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91.
M. Teresa S. D. Vasconcelos J. L. Lpez-Ruiz A. Garcia M. Fernanda C. Leal Adriano Fachini 《Aquacultural Engineering》2004,31(3-4):205-219
The yield of cultures of Emiliania huxleyi, a coccolithophore marine micro-alga species, in natural seawater and in seawater previously exposed to elutriates of ZEBEN-06 and ZESTEC-56, two zeolitic-nature products (ZNPs) (supernatant of 2.0 g l−1 of ZNP in natural seawater, stirred for 30 min) was evaluated. Total concentrations of dissolved trace metals and organic ligands (and respective conditional stability constants) in the initial media and at 7th day cultures were determined, by anodic and cathodic striping voltammetry. The changes introduced by the ZNPs in the media significantly enhanced E. huxleyi growth yield, the effect being more extent in the ZESTEC-56 elutriate. It was observed that both the ZNPs enriched the seawater with trace and not toxic quantities of Mn. In addiction, ZEBEN-06 removed small fractions of Cu and Zn from the media. The ZEBEN-06 elutriate stimulated the cell exudation but that of ZESTEC-56 inhibited exudation. Algae were also incubated in a culture medium with 0.05 g l−1 ZESTEC-56 in situ, and the growth yield was similar to that of the control culture. ZEBEN-06 was not studied in situ because it was hard to distinguish its particles from the cells, during cells counting. The ZESTEC-56 in situ enriched the medium in Mn, Cu, Pb and Cd, but impoverished it in Zn. The cell exudation was about four times higher in the presence of the ZNP in situ. Liberation/adsorption of micro-nutrients at the surface of the zeolites seems to be the cause of the observed changes in the biological response of the algae. The yield of the algal growth has economic relevance in aquaculture. On the other hand, ZNP are cheap, only small amounts (few mg l−1) are required and the addition of some nicro-nutrients may be omitted. Therefore, the inclusion of zeolites in algal cultures in aquaculture may be economically advantageous. However, it is recommendable an previous investigation, in order to select the zeolitic characteristics and concentration that will maximise the algal yield in each particular case (alga nature and seawater trace metal contents). 相似文献
92.
Virgínia H. Pohl Adriano B. Carregaro Carlize Lopes Martielo I. Gehrcke Daniel C.M. Muller Clarissa D. Garlet 《Canadian journal of veterinary research》2012,76(3):215-220
The aim of this study was to determine the viability and cardiorespiratory effects of the association of epidural alpha-2 adrenergic agonists and lidocaine for ovariohysterectomy (OH) in bitches. Forty-two bitches were spayed under epidural anesthesia with 2.5 mg/kg body weight (BW) of 1% lidocaine with adrenaline (CON) or in association with 0.25 mg/kg BW of xylazine (XYL), 10 μg/kg BW of romifidine (ROM), 30 μg/kg BW of detomidine (DET), 2 μg/kg BW of dexmedetomidine (DEX), or 5 μg/kg BW of clonidine (CLO). Heart rate (HR), respiratory rate (fR) and arterial pressures were monitored immediately before and every 10 min after the epidural procedure. Blood gas and pH analysis were done before, and at 30 and 60 min after the epidural procedure. Animals were submitted to isoflurane anesthesia if they presented a slightest sign of discomfort during the procedure. Time of sensory epidural block and postoperative analgesia were evaluated. All animals in CON and DEX, 5 animals in ROM and CLO, 4 animals in XYL, and 3 in DET required supplementary isoflurane. All groups, except CLO, showed a decrease in HR. There was an increase in arterial pressures in all groups. Postoperative analgesia lasted the longest in XYL. None of the protocols were totally efficient to perform the complete procedure of OH; however, xylazine provided longer postoperative analgesia than the others. 相似文献
93.
RR Hilário FH Rodrigues AG Chiarello I Mourthé 《Folia primatologica; international journal of primatology》2012,83(1):47-55
Line transect distance sampling (LTDS) can be applied to either trails or roads. However, it is likely that sampling along roads might result in biased density estimates. In this paper, we compared the results obtained with LTDS applied on trails and roads for two primate species (Callithrix penicillata and Callicebus nigrifrons) to clarify whether roads are appropriate transects to estimate densities. We performed standard LTDS surveys in two nature reserves in south-eastern Brazil. Effective strip width and population density were different between trails and roads for C. penicillata, but not for C. nigrifrons. The results suggest that roads are not appropriate for use as transects in primate surveys, at least for some species. Further work is required to fully understand this issue, but in the meantime we recommend that researchers avoid using roads as transects or treat roads and trails as covariates when sampling on roads is unavoidable. 相似文献
94.
Francesco Bisi Roberta Chirichella Francesco Chianucci Jost Von Hardenberg Andrea Cutini Adriano Martinoli Marco Apollonio 《Annals of Forest Science》2018,75(2):46
Key message
Climate factors affect seed biomass production which in turn influences autumn wild boar spatial behaviour. Adaptive management strategies require an understanding of both masting and its influence on the behaviour of pulsed resource consumers like wild boar.Context
Pulsed resources ecosystem could be strongly affected by climate. Disantangling the role of climate on mast seeding allow to understand a seed consumer spatial behaviour to design proper wildlife and forest management strategies.Aims
We investigated the relationship between mast seeding and climatic variables and we evaluated the influence of mast seeding on wild boar home range dynamics.Methods
We analysed mast seeding as seed biomass production of three broadleaf tree species (Fagus sylvatica L., Quercus cerris L., Castanea sativa Mill.) in the northern Apennines. Next, we explored which climatic variables affected tree masting patterns and finally we tested the effect of both climate and seed biomass production on wild boar home range size.Results
Seed biomass production is partially regulated by climate; high precipitation in spring of the current year positively affects seed biomass production while summer precipitation of previous year has an opposite effect. Wild boar home range size is negatively correlated to seed biomass production, and the climate only partially contributes to determine wild boar spatial behaviour.Conclusion
Climate factors influence mast seeding, and the negative correlation between wild boar home range and mast seeding should be taken into account for designing integrated, proactive hunting management.95.
Myxobolus porofilus sp. n. is described infecting the visceral cavity of Prochilodus lineatus (Valenciennes, 1836) cultivated in S?o Paulo State, Brazil. The plasmodial form of the parasite is 3-5 mm in length and appeared compressed between the wall of the visceral cavity and the pyloric caecum, reposing on this organ. The spores are small (length 5.7 +/- 0.3 microm, width 4.8 +/- 0.2 microm; mean +/- SD) and round to elliptical in frontal view. The valve surfaces are smooth and have sutural folds. The polar capsules are ovoid, small (length 1.6 +/- 0.1 microm, width 1.1 +/- 0.1 microm) and equal in size. The polar filaments have three turns aligned perpendicularly to the longitudinal axis of the capsule. A conspicuous polar filament pore is arranged at the anterior end of the spore. The only reaction observed upon histological analysis was the presence of a capsule of connective tissue surrounding the plasmodia. This is the first report of a myxosporean parasite in the Prochilodontidae. 相似文献
96.
97.
dos Santos Luana Mendes Ferraz Gabriel Araújo e Silva Barbosa Brenon Diennevan de Souza Diotto Adriano Valentim Maciel Diogo Tubertini Xavier Letícia Aparecida Gonçalves 《Precision Agriculture》2020,21(6):1227-1241
Precision Agriculture - The advance of digital agriculture combined with computational tools and Unmanned Aerial Vehicles (UAVs) has enabled the collection of data for reliably extracting... 相似文献
98.
Adriano D. C. Weber J. Bolan N. S. Paramasivam S. Koo Bon-Jun Sajwan K. S. 《Water, air, and soil pollution》2002,139(1-4):365-385
A field study (1993–1996) assessed the effects of applying unusually high rates of coal fly ash as a soil additive forthe turf culture of centipedegrass (Eremochloa ophiroides).In addition, the quality of the soil and the underlying groundwater was evaluated. A Latin Square plot design was employed to include 0 (control, no ash applied), 280, 560, and 1120 Mg ha-1 (mega gram ha-1, i.e., tonne ha-1)application rates of unweathered precipitator fly ash. The onceapplied fly ash was rototilled and allowed to weather for 8 months before seeding. Ash application significantly increasedthe concentrations in plant tissue of B, Mo, As, Be, Se, and Bawhile also significantly reducing the concentrations of Mg, Mn,and Zn. The other elements measured (i.e., N, K, Ca, Cu, Fe, Ag,Cd, Cr, Hg, Ni, Pb, Sb, Tl, Na, and Al) were not affected. Of these elements Mg, Cu, and Mo concentrations in plant tissue increased with time while B and Se decreased temporally. The diminution of B and Na appears to be related to the leaching ofsoluble salts from ash-treated soils. Of all the elements measured, only Mn produced significant correlation (p = 0.0001) between the tissue and soil extractable concentrations. Ash treatment elevated the soil pH to as high as 6.45 with theenhanced effect occurring primarily in the 0–15 cm depth. Soilsalinity increased with the application rate with the largestincreases occurring in the initial year of application. However,by the second year, most of the soluble salts had already leachedfrom the treatment zone into deeper depths, and by the fourthyear, these salts had completely disappeared from the profile.The chemical composition of the underlying groundwater was notadversely impacted by the ash application. Plant tissue and groundwater data however, indicate that much higher rates of fly ash can be used on this type of land use where the plant species is tolerant of soil salinity and does not appear tobioaccumulate potentially toxic trace elements. 相似文献
99.
Carregaro AB Neto FJ Beier SL Luna SP 《American journal of veterinary research》2006,67(10):1675-1680
OBJECTIVE: To investigate the effects of buprenorphine on cardiopulmonary variables and on abdominal auscultation scores in horses. ANIMALS: 6 healthy adult horses. PROCEDURES: Horses were restrained in stocks and allocated to 2 treatments in a randomized crossover design, with 1-week intervals between each treatment. Saline (0.9% NaCl) solution was administered IV as a control, whereas buprenorphine (10 mug/kg, IV) was administered to the experimental group. Cardiopulmonary data were collected for 120 minutes after buprenorphine or saline solution administration. Abdominal auscultation scores were monitored for 2 and 12 hours after drug administration in the control and experimental groups, respectively. RESULTS: Following control treatment, horses remained calm while restrained in the stocks and no significant changes in cardiopulmonary variables were observed throughout the study. Buprenorphine administration caused excitatory phenomena (restlessness and head shaking). Heart rate, cardiac index, and arterial blood pressure were significantly increased after buprenorphine administration until the end of the observational period (120 minutes). Minimal changes were found in arterial blood gas tensions. Abdominal auscultation scores decreased significantly from baseline for 4 hours after buprenorphine administration. CONCLUSIONS AND CLINICAL RELEVANCE: Buprenorphine induced excitement and hemodynamic stimulation with minimal changes in arterial blood gas tensions. These effects may impact the clinical use of buprenorphine in horses. Further studies are indicated to investigate the effects of buprenorphine on gastrointestinal motility and fecal output. 相似文献
100.
Rubini AS Dos Santos Paduan K Perez RR Ribolla PE O'Dwyer LH 《Veterinary parasitology》2006,137(1-2):168-171
Feline Hepatozoon species from Brazil was molecular identified and characterized for the first time in S?o Paulo state, Brazil. Partial sequences of the 18S rRNA gene from the Hepatozoon from three naturally infected cats were analyzed. Sequences revealed that feline Hepatozoon was closely related to the canine Hepatozoon canis from Brazil. 相似文献