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571.
Claudia Borgioli Giovanni Maria Marchetti Felicitas Scapini 《Behavioral ecology and sociobiology》1999,45(2):79-85
Under stressful conditions (e.g. finding themselves on dry or moisture-saturated substrates) littoral talitrids (Crustacea,
Amphipoda) demonstrate zonal orientation, in which they must promptly reach the optimal zone of the beach, the wet fringe
near the shoreline. A relationship might therefore exist between the use of orientation and the frequency of such stressful
conditions in the natural environment. Moreover, the efficiency of orientation toward the sea could be related to the possibility
of using strategies other than zonal orientation in order to avoid stress. This study analysed the actual use and efficiency
of orientation under natural conditions of four Talitrus saltator (Montagu, 1808) populations from Mediterranean and northern European Atlantic coasts with different ecological features.
Orientation tests were carried out on the beach with all natural cues available. Then the same individuals underwent control
experiments to study their sun orientation far from the sea in an experimental arena. The following results emerge from the
comparison of the circular distributions: (1) marked differences among populations in the precision of zonal recovery under
natural conditions; (2) a common solar orientation capacity in the control tests far from the sea; (3) different orientation
choices of the same individuals according to the test conditions, natural or controlled. The habitat diversity of the four
populations (amount, distribution and kind of detritus and wrack on the beach, degree of coastal erosion, orientation of the
shoreline, human use of the beach) provides an ecological interpretation for the differences in orientation observed among
populations.
Received: 13 October 1997 / Accepted after revision: 26 April 1998 相似文献
572.
Helen Carnaghan Catherine P. James Paul B. Charlesworth Marco Ghionzoli Susana Pereira Mohamed Elkhouli David Baud Paolo De Coppi Greg Ryan Prakesh S. Shah Mark Davenport Anna L. David Agostino Pierro Simon Eaton Gastroschisis Study Group 《黑龙江环境通报》2020,40(8):991-997
Objective
In gastroschisis, there is evidence to suggest that gut dysfunction develops secondary to bowel inflammation; we aimed to evaluate the effect of maternal antenatal corticosteroids administered for obstetric reasons on time to full enteral feeds in a multicenter cohort study of gastroschisis infants.Methods
A three center, retrospective cohort study (1992-2013) with linked fetal/neonatal gastroschisis data was conducted. The primary outcome measure was time to full enteral feeds (a surrogate measure for bowel function) and secondary outcome measure was length of hospital stay. Analysis included Mann-Whitney and Cox regression.Results
Of 500 patients included in the study, 69 (GA at birth 34 [25-38] weeks) received antenatal corticosteroids and 431 (GA at birth 37 [31-41] weeks) did not. Antenatal corticosteroids had no effect on the rate of reaching full feeds (Hazard ratio HR 1.0 [95% CI: 0.8-1.4]). However, complex gastroschisis (HR 0.3 [95% CI: 0.2-0.4]) was associated with an increased time to reach full feeds and later GA at birth (HR 1.1 per week increase in GA [95% CI: 1.1-1.2]) was associated with a decreased time to reach full feeds.Conclusion
Maternal antenatal corticosteroids use, under current antenatal steroid protocols, in gastroschisis is not associated with an improvement in neonatal outcomes such as time to full enteral feeds or length of hospital stay. 相似文献573.
Silvia Becagli Emiliano Castellano Omar Cerri Mark Curran Massimo Frezzotti Federica Marino Andrea Morganti Marco Proposito Mirko Severi Rita Traversi Roberto Udisti 《Atmospheric environment (Oxford, England : 1994)》2009,43(5):1051-1058
Firn core methanesulphonic acid (MSA) stratigraphy from Talos Dome (East Antarctica) was compared with anomalies of the satellite-measured sea ice extent (1973–1995) in the Ross Sea and Wilkes Land oceanic sector. In spite of the sparseness of sea ice data, the MSA maxima fit with many positive sea ice anomalies in the Ross Sea. This evidence suggests that marine biogenic activity enhanced by large sea ice cover is an important, but not exclusive, factor in controlling MSA concentration in snow precipitation at Talos Dome. Other than source intensity, differences in regional atmospheric transport mechanisms affect the arrival of MSA-rich aerosol at Talos Dome. To clarify the role of transport processes in bringing biogenic aerosol to Talos Dome, a spectral analysis was applied to the MSA, SOI (South Oscillation Index), and SAM (Southern Annular Mode) record. Synchronicity or phase shift between the chemical signature and atmospheric circulation modes were tested. The variations in the MSA profile have a periodicity of 6.9, 4.9, 3.5, and 2.9 years. The 6.9 and 2.9 year periodicities show a strong positive correlation and are synchronous with corresponding SOI periodicity. This variability could be related to an increase in MSA source intensity (by dimethylsulphide from phytoplanktonic activity) linked to the sea ice extent in the Ross Sea area, but also to an increased strength in transport processes. Both of these factors are correlated with La Niña events (SOI positive values). Furthermore, SAM positive values are related to an increased sea ice extent in the Ross Sea sector and show two main periodicities 3.3 and 3.8 years. These periodicities determine the MSA variability at 3.5 years. However, the effect of intensification of the polar vortex and the consequent reduction in transport process intensity, which reduce the delivery of air masses enriched in MSA from oceanic areas to Talos Dome, make the effect of the SAM on the MSA concentration at Talos Dome less active than the SOI. In this way, snow deposition at the Talos Dome records larger MSA concentration by the combined effects of increased source emissions and more efficient transport processes. The MSA record from Talos Dome can therefore be considered a reliable proxy of sea ice extent when the effect of changes in transport processes in this region of Antarctica is considered. Over the previous 140 years, these conditions occur with a periodicity of 6.9 years. 相似文献
574.
Marco Ostoich Emilia Aimo Rita Frate Marina Vazzoler Silvia Stradella Paolo Osti 《Chemistry and Ecology》2007,23(1):43-62
Wastewaters are a source of pathogenic micro-organisms in the environment. The microbial load and residues found in the final effluents of wastewater-treatment plants (WWTPs) depend on the WWTPs' abatement capacity and the final disinfection treatment systems applied to wastewaters before discharge into water. A historical database with data on surface and marine-coastal water quality and on the characterization of WWTP effluents was made using data from 1997 to 2004 to assess the microbiologic impact along the coast of the Venice province (Italy, northern Adriatic sea). The monitoring of river and sea discharges along the coast is integrated with the application of the Synthetic Pluriennal Faecalization Index (ISPF). The experimental study was conducted in the period from November 2002 to April 2004 by the Veneto Regional Environmental Prevention and Protection Agency. The results of this investigation on faecal contamination together with previous data are presented with a preliminary performance characterization of the WWTPs' disinfection technologies (sodium hypochlorite, peracetic acid, UV rays, and ozone). 相似文献
575.
The EMAS Regulation (Reg 761/01 EC) is EU scheme implemented by the European Commission since 1993 and it is for the implementation of an Environmental Management System (EMS) by any organization. The EMS was originally proposed by the European Commission and by the ISO as the frontrunner of a series of policy tools that enable companies to simultaneously pursue environmental objectives and competitive targets in a synergetic way.Based on the unique dataset of the EVER project, this paper investigates whether or not an EMS implemented within the EMAS Regulation has any effect on firm performance both from an environmental and a competitive point of view. Our econometric analysis shows the positive impact of a well-designed environmental management system on environmental performance and, as a consequence, on technical and organizational innovations. Effects on other competitive variables such as market performance, resource productivity and intangible assets are not strongly supported. 相似文献
576.
We questioned the different interpretations of ecological sexual segregation from a novel perspective, i.e., by carrying out
diverse temporal and spatial scale analyses within a long-term study (1984–2003). Thus we combined spatial (small/large) and
temporal (small/large) scale analyses to identify the factors generating sexual segregation in fallow deer in San Rossore,
Italy. The study site was divided into an eastern sector characterized by human disturbance (DS) and a western undisturbed
sector (US). According to census data, human presence increased in DS from 1984, and while females gradually abandoned it,
males remained—thus supporting the predation risk hypothesis (large spatial and temporal scale)—and actually increased their
presence in DS, where they seemingly benefited from a lower female density. This supported the indirect competition hypothesis.
The analysis of data on a large temporal and small spatial scale confirmed that intersexual competition, in particular for
grass, was higher in a crowded pasture in US. Observations by means of radio-telemetry of 23 adult females and 25 adult males
(1997–2001, reduced temporal and large spatial scale) showed that large scale segregation was relevant during the day and
disappeared at night, when disturbance was absent and also the females reached DS. This also supported the predation risk
hypothesis. Moreover, sexes showed different habitat choices inside DS at night, thus supporting the forage selection hypothesis
(small spatial and temporal scale). In conclusion, failure to address the whole set of combinations of spatial and temporal
scale analyses would have led to monocausal explanations of ecological sexual segregation. 相似文献
577.
Patrizia Jereb Rita Cannas Porzia Maiorano Giambattista Bello Fulvio Garibaldi Marco Mereu Francesco G. Ancona Giovanni Ammendolia Pietro Battaglia Önder Duysak Hendrik Jan T. Hoving Eugenia Lefkaditou Marek R. Lipinski Riccardo Melis Panagiota N. Peristeraki Sergio Ragonese Teresa Romeo Alp Salman Begonia M. Santos Alberto Villari Danila Cuccu 《Marine Biology》2016,163(9):192
578.
579.
Francesco Paladini de Mendoza Simone Bonamano Giuseppe Stella Monica Giovacchini Dario Capizzi Fulvio Fraticelli Sergio Muratore Calogero Burgio Sergio Scanu Maximo A. Peviani Marco Marcelli 《Journal of Coastal Conservation》2016,20(1):13-29
The present work proposes a siting process for the detection of a suitable site for wave energy exploitation. The choice of a suitable site is based on the good agreement between energy availability, environmental sustainability, and equipped facilities to exploit wave energy. The case study in the northern Latium coast is explicative because in this area there are several activities that affect marine ecosystems, and the introduction of renewable energies promote the reduction of anthropic pressures. The nearshore wave power is studied through the numerical wave model (CMS-Wave), and available wave buoys along the coast were used to compare numerical results. In correspondence with Civitavecchia harbour, the largest nearshore wave energy was found; the large depth in front of the breakwater allows to conserve a great part of offshore wave power, with an average dissipation rate of 10 % less than offshore, with mean annual available wave energy of 25.4 MWh/m and seasonal fluctuation of 5.4 MWh/m. This area appears to be an optimal site for nearshore and shoreline wave energy device tests and installations, for energy availability (intermediate level respect Mediterreanean Sea), low potential environmental impact, easier accessibility, and policy oriented towards a larger sustainability of harbour activities. 相似文献
580.
Gaoxiang Ying John Sansalone Srikanth Pathapati Giuseppina Garofalo Marco Maglionico Andrea Bolognesi Alessandro Artina 《Frontiers of Environmental Science & Engineering》2012,6(5):638-648
Control of rainfall-runoff particulate matter (PM) and PM-bound chemical loads is challenging; in part due to the wide gradation of PM complex geometries of many unit operations and variable flow rates. Such challenges and the expense associated with resolving such challenges have led to the relatively common examination of a spectrum of unit operations and processes. This study applies the principles of computational fluid dynamics (CFD) to predict the particle and pollutant clarification behavior of these systems subject to dilute multiphase flows, typical of rainfall-runoff, within computationally reasonable limits, to a scientifically acceptable degree of accuracy. The Navier-Stokes (NS) system of nonlinear partial differential equations for multiphase hydrodynamics and separation of entrained particles are solved numerically over the unit operation control volume with the boundary and initial conditions defined and then solved numerically until the desired convergence criteria are met. Flow rates examined are scaled based on sizing of common unit operations such as hydrodynamic separators (HS), wet basins, or filters, and are examined from 1 to 100 percent of the system maximum hydraulic operating flow rate. A standard turbulence model is used to resolve flow, and a discrete phase model (DPM) is utilized to examine the particle clarification response. CFD results closely follow physical model results across the entire range of flow rates. Post-processing the CFD predictions provides an in-depth insight into the mechanistic behavior of unit operations by means of three dimensional (3-D) hydraulic profiles and particle trajectories. Results demonstrate the role of scour in the rapid degradation of unit operations that are not maintained. Comparisons are provided between measured and CFD modeled results and a mass balance error is identified. CFD is arguably the most powerful tool available for our profession since continuous simulation modeling. 相似文献