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31.
Schooling decisions in guppies (Poecilia reticulata) are based on familiarity rather than kin recognition by phenotype matching 总被引:4,自引:0,他引:4
Evidence from a number of freshwater species indicates that fish prefer to school with familiar individuals. Do they also choose to associate with kin? Our experiment tested this idea using the Trinidadian guppy, Poecilia reticulata, a species whose reproductive biology favours the association of kin groups. Juveniles reared together were able to recognise one another on the basis of either visual or chemical cues, but showed no preference for schooling with unfamiliar kin. We therefore conclude that any naturally occurring kin groups in this species will occur as a result of familiarity rather than as a consequence of kin recognition based on phenotype matching. 相似文献
32.
A sequential zero valent iron and aerobic biodegradation treatment system for nitrobenzene 总被引:27,自引:0,他引:27
The remediation of nitroaromatic contaminated groundwater is sometimes difficult because nitroaromatic compounds are resistant to biodegradation and, when they do transform, the degradation of the products may also be incomplete. A simple nitroaromatic compound, nitrobenzene, was chosen to assess the feasibility of an in situ multi-zone treatment system at the laboratory scale. The proposed treatment system consists of a zero valent granular iron zone to reduce nitrobenzene to aniline, followed by a passive oxygen release zone for the aerobic biodegradation of the aniline daughter product using pristine aquifer material from Canadian Forces Base (CFB) Borden, Ontario, as an initial microbial source. In laboratory batch experiments, nitrobenzene was found to reduce quickly in the presence of granular iron forming aniline, which was not further degraded but remained partially sorbed onto the granular iron surface. Aniline was found to be readily biodegraded with little metabolic lag under aerobic conditions using the pristine aquifer material. A sequential column experiment, containing a granular iron reducing zone and an aerobic biodegradation zone, successively degraded nitrobenzene and then aniline to below detection limits (0.5 microM) without any noticeable reduction in hydraulic conductivity from biofouling, or through the formation of precipitates. 相似文献
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Lukas Stark Michael Düring Stefan Schoenawa Jan Enno Maschke Cuong Manh Do 《Traffic injury prevention》2019,20(4):S126-S132
AbstractObjective: The Vision Zero initiative pursues the goal of eliminating all traffic fatalities and severe injuries. Today’s advanced driver assistance systems (ADAS) are an important part of the strategy toward Vision Zero. In Germany in 2018 more than 26,000 people were killed or severely injured by traffic accidents on motorways and rural roads due to road accidents. Focusing on collision avoidance, a simulative evaluation can be the key to estimating the performance of state-of-the-art ADAS and identifying resulting potentials for system improvements and future systems.This project deals with the effectiveness assessment of a combination of ADAS for longitudinal and lateral intervention based on German accident data. Considered systems are adaptive cruise control (ACC), autonomous emergency braking (AEB), and lane keeping support (LKS).Methods: As an approach for benefit estimation of ADAS, the method of prospective effectiveness assessment is applied. Using the software rateEFFECT, a closed-loop simulation is performed on accident scenario data from the German In-Depth Accident Study (GIDAS) precrash matrix (PCM). To enable projection of results, the simulative assessment is amended with detailed single case studies of all treated cases without PCM data.Results: Three categories among today’s accidents on German rural roads and motorways are reported in this study: Green, grey, and white spots.Green spots identify accidents that can be avoided by state-of-the-art ADAS ACC, AEB, and LKS. Grey spots contain scenarios that require minor system modifications, such as reducing the activation speed or increasing the steering torque. Scenarios in the white category cannot be addressed by state-of-the-art ADAS. Thus, which situations demand future systems are shown. The proportions of green, grey, and white spots are determined related to the considered data set and projected to the entire GIDAS.Conclusions: This article describes a systematic approach for assessing the effectiveness of ADAS using GIDAS PCM data to be able to project results to Germany. The closed-loop simulation run in rateEFFECT covers ACC, AEB, and LKS as well as relevant sensors for environment recognition and actuators for longitudinal and lateral vehicle control.Identification of green spots evaluates safety benefits of state-of-the-art level 0–2 functions as a baseline for further system improvements to address grey spots. Knowing which accidents could be avoided by standard ADAS helps focus the evolution of future driving functions on white spots and thus aim for Vision Zero. 相似文献
34.
Zerovalent iron encapsulated chitosan nanospheres - a novel adsorbent for the removal of total inorganic arsenic from aqueous systems 总被引:1,自引:0,他引:1
Evaluation of Chitosan zerovalent Iron Nanoparticle (CIN) towards arsenic removal is presented. Addition of chitosan enhances the stability of Fe(0) nano particle. Prepared adsorbent was characterized by FT-IR, SEM EDX, BET and XRD. It was found that, with an initial dose rate of 0.5 g L−1, concentrations of As (III) and As (V) were reduced from 2 mg L−1 to <5 μg L−1 in less than 180 min and the adsorbent was found to be applicable in wide range of pH. Langmuir monolayer adsorption capacity was found to be 94 ± 1.5 mg g−1 and 119 ± 2.6 mg g−1 at pH 7 for As (III) and As (V) respectively. Major anions including sulfate, phosphate and silicate did not cause significant interference in the adsorption behavior of both arsenite and arsenate. The adsorbent was successfully recycled five times and applied to the removal of total inorganic arsenic from real life groundwater samples. 相似文献
35.
Parameters that influence the zero valent iron mediated degradation of the pharmaceutical diazepam (DZP) were evaluated including the iron concentration and its pre-treatment, the effect of complexation with EDTA and oxic versus anoxic condition. It was observed that acid pre-treatment of iron particles is important for degradation efficiency and that H2SO4 is a better choice than HCl, resulting in higher degradation of DZP. Under oxic conditions, the degradation of DZP achieved 96% after 60 min using Fe0 (25 g L−1) pre-treated with H2SO4 in the presence of EDTA (119 mg L−1), while mineralization achieved around 60% after the same time. Under anoxic conditions, degradation occurred, however at lower extent, achieving 67% after 120 min. The addition of EDTA improved the treatment efficiency in 20% leading to 99% DZP degradation after 120 min. The first intermediates formed during DZP degradation were identified using LC/MS analysis and revealed the formation of mono- and di-hydroxylated products from DZP during Fe0/EDTA/O2 degradation, which evidences that OH was the main oxidizing species formed in this process. 相似文献
36.
Xavier Bonnet Don Bradshaw Richard Shine David Pearson 《Behavioral ecology and sociobiology》1999,46(4):267-272
Large (to >1 m), diurnally active tiger snakes (Notechis scutatus) are abundant on Carnac Island, near the coast of Western Australia. Our behavioural and mark-recapture studies provide the
first ecological data on this population, and reveal a surprising phenomenon. Many adult tiger snakes have had their eyes
destroyed, apparently during nest defence, by silver gulls (Larus novaehollandiae). This loss of vision did not reduce the snakes' body condition (mass relative to length), or their rates of growth or survival
(measured over a 12-month period). Blind male snakes trail-followed females, and mated successfully. Thus, destruction of
a major sensory modality had no detectable effect on these predators. This result is strongly counter-intuitive, but mirrors
an earlier report of congenital blindness (without ill-effects) in American viperid snakes. Similarities between the two systems
(island populations, highly venomous snakes, reliance on sessile prey) clarify the circumstances under which the loss of vision
does not reduce an organism's viability. These natural experiments support Gans' hypothesis of “momentarily excessive construction”
in that the snakes possess a complex organ system that they do not actually require for successful feeding, survival or reproduction.
Received: 30 November 1998 / Received in revised form: 24 April 1999 / Accepted: 9 May 1999 相似文献
37.
Stacy Langsdale Allyson Beall Elizabeth Bourget Erik Hagen Scott Kudlas Richard Palmer Diane Tate William Werick 《Journal of the American Water Resources Association》2013,49(3):629-638
Collaborative Modeling for Decision Support integrates collaborative modeling with participatory processes to inform natural resources decisions. Practitioners and advocates claim that the approach will lead to better water management, balancing interests more effectively and reducing the likelihood of costly legal delays. These claims are easy to make, but the benefits will only be realized if the process is conducted effectively. To provide guidance for how to conduct an effective collaborative modeling process, a task committee cosponsored by the Environmental Water Resources Institute (EWRI) of the American Society of Civil Engineers and by the U.S. Army Corps of Engineers' Institute for Water Resources developed a set of Principles and Best Practices for anyone who might convene or conduct collaborative modeling processes. The guidance is intended for both conflict resolution professionals and modelers, and our goal is to integrate these two fields in a way that will improve water resources planning and decision making. Here, the set of eight principles is presented along with a selection of associated best practices, illustrated by two different case examples. The complete document is available at: http://www.computeraideddisputeresolution.us/bestpractices/ . 相似文献
38.
PROBLEM: A prior study indicated that zero tolerance laws differ in their enforceability and likelihood of enforcement, with California's law being easier to enforce than New York's, and New Mexico's being the hardest of all. The question is, do these differences in enforcement affect teenagers' knowledge and perception of these laws? METHOD: A telephone survey was conducted to investigate awareness of the laws among 17-20 year olds in these three states and perceptions of enforcement. RESULTS: Estimated percentages of teenagers who knew of the laws were much higher in New York and California (71% and 65%, respectively) than in New Mexico (34%). Perceptions that police were enforcing the law, that licenses could be suspended, and that penalties were often applied were also lowest in New Mexico. IMPACT ON INDUSTRY: The potential of zero tolerance laws will not be realized without better awareness among young people. Full enforcement of the laws accompanied by publicity about the enforcement is recommended. Changes to the laws and their application may encourage enforcement efforts. 相似文献
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