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61.
A variety of seals is used to close bags. Each seal has advantages and disadvantages. For shop assistants sealing bags could be a repetitive physically demanding action. Opening and closing the bags again can cause some discomfort or annoyance for consumers. Besides, it is an activity which can endanger safety, i.e., knives being used in opening, children swallowing the systems of sealing. To prevent these problems a new sealing system was developed. In this paper the opinion of shop assistants, consumers and experts on several bag sealing systems was studied. It appeared that for sealing plastic bags, adhesive tape with paper is the best out of 4 systems, closely followed by adhesive tape. It is discussed that for the elderly, there is still room for improvement in opening bag seals.  相似文献   
62.
This review of the literature on environmental auditing and the potential role of accountants distinguishes between compliance audits and audits of the environmental management system. After an extensive introduction to the concept, this review focuses on the similarities and differences between an environmental audit and a financial statement audit. The general approach to both types of audits is similar, except that environmental audits are largely unregulated. Both audits place an emphasis on the evaluation of control systems, which is an argument in favor of external auditors playing a role in environmental audits. Another argument for including external accountants is their code of ethics. However, these professionals seem to be reluctant to enter the field of environmental auditing. It is argued that this reluctance is because of a lack of generally accepted principles for conducting environmental audits. If external accountants are engaged in environmental auditing, they should be part of multidisciplinary teams that also include scientists and engineers to avoid a too strong focus on procedures. Rather than treating these audits as totally different, it is proposed that there be a move towards integrated, or even universal, audits.  相似文献   
63.
Sustainable development goals are achievable through the installation of Material Recovery Facilities (MRFs) in certain solid waste management systems, especially those in rapidly expanding multi-district urban areas. MRFs are a cost-effective alternative when curbside recycling does not demonstrate long-term success. Previous capacity planning uses mixed integer programming optimization for the urban center of the city of San Antonio, Texas to establish that a publicly owned material recovery facility is preferable to a privatized facility. As a companion study, this analysis demonstrates that a MRF alleviates economic, political, and social pressures facing solid waste management under uncertainty. It explores the impact of uncertainty in decision alternatives in an urban environmental system. From this unique angle, waste generation, incidence of recyclables in the waste stream, routing distances, recycling participation, and other planning components are taken as intervals to expand upon previous deterministic integer-programming models. The information incorporated into the optimization objectives includes economic impacts for recycling income and cost components in waste management. The constraint set consists of mass balance, capacity limitation, recycling limitation, scale economy, conditionality, and relevant screening restrictions. Due to the fragmented data set, a grey integer programming modeling approach quantifies the consequences of inexact information as it propagates through the final solutions in the optimization process. The grey algorithm screens optimal shipping patterns and an ideal MRF location and capacity. Two case settings compare MRF selection policies where optimal solutions exemplify the value of grey programming in the context of integrated solid waste management.  相似文献   
64.
65.
Two plant species, arugula (Eruca sativa) and mustard (Brassica juncea) were field-grown under four soil management practices: soil mixed with municipal sewage sludge (SS), soil mixed with horse manure (HM), soil mixed with chicken manure (CM), and no-mulch bare soil (NM) to investigate the impact of soil amendments on the concentration of glucosinolates (GSLs) in their shoots. GSLs, hydrophilic plant secondary metabolites in arugula and mustard were extracted using boiling methanol and separated by adsorption on sephadex ion exchange disposable pipette tips filled with DEAE, a weak base, with a net positive charge that exchange anions such as GSLs. Quantification of GSLs was based on inactivation of arugula and mustard myrosinase and liberation of the glucose moiety from the GSLs molecule by addition of standardized myrosinase (thioglucosidase) and spectrophotometric quantification of the liberated glucose moiety. Overall, GSLs concentrations were significantly greater (1287 µg g?1 fresh shoots) in plants grown in SS compared to 929, 890, and 981 µg g?1 fresh shoots in plants grown in CM, HM, and NM soil, respectively. Results also revealed that mustard shoots contained greater concentrations of GSLs (974 µg g?1 fresh shoots) compared to arugula (651 µg g?1 fresh shoots).  相似文献   
66.
Selective agrochemicals including herbicides that do not affect non-target organisms such as natural enemies are important in the integrated pest management (IPM) programs. The aim of this study was to evaluate the herbicide toxicity, selectivity and hormesis of nicosulfuron, recommended for the corn Zea mays L. (Poaceae) crop, on 10 Trichogrammatidae (Hymenoptera) species. A female of each Trichogramma spp. or Trichogrammatoidea annulata De Santis, 1972 was individually placed in plastic test tubes (no choice) with a cardboard containing 45 flour moth Anagasta ( = Ephestia) kuehniella Zeller, 1879 (Lepidoptera: Pyralidae) eggs. Parasitism by these natural enemies was allowed for 48 h and the cardboards were sprayed with the herbicide nicosulfuron at 1.50 L.ha?1, along with the control (only distilled water). Nicosulfuron reduced the emergence rate of Trichogramma bruni Nagaraja, 1983 females, but increased that of Trichogramma pretiosum Riley, 1879, Trichogramma acacioi Brun, Moraes and Smith, 1984 and T. annulata females. Conversely, this herbicide increased the emergence rate of Trichogramma brasiliensis Ashmead, 1904, T. bruni, Trichogramma galloi Zucchi, 1988 and Trichogramma soaresi Nagaraja, 1983 males and decreased those of T. acacioi, Trichogramma atopovilia Oatman and Platner, 1983 and T. pretiosum males. In addition, nicosulfuron reduced the sex ratio of T. galloi, Trichogramma bennetti Nagaraja and Nagarkatti, 1973 and T. pretiosum and increased that of T. acacioi, T. bruni, T. annulata, Trichogramma demoraesi Nagaraja, 1983, T. soaresi and T. brasiliensis. The herbicide nicosulfuron was “harmless” (class 1, <30% reduction) for females and the sex ratio of all Trichogrammatidae species based on the International Organization for Biological Control (IOBC) classification. The possible hormesis effect of nicosulfuron on Trichogrammatidae species and on the bacterium Wolbachia sp. (Rickettsiales: Rickettsiaceae) was also discussed.  相似文献   
67.
Natural resource and wildlife managers must balance the disparate priorities of a diversity of stakeholders. To manage these priorities, a firm understanding of topics salient to the public is needed. The media often report on issues of importance to the public; therefore, these reports may be a useful measure of public interest. However, efficient methods for distinguishing diverse topics related to a wildlife management issue reported in the media and changes in the salience of those topics have been lacking. We used latent Dirichlet allocation, a Bayesian mixture model, to quantitatively assess the salience of topics surrounding the gray wolf (Canis lupus), which was reintroduced to Idaho (U.S.A.) in 1995. We analyzed articles published from 1960 to 2015 in an Idaho newspaper. We identified 6 distinct topics associated with gray wolves: policy, hunting, biological status, implementation of management, recovery, and human-wolf conflict. The salience of topics pre- and postreintroduction of wolves (1995) and pre- and postdelisting of wolves from the U.S. Endangered Species Act (2009) differed significantly, underscoring that these events were turning points in how issues were being publicly discussed and framed. Articles written by the local reporters were more likely to report on topics regarding conflict between humans and wolves, whereas articles sourced from a national outlet reported more on topics pertaining to wolf policy and biological status. In the context of managing a contentious, far-ranging, and long-lived wildlife species, our methods can help guide the location and timing of a suite of management strategies (e.g., media relation plans and stakeholder engagement) that promote human-wildlife coexistence across different landscapes.  相似文献   
68.
Invasive rats are one of the world's most successful animal groups that cause native species extinctions and ecosystem change, particularly on islands. On large islands, rat eradication is often impossible and population control, defined as the local limitation of rat abundance, is now routinely performed on many of the world's islands as an alternative management tool. However, a synthesis of the motivations, techniques, costs, and outcomes of such rat‐control projects is lacking. We reviewed the literature, searched relevant websites, and conducted a survey via a questionnaire to synthesize the available information on rat‐control projects in island natural areas worldwide to improve rat management and native species conservation. Data were collected from 136 projects conducted over the last 40 years; most were located in Australasia (46%) and the tropical Pacific (25%) in forest ecosystems (65%) and coastal strands (22%). Most of the projects targeted Rattus rattus and most (82%) were aimed at protecting birds and endangered ecosystems. Poisoning (35%) and a combination of trapping and poisoning (42%) were the most common methods. Poisoning allows for treatment of larger areas, and poison projects generally last longer than trapping projects. Second‐generation anticoagulants (mainly brodifacoum and bromadiolone) were used most often. The median annual cost for rat‐control projects was US$17,262 or US$227/ha. Median project duration was 4 years. For 58% of the projects, rat population reduction was reported, and 51% of projects showed evidence of positive effects on biodiversity. Our data were from few countries, revealing the need to expand rat‐control distribution especially in some biodiversity hotspots. Improvement in control methods is needed as is regular monitoring to assess short‐ and long‐term effectiveness of rat‐control.  相似文献   
69.

In tropical areas, pioneer occupation fronts steer the rapid expansion of deforestation, contributing to carbon emissions. Up-to-date carbon emission estimates covering the long-term development of such frontiers depend on the availability of high spatial–temporal resolution data. In this paper, we provide a detailed assessment of carbon losses from deforestation and potential forest degradation from fragmentation for one expanding frontier in the Brazilian Amazon. We focused on one of the Amazonia’s hot-spots of forest loss, the BR-163 highway that connects the high productivity agricultural landscapes in Mato Grosso with the exporting harbors of the Amazon. We used multi-decadal (1984–2012) Landsat-based time series on forested and non-forested area in combination with a carbon book-keeping model. We show a 36% reduction in 1984s biomass carbon stocks, which led to the emission of 611.5 TgCO2 between 1985 and 1998 (43.6 TgCO2 year−1) and 959.8 TgCO2 over 1999–2012 (68.5 TgCO2 year−1). Overall, fragmentation-related carbon losses represented 1.88% of total emissions by 2012, with an increasing relevance since 2004. We compared the Brazilian Space Agency deforestation assessment (PRODES) with our data and found that small deforestation polygons not captured by PRODES had increasing importance on estimated deforestation carbon losses since 2000. The comparative analysis improved the understanding of data-source-related uncertainties on carbon estimates and indicated disagreement areas between datasets that could be subject of future research. Furthermore, spatially explicit, annual deforestation and emission estimates like the ones derived from this study are important for setting regional baselines for REDD+ or similar payment for ecosystem services frameworks.

  相似文献   
70.
Abstract

The presence of diethyl-phthalate (DEP), dibutyl-phthalate (DBP), butylbenzyl-phthalate (BBP), diethylhexyl-phthalate (DEHP) and diisononyl-phthalate (DINP) was determined in 295 tequila samples. They were grouped by age of maturation (white, aged, extra aged or ultra aged) and year of production (between 2013 and 2018). Gas Chromatography coupled with Mass Spectrometry was used for identification and quantification. The results showed that 65 samples (22% of the total) were phthalate free. DEP (0.13-0.27?mg/kg), BBP (0.05–2.91?mg/kg) and DINP (1.64–3.43?mg/kg) were detected in 11 (3.73%), 37 (12.54%) and 5 (1.69%) samples, respectively. But, these concentrations did not exceed the maximum permitted limits (MPL) of phthalates for alcoholic beverages. DBP (0.01–2.20?mg/kg) and DEHP (0.03–4.64?mg/kg) were detected in 96 (32.54%) and 224 (75.93%) samples, from them only 10 (3.39%) and 15 (5.08%) samples, respectively, exceeded the MPL for alcoholic beverages and they were few tequilas produced in the year 2014 or before. DEHP was the most frequent phthalate found in tequila and observed DEHP concentrations were 2-times higher in ultra aged tequilas compared to those in white tequilas. We concluded that all tequilas produced in 2015 and after, satisfied the international standards for these compounds.  相似文献   
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