Theory, Reduction, and Hierarchy

1988 ◽  
Author(s):  
Keith Stewart Thomson
Keyword(s):  
Biological Sciences ◽  
Genetic Variation ◽  
General Concept ◽  
Simple Expression ◽  
Theory Reduction ◽  
Theory Of Evolution ◽  
Special Cases ◽  
Is Theory ◽  
Attack And Defense

Implicit in the reasons given in Chapter 1 for development being ignored until recently as a potential causal factor in evolutionary theory is the general concept of reductionism. It is a strictly reductionistic approach either to believe that phenotypic variation is equivalent to genetic variation, or to act as though this were the case until disproven. Thus, to take but a single example, we find Stebbins (1974), who is avowedly a “strict reductionist,” stating that “in the future all general theories about evolution will have to be based chiefly upon established facts of population and molecular genetics.” Reduction is, of course, a powerful tool, but it is one with which biologists have in general had difficulty, and which in recent years has come under strong attack and defense (see Williams, 1986). The basic reductionist statement with which we are all comfortable is ontological, namely that the processes underlying all living phenomena are reducible to the operation of mechanical causes: there is no irreducible vitalist essence. Reductionism in this sense is unexceptionable and universal in science. The more difficult sort of reductionism to deal with is theory reduction. A simple expression of this would be the statement that the laws of chemistry are all explicable in terms of the laws of physics, or the laws of biology in the laws of chemistry. Nagel (1961) shows that such theory reduction requires that, for example, the laws of chemistry must be deducible from the laws of physics and that the terms and concepts of both sets of laws be “connected” (see, for example, Newton-Smith, 1982; Beckner, 1974). Another way of putting it is that the laws of physics must be of wider scope than the laws of chemistry, which then constitute a series of special cases of the former, under particular boundary conditions. Talking about theory reduction within the biological sciences, where general theories of broad scope are lacking (except the general theory of evolution that all organisms are related by descent), is somewhat pretentious. In the biological sciences we are forced to work more modestly with rules and probabilities rather than grand laws.

Setup and initial testing of an endoscope manipulator system for assistance in transoral endoscopic surgery

2019 ◽  
Vol 64 (3) ◽  
pp. 347-356
Author(s):  
Axel Boese ◽  
Philipp Hündorf ◽  
Christoph Arens ◽  
Daniel T. Friedrich ◽  
Michael Friebe
Keyword(s):  
General Concept ◽  
Single Type ◽  
Transoral Surgery ◽  
Prototype System ◽  
Clinical Workflow ◽  
Posterior Commissure ◽  
Vocal Cords ◽  
Quick Release ◽  
Special Cases ◽  
Microlaryngeal Surgery

Abstract Purpose For the treatment of malignant diseases of the oral cavity and the larynx, a total or partial resection is the standard therapy, while in special cases chemo- and/or external radiation therapy is considered. Transoral access reduces trauma and hospitalization time. Transoral surgery is usually executed using external microscopic imaging. Therefore, the microscope is placed in the visual line of the opening of the mouth and throat. However, specific anatomical structures like the posterior commissure (dorsal end of the vocal cords) are not visible in these procedures. An endoscopic approach can improve this problem. We introduce a new prototype system for endoscopic assisted transoral surgery. Methods Based on clinical observation and discussions with professional users and surgeons, the clinical need was identified and specified. A general concept or an endoscopic manipulator to assist microlaryngeal surgery was designed. For that a steerable rigid endoscope was combined with an actuator that allows translational and rotational movement. A quick release fastener was designed allowing for fast change of the endoscope and independence from its shape and type. The actuator was fixed on a commercially available, semi-active medical holding arm for easy positioning. The holder can be fixed to the standard rails of the surgical table. The piezoelectric drives integrated in the actuator are activated with a foot pedal. This allows easy and fast fine positioning, while the hands are free to perform the surgery with standard instruments for microlaryngeal surgery. Results A prototype of the system for endoscopic assisted transoral surgery was developed. The entire technical setup was tested in terms of usability and performance in a simulated surgical scenario. A basic phantom, representing the throat and vocal cords was created and placed on a surgical table. The system was installed on the table and the clinical workflow of a simulated endoscopic assisted surgery on the vocal cords was performed. The performance of the setup and the procedure success was evaluated by clinical users. Conclusion Fixture of the system on the surgical table is fast and easy due to its low weight and compact design. The medical holder allows a fast initial positioning of the system in front of the phantom patient. An easy insertion and removal of the endoscope was realized using the quick release fastener. The developed endoscope fixation is universally adaptable and not limited to a single type of endoscope. The piezoelectric drives, combined with the foot pedal, allow a precise placement and readjustment of the endoscope during surgery. The use of a multi view endoscope enables a variable view on the surgical situs. The size and shape of the whole setup offer excellent access to the targeted structures. The development was classified beneficial by the clinical users.

Biology and Theology: Contemporary Issues

2016 ◽  
Author(s):  
Celia Deane-Drummond
Keyword(s):  
Biological Sciences ◽  
Intelligent Design ◽  
Evolutionary Biology ◽  
New Technologies ◽  
Ethical Issues ◽  
Natural Theology ◽  
Mirror Image ◽  
Christian Theology ◽  
Theory Of Evolution ◽  
Science And Theology

Contemporary issues in biology and Christian theology are still dominated by the legacy of 19th-century biologist Charles Darwin’s theory of evolution by natural selection. Debates in evolutionary biology in relation to religious belief have been reinforced by historical myths that stress conflict over integration. More conservative branches of Christianity, often allied to particular Protestant traditions, argue for a form of popular theology that attempts to compete with science, namely, creationism. More sophisticated versions of this position may appear under the guise of intelligent design, though creationism and intelligent design are not synonymous. The mirror image of this position has developed among biologists who identify themselves as new atheists, adding further fuel to the fire of an existing controversy. Methodologically speaking, the engagement of biology and theology will depend on different philosophical presuppositions according to basic models of (a) conflict, (b) independence, (c) dialogue, and (d) integration. The biological sciences also have broader relevance to allied subject domains including, for example: (a) ecological, agricultural, animal, and environmental sciences; (b) anthropological, social, and political sciences; (c) medical sciences, including genetic science and embryo development; and (d) new technologies that include bioengineering. Theological engagement with the biological component of each of these domains is particularly intense where there are controversial ethical issues at stake that seem to challenge specific Christian beliefs about human nature or divine purpose. A more positive approach to the biological sciences that draws on research in the constructive systematic theological task, while avoiding historically naïve forms of natural theology, is starting to emerge in the literature. Within Orthodox, Catholic, and Protestant Christian traditions, there is a spectrum of possible positions, such that the field of science and theology as a whole tends to be ecumenical in orientation rather than divided along denominational boundaries. The Catholic and Orthodox churches, however, give greater precedence to official statements by their respective churches that then influence public reception of controversial issues in biology and theology in particular ways.

An assessment of dairy bull station progeny tests carried out at two centres in Britain

1965 ◽  
Vol 65 (3) ◽  
pp. 315-331
Author(s):  
Lucia Pearson
Keyword(s):  
Genetic Variation ◽  
Milk Yield ◽  
Progeny Test ◽  
Selection System ◽  
Fat Percentage ◽  
Special Cases ◽  
Progeny Tests ◽  
Dairy Bull

1. Station progeny tests of twenty-four Ayrshire and twenty-two Friesian bulls were carried out by the British Oil and Cake Mills Ltd. at two centres in Britain between 1953 and 1961. The tests followed the Danish pattern: groups of ten to seventeen daughters were brought to the station approximately 6 weeks before first calving and milked under standardized conditions for an average of 270 days.2. The place of the station system in modern dairy practice in Britain and abroad was discussed.3. Earlier results had suggested that milk yield, butterfat percentage, S.N.F. percentage, milking rate and conception interval should be taken into account in a progeny test.4. Correlations were calculated between the bulls 305-day field ratings for milk yield and fat percentage and their 90- and 270-day station assessments. Possible reasons for the discrepancies were investigated.5. The selection system employed did not appear to lead normally to the choice of heifers whose dams' milk yield or fat percentage differed from the recorded averages for the breed. In two groups of special cases, deviations were apparent but the effect on the accuracy of the station test was shown to be small. It was concluded that bias due to maternal genetic variation was unlikely to be serious in the general case.

Multi-parameter Singular Integrals I: Examples

2017 ◽  
Author(s):  
Brian Street
Keyword(s):  
Singular Integral ◽  
Singular Integrals ◽  
Pseudodifferential Operators ◽  
Integral Operators ◽  
Singular Integral Operators ◽  
Special Cases ◽  
Stratified Lie Groups ◽  
Left And Right ◽  
Flag Kernels

This chapter discusses a few special cases where a theory of multi-parameter singular integral operators has already been developed. These include the product theory of singular integrals, convolution with flag kernels on graded groups, convolution with both the left and right invariant Calderón–Zygmund singular integral operators on stratified Lie groups, and composition of standard pseudodifferential operators with certain singular integrals corresponding to non-Euclidean geometries. The chapter outlines these examples and their applications and relates them to the trichotomy discussed in Chapter 1.

Limits of imagination: the 150th Anniversary of Mendel’s Laws, and why Mendel failed to see the importance of his discovery for Darwin’s theory of evolution

Genome ◽  
2015 ◽  
Vol 58 (9) ◽  
pp. 415-421 ◽  
Author(s):  
Rama S. Singh
Keyword(s):  
Genetic Variation ◽  
Quantum Mechanics ◽  
Niels Bohr ◽  
One Dimension ◽  
Evolutionary Significance ◽  
Theory Of Evolution ◽  
Determining Factors ◽  
Random Segregation ◽  
Hybrid Development ◽  
Mendel’S Laws

Mendel is credited for discovering Laws of Heredity, but his work has come under criticism on three grounds: for possible falsification of data to fit his expectations, for getting undue credit for the laws of heredity without having ideas of segregation and independent assortment, and for being interested in the development of hybrids rather than in the laws of heredity. I present a brief review of these criticisms and conclude that Mendel deserved to be called the father of genetics even if he may not, and most likely did not, have clear ideas of segregation and particulate determiners as we know them now. I argue that neither Mendel understood the evolutionary significance of his findings for the problem of genetic variation, nor would Darwin have understood their significance had he read Mendel’s paper. I argue that the limits to imagination, in both cases, came from their mental framework being shaped by existing paradigms—blending inheritance in the case of Darwin, hybrid development in the case of Mendel. Like Einstein, Darwin’s natural selection was deterministic; like Niels Bohr, Mendel’s Laws were probabilistic—based on random segregation of trait-determining “factors”. Unlike Einstein who understood quantum mechanics, Darwin would have been at a loss with Mendel’s paper with no guide to turn to. Geniuses in their imaginations are like heat-seeking missiles locked-in with their targets of deep interests and they generally see things in one dimension only. Imagination has limits; unaided imagination is like a bird without wings — it goes nowhere.

scholarly journals A Contextualização Histórica da Evolução em Livros Didáticos de Ciências

2020 ◽  
Vol 21 ◽  
pp. 87-102
Author(s):  
Rafael Cava Mori ◽  
Jessica Amanda Lourenço Dos Santos ◽  
Gabriel Nardy Klein ◽  
Waldir Stefano
Keyword(s):  
Biological Sciences ◽  
Charles Darwin ◽  
School Science ◽  
Sao Paulo ◽  
São Paulo ◽  
National Program ◽  
Science Textbooks ◽  
Theory Of Evolution ◽  
Historical Contextualization ◽  
Conceptual Profile

ResumoMuitos educadores concordam que os conteúdos da educação científica escolar devam ser contextualizados historicamente. Com base nisso, este trabalho analisou a presença da contextualização histórica da teoria da evolução, nos três livros didáticos de Ciências (séries finais do ensino fundamental) mais presentes em escolas do Estado de São Paulo (2017-2019). Foram tomadas em consideração tanto discussões historiográficas sobre esses conteúdos quanto a noção de perfil conceitual sobre adaptação. A análise abordou elementos textuais e imagéticos, identificando as seguintes características na abordagem de evolução nos livros: predominância de Charles Darwin entre os estudiosos mencionados; imprecisões históricas, principalmente nas exposições sobre outros naturalistas que contribuíram para a teoria evolutiva; apropriações livres, quanto a prescrições curriculares oficiais; hibridização discursiva e relativa variedade de atividades propostas; e contribuições para o fortalecimento das zonas transformacional e variacional, quanto ao perfil conceitual de adaptação, sem tentativas de deslegitimação das zonas do funcionalismo intra-orgânico e do ajuste providencial. Conclui-se que a tradição dos manuais escolares, quanto à presença da contextualização histórica nos conteúdos de evolução, permanece representada pelos livros analisados, junto de tentativas de atualizações.Palavras-chave: Programa Nacional do Livro Didático; adaptação; ensino de ciências biológicas.AbstractMany educators agree that the contents of school science education should be historically contextualized. Based on this, the present article analyzed the presence of historical contextualization in the theory of evolution in three Science textbooks (final grades of primary school) most commonly found in schools in the state of São Paulo (2017-2019). We took into account both the historiographic discussions about these contents and the notion of conceptual profile about adaptation. Our analysis addressed textual and imagery elements, identifying the following characteristics in the way evolution is approached in the books: a predominance of Charles Darwin among the researchers mentioned; historical inaccuracies, particularly in the expositions on other naturalists who contributed to evolutionary theory; free appropriation regarding official curricular prescriptions; discursive hybridization and a relative variety of activities proposed; and contributions to the strengthening of the transformational and variational zones regarding the conceptual profile of adaptation, without attempts to delegitimize the intra-organic functionalism and providential adjustment zones. We conclude that, with regard to the presence of historical contextualization of evolution, the tradition of school textbooks is still represented by the textbooks analyzed, along with updating.Keywords: Brazilian National Program of Textbooks; adaptation; teaching of biological sciences.

scholarly journals The gamma exponentiated exponential-Weibull distribution

Filomat ◽  
2016 ◽  
Vol 30 (12) ◽  
pp. 3159-3170 ◽  
Author(s):  
Tibor Pogány ◽  
Abdus Saboor
Keyword(s):  
Biological Sciences ◽  
Weibull Distribution ◽  
Goodness Of Fit ◽  
Data Sets ◽  
Fit Statistics ◽  
Positive Data ◽  
Special Cases ◽  
Likelihood Approach ◽  
Anderson Darling ◽  
Von Mises

Anewfour-parameter model called the gamma-exponentiated exponential-Weibull distribution is being introduced in this paper. The new model turns out to be quite flexible for analyzing positive data. Representations of certain statistical functions associated with this distribution are obtained. Some special cases are pointed out as well. The parameters of the proposed distribution are estimated by making use of the maximum likelihood approach. This density function is utilized to model two actual data sets. The new distribution is shown to provide a better fit than related distributions as measured by the Anderson-Darling and Cram?r-von Mises goodness-of-fit statistics. The proposed distribution may serve as a viable alternative to other distributions available in the literature for modeling positive data arising in various fields of scientific investigation such as the physical and biological sciences, hydrology, medicine, meteorology and engineering.

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