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1.
Pratap Chandra Das Joykrushna Jena Bibhudatta Mishra Bikash Kumar Pati 《Journal of the World Aquaculture Society》2012,43(1):128-134
Impact of aeration on growth of silver barb, Puntius gonionotus during fingerling rearing was studied through a 100‐d rearing experiment conducted in 18 concrete tanks of 50 m2 (10 × 5 × 1.2 m) size. Fry (0.74 ± 0.27 g, 35 ± 6 mm) were stocked in the experimental tanks at three stocking densities (25, 50, and 75 fry/m2) and were evaluated with and without provision of 6 h (2400–0600 h) of night time aeration. Aeration resulted in higher pH and dissolved oxygen regime and increased fingerling length and weight. The results suggest a rearing density of 75/m2 to be ideal for rearing fry to fingerling of this species when aeration is provided, whereas, under non‐aerated condition, rearing the fry to fingerling stage at 50/m2 was found advantageous over those at 25 and 75/m2. 相似文献
2.
Vulnerability of xylem to loss of hydraulic conductivity caused by drought-induced cavitation was determined for three riparian cottonwood species in Lethbridge, Alberta: Populus deltoides Bartr., P. balsamifera L., and P. angustifolia James. These species suffered 50% loss of hydraulic conductivity in one-year-old stem segments when xylem pressure potential fell to -0.7 MPa for P. deltoides and -1.7 MPa for P. balsamifera and P. angustifolia, making them the three most vulnerable tree species reported so far in North America. The possible contribution of drought-induced xylem dysfunction to the decline of riparian ecosystems in dammed rivers is discussed. 相似文献
3.
Hydraulic architecture parameters, water relation parameters and wood anatomy were studied in roots and shoots of the flood-tolerant tree Annona glabra L. on Barro Colorado Island, Panama. Hydraulic conductivity, leaf specific conductivity, and Huber value were similar to the corresponding values for tree species living in non-flooded habitats. The vulnerability of stems to loss of hydraulic conductivity resulting from embolism was low (50% loss of conductivity at -3.3 MPa). The lowest leaf water potential measured in the field was about -1.0 MPa, indicating that A. glabra has a large margin of safety from embolism, which may provide protection against rare drought events, or may be an adaptation to brackish mangrove habitats. Low absolute conductivity of roots was compensated for by an increase in the number of roots. More than two-thirds of whole-plant resistance to water flow was located in the roots. 相似文献
4.
In teleosts, as in other vertebrates, the secretion of pituitary gonadotropin (GTH) is mediated by the hypothalamic decapeptide, gonadotropin-releasing hormone (GnRH). Recent findings in teleosts indicate that GnRH receptors are not restricted to the pituitary gonadotropes and are also associated with somatotropes as well as being present in a number of other tissues. In the present study, we provide novel information on GnRH binding in a number of extrapituitary tissues in goldfish. However, we do not intend to provide full characterization of GnRH binding sites in various extrapituitary tissues in goldfish as this would clearly be outside the scope of this paper. In this study we examined GnRH binding in a number of extrapituitary tissues in goldfish and observed specific binding in ovary, testis, brain, liver and kidney. No specific GnRH binding was observed in muscle, skin, gut, gill and heart. In general, the present findings together with the results of other studies carried out in our laboratory demonstrate that mature goldfish ovary and testis contain two classes of GnRH binding sites, high affinity/low capacity and low affinity/high capacity sites with binding characteristics similar to those of the pituitary GnRH receptors. The brain of goldfish was also found to contain two classes of GnRH binding sites, a super-high affinity/low capacity and a low affinity/high capacity sites. Furthermore, study of goldfish liver and kidney demonstrated the presence of a single class of GnRH binding sites with characteristics different from those of pituitary, ovary, testis and brain. Overall, it is evident that goldfish contains a family of GnRH binding sites which can be classified into four groups based on binding affinities: 1) A class of high affinity binding sites present in the pituitary, ovary and testis, 2) a class of super high affinity sites so far only detected in the brain, 3) a class of intermediate-affinity GnRH binding sites in the liver and kidney, and 4) a class of low affinity binding sites present in all the tissues containing specific GnRH binding sites except for liver and kidney. 相似文献
5.
Pati S Quinto M Palmisano F Zambonin PG 《Journal of agricultural and food chemistry》2004,52(15):4638-4642
A fast-response and interference-free amperometric biosensor based on choline oxidase immobilized onto an electropolymerized polypyrrole film for flow injection determination of choline in milk, milk powder, and soy lecithin hydrolysates is described. The sensor displayed an Imax value of 1.9 +/- 0.2 microA and an apparent Michaelis-Menten constant, k'M, equal to 1.75 +/- 0.07 mM. Detection limits of 0.12 microM could be obtained. Because even a slight deterioration of the anti-interference membrane can adversely affect measurement accuracy, a real time monitoring of the biosensor selectivity has been achieved by a dual Pt electrode flow-through cell where the enzyme modified electrode is coupled to an enzyme-free electrode in a parallel configuration. Finally, bracketing technique (alternate injections of sample and standards) allows a two-point calibration to be performed in real-time, correcting for any drift in sensor response. 相似文献
6.
Sajal Pati Biplab Pal Shrikant Badole Biswapati Mandal 《Communications in Soil Science and Plant Analysis》2016,47(3):284-290
A field experiment was conducted to study the effect of silicon (diatomaceous earth, DE) fertilization on growth, yield, and nutrient uptake of rice during the kharif season of 2012 and 2013 in the new alluvial zone of West Bengal, India. Results showed that application of silicon significantly increased grain and straw yield as well as yield-attributing parameters such as plant height (cm), number of tillers m?2, number of panicle m?2, and 1000-grain weight (g) of rice. The greatest grain and straw yields were observed in the treatment T6 (DE at 600 kg ha?1 in combination with standard fertilizer practice (SFP). The concentration and uptake of silicon, nitrogen (N), phosphorus (P), and potassium (K) in grain and straw were also greater under this treatment compared to others. It was concluded that application of DE at 600 kg ha?1 along with SFP resulted increased grain, straw, and uptake of NPK. 相似文献
7.
Jairo Patiño Juana M. González-Mancebo José M. Fernández-Palacios José R. Arévalo Alfredo Bermúdez 《Annals of Forest Science》2009,66(6):609-609
8.
Leticia Torres Carl E. Orazio Paul H. Peterman Reynaldo Patiño 《Fish physiology and biochemistry》2013,39(5):1115-1128
Little is known about the effects of brominated flame retardants in teleosts and some of the information currently available is inconsistent. This study examined effects of dietary exposure to 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) on thyroid condition, body mass and size, and gonadal development of zebrafish. Pubertal, 49-day-old (posthatch) fish were fed diets without BDE-47 (control) or with 1, 5 or 25 μg/g BDE-47/diet. Treatments were conducted in triplicate 30-L tanks each containing 50 zebrafish, and 15 fish per treatment (5 per tank) were sampled at days 40, 80 and 120 of exposure. Measurements were taken of body mass, standard length, head depth and head length. Sex (at 40–120 days of exposure), germ cell stage (at 40 days) and thyroid condition (at 120 days; follicular cell height, colloid depletion, angiogenesis) were histologically determined. Whole-body BDE-47 levels at study completion were within the high end of levels reported in environmentally exposed (wild) fishes. Analysis of variance was used to determine differences among treatments at each sampling time. No effects were observed on thyroid condition or germ cell stage in either sex. Reduced head length was observed in females exposed to BDE-47 at 80 days but not at 40 or 120 days. In males, no apparent effects of BDE-47 were observed at 40 and 80 days, but fish exposed to 25 μg/g had lower body mass at 120 days compared to control fish. These observations suggest that BDE-47 at environmentally relevant whole-body concentrations does not affect thyroid condition or pubertal development of zebrafish but does affect growth during the juvenile-to-adult transition, especially in males. 相似文献
9.
Fiz da Costa Susana Nóvoa Justa Ojea Dorotea Martínez‐Patiño 《Aquaculture Research》2013,44(12):1926-1939
This article reports on the changes in gross biochemical and fatty acid composition of the razor clam Ensis arcuatus larvae throughout development. Protein was the largest component of dried larval tissues. The energy required for embryogenesis in E. arcuatus oocytes was obtained from stored proteins and carbohydrates, while total lipids increased significantly. Lipids and carbohydrates have an important role as energy contributors from day 1 to day 8. During larval development the strategy was to indistinctly store energy reserves (protein, lipid and carbohydrate) to surpass metamorphosis. During embryonic development there was a gain in fatty acids of neutral and polar lipids. A depletion of fatty acids in neutral lipids was observed from day 1 to day 8 in E. arcuatus larvae, mainly due to the decrease in 16:0 and EPA. NMID fatty acids were present in amounts similar to those of some PUFAs in polar lipids, especially 22:2NMID. 相似文献
10.
Alfredo Manuel Bermúdez José María Fernández-Palacios Juana María González-Mancebo Jairo Patiño José Ramón Arévalo Rüdiger Otto Juan Domingo Delgado 《Annals of Forest Science》2007,64(1):109-119
We analyzed a post-clearcut chronosequence (0.5 to 60 years after harvesting) in the laurel forest of La Palma island (Canarian Archipelago) to determine the recovery of the stands with respect to species composition, richness, life strategies and structural parameters of the canopy. Multivariate analysis showed that exotic species, as well as annual ruderal species were confined to early-successional stages, while native perennials, typical of laurel forests, dominated the late-successional stages. Total species richness decreased significantly with time after clear-cutting. The relative fast recovery of understory native species may be due to low forest floor disturbance during harvesting. Shade-intolerant pioneer, pioneer-remnant and shade-tolerant late-successional species were the main life strategies of native tree species. Most structural parameters showed a continuous and monotonic increase (basal area, biomass) or decrease (density, percentage of photosynthetic biomass) during succession. Once clear-cutting, here performed with an interval of 8 years, is abandoned, the recovery of the laurel forest seems possible due to careful logging that protects the soil and a rapid asexual regeneration of native tree species, revealing this to be a sustainable management practice. 相似文献