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排序方式: 共有125条查询结果,搜索用时 109 毫秒
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Patricia Flores Damián Poggi Stella Maris García Marcela Catraro 《International Journal of Fruit Science》2017,17(1):29-40
The objective of this work was to quantify changes in the germination capacity of Juglans nigra seeds following storage and then artificial stratification. Seeds were stored at 5 and –20 °C under 5% and 14% internal moisture content (IMC) for 0, 8, 10, and 12 months under conditions with oxygen or under vacuum. Germination percentage (GP) was affected by storage temperature, IMC, and storage period. Seeds stored with 5% IMC succeeded in germinating regardless of the temperature. Seeds stored with 14% IMC did not germinate (–20 °C) or germinated during storage (5 °C). The GP was reduced with the time of storage in seeds at –20 °C and 5% IMC and this effect was avoided in storage under vacuum. In conclusion, the germination capacity of black walnut seeds did not change for up to 12 months at low above-zero temperature and low IMC (5 °C, 5% IMC), being the most cost-effective alternative for long-term storage of black walnut seeds in commercial nurseries. Vacuum storage avoided the decrease of around 50% in average germination capacity of seeds stored for a year at –20 °C. 相似文献
3.
Ortuño A Castellà J Marco I Ruiz M Lavín S 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(5):253-254
Ungulates are involved in the epidemiology of Borreliosis as maintenance hosts for vector tick species. We evaluated the prevalence of antibodies to Borrelia burgdorferi sensu lato in two different populations of southern chamois in Spain. Forty-six sera (40.4%) were positive at titres >/=1 : 64 using an indirect immunofluorescence assay (IFAT). 相似文献
4.
Romà Ogaya Anna Escolà Daijun Liu Adrià Barbeta Josep Peñuelas 《Journal of Sustainable Forestry》2020,39(4):365-378
ABSTRACTA natural holm oak forest was selectively thinned to test thinning as a tool to reduce tree mortality, increase productivity, and reverse the recent regression of the dominant species (Quercus ilex) induced by climate change. Thinning increased aboveground productivity and reduced stem mortality in this Mediterranean forest during four years just after thinning, contributing to the maintenance of forest functioning under changing climatic conditions. Q. ilex was the only species positively affected by the thinning: stem growth increased for all stem sizes, and mortality was significantly lower in thinned plots. On the contrary, mortality rates of Phillyrea latifolia and Arbutus unedo were not significantly lower. Stem growth increased for P. latifolia only in the smallest stem-size class. Our results highlight the suitability of selective thinning for improving the forest productivity and ensuring the conservation of Mediterranean coppices. Other benefits of selective thinning, such as a decrease in the risk of fire dispersion and an increase in the water supply for human populations, are also discussed. 相似文献
5.
Vocalizations During Electroejaculation in Anaesthetized Adult and Young Pampas Deer (Ozotoceros bezoarticus) Males
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The aim of this study was to characterize the vocalizations produced during electroejaculation under general anaesthesia in pampas deer males and to determine whether the characteristics of those vocalizations differ in adult and young pampas deer males. Electroejaculation was applied to 13 adults (AM) and 13 young (YM) males under general anaesthesia. Vocalizations were digitally recorded, and the number and duration of vocalizations, the latency in relation to each voltage, the total time vocalizing, and the structure of the fundamental frequency (F0) [initial frequency (Fstart), maximal frequency (Fmax), minimal frequency (Fmin) and final frequency (Fend)] were analysed. No male vocalized with 0 V; the number of animals that vocalized increased at 2 and 3 V and increased again at 4, 5 and 6 V (p < 0.05). The latency time from the beginning of each series (each voltage) decreased until 4 V (p < 0.01). The number of vocalizations/voltage increased from 4 V (p < 0.05). The length of each vocalization and the total time during which animals vocalized were greater in YM than AM (p = 0.02 and p = 0.01, respectively). Similarly, the fundamental frequencies were higher in YM than AM (p ≤ 0.05). Overall, we concluded that the vocalizations emitted during electroejaculation in pampas deer under general anaesthesia are related to the voltage applied during the process. Young males vocalize more time, probably due to a greater sensibility to the electric stimulation. The differences in the characteristics of the vocalizations between adult and young males may be related to the anatomic differences in the neck of adult or young males. 相似文献
6.
María Fuentes-Rubio José J. Cerón Carlos de Torre Damián Escribano Ana M. Gutiérrez Fernando Tecles 《Canadian journal of veterinary research》2014,78(2):127-132
The purpose of this research was to study changes in the salivary proteome of healthy pigs in stressful situations to identify any potential new salivary biomarker of stress. Three groups of animals were subjected to 3 stress models: snaring restraint followed by simulated sampling of vena cava blood; brief transport by road; and restriction of movement in a digestibility cage. Saliva was obtained from each animal before and 15 and 30 min after the induction of stress. The samples from the animals that showed the greatest increase in salivary cortisol concentration were pooled and run on 2-dimensional gels. Coomassie Brilliant Blue R-250 was used for spot detection and mass spectrometry for spot identification. Statistical analyses showed that 2 proteins had significant differences in expression before and after the induction of stress. These proteins were identified as odorant-binding protein and fragments of albumin. Further studies will be necessary to confirm the value of using these proteins as salivary biomarkers of stress in pigs. 相似文献
7.
Damián Escribano Ana M. Gutiérrez María Fuentes-Rubio José J. Cerón 《Veterinary journal (London, England : 1997)》2014,199(3):355-359
Salivary chromogranin A (CgA) is considered to be a biomarker of activation of the sympatho-adrenomedullary system, and has recently been proposed as a useful indicator of the acute stress response in pigs. The aim of the present study was to determinate whether salivary CgA concentrations in healthy growing pigs exhibits any circadian pattern during the daytime, and to evaluate its stability under different storage conditions. A total of 80 pigs (40 in spring and another 40 in autumn) of two different ages and genders were used. To establish the circadian pattern, saliva samples were collected at 07.00, 11.00, 15.00 and 19.00 h on two consecutive days. Pooled samples were used for the stability study and were measured on the day of sampling and periodically for up to 360 days later. Samples were stored at 4 °C, ?20 °C or ?80 °C and the effect of repeated freezing and thawing was also evaluated.No circadian pattern was detected for salivary CgA in either season and there were no significant effects of gender or age. However, mean salivary CgA concentrations were significantly higher (P < 0.0001) in the pigs sampled in autumn, compared to those sampled in the spring. Short term storage at 4 °C is recommended for up to 2 days, whereas frozen samples can be stored for 1 year at ?20 °C or ?80 °C, without substantial reduction in CgA values. In addition, samples can be frozen and thawed up to seven times without significant loss of the biomarker. 相似文献
8.
Girbau-Solà T López-Barajas M López-Tamames E Buxaderas S 《Journal of agricultural and food chemistry》2002,50(20):5600-5604
The foam properties of sparkling wines (Cava) made from two red autochthonous grape varieties, Trepat and Monastrell, and coupages, including different percentages of them, were studied during second fermentation and aging. The effect of second fermentation on foam gave the highest decreases when the base wines had the highest foam values, while gave the lowest decreases or even increases for the base wines with the lowest foam characteristics. However, the greater the HM and Sigma of the base wine, the greater the foam values of the sparkling wine. Base wine determinations for quality control in cellars could provide information about future sparkling wine foaming. Acidity parameters, ethanol, sulfur, and polysaccharides contents were correlated to foam characteristics in the sparkling wines. In terms of color and foaming, wines made from the red varieties Trepat and Monastrell blended with white variety wines could be appropriate for elaborating "blanc de noirs" sparkling wines. 相似文献
9.
Béjà O Aravind L Koonin EV Suzuki MT Hadd A Nguyen LP Jovanovich SB Gates CM Feldman RA Spudich JL Spudich EN DeLong EF 《Science (New York, N.Y.)》2000,289(5486):1902-1906
Extremely halophilic archaea contain retinal-binding integral membrane proteins called bacteriorhodopsins that function as light-driven proton pumps. So far, bacteriorhodopsins capable of generating a chemiosmotic membrane potential in response to light have been demonstrated only in halophilic archaea. We describe here a type of rhodopsin derived from bacteria that was discovered through genomic analyses of naturally occuring marine bacterioplankton. The bacterial rhodopsin was encoded in the genome of an uncultivated gamma-proteobacterium and shared highest amino acid sequence similarity with archaeal rhodopsins. The protein was functionally expressed in Escherichia coli and bound retinal to form an active, light-driven proton pump. The new rhodopsin exhibited a photochemical reaction cycle with intermediates and kinetics characteristic of archaeal proton-pumping rhodopsins. Our results demonstrate that archaeal-like rhodopsins are broadly distributed among different taxa, including members of the domain Bacteria. Our data also indicate that a previously unsuspected mode of bacterially mediated light-driven energy generation may commonly occur in oceanic surface waters worldwide. 相似文献
10.
Factors that contribute to the mycoparasitism stimulus in Trichoderma atroviride strain P1
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Woo S L Formisano E Fogliano V Cosenza C Mauro A Turrà D Soriente I Ferraioli S Scala F Lorito M 《浙江大学学报(农业与生命科学版)》2004,30(4):421-421
Trichoderma atroviride strain P1 has been used extensively to study the mycoparasitic mechanisms in the interaction between plant pathogenic host and beneficial antagonistic fungi. Mutants of P1 containing the green fluorescent protein (gfp) or glucose oxidase (gox) reporter systems and different inducible promoters (from the exochitinase nag1 gene, or the endochitinase ech42 gene of P1) were used to determine the factors that activate the biocontrol gene expression cascade in the antagonis… 相似文献