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181.
The presence of stolons is taxonomically significant in the genus Liriope Linn.
However, probably due to a lapse of attention, F. T. Wang and T. Tang failed to re-
cognize Ophiopogon muscari Decne., type of Liriope muscari (Decne.) Bailey, a non-
stoloniferous taxon, and erroneously referred it as a synonym to the stoloniferous L.
spicata Lour. At the same time, however, they described another non-stoloniferous
species-L. platyphylla Wang et Tang (L. muscari Bailey) as new.
What, then, is the difference between L. platyphylla Wang et Tang and L. mus-
cari (Decne.) Bailey? A comparison of the type photo of Ophiopogon muscari Decne.
with specimens of L. platyphylla Wang et Tang shows that the two forms are much alike,
but the latter has longer scapes usually overtopping the foliage, as well as longer spikes
and broader leaves. L. H. Bailey must had combined the two forms into one species.
Furthermore. there are another two non-stoloniferous forms, both having scapes shorter
than their foliage, but differing from L. muscari (Decne.) Bailey in their much nar-
rower leaves. One of them has very short leaves and looks like L. minor Makino.
Finally, what are the correlations among the above four forms? By using methods
of quantitative analysis, such as pictorialized scatter diagram and histogram, on her-
barium material, it has been found that the L. muscari complex can be separated into
two parts: 1) muscari (M), and 2) platyphylla (P). But since these two parts dis-
play a continuous variation pattern as a whole, it seems advisable to treat both as varie-
ties of the same species, i. e., L. muscari (Decne.) Bailey var. muscari, and L. muscari
var. communis (Maxim.) Hsu et L. C. Li. (Ophiopogon spicatus Ker-Cawl. var. com-
munis Maxim.) As to the other two narrow-leaved forms, they can hardly be regarded
as sufficient for two distinct infraspecific units, for they are found to be inseparablefrom each other as well as from muscari. 相似文献
182.
According to Wang and Xie, their recently published genus Trirostellum is
distinguished from its allied genera by a number of characteristics: (1) the stamens
with their filaments coherent into a central column; (2) the female flowers possessing
rudimentary stamens; (3) the ovary 3-celled, with one ovule in each cell; (4) the fruits
dehiscent, 3-rostrated at the apex; (5) the fruits possessing persistent perianth; (6)
the seeds tuberculate and winged. However, upon a careful comparison of Trirostell-
um yixingensis Z.P. Wang et Q. Z. Xie, the type species of Trirostellum with Gyno-
stemma pentaphyllum (Thunb.) Mak., the type species of Gynostemma Bl. and some
other species of Gynostemma as well,we have found that the representatives of the
above two genera are identical in most of the important diagnostic characteristics ex-
cept that the fruits of the former genus are dehiscent with three long beaks at the
apex, while the fruits of the latter genus are indehiscent with very short beaks.
Besides, results obtained from chromosome counting haove shown that the somatic
chromosome number of Trirostellum yixingensis is 2n=22, while that of Gynostemma
pentaphyllum is 2n=28.Yet these morphological and chromosomal differences seem
not sufficient for generic demarcation. We, therefore, suggest that Trirostellum bereduced to a sectional or subgeneric rank of Gynostemma Bl. 相似文献
183.
A report of chromosome numbers for eight species endemic to China is
made in the paper, including first counts for 4 genera and 4 species and first karyoty-
pic analyses of two species.
Sinojohnstonia chekiangensis (Migo) W. T. Wang (Boraginaceae) 2n=24*;
Coptis chinenis Franch (Ranunculaceae) 2n=18**;
Dichocarpum dalzielii (Drumm. et Hutch.) W. T. Wang et Hsiao (Ranunculaceae)
2n=24*;
Eomecon chionantha Hance (Papaveraceae) 2n=18;
Camptotheca acuminata Dcne. (Nyssaceae) 2n=44;
Calycanthus chinensis Cheng et S. Y. Chang (Calycanthaceae) 2n=22**;
Eucommia ulmoides Oliv. (Eucommiaceae) n=17;
Pinellia pedatisecta Schott (Araceae) 2n=26;
The previous reports of chromosome numbers of the same groups are compared with
our own (See Table 1). The vouchers for the present study are preserved in the Herba-
rium of Futan University. 相似文献
184.
David S. Crystal Chuansheng Chen rew J. Fuligni Harold W. Stevenson Chen-Chin Hsu Huei-Jen Ko Seiro Kitamura Susumu Kimura 《Child development》1994,65(3):738-753
American, 1,633 Chinese, and 1,247 Japanese eleventh-grade students, 5 indices of maladjustment included measures of stress, depressed mood, academic anxiety, aggression, and somatic complaints. Asian students reported higher levels of parental expectation and lower levels of parental satisfaction concerning academic achievement than their American peers. Nevertheless, Japanese students reported less stress, depressed mood, aggression, academic anxiety, and fewer somatic complaints than did American students. Chinese students reported less stress, academic anxiety, and aggressive feelings than their American counterparts, but did report higher frequencies of depressed mood and somatic complaints. High academic achievement as assessed by a test of mathematics was generally not associated with psychological maladjustment. The only exception was in the United States, where high achievers indicated more frequent feelings of stress than did low achievers. 相似文献
185.
Pei-Ling Hsu Wen-Gin Yang 《International Journal of Science and Mathematics Education》2007,5(4):639-659
Systemic functional linguistics (SFL) was the foundation for this study that explored the effect of science text and image
integration on grade 9 students’ reading comprehension. Two texts in Chinese on the moon phase with different print and image
integration were compared—a traditional textbook (TT) used in Taiwanese junior high schools and a systemic functional linguistics
text (SFLT) created by the authors for this study. These two texts contained similar concepts but had major differences in
several features: technicality, representational structure, degree of modality, and interaction between print and image. A
control-experimental design with pretest, posttest, and semi-structured interviews was used. In total, 132 junior high school
students were randomly assigned to two groups: one group (n=69) read the TT and the other group (n=63) read the SFLT. Sixteen students with both high and low performances in the posttest were purposely selected as the subjects
of the follow-up interviews. Major findings were: (a) students who read the SFLT demonstrated significantly better achievement
than those who read the TT, and (b) students who read the TT generated more misconceptions about the moon phase and had greater
difficulty in making sense of the images than the students who read the SFLT. Accordingly, SFL may serve as a useful theoretical
framework and tool in the design of textbooks and may have a practical application in the science classroom. 相似文献
186.
Teacher views about constructivist instruction and personal epistemology: a national study in Taiwan
This study investigated the views about constructivist instruction and personal epistemology of the secondary earth science teachers in Taiwan. Participants were assessed through a paper‐and‐pencil survey and a Learning environment preference questionnaire (LEP) designed to explore personal epistemology. On a five‐point Likert scale, teachers, on average, showed a neutral agreement on constructivist instruction. The content analysis suggested that teachers held alternative views about the nature of the constructivist instruction. LEP scores were found to be statistically associated with gender, education, current teaching level and years of teaching; the score distribution indicated that most teachers had not developed a constructivist‐compatible epistemology. By one‐way ANOVA, it was suggested that views about the constructivist instruction were aligned with personal epistemology. 相似文献
187.
山茱萸属应予重新确认 总被引:1,自引:0,他引:1
The genus Macrocarpium has been accepted only by a few scholars since
its separation from Cornus L. by T. Nakai in 1909. Bentham, Hooker, Hutchinson and
the others consider that the ovary of Macrocarpium is 2-celled and the genus should be
placed back into Cornus. We have discovered that are generally I-celled. In addition,
Macrocarpium is different from Cornus in basic chromosome number (X), flowering
physiological character, inflorescence type and involucral scale. Thus the genus Ma-crocarpium (Spach) Nakai should be reaffirmed. 相似文献
188.
南京两种半夏群体水平变异式样的比较 总被引:1,自引:0,他引:1
南京东郊灵谷寺山坡有一种半夏属Pinellia植物,它外观上与半夏P.ternata相似,但无珠芽;在形态上则更近似鹞落坪半夏P.yaoluopingensis,但缺少子块茎。本文以两个半夏群体和一个鹞落坪半夏(暂名)群体为对象,从生境的调查、形态性状的测量、花粉粒电镜扫描和显微观察以及染色体的计数人手,对两种半夏的变异式样进行比较。结果表明鹞落坪半夏群体与半夏群体的区别在于:(1)营养器官绝无珠芽,佛焰苞檐部边缘决非紫红色,雄花序长度比半夏短,雌花序和附属器长度均比半夏长;(2)花粉粒比半夏小,虽都呈圆球形,但小刺状纹饰较稀疏;(3)染色体2n=26,与半夏群体2n=72不同;(4)半夏具有一定杂草特性,在不同程度人为干扰的环境中能很好地生长和开花。鹞落坪半夏则常见于落叶阔叶林下层未受人为干扰的环境中。 相似文献
189.
Building on previous self-concept and current physical self-concept (PSC) theories, this paper presents empirical results demonstrating the triad relationship among physical exercise, PSC, and quality of life (QoL) in older adults. Specifically, the results show how PSC mediates the relationship between physical exercise and health-related quality of life (HQoL). A total of 152 older adults participated in this study, completing the Leisure Time Exercise Questionnaire, Physical Self-Concept Scale for Older Adults, and 12-Item Short-Form Survey. Hierarchical multiple regression analyses were conducted to test the mediating effects. Older adults’ physical exercise, PSC, and QoL were all correlated. The components of older adults’ PSC (strength, flexibility, and independent functioning) fully mediated the relationship between physical exercise and the physical as well as mental aspects of HQoL. This study thus suggests that PSC plays an important explanatory role in the effect of older adults’ physical exercise on their QoL. Health-care professionals may use various strategies to enhance older adults’ self-perception during physical exercise in order to promote their global well-being. 相似文献
190.
This paper proposes four resource (subcarriers-and-bits) allocation methods for OFDMA-based multiuser MIMO system. We employ adaptive modulation according to the channel state information (CSI) of each user to meet the symbol error rate (SER) requirement. The first scheme is based on transmit spatial diversity (TSD), in which the vector channel with the highest gain between the base station and specific antenna at remote terminal is chosen for transmission. The second scheme assigns subcarrier to the best user and employs spatial multiplexing on the MIMO system to further enhance the throughput. The space-division multiple-access (SDMA) scheme assigns single subcarrier simultaneously to the remote terminals with pairwise “nearly orthogonal” spatial signatures. In the fourth scheme, we propose to design the transmit beamformers based on the zero-forcing (ZF) criterion such that the multi-user interference (MUI) is completely removed. Moreover, spatial multiplexing technique is jointly exploited to achieve throughput multiplication. Numerical results demonstrate that all the proposed algorithms are simple and reliable and the fourth scheme is the best since all users are allowed to share single subcarrier. 相似文献