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71.
72.
 The fern genus Diplaziopsis C. Chr. of Index Filicum has long been considered as a monotypic one, with the sole species, D. javanica (B1.) C. Chr. from tropical Asia.  In 1906, H. Christ described a second species, Allantodia cavaleriana Christ (=D. cavale- riana C. Chr.) from Kweichow, West China, but this was since not fully recognized by fern students in general, being often considered as a variety of the first species.  This is certainly a mistake, as is shown by ample herbarium specimens today.  In the recent work on the genus, the writer has found among the herbarium material two additional new species from China, thus bringing the genus up to four species in Asia, mainly from China, where, as it is, the genus has its center of development from the long past.      Phylogenetically, Diplaziopsis C. Chr. represents one of the offshoots from the great stock of diplazioid ferns, of which the genus Diplazium Sw. constitutes the main body of the group and from which our genus differs chiefly in its leaves of a thin texture with reticulated venation, but not so much in its type of indusium as it has generally been emphasized by most botanists in the past, for, as it is, the type of indusium in Di- plaziopsis also prevails in many species of Diplazium, for which C. B. Clarke (Trans. Linn. Soc. ser. 2, Bot. I:495, 1880) created, but really superfluously, a subgenus Pseudal- lantodia, about which the writer will dwell in another paper in the near future.  Suffice it to say here that the indusium in Diplaziopsis as revealed by the species treated here is, indeed, typical of diplazioid ferns, only often, as it happens, with  its  adaxial  edge pressed so tight under the expanding sorus that it is unable to open freely along its upper free edge and, as a result, its thin vaulted back bursts open from the pressure of the ex- panding sorus underneath.      As a result of the present study, following four species of the genus have been re- cognized.      Diplaziopsis javanica (B1.) C. Chr. Ind. Fil. (1905) 227.      Wide spread in tropical Asia, northwardly to Bakbo and the southern part of Yun- nan, China.      D. cavaleriana (Christ) C. Chr. Ind. Fil. Suppl. I (1913) 25.      Ranges from West China through northern part of Fukien of East China to Japan.      D. intermedia Ching, sp. nov.      Endemic in West China:  Mt. Omei, Szechuan, and Kweichow.      D. hainanensis Ching, sp. nov.      In conclusion, it may be pointed out that with the modern plant taxonomy pursued in a more efficient manner than in the past, and especially by the introduction of the cytotaxonomic methods, the so-called “monotypic genera”, as conceived by the orthodox systematists, will continue to prove, to a great extent, to be lack of  enough  scientific ground.  The fact that the “monotypic genus” of Diplaziopsis C. Chr. is now found to be a genus of four well-defined species is once again an instance to illustrate the pointat issue.  相似文献   
73.
The present paper aims at clarifying the identity of Asplenium varians Wall. and its related species for the forthcoming Flora of China vol. 4. Wide-spread in the northern, north-western and south-western parts of China and adjacent regions and growing in exposed rock crevices is the group of ferns in question, which has hi- therto been taxonomically confused in the botanical literature.  Many distinct and related species were previously identified as Aspl. varians, a most wide-spread fern with very variable fronds which may vary from 10 to 30 cm in height and from simply pinnate to fully bipinnate in the degree of pinnation in a single clump under different habitats.  相似文献   
74.
This paper presents findings from a three-year, qualitative study of teachers enrolled in a Masters of Teacher Leadership program. Researchers sought to understand the ways teachers’ beliefs about and understandings of teacher leadership were affected by their participation in a formal teacher leadership program, as well as the kinds of actions they took up as a result of this participation. Data indicate three significant ways participants’ work as teacher leaders was developed and enhanced, including: (a) identifying and amplifying their professional voice, (b) deepening and extending their voice as they plan, and (c) reframing their work/shift responsibility through constructing widening circles of influence and impact. Authors identify implications of their research for growing teacher leaders, school improvement and change, changing school culture, enhancing student engagement, and building new structures.  相似文献   
75.
The purpose of this study was to examine which emergent literacy skills contribute to preschool children's emergent writing (name-writing, letter-writing, and spelling) skills. Emergent reading and writing tasks were administered to 296 preschool children aged 4-5 years. Print knowledge and letter-writing skills made positive contributions to name writing; whereas alphabet knowledge, print knowledge, and name writing made positive contributions to letter writing. Both name-writing and letter-writing skills made significant contributions to the prediction of spelling after controlling for age, parental education, print knowledge, phonological awareness, and letter-name and letter-sound knowledge; however, only letter-writing abilities made a significant unique contribution to the prediction of spelling when both letter-writing and name-writing skills were considered together. Name writing reflects knowledge of some letters rather than a broader knowledge of letters that may be needed to support early spelling. Children's letter-writing skills may be a better indicator of children's emergent literacy and developing spelling skills than are their name-writing skills at the end of the preschool year. Spelling is a developmentally complex skill beginning in preschool and includes letter writing and blending skills, print knowledge, and letter-name and letter-sound knowledge.  相似文献   
76.
The purpose of this study was to concurrently examine the development of written language across different writing tasks and to investigate how writing features develop in preschool children. Emergent written language knowledge of 372 preschoolers was assessed using numerous writing tasks. The findings from this study indicate that children demonstrate knowledge about writing before beginning school and receiving formal instruction. There was clear evidence to support the claim that universal writing features develop before language-specific features. Children as young as 3 years possess knowledge regarding universal and language-specific writing features. Preschoolers appear to progress along a continuum from scribbling to conventional spelling. Although this progression is sequential, children’s writing proficiency is task dependent. Implications of these findings on writing development are discussed.  相似文献   
77.
The dramatic changes during the past 20 years in Taiwan offer a good example of how gender policy in education is facilitated by a combination of interrelated economic, political and social forces. Taiwan’s policy on gender education emerged from the interaction of state, education, academic and non‐academic feminist positions in reforms. This paper demonstrates – first, the importance of the socio‐political contexts in which reform was proposed, and second, the actions of feminists in making best use of the opportunities thrown up by a confluence of social factors. The social, economic and political transformations of the 1980s saw the rise of a ‘new’ state both supposedly and in reality more responsive to the needs of non‐profit organisations. In testing out relationships of partnership with the state, feminist activists saw the deregulation of education as an opportunity to get women’s issues on the agenda. These reforms were catalysed by a series of social events bringing together supporters in a mood of celebration, protest or mourning specifically in response to particular events. The struggles, contentions, and negotiations that underlay the eventual approval of gender reform in education are illustrated.  相似文献   
78.
Despite the many benefits of involving undergraduates in research and the growing number of undergraduate research programs, few scholars have investigated the factors that affect faculty members’ decisions to involve undergraduates in their research projects. We investigated the individual factors and institutional contexts that predict faculty members’ likelihood of engaging undergraduates in their research project(s). Using data from the Higher Education Research Institute’s 2007–2008 Faculty Survey, we employ hierarchical generalized linear modeling to analyze data from 4,832 science, technology, engineering, and mathematics (STEM) faculty across 194 institutions to examine how organizational citizenship behavior theory and social exchange theory relate to mentoring students in research. Key findings show that faculty who work in the life sciences and those who receive government funding for their research are more likely to involve undergraduates in their research project(s). In addition, faculty at liberal arts or historically Black colleges are significantly more likely to involve undergraduate students in research. Implications for advancing undergraduate research opportunities are discussed.  相似文献   
79.
80.
The present experiment examined the learning effects of participants self-controlling their receipt of knowledge of results (KR) on all or half of their acquisition trials (50%). For participants who were provided 50% self-control, the first half of their acquisition period consisted of receiving KR on all trials, or according to a faded-KR schedule. Participants practiced a sequential timing task. The results showed that independent of practice condition, participants who self-controlled their KR during the acquisition period demonstrated superior performance compared to the respective yoked conditions in the retention and transfer portion of the experiment. These results extend previous research by suggesting that decreasing the proportion of self-control trials does not compromise learning in a self-controlled context.  相似文献   
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