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41.
Throughfall (TF), stemflow (SF), soil solution below the organic layer (SSorg) and at 50 cm depth (SS50), and output with stream water (SW) were measured and analyzed for four years in a moderately polluted forest catchment in southern Poland. The input of water with stemflow was ca. 6% of input with TF. However, due to higher concentrations of most ions in SF, the input of most elements with SF was from 8% to 9%. Sulphate (SO4 2–), chloride (Cl) and magnesium (Mg2+) were the only ions steadily increasing in concentrations in water percolating through the soil profile. Nitrogen reached the forest floor mainly as ammonium (NH4 +). In the soil organic layer the NH4 + concentration decreased, while concentrations of nitrate (NO3 ) and hydrogen (H+) increased, probably due to nitrification. For NO3 , sodium (Na+) and calcium (Ca2+), the highest concentrations were found in SSorg and SW. This indicates both efficient cycling in the biotic pool of the ecosystem and intensive weathering processes in the mineral soil below the plant rooting zone. The latter was especially pronounced for Mg and Ca. Concentrations of zinc (Zn), lead (Pb) and cadmium (Cd) were the highest in SSorg and SS50. As this was accompanied by a low pH and constant input of H+, NH4 + and heavy metal ions to the catchment area, it may pose a serious threat to forest health.  相似文献   
42.
Poppy seed oil (Oleum Papaveris Seminis) is used for culinary and pharmaceutical purposes, as well as for making soaps, paints, and varnishes. Astonishingly, hardly anything was yet known about the volatile compounds of this promising comestible. Likewise, there are no current published data about the triglyceride (TAG) composition of poppy seed oils available. In this investigation solid-phase microextraction (SPME) with DVB/Carboxen/PDMS Stable-Flex fiber was applied to the study of volatile compounds of several seed oil samples from Papaver somniferum L. (Papaveraceae). 1-Pentanol (3.3-4.9%), 1-hexanal (10.9-30.9%), 1-hexanol (5.3-33.7%), 2-pentylfuran (7.2-10.0%), and caproic acid (2.9-11.5%) could be identified as the main volatile compounds in all examined poppy seed oil samples. Furthermore, the TAG composition of these oils was analyzed by MALDI-ReTOF- and ESI-IT-MS/MS. The predominant TAG components were found to be composed of linoleic, oleic, and palmitic acid, comprising approximately 70% of the oils. TAG patterns of the different poppy varieties were found to be very homogeneous, showing also no significant differences in terms of the applied pressing method of the plant seeds.  相似文献   
43.
Iceland sheep are found to be relatively early maturing and the level of reproductive efficiency in the flock is raised by breeding from ewe lambs. Ram lambs are normally used for mating. Ewe prolificacy is progressively being increased by genetic selection for a higher lambing rate in conjunction with improvements in feeding. Lamb mortality is kept at a relatively low level by close supervision at lambing and disease control.  相似文献   
44.
Infection of Trichinella spp. is widespread among wildlife in Slovakia and the red fox (Vulpes vulpes) is the main reservoir of Trichinella britovi. Trichinella spiralis has been rarely documented in sylvatic and domestic animals of this country. During routine examination of domestic pigs at the slaughter, Trichinella larvae were detected by artificial digestion in a domestic pig of a large-scale breeding farm in Eastern Slovakia. The parasite has been identified by molecular (PCR) and biochemical (allozymes) analyses and by the morphology of the nurse cell as the non-encapsulated species Trichinella pseudospiralis infecting both mammals and birds. The epidemiological investigation carried out at the farm level revealed the presence of the same parasite species in other three pigs of 192 examined (2.1%), in 3 of 14 (21.4%) examined synanthropic rats (Rattus norvegicus) and in a domestic cat. The farm was characterized by inadequate sanitary conditions, insufficient nutrition, cannibalism and the presence of rat population. A different profile has been observed at the phosphoglucomutase locus in T. pseudospiralis isolates from Slovakia in comparison with the T. pseudospiralis reference isolate from the Palearctic region. This is the first documented focus of T. pseudospiralis from Central Europe. The detection in domestic pigs of a non-encapsulated parasite infecting both mammals and birds stresses the need to avoid the use of trichinelloscopy to detect this infection at the slaughterhouse.  相似文献   
45.
Collisions in the asteroid belt frequently lead to catastrophic breakups, where more than half of the target's mass is ejected into space. Several dozen large asteroids have been disrupted by impacts over the past several billion years. These impact events have produced groups of fragments with similar orbits called asteroid families. Here we report the discovery of a very young asteroid family around the object 1270 Datura. Our work takes advantage of a method for identification of recent breakups in the asteroid belt using catalogs of osculating (i.e., instantaneous) asteroid orbits. The very young families show up in these catalogs as clusters in a five-dimensional space of osculating orbital elements.  相似文献   
46.
 为研究金钱槭果实中的化学成分,利用各种波谱技术从金钱槭果实乙醇提取物中共分离得到4个三萜类成分(1-4)和一个甾体化合物(5),利用波谱技术及化学方法将它们分别鉴定为高根二醇 (1)、28-羟基-12-齐墩果烯-3-酮 (2)、高根二醇3-O-棕榈酸酯 (3)、羽扇豆烯酮 (4)和豆甾-4-烯-3-酮 (5),所有化合物均首次从该植物中发现。  相似文献   
47.
48.
本试验旨在研究低蛋白质饲粮中添加尿素对肉兔消化代谢的影响。采用单因子随机区组试验设计,选择 90只 50日龄体重相近的健康新西兰兔,随机分为 3组,1个对照组和 2个试验组,每组 15个重复,每个重复 2只。对照组饲喂粗蛋白质含量为 11.11%的基础饲粮,2个试验组分别饲喂在基础饲粮中以糊化淀粉缓释尿素的方式添加 1%、2%和 3%尿素的试验饲粮。预试期为 10d,正试期为 30d。正试期的第 13~18天收集试验兔排出的全部粪便和尿液。结果表明:与对照组相比,1%尿素组试验兔的有机物表观消化率、总能表观消化率及利用率、沉积氮、氮利用率和消化氮利用率显著或极显著升高(P<0.05或 P<0.01),而 2%尿素组试验兔的消化能、代谢能、沉积氮、氮利用率和消化氮利用率显著或极显著降低(P<0.05或 P<0.01)。对照组试验兔盲肠内容物脲酶活性和微生物蛋白浓度显著或极显著低于其余 2组(P<0.05或 P<0.01),而 2%尿素组试验兔盲肠内容物氨氮和尿素氮浓度显著或极显著高于其余 2组(P<0.05或 P<0.01)。由此得出,低蛋白质饲粮中添加 1%尿素可改善肉兔有机物、总能和氮的利用效率,提高盲肠内容物脲酶活性和微生物蛋白浓度;添加 2%尿素则会降低肉兔氮的利用效率,提高盲肠内容物脲酶活性及微生物蛋白、氨氮和尿素氮浓度。  相似文献   
49.
The Aerococcus viridans isolates from bovine mastitis in Slovakia were isolated and characterized by classical microbiological and biochemical, and molecular techniques including IGS-PCR and rep-PCR, ARDRA and 16S rDNA gene sequencing. The substantial variability of antibiotic resistance patterns was observed. The majority of strains were resistant to beta-lactam antibiotics, the resistance to tetracycline was observed in 3 tested strains, resistance to lincomycin was found in 4 strains and practically all tested strains were sensitive to neomycin and ciprofloxacin. While variable at a phenotypic level, no significant genetic variability among A. viridans isolates was detected by molecular DNA based methods. The data obtained suggest that a few A. viridans strains spread among cow's population in Slovak farms.  相似文献   
50.
Vavilovia (Vavilovia Fed.) is one of the five genera in tribe Fabeae and consists of only one species, ‘beautiful’ vavilovia (Vavilovia formosa (Stev.) Fed.). The main centre of distribution is the Central and Eastern Caucasus, with a disjunct distribution among high alpine areas in the region, extending as far as West Turkey, Lebanon and Iran. In Armenia, in situ studies on Vavilovia started in the late 1930s. In July and August 2009, three expeditions were conducted to two locations: two to the Ughtasar Mountain and one to the Geghama Mountains. The first expedition to Ughtasar resulted in fresh plant collections and soil analysis for one of the sites. The expedition to Geghama established the existence of Vavilovia in the region of Lake Aknalitch. The second expedition to Ughtasar provided immature fruits and seeds. Collected plant material was transplanted into the Flora and Vegetation of Armenia plot of the Yerevan Botanic Garden established in 1940. Today, along with other plants the plot contains more than 200 species of wild relatives of cultural plants from 130 genera, including indiginous species of tribe Fabeae such as Vavilovia. The transplanted plants will continue to be monitored to see if the plants go on to successfully flower and set seed or whether further sites, possibly at higher altitudes might need to be tested to meet the long term conservation requirements of this iconic legume. These co-ordinated efforts provide a good example of an ex situ conservation strategy for Vavilovia formosa, which, if successful will improve access and utility for the whole legume research community.  相似文献   
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