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101.
Thakur Manisha Luharch Rakshandha Sharma Vishal Sharma Dharam Paul 《Genetic Resources and Crop Evolution》2022,69(2):567-575
Genetic Resources and Crop Evolution - Santa Rosa and Frontier are the major Japanese plum (Prunus salicina Lindl.) cultivars grown throughout the world. The present investigation was performed to... 相似文献
102.
Three different commercially available structural plastic media were evaluated in triplicate in moving bed biofilters under low salinity (11–12 ppt) warm water culture conditions and two different feed loading rates. The culture system consisted of nine separate modules that include a double drain fish culture tank paired to a moving bed biofilter. The biofilters were filled with 0.11 m3 of one of three different types of floating plastic structured media. The three types of media evaluated were K1 kaldnes media, MB3 media, and AMB media. Volumetric total ammonia nitrogen (TAN) removal rates (g TAN removed/m3 media-day), TAN removal efficiency, and biofilm kinetic constants, Ki (h−1) were determined for the three media types at two different daily feed load rates of 3.5 and 8.2 kg feed/m3 media. The feed provided was a 4.8 mm slow sinking marine grower diet pellet (45% protein, 17% fat). Average (±standard deviation, SD) volumetric TAN removal rates (VTR) at the lower feed load for the three media types were 92.2 ± 26.3, 86.1 ± 27.5, and 82.5 ± 25.9 for the MB3, AMB, and K1 kaldnes media, respectively. At the higher feed load the average VTR for the three media types was 186.4 ± 53.7, 172.9 ± 47.8, and 139.9 ± 38.9 for the MB3, AMB, and K1 kaldnes media, respectively. Influent TAN concentrations varied by the feed load rate and ranged from 0.55 to 0.93 mg/L and 0.83 to 1.87 mg/L for the low and higher feed loads, respectively. The percent TAN removal rates for the MB3 media was the highest of the three media types at both the low and high feed load rates averaging 12.3% and 14.4%, respectively. The MB3 media was selected for use in the moving bed biofilters because of the greater VTR and removal efficiency results for use in the 0.11 m3 moving bed biofilters of the hatchery recirculating aquaculture system. 相似文献
103.
104.
The Paleocene-Eocene Thermal Maximum (PETM, approximately 55 million years ago) was an interval of global warming and ocean acidification attributed to rapid release and oxidation of buried carbon. We show that the onset of the PETM coincided with a prominent increase in the origination and extinction of calcareous phytoplankton. Yet major perturbation of the surface-water saturation state across the PETM was not detrimental to the survival of most calcareous nannoplankton taxa and did not impart a calcification or ecological bias to the pattern of evolutionary turnover. Instead, the rate of environmental change appears to have driven turnover, preferentially affecting rare taxa living close to their viable limits. 相似文献
105.
He ZD Qiao CF Han QB Cheng CL Xu HX Jiang RW But PP Shaw PC 《Journal of agricultural and food chemistry》2005,53(7):2424-2428
Cassia bark or cortex cinnamomi, the dried stem bark of Cinnamomum cassia Presl. (Lauraceae), is a popular natural spice and a commonly used herb in traditional Chinese medicine. However, adulterants are frequently found in the market. In this study, 44 samples of Cassia bark including bark from seven related Cinnamomum species were collected from fields and market. Four characteristic components, cinnamaldehyde, cinnamic acid, cinnamyl alcohol, and coumarin were determined by RP-HPLC, and a fingerprint comprised of five markers was established. These results showed that cassia barks contained high contents of cinnamaldehyde (13.01-56.93 mg/g). The highest content of cinnamaldehyde (up to 93.83 mg/g) was found in debarked cortex, which is traditionally regarded as having the best quality in local herb shops. In contrast, the adulterants from the other Cinnamomum species, C. wilsonii Camble, C. japonicum Sieb., C. mairei Levl. and C. burmanii (Nees) Blume, contained low contents of cinnamaldehyde (<2.00 mg/g). The content of cinnamaldehyde in C. loureirii Nees was comparable to that in C. cassia. It is suggested that five characteristic peaks by HPLC are suitable for distinguishing genuine cassia bark from the adulterants and could be applied in the quality control of this commodity. 相似文献
106.
Lipid separation from cheddar cheese whey allows a better valorization of protein fractions. In this study, bipolar membrane electroacidification (BMEA) was used to obtain precipitates with a high level of lipids. Whey samples with normal and low (by way of electrodialysis) mineral salt levels have been treated by a BMEA process and centrifuged. The composition of flocs and precipitation yields were determined. The BMEA process increased lipid precipitation rates by almost 50% in comparison with a centrifugation step only whereas a demineralization step prior to electroacidification had a limited effect on the precipitation level. Precipitates obtained were mainly composed of lipids (probably phospholipids) but also contained proteins. BMEA of cheddar cheese whey would allow the production of a lipid-enriched fraction and of a protein-enriched whey. 相似文献
107.
Yelena V. Lyubun Paul V. Kosterin Elena A. Zakharova Alexander A. Shcherbakov Evgenii E. Fedorov 《Journal of Soils and Sediments》2002,2(3):143-147
Background, Aim and Scope Environmental pollution caused by arsenic (As) is a major ecological problem. There has been intense worldwide effort to find
As-hyperaccumulating plants that can be used in phytoremediation—the green-plant-assisted removal of chemical pollutants from
soils. For phytoremediation, it is natural to prefer cultivated rather than wild plants, because their agriculture is well
known. This study was conducted to evaluate the tolerance of common sunflower(Helianthus annuus L.) and sugar sorghum(Sorghum saccharatum Pers.) for soil-As contents of 10–100 mg As kg-1 soil, with sodium arsenite as a model contaminant.
Methods Plants were grown in a growth chamber for 30 days. Microfield experiments were conducted on experimental plots. To study the
phytoremediation effect of the auxins indole-3-acetic acid (IAA) and 2,4-dichlorophenoxyacetic acid (2,4-D), we treated 1-
and 3-day-old plant seedlings with water solutions of the auxins (concentrations 10-5, 10-7, and 10-9 g l-1). The soil and plant-biomass samples were analyzed for total As by using the color reaction of ammonium molybdate with As.
Results and Discussion Phytotoxicity studies showed that 100 mg As kg-1 soil poisoned sunflower and sorghum growth by 50%. There was a linear correlation between soil-As content and As accumulation
in the plants. Laboratory experiments showed that the soil-As content was reduced two- to threefold after sunflower had been
grown with 10–100 mg As kg-1 soil for 30 days. Treatment of sunflower and sorghum seedlings with IAA and 2,4-D at a concentration of 10-5 g l-1 in microfield experiments enhanced the phytoremediation two- to fivefold as compared with untreated control plants. The best
results were obtained with 3-day-old seedlings.
Conclusion, Recommendation and Outlook (a) Sunflower and sorghum are good candidates to remediate As-polluted soils. (b) Phytoremediation can be improved with IAA or 2,4-D. (c) Mixed cropping of sorghum and sunflower may be another way of improving phytoremediation. 相似文献
108.
The dispersal ecology of most stream fishes is poorly characterised, complicating conservation efforts for these species. We used microsatellite DNA marker data to characterise dispersal patterns and effective population size (Ne) for a population of Roanoke logperch Percina rex, an endangered darter (Percidae). Juveniles and candidate parents were sampled for 2 years at sites throughout the Roanoke River watershed. Dispersal was inferred via genetic assignment tests (ATs), pedigree reconstruction (PR) and estimation of lifetime dispersal distance under a genetic isolation‐by‐distance model. Estimates of Ne varied from 105 to 1218 individuals, depending on the estimation method. Based on PR, polygamy was frequent in parents of both sexes, with individuals spawning with an average of 2.4 mates. The sample contained 61 half‐sibling pairs, but only one parent–offspring pair and no full‐sib pairs, which limited our ability to discriminate natal dispersal of juveniles from breeding dispersal of their parents between spawning events. Nonetheless, all methods indicated extensive dispersal. The AT indicated unrestricted dispersal among sites ≤15 km apart, while siblings inferred by the PR were captured an average of 14 km and up to 55 km apart. Model‐based estimates of median lifetime dispersal distance (6–24 km, depending on assumptions) bracketed AT and PR estimates, indicating that widely dispersed individuals do, on average, contribute to gene flow. Extensive dispersal of P. rex suggests that darters and other small benthic stream fishes may be unexpectedly mobile. Monitoring and management activities for such populations should encompass entire watersheds to fully capture population dynamics. 相似文献
109.
Evidence for ozone formation in human atherosclerotic arteries 总被引:1,自引:0,他引:1
Wentworth P Nieva J Takeuchi C Galve R Wentworth AD Dilley RB DeLaria GA Saven A Babior BM Janda KD Eschenmoser A Lerner RA 《Science (New York, N.Y.)》2003,302(5647):1053-1056
Here, we report evidence for the production of ozone in human disease. Signature products unique to cholesterol ozonolysis are present within atherosclerotic tissue at the time of carotid endarterectomy, suggesting that ozone production occurred during lesion development. Furthermore, advanced atherosclerotic plaques generate ozone when the leukocytes within the diseased arteries are activated in vitro. The steroids produced by cholesterol ozonolysis cause effects that are thought to be critical to the pathogenesis of atherosclerosis, including cytotoxicity, lipid-loading in macrophages, and deformation of the apolipoprotein B-100 secondary structure. We propose the trivial designation "atheronals" for this previously unrecognized class of steroids. 相似文献
110.
Changelian PS Flanagan ME Ball DJ Kent CR Magnuson KS Martin WH Rizzuti BJ Sawyer PS Perry BD Brissette WH McCurdy SP Kudlacz EM Conklyn MJ Elliott EA Koslov ER Fisher MB Strelevitz TJ Yoon K Whipple DA Sun J Munchhof MJ Doty JL Casavant JM Blumenkopf TA Hines M Brown MF Lillie BM Subramanyam C Shang-Poa C Milici AJ Beckius GE Moyer JD Su C Woodworth TG Gaweco AS Beals CR Littman BH Fisher DA Smith JF Zagouras P Magna HA Saltarelli MJ Johnson KS Nelms LF Des Etages SG Hayes LS Kawabata TT 《Science (New York, N.Y.)》2003,302(5646):875-878
Because of its requirement for signaling by multiple cytokines, Janus kinase 3 (JAK3) is an excellent target for clinical immunosuppression. We report the development of a specific, orally active inhibitor of JAK3, CP-690,550, that significantly prolonged survival in a murine model of heart transplantation and in cynomolgus monkeys receiving kidney transplants. CP-690,550 treatment was not associated with hypertension, hyperlipidemia, or lymphoproliferative disease. On the basis of these preclinical results, we believe JAK3 blockade by CP-690,550 has potential for therapeutically desirable immunosuppression in human organ transplantation and in other clinical settings. 相似文献