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161.
Diversity of Gram negative bacteria antagonistic against major pathogens of rice from rice seed in the tropic environment 总被引:2,自引:0,他引:2
INTRODUCTIONRiceseedharborsadozenofplantpathogen icbacteria (Gotoetal.,1 988;Xieetal.,1 998) .Thebacterialpathogenscausearangeofricediseases,someverydestructivewhileothershavenoeffectonricecropgrowth .Inthisstudy ,wefoundalargenumberofbacteriaasso ciatedw… 相似文献
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Peer relations across 2 contexts (in school and after school) were examined for 577 participants, approximately 12 years old, from 3 middle schools in Milan, Italy. The primary research questions were: Do peer networks from different contexts uniquely contribute to explaining variance in individual behavior? Do measures of peer preference and peer network inclusion across contexts uniquely contribute to explaining individual depressive symptoms? Structural equation models showed that both the in-school and the after-school peer networks uniquely contributed to explaining variance in 2 types of individual problem behavior (in-school problem behavior, after-school delinquency), and that similarity with the 2 peer networks varied according to behaviors specific to each context and across gender. Finally, both in-school and after-school peer network inclusion contributed to explaining variance in depressive symptoms, after controlling for classroom peer preference. 相似文献
164.
To obtain confirmation of the findings of the authors' earlier comparison of ever-pregnant and nonpregnant Black high school students from Tennessee, 16 students confirmed to be pregnant were substituted for the 33 subjects in the original study whose pregnancy status was based solely on self-report. The nonpregnant control group of 251 teens was utilized in both analyses. Although the confirmed pregnant group was too small to repeat the regression analysis, striking concordance of findings between the 2 studies emerged for all dependent variables except the Eysenck Personality Questionnaire anxiety scale. The lower anxiety scores recorded among subjects in the original study may be either a statistical artifact or a reflection of the fact that these pregnant teens remained in school while subjects in the second study were enrolled in programs centered around their pregnant status. Sexual activity scores were strong or moderate significantly more often in both groups of pregnant teens compared to their nonpregnant counterparts. Interesting was the finding that 81% of pregnant teens regarded romance novels and soap operas to be accurate portrayals of real-life dating relationships compared to only 49% of nonpregnant teens. On the other hand, only 56% of the pregnant subjects regarded their own relationships to have this romantic quality. In a future study, the role of such uncritical romantic ideals in adolescent pregnancy risk will be investigated in a larger sample. 相似文献
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Arandom sample of directors of programs for the deaf in North America were surveyed to get their views about the skills that teacher education programs need to be teaching future teachers of students who are deaf or hard of hearing. The directors were queried about literacy practices, classroom management strategies, and communication strategies used in their programs, and were encouraged to comment freely on the questionnaire items presented to them. Program directors predicted a need for more itinerant and resource teachers. The survey also revealed that programs for the deaf are highly behaviorist (i.e., You do this and you'll get that) in the way they induce students to learn and in how they manage student behavior. 相似文献
168.
Burnham D Leigh G Noble W Jones C Tyler M Grebennikov L Varley A 《Journal of deaf studies and deaf education》2008,13(3):391-404
Caption rate and text reduction are factors that appear to affect the comprehension of captions by people who are deaf or hard of hearing. These 2 factors are confounded in everyday captioning; rate (in words per minute) is slowed by text reduction. In this study, caption rate and text reduction were manipulated independently in 2 experiments to assess any differential effects and possible benefits for comprehension by deaf and hard-of-hearing adults. Volunteers for the study included adults with a range of reading levels, self-reported hearing status, and different communication and language preferences. Results indicate that caption rate (at 130, 180, 230 words per minute) and text reduction (at 84%, 92%, and 100% original text) have different effects for different adult users, depending on hearing status, age, and reading level. In particular, reading level emerges as a dominant factor: more proficient readers show better comprehension than poor readers and are better able to benefit from caption rate and, to some extent, text reduction modifications. 相似文献
169.
The current study examined whether parental and contextual risk factors contribute to mothers' and fathers' differential treatment (MDT/FDT) when accounting for sibling dyad characteristics. Also explored was whether family type (single mothers vs. 2 parents) moderated the links between the parental and contextual correlates and MDT. One hundred and seventy-two families with older (M= 7.4 years) and younger (M= 5.2 years) siblings were studied. Parents and children reported about the parent-child relationship, and parents reported about the children's characteristics, their own psychological resources, and contextual factors. Controlling for sibling dyad characteristics, FDT was predicted most consistently by household chaos. Furthermore, single mothers were not at risk per se for using more MDT but only when coupled with high maternal anger. 相似文献