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991.
In two experiments, we examined how preexposure to discriminative stimuli and introduction of a 21-day retention interval affected the latent inhibition (LI) and perceptual learning (PL) of rats in a choice-maze discrimination task. Experimental groups were preexposed to three wall patterns, one in each of three arms of a maze. Control groups were preexposed only to white arms. PL groups were trained to discriminate A versus B, and LI groups, to discriminate A or B versus C. The A and B patterns shared many elements not shared with the C pattern. In Experiment 1, both at the end of training and after the subsequent retention interval, the PL groups performed better than controls, whereas the LI groups performed worse. In Experiment 2, inserting the 21-day retention interval between preexposure and discrimination training disrupted final measures of LI but not PL performance. Implications for current concepts of PL and LI are discussed.  相似文献   
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993.
    
This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency (45% and 36% respectively), as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.  相似文献   
994.
The aim of the present study was to understand the nature of teaching efficacy beliefs related to a socioscientific issue (SSI). We investigated Turkish preservice science teachers’ teaching efficacy beliefs about genetically modified (GM) foods using a belief system approach. We assumed that preservice teachers’ beliefs about GM foods (content knowledge, risk perceptions, moral beliefs, and religious beliefs) and their teaching efficacy beliefs about this topic constitute a belief system, and these beliefs are interrelated due to core educational beliefs. We used an exploratory mixed design to test this model. We developed and administered specific questionnaires to probe the belief system model. The sample for the quantitative part of this study included 441 preservice science teachers from eight universities. We randomly selected eight participants in this group for follow-up interviews. The results showed that preservice science teachers held moderately high teaching efficacy beliefs. Learning and teaching experiences, communication skills, vicarious experiences, emotional states, and interest in the topic were sources of this efficacy. In addition, content knowledge and risk perceptions were predictors of teaching efficacy. We believe that epistemologies based on traditional teaching and the values attached to science teaching are the core beliefs that affect the relationship between predictor variables and teaching efficacy.  相似文献   
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996.
    
The digital revolution has shaped the modern world in unprecedented ways. Moreover, the COVID-19 pandemic has highlighted the value of digital technologies. As the health crisis’ effect rippled through economic, political, and social structures worldwide, it also accelerated the adoption of digital tools to pool expertise, ideas, and capacities for generating solutions to the pandemic’s short- and long-term implications. One of the areas where major challenges have arisen is employment.In the whole panorama of digital social innovation in Spain, we find an experience that can be described as outstanding and that links employment and digitalization. However, despite being highly successful, there is hardly any academic literature on this experience. The Connect Employment Shuttles will be the subject of specific in-depth analysis in this article. This is a socially innovative program that has been developed since 2020 in collaboration with the Santa María la Real Foundation. The Connect Employment Shuttles are an existing model specialization, the Employment Shuttles, but applied in the field of digitalization. In this article, we present the origin of the Employment Shuttles and the differences between them and other labor market integration initiatives, their constituent elements, and the social impact they exert.The research question of our study is whether this innovative mechanism combining employment and digitalization is valid and reliable. The answer is particularly relevant for private and public entities interested in implementing effective measures against unemployment, especially in vulnerable groups. The main contribution of this study is the systematized presentation of the experience of the Connect Employment Shuttles and its results so far, being the major limitation is the scarcity and dispersion of information sources.  相似文献   
997.
Orthographic knowledge, the general ability to learn, store, and use information about the orthographic form of words (Stanovich & West, 1989), is a crucial skill for supporting literacy. Although the development of first language (L1) orthographic awareness is impacted by the characteristics of a learner’s L1 writing system, relatively little is known about what impact the L1 may have on second language (L2) orthographic awareness. In this study, English language learners from three L1s (French, Hebrew, Mandarin Chinese), plus L1 English speakers, were tested on their English spelling knowledge using a word-pseudohomophone discrimination task. In addition to allowing for the cross-linguistic comparisons, items were designed to examine whether learners had differing performance on pseudohomophones (misspellings) that targeted vowels versus consonants. Consistent with previous research (e.g., McBride-Chang, Bialystok, Cong, & Li, 2004), the L1 Chinese speakers had the highest (L2) accuracy, followed by the L1 Hebrew and the L1 French speakers. The participants from non-alphabetic languages (Hebrew and Chinese) had significantly lower accuracy on items with misspellings involving vowels compared to consonants, and the size of the vowel-consonant accuracy difference varied substantially across L1 groups. The results demonstrate that the characteristics of a learner’s L1 writing system, particularly the existence of vowel and consonant graphemes, impact the development of L2 orthographic knowledge and sensitivity to different types of word misspellings.  相似文献   
998.
INTRODUCTION Let w be the set of all sequences of real or com- plex numbers and R∞, c and c0 be the sequence spaces of bounded, convergent and null sequences x=(xk), respectively. A sequence x∈R∞ is said to be almost convergent (Lorentz, 1948) if all Banach limits of x coincide. Lorentz (1948) proved that 1 c? = ??? x =( xk ) :linm 1n ∑kn= xk s exists, uniformly in s???. Maddox (1967; 1978) has defined x to be strongly almost convergent to a number L if 1 linm 1n ∑k n= xk s? L=0,…  相似文献   
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