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排序方式: 共有184条查询结果,搜索用时 15 毫秒
1.
Efficacy of 1?mM humic (HA) and salicylic (SC) acids on SC 260 and SC 705 corn seedlings to alleviate drought stress via polyethylene glycol was studied via hydroponics at Shiraz University, Iran in a factorial, randomized design, with four replicates each. Under stress, SC 260 had higher electrolyte leakage compared to SC 705, and exogenous application of HA combined with SA decreased SC 705 electrolyte leakage. As a general trend, photosynthetic pigment content, relative water content, root and shoot length, mean number and diameter of central and peripheral root metaxylem, and K+ accumulation were higher in SC 705 treated with HA and SA compared to SC 260. Application of HA with SA could be an effective and low cost approach to ensure seedling establishment and plant growth in fields affected by soil drought in the early season, especially for the SC 705 corn hybrid in semi-arid regions. 相似文献
2.
Damian Gianina Elena Micle Valer Sur Ioana Monica 《Journal of Soils and Sediments》2019,19(7):2869-2881
Journal of Soils and Sediments - The aim of the research was to determine the potential of dissolved humic substances extracted from leonardite to mobilize Cu and Pb from multi-metal contaminated... 相似文献
3.
Development of efficient and eco-friendly sorbents used for selective oil removal after oil spill disasters is one of the main topics in environmental science. By using various cellulosic materials coated with graphene flakes, using simple, one-step dip-coating method, it was possible to manufacture environmentally friendly, selective oil sorbents. The cellulosic materials of different yarn size and distribution such as cotton roving, gauze, fabric, and cellulosic wipe and Whatman filter paper were chosen. The scanning electron microscopy showed that simple dip-coating of any cellulosic materials into graphene dispersion creates a uniformly distributed nanomaterial coating. The wetting tests confirmed that the coating endowed cellulosic materials with hydrophobic properties, regardless of their initial yarn distribution and purity. Moreover, the water repellent samples were simultaneously highly sorptive towards oils and organic solvents. Sorption tests performed for a representative group of organic solvents and oils have shown that depending on cellulosic material the oil sorption capacity varied from 4 g/g to 33 g/g for cotton fabric and roving, respectively. Moreover, the absorption selectivity of chloroform versus water exceeded 90 % for each sample and reached over 99 % for the graphene coated cotton roving and gauze. Finally, the recyclability tests have shown that graphene coated materials are less fragile for reuse than naturally hydrophobic sorbents. 相似文献
4.
C. W. Ryan K. Bishop D. D. Blaney S. J. Britton F. Cantone C. Egan M. G. Elrod C. W. Frye A. M. Maxted G. Perkins 《Zoonoses and public health》2018,65(4):420-424
Melioidosis in humans presents variably as fulminant sepsis, pneumonia, skin infection and solid organ abscesses. It is caused by Burkholderia pseudomallei, which in the United States is classified as a select agent, with “potential to pose a severe threat to both human and animal health, to plant health or to animal and plant products” (Federal Select Agent Program, http://www.selectagents.gov/ , accessed 22 September 2016). Burkholderia pseudomallei is found in soil and surface water in the tropics, especially South‐East Asia and northern Australia, where melioidosis is endemic. Human cases are rare in the United States and are usually associated with travel to endemic areas. Burkholderia pseudomallei can also infect animals. We describe a multijurisdictional public health response to a case of subclinical urinary B. pseudomallei infection in a dog that had been adopted into upstate New York from a shelter in Thailand. Investigation disclosed three human contacts with single, low‐risk exposures to the dog's urine at his residence, and 16 human contacts with possible exposure to his urine or culture isolates at a veterinary hospital. Contacts were offered various combinations of symptom/fever monitoring, baseline and repeat B. pseudomallei serologic testing, and antibiotic post‐exposure prophylaxis, depending on the nature of their exposure and their personal medical histories. The dog's owner accepted recommendations from public health authorities and veterinary clinicians for humane euthanasia. A number of animal rescue organizations actively facilitate adoptions into the United States of shelter dogs from South‐East Asia. This may result in importation of B. pseudomallei into almost any community, with implications for human and animal health. 相似文献
5.
- Amphidromy is the most prevalent type of diadromous migration. Despite this, the conservation and management of amphidromous species is exceptionally challenging because this life history type, with larval development in a pelagic habitat (usually marine) and adult development in fresh water, is poorly resolved.
- The chronological properties of otoliths, together with a spatial and temporal analysis of post‐larval migration traits and adult reproductive traits, were used to reconstruct the life history of a widespread, yet declining amphidromous galaxiid, Galaxias maculatus, and to explore relationships between marine and freshwater life phases.
- A wide range of post‐larval migration traits were observed over the peak migratory period. Post‐larvae were smaller and younger at inward migration late in the migration season (November) and were derived from winter spawning events. Earlier migrants (September) were larger, older and derived from autumn spawning events.
- Age estimates confirmed that G. maculatus is largely an annual species, but back‐calculated hatch dates showed that spawning times are more extensive than previously known.
- Growth reconstructions revealed that winter‐hatched larvae were faster growing during marine and freshwater life and attained sexual maturity at a younger age than autumn‐hatched fish. However, no differences in body size or reproductive investment were detected between autumn‐ and winter‐hatched larvae.
- The first 50 days of marine growth were inter‐dependent, indicating that early larval growth may be the critical link to understanding intra‐ and inter‐annual recruitment variations of inward migrating post‐larvae. Furthermore, growth after 60 days of larval life propagated through to adult freshwater development, highlighting linkages between late marine and adult freshwater life.
- This study highlights the value of studying the marine and freshwater life phases of amphidromous species in tandem. This interconnected understanding must ultimately be achieved for the conservation and management of species with this poorly understood life history type.
6.
7.
Monika Staniaszek-Kik Jan Żarnowiec Damian Chmura 《European Journal of Forest Research》2016,135(6):1145-1157
8.
Gustavo R. Rodríguez Javier H. Pereira da Costa Damian D. Tomat Guillermo R. Pratta Roxana Zorzoli Liliana A. Picardi 《Scientia Horticulturae》2011
The tomato fruit quality results of biochemical and physiological changes that occur during the ripening process. Although, the pericarp total protein profiles are less polymorphic than DNA-based markers the polymorphism in those could be directly associated with fruit quality traits. The aim of this work was to identify associations between polymorphic polypeptides from fruit pericarp at two ripening stages and fruit quality traits evaluated in two segregating populations of tomato. A cross between a normal ripening cultivar of Solanum lycopersicum (C, Caimanta) and a genotype carrying the nor (non ripening) gene (N) as well as a cross between Caimanta and a cherry type tomato of S. lycopersicum var. cerasiforme (Ce) showed genetic variance for several fruit quality traits such as fruit weight, shape, solids soluble content, acidity, color and fruit shelf life. The quantitative variations observed at phenotypic level had correspondence with the polymorphism detected in the protein profiles. Indeed, the polymophic polypeptides associated with quality fruit traits and fruit shelf life would be useful to assist tomato breeding programs as protein molecular markers. 相似文献
9.
The impact of thermal pollution of leachate from a post-coal mine heap on three macrophyte species: Phragmites australis, Typha latifolia, and Scirpus sylvaticus was examined over the entire vegetation season. Hydrological measurements showed that the temperature of the leachate was ca 50?°C at the site of leachate inflow and decreased to ca 15?°C at the end of discharge canal. The annual temperature and conductivity of leachate from the two control sites, a polluted water stream in the vicinity of the waste tip and an unpolluted stream, differ significantly. However, only the temperature explained the differences in plant traits. In April, and in some cases in May, plants in the leachate were significantly higher than in those on the control sites in terms of biomass and plant height. Thermal pollution caused a phenological shift in all species and also caused Scirpus plants to die out more quickly. Temperature also affected the proportion flowering vs. vegetative individuals, e.g., none of Scirpus plants started to bloom. 相似文献
10.
Graeme J. Eamens Jocelyn R. Gonsalves Cheryl Jenkins Damian Collins Graham Bailey 《Veterinary parasitology》2013,191(3-4):209-217
Between September 2010 and November 2011, 350 EDTA blood samples were received from 73 Australian cattle herds, as cases suspected to be infected with Theileria orientalis. Beef cattle were predominantly affected, with Angus and Angus-crossbred cattle representing 48% of smear positive samples examined. DNA extracts were tested in conventional polymerase chain reaction (PCR) assays for genes encoding the p32, Ikeda, Chitose and Buffeli major piroplasm surface proteins (MPSP). PCR findings were compared with results of clinical pathology examinations of stained blood smears for parasitaemia and packed cell volume (PCV). PCR testing was much more sensitive than clinical pathology examinations in detecting T. orientalis infections, and concurrent testing of neat and diluted extracts gave significantly more PCR positive results than testing of neat extract alone. Significant associations and correlations were shown between PCR results of p32 and Ikeda assays with PCV levels indicative of anaemia, and with the level of parasitaemia estimated by smears. A high proportion of samples had concurrent Ikeda and Chitose infection, and significantly more clinical cases of theileriosis were associated with the Ikeda MPSP type as the sole infection, compared with sole infection with types Chitose or Buffeli. The findings indicate Ikeda type organisms were significantly associated with clinical parameters of theileriosis in cattle herds in eastern Australia, and that this type is most likely to be responsible for outbreaks of theileriosis experienced in affected Australian herds. In New South Wales, 11 of 14 regulatory districts yielded Ikeda positive samples, with five (Mid-Coast, Cumberland, Central North, Hume and Lachlan) containing 234/307 (76%) of the Ikeda positive samples. 相似文献