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421.
Joseph C. Spagna Adam Schelkopf Tiana Carrillo Andrew V. Suarez 《Die Naturwissenschaften》2009,96(2):243-250
Evolutionary co-option of existing structures for new functions is a powerful yet understudied mechanism for generating novelty.
Trap-jaw ants of the predatory genus Odontomachus are capable of some of the fastest self-propelled appendage movements ever recorded; their devastating strikes are not only
used to disable and capture prey, but produce enough force to launch the ants into the air. We tested four Odontomachus species in a variety of behavioral contexts to examine if their mandibles have been co-opted for an escape mechanism through
ballistic propulsion. We found that nest proximity makes no difference in interactions with prey, but that prey size has a
strong influence on the suite of behaviors employed by the ants. In trials involving a potential threat (another trap-jaw
ant species), vertical jumps were significantly more common in ants acting as intruders than in residents (i.e. a dangerous
context), while horizontal jumps occurred at the same rate in both contexts. Additionally, horizontal jump trajectories were
heavily influenced by the angle at which the substrate was struck and appear to be under little control by the ant. We conclude
that while horizontal jumps may be accidental side-effects of strikes against hard surfaces, vertical escape jumps are likely
intentional defensive behaviors that have been co-opted from the original prey-gathering and food-processing functions of
Odontomachus jaws. 相似文献
422.
Adam S. Markowski M. Sam Mannan Agata Kotynia Henryk Pawlak 《Journal of Loss Prevention in the Process Industries》2011,24(6):780-790
Safety and health of workers potentially being at risk from explosive atmospheres are regulated by separate regulations (ANSI/AIHA in USA and ATEX in the European Union). The ANSI/AIHA does not require risk assessment whereas it is compulsory for ATEX. There is no standard method to do that assessment. For that purpose we have applied the explosion Layer of Protection Analysis (ExLOPA), which enables semi-quantitative risk assessment for process plants where explosive atmospheres occur. The ExLOPA is based on the original work of CCPS for LOPA taking into account an explosion accident scenario at workplace. That includes typical variables appropriate for workplace explosion like occurrence of the explosive atmosphere, the presence of effective ignition sources, activity of the explosion prevention and mitigation independent protection layers as well as the severity of consequences. All those variables are expressed in the form of qualitative linguistic categories and relations between them are presented using expert based engineering knowledge, expressed in the form of appropriate set of rules. In this way the category of explosion risk may be estimated by the semi-quantitative analysis. However, this simplified method is connected with essential uncertainties providing over or under estimation of the explosion risk and may not provide real output data.In order to overcome this problem and receive more detailed quantitative results, the fuzzy logic system was applied. In the first stage called fuzzification, all linguistic categories of the variables are mapped by fuzzy sets. In the second stage, the number of relation between all variables of analysis are determined by the enumerative combinatorics and the set of the 810 fuzzy rules “IF-THEN” is received. Each rule enables determination of the fuzzy risk level for a particular accident scenario. In the last stage, called defuzzification, the crisp value of final risk is obtained using a centroid method. The final result of the risk presents a contribution of each risk category represented by the fuzzy sets (A, TA, TNA and NA) and is therefore more precise and readable than the traditional approach producing one category of risk only. Fuzzy logic gives a possibility of better insights into hazards and safety phenomena for each explosion risk scenario. It is not possible to receive such conclusions from the traditional ExLOPA calculation results. However it requires the application of computer-aided analyses which may be partially in conflict with a simplicity of ExLOPA.The practical example provides a comparison between the traditional results obtained by ExLOPA and by fuzzy ExLOPA methods. 相似文献
423.
Merrington Graham Peters Adam Wilson Iain Cooper Chris Van Assche Frank Ryan Adam 《Environmental science and pollution research international》2021,28(2):1789-1800
Environmental Science and Pollution Research - National Environmental Quality Standards (EQS) for zinc used for the assessment of ecological status in freshwaters have been shown to vary by over... 相似文献
424.
Caitlin A. Grady Adam P. Reimer Jane Frankenberger Linda Stalker Prokopy 《Journal of the American Water Resources Association》2013,49(4):883-895
There is an increasing need to document the impacts of conservation‐related best management practices (BMPs) on water quality within a watershed. However, this impact analysis depends upon accurate geospatial locations of existing practices, which are difficult to obtain. This study demonstrates and evaluates three different methods for obtaining geospatial information for BMPs. This study was focused on the Eagle Creek Watershed, a mixed use watershed in central Indiana. We obtained geospatial information for BMPs through government records, producer interviews, and remote‐sensing aerial photo interpretation. Aerial photos were also used to validate the government records and producer interviews. This study shows the variation in results obtained from the three sources of information as well as the benefits and drawbacks of each method. Using only one method for obtaining BMP information can be incomplete, and this study demonstrates how multiple methods can be used for the most accurate picture. 相似文献
425.
Galadima Mukhtar Danladi Aminu Abubakar Wambai Adam Ibrahim Muhammad Adamu Ibrahim Mohammed Suleiman Hassan Hassan 《Environmental science and pollution research international》2022,29(35):52818-52832
Environmental Science and Pollution Research - This paper investigates the short-term dynamics as well as the long-term relationship between natural gas consumption and economic growth in Nigeria,... 相似文献
426.
The influence of the polymers' properties on the solid-phase extraction recovery was studied. Different porous copolymers were used: di(methacryloyloxymethyl)naphtalene-divinylbenzene with ester functional groups (DMN-DVB), 4,4'-bis(maleimido)diphenylmethane-divinylbenzene with imide functional groups (BM-DVB), p,p'-dihydroxydiphenylmethane diglycidyl methacrylic ester-divinylbenzene (MEMDE-DVB) and p,p'-dihydroxydiphenylpropane diglycidyl methacrylic ester-divinylbenzene (MEDDE-DVB) with ester end hydroxyl functional groups. The extraction properties of new synthesized polymeric sorbents were compared with these of two commercial polymeric sorbents: styrene-divinylbenzene (SDB-1) and styrene-divinylbenzene with modified surface (StrataX). These sorbents were used in the SPE of phenol and hydroquinone from water samples. 相似文献
427.
Nalli S Horn OJ Grochowalski AR Cooper DG Nicell JA 《Environmental pollution (Barking, Essex : 1987)》2006,140(1):181-185
2-Ethylhexanol has been identified as a volatile organic compound (VOC) that contributes to the deterioration of indoor air quality. Plasticizers are common components of dust and building materials and are shown to be degraded by a variety of bacteria and fungi to produce 2-ethylhexanol and other metabolites. Of these, the 2-ethylhexanol has significant volatility and was observed in appreciable quantities. The degree to which 2-ethylhexanol is observed as a VOC in air samples would be limited by the fact that many of the microorganisms that are capable of producing this compound are also able to oxidize it to 2-ethylhexanoic acid, which is much less volatile. It is argued that an abiotic degradation mechanism of plasticizers that results in the generation of 2-ethylhexanol is unlikely and, if this did occur, other metabolites should have been observed. Thus, the microbial degradation of plasticizers is the most likely source of 2-ethylhexanol in indoor air. 相似文献
428.
基于室内超宽带信道测量研究建立了基于簇的时延抽头模型以及与距离和载频有关的新颖的路径损耗模型,建立了路径损耗同时与距离和频率的依赖关系.同时,研究发现视距和非视距接收信号幅度分别满足莱斯和瑞利分布.该模型对超宽带无线系统仿真和设计有重要的指导意义. 相似文献
429.
Holly S. Bradley Sean Tomlinson Michael D. Craig Adam T. Cross Philip W. Bateman 《Conservation biology》2022,36(1):e13667
Mitigation translocation is a subgroup of conservation translocation, categorized by a crisis-responsive time frame and the immediate goal of relocating individuals threatened with death. However, the relative successes of conservation translocations with longer time frames and broader metapopulation- and ecosystem-level considerations have been used to justify the continued implementation of mitigation translocations without adequate post hoc monitoring to confirm their effectiveness as a conservation tool. Mitigation translocations now outnumber other conservation translocations, and understanding the effectiveness of mitigation translocations is critical given limited global conservation funding especially if the mitigation translocations undermine biodiversity conservation by failing to save individuals. We assessed the effectiveness of mitigation translocations by conducting a quantitative review of the global literature. A total of 59 mitigation translocations were reviewed for their adherence to the adaptive scientific approach expected of other conservation translocations and for the testing of management options to continue improving techniques for the future. We found that mitigation translocations have not achieved their potential as an effective applied science. Most translocations focused predominantly on population establishment- and persistence-level questions, as is often seen in translocations more broadly, and less on metapopulation and ecosystem outcomes. Questions regarding the long-term impacts to the recipient ecosystem (12% of articles) and the carrying capacity of translocation sites (24% of articles) were addressed least often, despite these factors being more likely to influence ultimate success. Less than half (47%) of studies included comparison of different management techniques to facilitate practitioners selecting the most effective management actions for the future. To align mitigation translocations with the relative success of other conservation translocations, it is critical that future mitigation translocations conform to an established experimental approach to improve their effectiveness. Effective mitigation translocations will require significantly greater investment of time, expertise, and resources in the future. 相似文献
430.
Rehman Abdul Russell Elena Saleem Faisal Mahmood Khalid Abbas Aumber Eze Valentine C. Harvey Adam 《Journal of Polymers and the Environment》2022,30(10):4452-4462
Journal of Polymers and the Environment - Bio-based non-isocyanate poly(hydroxyurethanes) (NIPUs) have recently gained significant interest due to increasing awareness of the health and... 相似文献