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1.
Journal of Soils and Sediments - Dissipation of pharmaceutical compounds entered into the natural environment is an important process minimizing the adverse effects on the living organisms. The aim...  相似文献   
2.
  1. Although the frequency of occurrence of plastic ingestion in the large-sized dolphinfish and tunas taken by the Hawai'i longline fishery is very low (frequency of occurrence < 5% of sampled individuals), the ingestion of plastic in smaller-sized specimens caught with pole-and-line gear by commercial and recreational fishers has not been investigated.
  2. This study examined ingestion of >0.25 mm marine plastic debris (MPD) by four predatory fish species caught by commercial fishers around the Main Hawaiian Islands, and documented ingestion in three species: 85.7% of albacore tuna (n = 7), 40.0% of skipjack tuna (n = 10) and 12.5% of dolphinfish (n = 8).
  3. Yellowfin tuna (n = 10) did not contain any MPD, probably owing to the high proportion of empty stomachs (60%).
  4. For skipjack tuna, the frequency of occurrence of MPD ingestion was significantly higher for the smaller-sized specimens caught with pole-and-line (40%), compared with the larger-sized specimens caught with longlines (0%).
  5. For dolphinfish, the frequency of occurrence of MPD ingestion was similar for the similar-sized specimens caught with pole-and-line and with longlines.
  6. The ingested MPD items were micro–meso plastics, between 1 and 25 mm. While most ingested items were fragments, albacore also ingested line and skipjack also ingested sheets.
  7. The predatory fishes ingested light MPD items that float in sea water, but there were species-specific differences in their polymer composition: albacore contained more polypropylene and polyethylene, and skipjack contained more elastomers, characterized by a high percentage of ester plasticizers.
  8. Altogether, these results suggest that albacore and skipjack tunas ingest plastic of different types and polymers. Yet more research is needed to understand how differences in vertical distribution, foraging ecology and diet influence the MPD sampled by these predatory fish species.
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3.
Intravenous alfaxalone, administered at a dose of 5 mg/kg in the jugular vein, was evaluated in 20 leopard geckos (Eublepharis macularius) to ascertain its ability to provide anesthesia. The induction time, time to loss of mandibular tone, interval of deep anesthesia, and full recovery time were 27.5 ± 30.7 seconds (10 to 56 seconds), 1.3 ± 1.4 minutes (11 seconds to 4 minutes), 12.5 ± 2.2 minutes (11.11 to 15.39 minutes), and 18.8 ± 12.1 minutes (10.4 to 52.31 minutes), respectively. A significant reduction in heart rate (74 ± 12.9 beats/minute) was recorded between 2 and 24 minutes after alfaxalone administration. A significant decrease in respiratory rate (26.8 ± 10.1 breaths/minute) was recorded 2 minutes after alfaxalone administration, and respiratory rate remained lower than the basal rate (31.4 ± 3.1 breaths/minute) for 24 minutes but without statistical significance. The intravenous administration of alfaxalone in leopard geckos achieved a rapid onset of anesthesia and a suitable recovery time. Based on this investigation, an afaxalone dose of 5 mg/kg intravenously proved to be suitable for sedation before tracheal intubation. Moreover, the administration route via the jugular vein, was acceptable in leopard geckos; a species in which other venipuncture sites can be challenging or inaccessible.  相似文献   
4.
An understanding of variation in fruit quality in relation to tree age can help understand the issue of poor fruit quality in young orchards; however, limited information is available on the citrus fruit. In this study, the endogenous nutritional status in rind, rag, and leaves; pectin status in rind and rag; and anatomical fruit growth parameter in rind tissues were studied in ‘Kinnow’ mandarins fruit during their development on trees from three age (6-, 18-, and 35-year-old) groups. In older (35-year-old) trees, rind, rag, and leaf nitrogen (N), phosphorus (P), and potassium (K) concentrations were superior. In fruit from all tree age groups, total pectin and protopectin reduced; however water-soluble pectin (WSP) improved. In rind tissues harvested from young (6-year-old) trees, cell density was more while cell size was less. In all tree age groups, cell density in rind tissues correlated negatively with rind WSP.  相似文献   
5.
Among the treatments of exogenous foliar spray application of sulphates of cobalt (Co) and cadmium (Cd) at 0, 250, 500, 1000, and 1500 ppm, and nickel (Ni) at 0, 100, 200, and 400 ppm prior to flower bud differentiation in the first week of October, cobalt sulphate (1000 ppm) or cadmium sulphate (1500 ppm) significantly (P=0.05) reduced floral malformation of mango (Mangifera indica L) cv. Langra by 65 to 71% and increased the fruit yield by 35 to 37%. The physical characteristics of the fruit were not affected significantly at the lower concentrations but higher concentrations of Co and Cd caused reduction. Total and non‐reducing sugars in the fruit were adversely affected by the higher rates of Co and Ni applied, but exhibited no effect on total soluble solids percentage (TSS%) or reducing sugars. The foliar spray application of the sulphates of Co, Ni, and Cd increased their respective concentrations in the leaf tissue without any phytotoxic symptoms. Most of the desirable effects were achieved with the 1000 ppm cobalt sulphate treatment applied in the first week of October prior to flower bud differentiation.  相似文献   
6.
The concentrations of iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and cobalt (Co) in malformed and healthy panicles of mango (Mangifera indica L.), leaves and shoots bearing them were analyzed at: (i) fully swollen bud, (ii) bud inception, (iii) fully grown panicles prior to full bloom, and (iv) full bloom over three consecutive years. The concentrations of Fe, Zn, Cu, Mn, and Co varied in malformed and healthy organs at various developmental stages. Malformed panicles exhibited lower levels of Fe, Zn, Cu, and higher Mn than healthy ones. The leaves on the shoots bearing malformed panicles showed higher levels of Fe, Mn, Cu, and higher Zn than the leaves on the shoots bearing healthy panicles. The shoots bearing malformed panicles revealed higher levels of Fe, Zn, Mn, and Cu than shoots bearing malformed panicles. The levels of Co in healthy and malformed organs did not differ much. The findings of the present study, therefore, seem to point that floral malformation in mango is not caused by the deficiency of these micronutrients.  相似文献   
7.
Aqueous solutions (0, 0.01, 0.1, 1 mM) of PAs (putrescine, spermine, spermidine) containing a surfactant ‘Tween 20’ were sprayed onto panicles of mango (Mangifera indica L. cv. Kensington Pride) at final fruit set (FFS) stage (when all flowers abscised but remain attached to the panicle) during 1999–2001 to investigate their effects on fruit retention, yield, size, and fruit quality. The optimum time of PA application for improving final fruit retention and fruit yield was determined by spraying different concentrations (0, 0.01, 0.1, 1 mM) of spermine (SPM) containing a surfactant ‘Tween 20’ at four phenological stages including flower bud differentiation (FBD), 5–8 cm long grown panicles (GP), full bloom (FB) and at initial fruit set (IFS) stage (when 2/3rd of the flowers were abscised but attached to the panicle) during 2000. Exogenous application of PAs at FFS stage did not significantly increase fruit retention. However, compared to control (0.79 and 2.3% fruit retention), PAs treatments resulted in comparatively higher mean fruit retention (1.53 and 2.92%) during 1999–2000 and 2000–2001, respectively. Among three PAs tested, SPM was more effective in increasing mean final fruit retention. Fruit size was not significantly affected by any PA treatment. Among the four application times, SPM (0.01 mM) spray at FB stage resulted in significantly (P ≤ 0.05) greater fruit retention (4.99%) compared with control (2.1%). However, fruit yield was comparatively higher with SPM (0.01 mM) application at IFS stage or 5–8 cm GP stage compared to the control. Overall FB application was found as the optimum time of application. Application of PAs at FFS stage retarded fruit skin colour development compared to the control. Sugars and total soluble solids (TSS) were generally reduced in PA-treated fruit. Fruit acidity was increased (16.7%) with SPM, whereas it was 11% with PUT treatment as compared to the control. Total carotenoids in pulp were generally improved (49%) with PA treatments, compared to the control. Ascorbic acid concentrations were significantly reduced with spermidine (SPD) (24%) and PUT (20%) treatments, whereas higher concentrations of SPM (1 mM) tended to increase it (12.7%) compared to the control. In conclusion, application of SPM (0.01 mM) at FB stage resulted in the highest fruit retention, whereas SPM (0.01) spray at GP or IFS stage resulted in higher fruit yield. PUT application at FFS stage significantly improved fruit quality by increasing total carotenoid, while reducing acid content of ripe fruit.  相似文献   
8.
To compare the effect of methods (foliar and soil) and rate of application of zinc sulphate on zinc and phosphorus uptake, tree size, yield and fruit quality of mango (Mangifera indica L.) cv. Dusheri, zinc sulphate was applied as a foliar spray application (0.25, 0.50, 1.0%) and soil (0.5, 1.0, 2.0 kg tree‐1) treatments during the second week of October (during flower bud differentiation period). All the zinc sulphate treatments of soil and foliar spray were effective in increasing the leaf zinc concentrations above recommended adequate level of (>20 mg kg‐1) whereas control trees maintained low leaf zinc concentrations (13.8 to 13.3 mg kg‐1). The uptake of foliar‐applied zinc was more rapid than that of soil applied zinc. All the treatments of zinc sulphate except the foliar spray treatment of zinc sulphate (0.25%) significantly increased zinc concentrations in the fruit pulp as compared with those in the control trees. The percent increase in the stem girth of trees was highest with the soil application of zinc sulphate (0.5 kg tree1) followed by foliar application of zinc sulphate (1.0%) as compared with all other treatments. The percent increase in the tree canopy volume was highest with the foliar application of zinc sulphate (1.0%) followed by soil application of zinc sulphate (1.0 kg tree1) as compared with control and all other treatments. There was no significant (P<0.05) increase in yield, fruit size and weight, pulp or stone weight with any treatment of zinc sulphate. Total soluble solid (TSS) in the fruit was significantly higher (18.6%) with the treatment of soil application of zinc sulphate (0.5 kg tree1) as compared with all other treatments of zinc sulphate and the control. Acid and sugar content of the fruit was not significantly affected by the foliar or soil application of zinc sulphate.  相似文献   
9.
Einkorn (Triticum monococcum L., subsp. monococcum), emmer (Triticum dicoccum Schuebl [Schrank], subsp. dicoccum) and spring bread wheat (Triticum aestivum L.) may be rich in lipophilic antioxidants (tocols and carotenoids), and therefore potential food sources with good nutritional properties. The aim of the present study was to determine the contents of major lipophilic antioxidants beneficial for human health in wheat varieties and landraces for breeding and production. In field experiments over two years, fifteen einkorn, emmer and spring wheat varieties were analysed for the contents of tocols and carotenoids in grain. A high carotenoid content (lutein, zeaxanthin, β-carotene) was typical for the selected einkorn genotypes. Among the analysed wheat species, the highest content was of β-tocotrienol, especially in the einkorn accessions. α-Tocotrienol was abundant in einkorn and emmer wheat species. Higher contents of α- and β-tocopherols were characteristic of spring and emmer wheats. δ-Tocotrienol has been detected for the first time in einkorn and some emmer accessions, although in low concentrations. Significant effects of genotype on the contents of carotenoids and tocols were found with einkorn differing from emmer and spring wheats. The year of cultivation had less effect on the contents of carotenoids and tocols. Selected accessions of einkorn with high contents of carotenoids and tocotrienols as well as spring and emmer wheats with higher contents of tocopherols are good sources of antioxidants with potential health promoting benefits for the production of nutritionally enhanced foods.  相似文献   
10.
Serum amyloid A proteins (SAA) are very sensitive acute phase proteins, displaying multiple isoforms in plasma and different body fluids. They are currently under investigation as biomarkers of diseases. The aim of the present study was to compare the concentration and isoform expression of SAA in serum and milk of cows with bacteriologically negative milk (control group) and naturally occurring Staphylococcus aureus (S. aureus) subclinical mastitis (subclinical mastitis group). Somatic cell count (SCC) and bacteriological analyses were performed to establish the control and subclinical mastitis group. SAA concentration was evaluated using a commercial ELISA kit, while expression of different isoforms (serum A-SAA and milk M-SAA3 isoforms) was visualized by denaturing isoelectrical focusing and immunoblotting. The SAA concentrations in sera and milk of cows in the subclinical mastitis group were three and 100 times higher than in those from the control group of cows, respectively. Cows in the subclinical mastitis group had more acidic SAA isoforms in serum with the most prominent one at pI 5.5. This isoform was not detected in sera from the control group. Milk samples in the subclinical mastitis group contained abundant highly alkaline M-SAA3 isoforms and most of the serum isoforms, except for that at pI 5.5. In the subclinical mastitis group SAA isoforms with equivalent pI as serum isoforms accounted for 20% of the total SAA concentration in milk. There were significant differences in the concentrations and isoform patterns of SAA in serum and milk between the control and subclinical mastitis groups of cows. Also, we demonstrated that serum SAA isoforms were not transferred to milk proportion to their plasma content.  相似文献   
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