集群式计算机系统在生物信息学中的应用

1　Introduction　SMP (symmetricmulti processing)andMPP (mas sivelyparallelprocessing)arethetwotypesofstruc tureofparallelcomputing .　Symmetricmulti processingsystemshavemultipleCPUsattachedtothesamebusandsharingRAM .Massivelyparallelprocessingisthecooperated pro cessingofaprogrambymultipleprocessorsthatworkondifferentpartsoftheprogram ,witheachprocessorusingitsownoperatingsystemandmemory .ThechoicebetweenSMPandMPPdependsonthenatureoftheproblembeingsolved .Iftheproblemcanbeeasilypartit…     

Optimal restructuring strategies under various dynamic factors

Corporate restructuring was identified as a new industrial force that has great impact on economic values and that therefore has become central in daily financial decision making. This article investigates the optimal restructuring strategies under different dynamic factors and their numerous impacts on firm value. The concept of quasi-leverage is introduced and valuation models are built for corporate debt and equity under imperfect market conditions. The model＇s input variables include the quasi-leverage and other firm-specific parameters, the output variables include multiple corporate security values. The restructuring cost is formulated in the form of exponential function, which allows us to observe the sensitivity of the variation in security values. The unified model and its analytical solution developed in this research allow us to examine the continuous changes of security values by dynamically changing the coupon rates, riskless interest rate, bankruptcy cost, quasi-leverage, personal tax rate, corporate taxes rate, transaction cost, firm risk, etc., so that the solutions provide useful guidance for financing and restructuring decisions.     

Distributed Cognition as a Lens to Understand the Effects of Scaffolds: The Role of Transfer of Responsibility

Problem solving is an important skill in the knowledge economy. Research indicates that the development of problem solving skills works better in the context of instructional approaches centered on real-world problems. But students need scaffolding to be successful in such instruction. In this paper I present a conceptual framework for understanding the effects of scaffolding. First, I discuss the ultimate goal of scaffolding—the transfer of responsibility—and one way that scholars have conceptualized promoting this outcome (fading). Next, I describe an alternative way to conceptualize transfer of responsibility through the lens of distributed cognition and discuss how this lens informs how to promote transfer of responsibility. Then I propose guidelines for the creation of problem solving scaffolds to support transfer of responsibility and discuss them in light of the literature.     

Theory to reality: a few issues in implementing problem-based learning

The success of an intervention depends not only upon its theoretical soundness, but also on proper implementation that reflects the guidelines derived from its theoretical conception. Debates surrounding the effectiveness of problem-based learning (PBL) have focused on its theoretical conception and students’ learning outcomes, but implementation is seemingly absent from the picture. This paper attempts to describe what research evidence is needed to fill in this missing information and provide a clearer picture of PBL. The author examines current PBL implementation practices and identifies potentially confounding variables that may play a role in inconsistent or conflicting research results in PBL. For example, various models of PBL have been developed and implemented to afford the specific instructional needs of the institution or learner population. These PBL models are in fact quite different in terms of the nature of problem solving and the degrees of self-directed learning, which theoretically, should result in different types of learning outcomes. Without distinguishing the models used, the results of comparative PBL research could have been confounded. Furthermore, human factors are another set of confounding variables that could influence the students’ learning processes and consequently affect PBL implementations and research results. To remedy these problems and reach PBL’s full potential, as well as obtain a more accurate picture of PBL as an instructional method and its effects on students’ learning, some fundamental changes are needed.     

The Challenges Facing Early Childhood Care,Development and Education (ECCDE) in an Era of Universal Basic Education in Nigeria

Early childhood is a critical period of rapid physical, cognitive, and psycho-social development of a child. The quality of care and education which a child receives at this crucial age will determine to a great extent the level of his/her physical and cognitive development in the future. In Nigeria, Early Childhood Care, Development and Education (ECCDE) is an aspect of Universal Basic Education which was introduced in 1999 to increase the access of children to basic education and improve the state of education in the country. While all hands are on deck to ensure successful implementation and achievement of the objectives of the scheme, it is unfortunate that ECCDE is facing some challenges thus making it unrecognized in Nigeria. This paper examines the challenges of early childhood education in Nigeria. To improve the situation, the following measures are recommended: establishment of more public crèche, kindergarten, and nursery schools by the government; enforcement of the use of mother tongue in the teaching of children; training more personnel in the field of early childhood education in tertiary institutions; and introducing unified curriculum as well as providing more infrastructures.     

Young Voices on Climate Change: The Paul F-Brandwein 2010 NSTA Lecture

Lynne Cherry Brandwein Lecture March 2010 National Science Teachers Association (NSTA) Conference, Philadelphia, PA. Young Voices on Climate Change: Inspired and Empowered Youth Tackle Climate Science and Find Climate Solutions. As a child, Lynne Cherry was profoundly connected to the natural world and a special place. She watched the destruction of her world. Now, through her Young Voices on Climate Change project, she is trying to give teachers and young people the tools to prevent planetary meltdown on a greater scale. Global climate change is upon us and the need for education and action is immediate. Outreach, visual storytelling, and scientific understanding are especially necessary in light of the recent polls that show that the public is becoming more confused and less concerned about climate change. Cherry’s climate book, co-authored with photojournalist Gary Braasch, and her Young Voices on Climate Change films feature climate solutions. They’re about win–win—save the environment, protect human health, reduce global warming gases, demonstrate youth making a difference with practical tools, motivate engagement in climate science, take pride in increased science literacy, reach young people through their hearts as well as their minds, and save money. Although young people can help their parents, peers and communities understand climate science, they can also show them that reducing CO₂ is in their economic interest, and spur them to take action. School carbon reduction initiatives are spilling over into communities yielding measurable results in both global warming gas reductions and significant monetary savings.     

Reclaiming Kindergarten: Part II: Questions About Policy

Part II of “Reclaiming Kindergarten” continues the discussion related to responding to the crisis in today’s kindergarten. In Part II, two policy questions are posed, the answers to which seek to respond to this continuing crisis. The questions center on issues related to engaging families in kindergarten and the need to consider a new early childhood paradigm where kindergarten is part of a continuous and seamless educational experience spanning prekindergarten through third grade. As in Part I, examples of classroom practice are used to illustrate the effective implementation of these principles in a kindergarten classroom.     

Transforming Teacher Constructs of Children and Families Who Are Homeless

The focus of this article is on articulating the importance of teacher development of constructs about homeless children and families and examining factors that influence teachers’ perceptions of children and families who are homeless or at high-risk of becoming homeless. The article also explores some strategies to support teachers in transforming their perceptions of homeless children and provides case examples of how this process can work. Three case studies explore how teacher educators and practicing teachers can work together to reflect on their own perceptions of homeless children from high-poverty backgrounds and how educators were able to transform their own perceptions in being able to better serve their students.     

Enjoying A Good Story: Why We Use Children’s Literature When Teaching Adults

Early childhood teacher educators frequently enhance their teaching by reading children’s books to their adult students. It is not unusual for faculty outside of early childhood to question devoting precious class time to read-alouds which they may consider a curious, if not frivolous, instructional strategy. Quality children’s literature can, however, enhance students’ experiences in the college classroom, contribute to their understanding of course content, promote their personal growth and self-understanding, increase their appreciation for quality children’s literature, and enhance their ability to integrate storybooks into their own teaching. Children’s books often capture a child’s point of view. They have the potential to provide historical or cultural perspectives on children and families. They also can lead to the examination of universal truths and can facilitate the discussion of sensitive or emotional issues A list of books with suggested uses is included.     

Neuroscience,Early Childhood Education and Play: We are Doing it Right!

This editorial examines neuroscience and its impact on the field of education. Starting with a narrative between two young children, the author intertwines research with basic principles of learning, using the interaction between two 4-year-olds to illustrate the precepts. The four principles are: (1) the brain is uniquely organized; (2) the brain is continually growing; (3) a “brain-compatible” classroom enables connection of learning to positive emotions; and (4) children’s brains need to be immersed in real-life, hands-on, and meaningful learning experiences. The editorial concludes with an illustration of how the brain works while two children are playing at the small animal center in their classroom.