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排序方式: 共有331条查询结果,搜索用时 15 毫秒
131.
Metal Tolerance, Accumulation and Translocation in Poplar and Willow Clones Treated with Cadmium in Hydroponics 总被引:3,自引:0,他引:3
Massimo Zacchini Fabrizio Pietrini Giuseppe Scarascia Mugnozza Valentina Iori Lucia Pietrosanti Angelo Massacci 《Water, air, and soil pollution》2009,197(1-4):23-34
To evaluate the phytoremediation capability of some poplar and willow clones a hydroponic screening for cadmium tolerance, accumulation and translocation was performed. Rooted cuttings were exposed for 3 weeks to 50 μM cadmium sulphate in a growth chamber and morpho-physiological parameters and cadmium content distribution in various parts of the plant were evaluated. Total leaf area and root characteristics in clones and species were affected by cadmium treatment in different ways. Poplar clones showed a remarkable variability whereas willow clones were observed to be more homogeneous in cadmium accumulation and distribution. This behaviour was further confirmed by the calculation of the bio-concentration factor (BCF) and the translocation factor (Tf). Mean values of all the clones of the two Salicaceae species showed that willows had a far greater ability to tolerate cadmium than poplars, as indicated by the tolerance index (Ti), calculated on the dry weight of roots and shoots of plants. As far as the mean values of Tf was concerned, the capacity of willows to translocate was double that of poplars. On the contrary, the mean values of total BCF in poplar clones was far higher with respect to those in willows. The implications of these results in the selection of Salicaceae clones for phytoremediation purposes were discussed. 相似文献
132.
Spadavecchia C Levionnois O Kronen PW Leandri M Spadavecchia L Schatzmann U 《American journal of veterinary research》2006,67(5):762-769
OBJECTIVE: To investigate effects of isoflurane at approximately the minimum alveolar concentration (MAC) on the nociceptive withdrawal reflex (NWR) of the forelimb of ponies as a method for quantifying anesthetic potency. ANIMALS: 7 healthy adult Shetland ponies. PROCEDURE: Individual MAC (iMAC) for isoflurane was determined for each pony. Then, effects of isoflurane administered at 0.85, 0.95, and 1.05 iMAC on the NWR were assessed. At each concentration, the NWR threshold was defined electromyographically for the common digital extensor and deltoid muscles by stimulating the digital nerve; additional electrical stimulations (3, 5, 10, 20, 30, and 40 mA) were delivered, and the evoked activity was recorded and analyzed. After the end of anesthesia, the NWR threshold was assessed in standing ponies. RESULTS: Mean +/- SD MAC of isoflurane was 1.0 +/- 0.2%. The NWR thresholds for both muscles increased significantly in a concentration-dependent manner during anesthesia, whereas they decreased in awake ponies. Significantly higher thresholds were found for the deltoid muscle, compared with thresholds for the common digital extensor muscle, in anesthetized ponies. At each iMAC tested, amplitudes of the reflex responses from both muscles increased as stimulus intensities increased from 3 to 40 mA. A concentration-dependent depression of evoked reflexes with reduction in slopes of the stimulus-response functions was detected. CONCLUSIONS AND CLINICAL RELEVANCE: Anesthetic-induced changes in sensory-motor processing in ponies anesthetized with isoflurane at concentrations of approximately 1.0 MAC can be detected by assessment of NWR. This method will permit comparison of effects of inhaled anesthetics or anesthetic combinations on spinal processing in equids. 相似文献
133.
The objective of the study was to investigate and assess the impact of trainings on the levels of meat contamination produced
from local livestock slaughter facilities in the North-West region of Somalia (Somaliland). The investigation considered slaughter
facilities where workers had been trained or not. The survey was carried out in four local slaughter facilities. A pre-tested
questionnaire on abattoir hygiene and food safety standards was administered to International Aid Organizations, government
officials, abattoir workers and supervisors. In addition, a total of 320 surface meat swab samples were collected from randomly
selected small ruminant carcasses slaughtered from four purposefully selected local slaughter facilities. The samples were
analyzed at Analabs laboratories in Nairobi, Kenya, for total viable counts, total coliforms count and presence of Salmonella species. Meat contamination risk factors associated with hygiene practices based on training offered or not was identified.
It was noted that slaughter facilities where abattoir workers had not received trainings on minimum meat hygiene standards
and quality assurance systems of good hygiene practices and sanitary standard operating procedures produced carcasses with
high levels of bacterial contamination in comparison with those where workers had received the said trainings. The laboratory
results were in agreement with poor hygiene meat handling practices and lack of compliance with minimum meat hygiene and food
safety standards in Berbera and Burao local livestock slaughter facilities where personnel had not been trained. 相似文献
134.
Filippo Maggi Massimo Bramucci Cinzia Cecchini Maria M. Coman Alberto Cresci Gloria Cristalli Giulio Lupidi Fabrizio Papa Luana Quassinti Gianni Sagratini Sauro Vittori 《Fitoterapia》2009,80(6):313-319
Essential oil from flowers (FL) and vegetative parts (VP) of Achillea ligustica (Asteraceae), naturalized after cultivation in central Italy, was investigated by GC–FID and GC–MS. The most abundant components were linalool, viridiflorol, β-pinene, 1,8-cineole and terpinen-4-ol. The antioxidant assays (DPPH and ABTS radical scavenging assays, and β-carotene bleaching test) demonstrated a moderate activity of essential oils. The antimicrobial activity was evaluated by the broth micro-dilution method on 6 microbial strains and showed to be quite strong against the cariogenic Gram-positive Streptococcus mutans, suggesting that this essential oil could be a valid candidate for anti-cariogenic formulations. Moderate cytotoxic activity was observed in assays on four tumour cell lines by MTT assay. 相似文献
135.
Giorgio Marchesini Lorenzo Serva Maria Chinello Matteo Gazziero Sandro Tenti Massimo Mirisola Elisabetta Garbin Barbara Contiero Daniel Grandis Igino Andrighetto 《Grass and Forage Science》2019,74(3):415-426
The aim of this study was to assess the effects of earliness (according to FAO class), maturity stage at harvest and environmental conditions on the ensilability of maize hybrids described by their fermentation products and by a fermentation quality index (FQI). Maize hybrids belonging to early (n = 14) and late (n = 15) FAO classes were grown in low, medium and high potential yield areas and harvested at an early (EH), medium (MH) and late maturity stage (LH), that is, at 1/3, 2/3 and 5 d after the 2/3 milk line stage, respectively, according to a split‐plot design. Upon harvest, each sample (n = 522) was analysed for dry matter (DM) and water‐soluble carbohydrates (WSC) before being ensiled in vacuum‐packed bags (n = 1,044). After 60 days of conservation, samples were analysed for DM and fermentation products. In the pre‐ensiling phase, DM was higher in early hybrids (p = .001), low yield areas (p < .001) and at LH maturity (p < .001), whereas WSC contents were higher in early hybrids (p < .001), medium yield areas (p < .001) and at EH maturity (p < .001). With regard to silages, early hybrids had a higher FQI (p < .001), which was highest in areas with a high yield potential (p < .01) and at EH maturity (p < .01). Late hybrids proved to be better suited for low yield areas compared with early hybrids (p < .01) and had a higher FQI at EH and MH than at LH maturity (p < .01). 相似文献
136.
Giorgi C Ito K Lin HK Santangelo C Wieckowski MR Lebiedzinska M Bononi A Bonora M Duszynski J Bernardi R Rizzuto R Tacchetti C Pinton P Pandolfi PP 《Science (New York, N.Y.)》2010,330(6008):1247-1251
The promyelocytic leukemia (PML) tumor suppressor is a pleiotropic modulator of apoptosis. However, the molecular basis for such a diverse proapoptotic role is currently unknown. We show that extranuclear Pml was specifically enriched at the endoplasmic reticulum (ER) and at the mitochondria-associated membranes, signaling domains involved in ER-to-mitochondria calcium ion (Ca(2+)) transport and in induction of apoptosis. We found Pml in complexes of large molecular size with the inositol 1,4,5-trisphosphate receptor (IP(3)R), protein kinase Akt, and protein phosphatase 2a (PP2a). Pml was essential for Akt- and PP2a-dependent modulation of IP(3)R phosphorylation and in turn for IP(3)R-mediated Ca(2+) release from ER. Our findings provide a mechanistic explanation for the pleiotropic role of Pml in apoptosis and identify a pharmacological target for the modulation of Ca(2+) signals. 相似文献
137.
Daniele Masseroni Arianna Facchi Marco Romani Enrico Antonio Chiaradia Olfa Gharsallah Claudio Gandolfi 《Paddy and Water Environment》2015,13(4):405-424
About 90 % of the global rice production takes place in Asia, while European production is quantitatively modest. Italy is the Europe’s leading producer, with over half of total production concentrated in a large, traditional paddy rice area in the north of the country. High irrigation requirement for continuous flooding encourages the adoption of water saving techniques. In 2013, an intense monitoring activity was conducted on two fields characterized by continuous flooding and intermittent irrigation regimes, with the aim of comparing their agronomical and hydrological effects, including their influence on the energy balance. An eddy covariance station was installed on the levee between the two fields, to monitor latent (LE) and sensible (H) heat fluxes as a function of wind direction. Additionally, the fields were instrumented with net radiometers, soil heat flux (G) plates, thermistors, tensiometers, and multilevel moisture probes. Three footprint models were applied to determine position and size of the footprint area at each monitoring time step, providing similar results. Two half-hourly turbulent fluxes datasets were obtained, one for each irrigation regime, each one comprising about 10 % of the daytime time steps over the agricultural season. The reliability of the monitoring performed with a single EC station was confirmed by the energy balance closure (H + LE versus Rn-G), showing an imbalance lower than 10 % for both the regimes. A detailed analysis of the effect of the storage terms on the ground heat flux estimation and a more thorough analysis of the radiation balance for the two plots were also performed. 相似文献
138.
Pinelli P Ieri F Vignolini P Bacci L Baronti S Romani A 《Journal of agricultural and food chemistry》2008,56(19):9127-9132
In the present study the phenolic composition of leaves, stalks, and textile fiber extracts from Urtica dioica L. is described. Taking into account the increasing demand for textile products made from natural fibers and the necessity to create sustainable "local" processing chains, an Italian project was funded to evaluate the cultivation of nettle fibers in the region of Tuscany. The leaves of two nettle samples, cultivated and wild (C and W), contain large amounts of chlorogenic and 2- O-caffeoylmalic acid, which represent 71.5 and 76.5% of total phenolics, respectively. Flavonoids are the main class in the stalks: 54.4% of total phenolics in C and 31.2% in W samples. Anthocyanins are second in quantitative importance and are present only in nettle stalks: 28.6% of total phenolics in C and 24.4% in W extracts. Characterization of phenolic compounds in nettle extracts is an important result with regard to the biological properties (antioxidant and antiradical) of these metabolites for their possible applications in various industrial activities, such as food/feed, cosmetics, phytomedicine, and textiles. 相似文献
139.
Pedotransfer functions (PTFs) make use of routinely surveyed soil data to estimate soil properties but their application to soils different from those used for their development can yield inaccurate estimates. This investigation aimed at evaluating the water retention prediction accuracy of eight existing PTFs using a database of 217 Sicilian soils exploring 11 USDA textural classes. PTFs performance was assessed by root mean square differences (RMSD) and average differences (AD) between estimated and measured data. Extended Nonlinear Regression (ENR) technique was adopted to recalibrate or develop four new PTFs and Wind’s evaporation method was applied to validate the effectiveness of the relationships proposed. PTFs evaluation resulted in RMSD and AD values in the range 0.0630–0.0972 and 0.0021–0.0618 cm3 cm–3, respectively. Best and worst performances were obtained respectively by PTF-MI and PTF-ZW. ENR allowed to recalibrate PTF-MI and PTF-ZW with improvements of RMSD (0.0594 and 0.0508 cm3 cm–3) and to develop two relationships that improved RMSD by 75–78% as compared to PTF-MI. The results confirmed the potential of ENR technique in calibrating existing PTFs or developing new ones. Validation conducted with an independent dataset suggested that recalibrated/developed PTFs represent a viable alternative for water retention estimation of Sicilian soils. 相似文献
140.
Improvement of grazing-tolerance in lucerne ( Medicago sativa L.) is an objective of interest worldwide for the acknowledged potential of this species in pastures. A breeding programme applied standard methods of the selection for this trait, which implies continuous stocking and intensive grazing, to germplasm preliminarily selected for reportedly positive morphological attributes (large and deep crowns; non-erect growth habit). In this study six experimental cultivars, originating from this programme, and three check varieties were evaluated. Grazing tolerance was assessed under continuous sheep stocking for 2 years. Herbage yield in 3 years and seed yield (in the second year) were also evaluated in distinct and contiguous sub-experiments. One experimental cultivar had a prostrate habit, two were semi-prostrate, and three were semi-erect. Under grazing, five of them showed final persistence similar to, or better than, that of the tolerant check variety adopted in the standard test. In particular, the prostrate experimental cultivar (termed Camporegio) had remarkable persistence, although associated with low vigour, associated with the introgression of M. sativa ssp. falcata into its parentage. A semi-erect cultivar (termed Verbena) possessed a good balance between grazing tolerance, potential dry-matter yield and seed yield. 相似文献