1,500 research outputs found
Statistical Analysis of Tropospheric Ozone Concentration
This paper analyzes ozone monitoring data obtained from 50 European stations operated by the Co-operative Programme for Monitoring and Evaluation of the Long Range Transmission of Air Pollutants in Europe (EMEP) and two stations maintained by the Austrian Environmental Agency. Data used in the analyses covered the summer period of the year 1990.
The analysis explores first time series of ozone concentration and establishes simple statistical parameters such as maximum, average, daily variation and exceedance indices. It is shown that different indices rank high at different locations in Europe, stressing the importance of well-based information when establishing relationships to environmental impacts. Different characteristic exposure patterns are identified for Northern Europe, Central Europe and the UK.
The analysis shows that at some stations also night time ozone concentration has a remarkable effect on cumulated excess ozone. Thus, caution should be exerted when excluding the nighttime values until more detailed data on the biological effects of nighttime high concentrations are obtained
The ecomics of ecosystems and biodiversity: scoping the scale
The G8 decided in March 2007 to initiate a “Review on the economics of biodiversity loss”, in the so called Potsdam Initiative: 'In a global study we will initiate the process of analysing the global economic benefit of biological diversity, the costs of the loss of biodiversity and the failure to take protective measures versus the costs of effective conservation. The study is being supported by the European Commission (together with the European Environmental Agency and in cooperation with the German Government. “The objective of the current study is to provide a coherent overview of existing scientific knowledge upon which to base the economics of the Review, and to propose a coherent global programme of scientific work, both for Phase 2 (consolidation) and to enable more robust future iterations of the Review beyond 2010.
Enzymes as Feed Additive to Aid in Responses Against Eimeria Species in Coccidia-Vaccinated Broilers Fed Corn-Soybean Meal Diets with Different Protein Levels
This research aimed to evaluate the effects of adding a combination of exogenous enzymes to starter diets varying in protein content and fed to broilers vaccinated at day of hatch with live oocysts and then challenged with mixed Eimeria spp. Five hundred four 1-d-old male Cobb-500 chickens were distributed in 72 cages. The design consisted of 12 treatments. Three anticoccidial control programs [ionophore (IO), coccidian vaccine (COV), and coccidia-vaccine + enzymes (COV + EC)] were evaluated under 3 CP levels (19, 21, and 23%), and 3 unmedicated-uninfected (UU) negative controls were included for each one of the protein levels. All chickens except those in unmedicated-uninfected negative controls were infected at 17 d of age with a mixed oral inoculum of Eimeria acervulina, Eimeria maxima, and Eimeria tenella. Live performance, lesion scores, oocyst counts, and samples for gut microflora profiles were evaluated 7 d postinfection. Ileal digestibility of amino acids (IDAA) was determined 8 d postinfection. Microbial communities (MC) were analyzed by G + C%, microbial numbers were counted by flow cytometry, and IgA concentrations were measured by ELISA. The lowest CP diets had poorer (P ≤ 0.001) BW gain and feed conversion ratio in the preinfection period. Coccidia-vaccinated broilers had lower performance than the ones fed ionophore diets during pre- and postchallenge periods. Intestinal lesion scores were affected (P ≤ 0.05) by anticoccidial control programs, but responses changed according to gut section. Feed additives or vaccination had no effect (P ≥ 0.05) on IDAA, and diets with 23% CP had the lowest (P ≤ 0.001) IDAA. Coccidial infection had no effect on MC numbers in the ileum but reduced MC numbers in ceca and suppressed ileal IgA production. The COV + EC treatment modulated MC during mixed coccidiosis infection but did not significantly improve chicken performance. Results indicated that feed enzymes may be used to modulate the gut microflora of cocci-vaccinated broiler chickens
The Effect of a Femoral Fracture Sustained before Skeletal Maturity on Bone Mineral Density: A Long-Term Follow-Up Study
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Valence electronic structure and photofragmentation of 1,1,1,2-tetrafluoroethane (CF3-CH2F)
The electronic structure and fragmentation of the hydrofluorocarbon compound 1,1,1,2-tetrafluoroethane (CF3-CH2F) were studied using spectroscopical methods and quantum chemical calculations. Valence photoelectron spectra and the ionic fragmentation products were recorded with synchrotron radiation in the vacuum ultraviolet (VUV) region. The geometric and electronic structures of the CF3-CH2F molecule were calculated using the complete active space perturbation theory of second order. The calculated vertical ionization energies were used to interpret the experimental photoelectron spectrum. VUV photodissociation of the sample molecule was studied with photoelectron-photoion coincidence spectroscopy. Coincident ion yields are shown for several cations as a function of electron binding energy. The experimental data are discussed in comparison with theory and previous work
Field ionization of high-Rydberg fragments produced after inner-shell photoexcitation and photoionization of the methane molecule
We have studied the production of neutral high-Rydberg (HR) fragments from the CH4 molecule at the C 1s -> 3p excitation and at the C 1s ionization threshold. Neutral fragments in HR states were ionized using a pulsed electric field and the resulting ions were mass-analyzed using an ion time-of-flight spectrometer. The atomic fragments C(HR) and H(HR) dominated the spectra, but molecular fragments CHx(HR), x = 1-3, and H-2(HR) were also observed. The production of HR fragments is attributed to dissociation of CH4+ and CH42+ ions in HR states. Just above the C 1s ionization threshold, such molecular ionic states are created when the C 1s photoelectron is recaptured after single or double Auger decay. Similar HR states may be reached directly following resonant Auger decay at the C 1s -> 3p resonance. The energies and geometries of the parent and fragment ions have been calculated in order to gain insight into relevant dissociation pathways. (C) 2015 AIP Publishing LLC
The Presence of Visual Neglect after Thrombolytic Treatment in Patients with Right Hemisphere Stroke
Visual neglect (VN) is a common consequence of right hemisphere (RH) stroke. The aims of this study were to explore the presence of VN after RH stroke in the patients with (T+) or without (T−) thrombolytic treatment, and to determine whether thrombolysis is a predictor of VN. The study group consisted of 77 RH infarct patients. VN was evaluated with six conventional subtests of the Behavioural Inattention Test (BIT). Stroke severity was assessed using the National Institute of Health Stroke Scale (NIHSS). In the neuropsychological examination, 22% of all RH stroke patients had VN. VN was present in 15% of the patients in the T+ group and in 28% of the patients in the T− group, but the difference was not statistically significant. Despite that, patients in the T− group had a higher risk of VN than patients in the T+ group. Our results suggest that thrombolysis independently predicted absence of VN
Estimation of genetic parameters for test-day milk production at different stages of lactation of Finnish Ayrshire heifers
Genetic parameters for test-day milk production at different stages of lactation of Finnish Ayrshire heifers were estimated with the REML method using the AI algorithm and animal model. The data consisted of 38 679 first lactation test-day milk yields of 4205 cows from 231 herds in three geographical regions (North Savo, Central Ostrobothnia and Lapland). To identify different test days, records were numbered according to the days in milk after calving, and were further categorized into three part-lactations according to the test-day classification. Expressions in the three part-lactations were considered as separate traits, and tests were treated as repeated observations within the trait. Heritability estimates for test-day milk yield varied between 0.11 and 0.17, being lowest at the beginning of lactation. Genetic correlations between test-day milk yields at different trimesters ranged from 0.64 to 0.91, being highest between consecutive trimesters. Standard errors of the estimates of genetic parameters varied between 0.02 and 0.08. Genetic interrelationships differed from 1.0, supporting the assumption that genetic variation exists in the shape of the lactation curve. The necessity of considering deviations from the general lactation curve in the test-day model, e.g. fitting random regression coefficients, is discussed
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