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161.
Mariusz Ł. Mamiński Magdalena Król Armando G. McDonald David N. McIlroy Ishwar B. Niraula Joanna Czechowska Paweł Parzuchowski 《Wood Science and Technology》2013,47(5):1019-1031
A procedure for rapidly modifying beech wood using a thermally initiated solvent-free grafting system was examined. In the modification, butyl acrylate and butyl methacrylate were used as vinyl monomers. Free radicals were generated from 2,2′-azobis(2-methylpropionitrile) or benzoyl peroxide at 103 and 180 °C by contact heating of the modified material. Chemical changes in the material were investigated by FTIR and X-ray photoelectron spectroscopies. The modification resulted in decreased surface wetting of the material manifested by increased water contact angles. The hardness of the resultant material decreased, while its color changed by the effect of temperature. It was shown that the approach allowed for efficient thermal-initiated modification of wood with rapid contact heating. 相似文献
162.
Anna Dupleix Domingos De Sousa Meneses Mark Hughes Rémy Marchal 《Wood Science and Technology》2013,47(6):1231-1241
There is a lack of quantitative data on the penetration depth and the amount of energy absorbed by green wood under infrared (IR) radiation. This lack of knowledge is a potential barrier to the development of IR heating as an alternative to soaking as a means of warming logs prior to peeling in the manufacture of plywood. Experimental measurements of normal hemispherical spectral reflectance and transmittance over the range 550–5,500 cm?1 wavenumbers on four wood species, beech, birch, Douglas-fir and spruce have brought new knowledge on mid-infrared absorption properties of green wood and removed some uncertainties. For instance, it is not possible to deliver energy deeper than up to 0.3 mm below the wood surface because 70–90 % of all incident IR radiation on the wood surface is absorbed in this layer. Some wood features, such as surface quality, the presence of knots and of free water in wood (the latter two having a more significant effect) influence the amount of energy absorbed. These results illustrate that IR radiation can heat the surface layers, but then heat penetrates deeper into the inside layers of wood by conduction. 相似文献
163.
Paola De Benedictis Cristian De Battisti Sabrina Marciano Franco Mutinelli Ilaria Capua Giovanni Cattoli 《Veterinary journal (London, England : 1997)》2013,195(3):388-390
Replication competent vaccines have been used successfully for the control of terrestrial rabies, mainly in wildlife; however, these vaccine strains occasionally may induce rabies. In this study, a pyrosequencing protocol for the rapid identification of vaccine-associated rabies viruses was applied to the 2008–2011 Italian epidemic. There was no evidence of vaccine-associated rabies cases following oral vaccination of foxes with the SAG2 and SADB19 vaccine strains. 相似文献
164.
165.
Joanna Hedley Livia Benato Gemma Fraga Christopher Palgrave Kevin Eatwell 《Journal of Exotic Pet Medicine》2013,22(2):212-217
A 2.5-year-old male African pygmy hedgehog (Atelerix albiventris) was presented with a 2-week history of lethargy, reduced appetite, and general weakness. Based on the clinical signs and heart valve abnormalities observed during an echocardiography examination, a provisional diagnosis of endocardiosis or endocarditis was made. Immediate therapeutic intervention consisted of furosemide, pimobendan, and amoxicillin/clavulanate. Despite medical treatment, 2 weeks following presentation, the hedgehog’s physical condition deteriorated to the point that euthanasia was recommended for the patient and agreed to by its owner. A postmortem examination was performed and tissue samples submitted for histopathology revealed a final diagnosis of valvular endocardiosis and wobbly hedgehog syndrome. 相似文献
166.
Simone M. Cacciò Anna Rosa Sannella Valeria Mariano Silvia Valentini Franco Berti Fabio Tosini Edoardo Pozio 《Veterinary parasitology》2013,191(1-2):128-131
An outbreak of cryptosporidiosis occurred in a mixed sheep/cattle farm of Central Italy in October 2011. A total of 450 ovines (250 sheep and 200 lambs) and 140 bovines (130 cows and 10 calves) were housed in two separated units, at the time of the outbreak. About half of the lambs had diarrhea due to Cryptosporidium sp. with a mortality rate of 80%; calves were not infected. Genomic DNA was extracted from an archived slide and from fecal specimens, and the parasite was identified as Cryptosporidium parvum by PCR and sequence analysis at the CpA135 gene. Genotyping at the GP60 gene showed the presence of a very rare genotype, IIaA20G2R1. Shortly after the outbreak was identified, the son of the farm's owner, aged 18 months, experienced an acute gastroenteritis and was hospitalized due to recurrent episodes of diarrhea, fever, vomiting and lack of appetite. The feces tested negative for bacteria and viruses, whereas cryptosporidiosis was diagnosed by microscopy and an immunochromatographic test. Molecular typing identified the C. parvum genotype IIaA20G2R1 in the feces of the child. This is the first case of transmission of cryptosporidiosis in Italy involving lambs as source of oocysts infectious to humans. 相似文献
167.
Joanna Sousa Vasconcelos Franco António ChaveiroAna Góis BSc Fernando Moreira da Silva PhD 《Journal of Equine Veterinary Science》2013
This study investigated the effects of ascorbic acid and α-tocopherol supplementation on semen quality parameters of equine thawed-frozen semen. Semen was divided in seven different treatments in a final concentration of 100 × 106 sperm/mL by using Gent extender containing no supplements (control) and the following supplements with three different concentrations: α-tocopherol (0.5, 1, and 2 mM) and ascorbic acid (0.45, 0.9, and 1.8 g/L). After thawing, all samples were maintained at 37°C, while analyses were performed at 0, 60, and 120 minutes. Evaluation of viability and acrosome status (using Pisum sativum agglutinin conjugated to fluorescein isothiocyanate and propidium iodide), mitochondrial membrane potential (5,5′,6,6′-tetrachloro-1,1′,3,3′tetraethylbenzimidazolyl carbocyanine iodine [JC-1]), membrane lipid peroxidation (LPO; C11-BODIPY581/591), and stability of the plasmatic membrane (merocyanine 540 and Yo-Pro-1) of each sample was determined by flow cytometry. Relative to the control group, supplementation with α-tocopherol improved (P ≤ .05) postthaw membrane LPO, yet the higher concentrations of ascorbic acid (0.9 and 1.8 g/L, respectively) showed a negative effect on membrane LPO. Neither antioxidant significantly increased (P > .05) the acrosome integrity and mitochondrial membrane potential of frozen-thawed spermatozoa, although supplementation with α-tocopherol and ascorbic acid (0.9 and 1.8 g/L, respectively) had a positive effect on membrane integrity and stability (P ≤ .05). For all semen parameters, the lower concentration of ascorbic acid (0.45 g/L) did not show significant differences (P > .05) compared with the control. In conclusion, α-tocopherol seems to be an efficient antioxidant for reducing the oxidative stress provoked by cryopreservation, decreasing lipid peroxidation on equine spermatozoa. 相似文献
168.
169.
Zs. Bohák F. Szabó J.-F. Beckers N. Melo de Sousa O. Kutasi K. Nagy O. Szenci 《Domestic animal endocrinology》2013
Daily fluctuations of cortisol concentration in the blood or saliva have been repeatedly reported. However, several contradictions in the existing literature appear on this subject. The present study was performed to definitively establish options for testing adrenocortical function. To the best of our knowledge, this is the first study to evaluate parallel circadian rhythms in salivary and serum cortisol concentrations during a 24-h period. Twenty horses were examined under the same conditions. Blood and saliva samples were taken every 2 h for 24 h to determine the daily changes in cortisol concentrations of saliva and serum at rest and to determine the relationship between salivary and serum cortisol levels. Cosinor analysis of group mean data confirmed a significant circadian component for both serum and salivary cortisol concentrations (P < 0.001 in both cases). The serum cortisol circadian rhythm had an acrophase at 10:50 AM (95% CI, 10:00 AM–11:40 AM), a MESOR of 22.67 ng/mL, and an amplitude of 11.93 ng/mL. The salivary cortisol circadian rhythm had an acrophase at 10:00 AM (95% CI, 9:00 AM–11:00 AM), a MESOR of 0.52 ng/mL, and an amplitude of 0.12 ng/mL. We found a significant but weak association between salivary and serum cortisol concentrations; the Pearson correlation coefficient was 0.32 (P < 0.001). The use of salivary cortisol level as an indicator of hypothalamic-pituitary-adrenal axis activity may be warranted. However, the salivary cortisol levels are more likely to be correlated with free plasma cortisol than with the total plasma cortisol concentration. 相似文献
170.
Luiz Henrique Agra Cavalcante-Silva Ana Carolina de Carvalho Correia José Maria Barbosa-Filho Bagnólia Araújo da Silva Bárbara Viviana de Oliveira Santos Daysianne Pereira de Lira Jéssica Celestino Ferreira Sousa George Emmanuel C. de Miranda Fabiana de Andrade Cavalcante Magna Suzana Alexandre-Moreira 《Marine drugs》2013,11(5):1553-1564
In this work, we investigated the spasmolytic effect of caulerpine, a bisindole alkaloid isolated from marine algae of the Caulerpa genus, on guinea pig ileum. Our findings indicated that caulerpine inhibited phasic contractions induced by carbachol (IC50 = 7.0 ± 1.9 × 10−5 M), histamine (IC50 = 1.3 ± 0.3 × 10−4 M) and serotonin (IC50 = 8.0 ± 1.4 × 10−5 M) in a non-selective manner. Furthermore, caulerpine concentration-dependently inhibited serotonin-induced cumulative contractions (pD′2 = 4.48 ± 0.08), shifting the curves to the right with Emax reduction and slope of 2.44 ± 0.21, suggesting a noncompetitive antagonism pseudo-irreversible. The alkaloid also relaxed the ileum pre-contracted by KCl (EC50 = 9.0 ± 0.9 × 10−5 M) and carbachol (EC50 = 4.6 ± 0.7 × 10−5 M) in a concentration-dependent manner. This effect was probably due to inhibition of Ca2+ influx through voltage-gated calcium channels (CaV), since caulerpine slightly inhibited the CaCl2-induced contractions in depolarizing medium without Ca2+, shifting the curves to the right and with Emax reduction. According to these results, the spasmolytic effect of caulerpine on guinea pig ileum seems to involve inhibition of Ca2+ influx through CaV. However, other mechanisms are not discarded. 相似文献