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211.
The Anderson-Kannemann test is a rank test for treatment effects in a randomized block design with K treatments and N blocks. In this paper, an algorithm for computing the exact distribution of the Anderson-Kannemann test statistic under the null hypothesis is deduced. Then, the exact distribution is compared with the asymptotic χ2-distribution, and it is shown that the exact distribution is approximated fairly well by the asymptotic distribution. Tables of the exact distribution are given for K = 3, N = 3(1)15; K = 4, N = 3(1)11; K = 5, N = 3(1)7; and K = 6, N = 3(1)5.  相似文献   
212.
Protein, amino acids and ammonium were the main forms of soluble soil nitrogen in the soil solution of a subtropical heathland (wallum). After fire, soil ammonium and nitrate increased 90- and 60-fold, respectively. Despite this increase in nitrate availability after fire, wallum species exhibited uniformly low nitrate reductase activities and low leaf and xylem nitrate. During waterlogging soil amino acids increased, particularly γ-aminobutyric acid (GABA) which accounted for over 50% of amino nitrogen. Non-mycorrhizal wallum species were significantly (P < 0.05) 15N-enriched (0.3–4.3‰) compared to species with mycorrhizal associations (ericoid-type, ecto-, va-mycorrhizal) which were strongly depleted in 15N (-6.3 to -1.8‰). Lignotubers and roots had δ15N signatures similar to that of the leaves of respective species. The exceptions were fine roots of ecto-, ecto/va-, and ericoid type mycorrhizal species which were enriched in 15N (0.1–2.4‰). The 515N signatures of δ15Ntotal soil N and δ15Nsoil NH4+ were in the range 3.7–4.5‰, whereas δ15Nsoil NO3? was significantly (P < 0.05) more enriched in 15N (9.2–9.8‰). It is proposed that there is discrimination against 15N during transfer of nitrogen from fungal to plant partner. Roots of selected species incorporated nitrogen sources in the order of preference: ammonium > glycine > nitrate. The exception were proteoid roots of Hakea (Proteaceae) which incorporated equal amounts of glycine and ammonium.  相似文献   
213.
Hyaluronic acid transduces a very gentle pressure into an electrical potential. Such pressure, depending on its direction, changes the optical rotary dispersion properties of the salt, either increasing the rotation in the direction already shown by the unpressured salt or changing and increasing the rotation in the opposite direction. These findings have implications for understanding the funtion of the cochlear and vestibular fluids, renal function, and the approximation to frictionless motion of normal joints.  相似文献   
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This study is aimed at evaluating the likelihood that kin-biased distribution will be expressed or detected in a range of brown trout ( Salmo trutta ) populations as a function of family size. Microsatellite analysis indicated that fewer full- and half-siblings were found in populations with larger effective population sizes, while more full- and half-siblings were found in populations with lower effective population size. It is suggested that kin-biased distribution and hence kin-biased behaviours are not likely to be expressed equally frequently in all populations since the number of close relatives will vary among populations and, hence, the opportunity for relatives to interact differs among populations. These findings can, at least partly, explain the discrepancy among previous studies of kin-biased distribution in wild salmonids under natural conditions. Effective population size could, hence, be used to predict the salmonid populations in which kin-biased distribution are more likely to occur and be detected.  相似文献   
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Even though significant breakthroughs with over 18% power conversion efficiencies (PCEs) in polymer:non‐fullerene acceptor (NFA) bulk heterojunction organic solar cells (OSCs) have been achieved, not many studies have focused on acquiring a comprehensive understanding of the underlying mechanisms governing these systems. This is because it can be challenging to delineate device photophysics in polymer:NFA blends comprehensively, and even more complicated to trace the origins of the differences in device photophysics to the subtle differences in energetics and morphology. Here, a systematic study of a series of polymer:NFA blends is conducted to unify and correlate the cumulative effects of i) voltage losses, ii) charge generation efficiencies, iii) non‐geminate recombination and extraction dynamics, and iv) nuanced morphological differences with device performances. Most importantly, a deconvolution of the major loss processes in polymer:NFA blends and their connections to the complex BHJ morphology and energetics are established. An extension to advanced morphological techniques, such as solid‐state NMR (for atomic level insights on the local ordering and donor:acceptor π? π interactions) and resonant soft X‐ray scattering (for donor and acceptor interfacial area and domain spacings), provide detailed insights on how efficient charge generation, transport, and extraction processes can outweigh increased voltage losses to yield high PCEs.  相似文献   
219.
Open‐circuit voltages of lead‐halide perovskite solar cells are improving rapidly and are approaching the thermodynamic limit. Since many different perovskite compositions with different bandgap energies are actively being investigated, it is not straightforward to compare the open‐circuit voltages between these devices as long as a consistent method of referencing is missing. For the purpose of comparing open‐circuit voltages and identifying outstanding values, it is imperative to use a unique, generally accepted way of calculating the thermodynamic limit, which is currently not the case. Here a meta‐analysis of methods to determine the bandgap and a radiative limit for open‐circuit voltage is presented. The differences between the methods are analyzed and an easily applicable approach based on the solar cell quantum efficiency as a general reference is proposed.  相似文献   
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