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961.
Leticia I. RAMíREZ-CAVAZOS Charles JUNGHANNS Rakesh NAIR Diana L. CáRDENAS-CHáVEZ Carlos HERNáNDEZ-LUNA Spiros N. AGATHOS Roberto PARRA 《Journal of Zhejiang University. Science. B》2014,15(4):343-352
研究目的:优化获得血红密孔菌(P.sanguineus)的最佳培养基组成,提高耐热漆酶的产量。创新要点:获得了目前文献报道的最高水平的漆酶活力。研究方法:通过单因素试验研究了不同培养基(番茄汁、麦麸、麦芽提取物和葡萄糖细菌蛋白胨培养基)和不同组合诱导剂(大豆油、阿魏酸、没食子酸、二甲基苯胺、酸性蓝62和活性蓝19分别与硫酸铜组合诱导剂)对P.sanguineus产耐热漆酶的影响。在此基础上采用中心组合试验设计,进一步研究了番茄汁培养基结合硫酸铜和大豆油组合诱导剂对P.sanguineus产耐热漆酶的影响。利用SAS10.0和响应面分析方法对试验结果进行了统计分析和建立回归模型。重要结论:通过中心组合设计优化得出P.sanguineus产耐热漆酶的最优培养基条件:以36.8%番茄汁为培养基,以3 mmol/L硫酸铜和1%大豆油作为组合诱导剂。该条件下在10 L搅拌槽生物反应器中漆酶活力达到了143 000 IU/L(2,2'-联氮双(3-乙基苯并噻唑啉-6-磺酸)为底物,pH值为3.0)。 相似文献
962.
“Tjaa,I Do Have Ears,But I Do Not Hear”: New Literacy Studies and the Awakening of a Hearing Teacher
Karen Rut Gísladóttir 《Studying Teacher Education》2014,10(2):179-194
To address the low literacy achievement of minority students, the sociocultural movement of the New Literacy Studies (NLS) encourages us to expand on current understandings of literacy. Instead of thinking of literacy as a neutral set of skills transferable from one setting to another, NLS researchers encourage us to contextualize literacy within individuals’ social and cultural realms. In this view, there are multiple literacies. As a literacy teacher of students who are deaf, I have witnessed students struggling with school-based literacy learning. As I began to examine what I was doing within the classroom, I realized that my assumptions about literacy instruction were the main source of students' struggles. In this study I explore how I used the theoretical perspective of the NLS to expand my understanding of literacy. The findings suggest that, in order to base literacy instruction on students' resources, teachers need to learn to negotiate conflicting educational Discourses on reading and writing, to create a space within the classroom for students to bring in their literacy practices, and to recognize and preserve students' agency and identity in their learning. Findings also indicate the vital role of writing in deaf students' learning of Icelandic. 相似文献
963.
Tâmile Stella Anacleto Taísa Adamowicz Laura Simões da Costa Pinto Fernando Mazzilli Louzada 《Mind, Brain, and Education》2014,8(4):169-174
Although the environmental light/dark cycle is the main zeitgeber for the human species, the social cues seem to be important in the synchronization of circadian rhythms. In Brazil, the existence of two school schedules—one with only morning classes (MG) and other with only afternoon classes (AG)—allows the investigation of the effect of school activities on light exposure and sleep/wake patterns in children. Forty‐seven children wore wrist actimeters for a week for registration of light and sleep data. MG children presented shorter sleep duration on school days than the children from the AG. The results showed that during school days MG children were exposed to bright light earlier in the morning when compared to AG children. Nevertheless, there were no differences in light exposure after sunset. The results reflect the role of school schedules and artificial light in shaping light exposure, and its association with sleep timing in children. 相似文献
964.
965.
AN Pisarchik R Jaimes-Reátegui C Rodríguez-Flores JH García-López G Huerta-Cuellar FJ Martín-Pasquín 《Journal of The Franklin Institute》2021,358(4):2561-2575
Extreme multistability is the coexistence of a large number of attractors which can be reached by varying initial conditions. In this paper we show how this fascinating phenomenon can be used for secure communication. The main advantage of the communication system based on extreme multistability over a conventional chaos-based communication system is its exceptionally high security. The proposed system consists of two identical six-order oscillators; one in the transmitter and another one in the receiver, each exhibiting the coexistence of a large number of chaotic attractors. The oscillators are synchronized using a private channel through one of the system variables, while the information is transmitted via a public channel through another variable. The information is encrypted by varying the initial condition of one of the state variables in the transmitter using a chaotic map, adhering message packages in a staggered form to the coexisting attractors within the same time series of another state variable, which leads to switching among the coexisting chaotic attractors. To ensure communication security, the duration of the packages is shorter than synchronization time, so that synchronization attacks are ineffective. 相似文献
966.
Patrick Pollok André Amft Kathleen Diener Dirk Lüttgens Frank T. Piller 《Research Policy》2021,50(8):104174
This study adds to the literature on household sector (HHS) innovation by investigating how user and professional designer teams differ in their ability to translate knowledge diversity into collective creative output. We test our hypotheses on a unique data set of more than 5,000 board game design projects conducted by either teams of professional game designers or by hobbyist (user) designers. Our study lends support for the notion that knowledge diversity is a double-edged sword that has opposing effects on the two dimensions of team creativity, novelty and usefulness. We argue and find that teams composed of self-rewarded users in the household sector are better able than teams of professionals to translate the informational benefits of knowledge diversity into novel concepts and game designs. Finally, we find that user teams are in general more likely to create truly creative (i.e. novel and useful) game designs. This particular result emphasizes the relevance of research on HHS innovation and shows that user designers from the HHS are able to conduct collective development work more effectively than teams of professional designers. 相似文献
967.
Johan Hultman Hervé Corvellec Anne Jerneck Susanne Arvidsson Johan Ekroos Clara Gustafsson Fay Lundh Nilsson Niklas Wahlberg 《Research Policy》2021,50(9):104297
In times of major global interconnectedness and environmental change, the pressure to identify, create, and exploit new resources is certain to intensify. Given that there are unavoidable trade-offs, conflicts, and arenas for violence involved when increasingly more material and immaterial things are turned into resources, we call for explicit research on the very process – a process that we label resourcification. The concept of resourcification shifts attention from essentialist queries about the nature of resources to a focus on the social processes through which things are turned into resources. In search of a better understanding of resources in the Anthropocene and, in particular, an understanding about the way resources emerge and are used, resourcification offers a new conceptual framework that allows for a systematic search for knowledge about the diversity of contexts, conditions, modes, and temporalities of resourcification. This Resourcification Manifesto offers a theoretical and empirical framework for a radical and disruptive approach to innovation, sustainability, and management studies and policies. 相似文献
968.
Ladislava Zbiejczuk Suchá Eliška Bartošová Roman Novotný Jiřina Bělehradová Svitáková Tomáš Štefek Eva Víchová 《Library & information science research》2021,43(1):101068
Public libraries have a huge potential to be creators and facilitators of social innovation in communities and society. Qualitative research based on interviews with 27 librarians showed that social innovation in libraries can take the form of educational and cultural activities, leisure and networking activities and social support services. The main goal of the research was to find out what factors support and make these innovations difficult in public libraries. A four-layer model of barriers and stimulators for social innovation is presented, which includes structural, local, organizational and personnel levels. The model could serve to inform librarians, their stakeholders and governments about all levels of barriers and stimulators connected to innovation of library services and social re-positioning of public libraries in the future. 相似文献
969.
Educational ergonomics focuses on the interaction between educational performance and educational design. By improving the design or pointing out the possible problems, educational ergonomics can be utilized to have positive impacts on the student performance and thus on education process. Laptops and tablet computers are becoming widely used by school children and beginning to be used effectively for educational purposes. As the latest generation of laptops and tablet computers are mobile and lightweight compared to conventional personal computers, they support student-centred interaction-based learning. However, these technologies have been introduced into schools with minimal adaptations to furniture or attention to ergonomics. There are increasing reports of an association between increased musculoskeletal (MSK) problems in children and use of such technologies. Although children are among the users of laptops and tablet computers both in their everyday lives and at schools, the literature investigating MSK activities and possible MSK discomfort regarding children using portable technologies is limited. This study reviews the literature to identify published studies that investigated posture, MSK activities, and possible MSK discomfort among children using mobile technologies (laptops or tablet computers) for educational purposes. An electronic search of the literature published in English between January 1994 and January 2014 was performed in several databases. The literature search terms were identified and combined to search the databases. The search results that the resources investigating MSK outcomes of laptop or tablet use of children are very scarce. This review points out the research gaps in this field, and identifying areas for future studies. 相似文献
970.
Jasmín D. Llamas Susana A. López Matthew Quirk 《Journal of Education for Students Placed at Risk》2014,19(3-4):196-214
This study used a mixed-methods approach to examine the effects of the Advancement Via Individual Determination (AVID) program from the student perspective, specifically focusing on factors associated with student resilience. The AVID program aims to close the achievement gap among predominantly minority and low-income students without a family history of college attendance. Qualitative focus groups were conducted to better understand student perceptions of the program and quantitative survey results were used to compare scores on measures of school support, school engagement, and resilience among AVID and non-AVID students. Both qualitative and quantitative results provided evidence suggesting that the AVID program improved school support and engagement, as well as in the development of individual resilience factors, such as self-awareness, problem-solving ability, and self-esteem. Qualitative results also highlight the importance of providing consistency for students in the learning environment. Future directions and recommendations are provided. 相似文献