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The yellow-legged clearwing (YLC) Synanthedon vespiformis (Lepidoptera: Sesiidae) occurs in the Mediterranean and central Europe. It is polyphagous, boring into the woody parts of broadleaf species including forest trees as well as various Rosaceae species. S. vespiformis has been reported as an economically important pest causing severe injury to stone fruit plantations. Many attractants for sesiid species were discovered by random field screening using 2,13- and 3,13-octadecadienyl alcohols, acetates and aldehydes, including one for S. vespiformis; and about 20 sex pheromones of sesiids have been identified so far. In the present study we identified the natural composition of the sex pheromone of YLC laboratory reared females as a blend of E3,Z13- and Z3,Z13-octadecadienyl acetates, at a ratio of 4:1. We developed an efficient lure for monitoring the pest. Pheromone funnel traps with rubber septa, impregnated with 1 mg pheromone blend, efficiently captured males for 10 weeks. Suspension of Shin-Etsu? ropes containing a 2:1 blend of E3,Z13-18:Ac and Z3,Z13-18:Ac at 13.74 mg/ha/h, resulted in shutdown of trap catches in the treated plots and closely situated neighboring plots indicating that mating disruption is feasible.  相似文献   
2.
Roe AM  Meyer CB  Nibbelink NP  Ben-David M 《Ecology》2010,91(11):3177-3188
We explored the interacting effects of marine-derived nutrient fertilization and physical disturbance introduced by coastal river otters (Lontra canadensis) on the production and nutrient status of pristine shrub and tree communities in Prince William Sound, Alaska, USA. We compared production of trees and shrubs between latrines and non-latrines, while accounting for otter site selection, by sampling areas on and off sites. Nitrogen stable isotope analysis (delta15N) indicated that dominant tree and shrub species assimilated the marine-derived N excreted by otters. In association with this uptake, tree production increased, but shrub density and nonwoody aboveground shrub production decreased. The reduced shrub production was caused by destruction of ramets, especially blueberry (Vaccinium spp.), through physical disturbance by river otters. False azalea (Menziesia ferruginea) ramets were less sensitive to otter disturbance. Although surviving individual blueberry ramets showed a tendency for increased production per plant, false azalea allocated excess N to storage in leaves rather than growth. We found that plant responses to animal activity vary among species and levels of biological organization (leaf, plant, ecosystem). Such differences should be accounted for when assessing the influence of river otters on the carbon budget of Alaskan coastal forests at the landscape scale.  相似文献   
3.
Few empirical works have examined the process through which CEO dispositions relate to organizational outcomes. In this study we examined the relationships between CEO values and organizational culture, and between organizational culture and firm performance. Data were collected from different sources (26 CEOs, 71 Senior Vice Presidents and 185 other organizational members), and include organizational financial performance data collected at two points in time. In support of our hypotheses, CEO self‐directive values were associated with innovation‐oriented cultures, security values were associated with bureaucratic cultures and benevolence values were related to supportive cultures. In turn, cultural dimensions showed differential associations with subsequent company sales growth, an index of organizational efficiency and assessments of employee satisfaction. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
4.
ABSTRACT: The economic feasibility of a large scale dual purpose (desalting water and power production) facility were evaluated. Although a site in the Tularosa basin of southern New Mexico was chosen as a case study for this analysis, it is believed that the approach and consequential results would be applicable to alternative sites in the Southwest. The basic project evaluated included: a) a ground water well field; b) a dual purpose, nuclear, desalination plant; c) a mineral recovery plant; and d) a reservoir for recreation and irrigation storage. Principle project outputs included electrical power, minerals, recreation, and water for either irrigated agricultural production or export to an adjoining river basin. Two alternative project designs were developed for detailed analysis. The first alternative encompassed all major project components. The results, in discounted net values used to assess the feasibility of the project, were essentially negative; that is, values were less than zero for full scale development. The net benefits ranged from $-986.57 million at a 5 percent discount rate, to $-1,137.528 million at a discount rate of 10 percent. In the second alternative, exportation of the desalted water from the Tularosa basin to two adjacent rivers was analyzed with somewhat better net benefits, ranging from $-382,527 million to $-478,612 million at the 5 and 10 percent discount rates.  相似文献   
5.
This article reports on the content and process used to evaluate environmental impacts caused by the development of 50 new settlements in the central Galilee region in northern Israel between 1978 and 1988. Some 60 different environmental and developmental factors and their interrelationships were identified. Selected physical changes that were defined as impacts were later evaluated. The evaluation method was based on intensive use of interviews with resource scientists and decision makers as experts. The data from interviews were used as the basis for factors identification, impact screening, and their rating. Experts used three types of criteria in the latter process: intensity of impact, the potential for its mitigation and compatibility with existing natural resource conservation, and environmental quality protection policy. Researchers concluded that reliance on experts with broad local experience eliminated the need for a more structured and detailed assessment method. The case study shows that experts provided creditable and reliable findings. They substituted the need for long periods of observation and largescale and costly data gathering, analysis, and evaluation.  相似文献   
6.
Crait JR  Ben-David M 《Ecology》2007,88(4):1040-1052
Animals that deposit aquatically derived nutrients on terrestrial landscapes link food webs and affect a variety of in situ processes. This phenomenon, however, is poorly documented in freshwater habitats, especially where species introductions have drastically changed an ecosystem's trophic structure. In this study, we used stable isotopes to document water-to-land nutrient transport by river otters (Lontra canadensis) around Yellowstone Lake, an ecosystem recently altered by nonnative species invasions. We then investigated the effects of otter fertilization on plant growth and prevalence at latrine (scent-marking) sites and evaluated how the recent changes to the lake's food web could influence these plant responses. Values of delta15N were higher on latrines compared to non-latrine sites in five of seven sample plant taxa. Additionally, latrine grasses had higher percentage N than those from non-latrines. Foliar delta15N positively related to fecal deposition rate for some plants, indicating that increased otter scent-marking led to a rise in these N values. Logistic regression models indicated that otters selected for well-shaded latrines with access to foraging. Atypical latrines, misclassified as non-latrines by the regression models, had values of delta15N similar to correctly classified latrines, suggesting that site effects alone cannot explain elevated N values at otter latrine sites. No difference in plant diversity or percent cover of N-fixing taxa occurred between latrine and nonlatrine sites, though specific genera did differ between site types. Measurements of shoot lengths indicated increased growth of some latrine currants (Ribes sp.). In Yellowstone Lake, a twofold reduction in otter numbers could result in an even greater decline in nutrient deposition at latrines, as otters may become less social in a system with decreased prey availability. Our results highlight the role of animals in linking aquatic and terrestrial habitats in inland freshwater systems and suggest that ongoing changes in the trophic structure of Yellowstone Lake could have unexpected ramifications well beyond the lake itself.  相似文献   
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8.
Prior to a relocation of a governmental organization in Israel, 155 workers responded to a questionnaire tapping three criteria: the intention to relocate, positive feelings, and stress reactions. The questionnaire also addressed potential correlates: biographical data, family-related variables, perceived attitudes of co-workers, job satisfaction and centrality, and anticipations regarding work and nonwork aspects. The intention to relocate was associated mainly with the perceived attitude of the spouse and the children. Stress experienced was most strongly related to the future job prospects, and the positive emotions were mostly correlated with the perceived favourability of the anticipated changes. The family-related variables were found to be significantly correlated with all the criteria. These results suggest that organization should direct efforts on spouse and children in order to influence employees' decisions and feelings regarding relocation. This and other implications are discussed.  相似文献   
9.
Fetoscopy and fetal blood sampling were performed in an attempt at prenatal monitoring of a pregnancy at risk for infantile hereditary agranulocytosis (Kostmann's disease). In smears of fetal blood three segmented neutrophils were found out of 200 nucleated cells (1 2/ per cent). Their presence, although in a lower percentage than in six age-matched controls, was considered to indicate that the fetus was not affected. The newborn infant has developed normally and at the age of four months has a normal number of segmented neutrophils in his peripheral blood. Feasibility of prenatal diagnosis of infantile hereditary agranulocytosis is discussed.  相似文献   
10.
ABSTRACT

Terpene-based cleaners are being widely used in industrial cleaning formulations because of their ability to replace suspected ozone-depleting chemicals such as 1,1,1-trichloroethane and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). Substitution of chlorinated solvents with ter-pene-based cleaners, however, is expected to result in increased discharges to wastewater from industrial operations. A pilot-scale study was conducted at the U.S. Environmental Protection Agency's (EPA) Test & Evaluation Facility in Cincinnati, OH, to quantify the fate of specific terpene compounds in the activated sludge wastewater treatment process. Biodegradation rates of terpenes were estimated from the difference between the influent terpene mass flow rates and the amounts volatilized to air, partitioned to waste sludge, and passed through the treatment process unchanged. Any chemical transformation of the terpene compounds studied was attributed to biodegradation.

Analytical methods were developed to determine ter-pene concentrations in aqueous and gaseous media. The fate of two common terpene compounds (d-limonene and terpinolene) were evaluated in three identical pilot-scale systems: (1) a system with a high target spike range (2–10 mg/L), (2) a system with a low target spike range (0.5–2 mg/L), and (3) a control system (no spike).

The study showed that the primary removal mechanism for the terpene compounds in the activated sludge process is biodegradation. Typically, greater than 90% of the mass of terpenes entering the aeration basin of the activated sludge process biodegrades to other compounds; volatilization from the reaction basin accounts for less than 10%, while loss to waste activated sludge and the secondary clarifier effluent accounts for less than 1%.  相似文献   
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