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51.
Inhabitants of some Transylvanian farms in Romania have a valuable archaic knowledge of medicinal plants because of their isolation and the insufficiency of official medical treatment. In this work we present ethnobotanical data about the use of medicinal plant taxa for various respiratory diseases in the villages L?véte and Nagybacon. Altogether 34 plant taxa were documented in L?véte and 26 species in Nagybacon with 15 concordant data of the villages. This information plays an important role in the documentation of the disappearing indigenous medical information of the villages. 相似文献
52.
Lajos Soukup 《Discrete Mathematics》2011,311(15):1585
The use of elementary submodels is a simple but powerful method to prove theorems, or to simplify proofs in infinite combinatorics. First we introduce all the necessary concepts of logic, then we prove classical theorems using elementary submodels. We also present a new proof of Nash-Williams’s theorem on cycle decomposition of graphs, and finally we improve a decomposition theorem of Laviolette concerning bond-faithful decompositions of graphs. 相似文献
53.
In this paper we determine all the bijective linear maps on the space of bounded observables which preserve a fixed moment or the variance. Nonlinear versions of the corresponding results are also presented. 相似文献
54.
We characterize linear rank-k nonincreasing, rank-k preserving, and corank-k preserving maps on B(H), the algebra of all bounded linear operators on the Hilbert space H. This unifies and extends finite-dimensional results and results on linear rank-1 non-increasing and rank-1 preserving maps in the infinite-dimensional case. We conclude with an application to *-semigroup isomorphisms of operator ideals. 相似文献
55.
56.
Edward G. Coffman Jr. Jnos Csirik Lajos Rnyai Ambrus Zsbn 《Discrete Applied Mathematics》2008,156(14):2810-2816
The average-case analysis of algorithms usually assumes independent, identical distributions for the inputs. In [C. Kenyon, Best-fit bin-packing with random order, in: Proc. of the Seventh Annual ACM-SIAM Symposium on Discrete Algorithms, SIAM, 1996, pp. 359–364] Kenyon introduced the random-order ratio, a new average-case performance metric for bin packing heuristics, and gave upper and lower bounds for it for the Best Fit heuristics. We introduce an alternative definition of the random-order ratio and show that the two definitions give the same result for Next Fit. We also show that the random-order ratio of Next Fit equals to its asymptotic worst-case, i.e., it is 2. 相似文献
57.
In 1952, F. Pollaczek gave a method for finding the distribution of the maximal partial sum of mutually independent and identically distributed random variables. In this paper, Pollaczek's results are extended, and the extended results are applied in theory of queues for finding the distribution of the waiting time for single server queues. 相似文献
58.
Zusammenfassung Die 3,3-Dimethylnaphthidin-Wasserstoffperoxid-Redoxreaktion wird von Jodid sehr stark katalysiert. Damit kann man bei Anwesenheit von Ameisensäure Jodid selbst in einer Grenzkonzentration von 0,002g/ml nachweisen bzw bestimmen. Dazu eignet sich die Simultankomparationsmethode. Im Konzentrationsbereich von 0,1 bis 0,01g J–/5 ml beträgt der relative Fehler 3%. Ag+, Hg2+ oder Bi3+ dürfen nicht anwesend sein; andere störende Ionen können mit ÄDTA bzw. Weinsäure maskiert werden.
Catalytic detection and determination of traces of iodine by means of the 3,3-dimethylnaphthidine-hydragen peroxide reaction
Summary The 3,3-dimethylnaphthidine-hydrogen peroxide redox reaction is strongly catalysed by iodide. Therefore, if formic acid is present, iodide itself may be detected or determined in a limiting concentration of 0.002g/ml. The simultaneous comparation method is appropriate here. In the concentration region from 0.1 to 0.01g I–/5 ml, the relative error is 3%. Ag+, Hg2+ or Bi3+ may not be present. Other interfering ions can be masked with EDTA or tartaric acid.相似文献
59.
Summary In the proof of the main result of the original paper there is an error. Instead of repairing that proof to get just the original result, at the critical spot we improve the proof and obtain a much better result. In particular, we approximate the product-limit and empirical cumulative hazard processes by suitable copies of the corresponding limiting Gaussian processes with rates of approximation that on appropriate fixed half lines reduce to the rates of Komlós, Major and Tusnády for the uncensored empirical process. 相似文献
60.