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91.
Phanogenia gracilis sensu lato is a shallow-water crinoid distributed throughout the Indo-western Pacific. The taxonomy of P. gracilis s.l. is clouded by the presence of two distinct morphotypes, each differing in morphology and ecology. The goal was to determine the taxonomic status of P. gracilis s.l. using partial gene sequences of two mitochondrial DNA genes, cytochrome oxidase c subunit I and NADH dehydrogenase subunit II, in conjunction with morphological and ecological data. The molecular phylogenies revealed three lineages separated by 5.0–6.6% corrected genetic distance, which is consistent with the genetic distances among other echinoderm species. Neither morphotype was monophyletic, nor was any examined morphological character exclusive to any one lineage. Discriminant function analysis (DFA) of the morphological and ecological data yielded significant results when grouping P. gracilis by morphotype and by clades recovered in the phylogenetic analyses, but grouping by sample locality was rejected. Although DFA results of grouping by clade were significant, jackknife support was weak, while only correctly grouping specimens by their respective clades 65% of the time. The results suggest the possibility of cryptic species, but additional molecular and morphological data are needed to confirm this. This study demonstrates the need to reevaluate the taxonomy of crinoid species and their respective diagnostic characters.  相似文献   
92.
Parental care is an energetically demanding activity that ensures genes are efficiently passed from one generation to the next. According to evolutionary theory, the greatest energetic investment should be directed towards offspring that are most closely related to the parent. Male fathead minnows, Pimephales promelas, provide this parental investment to developing embryos but not newly hatched larvae. Therefore, selection should favour recognition of embryonic kin to ensure energetic expenditure is optimally invested. In this study, adult male fathead minnows were tested using behavioural assays, with egg cannibalism as an endpoint, to determine whether adult males could discriminate between related and unrelated embryos. Egg cannibalism was highest when adult male fathead minnows were presented with unrelated eggs and lowest when presented with eggs fertilized by the test subject (related eggs). The degree of cannibalism was also a function of breeding status. Unrelated males in breeding condition showed an intermediate response between the low cannibalism demonstrated by related males and the high cannibalism demonstrated by unrelated males in a nonbreeding condition. These results suggest that although male fathead minnows can discriminate between unrelated and related embryos, at least some component of parental investment is a simple function of breeding status.  相似文献   
93.
Electricity network investment and asset management require accurate estimation of future demand in energy consumption within specified service areas. For this purpose, simple models are typically developed to predict future trends in electricity consumption using various methods and assumptions. This paper presents a statistical model to predict electricity consumption in the residential sector at the Census Collection District (CCD) level over the state of New South Wales, Australia, based on spatial building and household characteristics. Residential household demographic and building data from the Australian Bureau of Statistics (ABS) and actual electricity consumption data from electricity companies are merged for 74 % of the 12,000 CCDs in the state. Eighty percent of the merged dataset is randomly set aside to establish the model using regression analysis, and the remaining 20 % is used to independently test the accuracy of model prediction against actual consumption. In 90 % of the cases, the predicted consumption is shown to be within 5 kWh per dwelling per day from actual values, with an overall state accuracy of ?1.15 %. Given a future scenario with a shift in climate zone and a growth in population, the model is used to identify the geographical or service areas that are most likely to have increased electricity consumption. Such geographical representation can be of great benefit when assessing alternatives to the centralised generation of energy; having such a model gives a quantifiable method to selecting the ‘most’ appropriate system when a review or upgrade of the network infrastructure is required.  相似文献   
94.
Citizen science has generated a growing interest among scientists and community groups, and citizen science programs have been created specifically for conservation. We examined collaborative science, a highly interactive form of citizen science, which we developed within a theoretically informed framework. In this essay, we focused on 2 aspects of our framework: social learning and adaptive management. Social learning, in contrast to individual‐based learning, stresses collaborative and generative insight making and is well‐suited for adaptive management. Adaptive‐management integrates feedback loops that are informed by what is learned and is guided by iterative decision making. Participants engaged in citizen science are able to add to what they are learning through primary data collection, which can result in the real‐time information that is often necessary for conservation. Our work is particularly timely because research publications consistently report a lack of established frameworks and evaluation plans to address the extent of conservation outcomes in citizen science. To illustrate how our framework supports conservation through citizen science, we examined how 2 programs enacted our collaborative science framework. Further, we inspected preliminary conservation outcomes of our case‐study programs. These programs, despite their recent implementation, are demonstrating promise with regard to positive conservation outcomes. To date, they are independently earning funds to support research, earning buy‐in from local partners to engage in experimentation, and, in the absence of leading scientists, are collecting data to test ideas. We argue that this success is due to citizen scientists being organized around local issues and engaging in iterative, collaborative, and adaptive learning.  相似文献   
95.
Tourism and hunting both generate substantial revenues for communities and private operators in Africa, but few studies have quantitatively examined the trade‐offs and synergies that may result from these two activities. We evaluated financial and in‐kind benefit streams from tourism and hunting on 77 communal conservancies in Namibia from 1998 to 2013, where community‐based wildlife conservation has been promoted as a land‐use that complements traditional subsistence agriculture. We used data collected annually for all communal conservancies to characterize whether benefits were derived from hunting or tourism. We classified these benefits into 3 broad classes and examined how benefits flowed to stakeholders within communities under the status quo and under a simulated ban on hunting. Across all conservancies, total benefits from hunting and tourism increased at roughly the same rate, although conservancies typically started generating benefits from hunting within 3 years of formation as opposed to after 6 years for tourism. Disaggregation of data revealed that the main benefits from hunting were income for conservancy management and food in the form of meat for the community at large. The majority of tourism benefits were salaried jobs at lodges. A simulated ban on trophy hunting significantly reduced the number of conservancies that could cover their operating costs, whereas eliminating income from tourism did not have as severe an effect. Given that the benefits generated from hunting and tourism typically begin at different times in a conservancy's life‐span (earlier vs. later, respectively) and flow to different segments of local communities, these 2 activities together may provide the greatest incentives for conservation on communal lands in Namibia. A singular focus on either hunting or tourism would reduce the value of wildlife as a competitive land‐use option and have grave repercussions for the viability of community‐based conservation efforts in Namibia, and possibly other parts of Africa.  相似文献   
96.
Community‐based conservation programs in developing countries are often based on the assumption that heteronomous motivation (e.g., extrinsic incentives such as economic rewards and pressure or coercion to act) will incite local communities to adopt conservation behaviors. However, this may not be as effective or sustainable as autonomous motivations (e.g., an intrinsic desire to act due to inherent enjoyment or self‐identification with a behavior and through freedom of choice). We analyzed the comparative effectiveness of heteronomous versus autonomous approaches to community‐based conservation programs through a case study of Sumatran orangutan (Pongo abelii) conservation in 3 villages in Indonesia. Each village had a different conservation program design. We surveyed people (n = 240) to determine their motivations for and behavior changes relative to orangutan and orangutan habitat (forest) protection. Heteronomous motivations (e.g., income from tourism) led to greater self‐reporting of behavior change toward orangutan protection. However, they did not change self‐reported behavior toward forest (i.e., orangutan habitat) protection. The most effective approach to creating self‐reported behavior change throughout the community was a combination of autonomous and heteronomous motivations. Individuals who were heteronomously motivated to protect the orangutan were more likely to have changed attitudes than to have changed their self‐reported behavior. These findings demonstrate that the current paradigm of motivating communities in developing countries to adopt conservation behaviors primarily through monetary incentives and rewards should consider integrating autonomous motivational techniques that promote the intrinsic values of conservation. Such a combination has a greater potential to achieve sustainable and cost‐effective conservation outcomes. Our results highlight the importance of using in‐depth sociopsychological analyses to inform the design and implementation of community‐based conservation programs.  相似文献   
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Steam gasification of two different refuse derived fuels (RDFs), differing slightly in composition as well as thermal stability, was carried out in a fixed-bed reactor at atmospheric pressure. The proximate and ultimate analyses reveal that carbon and hydrogen are the major components in RDFs. The thermal analysis indicates the presence of cellulose and plastic based materials in RDFs. H2 and CO are found to be the major products, along with CO2 and hydrocarbons resulting from gasification of RDFs. The effect of gasification temperature on H2 and CO selectivities was studied, and the optimum temperature for better H2 and CO selectivity was determined to be 725 degrees C. The calorific value of product gas produced at lower gasification temperature is significantly higher than that of gas produced at higher process temperature. Also, the composition of RDF plays an important role in distribution of products gas. The RDF with more C and H content is found to produce more amounts of CO and H2 under similar experimental conditions. The steam/waste ratio showed a notable effect on the selectivity of syngas as well as calorific value of the resulting product gas. The flow rate of carrier gas did not show any significant effect on products yield or their distribution.  相似文献   
100.
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