either overt physical attacks with the subordinate individual often exhibiting a submissive posture or the robbing and destruction of eggs laid by nestmates. The single queen, however, was never observed either attacking or being attacked by any colony member. The hierarchical structure among workers consists of one dominant individual and several subordinates; the relationships among subordinate workers are unclear, however. We report for the first time a natural (nonmanipulated) change in the social status of individuals within an ant dominance order. Dominant workers usually had better developed ovaries, laid more eggs and were more frequently observed attending the egg pile than subordinate individuals. This pattern became even more striking when the queen was excluded from the colony. These results indicate that workers of P. apicalis lay eggs even in the presence of the queen. It is possible that some of these haploid eggs may develop into males.Offprint requests to: B. Holldobler  相似文献   
375.
In Venezuela, large-scale shrimp farming began in the 1980s. By 1987, the Ministry of Environment and Natural Resources (MARNR) had received 14 proposals for approval. A developer illegally started the construction of ponds at the Píritu Lagoon in the State of Anzoátegui before the authorization process was completed. This action triggered a land-use conflict. This study identifies the causes for public protest and determines the consequences of this conflict for land-use management. The results show that public protest was based on the impacts of the partial construction of ponds. These impacts were related to direct removal of wetlands, interruption of natural patterns of surface flows, and alteration of feeding grounds of some bird species with migratory status. Consequences were identified in relation to the role that nongovernmental organizations (NGOs) play in land-use conflicts and the actions that MARNR could take in the future to prevent and solve similar situations.  相似文献   
376.
The assembling of a system for field sampling and activity concentration measurement of radon dissolved in groundwater is described. Special attention is given in presenting the calibration procedure to obtain the radon activity concentration in groundwater from the raw counting rate registered in a portable scintillation detector and in establishing the precision of the activity concentration measurements. A field procedure was established and the system tested during one year of monthly observations of 222Rn activity concentration in groundwater drawn from two wells drilled on metamorphic rocks exposed at Eastern São Paulo State, Brazil. The observed mean 222Rn activity concentrations are 374 Bq/dm3 in one well and about 1275 Bq/dm3 in the other one. In both wells the 222Rn activity concentrations showed a seasonal variation similar to variations previously reported in the literature for the same region.  相似文献   
377.
Noroviruses are the major cause of non-bacterial acute gastroenteritis outbreaks in humans, with few reports about the occurrence of the norovirus GIV strain. We investigated the presence of norovirus GIV in surface water (river, bay, and stream) and untreated sewage, and we determined a positivity rate of 9.4 % (9/96). The strains genotyped were GIV.1. To our knowledge, this is the first report of GIV in Brazil.  相似文献   
378.
379.
The subject of sustainability reports, especially those related to GRI, has become an interesting topic to academics and practitioners. This paper seeks to propose an easy-to-use sustainability reporting assessment tool that is suitable to the GRI G4 guidelines. Our idea is to provide a tool that can be applied by an organization, based in GRI indicators, in a quick and easy way. The tool, called G-Index, represents the organizational sustainability performance. The index is a sum of four factors, and a questionnaire about the GRI elements raised the data to elaborate a Mudge diagram, which was used to define the weight values. Finally, the method for the evaluation tool was established, and a case study with the automotive sector was performed. The results showed us the G-Index represents a good option to assess the organization’s disclosure practices in sustainability reports based on the GRI framework. The report analysis presented some important facts, it is more common the disclosure of the Management Approach then the application of External Assurance. Furthermore, even the General Standard Disclosures of the GRI guidelines being mandatory, some companies do not fully disclose them, as shown in the GS factor, that makes up, the G-Index.  相似文献   
380.
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