Conditions for a theoretical biology: is biology truly an autonomous science?

In a line of a previous paper, the conditions for a theoretical biology were discussed and it was pointed out that the primary condition is that biology is an autonomous science. This statement is connected to the problem of reductionism. A discussion of the autonomy of biology shows that reductionism cannot be maintained, although particularly in physiology often physics and mathematics are used. Development, organization and evolution of biological systems are typical areas of autonomous biological researches and of autonomous theoretical developments. A sort of reduction to history seems today a nonsensical attempt to reduce the area of free theoretical biological activity.     

Unquiet Evolution: Consideration of a Previous Synthesis

The mathematics in school biology is investigated by means of an analysis of the questions in examination papers set over a period of time in biological subjects by the University of London Examinations Board. Throughout, the incidence of questions requiring mathematics changes but remains low, while the range of mathematics topics called upon remains both restricted and unchanging. However, the various biological examination subjects differ markedly with respect both to the changes in the incidence of such questions and to the range and frequency with which the topics are used.

Certain difficulties associated with the mathematics of school biology are identified, and biology teachers are encouraged to discuss these with their colleagues who teach mathematics.     

Report on the round-table discussion of the subject "idea and experience" in connection with the 1977 annual meeting "process kinetics" of the German Academy of Natural Scientists Leopoldina (Halle/S., October 16, 1977)]

A report is given about a round-table-discussion upon the role and meaning of "idea and experience" in the creative scientific process. Notable representatives of mathematics, theoretical physics and geophysics, chemistry, theoretical and general experimental biology, and of medicine contribute in the discussion guided by C. F. V. WEIZSACKER to this theme from point of view of their disciplines. The components of meaning of "idea and experience" in their connection one to another may be paraphrased by such pairs of terms as "theory and practice", "theoretical or empirical", "law and appearance of a single phenomenon", "unity and diversity", abstract and concrete". It was demonstrated that in each of the mentioned scientific disciplines there is a natural, and that, starting from mathematics and going to biology and medicine, the weight in that relation will shift more and more to "experience". Many of the known methodological problems and difficulties will arise in the mentioned scientific branches if one stresses immoderately only one component of "idea and experience" by leaving the natural, discipline-related range of variation of the relation "idea and experience".     

Mechanics as an aid to interpreting pollen structure and function

Pollen walls can be viewed, like all other structural entities, as bodies subject to the laws of mathematics and mechanics. This view is compatible with an interpretation of pollen biology in terms of water relations. Some basic mathematical and mechanical relationships are discussed, including scaling effects, and these applied to Compositae pollen.     

The Mathematical Basis of Mendelian Genetics

In a climate where increasing numbers of students are encouraged to pursue post-secondary education, the level of preparedness students have for college-level coursework is not far from the minds of all educators, especially high school teachers. Specifically within the biological sciences, introductory biology classes often serve as the gatekeeper or a pre-requisite for subsequent coursework in those fields and pre-professional programmes (eg pre-medicine or pre-veterinarian). Thus, how helpful high school science and mathematics experiences are in preparing students for their introductory biology classes is important and relevant for teachers, science educators and policy makers alike. This quantitative study looked at the association between students' high school science and mathematics experiences with introductory college biology performance. Using a nationally representative sample of US students (n?=?2667) enrolled in 33 introductory college biology courses, a multi-level statistical model was developed to analyse the association between high school educational experiences and the final course grade in introductory biology courses. Advanced high school science and mathematics coursework, an emphasis on a deep conceptual understanding of biology concepts and a prior knowledge of concepts addressed in well-structured laboratory investigations are all positively associated with students' achievement in introductory college biology.     

Bringing mathematics to Life

Some of the more recently introduced topics in the school mathematics curriculum could be of value in teaching school biology. Two, namely enlargement and the cartesian product, are mentioned, and instances concerning the former are given by way of illustration. Growth in size in biology is considered from the point of view of enlargement in mathematics. Essential features of enlargement are identified and used to answer questions concerning the growth of leaves and the scale of drawings and of magnified images. It is suggested that materials of this kind could form a useful basis for interdisciplinary studies and for discussion between teachers of biology and of mathematics.     

Structure brings clarity: Structured illumination microscopy in cell biology

Biological samples are three dimensional and, therefore, optical sectioning is mandatory for microscopic images to precisely show the localization or function of structures within biological samples. Today, researchers can choose from a variety of methods to obtain optical sections. This article focuses on structured illumination microscopy, which is a group of techniques utilizing a combination of optics and mathematics to obtain optical sections: A structure is imaged onto the sample by optical means and the additional information thereby encoded in the image is used to calculate an optical section from several acquired images. Different methods of structured illumination microscopy (mainly grid projection and aperture correlation) are discussed from a practical point of view, concentrating on advantages, limitations and future prospects of these techniques and their use in cell biology. Structured illumination can also be used to obtain super-resolution information if structures of higher frequency are projected onto the sample. This promising approach to super-resolution microscopy is also briefly discussed from a user's perspective.     

弱激光的生物学效应及对红细胞变形性的改善作用

简要叙述激光生物效应和弱激光生物刺激作用。概括阐述激光照射血液所产生的生物学效应,叙述了弱激光对红细胞变形性的改善作用并探讨其可能的作用机理。     

Cancer as an emergent phenomenon in systems radiation biology

Radiation-induced DNA damage elicits dramatic cell signaling transitions, some of which are directed towards deciding the fate of that particular cell, while others lead to signaling to other cells. Each irradiated cell type and tissue has a characteristic pattern of radiation-induced gene expression, distinct from that of the unirradiated tissue and different from that of other irradiated tissues. It is the sum of such events, highly modulated by genotype that sometimes leads to cancer. The challenge is to determine as to which of these phenomena have persistent effect that should be incorporated into models of how radiation increases the risk of developing cancer. The application of systems biology to radiation effects may help to identify which biological responses are significant players in radiation carcinogenesis. In contrast to the radiation biology paradigm that focuses on genomic changes, systems biology seeks to integrate responses at multiple scales (e.g. molecular, cellular, organ, and organism). A key property of a system is that some phenomenon emerges as a property of the system rather than of the parts. Here, the idea that cancer in an organism can be considered as an emergent phenomenon of a perturbed system is discussed. Given the current research goal to determine the consequences of high and low radiation exposures, broadening the scope of radiation studies to include systems biology concepts should benefit risk modeling of radiation carcinogenesis. Presented at the First International Workshop on Systems Radiation Biology, February 14–16 2007, GSF-Research Centre, Neuherberg, Germany.     

Bionomics dynamic model of a class of competition systems ☆

Differential equation problem is an important research topic in the international academia. In accordance with certain ecological phenomena, previous research was conducted based on simple observational and statistical data. But this approach does not effectively study the essence of the ecological phenomena. Recently, one dynamic approach has been proposed for the study of ecology in the international academia. According to this approach, first of all, the ecology is reduced to the differential equation model which represents the essential phenomenon, and then the dynamic law and rules of mathematics and biology will be studied. Currently, an extensive research is conducted on the differential equation problem. This paper primarily explores a type of competitive ecological model, which is a system of differential equation with infinite integral. we first study the existence of positive periodic solution to this model, and then present sufficient conditions for the global attractivity of positive periodic solutions.     

机器学习方法在基因功能注释中的应用

目前,基于计算机数学方法对基因的功能注释已成为热点及挑战,其中以机器学习方法应用最为广泛。生物信息学家不断提出有效、快速、准确的机器学习方法用于基因功能的注释,极大促进了生物医学的发展。本文就关于机器学习方法在基因功能注释的应用与进展作一综述。主要介绍几种常用的方法,包括支持向量机、k近邻算法、决策树、随机森林、神经网络、马尔科夫随机场、logistic回归、聚类算法和贝叶斯分类器,并对目前机器学习方法应用于基因功能注释时如何选择数据源、如何改进算法以及如何提高预测性能上进行讨论。     

全错位排列问题的基于表面的DNA计算模型

生物表面技术是DNA计算的一种实现方式,是近年来生命科学的新兴研究领域．而全错位排列问题作为组合数学中一个重要的问题,到目前为止还没有好的算法．在DNA表面技术的基础上,首次提出了全错位排列问题的基于表面的DNA计算模型,并对模型进行了简单的分析．