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1.
The " A" - " Not A" method is a rating method with two categories. It is often treated as a discrimination method. Unlike forced choice procedures, the Thurstonian model for this method involves a choice criterion. In statistical tests, it is treated as a comparison of two proportions. In this paper, the power for hypothesis tests involving the monadic and replicated monadic " A" - " Not A" method is discussed. The power functions and the sample sizes needed for 80% power are given based on Thurstone's δ. Designs with equal and unequal allocations for A and A (Not A) samples are considered. The power of the method is also compared with that of four forced choice methods under the assumption that the perceptual variance is identical among methods. The comparison shows that, in general, the power for the five methods ranks from high to low: the 3-AFC, 2-AFC, " A" - " Not A", triangular and duo-trio. The comparison also shows that, based on the same number of panelists and/or the same sample size for the A and A samples for the methods, if the panelists are not too discrepant and the choice criterion in the " A" - " Not A" method is not too strict or too lax, the power of the " A" - " Not A" method is very close to that of the 2-AFC method.  相似文献   

2.
中国古本草书艾蒿类植物的初步考订   总被引:5,自引:1,他引:4  
林有润 《植物研究》1991,11(1):1-24
本文对中国古本草书记载的艾蒿类植物,如白蒿、艾、白艾、艾蒿、野艾蒿、苹、籟蒿、水蒿、萎蒿、柳叶蒿、(艹闾)蒿、艾叶、家艾、蕲艾、牛尾蒿、草蒿、青蒿、黄花蒿、香蒿、臭蒿、狃蒿、邪蒿、茵陈蒿)蓬高、野同蒿、紫香蒿、牡蒿、齐头蒿、水辣菜、奄闾子、庵(艹闾)、刘寄奴及金寄奴等作了初步考订,同时对一些名为"艾"或"蒿"但非菊科蒿属植物亦作一初步的考订。  相似文献   

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4.
Scarab beetles of the subgenus Nobius Mulsant et Rey, genus Aphodius Illiger, distributed in Russia and neighboring countries are reviewed. A key to the species and notes on their biology are given. The three new synonymies are established: A. serotinus (Panz.),1799 = A. x-signum Reitter, 1892, syn. n.; A. gresseri Sem. 1898 = A. korgaldzhensis Nikolajev, 1987, syn. n.; A. chaldaeus Petr., 1971 = A. moreleti Baraud, 1980, syn. n. Lectotypes of A. inclusus Reitt., 1892 and A. gresseri are designated.  相似文献   

5.
One new species,Astragalus tiehmii, and two new varieties,A. convallarius var.margaretae andA. oophorus var.lavinii, are described from Nevada; the relationships of each are discussed and the first is illustrated. Two new combinations,A. eurylobus (Barneby) Barneby andA. serenoi var.shockleyi (M. E. Jones) Barneby are proposed and defended. A new species,A. bryogenes, is described from high Andean Peru (Junín).  相似文献   

6.
报道了国产黄耆属(Astragalus)6种植物的染色体数目和核型。结果表明,这6种黄耆属植物均为二倍体,其核型公式分别为:甘青黄耆(A.tangutlcus),2n=16=6m 8sm 2t,“3A”核型;悬垂黄耆(A.dependens),2n=16=10m 6sm,“2A”核型;四川黄耆(A.sutchuenensis),2n=16=8m 8sm,“2A”核型;萨雷古拉黄耆(A.pavlovlanus),2n=16=12m 4sm,“1A”核型;喜石黄耆(A.petraeus),2n=16=14m 2sm,“1A”核型;拟糙叶黄耆(A.pseudoscaberrimus),2n=16=14m 2sm,“1A”核型。这6种黄耆属植物的染色体数目和核型均为首次报道。  相似文献   

7.
Summary The eukaryotic and prokaryotic databases are scanned for potential nearest-neighbor doublet preferences at the 5 and 3 flanks of some oligomers. Here we focus on oligomers containing alternating nucleotides, i.e., UV, UVUV, and UUVV where UV. Strong, consistent trends are observed in eukaryotic sequences. A/T alternation oligomers are preferentially flanked by A/T. G/C flanks are disfavored. G/C alternation oligomers are preferentially flanked by G/C. A/T flanks are disfavored. These trends are consistent with those observed previously for homooligomer tracts (Nussinov et al. 1989a,b). G/C tracts are preferentially flanked by G/C. A/T nearest neighbors are disfavored. The reverse holds for A/T tracts. Additional patterns are described here as well. The possible origin of these DNA composition and sequence trends is discussed. These trends are suggested to stem from protein-DNA interaction constraints.  相似文献   

8.
采用大田种植和盆栽方法,分别研究了不同的立地类型(平地、阳坡、阴坡和坡地)和土壤类型(砂土、壤土和黏土)对产自河南省方城县的"裕丹参"(Salvia miltiorrhiza Bunge)生长和有效成分含量的影响效应.结果表明:在不同立地条件下,"裕丹参"的各项生长和根系产量指标以及根系中丹参酮ⅡA和丹酚酸B含量均有明显差异.随种植时间的延长,平地、阳坡和坡地种植的"裕丹参"单株地上部干质量均逐渐降低,而阴坡种植的单株地上部干质量先升高后逐渐降低;但在不同立地类型下,单株根系干质量和丹酚酸B含量均随种植时间的延长逐渐升高,而丹参酮ⅡA含量则先降低后升高.采收期,平地种植的"裕丹参"的单株地上部干质量、单株根系干质量和鲜质量以及根系鲜产量均最高,平地和坡地种植的"裕丹参"根直径较大,阳坡种植的"裕丹参"根长最长,阳坡和坡地种植的"裕丹参"单株根数、根系中丹参酮ⅡA和丹酚酸B含量也较高,而阴坡种植的"裕丹参"的各项生长和根系产量指标以及丹参酮ⅡA和丹酚酸B含量均最低.在不同类型土壤中,"裕丹参"的根系性状和根系中丹参酮ⅡA和丹酚酸B含量总体上差异显著,其中,用砂土种植的"裕丹参"的根直径、根长、单株根系鲜质量和干质量以及根系中丹参酮ⅡA和丹酚酸B含量均最高,但单株根数最少;用黏土种植的"裕丹参"根系生长总体最差,但单株根数最多;用壤土种植的"裕丹参"根系中丹参酮ⅡA和丹酚酸B含量则最低.综合研究结果显示:"裕丹参"适宜种植于砂土的坡地或阳坡.  相似文献   

9.
Group a mutants of Clostridium perfringens are deficient in theta toxin but release a dialyzable substance ("substance A"), which restores theta toxin activity to group b mutants, into a culture supernatant; group b mutants are defective in "substance A" release. "Substance A" activity appeared in the exponentially growing phase of group a mutants and disappeared in the stationary phase. "Substance A" activity was most stable at pH 5.0 and 0 C and even increased threefold in the first 5 hr, but gradually decreased during the following 15 hr. It was quickly inactivated at neutral and higher pHs at 0 C.  相似文献   

10.
In addition to the earlier detected C81(A) rare variants A1, A2 (now A3) and B1 (now B2), six new rare variants (C81 A2 new, A4, A5, A6, M1 and B1new) are described within the polymorphism of the eighth component of human complement (- chain subunit). Except for A3, all rare C81 A variants are only detected by isoelectric focusing, and not by SDS polyacrylamide gel electrophoresis (PAGE), in the - subunit. In one individual out of approximately 700 individuals studied, a reversed position of the common allele (B vs A) was observed by SDS PAGE and the isofocusing technique. The segregation of A1, A3 and A4 could be followed in putative father/child combinations.  相似文献   

11.
Phylogenetic analyses of nuclear rDNA spacers (ITS and ETS) from Azorella and five closely related genera confirm earlier plastid results indicating that Azorella, Huanaca, Mulinum, and Schizeilema are all polyphyletic, and that the monotypic genus Laretia is nested within one of the six subclades of Azorella. Only Stilbocarpa is monophyletic, but that genus is embedded within a larger clade that includes representatives of three other genera (Azorella, Huanaca, and Schizeilema). Both nuclear and plastid datasets identify the same 10 clades, but the placement of these clades remains unstable. A new classification is presented in which these six genera are reduced to a single genus (Azorella) comprising 58 species arranged in 10 sections, one of which is newly described here (Azorella sect. Ranunculus), and one lectotypified (Azorella sect. Glabratae). A total of 13 new combinations are made (A. albovaginata, A. allanii, A. boelckei, A. burkartii, A. colensoi, A. echegarayi, A. echinus, A. hallei, A. lyallii, A. polaris, A. prolifera, A. robusta, A. ulicina), along with three replacement names (A. atacamensis, A. ruizii, A. schizeilema). For each of the 58 accepted species, a full synonymy is provided along with geographic ranges (and nomenclatural notes, where useful).  相似文献   

12.
13.
14.
Lipid droplets (LDs) are independent organelles that are composed of a lipid ester core and a surface phospholipid monolayer. Recent studies have revealed many new proteins, functions, and phenomena associated with LDs. In addition, a number of diseases related to LDs are beginning to be understood at the molecular level. It is now clear that LDs are not an inert store of excess lipids but are dynamically engaged in various cellular functions, some of which are not directly related to lipid metabolism. Compared to conventional membrane organelles, there are still many uncertainties concerning the molecular architecture of LDs and how each function is placed in a structural context. Recent findings and remaining questions are discussed.Lipid droplets (LDs) were recognized as a mere deposit of lipid esters for many years. Recently, LDs have been redefined as authentic organelles that are actively engaged in multiple functions, and these have been reviewed in many recent articles (Murphy 2001; Martin et al. 2006; Ducharme et al. 2008; Fujimoto et al. 2008; Goodman 2008; Olofsson et al. 2008; Thiele et al. 2008; Murphy et al. 2009; Walther et al. 2009; Beller et al. 2010). The name, lipid droplets, implies the opposite: a static and inert nature. Alternative names have been proposed, but lipid droplet is now a generally agreed nomenclature (Martin et al. 2006).LDs are intimately related to many aspects of lipid metabolism. The lipid storage function of LDs is most conspicuous in white adipocytes, which have a gigantic unilocular LD. The regulation of the process of lipid storage and utilization has been the focus of many studies because of the prevalence of obesity, type II diabetes, and metabolic syndrome in the modern world.Besides the canonical lipid-related function, various new functions have been ascribed to LDs more recently, including some that do not appear to be directly related to lipid metabolism. However, both the canonical and noncanonical functions of LDs, are rooted in the unique architecture of LDs. In contrast to other organelles that have aqueous content within a phospholipid bilayer membrane, the basic structure of LDs is thought to be a mass of lipid esters covered by a phospholipid monolayer (Murphy et al. 1999; Tauchi-Sato et al. 2002). In this article, we first review what is known about LD structure and then discuss various functions. We review this information by considering the extent to which the functions can be understood based on the current structural paradigm.  相似文献   

15.
16.
Variation in lateral awn length and pulvini development is described for A. pansa and A. gypsophila. The two species are distinguished by lateral awn development. Within each species, forms are based on pulvini development. Three new forms are described (A. pansa f. contracta; A. gypsophila f. gypsophiloides and f. diffusa), A. dissita is reduced to a form of A. pansa, and A. tehuacanensis is considered synonymous with A. pansa f. dissita. Keys, illustrations, and maps are provided.  相似文献   

17.
18.
Aspergillus spp. are emerging causative agents of non-dermatophyte mould onychomycosis (NDMO). New Aspergillus spp. have recently been described to cause nail infections. The following criteria are required to diagnose onychomycosis due to Aspergillus spp.: (1) positive direct microscopy and (2) repeated culture or molecular detection of Aspergillus spp., provided no dermatophyte was isolated. A review of 42 epidemiological studies showed that onychomycosis due to Aspergillus spp. varies between < 1 and 35% of all cases of onychomycosis in the general population and higher among diabetic populations accounting for up to 71% and the elderly; it is very uncommon among children and adolescence. Aspergillus spp. constitutes 7.7–100% of the proportion of NDMO. The toenails are involved 25 times more frequently than fingernails. A. flavus, A. terreus and A. niger are the most common aetiologic species; other rare and emerging species described include A. tubingensis, A. sydowii, A. alliaceus, A. candidus, A. versicolor, A. unguis, A. persii, A. sclerotiorum, A. uvarum, A. melleus, A. tamarii and A. nomius. The clinical presentation of onychomycosis due to Aspergillus spp. is non-specific but commonly distal–lateral pattern of onychomycosis. A negative culture with a positive KOH may point to a NDM including Aspergillus spp., as the causative agent of onychomycosis. Treatment consists of systemic therapy with terbinafine or itraconazole.  相似文献   

19.
John T. Mickel 《Brittonia》1981,33(3):413-429
This distinctive subgenus, limited to calcareous rocks of the Caribbean basin, is discussed in terms of its taxonomy and relationships. Two new species,A. alternifolia andA. pumilio are described, and two new combinations,A. mexicana var.makrinii andA. coriacea f. nipeensis are made. Drawings of all taxa are provided.  相似文献   

20.
广西大苗山“打鸟坳”趋光性鸟类调查   总被引:6,自引:1,他引:5  
2000年9月、2001年5月和10月2、002年5月和10月、2003年10月、2005年9月,通过实地调查和访问当地群众的方法,对广西大苗山“打鸟坳”的趋光性鸟类进行了调查,在大苗山发现了规模较大的“打鸟坳”共5个,并记录趋光性鸟类58种,隶属于10目14科。其中留鸟16种,夏候鸟15种,冬候鸟17种,旅鸟10种。趋光性鸟类主要以鹭科(Ardeidae)、三趾鹑科(Turnicidae)、秧鸡科(Rallidae)等涉禽为主。鹭科鸟类数量较多的有白鹭(Egretta garzetta)和池鹭(Ardeola bacchus);三趾鹑科数量最多的为黄脚三趾鹑(Turnix tanki);秧鸡科以白胸苦恶鸟(Amaurornis phoenicurus)最多。文中还对“打鸟坳”的形成以及部分留鸟被捕获的现象进行了讨论,并对大苗山“打鸟坳”鸟类的保护提出了建议。  相似文献   

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