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841.
Massimiliano Renna Maria Gonnella Sofia Caretto Giovanni Mita Francesco Serio 《Genetic Resources and Crop Evolution》2017,64(1):205-216
Sea fennel (Crithmum maritimum L.) is a perennial halophyte species typical of coastal ecosystems, used fresh in traditional cuisine and folk medicine due to its sensory properties and a good content of healthy compounds. Although considered as a promising biosaline crop, this halophyte is underutilized for commercial cultivation possibly due to a shortage of its consumer demand. For promoting a full exploitation of this species, a new food product was obtained by drying sea fennel using different treatments (air-drying, microwave-drying, microwave-assisted air-drying and freeze-drying). Water activity, essential oil content, chlorophylls, surface colour, colouring power and sensory evaluation were analyzed. All drying treatments allow to obtain a good water activity but significantly reduced the content of essential oils and chlorophylls. Freeze-drying and microwaving preserved the surface colour parameters more than other drying treatments, while freeze-drying gave the product the best colouring power. Based on sensory analysis, microwave-drying, microwave-assisted air-drying and freeze-drying showed the highest scores among the drying methods. Taken together the results indicate that microwaving and freeze-drying are optimal for preserving qualitative traits, including organoleptic properties, in dried sea fennel for food use. Furthermore, dried sea fennel can be usefully exploited in human food not only for its aromatic traits but also for its food colouring power like other plant derived natural colorants. It could be concluded that this underutilized crop could play a better role for making up a sustainable food production system. 相似文献
842.
An isotopic model (NISOTOP) has been developed to investigate the effect of the addition to soil of xenobiotics on urea hydrolysis, N mineralization and immobilization, nitrification and plant uptake of nitrogen in a soil-plant system, after addition of 15N enriched compounds. Therationale of the model follows from the errors in %15N abundance (15N D) and N concentration (CN) determinations which cause high variability coefficients in the calculation of the amount of nitrogen present in the different compounds derived from the added 15N enriched urea. The extent of these errors, besides depending on CN and 15N D errors, will also depend on natural 15N and 15N of the added compound, and therefore on the experimental conditions. The model is described by 18 first-order differential equations and is numerically solved by Euler's method with a time increment of 0.01 day. As an illustration, the model is applied to the effect of phenanthrene, chrysene and benzo(a)pyrene to a soil-plant system, following the addition of 15N-urea. These compounds have been chosen as examples of molecules having 3, 4 and 5 fused aromatic rings and are hereafter collectively referred to as PAHs. PAHs at the rate of 2 mg kg-1 soiland 15N-urea at the rate of 166.7 mg N kg-1 soil were added to wheat pots. At harvesting (after 14 days from plantation) the dry matter yield, the total N content and the N concentration of the wheat seedlings were not statistically affected by addition of the PAHs (P = 0.05). The efficiency of N uptake, that is the percentage of fertilizer taken up by the plants at harvesting in the absence of PAHs was 47.3%, while it was 11.7, 15.2 and 14.8% in the presence of phenanthrene, chrysene and benzo(a)pyrene,respectively. The computation of the first-order rate constants of the N transformations showed that N mineralization, nitrification and N-uptake were affected by the addition of phenanthrene, chrysene and benzo(a)pyrene, whilst benzo(a)pyrene inhibited urea hydrolysis more than phenanthrene and chrysene. 相似文献
843.
J. A. C. de Souza-Dias P. Russo J. A. Betti L. Miller S. A. Slack 《American Journal of Potato Research》1999,76(4):209-213
This report describes a simple, rapid and inexpensive procedure for sampling large numbers of dormant tubers for analysis of potato leafroll luteovirus (PLRV) infection. The procedure uses a common electric drill to simultaneously remove and macerate tuber-eye samples for detection of PLRV by the enzyme-linked immunosorbant assay (ELISA) and the polymerase chain reaction (PCR). By using these sampling and analysis approaches, 19 of 20 different PLRV isolates were detected in dormant tubers from plants with primary infections. Results from the dormant tuber analysis, were verified by planting the tubers and testing leaf tissue by ELISA and PCR. Similar sampling and testing done on healthy dormant tubers and sprouts from the tubers consistently gave negative results as expected. 相似文献
844.
João Costa Filho Mônica Yumi Tsuzuki Giovanni Lemos de Mello Luiz Cláudio Miletti Karim Hahn Lüchmann Carlos André da Veiga Lima-Rosa 《Journal Of Applied Aquaculture》2017,29(3-4):199-206
We investigated the growth of juvenile common snook (Centropomus undecimalis) reared at 25°C and 28°C and salinities of 0.3, 15, and 32 g L?1. Total length, weight, RNA/DNA, and protein/DNA ratios were determined after 90 days of experiment. Higher growth was observed at 28ºC compared with 25°C, at the same salinity. At 28°C and 15 g L?1 salinity, the weight (25.14 g) of juveniles was twice that of the juveniles reared at the lower temperature. At different salinities, only higher temperature affected growth, with higher weight values obtained at 15 g L?1 in comparison with 0.3 and 32 g L?1. Length was similar at 0.3 and 15 g L?1. The RNA/DNA ratio was greater in juveniles reared at a salinity of 15 g L?1 when compared with 0.3 and 32 g L?1. This study shows that the combination of higher temperature and intermediate salinity promotes better growth of common snook juveniles. 相似文献
845.
De-Hai Xu Victor S Panangala Vicky L van Santen Kevin Dybvig Jason W Abernathy Phillip H Klesius Zhanjiang Liu & Riccardo Russo 《Aquaculture Research》2009,40(16):1884-1892
Ichthyophthirius multifiliis (Ich), a ciliated protozoan parasite of fish, expresses surface antigens (i-antigens), which react with host antibodies that render them immobile. The nucleotide sequence of an i-antigen gene of I. multifiliis strain ARS-6 was deduced. The predicted protein of 47 493 Da is comprised of 460 amino acids (aa's) arranged into five imperfect repeats with periodic cysteine residues with the structure: CX(19)20 CX2 CX16−27 CX2 CX20(21) CX3 . The N-terminal aa's typify a signal peptide motif while a stretch of C-terminal aa's resemble a glycosyl–phosphatidyl–inositol (GPI)-anchor addition site. The degree of deduced i-antigen aa sequence identity of strain ARS-6 (GenBank accession # ACH87654 and # ACH95659) with other I. multifiliis i-antigen sequences present in GenBank ranges from 99% to 36% identity with 52 kDa i-antigens of I. multifiliis strain G5 (accession #s AAK94941 and AAK01661 respectively). Immunoblot analysis of i-antigens following exposure of I. multifiliis theronts to catfish anti- I. multifiliis immune serum did not show any appreciable alteration in i-antigen expression. The mechanism that regulates i-antigen expression in I. multifiliis remains a puzzling question. 相似文献
846.
Giovanni Bearzi Nino Pierantonio Silvia Bonizzoni Giuseppe Notarbartolo di Sciara Massimo Demma 《水产资源保护:海洋与淡水生态系统》2010,20(6):644-654
- 1 The view that whales are malicious monsters has been pervasive throughout history. Conversely, the idea that these animals experience suffering has emerged only recently. One way of investigating perceptual, as well as behavioural, shifts is assessing general public reactions to mortality events involving wild, rare and charismatic animals.
- 2 Here, the responses of 118 individuals to questions regarding the mass stranding of seven sperm whales (Physeter macrocephalus) along the Adriatic Sea coast of Italy in December 2009 are reported through interviews taken at the stranding site and in the direct proximity of the dead animals.
- 3 When asked why the whales were stranded, 44.1% of the respondents suggested anthropogenic causes and 21.2% non‐anthropogenic. The remaining 34.7% mentioned a generic ‘disorientation’ or stated they did not know. When asked how they felt about the whales, 68.6% expressed feelings of compassion or care towards the animals. Clearly non‐compassionate attitudes accounted for only 4.1% of the sample. Finally, 21.2% expressed feelings that were ambiguous in terms of being suggestive of compassionate or non‐compassionate attitudes, including 11.9% amazement, 4.2% deprecation and 5.1% powerlessness.
- 4 These results are in stark contrast with information obtained from accounts of similar events that have occurred in historical times, up until the first half of the 20th century. For centuries, responses to cetacean live strandings—typically including killing and harming of the animals—were either utilitarian or characterized by feelings including fear and a desire to ‘subjugate the beast’, with no apparent concern for their suffering and death.
- 5 It is concluded that attitudes towards whales—today strikingly revolving around sadness, compassion and a sense of loss—have changed dramatically over time, with a steep turnaround in the 1970/1980s. Full appreciation of the ongoing evolution in public perception can channel marine conservation efforts and assist in the design of response strategies to marine mammal strandings. Copyright © 2010 John Wiley & Sons, Ltd.
847.
- Group membership is a key attribute of animal societies and central to the study of social structure in several taxa. However, social structure analyses are sensitive to the way data are collected and associations defined.
- In this study, a time–space method was used to investigate the social structure of common bottlenose dolphins Tursiops truncatus observed and photographed across 7 years in the semi-enclosed Gulf of Corinth, Greece. Instead of adopting traditional group definitions, individuals were considered as being members of the same group if photographed within a specific time and space window. This approach can be applied post hoc across studies and can offer advantages under challenging sampling conditions (e.g. when dealing with groups spread over vast areas or when group membership is otherwise hard to assess).
- Dolphins were mostly found around coastal cage aquaculture facilities farming European sea bass Dicentrarchus labrax and gilthead seabream Sparus aurata.
- Dolphins formed clusters largely or entirely composed of individuals of the same sex, suggestive of sex-based homophily. Habitat partitioning was not detected: there was substantial spatial overlap among dolphin clusters, with all individuals using a relatively small area in the northern portion of the Gulf, where most of the productive fish farms were located. Associations between females were stronger than those between males, and daughters tended to stay in the group of their mothers.
- Sex-based social clustering may allow females and calves to limit interactions with potentially aggressive males, while individuals of both sexes benefit from prey concentrated around fish farms.
- Adaptation to foraging around farms can result in trade-offs between the costs and benefits of nourishment and social interaction. This may have both positive or negative effects on the animals that should be considered in the context of ensuring their favourable conservation status.