Sample records for biologically active principles

  1. Efficiently Photocontrollable or not? Biological Activity of Photoisomerizable Diarylethenes.

    PubMed

    Komarov, Igor V; Afonin, Sergii; Babii, Oleg; Schober, Tim; Ulrich, Anne S

    2018-04-06

    Diarylethene derivatives, whose biological activity can be reversibly changed by irradiation with light of different wavelengths, have shown promise as scientific tools and as candidates for photocontrollable drugs. However, examples demonstrating efficient photocontrol of their biological activity are still relatively rare. This concept article discusses the possible reasons for this situation and presents a critical analysis of existing data and hypotheses in this field, in order to extract the design principles enabling the construction of efficient photocontrollable diarylethene-based molecules. Papers addressing biologically relevant interactions between diarylethenes and biomolecules are analyzed; however, in most published cases, the efficiency of photocontrol in living systems remains to be demonstrated. We hope that this article will encourage further discussion of design principles, primarily among pharmacologists and synthetic and medicinal chemists. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Problem-Centered Supplemental Instruction in Biology: Influence on Content Recall, Content Understanding, and Problem Solving Ability

    NASA Astrophysics Data System (ADS)

    Gardner, Joel; Belland, Brian R.

    2017-08-01

    To address the need for effective, efficient ways to apply active learning in undergraduate biology courses, in this paper, we propose a problem-centered approach that utilizes supplemental web-based instructional materials based on principles of active learning. We compared two supplementary web-based modules using active learning strategies: the first used Merrill's First Principles of Instruction as a framework for organizing multiple active learning strategies; the second used a traditional web-based approach. Results indicated that (a) the First Principles group gained significantly from pretest to posttest at the Remember level ( t(40) = -1.432, p = 0.08, ES = 0.4) and at the Problem Solving level ( U = 142.5, N1 = 21, N2 = 21, p = .02, ES = 0.7) and (b) the Traditional group gained significantly from pretest to posttest at the Remember level ( t(36) = 1.762, p = 0.043, ES = 0.6). Those in the First Principles group were significantly more likely than the traditional group to be confident in their ability to solve problems in the future (χ2 (2, N = 40) = 3.585, p = 0.09).

  3. [How to be prudent with synthetic biology. Synthetic Biology and the precautionary principle].

    PubMed

    Rodríguez López, Blanca

    2014-01-01

    Synthetic biology is a new discipline that is twofold: firstly it offers the promise to pay benefits that can alleviate some of the ills that plague mankind; On the other hand, like all technologies, holds risks. Given these, the most critical and concerned about the risks, invoke the application of the precautionary principle, common in cases where an activity or new technology creates risks to the environment and/or human health, but far from universally accepted happens to be currently one of the most controversial principles. In this paper the question of the risks and benefits of synthetic biology and the relevance of applying the precautionary principle are analyzed. To do this we proceed as follows. The first part focuses on synthetic biology. At first, this discipline is characterized, with special attention to what is novel compared to the known as "genetic engineering". In the second stage both the benefits and the risks associated with it are discussed. The first part concludes with a review of the efforts currently being made to control or minimize the risks. The second part aims to analyze the precautionary principle and its possible relevance to the case of Synthetic Biology. At first, the different versions and interpretations of the principle and the various criticisms of which has been the subject are reviewed. Finally, after discarding the Precautionary Principle as an useful tool, it is seen as more appropriate some recent proposals to treat technologies that take into account not only risks but also their benefits.

  4. Building Better Scientists through Cross-Disciplinary Collaboration in Synthetic Biology: A Report from the Genome Consortium for Active Teaching Workshop 2010

    ERIC Educational Resources Information Center

    Wolyniak, Michael J.; Alvarez, Consuelo J.; Chandrasekaran, Vidya; Grana, Theresa M.; Holgado, Andrea; Jones, Christopher J.; Morris, Robert W.; Pereira, Anil L.; Stamm, Joyce; Washington, Talitha M.; Yang, Yixin

    2010-01-01

    Synthetic biology is the application of engineering and mathematical principles to develop novel biological devices and circuits. What separates synthetic biology from traditional molecular biology is the development of standardized interchangeable DNA "parts," just as advances in engineering in the nineteenth century brought about standardized…

  5. Problem-Centered Supplemental Instruction in Biology: Influence on Content Recall, Content Understanding, and Problem Solving Ability

    ERIC Educational Resources Information Center

    Gardner, Joel; Belland, Brian R.

    2017-01-01

    To address the need for effective, efficient ways to apply active learning in undergraduate biology courses, in this paper, we propose a problem-centered approach that utilizes supplemental web-based instructional materials based on principles of active learning. We compared two supplementary web-based modules using active learning strategies: the…

  6. Predicting green: really radical (plant) predictive processing

    PubMed Central

    Friston, Karl

    2017-01-01

    In this article we account for the way plants respond to salient features of their environment under the free-energy principle for biological systems. Biological self-organization amounts to the minimization of surprise over time. We posit that any self-organizing system must embody a generative model whose predictions ensure that (expected) free energy is minimized through action. Plants respond in a fast, and yet coordinated manner, to environmental contingencies. They pro-actively sample their local environment to elicit information with an adaptive value. Our main thesis is that plant behaviour takes place by way of a process (active inference) that predicts the environmental sources of sensory stimulation. This principle, we argue, endows plants with a form of perception that underwrites purposeful, anticipatory behaviour. The aim of the article is to assess the prospects of a radical predictive processing story that would follow naturally from the free-energy principle for biological systems; an approach that may ultimately bear upon our understanding of life and cognition more broadly. PMID:28637913

  7. MANUAL: BIOVENTING PRINCIPLES AND PRACTICE VOLUME I. BIOVENTING PRINCIPLES

    EPA Science Inventory

    Bioventing is the process of aerating soils to stimulate in situ biological activity and promote bioremediation. Bioventing typically is applied in situ to the vadose zone and is applicable to any chemical that can be aerobically biodegraded but to date has primarily been impleme...

  8. Experimental Edema Disease of Swine (E. Coli ENTEROTOXEMIA) I. Detection and Preparation of an Active Principle

    PubMed Central

    Clugston, R. E.; Nielsen, N. O.

    1974-01-01

    Freeze-thaw lysates prepared from strains of Escherichia coli belonging to serogroups O138, O139, and O141 contained a principle (edema disease principle) which induced edema disease in swine. All freeze-thaw lysates contained endotoxic activity that tended to obscure the edema disease syndrome and methods were developed to reduce such activity. Freeze-thaw lysates prepared from E. coli O139 induced the most characteristic edema disease syndrome. Partially purified edema disease principle prepared from O139 freeze-thaw lysates by sequential precipitation with ammonium sulphate and streptomycin sulphate had increased specific activity with markedly reduced endotoxic activity. This material was insoluble at acidic pH but readily soluble at alkaline pH. The effective molecular weight of edema disease principle, based on retention and filtration properties of diaflo membranes, appeared to be greater than 50,000 and less than 100,000. The biological activity of edema disease principle was thermolabile. Sodium deoxycholate treatment of edema disease principle further reduced endotoxic activity. A thermolabile, ammonium sulphate precipitable material was prepared from E. coli O139 that induced a predictable syndrome which resembled edema disease clinically and pathologically following intravenous inoculation in pigs. PMID:4272954

  9. Ketosteroid Standardized Cissus quadrangularis L. Extract and its Anabolic Activity: Time to Look Beyond Ketosteroid?

    PubMed

    Jadhav, Atul N; Rafiq, Mohammed; Devanathan, Rajendran; Azeemuddin, Mohammed; Anturlikar, Suryakanth D; Ahmed, Akhil; Sundaram, Ramchandran; Babu, U V; Paramesh, Rangesh

    2016-05-01

    Cissus quadrangularis (CQ) L. reported to contain 3-ketosteroids and have bone health benefits. This study aimed at establishing the relationship between the ketosteroid content and anabolic as well as bone health-promoting activities of various Cissus extracts in well-established orchidectomized (ORX) rat model. Supercritical carbon dioxide, ethyl acetate, and aqueous extracts (AE) of CQ L. were prepared and standardized for ketosteroid content by two methods used in commerce. Moreover, ketosteroid standardized extracts of this plant were evaluated for anabolic activity in rats in well-established ORX rat model. The increase in the absolute weight was appreciable in the CQ-AE treated group. Similarly, with respect to bone parameters, a similar trend was seen. The mean bone density, strength, and calcium content were found to be highest in the group treated with CQ-AE compared to groups treated with other extracts. This study reveals for the first time that 3-ketosteroids are not linked to the beneficial activities on bone and highlights the need for extensive characterization of biological active principles from CQ L. In light of the above estimation studies, we believe that current standardization of Cissus extraction "3-ketosteroids" is incorrect. We also did not find any report suggesting the presence of androgenic steroids in this plant and hence the characterization based on "3-ketosteroids" is scientifically incorrect. This study highlights the insufficient understanding of biological active principles from CQ L. and underlines the need for extensive bioactivity guided studies. Cissus quadrangularis (CQ) L. reported to contain 3.ketosteroids and have bone health benefitsWe did not find correlation between ketosteroid content obtained by conventional methods and its biological effectStudies indicate that claims of ketosteroid content need not necessarily correlate to biological effects and hence warrants extensive phytochemical characterization of biological active principles from CQ L. Abbreviations used: CQ: Cissus quadrangularis, ORX: Orchidectomized, AE: Aqueous extract, EE: Ethyl acetate extract, SFE: Supercritical fluid extract.

  10. THE USE OF STRUCTURE-ACTIVITY RELATIONSHIPS IN INTEGRATING THE CHEMISTRY AND TOXICOLOGY OF ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Structure activity relationships (SARs) are based on the principle that structurally similar chemicals should have similar biological activity. SARs relate specifically-defined toxicological activity of chemicals to their molecular structure and physico-chemical properties. To de...

  11. Hydrocarbon-Stapled Peptides: Principles, Practice, and Progress

    PubMed Central

    2015-01-01

    Protein structure underlies essential biological processes and provides a blueprint for molecular mimicry that drives drug discovery. Although small molecules represent the lion’s share of agents that target proteins for therapeutic benefit, there remains no substitute for the natural properties of proteins and their peptide subunits in the majority of biological contexts. The peptide α-helix represents a common structural motif that mediates communication between signaling proteins. Because peptides can lose their shape when taken out of context, developing chemical interventions to stabilize their bioactive structure remains an active area of research. The all-hydrocarbon staple has emerged as one such solution, conferring α-helical structure, protease resistance, cellular penetrance, and biological activity upon successful incorporation of a series of design and application principles. Here, we describe our more than decade-long experience in developing stapled peptides as biomedical research tools and prototype therapeutics, highlighting lessons learned, pitfalls to avoid, and keys to success. PMID:24601557

  12. Biosafety Manual

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    King, Bruce W.

    2010-05-18

    Work with or potential exposure to biological materials in the course of performing research or other work activities at Lawrence Berkeley National Laboratory (LBNL) must be conducted in a safe, ethical, environmentally sound, and compliant manner. Work must be conducted in accordance with established biosafety standards, the principles and functions of Integrated Safety Management (ISM), this Biosafety Manual, Chapter 26 (Biosafety) of the Health and Safety Manual (PUB-3000), and applicable standards and LBNL policies. The purpose of the Biosafety Program is to protect workers, the public, agriculture, and the environment from exposure to biological agents or materials that may causemore » disease or other detrimental effects in humans, animals, or plants. This manual provides workers; line management; Environment, Health, and Safety (EH&S) Division staff; Institutional Biosafety Committee (IBC) members; and others with a comprehensive overview of biosafety principles, requirements from biosafety standards, and measures needed to control biological risks in work activities and facilities at LBNL.« less

  13. Recent trends and important developments in propolis research

    PubMed Central

    2005-01-01

    The newest developments in propolis pharmacological research are summarized. The problem regarding biological studies, caused by the chemical variability of propolis, is discussed. The most important trends and developments in recent propolis research are outlined: biological studies performed with chemically characterized samples, bioassay-guided studies of active principles and comparative biological studies of propolis of different origin and chemical composition. These types of studies are extremely valuable with respect to propolis standardization and practical applications in therapy. They will allow scientists to connect a particular chemical propolis type to a specific type of biological activity and formulate recommendations for practitioners. PMID:15841275

  14. Cross-hierarchy systems principles.

    PubMed

    Goentoro, Lea

    2017-02-01

    One driving motivation of systems biology is the search for general principles that govern the design of biological systems. But questions often arise as to what kind of general principles biology could have. Concepts from engineering such as robustness and modularity are indeed becoming a regular way of describing biological systems. Another source of potential general principles is the emerging similarities found in processes across biological hierarchies. In this piece, I describe several emerging cross-hierarchy similarities. Identification of more cross-hierarchy principles, and understanding the implications these convergence have on the construction of biological systems, I believe, present exciting challenges for systems biology in the decades to come.

  15. 76 FR 4360 - Guidance for Industry on Process Validation: General Principles and Practices; Availability

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ... elements of process validation for the manufacture of human and animal drug and biological products... process validation for the manufacture of human and animal drug and biological products, including APIs. This guidance describes process validation activities in three stages: In Stage 1, Process Design, the...

  16. Biological Awareness: Statements for Self-Discovery.

    ERIC Educational Resources Information Center

    Edington, D.W.; Cunningham, Lee

    This guide to biological awareness through guided self-discovery is based on 51 single focus statements concerning the human body. For each statement there are explanations of the underlying physiological principles and suggested activities and discussion ideas to encourage understanding of the statement in terms of the human body's functions,…

  17. Milkweed Seed Dispersal: A Means for Integrating Biology and Physics.

    ERIC Educational Resources Information Center

    Bisbee, Gregory D.; Kaiser, Cheryl A.

    1997-01-01

    Describes an activity that integrates biology and physics concepts by experimenting with the seed dispersal of common milkweed or similar wind-dispersed seeds. Student teams collect seeds and measure several parameters, review principles of trajectory motion, perform experiments, and graph data. Students examine the ideas of…

  18. On the search for design principles in biological systems.

    PubMed

    Poyatos, Juan F

    2012-01-01

    The search for basic concepts and underlying principles was at the core of the systems approach to science and technology. This approach was somehow abandoned in mainstream biology after its initial proposal, due to the rise and success of molecular biology. This situation has changed. The accumulated knowledge of decades of molecular studies in combination with new technological advances, while further highlighting the intricacies of natural systems, is also bringing back the quest-for-principles research program. Here, I present two lessons that I derived from my own quest: the importance of studying biological information processing to identify common principles in seemingly unrelated contexts and the adequacy of using known design principles at one level of biological organization as a valuable tool to help recognizing principles at an alternative one. These and additional lessons should contribute to the ultimate goal of establishing principles able to integrate the many scales of biological complexity.

  19. A Beach in Your Classroom.

    ERIC Educational Resources Information Center

    Conn, Kathleen

    2001-01-01

    Introduces an integrated science activity in which students learn about the principles of superposition, biostratigraphy, and correlation and study the single-celled microorganism foraminifera to learn about marine biology. (YDS)

  20. The impact of whole-plant instruction of preservice teachers' understanding of plant science principles

    NASA Astrophysics Data System (ADS)

    Hypolite, Christine Collins

    The purpose of this research was to determine how an inquiry-based, whole-plant instructional strategy would affect preservice elementary teachers' understanding of plant science principles. This study probed: what preservice teachers know about plant biology concepts before and after instruction, their views of the interrelatedness of plant parts and the environment, how growing a plant affects preservice teachers' understanding, and which types of activity-rich plant themes studies, if any, affect preservice elementary teachers' understandings. The participants in the study were enrolled in two elementary science methods class sections at a state university. Each group was administered a preinstructional test at the beginning of the study. The treatment group participated in inquiry-based activities related to the Principles of Plant Biology (American Society of Plant Biologists, 2001), while the comparison group studied those same concepts through traditional instructional methods. A focus group was formed from the treatment group to participate in co-concept mapping sessions. The participants' understandings were assessed through artifacts from activities, a comparison of pre- and postinstructional tests, and the concept maps generated by the focus group. Results of the research indicated that the whole-plant, inquiry-based instructional strategy can be applied to teach preservice elementary teachers plant biology while modeling the human constructivist approach. The results further indicated that this approach enhanced their understanding of plant science content knowledge, as well as pedagogical knowledge. The results also showed that a whole-plant approach to teaching plant science concepts is an instructional strategy that is feasible for the elementary school. The theoretical framework for this study was Human Constructivist learning theory (Mintzes & Wandersee, 1998). The content knowledge and instructional strategy was informed by the Principles of Plant Biology (American Society of Plant Biologists, 2001) and Botany for the Next Millennium (Botanical Society of America, 1995). As a result of this study, a better understanding of the factors that influence preservice elementary teachers' knowledge of plant science principles may benefit elementary science educator in preparing teachers that are "highly qualified."

  1. Novel active principles from spider venom.

    PubMed

    Vassilevski, Alexander A; Grishin, Eugene V

    2011-12-01

    Spiders are one of the most intriguing groups of venomous animals. Substances found in their venom vary from simple inorganic compounds to large multi-domain proteins. In this article, we review some of the latest work presenting active principles that add to the known spider toxin universe. Two aspects of novelty are addressed in particular, structural (novel types of molecules in terms of structure) and functional (novel types of biological targets hit by substances from spider venom and novel mechanisms of action).

  2. Synthesis of analogues of gingerol and shogaol, the active pungent principles from the rhizomes of Zingiber officinale and evaluation of their anti-platelet aggregation effects.

    PubMed

    Shih, Hung-Cheng; Chern, Ching-Yuh; Kuo, Ping-Chung; Wu, You-Cheng; Chan, Yu-Yi; Liao, Yu-Ren; Teng, Che-Ming; Wu, Tian-Shung

    2014-03-04

    The present study was aimed at discovering novel biologically active compounds based on the skeletons of gingerol and shogaol, the pungent principles from the rhizomes of Zingiber officinale. Therefore, eight groups of analogues were synthesized and examined for their inhibitory activities of platelet aggregation induced by arachidonic acid, collagen, platelet activating factor, and thrombin. Among the tested compounds, [6]-paradol (5b) exhibited the most significant anti-platelet aggregation activity. It was the most potent candidate, which could be used in further investigation to explore new drug leads.

  3. Synthesis of Analogues of Gingerol and Shogaol, the Active Pungent Principles from the Rhizomes of Zingiber officinale and Evaluation of Their Anti-Platelet Aggregation Effects

    PubMed Central

    Shih, Hung-Cheng; Chern, Ching-Yuh; Kuo, Ping-Chung; Wu, You-Cheng; Chan, Yu-Yi; Liao, Yu-Ren; Teng, Che-Ming; Wu, Tian-Shung

    2014-01-01

    The present study was aimed at discovering novel biologically active compounds based on the skeletons of gingerol and shogaol, the pungent principles from the rhizomes of Zingiber officinale. Therefore, eight groups of analogues were synthesized and examined for their inhibitory activities of platelet aggregation induced by arachidonic acid, collagen, platelet activating factor, and thrombin. Among the tested compounds, [6]-paradol (5b) exhibited the most significant anti-platelet aggregation activity. It was the most potent candidate, which could be used in further investigation to explore new drug leads. PMID:24599082

  4. Mosaic, self-similarity logic, and biological attraction principles: three explanatory instruments in biology.

    PubMed

    Agnati, Luigi F; Baluska, Frantisek; Barlow, Peter W; Guidolin, Diego

    2009-11-01

    From a structural standpoint, living organisms are organized like a nest of Russian matryoshka dolls, in which structures are buried within one another. From a temporal point of view, this type of organization is the result of a history comprised of a set of time backcloths which have accompanied the passage of living matter from its origins up to the present day. The aim of the present paper is to indicate a possible course of this 'passage through time, and suggest how today's complexity has been reached by living organisms. This investigation will employ three conceptual tools, namely the Mosaic, Self-Similarity Logic, and the Biological Attraction principles. Self-Similarity Logic indicates the self-consistency by which elements of a living system interact, irrespective of the spatiotemporal level under consideration. The term Mosaic indicates how, from the same set of elements assembled according to different patterns, it is possible to arrive at completely different constructions: hence, each system becomes endowed with different emergent properties. The Biological Attraction principle states that there is an inherent drive for association and merging of compatible elements at all levels of biological complexity. By analogy with the gravitation law in physics, biological attraction is based on the evidence that each living organism creates an attractive field around itself. This field acts as a sphere of influence that actively attracts similar fields of other biological systems, thereby modifying salient features of the interacting organisms. Three specific organizational levels of living matter, namely the molecular, cellular, and supracellular levels, have been considered in order to analyse and illustrate the interpretative as well as the predictive roles of each of these three explanatory principles.

  5. Fluorescent-protein-based probes: general principles and practices.

    PubMed

    Ai, Hui-Wang

    2015-01-01

    An important application of fluorescent proteins is to derive genetically encoded fluorescent probes that can actively respond to cellular dynamics such as pH change, redox signaling, calcium oscillation, enzyme activities, and membrane potential. Despite the large diverse group of fluorescent-protein-based probes, a few basic principles have been established and are shared by most of these probes. In this article, the focus is on these general principles and strategies that guide the development of fluorescent-protein-based probes. A few examples are provided in each category to illustrate the corresponding principles. Since these principles are quite straightforward, others may adapt them to create fluorescent probes for their own interest. Hopefully, the development of the ever-growing family of fluorescent-protein-based probes will no longer be limited to a small number of laboratories specialized in senor development, leading to the situation that biological studies will be bettered assisted by genetically encoded sensors.

  6. Theoretical principles for biology: Variation.

    PubMed

    Montévil, Maël; Mossio, Matteo; Pocheville, Arnaud; Longo, Giuseppe

    2016-10-01

    Darwin introduced the concept that random variation generates new living forms. In this paper, we elaborate on Darwin's notion of random variation to propose that biological variation should be given the status of a fundamental theoretical principle in biology. We state that biological objects such as organisms are specific objects. Specific objects are special in that they are qualitatively different from each other. They can undergo unpredictable qualitative changes, some of which are not defined before they happen. We express the principle of variation in terms of symmetry changes, where symmetries underlie the theoretical determination of the object. We contrast the biological situation with the physical situation, where objects are generic (that is, different objects can be assumed to be identical) and evolve in well-defined state spaces. We derive several implications of the principle of variation, in particular, biological objects show randomness, historicity and contextuality. We elaborate on the articulation between this principle and the two other principles proposed in this special issue: the principle of default state and the principle of organization. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. The Use of Radioactivation Analysis in Biology; APPLICAZIONI DELL'ANALISI PER RADIOATTIVAZIONE ALLA BIOLOGIA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Merlini, M.

    1962-01-01

    The principles of activation analysis and the methods of detection and measurement of radioactivity from neutron irradiated samples are described. The application of this method in different fields is mentioned. An example of the use of activation analysis in biology is given; and the results of a study on the manganese content in different parts of a lamellibranch, Unio mancus elongatus (Pfeiffer) of Lago Maggiore, are presented and discussed. (auth)

  8. Protein Multifunctionality: Principles and Mechanisms

    PubMed Central

    Zaretsky, Joseph Z.; Wreschner, Daniel H.

    2008-01-01

    In the review, the nature of protein multifunctionality is analyzed. In the first part of the review the principles of structural/functional organization of protein are discussed. In the second part, the main mechanisms involved in development of multiple functions on a single gene product(s) are analyzed. The last part represents a number of examples showing that multifunctionality is a basic feature of biologically active proteins. PMID:21566747

  9. Modelling of pathologies of the nervous system by the example of computational and electronic models of elementary nervous systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shumilov, V. N., E-mail: vnshumilov@rambler.ru; Syryamkin, V. I., E-mail: maximus70sir@gmail.com; Syryamkin, M. V., E-mail: maximus70sir@gmail.com

    The paper puts forward principles of action of devices operating similarly to the nervous system and the brain of biological systems. We propose an alternative method of studying diseases of the nervous system, which may significantly influence prevention, medical treatment, or at least retardation of development of these diseases. This alternative is to use computational and electronic models of the nervous system. Within this approach, we represent the brain in the form of a huge electrical circuit composed of active units, namely, neuron-like units and connections between them. As a result, we created computational and electronic models of elementary nervousmore » systems, which are based on the principles of functioning of biological nervous systems that we have put forward. Our models demonstrate reactions to external stimuli and their change similarly to the behavior of simplest biological organisms. The models possess the ability of self-training and retraining in real time without human intervention and switching operation/training modes. In our models, training and memorization take place constantly under the influence of stimuli on the organism. Training is without any interruption and switching operation modes. Training and formation of new reflexes occur by means of formation of new connections between excited neurons, between which formation of connections is physically possible. Connections are formed without external influence. They are formed under the influence of local causes. Connections are formed between outputs and inputs of two neurons, when the difference between output and input potentials of excited neurons exceeds a value sufficient to form a new connection. On these grounds, we suggest that the proposed principles truly reflect mechanisms of functioning of biological nervous systems and the brain. In order to confirm the correspondence of the proposed principles to biological nature, we carry out experiments for the study of processes of formation of connections between neurons in simplest biological objects. Based on the correspondence of function of the created models to function of biological nervous systems we suggest the use of computational and electronic models of the brain for the study of its function under normal and pathological conditions, because operating principles of the models are built on principles imitating the function of biological nervous systems and the brain.« less

  10. Modelling of pathologies of the nervous system by the example of computational and electronic models of elementary nervous systems

    NASA Astrophysics Data System (ADS)

    Shumilov, V. N.; Syryamkin, V. I.; Syryamkin, M. V.

    2015-11-01

    The paper puts forward principles of action of devices operating similarly to the nervous system and the brain of biological systems. We propose an alternative method of studying diseases of the nervous system, which may significantly influence prevention, medical treatment, or at least retardation of development of these diseases. This alternative is to use computational and electronic models of the nervous system. Within this approach, we represent the brain in the form of a huge electrical circuit composed of active units, namely, neuron-like units and connections between them. As a result, we created computational and electronic models of elementary nervous systems, which are based on the principles of functioning of biological nervous systems that we have put forward. Our models demonstrate reactions to external stimuli and their change similarly to the behavior of simplest biological organisms. The models possess the ability of self-training and retraining in real time without human intervention and switching operation/training modes. In our models, training and memorization take place constantly under the influence of stimuli on the organism. Training is without any interruption and switching operation modes. Training and formation of new reflexes occur by means of formation of new connections between excited neurons, between which formation of connections is physically possible. Connections are formed without external influence. They are formed under the influence of local causes. Connections are formed between outputs and inputs of two neurons, when the difference between output and input potentials of excited neurons exceeds a value sufficient to form a new connection. On these grounds, we suggest that the proposed principles truly reflect mechanisms of functioning of biological nervous systems and the brain. In order to confirm the correspondence of the proposed principles to biological nature, we carry out experiments for the study of processes of formation of connections between neurons in simplest biological objects. Based on the correspondence of function of the created models to function of biological nervous systems we suggest the use of computational and electronic models of the brain for the study of its function under normal and pathological conditions, because operating principles of the models are built on principles imitating the function of biological nervous systems and the brain.

  11. Physiology of Plants, Science (Experimental): 5315.41.

    ERIC Educational Resources Information Center

    Gunn, William C.

    This unit of instruction deals with the physiological activities of plants. Attention is focused on the principles which underlie the activities of the typical green land plant. Emphasis is placed on biological processes such as photosynthesis, water transport, light responses, mineral nutrition, reproduction, and growth. The prerequisite for…

  12. Quantum Mechanics predicts evolutionary biology.

    PubMed

    Torday, J S

    2018-07-01

    Nowhere are the shortcomings of conventional descriptive biology more evident than in the literature on Quantum Biology. In the on-going effort to apply Quantum Mechanics to evolutionary biology, merging Quantum Mechanics with the fundamentals of evolution as the First Principles of Physiology-namely negentropy, chemiosmosis and homeostasis-offers an authentic opportunity to understand how and why physics constitutes the basic principles of biology. Negentropy and chemiosmosis confer determinism on the unicell, whereas homeostasis constitutes Free Will because it offers a probabilistic range of physiologic set points. Similarly, on this basis several principles of Quantum Mechanics also apply directly to biology. The Pauli Exclusion Principle is both deterministic and probabilistic, whereas non-localization and the Heisenberg Uncertainty Principle are both probabilistic, providing the long-sought after ontologic and causal continuum from physics to biology and evolution as the holistic integration recognized as consciousness for the first time. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Why do we need theories?

    PubMed Central

    Longo, Giuseppe; Soto, Ana M.

    2017-01-01

    Theories organize knowledge and construct objectivity by framing observations and experiments. The elaboration of theoretical principles is examined in the light of the rich interactions between physics and mathematics. These two disciplines share common principles of construction of concepts and of the proper objects of inquiry. Theory construction in physics relies on mathematical symmetries that preserve the key invariants observed and proposed by such theory; these invariants buttress the idea that the objects of physics are generic and thus interchangeable and they move along specific trajectories which are uniquely determined, in classical and relativistic physics. In contrast to physics, biology is a historical science that centers on the changes that organisms experience while undergoing ontogenesis and phylogenesis. Biological objects, namely organisms, are not generic but specific; they are individuals. The incessant changes they undergo represent the breaking of symmetries, and thus the opposite of symmetry conservation, a central component of physical theories. This instability corresponds to the changes of the environment and the phenotypes. Inspired by Galileo’s principle of inertia, the “default state” of inert matter, we propose a “default state” for biological dynamics following Darwin’s first principle, “descent with modification” that we transform into “proliferation with variation and motility” as a property that spans life, including cells in an organism. These dissimilarities between theories of the inert and of biology also apply to causality: biological causality is to be understood in relation to the distinctive role that constraints assume in this discipline. Consequently, the notion of cause will be reframed in a context where constraints to activity are seen as the core component of biological analyses. Finally, we assert that the radical materiality of life rules out distinctions such as “software vs. hardware.” PMID:27390105

  14. Why do we need theories?

    PubMed

    Longo, Giuseppe; Soto, Ana M

    2016-10-01

    Theories organize knowledge and construct objectivity by framing observations and experiments. The elaboration of theoretical principles is examined in the light of the rich interactions between physics and mathematics. These two disciplines share common principles of construction of concepts and of the proper objects of inquiry. Theory construction in physics relies on mathematical symmetries that preserve the key invariants observed and proposed by such theory; these invariants buttress the idea that the objects of physics are generic and thus interchangeable and they move along specific trajectories which are uniquely determined, in classical and relativistic physics. In contrast to physics, biology is a historical science that centers on the changes that organisms experience while undergoing ontogenesis and phylogenesis. Biological objects, namely organisms, are not generic but specific; they are individuals. The incessant changes they undergo represent the breaking of symmetries, and thus the opposite of symmetry conservation, a central component of physical theories. This instability corresponds to the changes of the environment and the phenotypes. Inspired by Galileo's principle of inertia, the "default state" of inert matter, we propose a "default state" for biological dynamics following Darwin's first principle, "descent with modification" that we transform into "proliferation with variation and motility" as a property that spans life, including cells in an organism. These dissimilarities between theories of the inert and of biology also apply to causality: biological causality is to be understood in relation to the distinctive role that constraints assume in this discipline. Consequently, the notion of cause will be reframed in a context where constraints to activity are seen as the core component of biological analyses. Finally, we assert that the radical materiality of life rules out distinctions such as "software vs. hardware." Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Mosaic, Self-Similarity Logic, and Biological Attraction principles

    PubMed Central

    Baluška, František; Barlow, Peter W; Guidolin, Diego

    2009-01-01

    From a structural standpoint, living organisms are organized like a nest of Russian matryoshka dolls, in which structures are buried within one another. From a temporal point of view, this type of organization is the result of a history comprised of a set of time backcloths which have accompanied the passage of living matter from its origins up to the present day. The aim of the present paper is to indicate a possible course of this ‘passage through time, and suggest how today’s complexity has been reached by living organisms. This investigation will employ three conceptual tools, namely the Mosaic, Self-Similarity Logic, and the Biological Attraction principles. Self-Similarity Logic indicates the self-consistency by which elements of a living system interact, irrespective of the spatiotemporal level under consideration. The term Mosaic indicates how, from the same set of elements assembled according to different patterns, it is possible to arrive at completely different constructions: hence, each system becomes endowed with different emergent properties. The Biological Attraction principle states that there is an inherent drive for association and merging of compatible elements at all levels of biological complexity. By analogy with the gravitation law in physics, biological attraction is based on the evidence that each living organism creates an attractive field around itself. This field acts as a sphere of influence that actively attracts similar fields of other biological systems, thereby modifying salient features of the interacting organisms. Three specific organizational levels of living matter, namely the molecular, cellular, and supracellular levels, have been considered in order to analyse and illustrate the interpretative as well as the predictive roles of each of these three explanatory principles. PMID:20195461

  16. Using an FPLC to Promote Active Learning of the Principles of Protein Structure and Purification

    ERIC Educational Resources Information Center

    Robinson, Rebekah L.; Neely, Amy E.; Mojadedi, Wais; Threatt, Katie N.; Davis, Nicole Y.; Weiland, Mitch H.

    2017-01-01

    The concepts of protein purification are often taught in undergraduate biology and biochemistry lectures and reinforced during laboratory exercises; however, very few reported activities allow students to directly gain experience using modern protein purification instruments, such as Fast Protein Liquid Chromatography (FPLC). This laboratory…

  17. A Lab Exercise Explaining Hardy-Weinberg Equilibrium and Evolution Effectively.

    ERIC Educational Resources Information Center

    Winterer, Juliette

    2001-01-01

    Presents a set of six activities in population genetics for a college-level biology course that helps students understand the Hardy-Weinberg principle. Activities focus on characterizing a population, Hardy-Weinberg proportions, genetic drift, mutation and selection, population size and divergence, and secondary contact. The only materials…

  18. More examples of chimpanzees teaching.

    PubMed

    Scheel, Matthew H; Shaw, Heidi L; Gardner, R Allen

    2015-01-01

    Darwinism is a principle of biological continuity. This commentary argues against any claim of discontinuity between humans and other animals that must be based on absence of evidence. Instead, we offer additional examples of active teaching by chimpanzees.

  19. Bio-inspired active materials

    NASA Astrophysics Data System (ADS)

    Fratzl, Peter

    Biological tissues are naturally interactive and adaptive. In general, these features are due to the action of cells that provide sensing, actuation as well as tissue remodelling. There are also examples of materials synthesized by living organisms, such as plant seeds, which fulfil an active function without living cells working as mechanosensors and actuators. Thus the activity of these materials is based on physical principles alone, which provides inspiration for new concepts for artificial active materials. We will describe structural principles leading to movement in seed capsules triggered by ambient humidity and discuss the influence of internal architecture on the overall mechanical behaviour of materials, including actuation and motility. Several conceptual systems for actuating planar structures will be discussed.

  20. Synthetic Biology: Engineering Living Systems from Biophysical Principles.

    PubMed

    Bartley, Bryan A; Kim, Kyung; Medley, J Kyle; Sauro, Herbert M

    2017-03-28

    Synthetic biology was founded as a biophysical discipline that sought explanations for the origins of life from chemical and physical first principles. Modern synthetic biology has been reinvented as an engineering discipline to design new organisms as well as to better understand fundamental biological mechanisms. However, success is still largely limited to the laboratory and transformative applications of synthetic biology are still in their infancy. Here, we review six principles of living systems and how they compare and contrast with engineered systems. We cite specific examples from the synthetic biology literature that illustrate these principles and speculate on their implications for further study. To fully realize the promise of synthetic biology, we must be aware of life's unique properties. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  1. Effective Educational Videos: Principles and Guidelines for Maximizing Student Learning from Video Content.

    PubMed

    Brame, Cynthia J

    Educational videos have become an important part of higher education, providing an important content-delivery tool in many flipped, blended, and online classes. Effective use of video as an educational tool is enhanced when instructors consider three elements: how to manage cognitive load of the video; how to maximize student engagement with the video; and how to promote active learning from the video. This essay reviews literature relevant to each of these principles and suggests practical ways instructors can use these principles when using video as an educational tool. © 2016 C. J. Brame. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  2. Materials learning from life: concepts for active, adaptive and autonomous molecular systems.

    PubMed

    Merindol, Rémi; Walther, Andreas

    2017-09-18

    Bioinspired out-of-equilibrium systems will set the scene for the next generation of molecular materials with active, adaptive, autonomous, emergent and intelligent behavior. Indeed life provides the best demonstrations of complex and functional out-of-equilibrium systems: cells keep track of time, communicate, move, adapt, evolve and replicate continuously. Stirred by the understanding of biological principles, artificial out-of-equilibrium systems are emerging in many fields of soft matter science. Here we put in perspective the molecular mechanisms driving biological functions with the ones driving synthetic molecular systems. Focusing on principles that enable new levels of functionalities (temporal control, autonomous structures, motion and work generation, information processing) rather than on specific material classes, we outline key cross-disciplinary concepts that emerge in this challenging field. Ultimately, the goal is to inspire and support new generations of autonomous and adaptive molecular devices fueled by self-regulating chemistry.

  3. [Biological effects of resveratrol and other constituents of wine].

    PubMed

    Kollár, P; Hotolová, H

    2003-11-01

    In recent years many scientific papers have been published concerning the positive effects of wine and its active principles, the polyphenol resveratrol being the most widely discussed compound. The results of epidemiological and experimental studies in man, animals, and in vitro have shown that polyphenols contained in wine, tea, fruit, and vegetables exert a positive effect on both the progression and regression of atherosclerosis, possess an anticancerogenic action, and due to their antioxidative effects they act against other processes connected with the reactive forms of oxygen production and lipid peroxydation in the blood plasma and membranes. Experimental findings have shown that resveratrol protects the cardiovascular system, affects lipid metabolism, and inhibits low-density lipoproteins (LDL) oxidation and blood platelet aggregation. In addition, this natural product is able to inhibit the growth of some tumours and possesses antiinflammatory properties and a number of other biological effects. This report aims to describe and characterize in a summary the biological properties of the principal active principles of wine--flavonoids and polyphenols, with a detailed focus on resveratrol, which has been described as the most interesting agent.

  4. Antitumor properties and modulation of antioxidant enzymes' activity by Aloe vera leaf active principles isolated via supercritical carbon dioxide extraction.

    PubMed

    El-Shemy, H A; Aboul-Soud, M A M; Nassr-Allah, A A; Aboul-Enein, K M; Kabash, A; Yagi, A

    2010-01-01

    The aim of this study was to evaluate the potential anticancer properties and modulatory effect of selected Aloe vera (A. vera) active principles on antioxidant enzyme activities. Thus, three anthraquinones (Namely: aloesin, aloe-emodin and barbaloin) were extracted from A. vera leaves by supercritical fluid extraction and subsequently purified by high performance liquid chromatography. Additionally, the N-terminal octapeptide derived from verectin, a biologically active 14 kDa glycoprotein present in A. vera, was also tested. In vivo, active principles exhibited significant prolongation of the life span of tumor-transplanted animals in the following order: barbaloin> octapeptide> aloesin > aloe-emodin. A. vera active principles exhibited significant inhibition on Ehrlich ascite carcinoma cell (EACC) number, when compared to positive control group, in the following order: barbaloin> aloe-emodin > octapeptide > aloesin. Moreover, in trypan blue cell viability assay, active principles showed a significant concentration-dependent cytotoxicity against acute myeloid leukemia (AML) and acute lymphocytes leukemia (ALL) cancerous cells. Furthermore, in MTT cell viability test, aloe-emodin was found to be active against two human colon cancer cell lines (i.e. DLD-1 and HT2), with IC(50) values of 8.94 and 10.78 microM, respectively. Treatments of human AML leukemic cells with active principles (100 microg ml(-1)) resulted in varying intensities of internucleosomal DNA fragmentation, hallmark of cells undergoing apoptosis, in the following order: aloe-emodin> aloesin> barbaloin> octapeptide. Intererstingly, treatment of EACC tumors with active principles resulted in a significant elevation activity of key antioxidant enzymes (SOD, GST, tGPx, and LDH). Our data suggest that the tested A. vera compounds may exert their chemo-preventive effect through modulating antioxidant and detoxification enzyme activity levels, as they are one of the indicators of tumorigenesis. These findings are discussed in the light of the potential of A. vera plant extracts for developing efficient, specific and non-toxic anticancer drugs that are affordable for developing countries.

  5. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1985

    1985-01-01

    Presents 23 experiments, demonstrations, activities, and computer programs in biology, chemistry, and physics. Topics include lead in petrol, production of organic chemicals, reduction of water, enthalpy, X-ray diffraction model, nuclear magnetic resonance spectroscopy, computer simulation for additive mixing of colors, Archimedes Principle, and…

  6. Stochastic cycle selection in active flow networks

    NASA Astrophysics Data System (ADS)

    Woodhouse, Francis; Forrow, Aden; Fawcett, Joanna; Dunkel, Jorn

    2016-11-01

    Active biological flow networks pervade nature and span a wide range of scales, from arterial blood vessels and bronchial mucus transport in humans to bacterial flow through porous media or plasmodial shuttle streaming in slime molds. Despite their ubiquity, little is known about the self-organization principles that govern flow statistics in such non-equilibrium networks. By connecting concepts from lattice field theory, graph theory and transition rate theory, we show how topology controls dynamics in a generic model for actively driven flow on a network. Through theoretical and numerical analysis we identify symmetry-based rules to classify and predict the selection statistics of complex flow cycles from the network topology. Our conceptual framework is applicable to a broad class of biological and non-biological far-from-equilibrium networks, including actively controlled information flows, and establishes a new correspondence between active flow networks and generalized ice-type models.

  7. [The information principle in physiology: an analysis from the position of the general theory of functional systems].

    PubMed

    Sudakov, K V

    1995-01-01

    Information principle of the organism functional systems creation is formulated in the article. Transformation of organism biological needs on various levels into dominant motivation, behaviour and processes of basis needs satisfaction without loss in information sense is shown. Information role of emotions is analysed. On the base of experimental data is formulated concept of information environment of organism. Specially analysed the information basis of human psychological activity.

  8. Tracing organizing principles: learning from the history of systems biology.

    PubMed

    Green, Sara; Wolkenhauer, Olaf

    2013-01-01

    With the emergence of systems biology, the identification of organizing principles is being highlighted as a key research aim. Researchers attempt to "reverse engineer" the functional organization of biological systems using methodologies from mathematics, engineering and computer science while taking advantage of data produced by new experimental techniques. While systems biology is a relatively new approach, the quest for general principles of biological organization dates back to systems theoretic approaches in early and mid-twentieth century. The aim of this paper is to draw on this historical background in order to increase the understanding of the motivation behind the search for general principles and to clarify different epistemic aims within systems biology. We pinpoint key aspects of earlier approaches that also underlie the current practice. These are i) the focus on relational and system-level properties, ii) the inherent critique of reductionism and fragmentation of knowledge resulting from overspecialization, and iii) the insight that the ideal of formulating abstract organizing principles is complementary to, rather than conflicting with, the aim of formulating detailed explanations of biological mechanisms. We argue that looking back not only helps us understand the current practice but also points to possible future directions for systems biology.

  9. SOME CHEMICAL PROPERTIES UNDERLYING ARSENIC'S BIOLOGICAL ACTIVITY

    EPA Science Inventory

    ABSTRACT

    In this paper some of the chemical properties of arsenicals (atomic
    and molecular orbitals, electronegativity, valence state, changes between
    valence state, nucleophilicity, the hard/soft acid/base principle) that may
    account for some of the b...

  10. From flamingo dance to (desirable) drug discovery: a nature-inspired approach.

    PubMed

    Sánchez-Rodríguez, Aminael; Pérez-Castillo, Yunierkis; Schürer, Stephan C; Nicolotti, Orazio; Mangiatordi, Giuseppe Felice; Borges, Fernanda; Cordeiro, M Natalia D S; Tejera, Eduardo; Medina-Franco, José L; Cruz-Monteagudo, Maykel

    2017-10-01

    The therapeutic effects of drugs are well known to result from their interaction with multiple intracellular targets. Accordingly, the pharma industry is currently moving from a reductionist approach based on a 'one-target fixation' to a holistic multitarget approach. However, many drug discovery practices are still procedural abstractions resulting from the attempt to understand and address the action of biologically active compounds while preventing adverse effects. Here, we discuss how drug discovery can benefit from the principles of evolutionary biology and report two real-life case studies. We do so by focusing on the desirability principle, and its many features and applications, such as machine learning-based multicriteria virtual screening. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. INTEGRATING BIOLOGICAL PRINCIPLES WITH INSTRUCTION IN VOCATIONAL AGRICULTURE, A RESEARCH REPORT OF A GRADUATE STUDY. RESEARCH SERIES IN AGRICULTURAL EDUCATION.

    ERIC Educational Resources Information Center

    BENDER, RALPH E.; STARLING, JOHN T.

    TO DETERMINE THE FEASIBILITY OF INTEGRATING BIOLOGICAL PRINCIPLES WITH INSTRUCTION IN VOCATIONAL AGRICULTURE IN OHIO HIGH SCHOOLS, 15 PILOT SCHOOLS AND 8 CONTROL SCHOOLS WERE STUDIED. PRETESTS ADMINISTERED TO STUDENTS IN OCTOBER 1963 WERE AN AGRICULTURAL ACHIEVEMENT TEST, A BIOLOGICAL PRINCIPLES TEST, THE CALIFORNIA SHORT-FORM TEST OF MENTAL…

  12. The application of the multi-alternative approach in active neural network models

    NASA Astrophysics Data System (ADS)

    Podvalny, S.; Vasiljev, E.

    2017-02-01

    The article refers to the construction of intelligent systems based artificial neuron networks are used. We discuss the basic properties of the non-compliance of artificial neuron networks and their biological prototypes. It is shown here that the main reason for these discrepancies is the structural immutability of the neuron network models in the learning process, that is, their passivity. Based on the modern understanding of the biological nervous system as a structured ensemble of nerve cells, it is proposed to abandon the attempts to simulate its work at the level of the elementary neurons functioning processes and proceed to the reproduction of the information structure of data storage and processing on the basis of the general enough evolutionary principles of multialternativity, i.e. the multi-level structural model, diversity and modularity. The implementation method of these principles is offered, using the faceted memory organization in the neuron network with the rearranging active structure. An example of the implementation of the active facet-type neuron network in the intellectual decision-making system in the conditions of critical events development in the electrical distribution system.

  13. Selective functional activity measurement of a PEGylated protein with a modification-dependent activity assay.

    PubMed

    Weber, Alfred; Engelmaier, Andrea; Mohr, Gabriele; Haindl, Sonja; Schwarz, Hans Peter; Turecek, Peter L

    2017-01-05

    BAX 855 (ADYNOVATE) is a PEGylated recombinant factor VIII (rFVIII) that showed prolonged circulatory half-life compared to unmodified rFVIII in hemophilic patients. Here, the development and validation of a novel assay is described that selectively measures the activity of BAX 855 as cofactor for the serine protease factor IX, which actives factor X. This method type, termed modification-dependent activity assay, is based on PEG-specific capture of BAX 855 by an anti-PEG IgG preparation, followed by a chromogenic FVIII activity assay. The assay principle enabled sensitive measurement of the FVIII cofactor activity of BAX 855 down to the pM-range without interference by non-PEGylated FVIII. The selectivity of the capture step, shown by competition studies to primarily target the terminal methoxy group of PEG, also allowed assessment of the intactness of the attached PEG chains. Altogether, the modification-dependent activity not only enriches, but complements the group of methods to selectively, accurately, and precisely measure a PEGylated drug in complex biological matrices. In contrast to all other methods described so far, it allows measurement of the biological activity of the PEGylated protein. Data obtained demonstrate that this new method principle can be extended to protein modifications other than PEGylation and to a variety of functional activity assays. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Biological function in the twilight zone of sequence conservation.

    PubMed

    Ponting, Chris P

    2017-08-16

    Strong DNA conservation among divergent species is an indicator of enduring functionality. With weaker sequence conservation we enter a vast 'twilight zone' in which sequence subject to transient or lower constraint cannot be distinguished easily from neutrally evolving, non-functional sequence. Twilight zone functional sequence is illuminated instead by principles of selective constraint and positive selection using genomic data acquired from within a species' population. Application of these principles reveals that despite being biochemically active, most twilight zone sequence is not functional.

  15. Unidirectional rotary motion in a molecular system

    NASA Astrophysics Data System (ADS)

    Kelly, T. Ross; de Silva, Harshani; Silva, Richard A.

    1999-09-01

    The conversion of energy into controlled motion plays an important role in both man-made devices and biological systems. The principles of operation of conventional motors are well established, but the molecular processes used by `biological motors' such as muscle fibres, flagella and cilia to convert chemical energy into co-ordinated movement remain poorly understood. Although `brownian ratchets' are known to permit thermally activated motion in one direction only, the concept of channelling random thermal energy into controlled motion has not yet been extended to the molecular level. Here we describe a molecule that uses chemical energy to activate and bias a thermally induced isomerization reaction, and thereby achieve unidirectional intramolecular rotary motion. The motion consists of a 120° rotation around a single bond connecting a three-bladed subunit to the bulky remainder of the molecule, and unidirectional motion is achieved by reversibly introducing a tether between the two units to energetically favour one of the two possible rotation directions. Although our system does not achieve continuous and fast rotation, the design principles that we have used may prove relevant for a better understanding of biological and synthetic molecular motors producing unidirectional rotary motion.

  16. Unraveling helicase mechanisms one molecule at a time

    PubMed Central

    Rasnik, Ivan; Myong, Sua; Ha, Taekjip

    2006-01-01

    Recent years have seen an increasing number of biological applications of single molecule techniques, evolving from a proof of principle type to the more sophisticated studies. Here we compare the capabilities and limitations of different single molecule techniques in studying the activities of helicases. Helicases share a common catalytic activity but present a high variability in kinetic and phenomenological behavior, making their studies ideal in exemplifying the use of the new single molecule techniques to answer biological questions. Unexpected phenomena have also been observed from individual molecules suggesting extended or alternative functionality of helicases in vivo. PMID:16935883

  17. The role of mechanics in biological and bio-inspired systems.

    PubMed

    Egan, Paul; Sinko, Robert; LeDuc, Philip R; Keten, Sinan

    2015-07-06

    Natural systems frequently exploit intricate multiscale and multiphasic structures to achieve functionalities beyond those of man-made systems. Although understanding the chemical make-up of these systems is essential, the passive and active mechanics within biological systems are crucial when considering the many natural systems that achieve advanced properties, such as high strength-to-weight ratios and stimuli-responsive adaptability. Discovering how and why biological systems attain these desirable mechanical functionalities often reveals principles that inform new synthetic designs based on biological systems. Such approaches have traditionally found success in medical applications, and are now informing breakthroughs in diverse frontiers of science and engineering.

  18. Livestock Nutrition and Feeding. Student Manual. Second Edition.

    ERIC Educational Resources Information Center

    Ridenour, Harlan E.

    This manual is designed to help agricultural education students and teachers to apply scientific facts and principles to problem-solving procedures in determining nutritious and economical livestock feeding programs. The manual provides applied scientific activities in biological science and chemistry, mathematics, and communication skills. It…

  19. Gas-phase geometry optimization of biological molecules as a reasonable alternative to a continuum environment description: fact, myth, or fiction?

    PubMed

    Sousa, Sérgio Filipe; Fernandes, Pedro Alexandrino; Ramos, Maria João

    2009-12-31

    Gas-phase optimization of single biological molecules and of small active-site biological models has become a standard approach in first principles computational enzymology. The important role played by the surrounding environment (solvent, enzyme, both) is normally only accounted for through higher-level single point energy calculations performed using a polarizable continuum model (PCM) and an appropriate dielectric constant with the gas-phase-optimized geometries. In this study we analyze this widely used approximation, by comparing gas-phase-optimized geometries with geometries optimized with different PCM approaches (and considering different dielectric constants) for a representative data set of 20 very important biological molecules--the 20 natural amino acids. A total of 323 chemical bonds and 469 angles present in standard amino acid residues were evaluated. The results show that the use of gas-phase-optimized geometries can in fact be quite a reasonable alternative to the use of the more computationally intensive continuum optimizations, providing a good description of bond lengths and angles for typical biological molecules, even for charged amino acids, such as Asp, Glu, Lys, and Arg. This approximation is particularly successful if the protonation state of the biological molecule could be reasonably described in vacuum, a requirement that was already necessary in first principles computational enzymology.

  20. MACROMOLECULAR THERAPEUTICS

    PubMed Central

    Yang, Jiyuan; Kopeček, Jindřich

    2014-01-01

    This review covers water-soluble polymer-drug conjugates and macromolecules that possess biological activity without attached low molecular weight drugs. The main design principles of traditional and backbone degradable polymer-drug conjugates as well as the development of a new paradigm in nanomedicines – (low molecular weight) drug-free macromolecular therapeutics are discussed. To address the biological features of cancer, macromolecular therapeutics directed to stem/progenitor cells and the tumor microenvironment are deliberated. Finally, the future perspectives of the field are briefly debated. PMID:24747162

  1. Tramesan, a novel polysaccharide from Trametes versicolor. Structural characterization and biological effects

    PubMed Central

    Sveronis, Aris; Cescutti, Paola; Rizzo, Roberto

    2017-01-01

    Mushrooms represent a formidable source of bioactive compounds. Some of these may be considered as biological response modifiers; these include compounds with a specific biological function: antibiotics (e.g. plectasin), immune system stimulator (e,g, lentinan), antitumor agents (e.g. krestin, PSK) and hypolipidemic agents (e.g. lovastatin) inter alia. In this study, we focused on the Chinese medicinal mushroom “yun zhi”, Trametes versicolor, traditionally used for (cit.) “replenish essence and qi (vital energy)”. Previous studies indicated the potential activity of extracts from culture filtrate of asexual mycelia of T. versicolor in controlling the growth and secondary metabolism (e.g. mycotoxins) of plant pathogenic fungi. The quest of active principles produced by T. versicolor, allowed us characterising an exo-polysaccharide released in its culture filtrate and naming it Tramesan. Herein we evaluate the biological activity of Tramesan in different organisms: plants, mammals and plant pathogenic fungi. We suggest that the bioactivity of Tramesan relies mostly on its ability to act as pro antioxidant molecule regardless the biological system on which it was applied. PMID:28829786

  2. Tramesan, a novel polysaccharide from Trametes versicolor. Structural characterization and biological effects.

    PubMed

    Scarpari, Marzia; Reverberi, Massimo; Parroni, Alessia; Scala, Valeria; Fanelli, Corrado; Pietricola, Chiara; Zjalic, Slaven; Maresca, Vittoria; Tafuri, Agostino; Ricciardi, Maria R; Licchetta, Roberto; Mirabilii, Simone; Sveronis, Aris; Cescutti, Paola; Rizzo, Roberto

    2017-01-01

    Mushrooms represent a formidable source of bioactive compounds. Some of these may be considered as biological response modifiers; these include compounds with a specific biological function: antibiotics (e.g. plectasin), immune system stimulator (e,g, lentinan), antitumor agents (e.g. krestin, PSK) and hypolipidemic agents (e.g. lovastatin) inter alia. In this study, we focused on the Chinese medicinal mushroom "yun zhi", Trametes versicolor, traditionally used for (cit.) "replenish essence and qi (vital energy)". Previous studies indicated the potential activity of extracts from culture filtrate of asexual mycelia of T. versicolor in controlling the growth and secondary metabolism (e.g. mycotoxins) of plant pathogenic fungi. The quest of active principles produced by T. versicolor, allowed us characterising an exo-polysaccharide released in its culture filtrate and naming it Tramesan. Herein we evaluate the biological activity of Tramesan in different organisms: plants, mammals and plant pathogenic fungi. We suggest that the bioactivity of Tramesan relies mostly on its ability to act as pro antioxidant molecule regardless the biological system on which it was applied.

  3. Blackboard Electrophoresis: An Inexpensive Exercise on the Principles of DNA Restriction Analysis

    ERIC Educational Resources Information Center

    Costa, M. J.

    2007-01-01

    Undergraduates with little training on molecular biology may find the technical level of the typical introductory restriction laboratory too challenging and have problems with mastering the underlying concepts and processes. "Blackboard electrophoresis" is an active learning exercise, which focuses student attention on the sequences and principles…

  4. 76 FR 11075 - Schedules of Controlled Substances: Temporary Placement of Five Synthetic Cannabinoids Into...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-01

    ... of Abuse A ``cannabinoid'' is a class of chemical compounds in the marijuana plant that are... constituent of marijuana. ``Synthetic cannabinoids'' are a large family of chemically unrelated structures functionally (biologically) similar to THC, the active principle of marijuana. Two of the five synthetic...

  5. The Implementation of Research-based Learning on Biology Seminar Course in Biology Education Study Program of FKIP UMRAH

    NASA Astrophysics Data System (ADS)

    Amelia, T.

    2018-04-01

    Biology Seminar is a course in Biology Education Study Program of Faculty of Teacher Training and Education University of Maritim Raja Ali Haji (FKIP UMRAH) that requires students to have the ability to apply scientific attitudes, perform scientific writing and undertake scientific publications on a small scale. One of the learning strategies that can drive the achievement of learning outcomes in this course is Research-Based Learning. Research-Based Learning principles are considered in accordance with learning outcomes in Biology Seminar courses and generally in accordance with the purpose of higher education. On this basis, this article which is derived from a qualitative research aims at describing Research-based Learning on Biology Seminar course. Based on a case study research, it was known that Research-Based Learning on Biology Seminar courses is applied through: designing learning activities around contemporary research issues; teaching research methods, techniques and skills explicitly within program; drawing on personal research in designing and teaching courses; building small-scale research activities into undergraduate assignment; and infusing teaching with the values of researchers.

  6. Macromolecular therapeutics.

    PubMed

    Yang, Jiyuan; Kopeček, Jindřich

    2014-09-28

    This review covers water-soluble polymer-drug conjugates and macromolecules that possess biological activity without attached low molecular weight drugs. The main design principles of traditional and backbone degradable polymer-drug conjugates as well as the development of a new paradigm in nanomedicines - (low molecular weight) drug-free macromolecular therapeutics are discussed. To address the biological features of cancer, macromolecular therapeutics directed to stem/progenitor cells and the tumor microenvironment are deliberated. Finally, the future perspectives of the field are briefly debated. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Underlying Principles of Natural Selection in Network Evolution: Systems Biology Approach

    PubMed Central

    Chen, Bor-Sen; Wu, Wei-Sheng

    2007-01-01

    Systems biology is a rapidly expanding field that integrates diverse areas of science such as physics, engineering, computer science, mathematics, and biology toward the goal of elucidating the underlying principles of hierarchical metabolic and regulatory systems in the cell, and ultimately leading to predictive understanding of cellular response to perturbations. Because post-genomics research is taking place throughout the tree of life, comparative approaches offer a way for combining data from many organisms to shed light on the evolution and function of biological networks from the gene to the organismal level. Therefore, systems biology can build on decades of theoretical work in evolutionary biology, and at the same time evolutionary biology can use the systems biology approach to go in new uncharted directions. In this study, we present a review of how the post-genomics era is adopting comparative approaches and dynamic system methods to understand the underlying design principles of network evolution and to shape the nascent field of evolutionary systems biology. Finally, the application of evolutionary systems biology to robust biological network designs is also discussed from the synthetic biology perspective. PMID:19468310

  8. The Use of Group Activities in Introductory Biology Supports Learning Gains and Uniquely Benefits High-Achieving Students†

    PubMed Central

    Marbach-Ad, Gili; Rietschel, Carly H.; Saluja, Neeti; Carleton, Karen L.; Haag, Eric S.

    2016-01-01

    This study describes the implementation and effectiveness of small-group active engagement (GAE) exercises in an introductory biology course (BSCI207) taught in a large auditorium setting. BSCI207 (Principles of Biology III—Organismal Biology) is the third introductory core course for Biological Sciences majors. In fall 2014, the instructors redesigned one section to include GAE activities to supplement lecture content. One section (n = 198) employed three lectures per week. The other section (n = 136) replaced one lecture per week with a GAE class. We explored the benefits and challenges associated with implementing GAE exercises and their relative effectiveness for unique student groups (e.g., minority students, high- and low-grade point average [GPA] students). Our findings show that undergraduates in the GAE class exhibited greater improvement in learning outcomes than undergraduates in the traditional class. Findings also indicate that high-achieving students experienced the greatest benefit from GAE activities. Some at-risk student groups (e.g., two-year transfer students) showed comparably low learning gains in the course, despite the additional support that may have been afforded by active learning. Collectively, these findings provide valuable feedback that may assist other instructors who wish to revise their courses and recommendations for institutions regarding prerequisite coursework approval policies. PMID:28101262

  9. The Use of Group Activities in Introductory Biology Supports Learning Gains and Uniquely Benefits High-Achieving Students.

    PubMed

    Marbach-Ad, Gili; Rietschel, Carly H; Saluja, Neeti; Carleton, Karen L; Haag, Eric S

    2016-12-01

    This study describes the implementation and effectiveness of small-group active engagement (GAE) exercises in an introductory biology course (BSCI207) taught in a large auditorium setting. BSCI207 (Principles of Biology III-Organismal Biology) is the third introductory core course for Biological Sciences majors. In fall 2014, the instructors redesigned one section to include GAE activities to supplement lecture content. One section ( n = 198) employed three lectures per week. The other section ( n = 136) replaced one lecture per week with a GAE class. We explored the benefits and challenges associated with implementing GAE exercises and their relative effectiveness for unique student groups (e.g., minority students, high- and low-grade point average [GPA] students). Our findings show that undergraduates in the GAE class exhibited greater improvement in learning outcomes than undergraduates in the traditional class. Findings also indicate that high-achieving students experienced the greatest benefit from GAE activities. Some at-risk student groups (e.g., two-year transfer students) showed comparably low learning gains in the course, despite the additional support that may have been afforded by active learning. Collectively, these findings provide valuable feedback that may assist other instructors who wish to revise their courses and recommendations for institutions regarding prerequisite coursework approval policies.

  10. Deep hierarchies in the primate visual cortex: what can we learn for computer vision?

    PubMed

    Krüger, Norbert; Janssen, Peter; Kalkan, Sinan; Lappe, Markus; Leonardis, Ales; Piater, Justus; Rodríguez-Sánchez, Antonio J; Wiskott, Laurenz

    2013-08-01

    Computational modeling of the primate visual system yields insights of potential relevance to some of the challenges that computer vision is facing, such as object recognition and categorization, motion detection and activity recognition, or vision-based navigation and manipulation. This paper reviews some functional principles and structures that are generally thought to underlie the primate visual cortex, and attempts to extract biological principles that could further advance computer vision research. Organized for a computer vision audience, we present functional principles of the processing hierarchies present in the primate visual system considering recent discoveries in neurophysiology. The hierarchical processing in the primate visual system is characterized by a sequence of different levels of processing (on the order of 10) that constitute a deep hierarchy in contrast to the flat vision architectures predominantly used in today's mainstream computer vision. We hope that the functional description of the deep hierarchies realized in the primate visual system provides valuable insights for the design of computer vision algorithms, fostering increasingly productive interaction between biological and computer vision research.

  11. Effects of Humic Acids Isolated from Peat of Various Origin on in Vitro Production of Nitric Oxide: a Screening Study.

    PubMed

    Trofimova, E S; Zykova, M V; Ligacheva, A A; Sherstoboev, E Yu; Zhdanov, V V; Belousov, M V; Yusubov, M S; Krivoshchekov, S V; Danilets, M G; Dygai, A M

    2016-09-01

    A screening study of biological activity of native humic acids isolated from peat was performed; several physical and chemical parameters of their structures were studied by UV- and infrared spectroscopy. Spectroscopy yielded similar shape of light absorption curves of humic acids of different origin, which can reflect similarity of general structural principles of these substances. Alkaline humic acids have more developed system of polyconjugation, while molecular structures of pyrophosphate humic acids were characterized by higher aromaticity and condensation indexes. Biological activity of the studied humic acids was assessed by NO-stimulating capacity during their culturing with murine peritoneal macrophages in a wide concentration range. It was shown that due to dose-dependent enhancement of NO production humic acids can change the functional state of macrophages towards development of pro-inflammatory properties. These changes were associated with high activity of humic acids isolated by pyrophosphate extraction, which allows considering effects of isolation method on biological activity.

  12. Practices and exploration on competition of molecular biological detection technology among students in food quality and safety major.

    PubMed

    Chang, Yaning; Peng, Yuke; Li, Pengfei; Zhuang, Yingping

    2017-07-08

    With the increasing importance in the application of the molecular biological detection technology in the field of food safety, strengthening education in molecular biology experimental techniques is more necessary for the culture of the students in food quality and safety major. However, molecular biology experiments are not always in curricula of Food quality and safety Majors. This paper introduced a project "competition of molecular biological detection technology for food safety among undergraduate sophomore students in food quality and safety major", students participating in this project needed to learn the fundamental molecular biology experimental techniques such as the principles of molecular biology experiments and genome extraction, PCR and agarose gel electrophoresis analysis, and then design the experiments in groups to identify the meat species in pork and beef products using molecular biological methods. The students should complete the experimental report after basic experiments, write essays and make a presentation after the end of the designed experiments. This project aims to provide another way for food quality and safety majors to improve their knowledge of molecular biology, especially experimental technology, and enhances them to understand the scientific research activities as well as give them a chance to learn how to write a professional thesis. In addition, in line with the principle of an open laboratory, the project is also open to students in other majors in East China University of Science and Technology, in order to enhance students in other majors to understand the fields of molecular biology and food safety. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(4):343-350, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

  13. Toward a theory of organisms: Three founding principles in search of a useful integration

    PubMed Central

    SOTO, ANA M.; LONGO, GIUSEPPE; MIQUEL, PAUL-ANTOINE; MONTEVIL, MAËL; MOSSIO, MATTEO; PERRET, NICOLE; POCHEVILLE, ARNAUD; SONNENSCHEIN, CARLOS

    2016-01-01

    Organisms, be they uni- or multi-cellular, are agents capable of creating their own norms; they are continuously harmonizing their ability to create novelty and stability, that is, they combine plasticity with robustness. Here we articulate the three principles for a theory of organisms proposed in this issue, namely: the default state of proliferation with variation and motility, the principle of variation and the principle of organization. These principles profoundly change both biological observables and their determination with respect to the theoretical framework of physical theories. This radical change opens up the possibility of anchoring mathematical modeling in biologically proper principles. PMID:27498204

  14. Active matter at the interface between materials science and cell biology

    NASA Astrophysics Data System (ADS)

    Needleman, Daniel; Dogic, Zvonimir

    2017-09-01

    The remarkable processes that characterize living organisms, such as motility, self-healing and reproduction, are fuelled by a continuous injection of energy at the microscale. The field of active matter focuses on understanding how the collective behaviours of internally driven components can give rise to these biological phenomena, while also striving to produce synthetic materials composed of active energy-consuming components. The synergistic approach of studying active matter in both living cells and reconstituted systems assembled from biochemical building blocks has the potential to transform our understanding of both cell biology and materials science. This methodology can provide insight into the fundamental principles that govern the dynamical behaviours of self-organizing subcellular structures, and can lead to the design of artificial materials and machines that operate away from equilibrium and can thus attain life-like properties. In this Review, we focus on active materials made of cytoskeletal components, highlighting the role of active stresses and how they drive self-organization of both cellular structures and macroscale materials, which are machines powered by nanomachines.

  15. A Simple Classroom Teaching Technique to Help Students Understand Michaelis-Menten Kinetics

    ERIC Educational Resources Information Center

    Runge, Steven W.; Hill, Brent J. F.; Moran, William M.

    2006-01-01

    A new, simple classroom technique helps cell biology students understand principles of Michaelis-Menten enzyme kinetics. A student mimics the enzyme and the student's hand represents the enzyme's active site. The catalytic event is the transfer of marbles (substrate molecules) by hand from one plastic container to another. As predicted, increases…

  16. Building scientific confidence in metabolic similarity in read-across through the use of in vitro, in silico and analytical data

    EPA Science Inventory

    The underlying principle of read-across is that the biological activity of a chemical is inherent in its molecular structure. Analogues are typically identified by structural similarity then evaluated on the basis of their bioavailability, reactivity and metabolic similarity. Whi...

  17. Extreme Arthropods: Exploring Evolutionary Adaptations to Polar and Temperate Deserts

    ERIC Educational Resources Information Center

    Sandro, Luke; Constible, Juanita M.; Lee, Richard E., Jr.

    2007-01-01

    In this activity, Namib and Antarctic arthropods are used to illustrate several important biological principles. Among these are the key ideas that form follows function and that the environment drives evolution. In addition, students will discover that the climates of the Namib Desert and the Antarctic Peninsula are similar in several ways, and…

  18. 20180312 - Building scientific confidence in metabolic similarity in read-across through the use of in vitro, in silico and analytical data (SOT)

    EPA Science Inventory

    The underlying principle of read-across is that the biological activity of a chemical is inherent in its molecular structure. Analogues are typically identified by structural similarity then evaluated on the basis of their bioavailability, reactivity and metabolic similarity. Whi...

  19. [Benign bone tumors. General principles].

    PubMed

    Hillmann, A; Gösling, T

    2014-10-01

    Benign bone tumors and tumor-like lesions are much more frequent than malignant bone tumors among the total number of tumors of the skeleton. This article gives a presentation of the characteristics and treatment modalities of benign bone tumors. In this article in-house treatment principles are compared with those in the currently available literature. Benign bone tumors are frequently found incidentally; however, the term benign does not always signify that a purely observational role is needed. Benign bone tumors differ in their biological behavior and can be latent, active or aggressive which determines the treatment approach. Some benign bone tumors are just as aggressive locally as malignant tumors. The most important diagnostic feature is still conventional radiography and a thorough systematic analysis is necessary. Therapy options range from ignore, wait and see up to wide resection. In contrast to malignant tumors the radicalism of resection can be weighed against the accompanying local control and loss of function. The treatment of benign bone tumors depends on the histological type and the biological activity. Most benign bone tumors are diagnosed incidentally and do not necessitate any treatment.

  20. The Markov blankets of life: autonomy, active inference and the free energy principle

    PubMed Central

    Palacios, Ensor; Friston, Karl; Kiverstein, Julian

    2018-01-01

    This work addresses the autonomous organization of biological systems. It does so by considering the boundaries of biological systems, from individual cells to Home sapiens, in terms of the presence of Markov blankets under the active inference scheme—a corollary of the free energy principle. A Markov blanket defines the boundaries of a system in a statistical sense. Here we consider how a collective of Markov blankets can self-assemble into a global system that itself has a Markov blanket; thereby providing an illustration of how autonomous systems can be understood as having layers of nested and self-sustaining boundaries. This allows us to show that: (i) any living system is a Markov blanketed system and (ii) the boundaries of such systems need not be co-extensive with the biophysical boundaries of a living organism. In other words, autonomous systems are hierarchically composed of Markov blankets of Markov blankets—all the way down to individual cells, all the way up to you and me, and all the way out to include elements of the local environment. PMID:29343629

  1. Designing Networks that are Capable of Self-Healing and Adapting

    DTIC Science & Technology

    2017-04-01

    from statistical mechanics, combinatorics, boolean networks, and numerical simulations, and inspired by design principles from biological networks, we... principles for self-healing networks, and applications, and construct an all-possible-paths model for network adaptation. 2015-11-16 UNIT CONVERSION...combinatorics, boolean networks, and numerical simulations, and inspired by design principles from biological networks, we will undertake the fol

  2. To Fly or Not to Fly: Teaching Advanced Secondary School Students about Principles of Flight in Biological Systems

    ERIC Educational Resources Information Center

    Pietsch, Renée B.; Bohland, Cynthia L.; Schmale, David G., III.

    2015-01-01

    Biological flight mechanics is typically taught in graduate level college classes rather than in secondary school classes. We developed an interdisciplinary unit for advanced upper-level secondary school students (ages 15-18) to teach the principles of flight and applications to biological systems. This unit capitalised on the tremendous…

  3. Piquing Student Interest with Pharmacology: An Interdisciplinary Program Helps High School Students Learn Biology and Chemistry Principles

    ERIC Educational Resources Information Center

    Halpin, Myra J.; Hoeffler, Leanne; Schwartz-Bloom, Rochelle D.

    2005-01-01

    To help students learn science concepts, Pharmacology Education Partnership (PEP)--a science education program that incorporates relevant topics related to drugs and drug abuse into standard biology and chemistry curricula was developed. The interdisciplinary PEP curriculum provides six modules to teach biology and chemistry principles within the…

  4. Inhibitory effects of Aphanizomenon flos-aquae constituents on human UDP-glucose dehydrogenase activity.

    PubMed

    Scoglio, Stefano; Lo Curcio, Valeria; Catalani, Simona; Palma, Francesco; Battistelli, Serafina; Benedetti, Serena

    2016-12-01

    The purpose of this study was to investigate the in vitro inhibitory effects of the edible microalga Aphanizomenon flos-aquae (AFA) on human UDP-α-d-glucose 6-dehydrogenase (UGDH) activity, a cytosolic enzyme involved both in tumor progression and in phytochemical bioavailability. Both the hydrophilic and ethanolic AFA extracts as well as the constitutive active principles phycocyanin (PC), phycocyanobilin (PCB) and mycosporine-like amino acids (MAAs) were tested. Among AFA components, PCB presented the strongest inhibitory effect on UGDH activity, acting as a competitive inhibitor with respect to UDP-glucose and a non-competitive inhibitor with respect to NAD(+). In preliminary experiments, AFA PCB was also effective in reducing the colony formation capacity of PC-3 prostate cancer cells and FTC-133 thyroid cancer cells. Overall, these findings confirmed that AFA and its active principles are natural compounds with high biological activity. Further studies evaluating the effects of AFA PCB in reducing tumor cell growth and phytochemical glucuronidation are encouraged.

  5. Organizing principles as tools for bridging the gap between system theory and biological experimentation.

    PubMed

    Mekios, Constantinos

    2016-04-01

    Twentieth-century theoretical efforts towards the articulation of general system properties came short of having the significant impact on biological practice that their proponents envisioned. Although the latter did arrive at preliminary mathematical formulations of such properties, they had little success in showing how these could be productively incorporated into the research agenda of biologists. Consequently, the gap that kept system-theoretic principles cut-off from biological experimentation persisted. More recently, however, simple theoretical tools have proved readily applicable within the context of systems biology. In particular, examples reviewed in this paper suggest that rigorous mathematical expressions of design principles, imported primarily from engineering, could produce experimentally confirmable predictions of the regulatory properties of small biological networks. But this is not enough for contemporary systems biologists who adopt the holistic aspirations of early systemologists, seeking high-level organizing principles that could provide insights into problems of biological complexity at the whole-system level. While the presented evidence is not conclusive about whether this strategy could lead to the realization of the lofty goal of a comprehensive explanatory integration, it suggests that the ongoing quest for organizing principles is pragmatically advantageous for systems biologists. The formalisms postulated in the course of this process can serve as bridges between system-theoretic concepts and the results of molecular experimentation: they constitute theoretical tools for generalizing molecular data, thus producing increasingly accurate explanations of system-wide phenomena.

  6. The August Krogh principle applies to plants

    NASA Technical Reports Server (NTRS)

    Wayne, R.; Staves, M. P.

    1996-01-01

    The Krogh principle refers to the use of a large number of animals to study the large number of physiological problems, rather than limiting study to a particular organism for all problems. There may be organisms that are more suited to study of a particular problem than others. This same principle applies to plants. The authors are concerned with the recent trend in plant biology of using Arabidopsis thaliana as the "organism of choice." Arabidopsis is an excellent organism for molecular genetic research, but other plants are superior models for other research areas of plant biology. The authors present examples of the successful use of the Krogh principle in plant cell biology research, emphasizing the particular characteristics of the selected research organisms that make them the appropriate choice.

  7. Ecological principles, biodiversity, and the electric utility industry

    NASA Astrophysics Data System (ADS)

    Temple, Stanley A.

    1996-11-01

    The synthetic field of conservation biology uses principles derived from many different disciplines to address biodiversity issues. Many of these principles have come from ecology, and two simple ones that seem to relate to many issues involving the utility industry are: (1) “Everything is interconnected” (and should usually stay that way), and (2) “We can never do merely one thing.” The first principle can be applied to both the biotic and physical environments that are impacted by industrial activities. Habitat fragmentation and the loss of physical and biotic connectedness that results are frequently associated with transmission rights-of-way. These problems can be reduced—or even turned into conservation benefits—by careful planning and creative management. The second principle applies to the utility industry's programs to deal with carbon released by burning fossil fuels. Ecological knowledge can allow these programs to contribute to the preservation of biodiversity in addition to addressing a pollution problem. Without careful ecological analyses, industry could easily create new problems while implementing solutions to old ones.

  8. Stochastic cycle selection in active flow networks.

    PubMed

    Woodhouse, Francis G; Forrow, Aden; Fawcett, Joanna B; Dunkel, Jörn

    2016-07-19

    Active biological flow networks pervade nature and span a wide range of scales, from arterial blood vessels and bronchial mucus transport in humans to bacterial flow through porous media or plasmodial shuttle streaming in slime molds. Despite their ubiquity, little is known about the self-organization principles that govern flow statistics in such nonequilibrium networks. Here we connect concepts from lattice field theory, graph theory, and transition rate theory to understand how topology controls dynamics in a generic model for actively driven flow on a network. Our combined theoretical and numerical analysis identifies symmetry-based rules that make it possible to classify and predict the selection statistics of complex flow cycles from the network topology. The conceptual framework developed here is applicable to a broad class of biological and nonbiological far-from-equilibrium networks, including actively controlled information flows, and establishes a correspondence between active flow networks and generalized ice-type models.

  9. Stochastic cycle selection in active flow networks

    PubMed Central

    Woodhouse, Francis G.; Forrow, Aden; Fawcett, Joanna B.; Dunkel, Jörn

    2016-01-01

    Active biological flow networks pervade nature and span a wide range of scales, from arterial blood vessels and bronchial mucus transport in humans to bacterial flow through porous media or plasmodial shuttle streaming in slime molds. Despite their ubiquity, little is known about the self-organization principles that govern flow statistics in such nonequilibrium networks. Here we connect concepts from lattice field theory, graph theory, and transition rate theory to understand how topology controls dynamics in a generic model for actively driven flow on a network. Our combined theoretical and numerical analysis identifies symmetry-based rules that make it possible to classify and predict the selection statistics of complex flow cycles from the network topology. The conceptual framework developed here is applicable to a broad class of biological and nonbiological far-from-equilibrium networks, including actively controlled information flows, and establishes a correspondence between active flow networks and generalized ice-type models. PMID:27382186

  10. A comparison of biological and cultural evolution.

    PubMed

    Portin, Petter

    2015-03-01

    This review begins with a definition of biological evolution and a description of its general principles. This is followed by a presentation of the biological basis of culture, specifically the concept of social selection. Further, conditions for cultural evolution are proposed, including a suggestion for language being the cultural replicator corresponding to the concept of the gene in biological evolution. Principles of cultural evolution are put forward and compared to the principles of biological evolution. Special emphasis is laid on the principle of selection in cultural evolution, including presentation of the concept of cultural fitness. The importance of language as a necessary condition for cultural evolution is stressed. Subsequently, prime differences between biological and cultural evolution are presented, followed by a discussion on interaction of our genome and our culture. The review aims at contributing to the present discussion concerning the modern development of the general theory of evolution, for example by giving a tentative formulation of the necessary and sufficient conditions for cultural evolution, and proposing that human creativity and mind reading or theory of mind are motors specific for it. The paper ends with the notion of the still ongoing coevolution of genes and culture.

  11. Beyond the hydrophobic effect: Critical function of water at biological phase boundaries--A hypothesis.

    PubMed

    Damodaran, Srinivasan

    2015-07-01

    Many life-sustaining processes in living cells occur at the membrane-water interface. The pertinent questions that need to be asked are what is the evolutionary reason for biology to choose the membrane-water interface as the site for performing and/or controlling crucial biological reactions and what is the key physical principle that is singular to the membrane-water interface that biology exploits for regulating metabolic processes in cells? In this review, a hypothesis is developed, which espouses that cells control activities of membrane-bound enzymes and receptor activated processes via manipulating the thermodynamic activity of water at the membrane-water interfacial region. In support of this hypothesis, first we establish that the surface pressure of a lipid monolayer is a direct measure of a reduction in the thermodynamic activity of interfacial water. Second, we show that the surface pressure-dependent activation/inactivation of interfacial enzymes is fundamentally related to their dependence on interfacial water activity. We extend this argument to infer that cells might manipulate activities of membrane-associated biological processes via manipulating the activity of interfacial water via localized compression or expansion of the interface. In this paper, we critically analyze literature data on mechano-activation of large pore ion channels in Escherichia coli spheroplasts and G-proteins in reconstituted lipid vesicles, and show that these pressure-induced activation processes are fundamentally and quantitatively related to changes in the thermodynamic state of interfacial water, caused by mechanical stretching of the bilayer. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. How Scientists Use Critical-Thinking Skills: Isolating Both Total RNA and Protein Using the Same Small Organ

    ERIC Educational Resources Information Center

    Porta, Angela R.; Dhawan, Puneet

    2006-01-01

    Undergraduate biology programs are currently undergoing reform to involve students in biomedical research. Engaging students in more active, hands-on experiments allows students to discover scientific principles for themselves, and to develop techniques of critical thinking and problem solving. This models the world of real scientific research,…

  13. Feasibility Analysis of Incorporating In-Vitro Toxicokinetic Data as a Surrogate for In-Vivo Data for Read-across Predictions (ASCCT meeting)

    EPA Science Inventory

    The underlying principle of read-across is that biological activity is a function of physical and structural properties of chemicals. Analogs are typically identified on the basis of structural similarity and subsequently evaluated for their use in read-across on the basis of the...

  14. Quantitative structure-activity relationships (QSAR) of some 2,2-diphenyl propionate (DPP) derivatives of muscarinic antagonists

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gordon, R.K.; Breuer, E.; Padilla, F.N.

    1987-05-01

    QSAR between biological activities and molecular-chemical properties were investigated to aid in designing more effective and potent antimuscarinic pharmacophores. A molecular modeling program was used to calculate geometrical and topological values of a series of DPP pharmacophores. The newly synthesized pharmacophores were tested for their antagonist activities by: (1) inhibition of (N-methyl-/sup 3/H)scopolamine binding assay to the muscarinic receptors of N4TG1 neuroblastoma cells; (2) blocking of acetylcholine-induced contraction of guinea pig ileum; and (3) inhibition of carbachol-induced ..cap alpha..-amylase release from rat pancreas. The differences in the log of these biological activities were directly and significantly related to the distancesmore » between the carbonyl oxygen of the DPP and the quaternary nitrogen of the modified pharmacophores. The biological activities, while depending on each particular assay, varied between three and four logs of activity. The charge remained the same in all the pharmacophores. There were no QSAR correlations between molecular volume, molecular connectivity, or principle moments and their antagonistic activities, although multivariate QSAR was not employed. Thus, based on distance geometry, potent muscarinic pharmacophores can be predicted.« less

  15. Mechatronics design principles for biotechnology product development.

    PubMed

    Mandenius, Carl-Fredrik; Björkman, Mats

    2010-05-01

    Traditionally, biotechnology design has focused on the manufacture of chemicals and biologics. Still, a majority of biotechnology products that appear on the market today is the result of mechanical-electric (mechatronic) construction. For these, the biological components play decisive roles in the design solution; the biological entities are either integral parts of the design, or are transformed by the mechatronic system. This article explains how the development and production engineering design principles used for typical mechanical products can be adapted to the demands of biotechnology products, and how electronics, mechanics and biology can be integrated more successfully. We discuss three emerging areas of biotechnology in which mechatronic design principles can apply: stem cell manufacture, artificial organs, and bioreactors. Copyright 2010 Elsevier Ltd. All rights reserved.

  16. Bioinspired principles for large-scale networked sensor systems: an overview.

    PubMed

    Jacobsen, Rune Hylsberg; Zhang, Qi; Toftegaard, Thomas Skjødeberg

    2011-01-01

    Biology has often been used as a source of inspiration in computer science and engineering. Bioinspired principles have found their way into network node design and research due to the appealing analogies between biological systems and large networks of small sensors. This paper provides an overview of bioinspired principles and methods such as swarm intelligence, natural time synchronization, artificial immune system and intercellular information exchange applicable for sensor network design. Bioinspired principles and methods are discussed in the context of routing, clustering, time synchronization, optimal node deployment, localization and security and privacy.

  17. Soil Biological Activity Contributing to Phosphorus Availability in Vertisols under Long-Term Organic and Conventional Agricultural Management

    PubMed Central

    Bhat, Nisar A.; Riar, Amritbir; Ramesh, Aketi; Iqbal, Sanjeeda; Sharma, Mahaveer P.; Sharma, Sanjay K.; Bhullar, Gurbir S.

    2017-01-01

    Mobilization of unavailable phosphorus (P) to plant available P is a prerequisite to sustain crop productivity. Although most of the agricultural soils have sufficient amounts of phosphorus, low availability of native soil P remains a key limiting factor to increasing crop productivity. Solubilization and mineralization of applied and native P to plant available form is mediated through a number of biological and biochemical processes that are strongly influenced by soil carbon/organic matter, besides other biotic and abiotic factors. Soils rich in organic matter are expected to have higher P availability potentially due to higher biological activity. In conventional agricultural systems mineral fertilizers are used to supply P for plant growth, whereas organic systems largely rely on inputs of organic origin. The soils under organic management are supposed to be biologically more active and thus possess a higher capability to mobilize native or applied P. In this study we compared biological activity in soil of a long-term farming systems comparison field trial in vertisols under a subtropical (semi-arid) environment. Soil samples were collected from plots under 7 years of organic and conventional management at five different time points in soybean (Glycine max) -wheat (Triticum aestivum) crop sequence including the crop growth stages of reproductive significance. Upon analysis of various soil biological properties such as dehydrogenase, β-glucosidase, acid and alkaline phosphatase activities, microbial respiration, substrate induced respiration, soil microbial biomass carbon, organically managed soils were found to be biologically more active particularly at R2 stage in soybean and panicle initiation stage in wheat. We also determined the synergies between these biological parameters by using the methodology of principle component analysis. At all sampling points, P availability in organic and conventional systems was comparable. Our findings clearly indicate that owing to higher biological activity, organic systems possess equal capabilities of supplying P for crop growth as are conventional systems with inputs of mineral P fertilizers. PMID:28928758

  18. JPRS Report, China, Handbook of Military Knowledge for Commanders

    DTIC Science & Technology

    1988-03-07

    Chemical and Biological Weapons Chapter I Nuclear Weapons (178) A. Summary Statement on Nuclear Weapons (178) 1. Basic Principles of Nuclear...199) 1. Basic Principles of Protection Against Nuclear, Chemical and Biological Weapons* (199) 2. Maior Actions For Protection Against Nuclear...people’s bodies through the digestive tract. Skin contact. Biological warfare agents may enter the body directly through the skin , mucous membranes or

  19. Maximizing the Adjacent Possible in Automata Chemistries.

    PubMed

    Hickinbotham, Simon; Clark, Edward; Nellis, Adam; Stepney, Susan; Clarke, Tim; Young, Peter

    2016-01-01

    Automata chemistries are good vehicles for experimentation in open-ended evolution, but they are by necessity complex systems whose low-level properties require careful design. To aid the process of designing automata chemistries, we develop an abstract model that classifies the features of a chemistry from a physical (bottom up) perspective and from a biological (top down) perspective. There are two levels: things that can evolve, and things that cannot. We equate the evolving level with biology and the non-evolving level with physics. We design our initial organisms in the biology, so they can evolve. We design the physics to facilitate evolvable biologies. This architecture leads to a set of design principles that should be observed when creating an instantiation of the architecture. These principles are Everything Evolves, Everything's Soft, and Everything Dies. To evaluate these ideas, we present experiments in the recently developed Stringmol automata chemistry. We examine the properties of Stringmol with respect to the principles, and so demonstrate the usefulness of the principles in designing automata chemistries.

  20. Current advances in screening for bioactive components from medicinal plants by affinity ultrafiltration mass spectrometry.

    PubMed

    Chen, Guilin; Huang, Bill X; Guo, Mingquan

    2018-05-21

    Medicinal plants have played an important role in maintaining human health for thousands of years. However, the interactions between the active components in medicinal plants and some certain biological targets during a disease are still unclear in most cases. To conduct the high-throughput screening for small active molecules that can interact with biological targets, which is of great theoretical significance and practical value. The ultrafiltration mass spectrometry (UF-LC/MS) is a powerful bio-analytical method by combining affinity ultrafiltration and liquid chromatography-mass spectrometry (LC/MS), which could rapidly screen and identify small active molecules that bind to biological targets of interest at the same time. Compared with other analytical methods, affinity UF-LC/MS has the characteristics of fast, sensitive and high throughput, and is especially suitable for the complicated extracts of medicinal plants. In this review, the basic principle, characteristics and some most recent challenges in UF-LC/MS have been demonstrated. Meanwhile, the progress and applications of affinity UF-LC/MS in the discovery of the active components from natural medicinal plants and the interactions between small molecules and biological target proteins are also briefly summarised. In addition, the future directions for UF-LC/MS are also prospected. Affinity UF-LC/MS is a powerful tool in studies on the interactions between small active molecules and biological protein targets, especially in the high-throughput screening of active components from the natural medicinal plants. Copyright © 2018 John Wiley & Sons, Ltd.

  1. Water at Biological Phase Boundaries: Its Role in Interfacial Activation of Enzymes and Metabolic Pathways.

    PubMed

    Damodaran, Srinivasan

    2015-01-01

    Many life-sustaining activities in living cells occur at the membrane-water interface. The pertinent questions that we need to ask are, what are the evolutionary reasons in biology for choosing the membrane-water interface as the site for performing and/or controlling crucial biological reactions, and what is the key physical principle that is very singular to the membrane-water interface that biology exploits for regulating metabolic processes in cells? In this chapter, a hypothesis is developed, which espouses that cells control activities of membrane-bound enzymes through manipulation of the thermodynamic activity of water in the lipid-water interfacial region. The hypothesis is based on the fact that the surface pressure of a lipid monolayer is a direct measure of the thermodynamic activity of water at the lipid-water interface. Accordingly, the surface pressure-dependent activation or inactivation of interfacial enzymes is directly related to changes in the thermodynamic activity of interfacial water. Extension of this argument suggests that cells may manipulate conformations (and activities) of membrane-bound enzymes by manipulating the (re)activity of interfacial water at various locations in the membrane by localized compression or expansion of the interface. In this respect, cells may use the membrane-bound hormone receptors, lipid phase transition, and local variations in membrane lipid composition as effectors of local compression and/or expansion of membrane, and thereby local water activity. Several experimental data in the literature will be reexamined in the light of this hypothesis.

  2. Evaluation of Biologically Active Compounds from Calendula officinalis Flowers using Spectrophotometry

    PubMed Central

    2012-01-01

    Background This study aimed to quantify the active biological compounds in C. officinalis flowers. Based on the active principles and biological properties of marigolds flowers reported in the literature, we sought to obtain and characterize the molecular composition of extracts prepared using different solvents. The antioxidant capacities of extracts were assessed by using spectrophotometry to measure both absorbance of the colorimetric free radical scavenger 2,2-diphenyl-1-picrylhydrazyl (DPPH) as well as the total antioxidant potential, using the ferric reducing power (FRAP) assay. Results Spectrophotometric assays in the ultraviolet-visible (UV-VIS) region enabled identification and characterization of the full range of phenolic and flavonoids acids, and high-performance liquid chromatography (HPLC) was used to identify and quantify phenolic compounds (depending on the method of extraction). Methanol ensured more efficient extraction of flavonoids than the other solvents tested. Antioxidant activity in methanolic extracts was correlated with the polyphenol content. Conclusions The UV-VIS spectra of assimilator pigments (e.g. chlorophylls), polyphenols and flavonoids extracted from the C. officinalis flowers consisted in quantitative evaluation of compounds which absorb to wavelengths broader than 360 nm. PMID:22540963

  3. Integrating biological redesign: where synthetic biology came from and where it needs to go.

    PubMed

    Way, Jeffrey C; Collins, James J; Keasling, Jay D; Silver, Pamela A

    2014-03-27

    Synthetic biology seeks to extend approaches from engineering and computation to redesign of biology, with goals such as generating new chemicals, improving human health, and addressing environmental issues. Early on, several guiding principles of synthetic biology were articulated, including design according to specification, separation of design from fabrication, use of standardized biological parts and organisms, and abstraction. We review the utility of these principles over the past decade in light of the field's accomplishments in building complex systems based on microbial transcription and metabolism and describe the progress in mammalian cell engineering. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. [The anthropic principle in biology and radiobiology].

    PubMed

    Akif'ev, A P; Degtiarev, S V

    1999-01-01

    In accordance with the anthropic principle of the Universe the physical constants of fundamental particles of matter and the laws of their counteraction are those that an appearance of man and mind becomes possible and necessary. It is suggested to add some biological constants to the set of fundamental constants. With reparation of DNA as an example it was shown how a cell ran some parameters of Watson-Crick double helix. It was pointed that the concept of the anthropic principle of the Universe in its full body including biological constants is a key to developing of a unified theory of evolution of the Universe within the limits of scientific creationism.

  5. Why the Central Dogma: on the nature of the great biological exclusion principle.

    PubMed

    Koonin, Eugene V

    2015-09-16

    The Central Dogma of molecular biology posits that transfer of information from proteins back to nucleic acids does not occur in biological systems. I argue that the impossibility of reverse translation is indeed a major, physical exclusion principle that emerges due to the transition from the digital information carriers, nucleic acids, to analog information carriers, proteins, which involves irreversible suppression of the digital information.

  6. A precautionary principle for dual use research in the life sciences.

    PubMed

    Kuhlau, Frida; Höglund, Anna T; Evers, Kathinka; Eriksson, Stefan

    2011-01-01

    Most life science research entails dual-use complexity and may be misused for harmful purposes, e.g. biological weapons. The Precautionary Principle applies to special problems characterized by complexity in the relationship between human activities and their consequences. This article examines whether the principle, so far mainly used in environmental and public health issues, is applicable and suitable to the field of dual-use life science research. Four central elements of the principle are examined: threat, uncertainty, prescription and action. Although charges against the principle exist - for example that it stifles scientific development, lacks practical applicability and is poorly defined and vague - the analysis concludes that a Precautionary Principle is applicable to the field. Certain factors such as credibility of the threat, availability of information, clear prescriptive demands on responsibility and directives on how to act, determine the suitability and success of a Precautionary Principle. Moreover, policy-makers and researchers share a responsibility for providing and seeking information about potential sources of harm. A central conclusion is that the principle is meaningful and useful if applied as a context-dependent moral principle and allowed flexibility in its practical use. The principle may then inspire awareness-raising and the establishment of practical routines which appropriately reflect the fact that life science research may be misused for harmful purposes. © 2009 Blackwell Publishing Ltd.

  7. Designing synthetic biology.

    PubMed

    Agapakis, Christina M

    2014-03-21

    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.

  8. Bioinspired Principles for Large-Scale Networked Sensor Systems: An Overview

    PubMed Central

    Jacobsen, Rune Hylsberg; Zhang, Qi; Toftegaard, Thomas Skjødeberg

    2011-01-01

    Biology has often been used as a source of inspiration in computer science and engineering. Bioinspired principles have found their way into network node design and research due to the appealing analogies between biological systems and large networks of small sensors. This paper provides an overview of bioinspired principles and methods such as swarm intelligence, natural time synchronization, artificial immune system and intercellular information exchange applicable for sensor network design. Bioinspired principles and methods are discussed in the context of routing, clustering, time synchronization, optimal node deployment, localization and security and privacy. PMID:22163841

  9. A Photosynthesis Lab. Response of Algal Suspensions to a Gradient of Photosynthetically Active Radiation (PAR).

    ERIC Educational Resources Information Center

    Zee, Delmar Vander

    1995-01-01

    This photosynthesis exercise is intended for introductory college biology or botany courses. It is based on the principle that a closed suspension of algal cells may be expected to produce more dissolved oxygen with a greater photon fluence rate, but within limits of the photosynthetic capacity of the system. Describes materials and methods. (LZ)

  10. An Introductory Bioinformatics Exercise to Reinforce Gene Structure and Expression and Analyze the Relationship between Gene and Protein Sequences

    ERIC Educational Resources Information Center

    Almeida, Craig A.; Tardiff, Daniel F.; De Luca, Jane P.

    2004-01-01

    We have developed an introductory bioinformatics exercise for sophomore biology and biochemistry students that reinforces the understanding of the structure of a gene and the principles and events involved in its expression. In addition, the activity illustrates the severe effect mutations in a gene sequence can have on the protein product.…

  11. Approaching the Thermodynamic View of Protein Folding through the Reproduction of Anfinsen's Experiment by Undergraduate Physical Biochemistry Students

    ERIC Educational Resources Information Center

    Fernandez-Reche, Andres; Cobos, Eva S.; Luque, Irene; Ruiz-Sanz, Javier; Martinez, Jose C.

    2018-01-01

    In 1972 Christian B. Anfinsen received the Nobel Prize in Chemistry for "…his work on ribonuclease, especially concerning the connection between the amino acid sequence and the biologically active conformation." The understanding of this principle is crucial for physical biochemistry students, since protein folding studies, bio-computing…

  12. Reframing conceptual physics: Improving relevance to elementary education and sonography majors

    NASA Astrophysics Data System (ADS)

    LaFazia, David Gregory

    This study outlines the steps taken to reframe the Waves and Periodicity unit within a conceptual physics course. Beyond this unit reframing process, this paper explores the activities that made up the reframed unit and how each was developed and revised. The unit was reframed to improve relevance of the activities to the Elementary Education and Diagnostic Medical Sonography majors who make up the bulk of the course roster. The unit was reframed around ten design principles that were built on best practices from the literature, survey responses, and focused interviews. These principles support the selection of a biology-integrated themed approach to teaching physics. This is done through active and highly kinesthetic learning across three realms of human experience: physical, social, and cognitive. The unit materials were designed around making connections to students' future careers while requiring students to take progressively more responsibility in activities and assessments. Several support strategies are employed across these activities and assessments, including an energy-first, guided-inquiry approach to concept scaffolding and accommodations for diverse learners. Survey responses were solicited from physics instructors experienced with this population, Elementary Education and Sonography program advisors, and curriculum design, learning strategies, and educational technology experts. The reframed unit was reviewed by doctoral-level science education experts and revised to further improve the depth and transparency with which the design principles reframe the unit activities. The reframed unit contains a full unit plan, lesson plans, and full unit materials. These include classroom and online activities, assessments, and templates for future unit and lesson planning. Additional supplemental materials are provided to support Elementary Education and Sonography students and program advisors and also further promote the reframed unit materials and design principles. The unit is designed to be educative in nature and serves as a model for the reframing of other units. A number of the design principles are highly transdisciplinary in nature and may be applied for reframing instructional units outside of the physics and science disciplines.

  13. LeChâtelier's Principle in the Sciences

    NASA Astrophysics Data System (ADS)

    Thomsen, Volker B. E.

    2000-02-01

    LeChâtelier's principle of chemical equilibrium is actually a very general statement about systems in equilibrium and their behavior when subjected to external force or stress. Although one almost never finds mention of his name or law in other sciences, analogous principles and concepts do exist. In this note we examine some of the similar forms taken by this chemical principle in the fields of physics, geology, biology, and economics. Lenz's law in physics is an example of electromagnetic equilibrium and the geological principle of isostatic uplift concerns mechanical equilibrium. Both are strictly consequences of conservation of energy. LeChâtelier's principle deals with thermodynamic equilibrium and involves both the first and second laws of thermodynamics. The concept of homeostasis in biology and the economic law of supply and demand are both equilibrium-like principles, but involve systems in the steady state. However, all these principles involve the stability of the system under consideration and the analogies presented may be useful in the teaching of LeChâtelier's principle.

  14. The molecular turn in psychiatry: a philosophical analysis.

    PubMed

    Rudnick, Abraham

    2002-06-01

    Biological psychiatry has been dominated by a psychopharmacologically-driven neurotransmitter dysfunction paradigm. The objective of this paper is to explore a reductionist assumption underlying this paradigm, and to suggest an improvement on it. The methods used are conceptual analysis with a comparative approach, particularly using illustrations from the history of both biological psychiatry and molecular biology. The results are that complete reduction to physicochemical explanations is not fruitful, at least in the initial stages of research in the medical and life sciences, and that an appropriate (non-reducible) integrative principle--addressing a property of the whole system under study--is required for each domain of research. This is illustrated in Pauling's use of a topological integrative principle for the discovery of the functioning of proteins and in Watson and Crick's use of the notion of a genetic code as an integrative principle for the discovery of the structure of genes. The neurotransmitter dysfunction paradigm addresses single molecules and their neural pathways, yet their interactions within the CNS as a whole seem most pertinent to mental disorders such as schizophrenia. The lack within biological psychiatry of an integrative principle addressing a property of the CNS as a whole may be responsible for the empirical failure of orthomolecular psychiatry, as well as for the central role that serendipity has played in the study of mental disorders, which is dominated by the neurotransmitter paradigm. The conclusion is that research in biological psychiatry may benefit from using, at least initially, some integrative principle(s) addressing a property of the CNS as a whole, such as connectionism or a hierarchical notion.

  15. Integrated standardization concept for Angelica botanicals using quantitative NMR

    PubMed Central

    Gödecke, Tanja; Yao, Ping; Napolitano, José G.; Nikolić, Dejan; Dietz, Birgit M.; Bolton, Judy L.; van Breemen, Richard B.; Farnsworth, Norman R.; Chen, Shao-Nong; Lankin, David C.; Pauli, Guido F.

    2011-01-01

    Despite numerous in vitro/vivo and phytochemical studies, the active constituents of Angelica sinensis (AS) have not been conclusively identified for the standardization to bioactive markers. Phytochemical analyses of AS extracts and fractions that demonstrate activity in a panel of in vitro bioassays, have repeatedly pointed to ligustilide as being (associated with) the active principle(s). Due to the chemical instability of ligustilide and related issues in GC/LC analyses, new methods capable of quantifying ligustilide in mixtures that do not rely on an identical reference standard are in high demand. This study demonstrates how NMR can satisfy the requirement for simultaneous, multi-target quantification and qualitative identification. First, the AS activity was concentrated into a single fraction by RP-solid-phase extraction, as confirmed by an (anti-)estrogenicity and cytotoxicity assay. Next, a quantitative 1H NMR (qHNMR) method was established and validated using standard compounds and comparing processing methods. Subsequent 1D/2D NMR and qHNMR analysis led to the identification and quantification of ligustilide and other minor components in the active fraction, and to the development of quality criteria for authentic AS preparations. The absolute and relative quantities of ligustilide, six minor alkyl phthalides, and groups of phenylpropanoids, polyynes, and poly-unsaturated fatty acids were measured by a combination of qHNMR and 2D COSY. The qNMR approach enables multi-target quality control of the bioactive fraction, and enables the integrated biological and chemical standardization of AS botanicals. This methodology can potentially be transferred to other botanicals with active principles that act synergistically, or that contain closely related and/or constituents, which have not been conclusively identified as the active principles. PMID:21907766

  16. Mess management in microbial ecology: Rhetorical processes of disciplinary integration

    NASA Astrophysics Data System (ADS)

    McCracken, Christopher W.

    As interdisciplinary work becomes more common in the sciences, research into the rhetorical processes mediating disciplinary integration becomes more vital. This dissertation, which takes as its subject the integration of microbiology and ecology, combines a postplural approach to rhetoric of science research with Victor Turner's "social drama" analysis and a third-generation activity theory methodological framework to identify conceptual and practical conflicts in interdisciplinary work and describe how, through visual and verbal communication, scientists negotiate these conflicts. First, to understand the conflicting disciplinary principles that might impede integration, the author conducts a Turnerian analysis of a disciplinary conflict that took place in the 1960s and 70s, during which American ecologists and biologists debated whether they should participate in the International Biological Program (IBP). Participation in the IBP ultimately contributed to the emergence of ecology as a discipline distinct from biology, and Turnerian social drama analysis of the debate surrounding participation lays bare the conflicting principles separating biology and ecology. Second, to answer the question of how these conflicting principles are negotiated in practice, the author reports on a yearlong qualitative study of scientists working in a microbial ecology laboratory. Focusing specifically on two case studies from this fieldwork that illustrate the key concept of textually mediated disciplinary integration, the author's analysis demonstrates how scientific objects emerge in differently situated practices, and how these objects manage to cohere despite their multiplicity through textually mediated rhetorical processes of calibration and alignment.

  17. Completing and Adapting Models of Biological Processes

    NASA Technical Reports Server (NTRS)

    Margaria, Tiziana; Hinchey, Michael G.; Raffelt, Harald; Rash, James L.; Rouff, Christopher A.; Steffen, Bernhard

    2006-01-01

    We present a learning-based method for model completion and adaptation, which is based on the combination of two approaches: 1) R2D2C, a technique for mechanically transforming system requirements via provably equivalent models to running code, and 2) automata learning-based model extrapolation. The intended impact of this new combination is to make model completion and adaptation accessible to experts of the field, like biologists or engineers. The principle is briefly illustrated by generating models of biological procedures concerning gene activities in the production of proteins, although the main application is going to concern autonomic systems for space exploration.

  18. Biological imaging with coherent Raman scattering microscopy: a tutorial

    PubMed Central

    Alfonso-García, Alba; Mittal, Richa; Lee, Eun Seong; Potma, Eric O.

    2014-01-01

    Abstract. Coherent Raman scattering (CRS) microscopy is gaining acceptance as a valuable addition to the imaging toolset of biological researchers. Optimal use of this label-free imaging technique benefits from a basic understanding of the physical principles and technical merits of the CRS microscope. This tutorial offers qualitative explanations of the principles behind CRS microscopy and provides information about the applicability of this nonlinear optical imaging approach for biological research. PMID:24615671

  19. Plant synthetic biology.

    PubMed

    Liu, Wusheng; Stewart, C Neal

    2015-05-01

    Plant synthetic biology is an emerging field that combines engineering principles with plant biology toward the design and production of new devices. This emerging field should play an important role in future agriculture for traditional crop improvement, but also in enabling novel bioproduction in plants. In this review we discuss the design cycles of synthetic biology as well as key engineering principles, genetic parts, and computational tools that can be utilized in plant synthetic biology. Some pioneering examples are offered as a demonstration of how synthetic biology can be used to modify plants for specific purposes. These include synthetic sensors, synthetic metabolic pathways, and synthetic genomes. We also speculate about the future of synthetic biology of plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. The biological correction is the new way of preservation of the Face of the Earth

    NASA Astrophysics Data System (ADS)

    Popov, Alexander

    2014-05-01

    The major links of terrestrial ecosystems functioning are: composted organic material with mull humus type, nitrogen-fixing microorganisms and litholytic organisms, which capable of active biological weathering of minerals and/or rock in the soil. Now the main ways of influence on plant-soil system functioning are physical and chemical correction. Physical correction is the system of different soil cultivation and land reclamation. It directed on creation and maintenance of favorable water, thermal and air regimes and also the biological activity of soils for crops. Although the general tendency of agriculture is minimized of tillage (strip-till, mini-till and no-till), nevertheless the intensive cultivation is widely used in modern agriculture. Chemical correction is the agriculture chemicalixation. It directed on regulation of plant producing by replenishment of plant, mineral nutrition elements in soils, by foliar nutrition using water solutions of macro- and microelements, and by regulation of acidic and salt soil regimes. In this case the plant protection against the pests and infections is carried out by various pesticides. This way of correction is completely realized in agriculture, but it doesn't consider the natural laws due to plants together with the soil from the interconnected and interdependent system. The continuing increase of agriculture chemicalixation simultaneously with a repeated tillage is led to loss of the major links of plant-soil systems functioning and to the degradation of a soil cover. Such way of plant productivity is a deadlock. New evolutionary way of preservation of the Face of the Earth is biological correction of plant-soil system functioning. A gist of this correction is the replenishment of the lost plant-soil system links. Biological correction leans on scientific achievements of modern biotechnologies, such as: vermicomposting, microbiologic specimens, physiologically active substances, biological agents of plant protection, etc. Methods of biological correction are exact biological analogs of natural links and so they can't cause the negative phenomena of plant growth and development. The principle of biological interrelationship is the base of these methods. At the heart of these methods the principle of biological compliance lies. Herewith, physiological features of plants are considered necessary. There are following main biological correction methods of plant productivity: (i) biological amelioration of soils (using of vermicomposts, earthworms, microbiologic specimens, organic and green manure, etc.); (ii) infection of plants by cultures of living microorganisms (for plant nutrition and protection); (iii) inputting of biological insecticides into plants (allows to fight even against larvae of mining insects successfully); (iv) influence on a plant metabolism by physiologically active substances (such as solutions of humic substances in particular); (v) creation of multilayered mats for gardening of deserts. The field experiments in working conditions, which were carried out in different climatic zones, bear evidence of efficiency of biological correction methods. In our opinion biological correction methods are capable to support and/or restore land-cover, to stop a degradation, and by that to prevent a disfigurement of the Face of the Earth.

  1. Structural Perspective on Enzymatic Halogenation

    PubMed Central

    2008-01-01

    Simple halogen substituents frequently afford key structural features that account for the potency and selectivity of natural products, including antibiotics and hormones. For example, when a single chlorine atom on the antibiotic vancomycin is replaced by hydrogen, the resulting antibacterial activity decreases by up to 70% (HarrisC. M.; KannanR.; KopeckaH.; HarrisT. M.J. Am. Chem. Soc.1985, 107, 6652−6658). This Account analyzes how structure underlies mechanism in halogenases, the molecular machines designed by nature to incorporate halogens into diverse substrates. Traditional synthetic methods of integrating halogens into complex molecules are often complicated by a lack of specificity and regioselectivity. Nature, however, has developed a variety of elegant mechanisms for halogenating specific substrates with both regio- and stereoselectivity. An improved understanding of the biological routes toward halogenation could lead to the development of novel synthetic methods for the creation of new compounds with enhanced functions. Already, researchers have co-opted a fluorinase from the microorganism Streptomyces cattleya to produce 18F-labeled molecules for use in positron emission tomography (PET) (DengH.; CobbS. L.; GeeA. D.; LockhartA.; MartarelloL.; McGlincheyR. P.; O’HaganD.; OnegaM.Chem. Commun.2006, 652−654). Therefore, the discovery and characterization of naturally occurring enzymatic halogenation mechanisms has become an active area of research. The catalogue of known halogenating enzymes has expanded from the familiar haloperoxidases to include oxygen-dependent enzymes and fluorinases. Recently, the discovery of a nucleophilic halogenase that catalyzes chlorinations has expanded the repertoire of biological halogenation chemistry (DongC.; HuangF.; DengH.; SchaffrathC.; SpencerJ. B.; O’HaganD.; NaismithJ. H.Nature2004, 427, 561−56514765200). Structural characterization has provided a basis toward a mechanistic understanding of the specificity and chemistry of these enzymes. In particular, the latest crystallographic snapshots of active site architecture and halide binding sites have provided key insights into enzyme catalysis. Herein is a summary of the five classes of halogenases, focusing on the three most recently discovered: flavin-dependent halogenases, non-heme iron-dependent halogenases, and nucleophilic halogenases. Further, the potential roles of halide-binding sites in determining halide selectivity are discussed, as well as whether or not binding-site composition is always a seminal factor for selectivity. Expanding our understanding of the basic chemical principles that dictate the activity of the halogenases will advance both biology and chemistry. A thorough mechanistic analysis will elucidate the biological principles that dictate specificity, and the application of those principles to new synthetic techniques will expand the utility of halogenations in small-molecule development. PMID:18774824

  2. Can Simple Biophysical Principles Yield Complicated Biological Functions?

    NASA Astrophysics Data System (ADS)

    Liphardt, Jan

    2011-03-01

    About once a year, a new regulatory paradigm is discovered in cell biology. As of last count, eukaryotic cells have more than 40 distinct ways of regulating protein concentration and function. Regulatory possibilities include site-specific phosphorylation, epigenetics, alternative splicing, mRNA (re)localization, and modulation of nucleo-cytoplasmic transport. This raises a simple question. Do all the remarkable things cells do, require an intricately choreographed supporting cast of hundreds of molecular machines and associated signaling networks? Alternatively, are there a few simple biophysical principles that can generate apparently very complicated cellular behaviors and functions? I'll discuss two problems, spatial organization of the bacterial chemotaxis system and nucleo-cytoplasmic transport, where the latter might be true. In both cases, the ability to precisely quantify biological organization and function, at the single-molecule level, helped to find signatures of basic biological organizing principles.

  3. A review of selected pumping systems in nature and engineering--potential biomimetic concepts for improving displacement pumps and pulsation damping.

    PubMed

    Bach, D; Schmich, F; Masselter, T; Speck, T

    2015-09-03

    The active transport of fluids by pumps plays an essential role in engineering and biology. Due to increasing energy costs and environmental issues, topics like noise reduction, increase of efficiency and enhanced robustness are of high importance in the development of pumps in engineering. The study compares pumps in biology and engineering and assesses biomimetic potentials for improving man-made pumping systems. To this aim, examples of common challenges, applications and current biomimetic research for state-of-the art pumps are presented. The biomimetic research is helped by the similar configuration of many positive displacement pumping systems in biology and engineering. In contrast, the configuration and underlying pumping principles for fluid dynamic pumps (FDPs) differ to a greater extent in biology and engineering. However, progress has been made for positive displacement as well as for FDPs by developing biomimetic devices with artificial muscles and cilia that improve energetic efficiency and fail-safe operation or reduce noise. The circulatory system of vertebrates holds a high biomimetic potential for the damping of pressure pulsations, a common challenge in engineering. Damping of blood pressure pulsation results from a nonlinear viscoelastic behavior of the artery walls which represent a complex composite material. The transfer of the underlying functional principle could lead to an improvement of existing technical solutions and be used to develop novel biomimetic damping solutions. To enhance efficiency or thrust of man-made fluid transportation systems, research on jet propulsion in biology has shown that a pulsed jet can be tuned to either maximize thrust or efficiency. The underlying principle has already been transferred into biomimetic applications in open channel water systems. Overall there is a high potential to learn from nature in order to improve pumping systems for challenges like the reduction of pressure pulsations, increase of jet propulsion efficiency or the reduction of wear.

  4. Virtual immunology: software for teaching basic immunology.

    PubMed

    Berçot, Filipe Faria; Fidalgo-Neto, Antônio Augusto; Lopes, Renato Matos; Faggioni, Thais; Alves, Luiz Anastácio

    2013-01-01

    As immunology continues to evolve, many educational methods have found difficulty in conveying the degree of complexity inherent in its basic principles. Today, the teaching-learning process in such areas has been improved with tools such as educational software. This article introduces "Virtual Immunology," a software program available free of charge in Portuguese and English, which can be used by teachers and students in physiology, immunology, and cellular biology classes. We discuss the development of the initial two modules: "Organs and Lymphoid Tissues" and "Inflammation" and the use of interactive activities to provide microscopic and macroscopic understanding in immunology. Students, both graduate and undergraduate, were questioned along with university level professors about the quality of the software and intuitiveness of use, facility of navigation, and aesthetic organization using a Likert scale. An overwhelmingly satisfactory result was obtained with both students and immunology teachers. Programs such as "Virtual Immunology" are offering more interactive, multimedia approaches to complex scientific principles that increase student motivation, interest, and comprehension. © 2013 by The International Union of Biochemistry and Molecular Biology.

  5. The Dark Matter of Biology.

    PubMed

    Ross, Jennifer L

    2016-09-06

    The inside of the cell is full of important, yet invisible species of molecules and proteins that interact weakly but couple together to have huge and important effects in many biological processes. Such "dark matter" inside cells remains mostly hidden, because our tools were developed to investigate strongly interacting species and folded proteins. Example dark-matter species include intrinsically disordered proteins, posttranslational states, ion species, and rare, transient, and weak interactions undetectable by biochemical assays. The dark matter of biology is likely to have multiple, vital roles to regulate signaling, rates of reactions, water structure and viscosity, crowding, and other cellular activities. We need to create new tools to image, detect, and understand these dark-matter species if we are to truly understand fundamental physical principles of biology. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  6. Principles for integrating reactive species into in vivo biological processes: Examples from exercise physiology.

    PubMed

    Margaritelis, Nikos V; Cobley, James N; Paschalis, Vassilis; Veskoukis, Aristidis S; Theodorou, Anastasios A; Kyparos, Antonios; Nikolaidis, Michalis G

    2016-04-01

    The equivocal role of reactive species and redox signaling in exercise responses and adaptations is an example clearly showing the inadequacy of current redox biology research to shed light on fundamental biological processes in vivo. Part of the answer probably relies on the extreme complexity of the in vivo redox biology and the limitations of the currently applied methodological and experimental tools. We propose six fundamental principles that should be considered in future studies to mechanistically link reactive species production to exercise responses or adaptations: 1) identify and quantify the reactive species, 2) determine the potential signaling properties of the reactive species, 3) detect the sources of reactive species, 4) locate the domain modified and verify the (ir)reversibility of post-translational modifications, 5) establish causality between redox and physiological measurements, 6) use selective and targeted antioxidants. Fulfilling these principles requires an idealized human experimental setting, which is certainly a utopia. Thus, researchers should choose to satisfy those principles, which, based on scientific evidence, are most critical for their specific research question. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Material Science

    NASA Image and Video Library

    2002-08-06

    Twila Schneider of Infinity Technology in Huntsville, AL, uses a small sand displacement box to explain the principles of the Mechanics of Granular Materials (MGM-III) experiment to two young Virginia students. The activity was part of the Space Research and You education event held by NASA's Office of Biological and Physical Research on June 25, 2002, in Arlington, VA, to highlight the research that will be conducted on STS-107.

  8. Enhancing Tumor Drug Delivery by Laser-Activated Vascular Barrier Disruption

    DTIC Science & Technology

    2006-12-01

    increased, which leads to normal tissue toxicity . This delivery problem not only limits the clinical application of existing chemotherapeutics, but also...principles and uses photochemical reactions to generate biological effectors, such as reactive oxygen species (ROS), which cause oxidative damage to...liposomes, mi- celles, and biodegradable nanoparticles , or conju- gated with hydrophilic polymers.6 It is likely that although some level of

  9. Terminator Operon Reporter: combining a transcription termination switch with reporter technology for improved gene synthesis and synthetic biology applications.

    PubMed

    Zampini, Massimiliano; Mur, Luis A J; Rees Stevens, Pauline; Pachebat, Justin A; Newbold, C James; Hayes, Finbarr; Kingston-Smith, Alison

    2016-05-25

    Synthetic biology is characterized by the development of novel and powerful DNA fabrication methods and by the application of engineering principles to biology. The current study describes Terminator Operon Reporter (TOR), a new gene assembly technology based on the conditional activation of a reporter gene in response to sequence errors occurring at the assembly stage of the synthetic element. These errors are monitored by a transcription terminator that is placed between the synthetic gene and reporter gene. Switching of this terminator between active and inactive states dictates the transcription status of the downstream reporter gene to provide a rapid and facile readout of the accuracy of synthetic assembly. Designed specifically and uniquely for the synthesis of protein coding genes in bacteria, TOR allows the rapid and cost-effective fabrication of synthetic constructs by employing oligonucleotides at the most basic purification level (desalted) and without the need for costly and time-consuming post-synthesis correction methods. Thus, TOR streamlines gene assembly approaches, which are central to the future development of synthetic biology.

  10. Team-teaching a current events-based biology course for nonmajors.

    PubMed

    Bondos, Sarah E; Phillips, Dereth

    2008-01-01

    Rice University has created a team-taught interactive biology course for nonmajors with a focus on cutting edge biology in the news-advances in biotechnology, medicine, and science policy, along with the biological principles and methodology upon which these advances are based. The challenges inherent to teaching current topics were minimized by team-teaching the course, providing knowledgeable and enthusiastic lecturers for every topic while distributing the effort required to update material. Postdoctoral associates and advanced graduate students served as lecturers, providing an opportunity for them to develop their teaching skills and learn to communicate effectively with nonscientists on newsworthy topics related to their research. Laboratory tours, in-class demonstrations, and mock-ups helped lecturers convey surprisingly advanced ideas with students who lacked a strong theoretical or practical science background. A faculty member and co-coordinator administer the class, organize class activities, and mentor the speakers on teaching techniques and lecture design. Course design, lecture topics, hands-on activities, and approaches to successfully solve the difficulties inherent to team teaching are discussed. Course evaluations reflect student involvement in, and enjoyment of, the class. Copyright © 2008 International Union of Biochemistry and Molecular Biology, Inc.

  11. On the analysis of complex biological supply chains: From Process Systems Engineering to Quantitative Systems Pharmacology.

    PubMed

    Rao, Rohit T; Scherholz, Megerle L; Hartmanshenn, Clara; Bae, Seul-A; Androulakis, Ioannis P

    2017-12-05

    The use of models in biology has become particularly relevant as it enables investigators to develop a mechanistic framework for understanding the operating principles of living systems as well as in quantitatively predicting their response to both pathological perturbations and pharmacological interventions. This application has resulted in a synergistic convergence of systems biology and pharmacokinetic-pharmacodynamic modeling techniques that has led to the emergence of quantitative systems pharmacology (QSP). In this review, we discuss how the foundational principles of chemical process systems engineering inform the progressive development of more physiologically-based systems biology models.

  12. Separation and sorting of cells in microsystems using physical principles

    NASA Astrophysics Data System (ADS)

    Lee, Gi-Hun; Kim, Sung-Hwan; Ahn, Kihoon; Lee, Sang-Hoon; Park, Joong Yull

    2016-01-01

    In the last decade, microfabrication techniques have been combined with microfluidics and applied to cell biology. Utilizing such new techniques, various cell studies have been performed for the research of stem cells, immune cells, cancer, neurons, etc. Among the various biological applications of microtechnology-based platforms, cell separation technology has been highly regarded in biological and clinical fields for sorting different types of cells, finding circulating tumor cells (CTCs), and blood cell separation, amongst other things. Many cell separation methods have been created using various physical principles. Representatively, these include hydrodynamic, acoustic, dielectrophoretic, magnetic, optical, and filtering methods. In this review, each of these methods will be introduced, and their physical principles and sample applications described. Each physical principle has its own advantages and disadvantages. The engineers who design the systems and the biologists who use them should understand the pros and cons of each method or principle, to broaden the use of microsystems for cell separation. Continuous development of microsystems for cell separation will lead to new opportunities for diagnosing CTCs and cancer metastasis, as well as other elements in the bloodstream.

  13. Hybrid semi-parametric mathematical systems: bridging the gap between systems biology and process engineering.

    PubMed

    Teixeira, Ana P; Carinhas, Nuno; Dias, João M L; Cruz, Pedro; Alves, Paula M; Carrondo, Manuel J T; Oliveira, Rui

    2007-12-01

    Systems biology is an integrative science that aims at the global characterization of biological systems. Huge amounts of data regarding gene expression, proteins activity and metabolite concentrations are collected by designing systematic genetic or environmental perturbations. Then the challenge is to integrate such data in a global model in order to provide a global picture of the cell. The analysis of these data is largely dominated by nonparametric modelling tools. In contrast, classical bioprocess engineering has been primarily founded on first principles models, but it has systematically overlooked the details of the embedded biological system. The full complexity of biological systems is currently assumed by systems biology and this knowledge can now be taken by engineers to decide how to optimally design and operate their processes. This paper discusses possible methodologies for the integration of systems biology and bioprocess engineering with emphasis on applications involving animal cell cultures. At the mathematical systems level, the discussion is focused on hybrid semi-parametric systems as a way to bridge systems biology and bioprocess engineering.

  14. Pluripotent stem cell-derived organoids: using principles of developmental biology to grow human tissues in a dish.

    PubMed

    McCauley, Heather A; Wells, James M

    2017-03-15

    Pluripotent stem cell (PSC)-derived organoids are miniature, three-dimensional human tissues generated by the application of developmental biological principles to PSCs in vitro The approach to generate organoids uses a combination of directed differentiation, morphogenetic processes, and the intrinsically driven self-assembly of cells that mimics organogenesis in the developing embryo. The resulting organoids have remarkable cell type complexity, architecture and function similar to their in vivo counterparts. In the past five years, human PSC-derived organoids with components of all three germ layers have been generated, resulting in the establishment of a new human model system. Here, and in the accompanying poster, we provide an overview of how principles of developmental biology have been essential for generating human organoids in vitro , and how organoids are now being used as a primary research tool to investigate human developmental biology. © 2017. Published by The Company of Biologists Ltd.

  15. A Concert between Biology and Biomechanics: The Influence of the Mechanical Environment on Bone Healing

    PubMed Central

    Glatt, Vaida; Evans, Christopher H.; Tetsworth, Kevin

    2017-01-01

    In order to achieve consistent and predictable fracture healing, a broad spectrum of growth factors are required to interact with one another in a highly organized response. Critically important, the mechanical environment around the fracture site will significantly influence the way bone heals, or if it heals at all. The role of the various biological factors, the timing, and spatial relationship of their introduction, and how the mechanical environment orchestrates this activity, are all crucial aspects to consider. This review will synthesize decades of work and the acquired knowledge that has been used to develop new treatments and technologies for the regeneration and healing of bone. Moreover, it will discuss the current state of the art in experimental and clinical studies concerning the application of these mechano-biological principles to enhance bone healing, by controlling the mechanical environment under which bone regeneration takes place. This includes everything from the basic principles of fracture healing, to the influence of mechanical forces on bone regeneration, and how this knowledge has influenced current clinical practice. Finally, it will examine the efforts now being made for the integration of this research together with the findings of complementary studies in biology, tissue engineering, and regenerative medicine. By bringing together these diverse disciplines in a cohesive manner, the potential exists to enhance fracture healing and ultimately improve clinical outcomes. PMID:28174539

  16. Matching the Neurobiology of Learning to Teaching Principles

    ERIC Educational Resources Information Center

    Moffett, Nelle; Fleisher, Steven C.

    2013-01-01

    The authors describe principles of good teaching drawn from meta-analyses of research on teaching effectiveness. Recent developments in neurobiology are presented and aligned to provide biological support for these principles. To make it easier for college faculty to try out sample instructional strategies, the authors map principles of good…

  17. [Ethical aspects of biological sample banks].

    PubMed

    Cambon-Thomsen, A; Rial-Sebbag, E

    2003-02-01

    Numerous activities in the domain of epidemiology require the constitution or the use of biological sample banks. Such biobanks raise ethical issues. A number of recommendations are applicable to this field, in France and elsewhere. Major principles applicable to biobanks include the respect of person's autonomy, the respect of human body, the respect of confidentiality. These principles are translated into practices through the following procedures: relevant information to the persons regarding their sample management prior to informed consent, opinion of an independent ethics committee, actual implementation of conditions for protecting samples and data. However, although those principles may appear quite simple and obvious, in the context of a largely international practice of research and given the large variety of biobanks, it is not always obvious for researchers to find their way. The attitudes vary between countries, there are numerous texts for various types of biobanks, the same texts raise different interpretations in different institutions, there are new ethical opinions expressed, and mainly the novelty of questions raised by the uses of samples that are possible today, especially in genetics, and were not foreseeable at the time of sampling make the field difficult in practice. This article reviews the types of biobanks, the relevant ethical issues. It also underlines the still unclear or ambiguous situations using some examples of practical situations.

  18. A Novel Tool to Facilitate the Learning of Thermodynamic Principles by Undergraduate Students of the Biological Area

    ERIC Educational Resources Information Center

    Carvalho, Eduardo O.; Araki, Marcelo K.; Freitas, Sergio F.; de Godoy, Carlos M. G.; Faljoni-Alario, Adelaide; Frare-Junior, Pedro L.; Nantes, Iseli L.

    2009-01-01

    This study describes the application and evaluation of a novel didactic tool (thermodynamic device) developed for students in the area of biology who have conceptual deficiencies that render the learning of thermodynamic principles difficult. Systems of communicant vessels with equal and different compartments were constructed to correlate the…

  19. Assessing Students' Ability to Trace Matter in Dynamic Systems in Cell Biology

    ERIC Educational Resources Information Center

    Wilson, Christopher D.; Anderson, Charles W.; Heidemann, Merle; Merrill, John E.; Merritt, Brett W.; Richmond, Gail; Sibley, Duncan F.; Parker, Joyce M.

    2006-01-01

    College-level biology courses contain many complex processes that are often taught and learned as detailed narratives. These processes can be better understood by perceiving them as dynamic systems that are governed by common fundamental principles. Conservation of matter is such a principle, and thus tracing matter is an essential step in…

  20. Hibiscus sabdariffa L., roselle calyx, from ethnobotany to pharmacology.

    PubMed

    Carvajal-Zarrabal, Octavio; Barradas-Dermitz, Dulce María; Orta-Flores, Zaida; Hayward-Jones, Patricia Margaret; Nolasco-Hipólito, Cirilo; Aguilar-Uscanga, M Guadalupe; Miranda-Medina, Anilú; Bujang, Kopli Bin

    2012-01-01

    Using MEDLINE and SCOPUS databases, a review of the literature from the pioneering study of 1991 until 2010 was performed on the effects on biological models of Hibiscus sabdariffa L. roselle calyx, its extracts mainly in polar solvents, or pure components found in extracts, as well as their possible relationship to these effects. Three relevant effects on lipid metabolism, antihypertensive activity, and apoptosis were observed. Our chronological review of the studies mentioned in the literature provides another opportunity to see how humans compile scientific knowledge of a chemical structure-physiological activity relationship starting from an ethnobotanical-ethnopharmagognosy contribution. The chemical components that are the main active principles in the physiological activities of Hibiscus sabdariffa L. calyx are anthocyanins and polyphenols (protocatechuic acid and quercetin). Advances have also been made in the elucidation of action mechanisms. Additionally, it has become clear that the lack of standardization in terms of chemical components of the material arising from Hibiscus sabdariffa L. used in testing on biological models imposes limits on the possibility of carrying out comparative analyses between studies. Fortunately, more recent studies are overcoming this obstacle by reporting component concentrations of assumed active principles; however, complete analysis of the extract, if this is to be considered as a therapeutic agent, is not commonly reported in the aforesaid studies. If one of the eventual scenarios for Hibiscus sabdariffa L. calyx is as a therapeutic agent in communities with economic limitations, then studies of a pharmacological nature should guarantee the effectiveness, safety, and tolerability of this material, which is widely accepted to be associated with chemical complexity, thus making this knowledge necessary.

  1. Hibiscus sabdariffa L., roselle calyx, from ethnobotany to pharmacology

    PubMed Central

    Carvajal-Zarrabal, Octavio; Barradas-Dermitz, Dulce María; Orta-Flores, Zaida; Hayward-Jones, Patricia Margaret; Nolasco-Hipólito, Cirilo; Aguilar-Uscanga, M Guadalupe; Miranda-Medina, Anilú; Bujang, Kopli Bin

    2012-01-01

    Using MEDLINE and SCOPUS databases, a review of the literature from the pioneering study of 1991 until 2010 was performed on the effects on biological models of Hibiscus sabdariffa L. roselle calyx, its extracts mainly in polar solvents, or pure components found in extracts, as well as their possible relationship to these effects. Three relevant effects on lipid metabolism, antihypertensive activity, and apoptosis were observed. Our chronological review of the studies mentioned in the literature provides another opportunity to see how humans compile scientific knowledge of a chemical structure–physiological activity relationship starting from an ethnobotanical–ethnopharmagognosy contribution. The chemical components that are the main active principles in the physiological activities of Hibiscus sabdariffa L. calyx are anthocyanins and polyphenols (protocatechuic acid and quercetin). Advances have also been made in the elucidation of action mechanisms. Additionally, it has become clear that the lack of standardization in terms of chemical components of the material arising from Hibiscus sabdariffa L. used in testing on biological models imposes limits on the possibility of carrying out comparative analyses between studies. Fortunately, more recent studies are overcoming this obstacle by reporting component concentrations of assumed active principles; however, complete analysis of the extract, if this is to be considered as a therapeutic agent, is not commonly reported in the aforesaid studies. If one of the eventual scenarios for Hibiscus sabdariffa L. calyx is as a therapeutic agent in communities with economic limitations, then studies of a pharmacological nature should guarantee the effectiveness, safety, and tolerability of this material, which is widely accepted to be associated with chemical complexity, thus making this knowledge necessary. PMID:27186114

  2. [Research progress of mammalian synthetic biology in biomedical field].

    PubMed

    Yang, Linfeng; Yin, Jianli; Wang, Meiyan; Ye, Haifeng

    2017-03-25

    Although still in its infant stage, synthetic biology has achieved remarkable development and progress during the past decade. Synthetic biology applies engineering principles to design and construct gene circuits uploaded into living cells or organisms to perform novel or improved functions, and it has been widely used in many fields. In this review, we describe the recent advances of mammalian synthetic biology for the treatment of diseases. We introduce common tools and design principles of synthetic gene circuits, and then we demonstrate open-loop gene circuits induced by different trigger molecules used in disease diagnosis and close-loop gene circuits used for biomedical applications. Finally, we discuss the perspectives and potential challenges of synthetic biology for clinical applications.

  3. Borreria and Spermacoce species (Rubiaceae): A review of their ethnomedicinal properties, chemical constituents, and biological activities

    PubMed Central

    Conserva, Lucia Maria; Ferreira, Jesu Costa

    2012-01-01

    Borreira and Spermacoce are genera of Rubiaceae widespread in tropical and subtropical America, Africa, Asia, and Europe. Based on its fruits morphology they are considered by many authors to be distinct genera and most others, however, prefer to combine the two taxa under the generic name Spermacoce. Whereas the discussion is still unclear, in this work they were considered as synonyms. Some species of these genera play an important role in traditional medicine in Africa, Asia, Europe, and South America. Some of these uses include the treatment of malaria, diarrheal and other digestive problems, skin diseases, fever, hemorrhage, urinary and respiratory infections, headache, inflammation of eye, and gums. To date, more than 60 compounds have been reported from Borreria and Spermacoce species including alkaloids, iridoids, flavonoids, terpenoids, and other compounds. Studies have confirmed that extracts from Borreria and Spermacoce species as well as their isolated compounds possess diverse biological activities, including anti-inflammatory, antitumor, antimicrobial, larvicidal, antioxidant, gastrointestinal, anti-ulcer, and hepatoprotective, with alkaloids and iridoids as the major active principles. This paper briefly reviews the ethnomedicinal uses, phytochemistry, and biological activities of some isolated compounds and extracts of both genera. PMID:22654404

  4. Shilajit: A Natural Phytocomplex with Potential Procognitive Activity

    PubMed Central

    Carrasco-Gallardo, Carlos; Guzmán, Leonardo; Maccioni, Ricardo B.

    2012-01-01

    Shilajit is a natural substance found mainly in the Himalayas, formed for centuries by the gradual decomposition of certain plants by the action of microorganisms. It is a potent and very safe dietary supplement, restoring the energetic balance and potentially able to prevent several diseases. Recent investigations point to an interesting medical application toward the control of cognitive disorders associated with aging, and cognitive stimulation. Thus, fulvic acid, the main active principle, blocks tau self-aggregation, opening an avenue toward the study of Alzheimer's therapy. In essence, this is a nutraceutical product of demonstrated benefits for human health. Considering the expected impact of shilajit usage in the medical field, especially in the neurological sciences, more investigations at the basic biological level as well as clinical trials are necessary, in order to understand how organic molecules of shilajit and particularly fulvic acid, one of the active principles, and oligoelements act at both the molecular and cellular levels and in the whole organism. PMID:22482077

  5. Shilajit: a natural phytocomplex with potential procognitive activity.

    PubMed

    Carrasco-Gallardo, Carlos; Guzmán, Leonardo; Maccioni, Ricardo B

    2012-01-01

    Shilajit is a natural substance found mainly in the Himalayas, formed for centuries by the gradual decomposition of certain plants by the action of microorganisms. It is a potent and very safe dietary supplement, restoring the energetic balance and potentially able to prevent several diseases. Recent investigations point to an interesting medical application toward the control of cognitive disorders associated with aging, and cognitive stimulation. Thus, fulvic acid, the main active principle, blocks tau self-aggregation, opening an avenue toward the study of Alzheimer's therapy. In essence, this is a nutraceutical product of demonstrated benefits for human health. Considering the expected impact of shilajit usage in the medical field, especially in the neurological sciences, more investigations at the basic biological level as well as clinical trials are necessary, in order to understand how organic molecules of shilajit and particularly fulvic acid, one of the active principles, and oligoelements act at both the molecular and cellular levels and in the whole organism.

  6. Broca's area and the language instinct.

    PubMed

    Musso, Mariacristina; Moro, Andrea; Glauche, Volkmar; Rijntjes, Michel; Reichenbach, Jürgen; Büchel, Christian; Weiller, Cornelius

    2003-07-01

    Language acquisition in humans relies on abilities like abstraction and use of syntactic rules, which are absent in other animals. The neural correlate of acquiring new linguistic competence was investigated with two functional magnetic resonance imaging (fMRI) studies. German native speakers learned a sample of 'real' grammatical rules of different languages (Italian or Japanese), which, although parametrically different, follow the universal principles of grammar (UG). Activity during this task was compared with that during a task that involved learning 'unreal' rules of language. 'Unreal' rules were obtained manipulating the original two languages; they used the same lexicon as Italian or Japanese, but were linguistically illegal, as they violated the principles of UG. Increase of activation over time in Broca's area was specific for 'real' language acquisition only, independent of the kind of language. Thus, in Broca's area, biological constraints and language experience interact to enable linguistic competence for a new language.

  7. Organic core-sheath nanowire artificial synapses with femtojoule energy consumption.

    PubMed

    Xu, Wentao; Min, Sung-Yong; Hwang, Hyunsang; Lee, Tae-Woo

    2016-06-01

    Emulation of biological synapses is an important step toward construction of large-scale brain-inspired electronics. Despite remarkable progress in emulating synaptic functions, current synaptic devices still consume energy that is orders of magnitude greater than do biological synapses (~10 fJ per synaptic event). Reduction of energy consumption of artificial synapses remains a difficult challenge. We report organic nanowire (ONW) synaptic transistors (STs) that emulate the important working principles of a biological synapse. The ONWs emulate the morphology of nerve fibers. With a core-sheath-structured ONW active channel and a well-confined 300-nm channel length obtained using ONW lithography, ~1.23 fJ per synaptic event for individual ONW was attained, which rivals that of biological synapses. The ONW STs provide a significant step toward realizing low-energy-consuming artificial intelligent electronics and open new approaches to assembling soft neuromorphic systems with nanometer feature size.

  8. Is synthetic biology mechanical biology?

    PubMed

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  9. On Crowd-verification of Biological Networks

    PubMed Central

    Ansari, Sam; Binder, Jean; Boue, Stephanie; Di Fabio, Anselmo; Hayes, William; Hoeng, Julia; Iskandar, Anita; Kleiman, Robin; Norel, Raquel; O’Neel, Bruce; Peitsch, Manuel C.; Poussin, Carine; Pratt, Dexter; Rhrissorrakrai, Kahn; Schlage, Walter K.; Stolovitzky, Gustavo; Talikka, Marja

    2013-01-01

    Biological networks with a structured syntax are a powerful way of representing biological information generated from high density data; however, they can become unwieldy to manage as their size and complexity increase. This article presents a crowd-verification approach for the visualization and expansion of biological networks. Web-based graphical interfaces allow visualization of causal and correlative biological relationships represented using Biological Expression Language (BEL). Crowdsourcing principles enable participants to communally annotate these relationships based on literature evidences. Gamification principles are incorporated to further engage domain experts throughout biology to gather robust peer-reviewed information from which relationships can be identified and verified. The resulting network models will represent the current status of biological knowledge within the defined boundaries, here processes related to human lung disease. These models are amenable to computational analysis. For some period following conclusion of the challenge, the published models will remain available for continuous use and expansion by the scientific community. PMID:24151423

  10. Child Interacts with a Shear Strength Demonstrator

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Twila Schneider of Infinity Technology in Huntsville, AL, uses a small sand displacement box to explain the principles of the Mechanics of Granular Materials (MGM-III) experiment to two young Virginia students. The activity was part of the Space Research and You education event held by NASA's Office of Biological and Physical Research on June 25, 2002, in Arlington, VA, to highlight the research that will be conducted on STS-107.

  11. A comprehensive experiment for molecular biology: Determination of single nucleotide polymorphism in human REV3 gene using PCR-RFLP.

    PubMed

    Zhang, Xu; Shao, Meng; Gao, Lu; Zhao, Yuanyuan; Sun, Zixuan; Zhou, Liping; Yan, Yongmin; Shao, Qixiang; Xu, Wenrong; Qian, Hui

    2017-07-08

    Laboratory exercise is helpful for medical students to understand the basic principles of molecular biology and to learn about the practical applications of molecular biology. We have designed a lab course on molecular biology about the determination of single nucleotide polymorphism (SNP) in human REV3 gene, the product of which is a subunit of DNA polymerase ζ and SNPs in this gene are associated with altered susceptibility to cancer. This newly designed experiment is composed of three parts, including genomic DNA extraction, gene amplification by PCR, and genotyping by RFLP. By combining these activities, the students are not only able to learn a series of biotechniques in molecular biology, but also acquire the ability to link the learned knowledge with practical applications. This comprehensive experiment will help the medical students improve the conceptual understanding of SNP and the technical understanding of SNP detection. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(4):299-304, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

  12. A geometric initial guess for localized electronic orbitals in modular biological systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beckman, P. G.; Fattebert, J. L.; Lau, E. Y.

    Recent first-principles molecular dynamics algorithms using localized electronic orbitals have achieved O(N) complexity and controlled accuracy in simulating systems with finite band gaps. However, accurately deter- mining the centers of these localized orbitals during simulation setup may require O(N 3) operations, which is computationally infeasible for many biological systems. We present an O(N) approach for approximating orbital centers in proteins, DNA, and RNA which uses non-localized solutions for a set of fixed-size subproblems to create a set of geometric maps applicable to larger systems. This scalable approach, used as an initial guess in the O(N) first-principles molecular dynamics code MGmol,more » facilitates first-principles simulations in biological systems of sizes which were previously impossible.« less

  13. Rethinking biology instruction: The application of DNR-based instruction to the learning and teaching of biology

    NASA Astrophysics Data System (ADS)

    Maskiewicz, April Lee

    Educational studies report that secondary and college level students have developed only limited understandings of the most basic biological processes and their interrelationships from typical classroom experiences. Furthermore, students have developed undesirable reasoning schemes and beliefs that directly affect how they make sense of and account for biological phenomena. For these reasons, there exists a need to rethink instructional practices in biology. This dissertation discusses how the principles of Harel's (1998, 2001) DNR-based instruction in mathematics could be applied to the teaching and learning of biology. DNR is an acronym for the three foundational principles of the system: Duality, Necessity, and Repeated-reasoning. This study examines the application of these three principles to ecology instruction. Through clinical and teaching interviews, I developed models of students' existing ways of understanding in ecology and inferred their ways of thinking. From these models a hypothetical learning trajectory was developed for 16 college level freshmen enrolled in a 10-week ecology teaching experiment. Through cyclical, interpretive analysis I documented and analyzed the evolution of the participants' progress. The results provide empirical evidence to support the claim that the DNR principles are applicable to ecology instruction. With respect to the Duality Principle, helping students develop specific ways of understanding led to the development of model-based reasoning---a way of thinking and the cognitive objective guiding instruction. Through carefully structured problem solving tasks, the students developed a biological understanding of the relationship between matter cycling, energy flow, and cellular processes such as photosynthesis and respiration, and used this understanding to account for observable phenomena in nature. In the case of intellectual necessity, the results illuminate how problem situations can be developed for biology learners that create cognitive disequilibrium-equilibrium phases and thus lead to modification or refinement of existing schemes. Elements that contributed to creating intellectual need include (a) problem tasks that built on students' existing knowledge; (b) problem tasks that challenged students; (c) a routine in which students presented their group's solution to the class; and (d) the didactical contract (Brousseau, 1997) established in the classroom.

  14. Policy on synthetic biology: deliberation, probability, and the precautionary paradox.

    PubMed

    Wareham, Christopher; Nardini, Cecilia

    2015-02-01

    Synthetic biology is a cutting-edge area of research that holds the promise of unprecedented health benefits. However, in tandem with these large prospective benefits, synthetic biology projects entail a risk of catastrophic consequences whose severity may exceed that of most ordinary human undertakings. This is due to the peculiar nature of synthetic biology as a 'threshold technology' which opens doors to opportunities and applications that are essentially unpredictable. Fears about these potentially unstoppable consequences have led to declarations from civil society groups calling for the use of a precautionary principle to regulate the field. Moreover, the principle is prevalent in law and international agreements. Despite widespread political recognition of a need for caution, the precautionary principle has been extensively criticized as a guide for regulatory policy. We examine a central objection to the principle: that its application entails crippling inaction and incoherence, since whatever action one takes there is always a chance that some highly improbable cataclysm will occur. In response to this difficulty, which we call the 'precautionary paradox,' we outline a deliberative means for arriving at threshold of probability below which potential dangers can be disregarded. In addition, we describe a Bayesian mechanism with which to assign probabilities to harmful outcomes. We argue that these steps resolve the paradox. The rehabilitated PP can thus provide a viable policy option to confront the uncharted waters of synthetic biology research. © 2013 John Wiley & Sons Ltd.

  15. Forthcoming ethical issues in biological psychiatry.

    PubMed

    Helmchen, Hanfried

    2005-01-01

    Ethical issues in biological psychiatry are framed by (i) progress in the neurosciences, and (ii) a changing socio-cultural context. With regard to forthcoming neurotechniques to modify specifically defined brain functions by pharmacological substances with selective effects, by activating neuroplasticity including neurogenesis, or by implantation of neuronal tissues or computer-brain interfaces, etc., ethical problems will develop (i) at the border between therapy of diseases and enhancement of abilities in healthy people with regard to effects on society (e.g., social justice: equal access, loss of societal diversity) as well as on human value systems (e.g., personality, efforts, conditio humana), and (ii) at the border between the medical system and the wellness market with regard to financing what by whom? Ethical dilemmas in psychiatry develop (i) between the individual's best and the common good (demanded from outside medicine), (ii) among different ethical principles (inside medicine), iii) if solutions are influenced by personal reasons without observing ethical principles. Ethical guidelines are necessary for ethical orientation, but may protect against misconduct only (i) if psychiatrists are educated in ethics and (ii) if psychiatric acting is under continuous debate (by ethical review boards or the public). Thus, if we psychiatrists will become ethically sensitive by reflecting and perhaps solving our current ethical dilemmas we will be prepared to deal with forthcoming ethical issues in biological psychiatry.

  16. The "fourth dimension" of gene transcription.

    PubMed

    O'Malley, Bert W

    2009-05-01

    The three dimensions of space provide our relationship to position on the earth, but the fourth dimension of time has an equally profound influence on our lives. Everything from light and sound to weather and biology operate on the principle of measurable temporal periodicity. Consequently, a wide variety of time clocks affect all aspects of our existence. The annual (and biannual) cycles of activity, metabolism, and mating, the monthly physiological clocks of women and men, and the 24-h diurnal rhythms of humans are prime examples. Should it be surprising to us that the fourth dimension also impinges upon gene expression and that the genome itself is regulated by the fastest running of all biological clocks? Recent evidence substantiates the existence of such a ubiquitin-dependent transcriptional clock that is based upon the activation and destruction of transcriptional coactivators.

  17. The “Fourth Dimension” of Gene Transcription

    PubMed Central

    O'Malley, Bert W.

    2009-01-01

    The three dimensions of space provide our relationship to position on the earth, but the fourth dimension of time has an equally profound influence on our lives. Everything from light and sound to weather and biology operate on the principle of measurable temporal periodicity. Consequently, a wide variety of time clocks affect all aspects of our existence. The annual (and biannual) cycles of activity, metabolism, and mating, the monthly physiological clocks of women and men, and the 24-h diurnal rhythms of humans are prime examples. Should it be surprising to us that the fourth dimension also impinges upon gene expression and that the genome itself is regulated by the fastest running of all biological clocks? Recent evidence substantiates the existence of such a ubiquitin-dependent transcriptional clock that is based upon the activation and destruction of transcriptional coactivators. PMID:19221049

  18. EMERGING BIOLOGICAL PRINCIPLES OF METASTASIS

    PubMed Central

    Lambert, Arthur W.; Pattabiraman, Diwakar R.; Weinberg, Robert A.

    2016-01-01

    Metastases account for the great majority of cancer-associated deaths, yet this complex process remains the least understood aspect of cancer biology. As the body of research concerning metastasis continues to grow at a rapid rate, the biological programs that underlie the dissemination and metastatic outgrowth of cancer cells are beginning to come into view. In this review we summarize the cellular and molecular mechanisms involved in metastasis, with a focus on carcinomas where the most is known, and highlight the general principles of metastasis that have begun to emerge. PMID:28187288

  19. Core principles of evolutionary medicine

    PubMed Central

    Grunspan, Daniel Z; Nesse, Randolph M; Barnes, M Elizabeth; Brownell, Sara E

    2018-01-01

    Abstract Background and objectives Evolutionary medicine is a rapidly growing field that uses the principles of evolutionary biology to better understand, prevent and treat disease, and that uses studies of disease to advance basic knowledge in evolutionary biology. Over-arching principles of evolutionary medicine have been described in publications, but our study is the first to systematically elicit core principles from a diverse panel of experts in evolutionary medicine. These principles should be useful to advance recent recommendations made by The Association of American Medical Colleges and the Howard Hughes Medical Institute to make evolutionary thinking a core competency for pre-medical education. Methodology The Delphi method was used to elicit and validate a list of core principles for evolutionary medicine. The study included four surveys administered in sequence to 56 expert panelists. The initial open-ended survey created a list of possible core principles; the three subsequent surveys winnowed the list and assessed the accuracy and importance of each principle. Results Fourteen core principles elicited at least 80% of the panelists to agree or strongly agree that they were important core principles for evolutionary medicine. These principles over-lapped with concepts discussed in other articles discussing key concepts in evolutionary medicine. Conclusions and implications This set of core principles will be helpful for researchers and instructors in evolutionary medicine. We recommend that evolutionary medicine instructors use the list of core principles to construct learning goals. Evolutionary medicine is a young field, so this list of core principles will likely change as the field develops further. PMID:29493660

  20. Core principles of evolutionary medicine: A Delphi study.

    PubMed

    Grunspan, Daniel Z; Nesse, Randolph M; Barnes, M Elizabeth; Brownell, Sara E

    2018-01-01

    Evolutionary medicine is a rapidly growing field that uses the principles of evolutionary biology to better understand, prevent and treat disease, and that uses studies of disease to advance basic knowledge in evolutionary biology. Over-arching principles of evolutionary medicine have been described in publications, but our study is the first to systematically elicit core principles from a diverse panel of experts in evolutionary medicine. These principles should be useful to advance recent recommendations made by The Association of American Medical Colleges and the Howard Hughes Medical Institute to make evolutionary thinking a core competency for pre-medical education. The Delphi method was used to elicit and validate a list of core principles for evolutionary medicine. The study included four surveys administered in sequence to 56 expert panelists. The initial open-ended survey created a list of possible core principles; the three subsequent surveys winnowed the list and assessed the accuracy and importance of each principle. Fourteen core principles elicited at least 80% of the panelists to agree or strongly agree that they were important core principles for evolutionary medicine. These principles over-lapped with concepts discussed in other articles discussing key concepts in evolutionary medicine. This set of core principles will be helpful for researchers and instructors in evolutionary medicine. We recommend that evolutionary medicine instructors use the list of core principles to construct learning goals. Evolutionary medicine is a young field, so this list of core principles will likely change as the field develops further.

  1. Earth's Earliest Ecosystems in the C: The Use of Microbial Mats to Demonstrate General Principles of Scientific Inquiry and Microbial Ecology

    NASA Technical Reports Server (NTRS)

    Bebout, Brad M.; Bucaria, Robin

    2006-01-01

    Microbial mats are living examples of the most ancient biological communities on Earth. As Earth's earliest ecosystems, they are centrally important to understanding the history of life on our planet and are useful models for the search for life elsewhere. As relatively compact (but complete) ecosystems, microbial mats are also extremely useful for educational activities. Mats may be used to demonstrate a wide variety of concepts in general and microbial ecology, including the biogeochemical cycling of elements, photosynthesis and respiration, and the origin of the Earth's present oxygen containing atmosphere. Microbial mats can be found in a number of common environments accessible to teachers, and laboratory microbial mats can be constructed using materials purchased from biological supply houses. With funding from NASA's Exobiology program, we have developed curriculum and web-based activities centered on the use of microbial mats as tools for demonstrating general principles in ecology, and the scientific process. Our web site (http://microbes.arc.nasa.gov) includes reference materials, lesson plans, and a "Web Lab", featuring living mats maintained in a mini-aquarium. The site also provides information as to how research on microbial mats supports NASA's goals, and various NASA missions. A photo gallery contains images of mats, microscopic views of the organisms that form them, and our own research activities. An animated educational video on the web site uses computer graphic and video microscopy to take students on a journey into a microbial mat. These activities are targeted to a middle school audience and are aligned with the National Science Standards.

  2. Implementing Recommendations for Introductory Biology by Writing a New Textbook

    ERIC Educational Resources Information Center

    Barsoum, Mark J.; Sellers, Patrick J.; Campbell, A. Malcolm; Heyer, Laurie J.; Paradise, Christopher J.

    2013-01-01

    We redesigned the undergraduate introductory biology course by writing a new textbook ("Integrating Concepts in Biology" ["ICB"]) that follows first principles of learning. Our approach emphasizes primary data interpretation and the utility of mathematics in biology, while de-emphasizing memorization. This redesign divides biology into five big…

  3. Systemic Effects of Non-Endocrine Tumours

    PubMed Central

    Sullivan, James D.; Rona, George

    1964-01-01

    Tumours of non-endocrine origin may exert deleterious effects by elaborating active principles which disturb body regulation. Systemic manifestations are fairly common with neoplasms of the lung, kidney, gastro-intestinal tract and thymus. The secretion of these tumours may have a known chemical structure (serotonin), may present hormone-like action (parathormone, antidiuretic hormone, insulinoid), or have well-defined biological properties (erythropoietin, gastrin-like principle). Tumours may stimulate endocrine glands by an unknown mechanism, producing disorders such as Cushing's syndrome, hypercalcemia, gynecomastia and hypoglycemia. Thymomas may be associated with autoimmune diseases. Tumours may extensively utilize or excrete some metabolite (glucose) or electrolyte (Na or K). Awareness of the systemic effects of various neoplasms may lead to an early diagnosis and proper treatment of these manifestations. PMID:14204555

  4. The Ferguson principle and an analysis of biological activity of gases and vapors.

    PubMed

    Abraham, M H; Nielsen, G D; Alarie, Y

    1994-05-01

    The Ferguson principle, that Pnar/PO (Pnar is the partial pressure of a series of compounds giving rise to a particular effect on a given system by a physical mechanism, and PO is the saturated vapor pressure of the liquid narcotic) is constant for a series of nonreactive narcotics or toxicants in a given system, is examined and shown to have no thermodynamic basis, contrary to the position of Brink and Posternak. Conditions under which Pnar/PO might be expected to be roughly constant, as an empirical observation, are set out and it is shown that such an observation is consistent with a receptor area in which the liquid narcotic solubilities are roughly constant. An interpretation of relationships between agonist descriptors and biological effects is carried out with three simple biological models. It is shown that the biological potency of nonreactive gases and vapors can be controlled either by an equilibrium between the agonist in the gas phase and the agonist in a receptor or by an equilibrium between the agonist in the gas phase and the agonist in a receptor phase. It is further shown that with the solvation equation of Abraham, solvents can be chosen that mimic the chemical properties of the receptor or receptor phase. For the example of upper respiratory tract irritation of male Swiss OF1 mice, such solvents include N-formylmorpholine, a trialkylphosphate, and wet octanol, but not water itself.

  5. Assessing sub-Saharan Erythrina for efficacy: traditional uses, biological activities and phytochemistry.

    PubMed

    Kone, Witabouna Mamidou; Solange, Kakou-Ngazoa E; Dosso, Mireille

    2011-05-15

    The genus Erythrina comprises more than 100 species, widely distributed in tropical and subtropical areas. In Africa, 31 wild species and 14 cultivated species have been described. In sub-Saharan Africa, Erythrina species are used to treat frequent parasitic and microbial diseases, inflammation, cancer, wounds. The rationale of these traditional uses in African traditional medicine was established by screening several species for biological activities. Promising activities were found against bacteria, parasites (Plasmodium), human and phytopathogenic fungi, some of which were multidrug resistant (MDR) micro organisms. Some species also exhibited antioxidant, anti-inflammatory activities and enzymes inhibitory properties. Most of the species chemically investigated were reported to contain flavanones, prenylated isoflavones, isoflavanones and pterocarpans. Some phytochemicals (vogelin B, vogelin C, isowightcone, abyssinin II, derrone) were the active principles as antibacterials, antifungals, antiplasmodials and inhibitors of enzyme borne diseases (PTP1B, HIV protease, DGAT). This review highlights the important role of Erythrina species as sources of lead compounds or new class of phytotherapeutic agents for fighting against major public health (MDR infections, cancer, diabetes, obesity) in sub-Saharan Africa.

  6. Self-organization principles of intracellular pattern formation.

    PubMed

    Halatek, J; Brauns, F; Frey, E

    2018-05-26

    Dynamic patterning of specific proteins is essential for the spatio-temporal regulation of many important intracellular processes in prokaryotes, eukaryotes and multicellular organisms. The emergence of patterns generated by interactions of diffusing proteins is a paradigmatic example for self-organization. In this article, we review quantitative models for intracellular Min protein patterns in Escherichia coli , Cdc42 polarization in Saccharomyces cerevisiae and the bipolar PAR protein patterns found in Caenorhabditis elegans By analysing the molecular processes driving these systems we derive a theoretical perspective on general principles underlying self-organized pattern formation. We argue that intracellular pattern formation is not captured by concepts such as 'activators', 'inhibitors' or 'substrate depletion'. Instead, intracellular pattern formation is based on the redistribution of proteins by cytosolic diffusion, and the cycling of proteins between distinct conformational states. Therefore, mass-conserving reaction-diffusion equations provide the most appropriate framework to study intracellular pattern formation. We conclude that directed transport, e.g. cytosolic diffusion along an actively maintained cytosolic gradient, is the key process underlying pattern formation. Thus the basic principle of self-organization is the establishment and maintenance of directed transport by intracellular protein dynamics.This article is part of the theme issue 'Self-organization in cell biology'. © 2018 The Authors.

  7. Biophysical principles of regulatory action of low-intensity laser irradiation

    NASA Astrophysics Data System (ADS)

    Mostovnikov, Vasili A.; Mostovnikova, Galina R.; Plavski, Vitali Y.; Plavskaja, Ljudmila G.

    1996-01-01

    The investigations carried out in our group on biological systems of various organization level (enzyme molecules in solution, human and animal cell cultures), allowed us to conclude, that the light-induced changes of spatial structure of cells components form the basis of biological activity (and as a consequence therapeutic effect) of various wavelength low-intensity laser emission. Photophysical mechanism of these changes lies in the reorientation of highregulated anisotropic parts (domains) with the liquid-crystalline type of ordering of the cell components due to the interaction between the electric field and the light induced integral electric dipole of the domain. The mechanism of such reorientation is well established in physics of liquid crystals of nematic type and is known as light induced analogue of Frederix's effect. The following results enable us to draw the conclusion about the determining role of the orientations effects on the biological activity mechanism of low-intensity laser radiation: (1) the possibility of reversible modification of spatial structure and enzyme molecules functional activity under the influence of laser radiation outside the band of their own or admixture absorption; (2) the dependence of biological effect of laser radiation on the functional activity of cells vs. polarization degree of the light with the maximum photobiological effects observed for linear-polarized radiation; (3) the equivalence of a static magnetic field and low-intensity laser radiation in action on functional activity of the cells and the lowering of the laser field intensity for the achieving the definite changes of the cell functional activity in the presence of static magnetic field.

  8. Active learning in the lecture theatre using 3D printed objects.

    PubMed

    Smith, David P

    2016-01-01

    The ability to conceptualize 3D shapes is central to understanding biological processes. The concept that the structure of a biological molecule leads to function is a core principle of the biochemical field. Visualisation of biological molecules often involves vocal explanations or the use of two dimensional slides and video presentations. A deeper understanding of these molecules can however be obtained by the handling of objects. 3D printed biological molecules can be used as active learning tools to stimulate engagement in large group lectures. These models can be used to build upon initial core knowledge which can be delivered in either a flipped form or a more didactic manner. Within the teaching session the students are able to learn by handling, rotating and viewing the objects to gain an appreciation, for example, of an enzyme's active site or the difference between the major and minor groove of DNA. Models and other artefacts can be handled in small groups within a lecture theatre and act as a focal point to generate conversation. Through the approach presented here core knowledge is first established and then supplemented with high level problem solving through a "Think-Pair-Share" cooperative learning strategy. The teaching delivery was adjusted based around experiential learning activities by moving the object from mental cognition and into the physical environment. This approach led to students being able to better visualise biological molecules and a positive engagement in the lecture. The use of objects in teaching allows the lecturer to create interactive sessions that both challenge and enable the student.

  9. Active learning in the lecture theatre using 3D printed objects

    PubMed Central

    Smith, David P.

    2016-01-01

    The ability to conceptualize 3D shapes is central to understanding biological processes. The concept that the structure of a biological molecule leads to function is a core principle of the biochemical field. Visualisation of biological molecules often involves vocal explanations or the use of two dimensional slides and video presentations. A deeper understanding of these molecules can however be obtained by the handling of objects. 3D printed biological molecules can be used as active learning tools to stimulate engagement in large group lectures. These models can be used to build upon initial core knowledge which can be delivered in either a flipped form or a more didactic manner. Within the teaching session the students are able to learn by handling, rotating and viewing the objects to gain an appreciation, for example, of an enzyme’s active site or the difference between the major and minor groove of DNA. Models and other artefacts can be handled in small groups within a lecture theatre and act as a focal point to generate conversation. Through the approach presented here core knowledge is first established and then supplemented with high level problem solving through a "Think-Pair-Share" cooperative learning strategy. The teaching delivery was adjusted based around experiential learning activities by moving the object from mental cognition and into the physical environment. This approach led to students being able to better visualise biological molecules and a positive engagement in the lecture. The use of objects in teaching allows the lecturer to create interactive sessions that both challenge and enable the student. PMID:27366318

  10. Ethical Principles: Guiding the Use of Animals in Research.

    ERIC Educational Resources Information Center

    Morrison, Adrian R.

    2003-01-01

    Presents arguments on the use of animals in biological and medical research. Discusses ethical considerations, principles, and animal rights in scientific research. (Contains 21 references.) (Author/YDS)

  11. An ecological basis for ecosystem management

    Treesearch

    M. R. Kaufmann; R. T. Graham; D. A. Boyce; W. H. Moir; L. Perry; R. T. Reynolds; R. L. Bassett; P. Mehlhop; C. B. Edminster; W. M. Block; P. S. Corn

    1994-01-01

    Guiding principles based on conservation biology are applied in assessing ecosystem needs. Ecosystem, economic, and social needs are integrated in a decision model in which the guiding principles are used as a primary filter for evaluating proposed actions. Management practices consistent with the guiding principles are likely to lead to ecological, economic, and...

  12. Progressive Education Standards: A Neuroscience Framework

    ERIC Educational Resources Information Center

    O'Grady, Patty

    2011-01-01

    This paper proposes a coherent and unique set of 12 standards, adopting a neuroscience framework for biologically based on school reform. This model of educational principles and practices aligns with the long-standing principles and practices of the Progressive Education Movement in the United States and the emerging principles of neuroscience.…

  13. Optimality Principles in the Regulation of Metabolic Networks

    PubMed Central

    Berkhout, Jan; Bruggeman, Frank J.; Teusink, Bas

    2012-01-01

    One of the challenging tasks in systems biology is to understand how molecular networks give rise to emergent functionality and whether universal design principles apply to molecular networks. To achieve this, the biophysical, evolutionary and physiological constraints that act on those networks need to be identified in addition to the characterisation of the molecular components and interactions. Then, the cellular “task” of the network—its function—should be identified. A network contributes to organismal fitness through its function. The premise is that the same functions are often implemented in different organisms by the same type of network; hence, the concept of design principles. In biology, due to the strong forces of selective pressure and natural selection, network functions can often be understood as the outcome of fitness optimisation. The hypothesis of fitness optimisation to understand the design of a network has proven to be a powerful strategy. Here, we outline the use of several optimisation principles applied to biological networks, with an emphasis on metabolic regulatory networks. We discuss the different objective functions and constraints that are considered and the kind of understanding that they provide. PMID:24957646

  14. Optimality principles in the regulation of metabolic networks.

    PubMed

    Berkhout, Jan; Bruggeman, Frank J; Teusink, Bas

    2012-08-29

    One of the challenging tasks in systems biology is to understand how molecular networks give rise to emergent functionality and whether universal design principles apply to molecular networks. To achieve this, the biophysical, evolutionary and physiological constraints that act on those networks need to be identified in addition to the characterisation of the molecular components and interactions. Then, the cellular "task" of the network-its function-should be identified. A network contributes to organismal fitness through its function. The premise is that the same functions are often implemented in different organisms by the same type of network; hence, the concept of design principles. In biology, due to the strong forces of selective pressure and natural selection, network functions can often be understood as the outcome of fitness optimisation. The hypothesis of fitness optimisation to understand the design of a network has proven to be a powerful strategy. Here, we outline the use of several optimisation principles applied to biological networks, with an emphasis on metabolic regulatory networks. We discuss the different objective functions and constraints that are considered and the kind of understanding that they provide.

  15. New Frontiers and Challenges for Single-Cell Electrochemical Analysis.

    PubMed

    Zhang, Jingjing; Zhou, Junyu; Pan, Rongrong; Jiang, Dechen; Burgess, James D; Chen, Hong-Yuan

    2018-02-23

    Previous measurements of cell populations might obscure many important cellular differences, and new strategies for single-cell analyses are urgently needed to re-examine these fundamental biological principles for better diagnosis and treatment of diseases. Electrochemistry is a robust technique for the analysis of single living cells that has the advantages of minor interruption of cellular activity and provides the capability of high spatiotemporal resolution. The achievements of the past 30 years have revealed significant information about the exocytotic events of single cells to elucidate the mechanisms of cellular activity. Currently, the rapid developments of micro/nanofabrication and optoelectronic technologies drive the development of multifunctional electrodes and novel electrochemical approaches with higher resolution for single cells. In this Perspective, three new frontiers in this field, namely, electrochemical microscopy, intracellular analysis, and single-cell analysis in a biological system (i.e., neocortex and retina), are reviewed. The unique features and remaining challenges of these techniques are discussed.

  16. Light Activated Cell Migration in Synthetic Extracellular Matrices

    PubMed Central

    Guo, Qiongyu; Wang, Xiaobo; Tibbitt, Mark W.; Anseth, Kristi S.; Montell, Denise J.; Elisseeff, Jennifer H.

    2012-01-01

    Synthetic extracellular matrices provide a framework in which cells can be exposed to defined physical and biological cues. However no method exists to manipulate single cells within these matrices. It is desirable to develop such methods in order to understand fundamental principles of cell migration and define conditions that support or inhibit cell movement within these matrices. Here, we present a strategy for manipulating individual mammalian stem cells in defined synthetic hydrogels through selective optical activation of Rac, which is an intracellular signaling protein that plays a key role in cell migration. Photoactivated cell migration in synthetic hydrogels depended on mechanical and biological cues in the biomaterial. Real-time hydrogel photodegradation was employed to create geometrically defined channels and spaces in which cells could be photoactivated to migrate. Cell migration speed was significantly higher in the photo-etched channels and cells could easily change direction of movement compared to the bulk hydrogels. PMID:22889487

  17. Modeling place field activity with hierarchical slow feature analysis

    PubMed Central

    Schönfeld, Fabian; Wiskott, Laurenz

    2015-01-01

    What are the computational laws of hippocampal activity? In this paper we argue for the slowness principle as a fundamental processing paradigm behind hippocampal place cell firing. We present six different studies from the experimental literature, performed with real-life rats, that we replicated in computer simulations. Each of the chosen studies allows rodents to develop stable place fields and then examines a distinct property of the established spatial encoding: adaptation to cue relocation and removal; directional dependent firing in the linear track and open field; and morphing and scaling the environment itself. Simulations are based on a hierarchical Slow Feature Analysis (SFA) network topped by a principal component analysis (ICA) output layer. The slowness principle is shown to account for the main findings of the presented experimental studies. The SFA network generates its responses using raw visual input only, which adds to its biological plausibility but requires experiments performed in light conditions. Future iterations of the model will thus have to incorporate additional information, such as path integration and grid cell activity, in order to be able to also replicate studies that take place during darkness. PMID:26052279

  18. A brief historical perspective on the advent of brain oscillations in the biological and psychological disciplines.

    PubMed

    Karakaş, Sirel; Barry, Robert J

    2017-04-01

    We aim to review the historical evolution that has led to the study of the brain (body)-mind relationship based on brain oscillations, to outline and illustrate the principles of neuro-oscillatory dynamics using research findings. The paper addresses the relevant developments in behavioral sciences after Wundt established the science of psychology, and developments in the neurosciences after alpha and gamma oscillations were discovered by Berger and Adrian, respectively. Basic neuroscientific studies have led to a number of principles: (1) spontaneous EEG is composed of a set of oscillatory components, (2) the brain responds with oscillatory activity, (3) poststimulus oscillatory activity is a function of prestimulus activity, (4) the brain response results from a superposition of oscillatory components, (5) there are multiplicities with regard to oscillations and functions, and (6) oscillations are spatially integrated. Findings of clinical studies suggest that oscillatory responses can serve as biomarkers for neuropsychiatric disorders. However, the field of psychology is still making limited use of neuro-oscillatory dynamics for a bio-behavioral understanding of cognitive-affective processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Essential chemistry for biochemists

    PubMed Central

    Jonsson, Amanda L.; Roberts, Mark A.J.; Kiappes, J.L.; Scott, Kathryn A.

    2017-01-01

    Within every living organism, countless reactions occur every second. These reactions typically occur more rapidly and with greater efficiency than would be possible under the same conditions in the chemical laboratory, and while using only the subset of elements that are readily available in nature. Despite these apparent differences between life and the laboratory, biological reactions are governed by the same rules as any other chemical reaction. Thus, a firm understanding of the fundamentals of chemistry is invaluable in biochemistry. There are entire textbooks devoted to the application of chemical principles in biological systems and so it is not possible to cover all of the relevant topics in depth in this short article. The aim is instead to provide a brief overview of those areas in chemistry that are most relevant to biochemistry. We summarize the basic principles, give examples of how these principles are applied in biological systems and suggest further reading on individual topics. PMID:28951470

  20. Our Selections and Decisions: Inherent Features of the Nervous System?

    NASA Astrophysics Data System (ADS)

    Rösler, Frank

    The chapter summarizes findings on the neuronal bases of decisionmaking. Taking the phenomenon of selection it will be explained that systems built only from excitatory and inhibitory neuron (populations) have the emergent property of selecting between different alternatives. These considerations suggest that there exists a hierarchical architecture with central selection switches. However, in such a system, functions of selection and decision-making are not localized, but rather emerge from an interaction of several participating networks. These are, on the one hand, networks that process specific input and output representations and, on the other hand, networks that regulate the relative activation/inhibition of the specific input and output networks. These ideas are supported by recent empirical evidence. Moreover, other studies show that rather complex psychological variables, like subjective probability estimates, expected gains and losses, prediction errors, etc., do have biological correlates, i.e., they can be localized in time and space as activation states of neural networks and single cells. These findings suggest that selections and decisions are consequences of an architecture which, seen from a biological perspective, is fully deterministic. However, a transposition of such nomothetic functional principles into the idiographic domain, i.e., using them as elements for comprehensive 'mechanistic' explanations of individual decisions, seems not to be possible because of principle limitations. Therefore, individual decisions will remain predictable by means of probabilistic models alone.

  1. Using a Replica of Leeuwenhoek's Microscope to Teach the History of Science and to Motivate Students to Discover the Vision and the Contributions of the First Microscopists

    PubMed Central

    Loreto, Elgion L.S.; Rocha, João B.T.

    2009-01-01

    The history of science should be incorporated into science teaching as a means of improving learning and also to increase the students' understanding about the nature of science. In biology education, the history of microscopy deserves a special place. The discovery of this instrument not only opened a new and fantastic microworld but also led to the development of one unifying principle of biological sciences (i.e., cell theory). The microscopes of Leeuwenhoek and Hooke opened windows into the microworld of living organisms. In the present work, the knowledge of these themes was analyzed in a group of students beginning an undergraduate biology course. Our data suggest that the history of microscopy is poorly treated at the secondary school level. We propose a didactic activity using a replica of Leeuwenhoek's microscope made with Plexiglas and a lens obtained from a key chain laser pointer or from a broken CD drive. The proposed activity motivated students to learn about microscopy and helped them to appreciate scientific knowledge from a historical perspective. PMID:19952102

  2. Using a replica of Leeuwenhoek's microscope to teach the history of science and to motivate students to discover the vision and the contributions of the first microscopists.

    PubMed

    Sepel, Lenira M N; Loreto, Elgion L S; Rocha, João B T

    2009-01-01

    The history of science should be incorporated into science teaching as a means of improving learning and also to increase the students' understanding about the nature of science. In biology education, the history of microscopy deserves a special place. The discovery of this instrument not only opened a new and fantastic microworld but also led to the development of one unifying principle of biological sciences (i.e., cell theory). The microscopes of Leeuwenhoek and Hooke opened windows into the microworld of living organisms. In the present work, the knowledge of these themes was analyzed in a group of students beginning an undergraduate biology course. Our data suggest that the history of microscopy is poorly treated at the secondary school level. We propose a didactic activity using a replica of Leeuwenhoek's microscope made with Plexiglas and a lens obtained from a key chain laser pointer or from a broken CD drive. The proposed activity motivated students to learn about microscopy and helped them to appreciate scientific knowledge from a historical perspective.

  3. Adverse outcome pathway (AOP) development I: Strategies and principles

    EPA Science Inventory

    An adverse outcome pathway (AOP) is a conceptual framework that organizes existing knowledge concerning biologically plausible, and empirically-supported, links between molecular-level perturbation of a biological system and an adverse outcome at a level of biological organizatio...

  4. In search of the Golden Fleece: Unraveling principles of morphogenesis by studying the integrative biology of skin appendages

    PubMed Central

    Hughes, Michael W.; Wu, Ping; Jiang, Ting-Xin; Lin, Sung-Jan; Dong, Chen-Yuan; Li, Ang; Hsieh, Fon-Jou; Widelitz, Randall B.; Choung, Cheng Ming

    2013-01-01

    Summary The mythological story of the Golden Fleece symbolizes the magical regenerative power of skin appendages. Similar to the adventurous pursuit of the Golden Fleece by the multi-talented Argonauts, today we also need an integrated multi-disciplined approach to understand the cellular and molecular processes during development, regeneration and evolution of skin appendages. To this end, we have explored several aspects of skin appendage biology that contribute to the Turing activator / inhibitor model in feather pattern formation, the topo-biological arrangement of stem cells in organ shape determination, the macro-environmental regulation of stem cells in regenerative hair waves, and potential novel molecular pathways in the morphological evolution of feathers. Here we show our current integrative biology efforts to unravel the complex cellular behavior in patterning stem cells and the control of regional specificity in skin appendages. We use feather / scale tissue recombination to demonstrate the timing control of competence and inducibility. Feathers from different body regions are used to study skin regional specificity. Bioinformatic analyses of transcriptome microarrays show the potential involvement of candidate molecular pathways. We further show Hox genes exhibit some region specific expression patterns. To visualize real time events, we applied time-lapse movies, confocal microscopy and multiphoton microscopy to analyze the morphogenesis of cultured embryonic chicken skin explants. These modern imaging technologies reveal unexpectedly complex cellular flow and organization of extracellular matrix molecules in three dimensions. While these approaches are in preliminary stages, this perspective highlights the challenges we face and new integrative tools we will use. Future work will follow these leads to develop a systems biology view and understanding in the morphogenetic principles that govern the development and regeneration of ectodermal organs. PMID:21437328

  5. A Powerful Toolkit for Synthetic Biology: Over 3.8 Billion Years of Evolution

    NASA Technical Reports Server (NTRS)

    Rothschild, Lynn J.

    2010-01-01

    The combination of evolutionary with engineering principles will enhance synthetic biology. Conversely, synthetic biology has the potential to enrich evolutionary biology by explaining why some adaptive space is empty, on Earth or elsewhere. Synthetic biology, the design and construction of artificial biological systems, substitutes bio-engineering for evolution, which is seen as an obstacle. But because evolution has produced the complexity and diversity of life, it provides a proven toolkit of genetic materials and principles available to synthetic biology. Evolution operates on the population level, with the populations composed of unique individuals that are historical entities. The source of genetic novelty includes mutation, gene regulation, sex, symbiosis, and interspecies gene transfer. At a phenotypic level, variation derives from regulatory control, replication and diversification of components, compartmentalization, sexual selection and speciation, among others. Variation is limited by physical constraints such as diffusion, and chemical constraints such as reaction rates and membrane fluidity. While some of these tools of evolution are currently in use in synthetic biology, all ought to be examined for utility. A hybrid approach of synthetic biology coupled with fine-tuning through evolution is suggested

  6. A powerful toolkit for synthetic biology: Over 3.8 billion years of evolution.

    PubMed

    Rothschild, Lynn J

    2010-04-01

    The combination of evolutionary with engineering principles will enhance synthetic biology. Conversely, synthetic biology has the potential to enrich evolutionary biology by explaining why some adaptive space is empty, on Earth or elsewhere. Synthetic biology, the design and construction of artificial biological systems, substitutes bio-engineering for evolution, which is seen as an obstacle. But because evolution has produced the complexity and diversity of life, it provides a proven toolkit of genetic materials and principles available to synthetic biology. Evolution operates on the population level, with the populations composed of unique individuals that are historical entities. The source of genetic novelty includes mutation, gene regulation, sex, symbiosis, and interspecies gene transfer. At a phenotypic level, variation derives from regulatory control, replication and diversification of components, compartmentalization, sexual selection and speciation, among others. Variation is limited by physical constraints such as diffusion, and chemical constraints such as reaction rates and membrane fluidity. While some of these tools of evolution are currently in use in synthetic biology, all ought to be examined for utility. A hybrid approach of synthetic biology coupled with fine-tuning through evolution is suggested.

  7. Training Excitatory-Inhibitory Recurrent Neural Networks for Cognitive Tasks: A Simple and Flexible Framework

    PubMed Central

    Wang, Xiao-Jing

    2016-01-01

    The ability to simultaneously record from large numbers of neurons in behaving animals has ushered in a new era for the study of the neural circuit mechanisms underlying cognitive functions. One promising approach to uncovering the dynamical and computational principles governing population responses is to analyze model recurrent neural networks (RNNs) that have been optimized to perform the same tasks as behaving animals. Because the optimization of network parameters specifies the desired output but not the manner in which to achieve this output, “trained” networks serve as a source of mechanistic hypotheses and a testing ground for data analyses that link neural computation to behavior. Complete access to the activity and connectivity of the circuit, and the ability to manipulate them arbitrarily, make trained networks a convenient proxy for biological circuits and a valuable platform for theoretical investigation. However, existing RNNs lack basic biological features such as the distinction between excitatory and inhibitory units (Dale’s principle), which are essential if RNNs are to provide insights into the operation of biological circuits. Moreover, trained networks can achieve the same behavioral performance but differ substantially in their structure and dynamics, highlighting the need for a simple and flexible framework for the exploratory training of RNNs. Here, we describe a framework for gradient descent-based training of excitatory-inhibitory RNNs that can incorporate a variety of biological knowledge. We provide an implementation based on the machine learning library Theano, whose automatic differentiation capabilities facilitate modifications and extensions. We validate this framework by applying it to well-known experimental paradigms such as perceptual decision-making, context-dependent integration, multisensory integration, parametric working memory, and motor sequence generation. Our results demonstrate the wide range of neural activity patterns and behavior that can be modeled, and suggest a unified setting in which diverse cognitive computations and mechanisms can be studied. PMID:26928718

  8. "Dissection" of a Hair Dryer

    ERIC Educational Resources Information Center

    Eisenstein, Stan; Simpson, Jeff

    2008-01-01

    The electrical design of the common hair dryer is based almost entirely on relatively simple principles learned in introductory physics classes. Just as biology students dissect a frog to see the principles of anatomy in action, physics students can "dissect" a hair dryer to see how principles of electricity are used in a real system. They can…

  9. Design principles of nuclear receptor signaling: how complex networking improves signal transduction

    PubMed Central

    Kolodkin, Alexey N; Bruggeman, Frank J; Plant, Nick; Moné, Martijn J; Bakker, Barbara M; Campbell, Moray J; van Leeuwen, Johannes P T M; Carlberg, Carsten; Snoep, Jacky L; Westerhoff, Hans V

    2010-01-01

    The topology of nuclear receptor (NR) signaling is captured in a systems biological graphical notation. This enables us to identify a number of ‘design' aspects of the topology of these networks that might appear unnecessarily complex or even functionally paradoxical. In realistic kinetic models of increasing complexity, calculations show how these features correspond to potentially important design principles, e.g.: (i) cytosolic ‘nuclear' receptor may shuttle signal molecules to the nucleus, (ii) the active export of NRs may ensure that there is sufficient receptor protein to capture ligand at the cytoplasmic membrane, (iii) a three conveyor belts design dissipating GTP-free energy, greatly aids response, (iv) the active export of importins may prevent sequestration of NRs by importins in the nucleus and (v) the unspecific nature of the nuclear pore may ensure signal-flux robustness. In addition, the models developed are suitable for implementation in specific cases of NR-mediated signaling, to predict individual receptor functions and differential sensitivity toward physiological and pharmacological ligands. PMID:21179018

  10. WORKSHOP ON APPLICATION OF STATISTICAL METHODS TO BIOLOGICALLY-BASED PHARMACOKINETIC MODELING FOR RISK ASSESSMENT

    EPA Science Inventory

    Biologically-based pharmacokinetic models are being increasingly used in the risk assessment of environmental chemicals. These models are based on biological, mathematical, statistical and engineering principles. Their potential uses in risk assessment include extrapolation betwe...

  11. Engineering for the 21st century: synthetic biology.

    PubMed

    Munnelly, Kevin

    2013-05-17

    For years, scientists have hoped that biology would find its engineering counterpart--a series of principles that could be used as reliably as chemical engineering is for chemistry. Thanks to major advances in synthetic biology, those hopes may soon be realized.

  12. Biological robustness.

    PubMed

    Kitano, Hiroaki

    2004-11-01

    Robustness is a ubiquitously observed property of biological systems. It is considered to be a fundamental feature of complex evolvable systems. It is attained by several underlying principles that are universal to both biological organisms and sophisticated engineering systems. Robustness facilitates evolvability and robust traits are often selected by evolution. Such a mutually beneficial process is made possible by specific architectural features observed in robust systems. But there are trade-offs between robustness, fragility, performance and resource demands, which explain system behaviour, including the patterns of failure. Insights into inherent properties of robust systems will provide us with a better understanding of complex diseases and a guiding principle for therapy design.

  13. Recent developments in the field of arrow and dart poisons.

    PubMed

    Philippe, Geneviève; Angenot, Luc

    2005-08-22

    Arrow and dart poisons, considered as conventional natural sources for future drug discovery, have already provided numerous biologically active molecules used as drugs in therapeutic applications or in pharmacological research. Plants containing alkaloids or cardiotonic glycosides have generally been the main ingredients responsible for the efficacy of these poisons, although some animals, such as frogs, have also been employed. This paper, without being exhaustive, reports the greater strides made during the past 15 years in the understanding of the chemical nature and biological properties of arrow and dart poison constituents. Examples both of promising biological properties shown by these molecules and of crucial discoveries achieved by their use as pharmacological tools are given. Further studies of these toxic principles are likely to enable scientists to find new valuable lead compounds, useful in many fields of research, like oncology, inflammation and infectious diseases.

  14. Aminoglycosides: Molecular Insights on the Recognition of RNA and Aminoglycoside Mimics

    PubMed Central

    Chittapragada, Maruthi; Roberts, Sarah; Ham, Young Wan

    2009-01-01

    RNA is increasingly recognized for its significant functions in biological systems and has recently become an important molecular target for therapeutics development. Aminoglycosides, a large class of clinically significant antibiotics, exert their biological functions by binding to prokaryotic ribosomal RNA (rRNA) and interfering with protein translation, resulting in bacterial cell death. They are also known to bind to viral mRNAs such as HIV-1 RRE and TAR. Consequently, aminoglycosides are accepted as the single most important model in understanding the principles that govern small molecule-RNA recognition, which is essential for the development of novel antibacterial, antiviral or even anti-oncogenic agents. This review outlines the chemical structures and mechanisms of molecular recognition and antibacterial activity of aminoglycosides and various aminoglycoside mimics that have recently been devised to improve biological efficacy, binding affinity and selectivity, or to circumvent bacterial resistance. PMID:19812740

  15. Sulfonylureas and Glinides as New PPARγ Agonists:. Virtual Screening and Biological Assays

    NASA Astrophysics Data System (ADS)

    Scarsi, Marco; Podvinec, Michael; Roth, Adrian; Hug, Hubert; Kersten, Sander; Albrecht, Hugo; Schwede, Torsten; Meyer, Urs A.; Rücker, Christoph

    2007-12-01

    This work combines the predictive power of computational drug discovery with experimental validation by means of biological assays. In this way, a new mode of action for type 2 diabetes drugs has been unvealed. Most drugs currently employed in the treatment of type 2 diabetes either target the sulfonylurea receptor stimulating insulin release (sulfonylureas, glinides), or target PPARγ improving insulin resistance (thiazolidinediones). Our work shows that sulfonylureas and glinides bind to PPARγ and exhibit PPARγ agonistic activity. This result was predicted in silico by virtual screening and confirmed in vitro by three biological assays. This dual mode of action of sulfonylureas and glinides may open new perspectives for the molecular pharmacology of antidiabetic drugs, since it provides evidence that drugs can be designed which target both the sulfonylurea receptor and PPARγ. Targeting both receptors could in principle allow to increase pancreatic insulin secretion, as well as to improve insulin resistance.

  16. Kirigami artificial muscles with complex biologically inspired morphologies

    NASA Astrophysics Data System (ADS)

    Sareh, Sina; Rossiter, Jonathan

    2013-01-01

    In this paper we present bio-inspired smart structures which exploit the actuation of flexible ionic polymer composites and the kirigami design principle. Kirigami design is used to convert planar actuators into active 3D structures capable of large out-of-plane displacement and that replicate biological mechanisms. Here we present the burstbot, a fluid control and propulsion mechanism based on the atrioventricular cuspid valve, and the vortibot, a spiral actuator based on Vorticella campanula, a ciliate protozoa. Models derived from biological counterparts are used as a platform for design optimization and actuator performance measurement. The symmetric and asymmetric fluid interactions of the burstbot are investigated and the effectiveness in fluid transport applications is demonstrated. The vortibot actuator is geometrically optimized as a camera positioner capable of 360° scanning. Experimental results for a one-turn spiral actuator show complex actuation derived from a single degree of freedom control signal.

  17. ENVIRONMENTAL HYDRAULICS

    EPA Science Inventory

    The thermal, chemical, and biological quality of water in rivers, lakes, reservoirs, and near coastal areas is inseparable from a consideration of hydraulic engineering principles: therefore, the term environmental hydraulics. In this chapter we discuss the basic principles of w...

  18. Team-Teaching a Current Events-Based Biology Course for Nonmajors

    ERIC Educational Resources Information Center

    Bondos, Sarah E.; Phillips, Dereth

    2008-01-01

    Rice University has created a team-taught interactive biology course for nonmajors with a focus on cutting edge biology in the news--advances in biotechnology, medicine, and science policy, along with the biological principles and methodology upon which these advances are based. The challenges inherent to teaching current topics were minimized by…

  19. SPR Biosensors in Direct Molecular Fishing: Implications for Protein Interactomics.

    PubMed

    Florinskaya, Anna; Ershov, Pavel; Mezentsev, Yuri; Kaluzhskiy, Leonid; Yablokov, Evgeniy; Medvedev, Alexei; Ivanov, Alexis

    2018-05-18

    We have developed an original experimental approach based on the use of surface plasmon resonance (SPR) biosensors, applicable for investigation of potential partners involved in protein⁻protein interactions (PPI) as well as protein⁻peptide or protein⁻small molecule interactions. It is based on combining a SPR biosensor, size exclusion chromatography (SEC), mass spectrometric identification of proteins (LC-MS/MS) and direct molecular fishing employing principles of affinity chromatography for isolation of potential partner proteins from the total lysate of biological samples using immobilized target proteins (or small non-peptide compounds) as ligands. Applicability of this approach has been demonstrated within the frame of the Human Proteome Project (HPP) and PPI regulation by a small non-peptide biologically active compound, isatin.

  20. Quantum probability ranking principle for ligand-based virtual screening.

    PubMed

    Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal

    2017-04-01

    Chemical libraries contain thousands of compounds that need screening, which increases the need for computational methods that can rank or prioritize compounds. The tools of virtual screening are widely exploited to enhance the cost effectiveness of lead drug discovery programs by ranking chemical compounds databases in decreasing probability of biological activity based upon probability ranking principle (PRP). In this paper, we developed a novel ranking approach for molecular compounds inspired by quantum mechanics, called quantum probability ranking principle (QPRP). The QPRP ranking criteria would make an attempt to draw an analogy between the physical experiment and molecular structure ranking process for 2D fingerprints in ligand based virtual screening (LBVS). The development of QPRP criteria in LBVS has employed the concepts of quantum at three different levels, firstly at representation level, this model makes an effort to develop a new framework of molecular representation by connecting the molecular compounds with mathematical quantum space. Secondly, estimate the similarity between chemical libraries and references based on quantum-based similarity searching method. Finally, rank the molecules using QPRP approach. Simulated virtual screening experiments with MDL drug data report (MDDR) data sets showed that QPRP outperformed the classical ranking principle (PRP) for molecular chemical compounds.

  1. Quantum probability ranking principle for ligand-based virtual screening

    NASA Astrophysics Data System (ADS)

    Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal

    2017-04-01

    Chemical libraries contain thousands of compounds that need screening, which increases the need for computational methods that can rank or prioritize compounds. The tools of virtual screening are widely exploited to enhance the cost effectiveness of lead drug discovery programs by ranking chemical compounds databases in decreasing probability of biological activity based upon probability ranking principle (PRP). In this paper, we developed a novel ranking approach for molecular compounds inspired by quantum mechanics, called quantum probability ranking principle (QPRP). The QPRP ranking criteria would make an attempt to draw an analogy between the physical experiment and molecular structure ranking process for 2D fingerprints in ligand based virtual screening (LBVS). The development of QPRP criteria in LBVS has employed the concepts of quantum at three different levels, firstly at representation level, this model makes an effort to develop a new framework of molecular representation by connecting the molecular compounds with mathematical quantum space. Secondly, estimate the similarity between chemical libraries and references based on quantum-based similarity searching method. Finally, rank the molecules using QPRP approach. Simulated virtual screening experiments with MDL drug data report (MDDR) data sets showed that QPRP outperformed the classical ranking principle (PRP) for molecular chemical compounds.

  2. Final Report: A Broad Research Project on the Sciences of Complexity, September 15, 1994 - November 15, 1999

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2000-02-01

    DOE support for a broad research program in the sciences of complexity permitted the Santa Fe Institute to initiate new collaborative research within its integrative core activities as well as to host visitors to participate in research on specific topics that serve as motivation and testing ground for the study of the general principles of complex systems. Results are presented on computational biology, biodiversity and ecosystem research, and advanced computing and simulation.

  3. Synthetic biology platform technologies for antimicrobial applications.

    PubMed

    Braff, Dana; Shis, David; Collins, James J

    2016-10-01

    The growing prevalence of antibiotic resistance calls for new approaches in the development of antimicrobial therapeutics. Likewise, improved diagnostic measures are essential in guiding the application of targeted therapies and preventing the evolution of therapeutic resistance. Discovery platforms are also needed to form new treatment strategies and identify novel antimicrobial agents. By applying engineering principles to molecular biology, synthetic biologists have developed platforms that improve upon, supplement, and will perhaps supplant traditional broad-spectrum antibiotics. Efforts in engineering bacteriophages and synthetic probiotics demonstrate targeted antimicrobial approaches that can be fine-tuned using synthetic biology-derived principles. Further, the development of paper-based, cell-free expression systems holds promise in promoting the clinical translation of molecular biology tools for diagnostic purposes. In this review, we highlight emerging synthetic biology platform technologies that are geared toward the generation of new antimicrobial therapies, diagnostics, and discovery channels. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. How evolutionary principles improve the understanding of human health and disease.

    PubMed

    Gluckman, Peter D; Low, Felicia M; Buklijas, Tatjana; Hanson, Mark A; Beedle, Alan S

    2011-03-01

    An appreciation of the fundamental principles of evolutionary biology provides new insights into major diseases and enables an integrated understanding of human biology and medicine. However, there is a lack of awareness of their importance amongst physicians, medical researchers, and educators, all of whom tend to focus on the mechanistic (proximate) basis for disease, excluding consideration of evolutionary (ultimate) reasons. The key principles of evolutionary medicine are that selection acts on fitness, not health or longevity; that our evolutionary history does not cause disease, but rather impacts on our risk of disease in particular environments; and that we are now living in novel environments compared to those in which we evolved. We consider these evolutionary principles in conjunction with population genetics and describe several pathways by which evolutionary processes can affect disease risk. These perspectives provide a more cohesive framework for gaining insights into the determinants of health and disease. Coupled with complementary insights offered by advances in genomic, epigenetic, and developmental biology research, evolutionary perspectives offer an important addition to understanding disease. Further, there are a number of aspects of evolutionary medicine that can add considerably to studies in other domains of contemporary evolutionary studies.

  5. How evolutionary principles improve the understanding of human health and disease

    PubMed Central

    Gluckman, Peter D; Low, Felicia M; Buklijas, Tatjana; Hanson, Mark A; Beedle, Alan S

    2011-01-01

    An appreciation of the fundamental principles of evolutionary biology provides new insights into major diseases and enables an integrated understanding of human biology and medicine. However, there is a lack of awareness of their importance amongst physicians, medical researchers, and educators, all of whom tend to focus on the mechanistic (proximate) basis for disease, excluding consideration of evolutionary (ultimate) reasons. The key principles of evolutionary medicine are that selection acts on fitness, not health or longevity; that our evolutionary history does not cause disease, but rather impacts on our risk of disease in particular environments; and that we are now living in novel environments compared to those in which we evolved. We consider these evolutionary principles in conjunction with population genetics and describe several pathways by which evolutionary processes can affect disease risk. These perspectives provide a more cohesive framework for gaining insights into the determinants of health and disease. Coupled with complementary insights offered by advances in genomic, epigenetic, and developmental biology research, evolutionary perspectives offer an important addition to understanding disease. Further, there are a number of aspects of evolutionary medicine that can add considerably to studies in other domains of contemporary evolutionary studies. PMID:25567971

  6. A Free Energy Principle for Biological Systems

    PubMed Central

    Karl, Friston

    2012-01-01

    This paper describes a free energy principle that tries to explain the ability of biological systems to resist a natural tendency to disorder. It appeals to circular causality of the sort found in synergetic formulations of self-organization (e.g., the slaving principle) and models of coupled dynamical systems, using nonlinear Fokker Planck equations. Here, circular causality is induced by separating the states of a random dynamical system into external and internal states, where external states are subject to random fluctuations and internal states are not. This reduces the problem to finding some (deterministic) dynamics of the internal states that ensure the system visits a limited number of external states; in other words, the measure of its (random) attracting set, or the Shannon entropy of the external states is small. We motivate a solution using a principle of least action based on variational free energy (from statistical physics) and establish the conditions under which it is formally equivalent to the information bottleneck method. This approach has proved useful in understanding the functional architecture of the brain. The generality of variational free energy minimisation and corresponding information theoretic formulations may speak to interesting applications beyond the neurosciences; e.g., in molecular or evolutionary biology. PMID:23204829

  7. Integrating pharmacology topics in high school biology and chemistry classes improves performance

    NASA Astrophysics Data System (ADS)

    Schwartz-Bloom, Rochelle D.; Halpin, Myra J.

    2003-11-01

    Although numerous programs have been developed for Grade Kindergarten through 12 science education, evaluation has been difficult owing to the inherent problems conducting controlled experiments in the typical classroom. Using a rigorous experimental design, we developed and tested a novel program containing a series of pharmacology modules (e.g., drug abuse) to help high school students learn basic principles in biology and chemistry. High school biology and chemistry teachers were recruited for the study and they attended a 1-week workshop to learn how to integrate pharmacology into their teaching. Working with university pharmacology faculty, they also developed classroom activities. The following year, teachers field-tested the pharmacology modules in their classrooms. Students in classrooms using the pharmacology topics scored significantly higher on a multiple choice test of basic biology and chemistry concepts compared with controls. Very large effect sizes (up to 1.27 standard deviations) were obtained when teachers used as many as four modules. In addition, biology students increased performance on chemistry questions and chemistry students increased performance on biology questions. Substantial gains in achievement may be made when high school students are taught science using topics that are interesting and relevant to their own lives.

  8. Immunology and Homeopathy. 2. Cells of the Immune System and Inflammation

    PubMed Central

    Bellavite, Paolo; Conforti, Anita; Pontarollo, Francesco; Ortolani, Riccardo

    2006-01-01

    Here we describe the results of some experimental laboratory studies aimed at verifying the efficacy of high dilutions of substances and of homeopathic medicines in models of inflammation and immunity. Studies carried out on basophils, lymphocytes, granulocytes and fibroblasts are reviewed. This approach may help to test under controlled conditions the main principles of homeopathy such as ‘similarity’ of drug action at the cellular level and the effects of dilution/dynamization on the drug activity. The current situation is that few and rather small groups are working on laboratory models for homeopathy. Regarding the interpretation of data in view of the simile principle, we observe that there are different levels of similarity and that the laboratory data give support to this principle, but have not yet yielded the ultimate answer to the action mechanism of homeopathy. Evidence of the biological activity in vitro of highly diluted-dynamized solutions is slowly accumulating, with some conflicting reports. It is our hope that this review of literature unknown to most people will give an original and useful insight into the ‘state-of-the-art’ of homeopathy, without final conclusions ‘for’ or ‘against’ this modality. This kind of uncertainty may be difficult to accept, but is conceivably the most open-minded position now. PMID:16550219

  9. Metabolic principles of river basin organization.

    PubMed

    Rodriguez-Iturbe, Ignacio; Caylor, Kelly K; Rinaldo, Andrea

    2011-07-19

    The metabolism of a river basin is defined as the set of processes through which the basin maintains its structure and responds to its environment. Green (or biotic) metabolism is measured via transpiration and blue (or abiotic) metabolism through runoff. A principle of equal metabolic rate per unit area throughout the basin structure is developed and tested in a river basin characterized by large heterogeneities in precipitation, vegetation, soil, and geomorphology. This principle is suggested to have profound implications for the spatial organization of river basin hydrologic dynamics, including the minimization of energy expenditure known to control the scale-invariant characteristics of river networks over several orders of magnitude. Empirically derived, remarkably constant rates of average transpiration per unit area through the basin structure lead to a power law for the probability distribution of transpiration from a randomly chosen subbasin. The average runoff per unit area, evaluated for subbasins of a wide range of topological magnitudes, is also shown to be remarkably constant independently of size. A similar result is found for the rainfall after accounting for canopy interception. Allometric scaling of metabolic rates with size, variously addressed in the biological literature and network theory under the label of Kleiber's law, is similarly derived. The empirical evidence suggests that river basin metabolic activity is linked with the spatial organization that takes place around the drainage network and therefore with the mechanisms responsible for the fractal geometry of the network, suggesting a new coevolutionary framework for biological, geomorphological, and hydrologic dynamics.

  10. Similarity principles for the biology of pelagic animals

    PubMed Central

    Barenblatt, G. I.; Monin, A. S.

    1983-01-01

    A similarity principle is formulated according to which the statistical pattern of the pelagic population is identical in all scales sufficiently large in comparison with the molecular one. From this principle, a power law is obtained analytically for the pelagic animal biomass distribution over the animal sizes. A hypothesis is presented according to which, under fixed external conditions, the oxygen exchange intensity of an animal is governed only by its mass and density and by the specific absorbing capacity of the animal's respiratory organ. From this hypothesis a power law is obtained by the method of dimensional analysis for the exchange intensity mass dependence. The known empirical values of the exponent of this power law are interpreted as an indication that the oxygen-absorbing organs of the animals can be represented as so-called fractal surfaces. In conclusion the biological principle of the decrease in specific exchange intensity with increase in animal mass is discussed. PMID:16593327

  11. Supplementing Introductory Biology with On-Line Curriculum

    ERIC Educational Resources Information Center

    McGroarty, Estelle; Parker, Joyce; Heidemann, Merle; Lim, Heejun; Olson, Mark; Long, Tammy; Merrill, John; Riffell, Samuel; Smith, James; Batzli, Janet; Kirschtel, David

    2004-01-01

    We developed web-based modules addressing fundamental concepts of introductory biology delivered through the LON-CAPA course management system. These modules were designed and used to supplement large, lecture-based introductory biology classes. Incorporating educational principles and the strength of web-based instructional technology, choices…

  12. Endobiogeny: a global approach to systems biology (part 1 of 2).

    PubMed

    Lapraz, Jean-Claude; Hedayat, Kamyar M

    2013-01-01

    Endobiogeny is a global systems approach to human biology that may offer an advancement in clinical medicine based in scientific principles of rigor and experimentation and the humanistic principles of individualization of care and alleviation of suffering with minimization of harm. Endobiogeny is neither a movement away from modern science nor an uncritical embracing of pre-rational methods of inquiry but a synthesis of quantitative and qualitative relationships reflected in a systems-approach to life and based on new mathematical paradigms of pattern recognition.

  13. Deriving principles of microbiology by multiscaling laws of molecular physics.

    PubMed

    Ortoleva, Peter; Adhangale, P; Cheluvaraja, S; Fontus, Max; Shreif, Zeina

    2009-01-01

    It has long been an objective of the physical sciences to derive principles of biology from the laws of physics. At the angstrom scale for processes evolving on timescales of 10(-14) s, many systems can be characterized in terms of atomic vibrations and collisions. In contrast, biological systems display dramatic transformations including self-assembly and reorganization from one cell phenotype to another as the microenvironment changes. We have developed a framework for understanding the emergence of living systems from the underlying atomic chaos.

  14. High-Throughput Sequencing Reveals Principles of Adeno-Associated Virus Serotype 2 Integration

    PubMed Central

    Janovitz, Tyler; Klein, Isaac A.; Oliveira, Thiago; Mukherjee, Piali; Nussenzweig, Michel C.; Sadelain, Michel

    2013-01-01

    Viral integrations are important in human biology, yet genome-wide integration profiles have not been determined for many viruses. Adeno-associated virus (AAV) infects most of the human population and is a prevalent gene therapy vector. AAV integrates into the human genome with preference for a single locus, termed AAVS1. However, the genome-wide integration of AAV has not been defined, and the principles underlying this recombination remain unclear. Using a novel high-throughput approach, integrant capture sequencing, nearly 12 million AAV junctions were recovered from a human cell line, providing five orders of magnitude more data than were previously available. Forty-five percent of integrations occurred near AAVS1, and several thousand novel integration hotspots were identified computationally. Most of these occurred in genes, with dozens of hotspots targeting known oncogenes. Viral replication protein binding sites (RBS) and transcriptional activity were major factors favoring integration. In a first for eukaryotic viruses, the data reveal a unique asymmetric integration profile with distinctive directional orientation of viral genomes. These studies provide a new understanding of AAV integration biology through the use of unbiased high-throughput data acquisition and bioinformatics. PMID:23720718

  15. Total-Internal-Reflection Platforms for Chemical and Biological Sensing Applications

    NASA Astrophysics Data System (ADS)

    Sapsford, Kim E.

    Sensing platforms based on the principle of total internal reflection (TIR) represent a fairly mature yet still expanding and exciting field of research. Sensor development has mainly been driven by the need for rapid, stand-alone, automated devices for application in the fields of clinical diagnosis and screening, food and water safety, environmental monitoring, and chemical and biological warfare agent detection. The technologies highlighted in this chapter are continually evolving, taking advantage of emerging advances in microfabrication, lab-on-a-chip, excitation, and detection techniques. This chapter describes many of the underlying principles of TIR-based sensing platforms and additionally focusses on planar TIR fluorescence (TIRF)-based chemical and biological sensors.

  16. Biological Implications of Dynamical Phases in Non-equilibrium Networks

    NASA Astrophysics Data System (ADS)

    Murugan, Arvind; Vaikuntanathan, Suriyanarayanan

    2016-03-01

    Biology achieves novel functions like error correction, ultra-sensitivity and accurate concentration measurement at the expense of free energy through Maxwell Demon-like mechanisms. The design principles and free energy trade-offs have been studied for a variety of such mechanisms. In this review, we emphasize a perspective based on dynamical phases that can explain commonalities shared by these mechanisms. Dynamical phases are defined by typical trajectories executed by non-equilibrium systems in the space of internal states. We find that coexistence of dynamical phases can have dramatic consequences for function vs free energy cost trade-offs. Dynamical phases can also provide an intuitive picture of the design principles behind such biological Maxwell Demons.

  17. Designing a 'neotissue' using the principles of biology, chemistry and engineering.

    PubMed

    Nannaparaju, Madhusudhan; Oragui, Emeka; Khan, Wasim S

    2012-01-01

    The traditional methods of treating musculoskeletal injuries and disorders are not completely effective and have several limitations. Tissue engineering involves using the principles of biology, chemistry and engineering to design a 'neotissue' that augments a malfunctioning in vivo tissue. The main requirements for functional engineered tissue include reparative cellular components that proliferate on a scaffold grown within a bioreactor that provides specific biochemical and physical signals to regulate cell differentiation and tissue assembly. In this review we provide an overview of the biology of common musculoskeletal tissue and discuss their common pathologies. We also describe the commonly used stem cells, scaffolds and bioreactors and evaluate their role in issue engineering.

  18. Synergistic Synthetic Biology: Units in Concert

    PubMed Central

    Trosset, Jean-Yves; Carbonell, Pablo

    2013-01-01

    Synthetic biology aims at translating the methods and strategies from engineering into biology in order to streamline the design and construction of biological devices through standardized parts. Modular synthetic biology devices are designed by means of an adequate elimination of cross-talk that makes circuits orthogonal and specific. To that end, synthetic constructs need to be adequately optimized through in silico modeling by choosing the right complement of genetic parts and by experimental tuning through directed evolution and craftsmanship. In this review, we consider an additional and complementary tool available to the synthetic biologist for innovative design and successful construction of desired circuit functionalities: biological synergies. Synergy is a prevalent emergent property in biological systems that arises from the concerted action of multiple factors producing an amplification or cancelation effect compared with individual actions alone. Synergies appear in domains as diverse as those involved in chemical and protein activity, polypharmacology, and metabolic pathway complementarity. In conventional synthetic biology designs, synergistic cross-talk between parts and modules is generally attenuated in order to verify their orthogonality. Synergistic interactions, however, can induce emergent behavior that might prove useful for synthetic biology applications, like in functional circuit design, multi-drug treatment, or in sensing and delivery devices. Synergistic design principles are therefore complementary to those coming from orthogonal design and may provide added value to synthetic biology applications. The appropriate modeling, characterization, and design of synergies between biological parts and units will allow the discovery of yet unforeseeable, novel synthetic biology applications. PMID:25022769

  19. Synergistic Synthetic Biology: Units in Concert.

    PubMed

    Trosset, Jean-Yves; Carbonell, Pablo

    2013-01-01

    Synthetic biology aims at translating the methods and strategies from engineering into biology in order to streamline the design and construction of biological devices through standardized parts. Modular synthetic biology devices are designed by means of an adequate elimination of cross-talk that makes circuits orthogonal and specific. To that end, synthetic constructs need to be adequately optimized through in silico modeling by choosing the right complement of genetic parts and by experimental tuning through directed evolution and craftsmanship. In this review, we consider an additional and complementary tool available to the synthetic biologist for innovative design and successful construction of desired circuit functionalities: biological synergies. Synergy is a prevalent emergent property in biological systems that arises from the concerted action of multiple factors producing an amplification or cancelation effect compared with individual actions alone. Synergies appear in domains as diverse as those involved in chemical and protein activity, polypharmacology, and metabolic pathway complementarity. In conventional synthetic biology designs, synergistic cross-talk between parts and modules is generally attenuated in order to verify their orthogonality. Synergistic interactions, however, can induce emergent behavior that might prove useful for synthetic biology applications, like in functional circuit design, multi-drug treatment, or in sensing and delivery devices. Synergistic design principles are therefore complementary to those coming from orthogonal design and may provide added value to synthetic biology applications. The appropriate modeling, characterization, and design of synergies between biological parts and units will allow the discovery of yet unforeseeable, novel synthetic biology applications.

  20. Host Biology in Light of the Microbiome: Ten Principles of Holobionts and Hologenomes

    PubMed Central

    Bordenstein, Seth R.; Theis, Kevin R.

    2015-01-01

    Groundbreaking research on the universality and diversity of microorganisms is now challenging the life sciences to upgrade fundamental theories that once seemed untouchable. To fully appreciate the change that the field is now undergoing, one has to place the epochs and foundational principles of Darwin, Mendel, and the modern synthesis in light of the current advances that are enabling a new vision for the central importance of microbiology. Animals and plants are no longer heralded as autonomous entities but rather as biomolecular networks composed of the host plus its associated microbes, i.e., "holobionts." As such, their collective genomes forge a "hologenome," and models of animal and plant biology that do not account for these intergenomic associations are incomplete. Here, we integrate these concepts into historical and contemporary visions of biology and summarize a predictive and refutable framework for their evaluation. Specifically, we present ten principles that clarify and append what these concepts are and are not, explain how they both support and extend existing theory in the life sciences, and discuss their potential ramifications for the multifaceted approaches of zoology and botany. We anticipate that the conceptual and evidence-based foundation provided in this essay will serve as a roadmap for hypothesis-driven, experimentally validated research on holobionts and their hologenomes, thereby catalyzing the continued fusion of biology's subdisciplines. At a time when symbiotic microbes are recognized as fundamental to all aspects of animal and plant biology, the holobiont and hologenome concepts afford a holistic view of biological complexity that is consistent with the generally reductionist approaches of biology. PMID:26284777

  1. Firefly courtship as the basis of the synchronization-response principle

    NASA Astrophysics Data System (ADS)

    Ramírez Ávila, G. M.; Deneubourg, J.-L.; Guisset, J.-L.; Wessel, N.; Kurths, J.

    2011-06-01

    Response to synchronization seems to be a widespread phenomenon specially in biological systems. We highlight this phenomenon studying the courtship of flashing fireflies in which a typical collective rhythm occurring only among the males arises and it is followed by a response of the females. Based on a model issued from electronic fireflies, we explain the synchronization of the males and the active responses of the females in the courtship of mingled (both sexes) populations of fireflies. The model also explains the courtship behavior of other species whose interactions follow the same logic even if their physical features are different. Moreover, the model can make predictions on the behavior of mingled and mixed (natural and artificial) groups of such animals. This finding could be considered as the basis of a new principle, namely the synchronization-response.

  2. Adaptive force produced by stress-induced regulation of random variation intensity.

    PubMed

    Shimansky, Yury P

    2010-08-01

    The Darwinian theory of life evolution is capable of explaining the majority of related phenomena. At the same time, the mechanisms of optimizing traits beneficial to a population as a whole but not directly to an individual remain largely unclear. There are also significant problems with explaining the phenomenon of punctuated equilibrium. From another perspective, multiple mechanisms for the regulation of the rate of genetic mutations according to the environmental stress have been discovered, but their precise functional role is not well understood yet. Here a novel mathematical paradigm called a Kinetic-Force Principle (KFP), which can serve as a general basis for biologically plausible optimization methods, is introduced and its rigorous derivation is provided. Based on this principle, it is shown that, if the rate of random changes in a biological system is proportional, even only roughly, to the amount of environmental stress, a virtual force is created, acting in the direction of stress relief. It is demonstrated that KFP can provide important insights into solving the above problems. Evidence is presented in support of a hypothesis that the nature employs KFP for accelerating adaptation in biological systems. A detailed comparison between KFP and the principle of variation and natural selection is presented and their complementarity is revealed. It is concluded that KFP is not a competing alternative, but a powerful addition to the principle of variation and natural selection. It is also shown KFP can be used in multiple ways for adaptation of individual biological organisms.

  3. Shaping biological knowledge: applications in proteomics.

    PubMed

    Lisacek, F; Chichester, C; Gonnet, P; Jaillet, O; Kappus, S; Nikitin, F; Roland, P; Rossier, G; Truong, L; Appel, R

    2004-01-01

    The central dogma of molecular biology has provided a meaningful principle for data integration in the field of genomics. In this context, integration reflects the known transitions from a chromosome to a protein sequence: transcription, intron splicing, exon assembly and translation. There is no such clear principle for integrating proteomics data, since the laws governing protein folding and interactivity are not quite understood. In our effort to bring together independent pieces of information relative to proteins in a biologically meaningful way, we assess the bias of bioinformatics resources and consequent approximations in the framework of small-scale studies. We analyse proteomics data while following both a data-driven (focus on proteins smaller than 10 kDa) and a hypothesis-driven (focus on whole bacterial proteomes) approach. These applications are potentially the source of specialized complements to classical biological ontologies.

  4. Practopoiesis: or how life fosters a mind.

    PubMed

    Nikolić, Danko

    2015-05-21

    The mind is a biological phenomenon. Thus, biological principles of organization should also be the principles underlying mental operations. Practopoiesis states that the key for achieving intelligence through adaptation is an arrangement in which mechanisms laying at a lower level of organization, by their operations and interaction with the environment, enable creation of mechanisms laying at a higher level of organization. When such an organizational advance of a system occurs, it is called a traverse. A case of traverse is when plasticity mechanisms (at a lower level of organization), by their operations, create a neural network anatomy (at a higher level of organization). Another case is the actual production of behavior by that network, whereby the mechanisms of neuronal activity operate to create motor actions. Practopoietic theory explains why the adaptability of a system increases with each increase in the number of traverses. With a larger number of traverses, a system can be relatively small and yet, produce a higher degree of adaptive/intelligent behavior than a system with a lower number of traverses. The present analyses indicate that the two well-known traverses - neural plasticity and neural activity - are not sufficient to explain human mental capabilities. At least one additional traverse is needed, which is named anapoiesis for its contribution in reconstructing knowledge e.g., from long-term memory into working memory. The conclusions bear implications for brain theory, the mind-body explanatory gap, and developments of artificial intelligence technologies. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

  5. The art of curation at a biological database: principles and application

    USDA-ARS?s Scientific Manuscript database

    The variety and quantity of data being produced by biological research has grown dramatically in recent years, resulting in an expansion of our understanding of biological systems. However, this abundance of data has brought new challenges, especially in curation. The role of biocurators is in part ...

  6. Active control of complex, multicomponent self-assembly processes

    NASA Astrophysics Data System (ADS)

    Schulman, Rebecca

    The kinetics of many complex biological self-assembly processes such as cytoskeletal assembly are precisely controlled by cells. Spatiotemporal control over rates of filament nucleation, growth and disassembly determine how self-assembly occurs and how the assembled form changes over time. These reaction rates can be manipulated by changing the concentrations of the components needed for assembly by activating or deactivating them. I will describe how we can use these principles to design driven self-assembly processes in which we assemble and disassemble multiple types of components to create micron-scale networks of semiflexible filaments assembled from DNA. The same set of primitive components can be assembled into many different, structures depending on the concentrations of different components and how designed, DNA-based chemical reaction networks manipulate these concentrations over time. These chemical reaction networks can in turn interpret environmental stimuli to direct complex, multistage response. Such a system is a laboratory for understanding complex active material behaviors, such as metamorphosis, self-healing or adaptation to the environment that are ubiquitous in biological systems but difficult to quantitatively characterize or engineer.

  7. Savinin, a lignan from Pterocarpus santalinus inhibits tumor necrosis factor-alpha production and T cell proliferation.

    PubMed

    Cho, J Y; Park, J; Kim, P S; Yoo, E S; Baik, K U; Park, M H

    2001-02-01

    Two lignans were isolated from the heartwood of Pterocarpus santalinus by activity-guided fractionation and investigated for their biological properties and molecular mechanism of action. On the basis of their spectroscopic data, these compounds were identified as savinin (1) and calocedrin (2), dibenzyl butyrolactone-type lignan compounds having an alpha-arylidene gamma-lactone structure. These lignans significantly inhibited tumor necrosis factor (TNF)-a production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and T cell proliferation elicited by concanavalin (Con A), without displaying cytotoxicity. The molecular inhibitory mechanism of compound 1 was confirmed to be mediated by the non-polar butyrolactone ring, according to a structure-relationship study with structurally related and unrelated compounds, such as arctigenin (a dibenzyl butyrolactone type lignan), eudesmin (a furofuran type lignan), isolariciresinol (a dibenzylbutane type lignan), and cynaropicrin (a sesquiterpene lactone). The results suggest that savinin may act as an active principle in the reported biological activities of P. santalinus, such as antiinflammatory effect, by mediation of the butyrolactone ring as a valuable pharmacophore.

  8. Evolutionary principles and their practical application

    PubMed Central

    Hendry, Andrew P; Kinnison, Michael T; Heino, Mikko; Day, Troy; Smith, Thomas B; Fitt, Gary; Bergstrom, Carl T; Oakeshott, John; Jørgensen, Peter S; Zalucki, Myron P; Gilchrist, George; Southerton, Simon; Sih, Andrew; Strauss, Sharon; Denison, Robert F; Carroll, Scott P

    2011-01-01

    Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently in these different fields, even though the underlying fundamental concepts are the same. We explore these fundamental concepts under four main themes: variation, selection, connectivity, and eco-evolutionary dynamics. Within each theme, we present several key evolutionary principles and illustrate their use in addressing applied problems. We hope that the resulting primer of evolutionary concepts and their practical utility helps to advance a unified multidisciplinary field of applied evolutionary biology. PMID:25567966

  9. Evolutionary principles and their practical application.

    PubMed

    Hendry, Andrew P; Kinnison, Michael T; Heino, Mikko; Day, Troy; Smith, Thomas B; Fitt, Gary; Bergstrom, Carl T; Oakeshott, John; Jørgensen, Peter S; Zalucki, Myron P; Gilchrist, George; Southerton, Simon; Sih, Andrew; Strauss, Sharon; Denison, Robert F; Carroll, Scott P

    2011-03-01

    Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently in these different fields, even though the underlying fundamental concepts are the same. We explore these fundamental concepts under four main themes: variation, selection, connectivity, and eco-evolutionary dynamics. Within each theme, we present several key evolutionary principles and illustrate their use in addressing applied problems. We hope that the resulting primer of evolutionary concepts and their practical utility helps to advance a unified multidisciplinary field of applied evolutionary biology.

  10. Hierarchical functional organization of formal biological systems: a dynamical approach. II. The concept of non-symmetry leads to a criterion of evolution deduced from an optimum principle of the (O-FBS) sub-system.

    PubMed

    Chauvet, G A

    1993-03-29

    In paper I a theory of functional organization in terms of functional interactions was proposed for a formal biological system (FBS). A functional interaction was defined as the product emitted by a structural unit, i.e. an assembly of molecules, cells, tissues or organs, which acts on another. We have shown that a self-association hypothesis could be an explanation for the source of these functional interactions because it is consistent with increased stability of the system after association. The construction of the set of interactions provides the topology of the biological system, called (O-FBS), in contrast to the (D-FBS) which describes the dynamics of the processes associated with the functional interactions. In this paper, an optimum principle is established, due to the non-symmetry of functional interactions, which could explain the stability of an FBS, and a criterion of evolution for the hierarchical topological organization of a FBS during development is deduced from that principle. The combinatorics of the (O-FBS) leads to the topological stability of the related graph. It is shown that this problem can be expressed as the re-distribution of sources and sinks, when one of them is suppressed, given the constraint of the invariance of the physiological function. Such an optimum principle could be called a 'principle of increase in functional order by hierarchy'. The first step is the formulation of a 'potential' for the functional organization, which describes the ability of the system to combine functional interactions, such that the principle of vital coherence (paper I) is satisfied. This function measures the number of potential functional interactions. The second step is to discover the maximum of this function. Biological systems in such a state of maximum organization are shown to satisfy particular dynamics, which can be experimentally verified: either the number of sinks decreases, or this number increases, in a monotonic way. The class of systems considered here is assumed to satisfy such an extremum hypothesis. The third step is a study of the variation of the degree of organization (paper I), i.e. the number of structural units when the biological system is growing. We establish an optimum principle for a new function called 'orgatropy'. By adding a criterion of specialization to the system we show the emergence of a level of organization with a re-organization of the system.(ABSTRACT TRUNCATED AT 400 WORDS)

  11. What is Proof of Concept Research and how does it Generate Epistemic and Ethical Categories for Future Scientific Practice?

    PubMed

    Kendig, Catherine Elizabeth

    2016-06-01

    "Proof of concept" is a phrase frequently used in descriptions of research sought in program announcements, in experimental studies, and in the marketing of new technologies. It is often coupled with either a short definition or none at all, its meaning assumed to be fully understood. This is problematic. As a phrase with potential implications for research and technology, its assumed meaning requires some analysis to avoid it becoming a descriptive category that refers to all things scientifically exciting. I provide a short analysis of proof of concept research and offer an example of it within synthetic biology. I suggest that not only are there activities that circumscribe new epistemological categories but there are also associated normative ethical categories or principles linked to the research. I examine these and provide an outline for an alternative ethical account to describe these activities that I refer to as "extended agency ethics". This view is used to explain how the type of research described as proof of concept also provides an attendant proof of principle that is the result of decision-making that extends across practitioners, their tools, techniques, and the problem solving activities of other research groups.

  12. Advances in the management of rheumatoid arthritis.

    PubMed

    Dale, James

    2015-08-01

    Modern early rheumatoid arthritis strategies are usually based upon a number of important overarching principles: 1. early diagnosis facilitates early commencement of disease modifying anti-rheumatic therapy; 2. early commencement of treatment reduces the long-term risk of erosive damage and functional decline; 3. composite disease activity measures should be used to quantify global rheumatoid arthritis disease activity; and 4. therapy should be intensified until a predefined disease activity target has been achieved. A substantial minority of rheumatoid arthritis patients (approximately 40%) will experience an adequate response to methotrexate monotherapy; however, the remainder may require disease modifying anti-rheumatic combination therapy, and/or biologic therapy, to achieve disease activity targets. Importantly, short term trials of methotrexate monotherapy do not appear to disadvantage outcomes provided treatment continues to be intensified if disease activity targets are not achieved. © The Author(s) 2015.

  13. Using an FPLC to promote active learning of the principles of protein structure and purification.

    PubMed

    Robinson, Rebekah L; Neely, Amy E; Mojadedi, Wais; Threatt, Katie N; Davis, Nicole Y; Weiland, Mitch H

    2017-01-02

    The concepts of protein purification are often taught in undergraduate biology and biochemistry lectures and reinforced during laboratory exercises; however, very few reported activities allow students to directly gain experience using modern protein purification instruments, such as Fast Protein Liquid Chromatography (FPLC). This laboratory exercise uses size exclusion chromatography (SEC) and ion exchange (IEX) chromatography to separate a mixture of four different proteins. Students use an SEC chromatogram and corresponding SDS-PAGE gel to understand how protein conformations change under different conditions (i.e. native and non-native). Students explore strategies to separate co-eluting proteins by IEX chromatography. Using either cation or anion exchange, one protein is bound to the column while the other is collected in the flow-through. In this exercise, undergraduate students gain hands-on experience with experimental design, buffer and sample preparation, and implementation of instrumentation that is commonly used by experienced researchers while learning and applying the fundamental concepts of protein structure, protein purification, and SDS-PAGE. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(1):60-68, 2017. © 2016 The International Union of Biochemistry and Molecular Biology.

  14. Enhancing Reuse of Data and Biological Material in Medical Research: From FAIR to FAIR-Health

    PubMed Central

    Kohlmayer, Florian; Prasser, Fabian; Mayrhofer, Michaela Th.; Schlünder, Irene; Martin, Gillian M.; Casati, Sara; Koumakis, Lefteris; Wutte, Andrea; Kozera, Łukasz; Strapagiel, Dominik; Anton, Gabriele; Zanetti, Gianluigi; Sezerman, Osman Ugur; Mendy, Maimuna; Valík, Dalibor; Lavitrano, Marialuisa; Dagher, Georges; Zatloukal, Kurt; van Ommen, GertJan B.; Litton, Jan-Eric

    2018-01-01

    The known challenge of underutilization of data and biological material from biorepositories as potential resources for medical research has been the focus of discussion for over a decade. Recently developed guidelines for improved data availability and reusability—entitled FAIR Principles (Findability, Accessibility, Interoperability, and Reusability)—are likely to address only parts of the problem. In this article, we argue that biological material and data should be viewed as a unified resource. This approach would facilitate access to complete provenance information, which is a prerequisite for reproducibility and meaningful integration of the data. A unified view also allows for optimization of long-term storage strategies, as demonstrated in the case of biobanks. We propose an extension of the FAIR Principles to include the following additional components: (1) quality aspects related to research reproducibility and meaningful reuse of the data, (2) incentives to stimulate effective enrichment of data sets and biological material collections and its reuse on all levels, and (3) privacy-respecting approaches for working with the human material and data. These FAIR-Health principles should then be applied to both the biological material and data. We also propose the development of common guidelines for cloud architectures, due to the unprecedented growth of volume and breadth of medical data generation, as well as the associated need to process the data efficiently. PMID:29359962

  15. Enhancing Reuse of Data and Biological Material in Medical Research: From FAIR to FAIR-Health.

    PubMed

    Holub, Petr; Kohlmayer, Florian; Prasser, Fabian; Mayrhofer, Michaela Th; Schlünder, Irene; Martin, Gillian M; Casati, Sara; Koumakis, Lefteris; Wutte, Andrea; Kozera, Łukasz; Strapagiel, Dominik; Anton, Gabriele; Zanetti, Gianluigi; Sezerman, Osman Ugur; Mendy, Maimuna; Valík, Dalibor; Lavitrano, Marialuisa; Dagher, Georges; Zatloukal, Kurt; van Ommen, GertJan B; Litton, Jan-Eric

    2018-04-01

    The known challenge of underutilization of data and biological material from biorepositories as potential resources for medical research has been the focus of discussion for over a decade. Recently developed guidelines for improved data availability and reusability-entitled FAIR Principles (Findability, Accessibility, Interoperability, and Reusability)-are likely to address only parts of the problem. In this article, we argue that biological material and data should be viewed as a unified resource. This approach would facilitate access to complete provenance information, which is a prerequisite for reproducibility and meaningful integration of the data. A unified view also allows for optimization of long-term storage strategies, as demonstrated in the case of biobanks. We propose an extension of the FAIR Principles to include the following additional components: (1) quality aspects related to research reproducibility and meaningful reuse of the data, (2) incentives to stimulate effective enrichment of data sets and biological material collections and its reuse on all levels, and (3) privacy-respecting approaches for working with the human material and data. These FAIR-Health principles should then be applied to both the biological material and data. We also propose the development of common guidelines for cloud architectures, due to the unprecedented growth of volume and breadth of medical data generation, as well as the associated need to process the data efficiently.

  16. Biological life-support systems

    NASA Technical Reports Server (NTRS)

    Shepelev, Y. Y.

    1975-01-01

    The establishment of human living environments by biologic methods, utilizing the appropriate functions of autotrophic and heterotrophic organisms is examined. Natural biologic systems discussed in terms of modeling biologic life support systems (BLSS), the structure of biologic life support systems, and the development of individual functional links in biologic life support systems are among the factors considered. Experimental modeling of BLSS in order to determine functional characteristics, mechanisms by which stability is maintained, and principles underlying control and regulation is also discussed.

  17. Electron Bifurcation: Thermodynamics and Kinetics of Two-Electron Brokering in Biological Redox Chemistry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Peng; Yuly, Jonathon L.; Lubner, Carolyn E.

    How can proteins drive two electrons from a redox active donor onto two acceptors at very different potentials and distances? And how can this transaction be conducted without dissipating very much energy or violating the laws of thermodynamics? Nature appears to have addressed these challenges by coupling thermodynamically uphill and downhill electron transfer reactions, using two-electron donor cofactors that have very different potentials for the removal of the first and second electron. Although electron bifurcation is carried out with near perfection from the standpoint of energy conservation and electron delivery yields, it is a biological energy transduction paradigm that hasmore » only come into focus recently. This Account provides an exegesis of the biophysical principles that underpin electron bifurcation.« less

  18. Multiscale mechanobiology: computational models for integrating molecules to multicellular systems

    PubMed Central

    Mak, Michael; Kim, Taeyoon

    2015-01-01

    Mechanical signals exist throughout the biological landscape. Across all scales, these signals, in the form of force, stiffness, and deformations, are generated and processed, resulting in an active mechanobiological circuit that controls many fundamental aspects of life, from protein unfolding and cytoskeletal remodeling to collective cell motions. The multiple scales and complex feedback involved present a challenge for fully understanding the nature of this circuit, particularly in development and disease in which it has been implicated. Computational models that accurately predict and are based on experimental data enable a means to integrate basic principles and explore fine details of mechanosensing and mechanotransduction in and across all levels of biological systems. Here we review recent advances in these models along with supporting and emerging experimental findings. PMID:26019013

  19. Exciting middle and high school students about immunology: an easy, inquiry-based lesson.

    PubMed

    Lukin, Kara

    2013-03-01

    High school students in the United States are apathetic about science, technology, engineering and mathematics (STEM), and the workforce pipeline in these areas is collapsing. The lack of understanding of basic principles of biology means that students are unable to make educated decisions concerning their personal health. To address these issues, we have developed a simple, inquiry-based outreach lesson centered on a mouse dissection. Students learn key concepts in immunology and enhance their understanding of human organ systems. The experiment highlights aspects of the scientific method and authentic data collection and analysis. This hands-on activity stimulates interest in biology, personal health and careers in STEM fields. Here, we present all the information necessary to execute the lesson effectively with middle and high school students.

  20. Identification of Modules in Protein-Protein Interaction Networks

    NASA Astrophysics Data System (ADS)

    Erten, Sinan; Koyutürk, Mehmet

    In biological systems, most processes are carried out through orchestration of multiple interacting molecules. These interactions are often abstracted using network models. A key feature of cellular networks is their modularity, which contributes significantly to the robustness, as well as adaptability of biological systems. Therefore, modularization of cellular networks is likely to be useful in obtaining insights into the working principles of cellular systems, as well as building tractable models of cellular organization and dynamics. A common, high-throughput source of data on molecular interactions is in the form of physical interactions between proteins, which are organized into protein-protein interaction (PPI) networks. This chapter provides an overview on identification and analysis of functional modules in PPI networks, which has been an active area of research in the last decade.

  1. Introduction to tissue engineering and application for cartilage engineering.

    PubMed

    de Isla, N; Huseltein, C; Jessel, N; Pinzano, A; Decot, V; Magdalou, J; Bensoussan, D; Stoltz, J-F

    2010-01-01

    Tissue engineering is a multidisciplinary field that applies the principles of engineering, life sciences, cell and molecular biology toward the development of biological substitutes that restore, maintain, and improve tissue function. In Western Countries, tissues or cells management for clinical uses is a medical activity governed by different laws. Three general components are involved in tissue engineering: (1) reparative cells that can form a functional matrix; (2) an appropriate scaffold for transplantation and support; and (3) bioreactive molecules, such as cytokines and growth factors that will support and choreograph formation of the desired tissue. These three components may be used individually or in combination to regenerate organs or tissues. Thus the growing development of tissue engineering needs to solve four main problems: cells, engineering development, grafting and safety studies.

  2. Development of a modified Hess-Murray law for non-Newtonian fluids in bifurcating micro-channels

    NASA Astrophysics Data System (ADS)

    Emerson, David; Barber, Robert

    2012-11-01

    Microfluidic manifolds frequently require the use of bifurcating channels and these can be used to create precise concentration gradients for chemical applications. More recently, novel devices have been attempting to replicate vasculatures or bronchial structures occurring in nature with the goal of creating artificial bifurcations that mimic the basic principles of designs found in nature. In previous work, we have used the biological principles behind the Hess-Murray Law, where bifurcating structures exhibit a constant stress profile and follow a third-power rule, to enable rectangular or trapezoidal micro-channels to be fabricated using conventional lithographic or wet-etching techniques. Using biological principles to design man made devices is generally referred to as biomimetics and this approach has found success in a range of new and emerging topics. However, our previous work was limited to Newtonian flows. More recently, we have used the Rabinovitsch-Mooney equation to be able to extend our analysis to non-Newtonian fluids. This has allowed us to develop a new rule that can provide a design criterion to predict channel dimensions for non-Newtonian flows obeying a constant stress biological principle. The Engineering and Physical Sciences Research Council for support of CCP12 and Programme Grant award (grant number EP/I011927/1).

  3. In Situ Biodosimetric Experiment for Space Applications

    NASA Astrophysics Data System (ADS)

    Goldschmidt, Gergely; Kovaliczky, Éva; Szabó, József; Rontó, Györgyi; Bérces, Attila

    2012-06-01

    This paper presents the principles and application of DNA based biological UV dosimeters, as developed by Research Group for Biophysics (RGB). These dosimeters are used for assessing the biological hazard of living systems on the Earth's surface and in different waters (rivers, lakes, seas, etc.). The UV dosimetry system has also been used in the space. In dosimeters a bacterial virus, bacteriophage T7 and polycrystalline uracil thin layers have been used as biological detectors. On the Earth's surface the UV radiation induces dimer formation in phage T7 and in the uracil detector, which was evaluated by loss of viability of the phage particles and by the decrease of the characteristic optical density (OD) of uracil thin layers. Recently the development of human space activities has also increased the need to measure the biological effect of extraterrestrial solar radiation, too. The evaluation of the space samples occurred on ground, thus only the starting and the final state were taken into account. A new improved, automated method is presented below which makes data collection more efficient and also makes the dynamics of the process observable.

  4. A review on plants extract mediated synthesis of silver nanoparticles for antimicrobial applications: A green expertise

    PubMed Central

    Ahmed, Shakeel; Ahmad, Mudasir; Swami, Babu Lal; Ikram, Saiqa

    2015-01-01

    Metallic nanoparticles are being utilized in every phase of science along with engineering including medical fields and are still charming the scientists to explore new dimensions for their respective worth which is generally attributed to their corresponding small sizes. The up-and-coming researches have proven their antimicrobial significance. Among several noble metal nanoparticles, silver nanoparticles have attained a special focus. Conventionally silver nanoparticles are synthesized by chemical method using chemicals as reducing agents which later on become accountable for various biological risks due to their general toxicity; engendering the serious concern to develop environment friendly processes. Thus, to solve the objective; biological approaches are coming up to fill the void; for instance green syntheses using biological molecules derived from plant sources in the form of extracts exhibiting superiority over chemical and/or biological methods. These plant based biological molecules undergo highly controlled assembly for making them suitable for the metal nanoparticle syntheses. The present review explores the huge plant diversity to be utilized towards rapid and single step protocol preparatory method with green principles over the conventional ones and describes the antimicrobial activities of silver nanoparticles. PMID:26843966

  5. Design Principles of Regulatory Networks: Searching for the Molecular Algorithms of the Cell

    PubMed Central

    Lim, Wendell A.; Lee, Connie M.; Tang, Chao

    2013-01-01

    A challenge in biology is to understand how complex molecular networks in the cell execute sophisticated regulatory functions. Here we explore the idea that there are common and general principles that link network structures to biological functions, principles that constrain the design solutions that evolution can converge upon for accomplishing a given cellular task. We describe approaches for classifying networks based on abstract architectures and functions, rather than on the specific molecular components of the networks. For any common regulatory task, can we define the space of all possible molecular solutions? Such inverse approaches might ultimately allow the assembly of a design table of core molecular algorithms that could serve as a guide for building synthetic networks and modulating disease networks. PMID:23352241

  6. Nature of the Physical Observer

    NASA Astrophysics Data System (ADS)

    Osoroma, Drahcir S.

    2010-12-01

    The nature of the observer has long plagued physical science. Here we review the current status of cognitive science in the context of a cosmology of mind in an Anthropic Multiverse. The concept of an élan vital or life force has long been considered the elementary action principle driving the evolution of living-systems by theologically minded scientists and individuals. Sufficiently extending Einstein's original model of a Static Universe, to a Holographic Anthropic Multiverse (HAM), provides a context for solving this centuries old problem for introducing this type of teleological principle into Physics, Biology, Medicine and Psychology. This means the contemporary framework of biological mechanism should no longer be considered the formal philosophical basis for describing living systems and contemporary allopathic (scientific) medicine. The new noetic action principle has far reaching implications for medicine and transpersonal psychology.

  7. Synthetic Biology: Knowledge Accessed by Everyone (Open Sources)

    ERIC Educational Resources Information Center

    Sánchez Reyes, Patricia Margarita

    2016-01-01

    Using the principles of biology, along with engineering and with the help of computer, scientists manage to copy. DNA sequences from nature and use them to create new organisms. DNA is created through engineering and computer science managing to create life inside a laboratory. We cannot dismiss the role that synthetic biology could lead in…

  8. Incorporating Molecular and Cellular Biology into a Chemical Engineering Degree Program

    ERIC Educational Resources Information Center

    O'Connor, Kim C.

    2005-01-01

    There is a growing need for a workforce that can apply engineering principles to molecular based discovery and product development in the biological sciences. To this end, Tulane University established a degree program that incorporates molecular and cellular biology into the chemical engineering curriculum. In celebration of the tenth anniversary…

  9. New Trends in Biology Teaching. Volume II.

    ERIC Educational Resources Information Center

    Heller, R.

    The papers presented in this second volume were either written specially for it, or were published in leading biology teaching periodicals of the world in 1966 and 1967. The first section deals with the principles of biology teaching, its purpose, its implication in everyday life, and the social responsibilities of its teachers. The second section…

  10. Meeting Report: Synthetic Biology Jamboree for Undergraduates

    ERIC Educational Resources Information Center

    Campbell, A. Malcolm

    2005-01-01

    The field of synthetic biology (the name is derived from an analogy to synthetic chemistry) has recognized itself as a "field" only since about 2002. Synthetic biology has gotten some high-profile attention recently, but most people are not aware the field even exists. Synthetic biologists apply engineering principles to genomic circuits to…

  11. 75 FR 52533 - Public Meeting of the Presidential Commission for the Study of Bioethical Issues

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... biology, including its potential benefits and risks, and appropriate ethical boundaries and principles... synthetic biology, the challenges and risks, and the ethical boundaries that may be important to formulation...

  12. Foreword to 'Multiscale structural biology: biophysical principles and mechanisms underlying the action of bio-nanomachines', a special issue in Honour of Fumio Arisaka's 70th birthday.

    PubMed

    Hall, Damien; Takagi, Junichi; Nakamura, Haruki

    2018-04-01

    This issue of Biophysical Reviews, titled 'Multiscale structural biology: biophysical principles and mechanisms underlying the action of bio-nanomachines', is a collection of articles dedicated in honour of Professor Fumio Arisaka's 70th birthday. Initially, working in the fields of haemocyanin and actin filament assembly, Fumio went on to publish important work on the elucidation of structural and functional aspects of T4 phage biology. As his career has transitioned levels of complexity from proteins (hemocyanin) to large protein complexes (actin) to even more massive bio-nanomachinery (phage), it is fitting that the subject of this special issue is similarly reflective of his multiscale approach to structural biology. This festschrift contains articles spanning biophysical structure and function from the bio-molecular through to the bio-nanomachine level.

  13. Topological properties of robust biological and computational networks

    PubMed Central

    Navlakha, Saket; He, Xin; Faloutsos, Christos; Bar-Joseph, Ziv

    2014-01-01

    Network robustness is an important principle in biology and engineering. Previous studies of global networks have identified both redundancy and sparseness as topological properties used by robust networks. By focusing on molecular subnetworks, or modules, we show that module topology is tightly linked to the level of environmental variability (noise) the module expects to encounter. Modules internal to the cell that are less exposed to environmental noise are more connected and less robust than external modules. A similar design principle is used by several other biological networks. We propose a simple change to the evolutionary gene duplication model which gives rise to the rich range of module topologies observed within real networks. We apply these observations to evaluate and design communication networks that are specifically optimized for noisy or malicious environments. Combined, joint analysis of biological and computational networks leads to novel algorithms and insights benefiting both fields. PMID:24789562

  14. Database on pharmacophore analysis of active principles, from medicinal plants

    PubMed Central

    Pitchai, Daisy; Manikkam, Rajalakshmi; Rajendran, Sasikala R; Pitchai, Gnanamani

    2010-01-01

    Plants continue to be a major source of medicines, as they have been throughout human history. In the present days, drug discovery from plants involves a multidisciplinary approach combining ethnobotanical, phytochemical and biological techniques to provide us new chemical compounds (lead molecules) for the development of drugs against various pharmacological targets, including cancer, diabetes and its secondary complications. In view of this need in current drug discovery from medicinal plants, here we describe another web database containing the information of pharmacophore analysis of active principles possessing antidiabetic, antimicrobial, anticancerous and antioxidant properties from medicinal plants. The database provides the botanical, taxonomic classification, biochemical as well as pharmacological properties of medicinal plants. Data on antidiabetic, antimicrobial, anti oxidative, anti tumor and anti inflammatory compounds, and their physicochemical properties, SMILES Notation, Lipinski's properties are included in our database. One of the proposed features in the database is the predicted ADMET values and the interaction of bioactive compounds to the target protein. The database alphabetically lists the compound name and also provides tabs separating for anti microbial, antitumor, antidiabetic, and antioxidative compounds. Availability http://www.hccbif.info / PMID:21346859

  15. A Comprehensive Experiment for Molecular Biology: Determination of Single Nucleotide Polymorphism in Human REV3 Gene Using PCR-RFLP

    ERIC Educational Resources Information Center

    Zhang, Xu; Shao, Meng; Gao, Lu; Zhao, Yuanyuan; Sun, Zixuan; Zhou, Liping; Yan, Yongmin; Shao, Qixiang; Xu, Wenrong; Qian, Hui

    2017-01-01

    Laboratory exercise is helpful for medical students to understand the basic principles of molecular biology and to learn about the practical applications of molecular biology. We have designed a lab course on molecular biology about the determination of single nucleotide polymorphism (SNP) in human REV3 gene, the product of which is a subunit of…

  16. Modeling mammary organogenesis from biological first principles: Cells and their physical constraints.

    PubMed

    Montévil, Maël; Speroni, Lucia; Sonnenschein, Carlos; Soto, Ana M

    2016-10-01

    In multicellular organisms, relations among parts and between parts and the whole are contextual and interdependent. These organisms and their cells are ontogenetically linked: an organism starts as a cell that divides producing non-identical cells, which organize in tri-dimensional patterns. These association patterns and cells types change as tissues and organs are formed. This contextuality and circularity makes it difficult to establish detailed cause and effect relationships. Here we propose an approach to overcome these intrinsic difficulties by combining the use of two models; 1) an experimental one that employs 3D culture technology to obtain the structures of the mammary gland, namely, ducts and acini, and 2) a mathematical model based on biological principles. The typical approach for mathematical modeling in biology is to apply mathematical tools and concepts developed originally in physics or computer sciences. Instead, we propose to construct a mathematical model based on proper biological principles. Specifically, we use principles identified as fundamental for the elaboration of a theory of organisms, namely i) the default state of cell proliferation with variation and motility and ii) the principle of organization by closure of constraints. This model has a biological component, the cells, and a physical component, a matrix which contains collagen fibers. Cells display agency and move and proliferate unless constrained; they exert mechanical forces that i) act on collagen fibers and ii) on other cells. As fibers organize, they constrain the cells on their ability to move and to proliferate. The model exhibits a circularity that can be interpreted in terms of closure of constraints. Implementing the mathematical model shows that constraints to the default state are sufficient to explain ductal and acinar formation, and points to a target of future research, namely, to inhibitors of cell proliferation and motility generated by the epithelial cells. The success of this model suggests a step-wise approach whereby additional constraints imposed by the tissue and the organism could be examined in silico and rigorously tested by in vitro and in vivo experiments, in accordance with the organicist perspective we embrace. Copyright © 2016. Published by Elsevier Ltd.

  17. Modeling mammary organogenesis from biological first principles: Cells and their physical constraints

    PubMed Central

    Montévil, Maël; Speroni, Lucia; Sonnenschein, Carlos; Soto, Ana M.

    2017-01-01

    In multicellular organisms, relations among parts and between parts and the whole are contextual and interdependent. These organisms and their cells are ontogenetically linked: an organism starts as a cell that divides producing non-identical cells, which organize in tri-dimensional patterns. These association patterns and cells types change as tissues and organs are formed. This contextuality and circularity makes it difficult to establish detailed cause and effect relationships. Here we propose an approach to overcome these intrinsic difficulties by combining the use of two models; 1) an experimental one that employs 3D culture technology to obtain the structures of the mammary gland, namely, ducts and acini, and 2) a mathematical model based on biological principles. The typical approach for mathematical modeling in biology is to apply mathematical tools and concepts developed originally in physics or computer sciences. Instead, we propose to construct a mathematical model based on proper biological principles. Specifically, we use principles identified as fundamental for the elaboration of a theory of organisms, namely i) the default state of cell proliferation with variation and motility and ii) the principle of organization by closure of constraints. This model has a biological component, the cells, and a physical component, a matrix which contains collagen fibers. Cells display agency and move and proliferate unless constrained; they exert mechanical forces that i) act on collagen fibers and ii) on other cells. As fibers organize, they constrain the cells on their ability to move and to proliferate. The model exhibits a circularity that can be interpreted in terms of closure of constraints. Implementing the mathematical model shows that constraints to the default state are sufficient to explain ductal and acinar formation, and points to a target of future research, namely, to inhibitors of cell proliferation and motility generated by the epithelial cells. The success of this model suggests a step-wise approach whereby additional constraints imposed by the tissue and the organism could be examined in silico and rigorously tested by in vitro and in vivo experiments, in accordance with the organicist perspective we embrace. PMID:27544910

  18. Physical principles of intracellular organization via active and passive phase transitions

    NASA Astrophysics Data System (ADS)

    Berry, Joel; Brangwynne, Clifford P.; Haataja, Mikko

    2018-04-01

    Exciting recent developments suggest that phase transitions represent an important and ubiquitous mechanism underlying intracellular organization. We describe key experimental findings in this area of study, as well as the application of classical theoretical approaches for quantitatively understanding these data. We also discuss the way in which equilibrium thermodynamic driving forces may interface with the fundamentally out-of-equilibrium nature of living cells. In particular, time and/or space-dependent concentration profiles may modulate the phase behavior of biomolecules in living cells. We suggest future directions for both theoretical and experimental work that will shed light on the way in which biological activity modulates the assembly, properties, and function of viscoelastic states of living matter.

  19. Physical principles of intracellular organization via active and passive phase transitions.

    PubMed

    Berry, Joel; Brangwynne, Clifford P; Haataja, Mikko

    2018-04-01

    Exciting recent developments suggest that phase transitions represent an important and ubiquitous mechanism underlying intracellular organization. We describe key experimental findings in this area of study, as well as the application of classical theoretical approaches for quantitatively understanding these data. We also discuss the way in which equilibrium thermodynamic driving forces may interface with the fundamentally out-of-equilibrium nature of living cells. In particular, time and/or space-dependent concentration profiles may modulate the phase behavior of biomolecules in living cells. We suggest future directions for both theoretical and experimental work that will shed light on the way in which biological activity modulates the assembly, properties, and function of viscoelastic states of living matter.

  20. Principles and Practices Fostering Inclusive Excellence: Lessons from the Howard Hughes Medical Institute's Capstone Institutions.

    PubMed

    DiBartolo, Patricia Marten; Gregg-Jolly, Leslie; Gross, Deborah; Manduca, Cathryn A; Iverson, Ellen; Cooke, David B; Davis, Gregory K; Davidson, Cameron; Hertz, Paul E; Hibbard, Lisa; Ireland, Shubha K; Mader, Catherine; Pai, Aditi; Raps, Shirley; Siwicki, Kathleen; Swartz, Jim E

    Best-practices pedagogy in science, technology, engineering, and mathematics (STEM) aims for inclusive excellence that fosters student persistence. This paper describes principles of inclusivity across 11 primarily undergraduate institutions designated as Capstone Awardees in Howard Hughes Medical Institute's (HHMI) 2012 competition. The Capstones represent a range of institutional missions, student profiles, and geographical locations. Each successfully directed activities toward persistence of STEM students, especially those from traditionally underrepresented groups, through a set of common elements: mentoring programs to build community; research experiences to strengthen scientific skill/identity; attention to quantitative skills; and outreach/bridge programs to broaden the student pool. This paper grounds these program elements in learning theory, emphasizing their essential principles with examples of how they were implemented within institutional contexts. We also describe common assessment approaches that in many cases informed programming and created traction for stakeholder buy-in. The lessons learned from our shared experiences in pursuit of inclusive excellence, including the resources housed on our companion website, can inform others' efforts to increase access to and persistence in STEM in higher education. © 2016 P. M. DiBartolo, L. Gregg-Jolly, D. Gross, C. A. Manduca, E. Iverson, et al. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  1. The principle of sufficiency and the evolution of control: using control analysis to understand the design principles of biological systems.

    PubMed

    Brown, Guy C

    2010-10-01

    Control analysis can be used to try to understand why (quantitatively) systems are the way that they are, from rate constants within proteins to the relative amount of different tissues in organisms. Many biological parameters appear to be optimized to maximize rates under the constraint of minimizing space utilization. For any biological process with multiple steps that compete for control in series, evolution by natural selection will tend to even out the control exerted by each step. This is for two reasons: (i) shared control maximizes the flux for minimum protein concentration, and (ii) the selection pressure on any step is proportional to its control, and selection will, by increasing the rate of a step (relative to other steps), decrease its control over a pathway. The control coefficient of a parameter P over fitness can be defined as (∂N/N)/(∂P/P), where N is the number of individuals in the population, and ∂N is the change in that number as a result of the change in P. This control coefficient is equal to the selection pressure on P. I argue that biological systems optimized by natural selection will conform to a principle of sufficiency, such that the control coefficient of all parameters over fitness is 0. Thus in an optimized system small changes in parameters will have a negligible effect on fitness. This principle naturally leads to (and is supported by) the dominance of wild-type alleles over null mutants.

  2. Search for organising principles: understanding in systems biology.

    PubMed

    Mesarovic, M D; Sreenath, S N; Keene, J D

    2004-06-01

    Due in large measure to the explosive progress in molecular biology, biology has become arguably the most exciting scientific field. The first half of the 21st century is sometimes referred to as the 'era of biology', analogous to the first half of the 20th century, which was considered to be the 'era of physics'. Yet, biology is facing a crisis--or is it an opportunity--reminiscent of the state of biology in pre-double-helix time. The principal challenge facing systems biology is complexity. According to Hood, 'Systems biology defines and analyses the interrelationships of all of the elements in a functioning system in order to understand how the system works.' With 30000+ genes in the human genome the study of all relationships simultaneously becomes a formidably complex problem. Hanahan and Weinberg raised the question as to whether progress will consist of 'adding further layers of complexity to a scientific literature that is already complex almost beyond measure' or whether the progress will lead to a 'science with a conceptual structure and logical coherence that rivals that of chemistry or physics.' At the core of the challenge is the need for a new approach, a shift from reductionism to a holistic perspective. However, more than just a pronouncement of a new approach is needed. We suggest that what is needed is to provide a conceptual framework for systems biology research. We propose that the concept of a complex system, i.e. a system of systems as defined in mathematical general systems theory (MGST), is central to provide such a framework. We further argue that for a deeper understanding in systems biology investigations should go beyond building numerical mathematical or computer models--important as they are. Biological phenomena cannot be predicted with the level of numerical precision as in classical physics. Explanations in terms of how the categories of systems are organised to function in ever changing conditions are more revealing. Non-numerical mathematical tools are appropriate for the task. Such a categorical perspective led us to propose that the core of understanding in systems biology depends on the search for organising principles rather than solely on construction of predictive descriptions (i.e. models) that exactly outline the evolution of systems in space and time. The search for organising principles requires an identification/discovery of new concepts and hypotheses. Some of them, such as coordination motifs for transcriptional regulatory networks and bounded autonomy of levccels in a hierarchy, are outlined in this article. Experimental designs are outlined to help verify the applicability of the interaction balance principle of coordination to transcriptional and posttranscriptional networks.

  3. Genomic signal processing: from matrix algebra to genetic networks.

    PubMed

    Alter, Orly

    2007-01-01

    DNA microarrays make it possible, for the first time, to record the complete genomic signals that guide the progression of cellular processes. Future discovery in biology and medicine will come from the mathematical modeling of these data, which hold the key to fundamental understanding of life on the molecular level, as well as answers to questions regarding diagnosis, treatment, and drug development. This chapter reviews the first data-driven models that were created from these genome-scale data, through adaptations and generalizations of mathematical frameworks from matrix algebra that have proven successful in describing the physical world, in such diverse areas as mechanics and perception: the singular value decomposition model, the generalized singular value decomposition model comparative model, and the pseudoinverse projection integrative model. These models provide mathematical descriptions of the genetic networks that generate and sense the measured data, where the mathematical variables and operations represent biological reality. The variables, patterns uncovered in the data, correlate with activities of cellular elements such as regulators or transcription factors that drive the measured signals and cellular states where these elements are active. The operations, such as data reconstruction, rotation, and classification in subspaces of selected patterns, simulate experimental observation of only the cellular programs that these patterns represent. These models are illustrated in the analyses of RNA expression data from yeast and human during their cell cycle programs and DNA-binding data from yeast cell cycle transcription factors and replication initiation proteins. Two alternative pictures of RNA expression oscillations during the cell cycle that emerge from these analyses, which parallel well-known designs of physical oscillators, convey the capacity of the models to elucidate the design principles of cellular systems, as well as guide the design of synthetic ones. In these analyses, the power of the models to predict previously unknown biological principles is demonstrated with a prediction of a novel mechanism of regulation that correlates DNA replication initiation with cell cycle-regulated RNA transcription in yeast. These models may become the foundation of a future in which biological systems are modeled as physical systems are today.

  4. Approaching the thermodynamic view of protein folding through the reproduction of Anfinsen's experiment by undergraduate physical biochemistry students.

    PubMed

    Fernandez-Reche, Andres; Cobos, Eva S; Luque, Irene; Ruiz-Sanz, Javier; Martinez, Jose C

    2018-01-04

    In 1972 Christian B. Anfinsen received the Nobel Prize in Chemistry for "…his work on ribonuclease, especially concerning the connection between the amino acid sequence and the biologically active conformation." The understanding of this principle is crucial for physical biochemistry students, since protein folding studies, bio-computing sciences and protein design approaches are founded on such a well-demonstrated connection. Herein, we describe a detailed and easy-to-follow experiment to reproduce the most relevant assays carried out at Anfinsen's laboratory in the 60s. This experiment provides students with a platform to interpret by themselves the structural and kinetic experiments conceived to understand the protein folding problem. In addition, this three-day experiment brings students a nice opportunity for protein manipulation as well as for the setting up of spectroscopic and chromatographic techniques. © 2018 by The International Union of Biochemistry and Molecular Biology, 2018. © 2018 The International Union of Biochemistry and Molecular Biology.

  5. [Problems of world outlook and methodology of science integration in biological studies].

    PubMed

    Khododova, Iu D

    1981-01-01

    Problems of worldoutlook and methodology of the natural-science knowledge are considered basing on the analysis of tendencies in the development of the membrane theory of cell processes and the use of principles of biological membrane functioning when solving some scientific and applied problems pertaining to different branches of chemistry and biology. The notion scientific knowledge integration is defined as interpenetration of approaches, methods and ideas of different branches of knowledge and enrichment on this basis of their content resulting in knowledge augmentation in each field taken separately. These processes are accompanied by appearance of new branches of knowledge - sciences "on junction" and their subsequent differentiations. The analysis of some gnoseological situations shows that integration of sciences contributes to coordination and some agreement of thinking styles of different specialists, puts forward keen personality of a scientist demanding, in particular, his high professional mobility. Problems of scientific activity organization are considered, which involve social sciences into the integration processes. The role of philosophy in the integration processes is emphasized.

  6. Bioinspired microrobots

    NASA Astrophysics Data System (ADS)

    Palagi, Stefano; Fischer, Peer

    2018-06-01

    Microorganisms can move in complex media, respond to the environment and self-organize. The field of microrobotics strives to achieve these functions in mobile robotic systems of sub-millimetre size. However, miniaturization of traditional robots and their control systems to the microscale is not a viable approach. A promising alternative strategy in developing microrobots is to implement sensing, actuation and control directly in the materials, thereby mimicking biological matter. In this Review, we discuss design principles and materials for the implementation of robotic functionalities in microrobots. We examine different biological locomotion strategies, and we discuss how they can be artificially recreated in magnetic microrobots and how soft materials improve control and performance. We show that smart, stimuli-responsive materials can act as on-board sensors and actuators and that `active matter' enables autonomous motion, navigation and collective behaviours. Finally, we provide a critical outlook for the field of microrobotics and highlight the challenges that need to be overcome to realize sophisticated microrobots, which one day might rival biological machines.

  7. A real-time measurement system for parameters of live biology metabolism process with fiber optics

    NASA Astrophysics Data System (ADS)

    Tao, Wei; Zhao, Hui; Liu, Zemin; Cheng, Jinke; Cai, Rong

    2010-08-01

    Energy metabolism is one of the basic life activities of cellular in which lactate, O2 and CO2 will be released into the extracellular environment. By monitoring the quantity of these parameters, the mitochondrial performance will be got. A continuous measurement system for the concentration of O2, CO2 and PH value is introduced in this paper. The system is made up of several small-sized fiber optics biosensors corresponding to the container. The setup of the system and the principle of measurement of several parameters are explained. The setup of the fiber PH sensor based on principle of light absorption is also introduced in detail and some experimental results are given. From the results we can see that the system can measure the PH value precisely suitable for cell cultivation. The linear and repeatable accuracies are 3.6% and 6.7% respectively, which can fulfill the measurement task.

  8. Pushing the frontiers of first-principles based computer simulations of chemical and biological systems.

    PubMed

    Brunk, Elizabeth; Ashari, Negar; Athri, Prashanth; Campomanes, Pablo; de Carvalho, F Franco; Curchod, Basile F E; Diamantis, Polydefkis; Doemer, Manuel; Garrec, Julian; Laktionov, Andrey; Micciarelli, Marco; Neri, Marilisa; Palermo, Giulia; Penfold, Thomas J; Vanni, Stefano; Tavernelli, Ivano; Rothlisberger, Ursula

    2011-01-01

    The Laboratory of Computational Chemistry and Biochemistry is active in the development and application of first-principles based simulations of complex chemical and biochemical phenomena. Here, we review some of our recent efforts in extending these methods to larger systems, longer time scales and increased accuracies. Their versatility is illustrated with a diverse range of applications, ranging from the determination of the gas phase structure of the cyclic decapeptide gramicidin S, to the study of G protein coupled receptors, the interaction of transition metal based anti-cancer agents with protein targets, the mechanism of action of DNA repair enzymes, the role of metal ions in neurodegenerative diseases and the computational design of dye-sensitized solar cells. Many of these projects are done in collaboration with experimental groups from the Institute of Chemical Sciences and Engineering (ISIC) at the EPFL.

  9. Earth's Earliest Ecosystems in the Classroom: The Use of Microbial Mats to Teach General Principles in Microbial Ecology, and Scientific Inquiry

    NASA Technical Reports Server (NTRS)

    Beboutl, Brad M.; Bucaria, Robin

    2004-01-01

    Microbial mats are living examples of the most ancient biological communities on earth, and may also be useful models for the search for life elsewhere. They are centrally important to Astrobiology. In this lecture, we will present an introduction to microbial mats, as well as an introduction to our web-based educational module on the subject of microbial ecology, featuring living mats maintained in a mini "Web Lab" complete with remotely-operable instrumentation. We have partnered with a number of outreach specialists in order to produce an informative and educational web-based presentation, aspects of which will be exported to museum exhibits reaching a wide audience. On our web site, we will conduct regularly scheduled experimental manipulations, linking the experiments to our research activities, and demonstrating fundamental principles of scientific research.

  10. Principles for the dynamic maintenance of cortical polarity

    PubMed Central

    Marco, Eugenio; Wedlich-Soldner, Roland; Li, Rong; Altschuler, Steven J.; Wu, Lani F.

    2007-01-01

    Summary Diverse cell types require the ability to dynamically maintain polarized membrane protein distributions through balancing transport and diffusion. However, design principles underlying dynamically maintained cortical polarity are not well understood. Here we constructed a mathematical model for characterizing the morphology of dynamically polarized protein distributions. We developed analytical approaches for measuring all model parameters from single-cell experiments. We applied our methods to a well-characterized system for studying polarized membrane proteins: budding yeast cells expressing activated Cdc42. We found that balanced diffusion and colocalized transport to and from the plasma membrane were sufficient for accurately describing polarization morphologies. Surprisingly, the model predicts that polarized regions are defined with a precision that is nearly optimal for measured transport rates, and that polarity can be dynamically stabilized through positive feedback with directed transport. Our approach provides a step towards understanding how biological systems shape spatially precise, unambiguous cortical polarity domains using dynamic processes. PMID:17448998

  11. Of Maggots Murder: Forensic Entomology in the Classroom.

    ERIC Educational Resources Information Center

    Carloye, Lisa

    2003-01-01

    Presents a hands-on lesson in biology in which students evaluate the evidence from four death scenarios. Students use knowledge of ecological principles, specifically ecological succession, and insect biology. Recommends three web sites related to the subject. (SOE)

  12. Perception of Mirror Symmetry in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Falter, Christine M.; Bailey, Anthony J.

    2012-01-01

    Gestalt grouping in autism spectrum disorders (ASD) is selectively impaired for certain organization principles but for not others. Symmetry is a fundamental Gestalt principle characterizing many biological shapes. Sensitivity to symmetry was tested using the Picture Symmetry Test, which requires finding symmetry lines on pictures. Individuals…

  13. Anti-Inflammatory Properties of Flavone di-C-Glycosides as Active Principles of Camellia Mistletoe, Korthalsella japonica

    PubMed Central

    Kim, Min Kyoung; Yun, Kwang Jun; Lim, Da Hae; Kim, Jinju; Jang, Young Pyo

    2016-01-01

    The chemical components and biological activity of Camellia mistletoe, Korthalsella japonica (Loranthaceae) are relatively unknown compared to other mistletoe species. Therefore, we investigated the phytochemical properties and biological activity of this parasitic plant to provide essential preliminary scientific evidence to support and encourage its further pharmaceutical research and development. The major plant components were chromatographically isolated using high-performance liquid chromatography and their structures were elucidated using tandem mass spectrometry and nuclear magnetic resonance anlysis. Furthermore, the anti-inflammatory activity of the 70% ethanol extract of K. japonica (KJ) and its isolated components was evaluated using a nitric oxide (NO) assay and western blot analysis for inducible NO synthase (iNOS) and cyclooxygenase (COX)-2. Three flavone di-C-glycosides, lucenin-2, vicenin-2, and stellarin-2 were identified as major components of KJ, for the first time. KJ significantly inhibited NO production and reduced iNOS and COX-2 expression in lipopolysaccharide-stimulated RAW 264.7 cells at 100 μg/mL while similar activity were observed with isolated flavone C-glycosides. In conclusion, KJ has a simple secondary metabolite profiles including flavone di-C-glycosides as major components and has a strong potential for further research and development as a source of therapeutic anti-inflammatory agents. PMID:27302962

  14. Usnic acid.

    PubMed

    Ingólfsdóttir, K

    2002-12-01

    Since its first isolation in 1844, usnic acid [2,6-diacetyl-7,9-dihydroxy-8,9b-dimethyl-1,3(2H,9bH)-dibenzo-furandione] has become the most extensively studied lichen metabolite and one of the few that is commercially available. Usnic acid is uniquely found in lichens, and is especially abundant in genera such as Alectoria, Cladonia, Usnea, Lecanora, Ramalina and Evernia. Many lichens and extracts containing usnic acid have been utilized for medicinal, perfumery, cosmetic as well as ecological applications. Usnic acid as a pure substance has been formulated in creams, toothpaste, mouthwash, deodorants and sunscreen products, in some cases as an active principle, in others as a preservative. In addition to antimicrobial activity against human and plant pathogens, usnic acid has been shown to exhibit antiviral, antiprotozoal, antiproliferative, anti-inflammatory and analgesic activity. Ecological effects, such as antigrowth, antiherbivore and anti-insect properties, have also been demonstrated. A difference in biological activity has in some cases been observed between the two enantiomeric forms of usnic acid. Recently health food supplements containing usnic acid have been promoted for use in weight reduction, with little scientific support. The emphasis of the current review is on the chemistry and biological activity of usnic acid and its derivatives in addition to rational and ecologically acceptable methods for provision of this natural compound on a large scale.

  15. Gingerols and shogaols: Important nutraceutical principles from ginger.

    PubMed

    Semwal, Ruchi Badoni; Semwal, Deepak Kumar; Combrinck, Sandra; Viljoen, Alvaro M

    2015-09-01

    Gingerols are the major pungent compounds present in the rhizomes of ginger (Zingiber officinale Roscoe) and are renowned for their contribution to human health and nutrition. Medicinal properties of ginger, including the alleviation of nausea, arthritis and pain, have been associated with the gingerols. Gingerol analogues are thermally labile and easily undergo dehydration reactions to form the corresponding shogaols, which impart the characteristic pungent taste to dried ginger. Both gingerols and shogaols exhibit a host of biological activities, ranging from anticancer, anti-oxidant, antimicrobial, anti-inflammatory and anti-allergic to various central nervous system activities. Shogaols are important biomarkers used for the quality control of many ginger-containing products, due to their diverse biological activities. In this review, a large body of available knowledge on the biosynthesis, chemical synthesis and pharmacological activities, as well as on the structure-activity relationships of various gingerols and shogaols, have been collated, coherently summarised and discussed. The manuscript highlights convincing evidence indicating that these phenolic compounds could serve as important lead molecules for the development of therapeutic agents to treat various life-threatening human diseases, particularly cancer. Inclusion of ginger or ginger extracts in nutraceutical formulations could provide valuable protection against diabetes, cardiac and hepatic disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. A Unifying Mathematical Framework for Genetic Robustness, Environmental Robustness, Network Robustness and their Trade-off on Phenotype Robustness in Biological Networks Part I: Gene Regulatory Networks in Systems and Evolutionary Biology

    PubMed Central

    Chen, Bor-Sen; Lin, Ying-Po

    2013-01-01

    Robust stabilization and environmental disturbance attenuation are ubiquitous systematic properties observed in biological systems at different levels. The underlying principles for robust stabilization and environmental disturbance attenuation are universal to both complex biological systems and sophisticated engineering systems. In many biological networks, network robustness should be enough to confer intrinsic robustness in order to tolerate intrinsic parameter fluctuations, genetic robustness for buffering genetic variations, and environmental robustness for resisting environmental disturbances. With this, the phenotypic stability of biological network can be maintained, thus guaranteeing phenotype robustness. This paper presents a survey on biological systems and then develops a unifying mathematical framework for investigating the principles of both robust stabilization and environmental disturbance attenuation in systems and evolutionary biology. Further, from the unifying mathematical framework, it was discovered that the phenotype robustness criterion for biological networks at different levels relies upon intrinsic robustness + genetic robustness + environmental robustness ≦ network robustness. When this is true, the phenotype robustness can be maintained in spite of intrinsic parameter fluctuations, genetic variations, and environmental disturbances. Therefore, the trade-offs between intrinsic robustness, genetic robustness, environmental robustness, and network robustness in systems and evolutionary biology can also be investigated through their corresponding phenotype robustness criterion from the systematic point of view. PMID:23515240

  17. A Unifying Mathematical Framework for Genetic Robustness, Environmental Robustness, Network Robustness and their Trade-off on Phenotype Robustness in Biological Networks Part I: Gene Regulatory Networks in Systems and Evolutionary Biology.

    PubMed

    Chen, Bor-Sen; Lin, Ying-Po

    2013-01-01

    Robust stabilization and environmental disturbance attenuation are ubiquitous systematic properties observed in biological systems at different levels. The underlying principles for robust stabilization and environmental disturbance attenuation are universal to both complex biological systems and sophisticated engineering systems. In many biological networks, network robustness should be enough to confer intrinsic robustness in order to tolerate intrinsic parameter fluctuations, genetic robustness for buffering genetic variations, and environmental robustness for resisting environmental disturbances. With this, the phenotypic stability of biological network can be maintained, thus guaranteeing phenotype robustness. This paper presents a survey on biological systems and then develops a unifying mathematical framework for investigating the principles of both robust stabilization and environmental disturbance attenuation in systems and evolutionary biology. Further, from the unifying mathematical framework, it was discovered that the phenotype robustness criterion for biological networks at different levels relies upon intrinsic robustness + genetic robustness + environmental robustness ≦ network robustness. When this is true, the phenotype robustness can be maintained in spite of intrinsic parameter fluctuations, genetic variations, and environmental disturbances. Therefore, the trade-offs between intrinsic robustness, genetic robustness, environmental robustness, and network robustness in systems and evolutionary biology can also be investigated through their corresponding phenotype robustness criterion from the systematic point of view.

  18. Maximum entropy models as a tool for building precise neural controls.

    PubMed

    Savin, Cristina; Tkačik, Gašper

    2017-10-01

    Neural responses are highly structured, with population activity restricted to a small subset of the astronomical range of possible activity patterns. Characterizing these statistical regularities is important for understanding circuit computation, but challenging in practice. Here we review recent approaches based on the maximum entropy principle used for quantifying collective behavior in neural activity. We highlight recent models that capture population-level statistics of neural data, yielding insights into the organization of the neural code and its biological substrate. Furthermore, the MaxEnt framework provides a general recipe for constructing surrogate ensembles that preserve aspects of the data, but are otherwise maximally unstructured. This idea can be used to generate a hierarchy of controls against which rigorous statistical tests are possible. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. WormClassroom.org: An Inquiry-Rich Educational Web Portal for Research Resources of "Caenorhabditis elegans"

    ERIC Educational Resources Information Center

    Lu, Fong-Mei; Eliceiri, Kevin W.; Stewart, James; White, John G.

    2007-01-01

    The utilization of biology research resources, coupled with a "learning by inquiry" approach, has great potential to aid students in gaining an understanding of fundamental biological principles. To help realize this potential, we have developed a Web portal for undergraduate biology education, WormClassroom.org, based on current research…

  20. "Sickle Cell Anemia: Tracking down a Mutation": An Interactive Learning Laboratory That Communicates Basic Principles of Genetics and Cellular Biology

    ERIC Educational Resources Information Center

    Jarrett, Kevin; Williams, Mary; Horn, Spencer; Radford, David; Wyss, J. Michael

    2016-01-01

    "Sickle cell anemia: tracking down a mutation" is a full-day, inquiry-based, biology experience for high school students enrolled in genetics or advanced biology courses. In the experience, students use restriction endonuclease digestion, cellulose acetate gel electrophoresis, and microscopy to discover which of three putative patients…

  1. BIOLOGY I, NEW APPROACHES AND OBJECTIVES.

    ERIC Educational Resources Information Center

    COKER, ROBERT; AND OTHERS

    THE PRINCIPLES OF MODERN BIOLOGY SHOULD BE PRESENTED IN A DYNAMIC AND CHALLENGING WAY TO CAPABLE STUDENTS TO DEVELOP LASTING INTEREST IN THE SUBJECT AND TO PLACE EMPHASIS UPON THE ROLE OF THE PHYSICAL SCIENCES IN BIOLOGY IN ACCORD WITH NATIONWIDE TENDENCY. THE COURSE IS COMPLETE IN ITSELF BUT PROVIDES A BASIS FOR STUDENTS WHO ELECT ADVANCED WORK.…

  2. Light-sensitive Lipid-based Nanoparticles for Drug Delivery: Design Principles and Future Considerations for Biological Applications

    PubMed Central

    Yavlovich, Amichai; Smith, Brandon; Gupta, Kshitij; Blumenthal, Robert; Puri, Anu

    2011-01-01

    Radiation-based therapies aided by nanoparticles have been developed since decades, and can be primarily categorized into two main platforms. First, delivery of payload of photo-reactive drugs (photosensitizers) using the conventional nanoparticles, and second, design and development of photo-triggerable nanoparticles (primarily liposomes) to attain light-assisted on-demand drug delivery. The main focus of this review is to provide an update of the history, current status and future applications of photo-triggerable lipid-based nanoparticles (light-sensitive liposomes). We will begin with a brief overview on the applications of liposomes for delivery of photosensitizers, including the choice of photosensitizers for photodynamic therapy, as well as the currently available light sources (lasers) used for these applications. The main segment of this review will encompass the details on the strategies to develop photo-triggerable designer liposomes for their drug delivery function. The principles underlying the assembly of photoreactive lipids into nanoparticles (liposomes) and photo-triggering mechanisms will be presented. We will also discuss factors that limit the applications of these liposomes for in vivo triggered drug delivery and emerging concepts that may lead to the biologically viable photo-activation strategies. We will conclude with our view point on the future perspectives of light-sensitive liposomes in the clinic. PMID:20939770

  3. Strategic alliance as a competitive tactics for biological-pharmacy industry.

    PubMed

    Liu, Chuanming; Wang, Ling; Qi, Ershi

    2005-01-01

    Biological-pharmacy industry refers to biotechnology companies and pharmacy makers. Because of the uncertainty and time-lag in the field of biological-pharmacy, the former is confronted with lacking of capital and the later is faced with improving technique-innovation and product-exploitation. This paper analyzes basic operation principle of strategic alliance, and related strategies are also put forward for biological-pharmacy enterprise to carry out.

  4. Starlings uphold principles of economic rationality for delay and probability of reward.

    PubMed

    Monteiro, Tiago; Vasconcelos, Marco; Kacelnik, Alex

    2013-04-07

    Rationality principles are the bedrock of normative theories of decision-making in biology and microeconomics, but whereas in microeconomics, consistent choice underlies the notion of utility; in biology, the assumption of consistent selective pressures justifies modelling decision mechanisms as if they were designed to maximize fitness. In either case, violations of consistency contradict expectations and attract theoretical interest. Reported violations of rationality in non-humans include intransitivity (i.e. circular preferences) and lack of independence of irrelevant alternatives (changes in relative preference between options when embedded in different choice sets), but the extent to which these observations truly represent breaches of rationality is debatable. We tested both principles with starlings (Sturnus vulgaris), training subjects either with five options differing in food delay (exp. 1) or with six options differing in reward probability (exp. 2), before letting them choose repeatedly one option out of several binary and trinary sets of options. The starlings conformed to economic rationality on both tests, showing strong stochastic transitivity and no violation of the independence principle. These results endorse the rational choice and optimality approaches used in behavioural ecology, and highlight the need for functional and mechanistic enquiring when apparent violations of such principles are observed.

  5. Starlings uphold principles of economic rationality for delay and probability of reward

    PubMed Central

    Monteiro, Tiago; Vasconcelos, Marco; Kacelnik, Alex

    2013-01-01

    Rationality principles are the bedrock of normative theories of decision-making in biology and microeconomics, but whereas in microeconomics, consistent choice underlies the notion of utility; in biology, the assumption of consistent selective pressures justifies modelling decision mechanisms as if they were designed to maximize fitness. In either case, violations of consistency contradict expectations and attract theoretical interest. Reported violations of rationality in non-humans include intransitivity (i.e. circular preferences) and lack of independence of irrelevant alternatives (changes in relative preference between options when embedded in different choice sets), but the extent to which these observations truly represent breaches of rationality is debatable. We tested both principles with starlings (Sturnus vulgaris), training subjects either with five options differing in food delay (exp. 1) or with six options differing in reward probability (exp. 2), before letting them choose repeatedly one option out of several binary and trinary sets of options. The starlings conformed to economic rationality on both tests, showing strong stochastic transitivity and no violation of the independence principle. These results endorse the rational choice and optimality approaches used in behavioural ecology, and highlight the need for functional and mechanistic enquiring when apparent violations of such principles are observed. PMID:23390098

  6. Neurons for hunger and thirst transmit a negative-valence teaching signal.

    PubMed

    Betley, J Nicholas; Xu, Shengjin; Cao, Zhen Fang Huang; Gong, Rong; Magnus, Christopher J; Yu, Yang; Sternson, Scott M

    2015-05-14

    Homeostasis is a biological principle for regulation of essential physiological parameters within a set range. Behavioural responses due to deviation from homeostasis are critical for survival, but motivational processes engaged by physiological need states are incompletely understood. We examined motivational characteristics of two separate neuron populations that regulate energy and fluid homeostasis by using cell-type-specific activity manipulations in mice. We found that starvation-sensitive AGRP neurons exhibit properties consistent with a negative-valence teaching signal. Mice avoided activation of AGRP neurons, indicating that AGRP neuron activity has negative valence. AGRP neuron inhibition conditioned preference for flavours and places. Correspondingly, deep-brain calcium imaging revealed that AGRP neuron activity rapidly reduced in response to food-related cues. Complementary experiments activating thirst-promoting neurons also conditioned avoidance. Therefore, these need-sensing neurons condition preference for environmental cues associated with nutrient or water ingestion, which is learned through reduction of negative-valence signals during restoration of homeostasis.

  7. Clarity of objectives and working principles enhances the success of biomimetic programs.

    PubMed

    Wolff, Jonas O; Wells, David; Reid, Chris R; Blamires, Sean J

    2017-09-26

    Biomimetics, the transfer of functional principles from living systems into product designs, is increasingly being utilized by engineers. Nevertheless, recurring problems must be overcome if it is to avoid becoming a short-lived fad. Here we assess the efficiency and suitability of methods typically employed by examining three flagship examples of biomimetic design approaches from different disciplines: (1) the creation of gecko-inspired adhesives; (2) the synthesis of spider silk, and (3) the derivation of computer algorithms from natural self-organizing systems. We find that identification of the elemental working principles is the most crucial step in the biomimetic design process. It bears the highest risk of failure (e.g. losing the target function) due to false assumptions about the working principle. Common problems that hamper successful implementation are: (i) a discrepancy between biological functions and the desired properties of the product, (ii) uncertainty about objectives and applications, (iii) inherent limits in methodologies, and (iv) false assumptions about the biology of the models. Projects that aim for multi-functional products are particularly challenging to accomplish. We suggest a simplification, modularisation and specification of objectives, and a critical assessment of the suitability of the model. Comparative analyses, experimental manipulation, and numerical simulations followed by tests of artificial models have led to the successful extraction of working principles. A searchable database of biological systems would optimize the choice of a model system in top-down approaches that start at an engineering problem. Only when biomimetic projects become more predictable will there be wider acceptance of biomimetics as an innovative problem-solving tool among engineers and industry.

  8. Prokaryotic regulatory systems biology: Common principles governing the functional architectures of Bacillus subtilis and Escherichia coli unveiled by the natural decomposition approach.

    PubMed

    Freyre-González, Julio A; Treviño-Quintanilla, Luis G; Valtierra-Gutiérrez, Ilse A; Gutiérrez-Ríos, Rosa María; Alonso-Pavón, José A

    2012-10-31

    Escherichia coli and Bacillus subtilis are two of the best-studied prokaryotic model organisms. Previous analyses of their transcriptional regulatory networks have shown that they exhibit high plasticity during evolution and suggested that both converge to scale-free-like structures. Nevertheless, beyond this suggestion, no analyses have been carried out to identify the common systems-level components and principles governing these organisms. Here we show that these two phylogenetically distant organisms follow a set of common novel biologically consistent systems principles revealed by the mathematically and biologically founded natural decomposition approach. The discovered common functional architecture is a diamond-shaped, matryoshka-like, three-layer (coordination, processing, and integration) hierarchy exhibiting feedback, which is shaped by four systems-level components: global transcription factors (global TFs), locally autonomous modules, basal machinery and intermodular genes. The first mathematical criterion to identify global TFs, the κ-value, was reassessed on B. subtilis and confirmed its high predictive power by identifying all the previously reported, plus three potential, master regulators and eight sigma factors. The functionally conserved cores of modules, basal cell machinery, and a set of non-orthologous common physiological global responses were identified via both orthologous genes and non-orthologous conserved functions. This study reveals novel common systems principles maintained between two phylogenetically distant organisms and provides a comparison of their lifestyle adaptations. Our results shed new light on the systems-level principles and the fundamental functions required by bacteria to sustain life. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. In search of a metatheory for cognitive development (or, Piaget is dead and I don't feel so good myself).

    PubMed

    Bjorklund, D F

    1997-02-01

    With the waning of influence of Piaget's theory and the shortcomings of information-processing perspectives of cognitive growth, cognitive developmentalists lack a common set of broad, overarching principles and assumptions--a metatheory--to guide their research. Developmental biology is suggested as metatheory for cognitive development. Although it is important for developmentalists to understand proximal biological causes (e.g., brain development), most important for such a metatheory is an evolutionary perspective. Some basic principles of evolutionary psychology are introduced, and examples of contemporary research and theory consistent with these ideas are provided.

  10. Feedback in Action--The Mechanism of the Iris.

    ERIC Educational Resources Information Center

    Pingnet, B.; And Others

    1988-01-01

    Describes two demonstration experiments. Outlines a demonstration of the general principle of positive and negative feedback and the influence of time delays in feedback circuits. Elucidates the principle of negative feedback with a model of the iris of the eye. Emphasizes the importance of feedback in biological systems. (CW)

  11. Seeing the Unseen

    ERIC Educational Resources Information Center

    Turner, Kenneth; Tevaarwerk, Emma; Unterman, Nathan; Grdinic, Marcel; Campbell, Jason; Chandrasekhar, Venkat; Chang, R. P. H.

    2006-01-01

    Nanoscience refers to the fundamental study of scientific phenomena, which occur at the nanoscale--nanotechnology to the exploitation of novel properties and functions of materials in the sub-100 nm size range. One of the underlying principles of science is development of models of observed phenomena. In biology, the Hardy-Weinberg principle is a…

  12. The "F" Factor: Feminism Forsaken?

    ERIC Educational Resources Information Center

    McLoughlin, A.

    1997-01-01

    Suggests feminist principles relevant to midwifery include affirmation of equal rights; derivation of individuals' value from their capacity to contribute to society, not from biology; and accordance to women of the same rights over their bodies as men have over theirs. Notes feminist theory and principles should underlie midwifery education and…

  13. Understanding Phylogenies in Biology: The Influence of a Gestalt Perceptual Principle

    ERIC Educational Resources Information Center

    Novick, Laura R.; Catley, Kefyn M.

    2007-01-01

    Cladograms, hierarchical diagrams depicting evolutionary histories among (groups of) species, are commonly drawn in 2 informationally equivalent formats--tree and ladder. The authors hypothesize that these formats are not computationally equivalent because the Gestalt principle of good continuation obscures the hierarchical structure of ladders.…

  14. Contemporary treatment principles for early rheumatoid arthritis: a consensus statement.

    PubMed

    Kiely, Patrick D W; Brown, Andrew K; Edwards, Christopher J; O'Reilly, David T; Ostör, Andrew J K; Quinn, Mark; Taggart, Allister; Taylor, Peter C; Wakefield, Richard J; Conaghan, Philip G

    2009-07-01

    RA has a substantial impact on both patients and healthcare systems. Our objective is to advance the understanding of modern management principles in light of recent evidence concerning the condition's diagnosis and treatment. A group of practicing UK rheumatologists formulated contemporary management principles and clinical practice recommendations concerning both diagnosis and treatment. Areas of clinical uncertainty were documented, leading to research recommendations. A fundamental concept governing treatment of RA is minimization of cumulative inflammation, referred to as the inflammation-time area under the curve (AUC). To achieve this, four core principles of management were identified: (i) detect and refer patients early, even if the diagnosis is uncertain: patients should be referred at the first suspicion of persistent inflammatory polyarthritis and rheumatology departments should provide rapid access to a diagnostic and prognostic service; (ii) treat RA immediately: optimizing outcomes with conventional DMARDs and biologics requires that effective treatment be started early-ideally within 3 months of symptom onset; (iii) tight control of inflammation in RA improves outcome: frequent assessments and an objective protocol should be used to make treatment changes that maintain low-disease activity/remission at an agreed target; (iv) consider the risk-benefit ratio and tailor treatment to each patient: differing patient, disease and drug characteristics require long-term monitoring of risks and benefits with adaptations of treatments to suit individual circumstances. These principles focus on effective control of the inflammatory process in RA, but optimal uptake may require changes in service provision to accommodate appropriate care pathways.

  15. Chemical, biological, radiological, and nuclear decontamination: Recent trends and future perspective

    PubMed Central

    Kumar, Vinod; Goel, Rajeev; Chawla, Raman; Silambarasan, M.; Sharma, Rakesh Kumar

    2010-01-01

    Chemical, biological, radiological, and nuclear (CBRN) decontamination is the removal of CBRN material from equipment or humans. The objective of the decontamination is to reduce radiation burden, salvage equipment, and materials, remove loose CBRN contaminants, and fix the remaining in place in preparation for protective storage or permanent disposal work activities. Decontamination may be carried out using chemical, electrochemical, and mechanical means. Like materials, humans may also be contaminated with CBRN contamination. Changes in cellular function can occur at lower radiation doses and exposure to chemicals. At high dose, cell death may take place. Therefore, decontamination of humans at the time of emergency while generating bare minimum waste is an enormous task requiring dedication of large number of personnel and large amount of time. General principles of CBRN decontamination are discussed in this review with emphasis on radiodecontamination. PMID:21829318

  16. The biology of mammalian parenting and its effect on offspring social development.

    PubMed

    Rilling, James K; Young, Larry J

    2014-08-15

    Parents know the transformative nature of having and caring for a child. Among many mammals, giving birth leads from an aversion to infant stimuli to irresistible attraction. Here, we review the biological mechanisms governing this shift in parental motivation in mammals. Estrogen and progesterone prepare the uterus for embryo implantation and placental development. Prolactin stimulates milk production, whereas oxytocin initiates labor and triggers milk ejection during nursing. These same molecules, interacting with dopamine, also activate specific neural pathways to motivate parents to nurture, bond with, and protect their offspring. Parenting in turn shapes the neural development of the infant social brain. Recent work suggests that many of the principles governing parental behavior and its effect on infant development are conserved from rodent to humans. Copyright © 2014, American Association for the Advancement of Science.

  17. Notable Expressions: Transcriptional Regulation from Biochemistry to Immunology | Center for Cancer Research

    Cancer.gov

    Dinah Singer, Ph.D., came to NCI in 1975 as a Postdoctoral Fellow in the Laboratory of Biochemistry, but soon created a career for herself in the Experimental Immunology Branch. Her interest in how genes are regulated to control biological function led her to focus on major histocompatibility complex class I genes (MHC Class I)—molecules critical to immune system function—as a model system for complex regulation of ubiquitously expressed genes across cell types and molecular contexts. Using this system to study the sequence elements and factors that control transcription, her laboratory continues to uncover fundamental principles of gene regulation. In addition to her active research career, Singer has served since 1999 as Director of NCI’s Division of Cancer Biology, which manages a portfolio of over 2,200 grants to extramural investigators.

  18. Environmental ethics: an overview, assessing the place of bioscientists in society, supplemented with selected Australian perspectives.

    PubMed

    Buckeridge, John

    2014-01-01

    Ethics deals with moral behavior in a professional context; ideally, it leads to a set of governing principles through which the appropriateness of any activity may be determined or assessed. Environmental ethics specifically deals with how humans interact with the biosphere. It is clear, however, that, as a species, we are failing in our duty of environmental stewardship. The encroachment of human activity into the natural environment is inexorable, and almost always deleterious. Any response to mitigate loss of taxa or ecosystems will have economic implications, and these are often considerable. In finding effective solutions, a process soon becomes political. In light of this we must reflect upon the leadership role that biologists have, especially our impact on policy development that pertains to natural resource management. Although our track record is no worse than any other professional group, biologists by way of training usually have a greater understanding of natural processes and must be prepared to articulate these publically. We have an ethical mandate to question decisions, policies and legislation that impact negatively upon biological systems: a mandate guided through logic, grounded in empirical science, and hopefully coupled with a deep understanding of the true value of both the living world and the physical world which sustains it. This paper uses Australian examples to demonstrate the frequent clashes between economics and biology, in anticipation that we should strive to achieve the underlying principles of sustainability, environmental stewardship and resource management in both daily decision-making and in long-term planning. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  19. Vision of Fish in Air

    ERIC Educational Resources Information Center

    Colicchia, Giuseppe

    2007-01-01

    The investigation of the focusing in fish eyes, both theoretical and experimental, by using a simple fish eye model, provides an interesting biological context for teaching the introductory principles of optics. Moreover, the students will learn concepts of biology by an approach of cause and effect.

  20. Transforming Introductory Physics for Life Scientists: Researching the consequences for students

    NASA Astrophysics Data System (ADS)

    Turpen, Chandra

    2011-10-01

    In response to policy documents calling for dramatic changes in pre-medical and biology education [1-3], the physics and biology education research groups at the University of Maryland are rethinking how to teach physics to life science majors. As an interdisciplinary team, we are drastically reconsidering the physics topics relevant for these courses. We are designing new in-class tasks to engage students in using physical principles to explain aspects of biological phenomena where the physical principles are of consequence to the biological systems. We will present examples of such tasks as well as preliminary data on how students engage in these tasks. Lastly, we will share some barriers encountered in pursuing meaningful interdisciplinary education.[4pt] Co-authors: Edward F. Redish and Julia Svaboda [4pt] [1] National Research Council, Bio2010: Transforming Undergraduate Education for Future Research Biologists (NAP, 2003).[0pt] [2] AAMC-HHMI committee, Scientific Foundations for Future Physicians (AAMC, 2009).[0pt] [3] American Association for the Advancement of Science, Vision and Change in Undergraduate Biology Education: A Call to Action (AAAS, 2009).

  1. Distance-dependent magnetic resonance tuning as a versatile MRI sensing platform for biological targets

    NASA Astrophysics Data System (ADS)

    Choi, Jin-Sil; Kim, Soojin; Yoo, Dongwon; Shin, Tae-Hyun; Kim, Hoyoung; Gomes, Muller D.; Kim, Sun Hee; Pines, Alexander; Cheon, Jinwoo

    2017-05-01

    Nanoscale distance-dependent phenomena, such as Förster resonance energy transfer, are important interactions for use in sensing and imaging, but their versatility for bioimaging can be limited by undesirable photon interactions with the surrounding biological matrix, especially in in vivo systems. Here, we report a new type of magnetism-based nanoscale distance-dependent phenomenon that can quantitatively and reversibly sense and image intra-/intermolecular interactions of biologically important targets. We introduce distance-dependent magnetic resonance tuning (MRET), which occurs between a paramagnetic `enhancer' and a superparamagnetic `quencher', where the T1 magnetic resonance imaging (MRI) signal is tuned ON or OFF depending on the separation distance between the quencher and the enhancer. With MRET, we demonstrate the principle of an MRI-based ruler for nanometre-scale distance measurement and the successful detection of both molecular interactions (for example, cleavage, binding, folding and unfolding) and biological targets in in vitro and in vivo systems. MRET can serve as a novel sensing principle to augment the exploration of a wide range of biological systems.

  2. Rewiring cells: synthetic biology as a tool to interrogate the organizational principles of living systems.

    PubMed

    Bashor, Caleb J; Horwitz, Andrew A; Peisajovich, Sergio G; Lim, Wendell A

    2010-01-01

    The living cell is an incredibly complex entity, and the goal of predictively and quantitatively understanding its function is one of the next great challenges in biology. Much of what we know about the cell concerns its constituent parts, but to a great extent we have yet to decode how these parts are organized to yield complex physiological function. Classically, we have learned about the organization of cellular networks by disrupting them through genetic or chemical means. The emerging discipline of synthetic biology offers an additional, powerful approach to study systems. By rearranging the parts that comprise existing networks, we can gain valuable insight into the hierarchical logic of the networks and identify the modular building blocks that evolution uses to generate innovative function. In addition, by building minimal toy networks, one can systematically explore the relationship between network structure and function. Here, we outline recent work that uses synthetic biology approaches to investigate the organization and function of cellular networks, and describe a vision for a synthetic biology toolkit that could be used to interrogate the design principles of diverse systems.

  3. Enzymatically Active Microgels from Self-Assembling Protein Nanofibrils for Microflow Chemistry.

    PubMed

    Zhou, Xiao-Ming; Shimanovich, Ulyana; Herling, Therese W; Wu, Si; Dobson, Christopher M; Knowles, Tuomas P J; Perrett, Sarah

    2015-06-23

    Amyloid fibrils represent a generic class of protein structure associated with both pathological states and with naturally occurring functional materials. This class of protein nanostructure has recently also emerged as an excellent foundation for sophisticated functional biocompatible materials including scaffolds and carriers for biologically active molecules. Protein-based materials offer the potential advantage that additional functions can be directly incorporated via gene fusion producing a single chimeric polypeptide that will both self-assemble and display the desired activity. To succeed, a chimeric protein system must self-assemble without the need for harsh triggering conditions which would damage the appended functional protein molecule. However, the micrometer to nanoscale patterning and morphological control of protein-based nanomaterials has remained challenging. This study demonstrates a general approach for overcoming these limitations through the microfluidic generation of enzymatically active microgels that are stabilized by amyloid nanofibrils. The use of scaffolds formed from biomaterials that self-assemble under mild conditions enables the formation of catalytic microgels while maintaining the integrity of the encapsulated enzyme. The enzymatically active microgel particles show robust material properties and their porous architecture allows diffusion in and out of reactants and products. In combination with microfluidic droplet trapping approaches, enzymatically active microgels illustrate the potential of self-assembling materials for enzyme immobilization and recycling, and for biological flow-chemistry. These design principles can be adopted to create countless other bioactive amyloid-based materials with diverse functions.

  4. Towards the understanding of network information processing in biology

    NASA Astrophysics Data System (ADS)

    Singh, Vijay

    Living organisms perform incredibly well in detecting a signal present in the environment. This information processing is achieved near optimally and quite reliably, even though the sources of signals are highly variable and complex. The work in the last few decades has given us a fair understanding of how individual signal processing units like neurons and cell receptors process signals, but the principles of collective information processing on biological networks are far from clear. Information processing in biological networks, like the brain, metabolic circuits, cellular-signaling circuits, etc., involves complex interactions among a large number of units (neurons, receptors). The combinatorially large number of states such a system can exist in makes it impossible to study these systems from the first principles, starting from the interactions between the basic units. The principles of collective information processing on such complex networks can be identified using coarse graining approaches. This could provide insights into the organization and function of complex biological networks. Here I study models of biological networks using continuum dynamics, renormalization, maximum likelihood estimation and information theory. Such coarse graining approaches identify features that are essential for certain processes performed by underlying biological networks. We find that long-range connections in the brain allow for global scale feature detection in a signal. These also suppress the noise and remove any gaps present in the signal. Hierarchical organization with long-range connections leads to large-scale connectivity at low synapse numbers. Time delays can be utilized to separate a mixture of signals with temporal scales. Our observations indicate that the rules in multivariate signal processing are quite different from traditional single unit signal processing.

  5. Defining functional DNA elements in the human genome

    PubMed Central

    Kellis, Manolis; Wold, Barbara; Snyder, Michael P.; Bernstein, Bradley E.; Kundaje, Anshul; Marinov, Georgi K.; Ward, Lucas D.; Birney, Ewan; Crawford, Gregory E.; Dekker, Job; Dunham, Ian; Elnitski, Laura L.; Farnham, Peggy J.; Feingold, Elise A.; Gerstein, Mark; Giddings, Morgan C.; Gilbert, David M.; Gingeras, Thomas R.; Green, Eric D.; Guigo, Roderic; Hubbard, Tim; Kent, Jim; Lieb, Jason D.; Myers, Richard M.; Pazin, Michael J.; Ren, Bing; Stamatoyannopoulos, John A.; Weng, Zhiping; White, Kevin P.; Hardison, Ross C.

    2014-01-01

    With the completion of the human genome sequence, attention turned to identifying and annotating its functional DNA elements. As a complement to genetic and comparative genomics approaches, the Encyclopedia of DNA Elements Project was launched to contribute maps of RNA transcripts, transcriptional regulator binding sites, and chromatin states in many cell types. The resulting genome-wide data reveal sites of biochemical activity with high positional resolution and cell type specificity that facilitate studies of gene regulation and interpretation of noncoding variants associated with human disease. However, the biochemically active regions cover a much larger fraction of the genome than do evolutionarily conserved regions, raising the question of whether nonconserved but biochemically active regions are truly functional. Here, we review the strengths and limitations of biochemical, evolutionary, and genetic approaches for defining functional DNA segments, potential sources for the observed differences in estimated genomic coverage, and the biological implications of these discrepancies. We also analyze the relationship between signal intensity, genomic coverage, and evolutionary conservation. Our results reinforce the principle that each approach provides complementary information and that we need to use combinations of all three to elucidate genome function in human biology and disease. PMID:24753594

  6. Nontrivial Quantum Effects in Biology: A Skeptical Physicists' View

    NASA Astrophysics Data System (ADS)

    Wiseman, Howard; Eisert, Jens

    The following sections are included: * Introduction * A Quantum Life Principle * A quantum chemistry principle? * The anthropic principle * Quantum Computing in the Brain * Nature did everything first? * Decoherence as the make or break issue * Quantum error correction * Uselessness of quantum algorithms for organisms * Quantum Computing in Genetics * Quantum search * Teleological aspects and the fast-track to life * Quantum Consciousness * Computability and free will * Time scales * Quantum Free Will * Predictability and free will * Determinism and free will * Acknowledgements * References

  7. Advanced techniques in placental biology -- workshop report.

    PubMed

    Nelson, D M; Sadovsky, Y; Robinson, J M; Croy, B A; Rice, G; Kniss, D A

    2006-04-01

    Major advances in placental biology have been realized as new technologies have been developed and existing methods have been refined in many areas of biological research. Classical anatomy and whole-organ physiology tools once used to analyze placental structure and function have been supplanted by more sophisticated techniques adapted from molecular biology, proteomics, and computational biology and bioinformatics. In addition, significant refinements in morphological study of the placenta and its constituent cell types have improved our ability to assess form and function in highly integrated manner. To offer an overview of modern technologies used by investigators to study the placenta, this workshop: Advanced techniques in placental biology, assembled experts who discussed fundamental principles and real time examples of four separate methodologies. Y. Sadovsky presented the principles of microRNA function as an endogenous mechanism of gene regulation. J. Robinson demonstrated the utility of correlative microscopy in which light-level and transmission electron microscopy are combined to provide cellular and subcellular views of placental cells. A. Croy provided a lecture on the use of microdissection techniques which are invaluable for isolating very small subsets of cell types for molecular analysis. Finally, G. Rice presented an overview methods on profiling of complex protein mixtures within tissue and/or fluid samples that, when refined, will offer databases that will underpin a systems approach to modern trophoblast biology.

  8. Biologic relativity: Who is the observer and what is observed?

    PubMed

    Torday, John S; Miller, William B

    2016-05-01

    When quantum physics and biological phenomena are analogously explored, it emerges that biologic causation must also be understood independently of its overt appearance. This is similar to the manner in which Bohm characterized the explicate versus the implicate order as overlapping frames of ambiguity. Placed in this context, the variables affecting epigenetic inheritance can be properly assessed as a key mechanistic principle of evolution that significantly alters our understanding of homeostasis, pleiotropy, and heterochrony, and the purposes of sexual reproduction. Each of these become differing manifestations of a new biological relativity in which biologic space-time becomes its own frame. In such relativistic cellular contexts, it is proper to question exactly who has observer status, and who and what are being observed. Consideration within this frame reduces biology to cellular information sharing through cell-cell communication to resolve ambiguities at every scope and scale. In consequence, it becomes implicit that eukaryotic evolution derives from the unicellular state, remaining consistently adherent to it in a continuous evolutionary arc based upon elemental, non-stochastic physiologic first principles. Furthermore, the entire cell including its cytoskeletal apparatus and membranes that participate in the resolution of biological uncertainties must be considered as having equivalent primacy with genomes in evolutionary terms. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Does the Modality Principle for Multimedia Learning Apply to Science Classrooms?

    ERIC Educational Resources Information Center

    Harskamp, Egbert G.; Mayer, Richard E.; Suhre, Cor

    2007-01-01

    This study demonstrated that the modality principle applies to multimedia learning of regular science lessons in school settings. In the first field experiment, 27 Dutch secondary school students (age 16-17) received a self-paced, web-based multimedia lesson in biology. Students who received lessons containing illustrations and narration performed…

  10. Compression as a Universal Principle of Animal Behavior

    ERIC Educational Resources Information Center

    Ferrer-i-Cancho, Ramon; Hernández-Fernández, Antoni; Lusseau, David; Agoramoorthy, Govindasamy; Hsu, Minna J.; Semple, Stuart

    2013-01-01

    A key aim in biology and psychology is to identify fundamental principles underpinning the behavior of animals, including humans. Analyses of human language and the behavior of a range of non-human animal species have provided evidence for a common pattern underlying diverse behavioral phenomena: Words follow Zipf's law of brevity (the…

  11. The principles, definition and dimensions of the new nutrition science.

    PubMed

    Beauman, Christopher; Cannon, Geoffrey; Elmadfa, Ibrahim; Glasauer, Peter; Hoffmann, Ingrid; Keller, Markus; Krawinkel, Michael; Lang, Tim; Leitzmann, Claus; Lötsch, Bernd; Margetts, Barrie M; McMichael, Anthony J; Meyer-Abich, Klaus; Oltersdorf, Ulrich; Pettoello-Mantovani, Massimo; Sabaté, Joan; Shetty, Prakash; Sória, Marco; Spiekermann, Uwe; Tudge, Colin; Vorster, Hester H; Wahlqvist, Mark; Zerilli-Marimò, Mariuccia

    2005-09-01

    To specify the principles, definition and dimensions of the new nutrition science. To identify nutrition, with its application in food and nutrition policy, as a science with great width and breadth of vision and scope, in order that it can fully contribute to the preservation, maintenance, development and sustenance of life on Earth. A brief overview shows that current conventional nutrition is defined as a biological science, although its governing and guiding principles are implicit only, and no generally agreed definition is evident. Following are agreements on the principles, definition and dimensions of the new nutrition science, made by the authors as participants at a workshop on this theme held on 5-8 April 2005 at the Schloss Rauischholzhausen, Justus-Liebig University, Giessen, Germany. Nutrition science as here specified will retain its current 'classical' identity as a biological science, within a broader and integrated conceptual framework, and will also be confirmed as a social and environmental science. As such it will be concerned with personal and population health, and with planetary health--the welfare and future of the whole physical and living world of which humans are a part.

  12. The biological default state of cell proliferation with variation and motility, a fundamental principle for a theory of organisms.

    PubMed

    Soto, Ana M; Longo, Giuseppe; Montévil, Maël; Sonnenschein, Carlos

    2016-10-01

    The principle of inertia is central to the modern scientific revolution. By postulating this principle Galileo at once identified a pertinent physical observable (momentum) and a conservation law (momentum conservation). He then could scientifically analyze what modifies inertial movement: gravitation and friction. Inertia, the default state in mechanics, represented a major theoretical commitment: there is no need to explain uniform rectilinear motion, rather, there is a need to explain departures from it. By analogy, we propose a biological default state of proliferation with variation and motility. From this theoretical commitment, what requires explanation is proliferative quiescence, lack of variation, lack of movement. That proliferation is the default state is axiomatic for biologists studying unicellular organisms. Moreover, it is implied in Darwin's "descent with modification". Although a "default state" is a theoretical construct and a limit case that does not need to be instantiated, conditions that closely resemble unrestrained cell proliferation are readily obtained experimentally. We will illustrate theoretical and experimental consequences of applying and of ignoring this principle. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Deciphering principles of transcription regulation in eukaryotic genomes

    PubMed Central

    Nguyen, Dat H; D'haeseleer, Patrik

    2006-01-01

    Transcription regulation has been responsible for organismal complexity and diversity in the course of biological evolution and adaptation, and it is determined largely by the context-dependent behavior of cis-regulatory elements (CREs). Therefore, understanding principles underlying CRE behavior in regulating transcription constitutes a fundamental objective of quantitative biology, yet these remain poorly understood. Here we present a deterministic mathematical strategy, the motif expression decomposition (MED) method, for deriving principles of transcription regulation at the single-gene resolution level. MED operates on all genes in a genome without requiring any a priori knowledge of gene cluster membership, or manual tuning of parameters. Applying MED to Saccharomyces cerevisiae transcriptional networks, we identified four functions describing four different ways that CREs can quantitatively affect gene expression levels. These functions, three of which have extrema in different positions in the gene promoter (short-, mid-, and long-range) whereas the other depends on the motif orientation, are validated by expression data. We illustrate how nature could use these principles as an additional dimension to amplify the combinatorial power of a small set of CREs in regulating transcription. PMID:16738557

  14. The biological default state of cell proliferation with variation and motility, a fundamental principle for a theory of organisms

    PubMed Central

    SOTO, ANA M.; LONGO, GIUSEPPE; Montévil, Maël; SONNENSCHEIN, CARLOS

    2017-01-01

    The principle of inertia is central to the modern scientific revolution. By postulating this principle Galileo at once identified a pertinent physical observable (momentum) and a conservation law (momentum conservation). He then could scientifically analyze what modifies inertial movement: gravitation and friction. Inertia, the default state in mechanics, represented a major theoretical commitment: there is no need to explain uniform rectilinear motion, rather, there is a need to explain departures from it. By analogy, we propose a biological default state of proliferation with variation and motility. From this theoretical commitment, what requires explanation is proliferative quiescence, lack of variation, lack of movement. That proliferation is the default state is axiomatic for biologists studying unicellular organisms. Moreover, it is implied in Darwin’s “descent with modification”. Although a “default state” is a theoretical construct and a limit case that does not need to be instantiated, conditions that closely resemble unrestrained cell proliferation are readily obtained experimentally. We will illustrate theoretical and experimental consequences of applying and of ignoring this principle. PMID:27381480

  15. Promoting knowledge integration of scientific principles and environmental stewardship: Assessing an issue-based approach to teaching evolution and marine conservation

    NASA Astrophysics Data System (ADS)

    Zimmerman, Timothy David

    2005-11-01

    Students and citizens need to apply science to important issues every day. Yet the design of science curricula that foster integration of science and everyday decisions is not well understood. For example, can curricula be designed that help learners apply scientific reasons for choosing only environmentally sustainable seafood for dinner? Learners must develop integrated understandings of scientific principles, prior experiences, and current decisions in order to comprehend how everyday decisions impact environmental resources. In order to investigate how such integrated understandings can be promoted within school science classes, research was conducted with an inquiry-oriented curriculum that utilizes technology and a visit to an informal learning environment (aquarium) to promote the integration of scientific principles (adaptation) with environmental stewardship. This research used a knowledge integration approach to teaching and learning that provided a framework for promoting the application of science to environmental issues. Marine biology, often forsaken in classrooms for terrestrial biology, served as the scientific context for the curriculum. The curriculum design incorporated a three-phase pedagogical strategy and new technology tools to help students integrate knowledge and experiences across the classroom and aquarium learning environments. The research design and assessment protocols included comparisons among and within student populations using two versions of the curriculum: an issue-based version and a principle-based version. These inquiry curricula were tested with sophomore biology students attending a marine-focused academy within a coastal California high school. Pretest-posttest outcomes were compared between and within the curricular treatments. Additionally, comparisons were made between the inquiry groups and seniors in an Advanced Placement biology course who attend the same high school. Results indicate that the inquiry curricula enabled students to integrate and apply knowledge of evolutionary biology to real-world environmental stewardship issues. Over the course of the curriculum, students' ideas became more scientifically normative and tended to focus around concepts of natural selection. Students using the inquiry curricula outperformed the Advanced Placement biology students on several measures, including knowledge of evolutionary biology. These results have implications for designing science curricula that seek to promote the application of science to environmental stewardship and integrate formal and informal learning environments.

  16. Theory of light transfer in food and biological materials

    USDA-ARS?s Scientific Manuscript database

    In this chapter, we first define the basic radiometric quantities that are needed for describing light propagation in food and biological materials. Radiative transfer theory is then derived, according to the principle of the conservation of energy. Because the radiative transfer theory equation is ...

  17. Learning by stimulation avoidance: A principle to control spiking neural networks dynamics

    PubMed Central

    Sinapayen, Lana; Ikegami, Takashi

    2017-01-01

    Learning based on networks of real neurons, and learning based on biologically inspired models of neural networks, have yet to find general learning rules leading to widespread applications. In this paper, we argue for the existence of a principle allowing to steer the dynamics of a biologically inspired neural network. Using carefully timed external stimulation, the network can be driven towards a desired dynamical state. We term this principle “Learning by Stimulation Avoidance” (LSA). We demonstrate through simulation that the minimal sufficient conditions leading to LSA in artificial networks are also sufficient to reproduce learning results similar to those obtained in biological neurons by Shahaf and Marom, and in addition explains synaptic pruning. We examined the underlying mechanism by simulating a small network of 3 neurons, then scaled it up to a hundred neurons. We show that LSA has a higher explanatory power than existing hypotheses about the response of biological neural networks to external simulation, and can be used as a learning rule for an embodied application: learning of wall avoidance by a simulated robot. In other works, reinforcement learning with spiking networks can be obtained through global reward signals akin simulating the dopamine system; we believe that this is the first project demonstrating sensory-motor learning with random spiking networks through Hebbian learning relying on environmental conditions without a separate reward system. PMID:28158309

  18. Learning by stimulation avoidance: A principle to control spiking neural networks dynamics.

    PubMed

    Sinapayen, Lana; Masumori, Atsushi; Ikegami, Takashi

    2017-01-01

    Learning based on networks of real neurons, and learning based on biologically inspired models of neural networks, have yet to find general learning rules leading to widespread applications. In this paper, we argue for the existence of a principle allowing to steer the dynamics of a biologically inspired neural network. Using carefully timed external stimulation, the network can be driven towards a desired dynamical state. We term this principle "Learning by Stimulation Avoidance" (LSA). We demonstrate through simulation that the minimal sufficient conditions leading to LSA in artificial networks are also sufficient to reproduce learning results similar to those obtained in biological neurons by Shahaf and Marom, and in addition explains synaptic pruning. We examined the underlying mechanism by simulating a small network of 3 neurons, then scaled it up to a hundred neurons. We show that LSA has a higher explanatory power than existing hypotheses about the response of biological neural networks to external simulation, and can be used as a learning rule for an embodied application: learning of wall avoidance by a simulated robot. In other works, reinforcement learning with spiking networks can be obtained through global reward signals akin simulating the dopamine system; we believe that this is the first project demonstrating sensory-motor learning with random spiking networks through Hebbian learning relying on environmental conditions without a separate reward system.

  19. Quantum Information Biology: From Information Interpretation of Quantum Mechanics to Applications in Molecular Biology and Cognitive Psychology

    NASA Astrophysics Data System (ADS)

    Asano, Masanari; Basieva, Irina; Khrennikov, Andrei; Ohya, Masanori; Tanaka, Yoshiharu; Yamato, Ichiro

    2015-10-01

    We discuss foundational issues of quantum information biology (QIB)—one of the most successful applications of the quantum formalism outside of physics. QIB provides a multi-scale model of information processing in bio-systems: from proteins and cells to cognitive and social systems. This theory has to be sharply distinguished from "traditional quantum biophysics". The latter is about quantum bio-physical processes, e.g., in cells or brains. QIB models the dynamics of information states of bio-systems. We argue that the information interpretation of quantum mechanics (its various forms were elaborated by Zeilinger and Brukner, Fuchs and Mermin, and D' Ariano) is the most natural interpretation of QIB. Biologically QIB is based on two principles: (a) adaptivity; (b) openness (bio-systems are fundamentally open). These principles are mathematically represented in the framework of a novel formalism— quantum adaptive dynamics which, in particular, contains the standard theory of open quantum systems.

  20. On extracting design principles from biology: I. Method-General answers to high-level design questions for bioinspired robots.

    PubMed

    Haberland, M; Kim, S

    2015-02-02

    When millions of years of evolution suggest a particular design solution, we may be tempted to abandon traditional design methods and copy the biological example. However, biological solutions do not often translate directly into the engineering domain, and even when they do, copying eliminates the opportunity to improve. A better approach is to extract design principles relevant to the task of interest, incorporate them in engineering designs, and vet these candidates against others. This paper presents the first general framework for determining whether biologically inspired relationships between design input variables and output objectives and constraints are applicable to a variety of engineering systems. Using optimization and statistics to generalize the results beyond a particular system, the framework overcomes shortcomings observed of ad hoc methods, particularly those used in the challenging study of legged locomotion. The utility of the framework is demonstrated in a case study of the relative running efficiency of rotary-kneed and telescoping-legged robots.

  1. Data management and data enrichment for systems biology projects.

    PubMed

    Wittig, Ulrike; Rey, Maja; Weidemann, Andreas; Müller, Wolfgang

    2017-11-10

    Collecting, curating, interlinking, and sharing high quality data are central to de.NBI-SysBio, the systems biology data management service center within the de.NBI network (German Network for Bioinformatics Infrastructure). The work of the center is guided by the FAIR principles for scientific data management and stewardship. FAIR stands for the four foundational principles Findability, Accessibility, Interoperability, and Reusability which were established to enhance the ability of machines to automatically find, access, exchange and use data. Within this overview paper we describe three tools (SABIO-RK, Excemplify, SEEK) that exemplify the contribution of de.NBI-SysBio services to FAIR data, models, and experimental methods storage and exchange. The interconnectivity of the tools and the data workflow within systems biology projects will be explained. For many years we are the German partner in the FAIRDOM initiative (http://fair-dom.org) to establish a European data and model management service facility for systems biology. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  2. New Potential Pharmaceutical Applications of Hypericum Species.

    PubMed

    Marrelli, Mariangela; Statti, Giancarlo; Conforti, Filomena; Menichini, Francesco

    2016-01-01

    The genus Hypericum includes more than 450 species distributed in Europe, North America, North Africa and West Asia. These plants are widely used in folk medicine for the treatment of inflammation, bacterial and viral infections, burns and gastric disorders. The use for alleviating inflammation and promoting wound healing is well known for H. Perforatum L. (St. John's wort) and other species. Because of its pharmacological activity, H. perforatum L. is one of the most important species of this genus. This plant has been largely utilized for its efficacy in the treatment of mild to moderate depression. However, some other species have been utilized in traditional medicine and have been studied for their phytochemical composition and for their biological activities to date. Hypericum species contain biologically active secondary metabolites belonging to at least ten different classes, with prevalence of naphthodianthrones (hypericin and pseudohypericin), phloroglucinols (hyperforin), flavonoids (rutin, hyperoside, isoquercitrin, quercitrin, quercetin, amentoflavone) and phenylpropanoids (chlorogenic acid). However, great variations in contents have been reported for wild populations worldwide. The purpose of this review is to provide an overview of most recent studies about potential pharmaceutical applications of plants belonging to Hypericum genus. The most interesting isolated active principles and both in vitro and in vivo effects of Hypericum extracts are presented and discussed.

  3. Phytochemical and biological evaluation of some Sargassum species from Persian Gulf

    PubMed Central

    Mehdinezhad, Negin; Ghannadi, Alireza; Yegdaneh, Afsaneh

    2016-01-01

    Sea algae are widely consumed in the world. There are several seaweeds including brown algae which are authorized for human consumption. These plants contain important phytochemical constituents and have various potential biological activities. The present study investigated the presence of phytochemical constituents and total phenolic quantity of the seaweeds Sargassum angustifolium, Sargassum oligocystum and Sargassum boveanum. Cytotoxicity of seaweeds was tested against HT-29, HeLa and MCF-7 cell lines. Antioxidant potential of these 3 Sargassum species was also analyzed. Cytotoxicity was characterized by IC50 of human cancer cell lines using sulforhodamine assay. Antioxidant activities were evaluated using 2,2-diphenyl-1- picrylhydrazil. The analysis revealed that tannins, saponins, sterols and triterpenes were the most abundant compounds in these Sargassum species while cyanogenic and cardiac glycosides were the least ones. Sargassum angustifolium had the highest content of total phenolics (0.061 mg/g) and showed the highest antioxidant activity (IC50 = 0.231). Cytotoxic results showed that all species could inhibit cell growth effectively, especially MCF-7 cell line (IC50 = 67.3, 56.9, 60.4 for S. oligocystum, S. angustifolium and S. boveanum respectively). Considerable phytochemicals and moderate cytotoxic activity of S. angustifolium, S. oligocystum and S. boveanum make them appropriate candidate for further studies and identification of their bioactive principles. PMID:27499794

  4. Phytochemical and biological evaluation of some Sargassum species from Persian Gulf.

    PubMed

    Mehdinezhad, Negin; Ghannadi, Alireza; Yegdaneh, Afsaneh

    2016-01-01

    Sea algae are widely consumed in the world. There are several seaweeds including brown algae which are authorized for human consumption. These plants contain important phytochemical constituents and have various potential biological activities. The present study investigated the presence of phytochemical constituents and total phenolic quantity of the seaweeds Sargassum angustifolium, Sargassum oligocystum and Sargassum boveanum. Cytotoxicity of seaweeds was tested against HT-29, HeLa and MCF-7 cell lines. Antioxidant potential of these 3 Sargassum species was also analyzed. Cytotoxicity was characterized by IC50 of human cancer cell lines using sulforhodamine assay. Antioxidant activities were evaluated using 2,2-diphenyl-1- picrylhydrazil. The analysis revealed that tannins, saponins, sterols and triterpenes were the most abundant compounds in these Sargassum species while cyanogenic and cardiac glycosides were the least ones. Sargassum angustifolium had the highest content of total phenolics (0.061 mg/g) and showed the highest antioxidant activity (IC50 = 0.231). Cytotoxic results showed that all species could inhibit cell growth effectively, especially MCF-7 cell line (IC50 = 67.3, 56.9, 60.4 for S. oligocystum, S. angustifolium and S. boveanum respectively). Considerable phytochemicals and moderate cytotoxic activity of S. angustifolium, S. oligocystum and S. boveanum make them appropriate candidate for further studies and identification of their bioactive principles.

  5. In search of principles for a Theory of Organisms

    PubMed Central

    Longo, Giuseppe; Montévil, Maël; Sonnenschein, Carlos; Soto, Ana M

    2017-01-01

    Lacking an operational theory to explain the organization and behaviour of matter in unicellular and multicellular organisms hinders progress in biology. Such a theory should address life cycles from ontogenesis to death. This theory would complement the theory of evolution that addresses phylogenesis, and would posit theoretical extensions to accepted physical principles and default states in order to grasp the living state of matter and define proper biological observables. Thus, we favour adopting the default state implicit in Darwin’s theory, namely, cell proliferation with variation plus motility, and a framing principle, namely, life phenomena manifest themselves as non-identical iterations of morphogenetic processes. From this perspective, organisms become a consequence of the inherent variability generated by proliferation, motility and self-organization. Morphogenesis would then be the result of the default state plus physical constraints, like gravity, and those present in living organisms, like muscular tension. PMID:26648040

  6. WormClassroom.org: An Inquiry-rich Educational Web Portal for Research Resources of Caenorhabditis elegans

    PubMed Central

    Lu, Fong-Mei; Stewart, James; White, John G.

    2007-01-01

    The utilization of biology research resources, coupled with a “learning by inquiry” approach, has great potential to aid students in gaining an understanding of fundamental biological principles. To help realize this potential, we have developed a Web portal for undergraduate biology education, WormClassroom.org, based on current research resources of a model research organism, Caenorhabditis elegans. This portal is intended to serve as a resource gateway for students to learn biological concepts using C. elegans research material. The driving forces behind the WormClassroom website were the strengths of C. elegans as a teaching organism, getting researchers and educators to work together to develop instructional materials, and the 3 P's (problem posing, problem solving, and peer persuasion) approach for inquiry learning. Iterative assessment is an important aspect of the WormClassroom site development because it not only ensures that content is up-to-date and accurate, but also verifies that it does, in fact, aid student learning. A primary assessment was performed to refine the WormClassroom website utilizing undergraduate biology students and nonstudent experts such as C. elegans researchers; results and comments were used for site improvement. We are actively encouraging continued resource contributions from the C. elegans research and education community for the further development of WormClassroom. PMID:17548872

  7. Multidisciplinary Russian biomedical research in space

    NASA Astrophysics Data System (ADS)

    Orlov, O. I.; Sychev, V. N.; Samarin, G. I.; Ilyin, E. A.; Belakovskiy, M. S.; Kussmaul, A. R.

    2014-08-01

    Research activities on a comprehensive multidisciplinary program are vital for enhancement of the system of crew's medical care, environmental health and hygiene in space missions. The primary goal of the program must be identification of patterns, intensity and dynamics of structural and functional shifts in organism induced by an aggregate of spaceflight factors including microgravity, isolation, artificial environment, space radiation, etc. Also, the program must pursue differential assessment of emerging deviations from the standpoint of adequacy to the spaceflight conditions and prospects of returning to Earth and guide the development of principles, methods and techniques necessary to maintain health and working capacity of humans during short- and long-duration missions and on return to Earth. Over 50 years, since 1963, the IBMP researchers apply systemic and innovational approaches to fundamental and exploratory studies in the fields of medical sciences, radiation biology, engineering science, biotechnology, etc. with participation of various biological specimens and human volunteers. Investigations aboard manned spacecrafts and biological satellites as well as in ground-based laboratories further enhancement of the medical care system for crews on orbital and remote space missions; they give insight into the fundamental problems of gravitational physiology and biology, psychophysiology, radiation biology, and contribute thereby to the development of knowledge, methods and technologies, as well as medical and scientific equipment.

  8. The biological microprocessor, or how to build a computer with biological parts

    PubMed Central

    Moe-Behrens, Gerd HG

    2013-01-01

    Systemics, a revolutionary paradigm shift in scientific thinking, with applications in systems biology, and synthetic biology, have led to the idea of using silicon computers and their engineering principles as a blueprint for the engineering of a similar machine made from biological parts. Here we describe these building blocks and how they can be assembled to a general purpose computer system, a biological microprocessor. Such a system consists of biological parts building an input / output device, an arithmetic logic unit, a control unit, memory, and wires (busses) to interconnect these components. A biocomputer can be used to monitor and control a biological system. PMID:24688733

  9. Microfluidic chips with multi-junctions: an advanced tool in recovering proteins from inclusion bodies

    PubMed Central

    Yamaguchi, Hiroshi; Miyazaki, Masaya

    2015-01-01

    Active recombinant proteins are used for studying the biological functions of genes and for the development of therapeutic drugs. Overexpression of recombinant proteins in bacteria often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. Protein refolding is an important process for obtaining active recombinant proteins from inclusion bodies. However, the conventional refolding method of dialysis or dilution is time-consuming and recovered active protein yields are often low, and a cumbersome trial-and-error process is required to achieve success. To circumvent these difficulties, we used controllable diffusion through laminar flow in microchannels to regulate the denaturant concentration. This method largely aims at reducing protein aggregation during the refolding procedure. This Commentary introduces the principles of the protein refolding method using microfluidic chips and the advantage of our results as a tool for rapid and efficient recovery of active recombinant proteins from inclusion bodies. PMID:25531187

  10. Microfluidic chips with multi-junctions: an advanced tool in recovering proteins from inclusion bodies.

    PubMed

    Yamaguchi, Hiroshi; Miyazaki, Masaya

    2015-01-01

    Active recombinant proteins are used for studying the biological functions of genes and for the development of therapeutic drugs. Overexpression of recombinant proteins in bacteria often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. Protein refolding is an important process for obtaining active recombinant proteins from inclusion bodies. However, the conventional refolding method of dialysis or dilution is time-consuming and recovered active protein yields are often low, and a cumbersome trial-and-error process is required to achieve success. To circumvent these difficulties, we used controllable diffusion through laminar flow in microchannels to regulate the denaturant concentration. This method largely aims at reducing protein aggregation during the refolding procedure. This Commentary introduces the principles of the protein refolding method using microfluidic chips and the advantage of our results as a tool for rapid and efficient recovery of active recombinant proteins from inclusion bodies.

  11. The foundations of space biology and medicine. Volume 2: Ecological and physiological bases of space biology and medicine. Part 3: Effect on the organism of dynamic flight factors. Chapter 1: Principles of gravitational biology

    NASA Technical Reports Server (NTRS)

    Smith, A. H.

    1972-01-01

    The physical principles of gravitation are discussed, such as gravitational and intertial forces, weight and mass, weightlessness, size and scale effects, scale limits of gravitational effects, and gravity as a biogenic factor. The behavior of the accelerative force gravitation, is described. This law proposes and quantifies the mutual gravitational attraction existing between all bodies of matter, the force being proportional to the product of masses, and inversely related to the square of the distance separating them. Gravity orientation, chronic acceleration, and hematology are examined. Systematic responses, such as circulation and renal functions, are also considered, along with animal response to a decreased acceleration field and physiology of hyper- and hypodynamic fields.

  12. Colloquium: Modeling the dynamics of multicellular systems: Application to tissue engineering

    NASA Astrophysics Data System (ADS)

    Kosztin, Ioan; Vunjak-Novakovic, Gordana; Forgacs, Gabor

    2012-10-01

    Tissue engineering is a rapidly evolving discipline that aims at building functional tissues to improve or replace damaged ones. To be successful in such an endeavor, ideally, the engineering of tissues should be based on the principles of developmental biology. Recent progress in developmental biology suggests that the formation of tissues from the composing cells is often guided by physical laws. Here a comprehensive computational-theoretical formalism is presented that is based on experimental input and incorporates biomechanical principles of developmental biology. The formalism is described and it is shown that it correctly reproduces and predicts the quantitative characteristics of the fundamental early developmental process of tissue fusion. Based on this finding, the formalism is then used toward the optimization of the fabrication of tubular multicellular constructs, such as a vascular graft, by bioprinting, a novel tissue engineering technology.

  13. Critique of pure free energy principle. Comment on "Answering Schrödinger's question: A free-energy formulation" by Maxwell James Désormeau Ramstead et al.

    NASA Astrophysics Data System (ADS)

    Tozzi, Arturo; Peters, James F.

    2018-03-01

    The paper by Ramstead et al. [1] [in this issue] reminds us the efforts of eminent scientists such as Whitehead and Godel. After having produced influential manuscripts, they turned to more philosophical issues, understanding the need for a larger formalization of their bounteous scientific results [2,3]. In a similar way, the successful free-energy principle has been generalized, in order to encompass not only the brain activity of the original formulation, but also the whole spectrum of life [1]. The final result is of prominent importance, because, in touch with Quine's naturalized epistemology [4] and Badiou's account of set theory [5], provides philosophical significance to otherwise purely scientific matters. The free energy principle becomes a novel paradigm that attempts to explain general physical/biological mechanisms in the light of a novel scientific ontology, the "variational neuroethology". The latter, seemingly grounded in a recursive multilevel reductionistic/emergentistic approach à la Bechtel [6], has also its roots in a rationalistic top-down approach that, starting from mathematical/physical general concepts (von Helmholtz's free energy), formulates experimentally testable (and falsifiable) theories.

  14. Principles of Safety Pharmacology

    PubMed Central

    Pugsley, M K; Authier, S; Curtis, M J

    2008-01-01

    Safety Pharmacology is a rapidly developing discipline that uses the basic principles of pharmacology in a regulatory-driven process to generate data to inform risk/benefit assessment. The aim of Safety Pharmacology is to characterize the pharmacodynamic/pharmacokinetic (PK/PD) relationship of a drug's adverse effects using continuously evolving methodology. Unlike toxicology, Safety Pharmacology includes within its remit a regulatory requirement to predict the risk of rare lethal events. This gives Safety Pharmacology its unique character. The key issues for Safety Pharmacology are detection of an adverse effect liability, projection of the data into safety margin calculation and finally clinical safety monitoring. This article sets out to explain the drivers for Safety Pharmacology so that the wider pharmacology community is better placed to understand the discipline. It concludes with a summary of principles that may help inform future resolution of unmet needs (especially establishing model validation for accurate risk assessment). Subsequent articles in this issue of the journal address specific aspects of Safety Pharmacology to explore the issues of model choice, the burden of proof and to highlight areas of intensive activity (such as testing for drug-induced rare event liability, and the challenge of testing the safety of so-called biologics (antibodies, gene therapy and so on.). PMID:18604233

  15. Emerging principles of regulatory evolution.

    PubMed

    Prud'homme, Benjamin; Gompel, Nicolas; Carroll, Sean B

    2007-05-15

    Understanding the genetic and molecular mechanisms governing the evolution of morphology is a major challenge in biology. Because most animals share a conserved repertoire of body-building and -patterning genes, morphological diversity appears to evolve primarily through changes in the deployment of these genes during development. The complex expression patterns of developmentally regulated genes are typically controlled by numerous independent cis-regulatory elements (CREs). It has been proposed that morphological evolution relies predominantly on changes in the architecture of gene regulatory networks and in particular on functional changes within CREs. Here, we discuss recent experimental studies that support this hypothesis and reveal some unanticipated features of how regulatory evolution occurs. From this growing body of evidence, we identify three key operating principles underlying regulatory evolution, that is, how regulatory evolution: (i) uses available genetic components in the form of preexisting and active transcription factors and CREs to generate novelty; (ii) minimizes the penalty to overall fitness by introducing discrete changes in gene expression; and (iii) allows interactions to arise among any transcription factor and downstream CRE. These principles endow regulatory evolution with a vast creative potential that accounts for both relatively modest morphological differences among closely related species and more profound anatomical divergences among groups at higher taxonomical levels.

  16. "Life-bearing molecules" versus "life-embodying systems": Two contrasting views on the what-is-life (WIL) problem persisting from the early days of molecular biology to the post-genomic cell- and organism-level biology.

    PubMed

    Sato, Naoki

    2018-05-01

    "What is life?" is an ultimate biological quest for the principle that makes organisms alive. This 'WIL problem' is not, however, a simple one that we have a straightforward strategy to attack. From the beginning, molecular biology tried to identify molecules that bear the essence of life: the double helical DNA represented replication, and enzymes were micro-actuators of biological activities. A dominating idea behind these mainstream biological studies relies on the identification of life-bearing molecules, which themselves are models of life. Another, prevalent idea emphasizes that life resides in the whole system of an organism, but not in some particular molecules. The behavior of a complex system may be considered to embody the essence of life. The thermodynamic view of life system in the early 20th century was remodeled as physics of complex systems and systems biology. The two views contrast with each other, but they are no longer heritage of the historical dualism in biology, such as mechanism/materialism versus vitalism, or reductionism versus holism. These two views are both materialistic and mechanistic, and act as driving forces of modern biology. In reality, molecules function in a context of systems, whereas systems presuppose functional molecules. A key notion to reconcile this conflict is that subjects of biological studies are given before we start to study them. Cell- or organism-level biology is destined to the dialectic of molecules and systems, but this antagonism can be resolved by dynamic thinking involving biological evolution. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Vas deferens neuro-effector junction: from kymographic tracings to structural biology principles.

    PubMed

    Navarrete, L Camilo; Barrera, Nelson P; Huidobro-Toro, J Pablo

    2014-10-01

    The vas deferens is a simple bioassay widely used to study the physiology of sympathetic neurotransmission and the pharmacodynamics of adrenergic drugs. The role of ATP as a sympathetic co-transmitter has gained increasing attention and furthered our understanding of its role in sympathetic reflexes. In addition, new information has emerged on the mechanisms underlying the storage and release of ATP. Both noradrenaline and ATP concur to elicit the tissue smooth muscle contractions following sympathetic reflexes or electrical field stimulation of the sympathetic nerve terminals. ATP and adenosine (its metabolic byproduct) are powerful presynaptic regulators of co-transmitter actions. In addition, neuropeptide Y, the third member of the sympathetic triad, is an endogenous modulator. The peptide plus ATP and/or adenosine play a significant role as sympathetic modulators of transmitter's release. This review focuses on the physiological principles that govern sympathetic co-transmitter activity, with special interest in defining the motor role of ATP. In addition, we intended to review the recent structural biology findings related to the topology of the P2X1R based on the crystallized P2X4 receptor from Danio rerio, or the crystallized adenosine A2A receptor as a member of the G protein coupled family of receptors as prototype neuro modulators. This review also covers structural elements of ectonucleotidases, since some members are found in the vas deferens neuro-effector junction. The allosteric principles that apply to purinoceptors are also reviewed highlighting concepts derived from receptor theory at the light of the current available structural elements. Finally, we discuss clinical applications of these concepts. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. How protein materials balance strength, robustness, and adaptability

    PubMed Central

    Buehler, Markus J.; Yung, Yu Ching

    2010-01-01

    Proteins form the basis of a wide range of biological materials such as hair, skin, bone, spider silk, or cells, which play an important role in providing key functions to biological systems. The focus of this article is to discuss how protein materials are capable of balancing multiple, seemingly incompatible properties such as strength, robustness, and adaptability. To illustrate this, we review bottom-up materiomics studies focused on the mechanical behavior of protein materials at multiple scales, from nano to macro. We focus on alpha-helix based intermediate filament proteins as a model system to explain why the utilization of hierarchical structural features is vital to their ability to combine strength, robustness, and adaptability. Experimental studies demonstrating the activation of angiogenesis, the growth of new blood vessels, are presented as an example of how adaptability of structure in biological tissue is achieved through changes in gene expression that result in an altered material structure. We analyze the concepts in light of the universality and diversity of the structural makeup of protein materials and discuss the findings in the context of potential fundamental evolutionary principles that control their nanoscale structure. We conclude with a discussion of multiscale science in biology and de novo materials design. PMID:20676305

  19. Global Consensus Theorem and Self-Organized Criticality: Unifying Principles for Understanding Self-Organization, Swarm Intelligence and Mechanisms of Carcinogenesis

    PubMed Central

    Rosenfeld, Simon

    2013-01-01

    Complex biological systems manifest a large variety of emergent phenomena among which prominent roles belong to self-organization and swarm intelligence. Generally, each level in a biological hierarchy possesses its own systemic properties and requires its own way of observation, conceptualization, and modeling. In this work, an attempt is made to outline general guiding principles in exploration of a wide range of seemingly dissimilar phenomena observed in large communities of individuals devoid of any personal intelligence and interacting with each other through simple stimulus-response rules. Mathematically, these guiding principles are well captured by the Global Consensus Theorem (GCT) equally applicable to neural networks and to Lotka-Volterra population dynamics. Universality of the mechanistic principles outlined by GCT allows for a unified approach to such diverse systems as biological networks, communities of social insects, robotic communities, microbial communities, communities of somatic cells, social networks and many other systems. Another cluster of universal laws governing the self-organization in large communities of locally interacting individuals is built around the principle of self-organized criticality (SOC). The GCT and SOC, separately or in combination, provide a conceptual basis for understanding the phenomena of self-organization occurring in large communities without involvement of a supervisory authority, without system-wide informational infrastructure, and without mapping of general plan of action onto cognitive/behavioral faculties of its individual members. Cancer onset and proliferation serves as an important example of application of these conceptual approaches. In this paper, the point of view is put forward that apparently irreconcilable contradictions between two opposing theories of carcinogenesis, that is, the Somatic Mutation Theory and the Tissue Organization Field Theory, may be resolved using the systemic approaches provided by GST and SOC. PMID:23471309

  20. Xenohormesis: health benefits from an eon of plant stress response evolution

    PubMed Central

    Hooper, Paul L.; Tytell, Michael; Vígh, Lászlo

    2010-01-01

    Xenohormesis is a biological principle that explains how environmentally stressed plants produce bioactive compounds that can confer stress resistance and survival benefits to animals that consume them. Animals can piggyback off products of plants' sophisticated stress response which has evolved as a result of their stationary lifestyle. Factors eliciting the plant stress response can judiciously be employed to maximize yield of health-promoting plant compounds. The xenohormetic plant compounds can, when ingested, improve longevity and fitness by activating the animal's cellular stress response and can be applied in drug discovery, drug production, and nutritional enhancement of diet. PMID:20524162

  1. Lectins of beneficial microbes: system organisation, functioning and functional superfamily.

    PubMed

    Lakhtin, M; Lakhtin, V; Alyoshkin, V; Afanasyev, S

    2011-06-01

    In this review our last results and proposals with respect to general aspects of lectin studies are summarised and compared. System presence, organisation and functioning of lectins are proposed, and accents on beneficial symbiotic microbial lectins studies are presented. The proposed general principles of lectin functioning allows for a comparison of lectins with other carbohydrate-recognition systems. A new structure-functional superfamily of symbiotic microbial lectins is proposed and its main properties are described. The proposed superfamily allows for extended searches of the biological activities of any microbial member. Prospects of lectins of beneficial symbiotic microorganisms are discussed.

  2. 3D Diffraction Microscope Provides a First Deep View

    NASA Astrophysics Data System (ADS)

    Miao, Jianwei

    2005-03-01

    When a coherent diffraction pattern is sampled at a spacing sufficiently finer than the Bragg peak frequency (i.e. the inverse of the sample size), the phase information is in principle encoded inside the diffraction pattern, and can be directly retrieved by using an iterative process. In combination of this oversampling phasing method with either coherent X-rays or electrons, a novel form of diffraction microscopy has recently been developed to image nanoscale materials and biological structures. In this talk, I will present the principle of the oversampling method, discuss the first experimental demonstration of this microscope, and illustrate some applications in nanoscience and biology.

  3. Thiol/disulfide redox states in signaling and sensing

    PubMed Central

    Go, Young-Mi; Jones, Dean P.

    2015-01-01

    Rapid advances in redox systems biology are creating new opportunities to understand complexities of human disease and contributions of environmental exposures. New understanding of thiol-disulfide systems have occurred during the past decade as a consequence of the discoveries that thiol and disulfide systems are maintained in kinetically controlled steady-states displaced from thermodynamic equilibrium, that a widely distributed family of NADPH oxidases produces oxidants that function in cell signaling, and that a family of peroxiredoxins utilize thioredoxin as a reductant to complement the well-studied glutathione antioxidant system for peroxide elimination and redox regulation. This review focuses on thiol/disulfide redox state in biologic systems and the knowledge base available to support development of integrated redox systems biology models to better understand the function and dysfunction of thiol-disulfide redox systems. In particular, central principles have emerged concerning redox compartmentalization and utility of thiol/disulfide redox measures as indicators of physiologic function. Advances in redox proteomics show that, in addition to functioning in protein active sites and cell signaling, cysteine residues also serve as redox sensors to integrate biologic functions. These advances provide a framework for translation of redox systems biology concepts to practical use in understanding and treating human disease. Biological responses to cadmium, a widespread environmental agent, are used to illustrate the utility of these advances to the understanding of complex pleiotropic toxicities. PMID:23356510

  4. Biologically-based signal processing system applied to noise removal for signal extraction

    DOEpatents

    Fu, Chi Yung; Petrich, Loren I.

    2004-07-13

    The method and system described herein use a biologically-based signal processing system for noise removal for signal extraction. A wavelet transform may be used in conjunction with a neural network to imitate a biological system. The neural network may be trained using ideal data derived from physical principles or noiseless signals to determine to remove noise from the signal.

  5. Sensing the Coherence of Biology in Contrast to Psychology: Young Children's Use of Causal Relations to Distinguish Two Foundational Domains

    ERIC Educational Resources Information Center

    Erickson, Jane E.; Keil, Frank C.; Lockhart, Kristi L.

    2010-01-01

    To what extent do children understand that biological processes fall into 1 coherent domain unified by distinct causal principles? In Experiments 1 and 2 (N = 125) kindergartners are given triads of biological and psychological processes and asked to identify which 2 members of the triad belong together. Results show that 5-year-olds correctly…

  6. El control biologico de plagas(Biological control of pests)

    USDA-ARS?s Scientific Manuscript database

    In this work some ecological principles that drive applied biocontrol and agent selection are discussed. Subjects such as specificity evaluations, host shifts and species invasiveness are analyzed under the light of ecological theory. The main assertions are: 1. biological control is a safe and bene...

  7. Teaching Molecular Biology with Microcomputers.

    ERIC Educational Resources Information Center

    Reiss, Rebecca; Jameson, David

    1984-01-01

    Describes a series of computer programs that use simulation and gaming techniques to present the basic principles of the central dogma of molecular genetics, mutation, and the genetic code. A history of discoveries in molecular biology is presented and the evolution of these computer assisted instructional programs is described. (MBR)

  8. Parts plus pipes: synthetic biology approaches to metabolic engineering

    PubMed Central

    Boyle, Patrick M.; Silver, Pamela A.

    2011-01-01

    Synthetic biologists combine modular biological “parts” to create higher-order devices. Metabolic engineers construct biological “pipes” by optimizing the microbial conversion of basic substrates to desired compounds. Many scientists work at the intersection of these two philosophies, employing synthetic devices to enhance metabolic engineering efforts. These integrated approaches promise to do more than simply improve product yields; they can expand the array of products that are tractable to produce biologically. In this review, we explore the application of synthetic biology techniques to next-generation metabolic engineering challenges, as well as the emerging engineering principles for biological design. PMID:22037345

  9. Systematic variation in the temperature dependence of physiological and ecological traits.

    PubMed

    Dell, Anthony I; Pawar, Samraat; Savage, Van M

    2011-06-28

    To understand the effects of temperature on biological systems, we compile, organize, and analyze a database of 1,072 thermal responses for microbes, plants, and animals. The unprecedented diversity of traits (n = 112), species (n = 309), body sizes (15 orders of magnitude), and habitats (all major biomes) in our database allows us to quantify novel features of the temperature response of biological traits. In particular, analysis of the rising component of within-species (intraspecific) responses reveals that 87% are fit well by the Boltzmann-Arrhenius model. The mean activation energy for these rises is 0.66 ± 0.05 eV, similar to the reported across-species (interspecific) value of 0.65 eV. However, systematic variation in the distribution of rise activation energies is evident, including previously unrecognized right skewness around a median of 0.55 eV. This skewness exists across levels of organization, taxa, trophic groups, and habitats, and it is partially explained by prey having increased trait performance at lower temperatures relative to predators, suggesting a thermal version of the life-dinner principle-stronger selection on running for your life than running for your dinner. For unimodal responses, habitat (marine, freshwater, and terrestrial) largely explains the mean temperature at which trait values are optimal but not variation around the mean. The distribution of activation energies for trait falls has a mean of 1.15 ± 0.39 eV (significantly higher than rises) and is also right-skewed. Our results highlight generalities and deviations in the thermal response of biological traits and help to provide a basis to predict better how biological systems, from cells to communities, respond to temperature change.

  10. Monitoring and quantifying the passive transport of molecules through patch-clamp suspended real and model cell membranes.

    PubMed

    Messina, Pierluca; Lemaître, Frédéric; Huet, François; Ngo, Kieu An; Vivier, Vincent; Labbé, Eric; Buriez, Olivier; Amatore, Christian

    2014-03-17

    Transport of active molecules across biological membranes is a central issue for the success of many pharmaceutical strategies. Herein, we combine the patch-clamp principle with amperometric detection for monitoring fluxes of redox-tagged molecular species across a suspended membrane patched from a macrophage. Solvent- and protein-free lipid bilayers (DPhPC, DOPC, DOPG) patched from single-wall GUV have been thoroughly investigated and the corresponding fluxes measurements quantified. The quality of the patches and their proper sealing were successfully characterized by electrochemical impedance spectroscopy. This procedure appears versatile and perfectly adequate to allow the investigation of transport and quantification of the transport properties through direct measurement of the coefficients of partition and diffusion of the compound in the membrane, thus offering insight on such important biological and pharmacological issues. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. A Synthetic Biology Framework for Programming Eukaryotic Transcription Functions

    PubMed Central

    Khalil, Ahmad S.; Lu, Timothy K.; Bashor, Caleb J.; Ramirez, Cherie L.; Pyenson, Nora C.; Joung, J. Keith; Collins, James J.

    2013-01-01

    SUMMARY Eukaryotic transcription factors (TFs) perform complex and combinatorial functions within transcriptional networks. Here, we present a synthetic framework for systematically constructing eukaryotic transcription functions using artificial zinc fingers, modular DNA-binding domains found within many eukaryotic TFs. Utilizing this platform, we construct a library of orthogonal synthetic transcription factors (sTFs) and use these to wire synthetic transcriptional circuits in yeast. We engineer complex functions, such as tunable output strength and transcriptional cooperativity, by rationally adjusting a decomposed set of key component properties, e.g., DNA specificity, affinity, promoter design, protein-protein interactions. We show that subtle perturbations to these properties can transform an individual sTF between distinct roles (activator, cooperative factor, inhibitory factor) within a transcriptional complex, thus drastically altering the signal processing behavior of multi-input systems. This platform provides new genetic components for synthetic biology and enables bottom-up approaches to understanding the design principles of eukaryotic transcriptional complexes and networks. PMID:22863014

  12. Integrating population genetics and conservation biology in the era of genomics.

    PubMed

    Ouborg, N Joop

    2010-02-23

    As one of the final activities of the ESF-CONGEN Networking programme, a conference entitled 'Integrating Population Genetics and Conservation Biology' was held at Trondheim, Norway, from 23 to 26 May 2009. Conference speakers and poster presenters gave a display of the state-of-the-art developments in the field of conservation genetics. Over the five-year running period of the successful ESF-CONGEN Networking programme, much progress has been made in theoretical approaches, basic research on inbreeding depression and other genetic processes associated with habitat fragmentation and conservation issues, and with applying principles of conservation genetics in the conservation of many species. Future perspectives were also discussed in the conference, and it was concluded that conservation genetics is evolving into conservation genomics, while at the same time basic and applied research on threatened species and populations from a population genetic point of view continues to be emphasized.

  13. Multimodal magnetic nano-carriers for cancer treatment: Challenges and advancements

    NASA Astrophysics Data System (ADS)

    Aadinath, W.; Ghosh, Triroopa; Anandharamakrishnan, C.

    2016-03-01

    Iron oxide nanoparticles (IONPs) have been a propitious topic for cancer treatment in recent years because of its multifunctional theranostic applications under magnetic field. Two such widely used applications in cancer biology are gradient magnetic field guided targeting and alternative magnetic field (AMF) induced local hyperthermia. Gradient magnetic field guided targeting is a mode of active targeting of therapeutics conjugated with iron oxide nanoparticles. These particles also dissipate heat in presence of AMF which causes thermal injury to the cells of interest, for example tumour cells and subsequent death. Clinical trials divulge the feasibility of such magnetic nano-carrier as a promising candidate in cancer biology. However, these techniques need further investigations to curtail certain limitations manifested. Recent progresses in response have shrunken the barricade to certain extent. In this context, principles, challenges associated with these applications and recent efforts made in response will be discussed.

  14. Selection on Network Dynamics Drives Differential Rates of Protein Domain Evolution

    PubMed Central

    Mannakee, Brian K.; Gutenkunst, Ryan N.

    2016-01-01

    The long-held principle that functionally important proteins evolve slowly has recently been challenged by studies in mice and yeast showing that the severity of a protein knockout only weakly predicts that protein’s rate of evolution. However, the relevance of these studies to evolutionary changes within proteins is unknown, because amino acid substitutions, unlike knockouts, often only slightly perturb protein activity. To quantify the phenotypic effect of small biochemical perturbations, we developed an approach to use computational systems biology models to measure the influence of individual reaction rate constants on network dynamics. We show that this dynamical influence is predictive of protein domain evolutionary rate within networks in vertebrates and yeast, even after controlling for expression level and breadth, network topology, and knockout effect. Thus, our results not only demonstrate the importance of protein domain function in determining evolutionary rate, but also the power of systems biology modeling to uncover unanticipated evolutionary forces. PMID:27380265

  15. Energy coding in biological neural networks

    PubMed Central

    Zhang, Zhikang

    2007-01-01

    According to the experimental result of signal transmission and neuronal energetic demands being tightly coupled to information coding in the cerebral cortex, we present a brand new scientific theory that offers an unique mechanism for brain information processing. We demonstrate that the neural coding produced by the activity of the brain is well described by our theory of energy coding. Due to the energy coding model’s ability to reveal mechanisms of brain information processing based upon known biophysical properties, we can not only reproduce various experimental results of neuro-electrophysiology, but also quantitatively explain the recent experimental results from neuroscientists at Yale University by means of the principle of energy coding. Due to the theory of energy coding to bridge the gap between functional connections within a biological neural network and energetic consumption, we estimate that the theory has very important consequences for quantitative research of cognitive function. PMID:19003513

  16. 76 FR 27062 - Biologics Price Competition and Innovation Act of 2009; Options for a User Fee Program for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... under the Public Health Service Act (PHS Act). FDA is requesting input on the identified principles for... adhere to these principles, and performance goals for this program. FDA plans to review the comments... drug marketing applications were submitted each year for FDA review. The number of participants in the...

  17. [Acoustic detection of absorption of millimeter-band electromagnetic waves in biological objects].

    PubMed

    Polnikov, I G; Putvinskiĭ, A V

    1988-01-01

    Principles of photoacoustic spectroscopy were applied to elaborate a new method for controlling millimeter electromagnetic waves absorption in biological objects. The method was used in investigations of frequency dependence of millimeter wave power absorption in vitro and in vivo in the commonly used experimental irradiation systems.

  18. Interdisciplinarity and Education: Towards Principles of Pedagogical Practice

    ERIC Educational Resources Information Center

    Mulder, Martin

    2012-01-01

    Disciplines play a major role in agricultural education and extension. Biology, chemistry and physics are all essential to understand nature and to improve the quality of agricultural production. During the past centuries, disciplines have evolved, and a multitude of specialisations emerged, like cell biology, colloid chemistry and geophysics. The…

  19. Teaching the Ethics of Biology.

    ERIC Educational Resources Information Center

    Johansen, Carol K.; Harris, David E.

    2000-01-01

    Points out the challenges of educating students about bioethics and the limited training of many biologists on ethics. Discusses the basic principles of ethics and ethical decision making as applied to biology. Explains the models of ethical decision making that are often difficult for students to determine where to begin analyzing. (Contains 28…

  20. Biology 20-30: Program of Studies.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Curriculum Branch.

    Presented in English and French, Biology 20-30 is an academic program that helps students in Alberta, Canada, better understand and apply fundamental concepts and skills. The major goals of the program are: (1) to develop in students an understanding of the interconnecting ideas and principles that transcend and unify the natural science…

  1. Aerospace Medicine and Biology: A Continuing Bibliography with Indexes, Supplement 194

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Articles on the biological, physiological, psychological, and environmental effects to which man is subjected to during and following simulated or actual flight in the earth's atmosphere or in interplanetary space are presented. The emphasis is on applied research more than fundamental studies or theoretical principles.

  2. Report of the Action Committee on Agricultural Education.

    ERIC Educational Resources Information Center

    Taylor, Robert E.

    This report is presented in four parts. Part one presents a philosophy of agricultural education. Part two describes the role of the biological sciences in agricultural education, important biological principles and concepts, and suggested programs for prospective students. Part three includes a discussion of the role of mathematics, chemistry and…

  3. An Experience Teaching an Undergraduate Level Course in Biophysics

    ERIC Educational Resources Information Center

    Feizabadi, Mitra Shojania

    2009-01-01

    The importance of including concepts, examples, and techniques from mathematics and the physical and information sciences in biology courses to fulfill the need of today's undergraduates has been the principle motivation for developing interdisciplinary biology-focused courses. Although this movement started many years ago, developing and offering…

  4. Fundamental Approaches in Molecular Biology for Communication Sciences and Disorders

    ERIC Educational Resources Information Center

    Bartlett, Rebecca S.; Jette, Marie E.; King, Suzanne N.; Schaser, Allison; Thibeault, Susan L.

    2012-01-01

    Purpose: This contemporary tutorial will introduce general principles of molecular biology, common deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein assays and their relevance in the field of communication sciences and disorders. Method: Over the past 2 decades, knowledge of the molecular pathophysiology of human disease has…

  5. Mendel's Modern Legacy

    ERIC Educational Resources Information Center

    Dixon, James; Kuldell, Natalie

    2012-01-01

    Genetic engineering is taught in biology--but as a scientific tool and not as a means to explore engineering design. Yet, given the clever behaviors and patterns that can be found when examining living systems, biology classes seem well positioned to teach foundational engineering design principles (Kuldell 2007). This article examines a new,…

  6. ``Dissection'' of a Hair Dryer

    NASA Astrophysics Data System (ADS)

    Eisenstein, Stan; Simpson, Jeff

    2008-12-01

    The electrical design of the common hair dryer is based almost entirely on relatively simple principles learned in introductory physics classes. Just as biology students dissect a frog to see the principles of anatomy in action, physics students can "dissect" a hair dryer to see how principles of electricity are used in a real system. They can discover how engineers solve problems such as how to vary between low and high heat and fan speed by simply moving the position of a single switch. Principles of alternating versus direct current, series and parallel circuits, electrical safety, voltage dividing, ac rectification, power, and measurement of resistance and continuity all come in to play.

  7. Molecular Cooperativity Governs Diverse and Monoallelic Olfactory Receptor Expression

    NASA Astrophysics Data System (ADS)

    Xing, Jianhua; Tian, Xiaojun; Zhang, Hang; Sannerud, Jens

    Multiple-objective optimization is common in biological systems. In the mammalian olfactory system, each sensory neuron stochastically expresses only one out of up to thousands of olfactory receptor (OR) gene alleles; at organism level the types of expressed ORs need to be maximized. The molecular mechanism of this Nobel-Prize winning puzzle remains unresolved after decades of extensive studies. Existing models focus only on monoallele activation, and cannot explain recent observations in mutants, especially the reduced global diversity of expressed ORs in G9a/GLP knockouts. In this work we integrated existing information on OR expression, and proposed an evolutionarily optimized three-layer regulation mechanism, which includes zonal segregation, epigenetic and enhancer competition coupled to a negative feedback loop. This model not only recapitulates monoallelic OR expression, but also elucidates how the olfactory system maximizes and maintains the diversity of OR expression. The model is validated by several experimental results, and particularly underscores cooperativity and synergy as a general design principle of multi-objective optimization in biology. The work is supported by the NIGMS/DMS Mathematical Biology program.

  8. Pacific Northwest Laboratory annual report for 1989 to the DOE Office of Energy Research - Part 1: Biomedical Sciences

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, J.F.

    This report summarizes progress on OHER human health, biological, general life sciences, and medical applications research programs conducted at PNL in FY 1989. The research develops the knowledge and scientific principles necessary to identify, understand, and anticipate the long-term health consequences of energy-related radiation and chemicals. Our continuing emphasis is to decrease the uncertainty of health risk estimates from existing and developing energy-related technologies through an increased understanding of how radiation and chemicals cause biological damage. The sequence of this report of PNL research reflects the OHER programmatic structure. The first section, on human health research, concerns statistical and epidemiologicalmore » studies for assessing health risks. The next section contains reports of biological research in laboratory animals and in vitro cell systems, including research with radionuclides and chemicals. The general life sciences research section reports research conducted for the OHER human genome research program, and the medical applications section summarizes commercial radioisotope production and distribution activities at DOE facilities. 6 refs., 50 figs., 35 tabs.« less

  9. Regeneration of the lung: Lung stem cells and the development of lung mimicking devices.

    PubMed

    Schilders, Kim A A; Eenjes, Evelien; van Riet, Sander; Poot, André A; Stamatialis, Dimitrios; Truckenmüller, Roman; Hiemstra, Pieter S; Rottier, Robbert J

    2016-04-23

    Inspired by the increasing burden of lung associated diseases in society and an growing demand to accommodate patients, great efforts by the scientific community produce an increasing stream of data that are focused on delineating the basic principles of lung development and growth, as well as understanding the biomechanical properties to build artificial lung devices. In addition, the continuing efforts to better define the disease origin, progression and pathology by basic scientists and clinicians contributes to insights in the basic principles of lung biology. However, the use of different model systems, experimental approaches and readout systems may generate somewhat conflicting or contradictory results. In an effort to summarize the latest developments in the lung epithelial stem cell biology, we provide an overview of the current status of the field. We first describe the different stem cells, or progenitor cells, residing in the homeostatic lung. Next, we focus on the plasticity of the different cell types upon several injury-induced activation or repair models, and highlight the regenerative capacity of lung cells. Lastly, we summarize the generation of lung mimics, such as air-liquid interface cultures, organoids and lung on a chip, that are required to test emerging hypotheses. Moreover, the increasing collaboration between distinct specializations will contribute to the eventual development of an artificial lung device capable of assisting reduced lung function and capacity in human patients.

  10. Adaptation of sensor morphology: an integrative view of perception from biologically inspired robotics perspective

    PubMed Central

    Nurzaman, Surya G.

    2016-01-01

    Sensor morphology, the morphology of a sensing mechanism which plays a role of shaping the desired response from physical stimuli from surroundings to generate signals usable as sensory information, is one of the key common aspects of sensing processes. This paper presents a structured review of researches on bioinspired sensor morphology implemented in robotic systems, and discusses the fundamental design principles. Based on literature review, we propose two key arguments: first, owing to its synthetic nature, biologically inspired robotics approach is a unique and powerful methodology to understand the role of sensor morphology and how it can evolve and adapt to its task and environment. Second, a consideration of an integrative view of perception by looking into multidisciplinary and overarching mechanisms of sensor morphology adaptation across biology and engineering enables us to extract relevant design principles that are important to extend our understanding of the unfinished concepts in sensing and perception. PMID:27499843

  11. Quantum Information Biology: From Theory of Open Quantum Systems to Adaptive Dynamics

    NASA Astrophysics Data System (ADS)

    Asano, Masanari; Basieva, Irina; Khrennikov, Andrei; Ohya, Masanori; Tanaka, Yoshiharu; Yamato, Ichiro

    This chapter reviews quantum(-like) information biology (QIB). Here biology is treated widely as even covering cognition and its derivatives: psychology and decision making, sociology, and behavioral economics and finances. QIB provides an integrative description of information processing by bio-systems at all scales of life: from proteins and cells to cognition, ecological and social systems. Mathematically QIB is based on the theory of adaptive quantum systems (which covers also open quantum systems). Ideologically QIB is based on the quantum-like (QL) paradigm: complex bio-systems process information in accordance with the laws of quantum information and probability. This paradigm is supported by plenty of statistical bio-data collected at all bio-scales. QIB re ects the two fundamental principles: a) adaptivity; and, b) openness (bio-systems are fundamentally open). In addition, quantum adaptive dynamics provides the most generally possible mathematical representation of these principles.

  12. Rational Design of an Ultrasensitive Quorum-Sensing Switch.

    PubMed

    Zeng, Weiqian; Du, Pei; Lou, Qiuli; Wu, Lili; Zhang, Haoqian M; Lou, Chunbo; Wang, Hongli; Ouyang, Qi

    2017-08-18

    One of the purposes of synthetic biology is to develop rational methods that accelerate the design of genetic circuits, saving time and effort spent on experiments and providing reliably predictable circuit performance. We applied a reverse engineering approach to design an ultrasensitive transcriptional quorum-sensing switch. We want to explore how systems biology can guide synthetic biology in the choice of specific DNA sequences and their regulatory relations to achieve a targeted function. The workflow comprises network enumeration that achieves the target function robustly, experimental restriction of the obtained candidate networks, global parameter optimization via mathematical analysis, selection and engineering of parts based on these calculations, and finally, circuit construction based on the principles of standardization and modularization. The performance of realized quorum-sensing switches was in good qualitative agreement with the computational predictions. This study provides practical principles for the rational design of genetic circuits with targeted functions.

  13. Introduction to bioengineering: melding of engineering and biological sciences.

    PubMed

    Shoureshi, Rahmat A

    2005-04-01

    Engineering has traditionally focused on the external extensions of organisms, such as transportation systems, high-rise buildings, and entertainment systems. In contrast, bioengineering is concerned with inward processes of biologic organisms. Utilization of engineering principles and techniques in the analysis and solution of problems in medicine and biology is the basis for bioengineering. This article discusses subspecialties in bioengineering and presents examples of projects in this discipline.

  14. Where statistics and molecular microarray experiments biology meet.

    PubMed

    Kelmansky, Diana M

    2013-01-01

    This review chapter presents a statistical point of view to microarray experiments with the purpose of understanding the apparent contradictions that often appear in relation to their results. We give a brief introduction of molecular biology for nonspecialists. We describe microarray experiments from their construction and the biological principles the experiments rely on, to data acquisition and analysis. The role of epidemiological approaches and sample size considerations are also discussed.

  15. Application of the Hard and Soft, Acids and Bases (HSAB) theory to toxicant--target interactions.

    PubMed

    Lopachin, Richard M; Gavin, Terrence; Decaprio, Anthony; Barber, David S

    2012-02-20

    Many chemical toxicants and/or their active metabolites are electrophiles that cause cell injury by forming covalent bonds with nucleophilic targets on biological macromolecules. Covalent reactions between nucleophilic and electrophilic reagents are, however, discriminatory since there is a significant degree of selectivity associated with these interactions. Over the course of the past few decades, the theory of Hard and Soft, Acids and Bases (HSAB) has proven to be a useful tool in predicting the outcome of such reactions. This concept utilizes the inherent electronic characteristic of polarizability to define, for example, reacting electrophiles and nucleophiles as either hard or soft. These HSAB definitions have been successfully applied to chemical-induced toxicity in biological systems. Thus, according to this principle, a toxic electrophile reacts preferentially with biological targets of similar hardness or softness. The soft/hard classification of a xenobiotic electrophile has obvious utility in discerning plausible biological targets and molecular mechanisms of toxicity. The purpose of this perspective is to discuss the HSAB theory of electrophiles and nucleophiles within a toxicological framework. In principle, covalent bond formation can be described by using the properties of their outermost or frontier orbitals. Because these orbital energies for most chemicals can be calculated using quantum mechanical models, it is possible to quantify the relative softness (σ) or hardness (η) of electrophiles or nucleophiles and to subsequently convert this information into useful indices of reactivity. This atomic level information can provide insight into the design of corroborative laboratory research and thereby help investigators discern corresponding molecular sites and mechanisms of toxicant action. The use of HSAB parameters has also been instrumental in the development and identification of potential nucleophilic cytoprotectants that can scavenge toxic electrophiles. Clearly, the difficult task of delineating molecular sites and mechanisms of toxicant action can be facilitated by the application of this quantitative approach.

  16. APPLICATION OF THE HARD AND SOFT, ACIDS AND BASES (HSAB) THEORY TO TOXICANT-TARGET INTERACTIONS

    PubMed Central

    LoPachin, Richard M.; Gavin, Terrence; DeCaprio, Anthony; Barber, David S.

    2011-01-01

    Many chemical toxicants and/or their active metabolites are electrophiles that cause cell injury by forming covalent bonds with nucleophilic targets on biological macromolecules. Covalent reactions between nucleophilic and electrophilic reagents are however discriminatory, since there is a significant degree of selectivity associated with these interactions. Over the course of the past few decades, the theory of Hard and Soft, Acid and Bases (HSAB) has proven to be a useful tool in predicting the outcome of such reactions. This concept utilizes the inherent electronic characteristic of polarizability to define, for example, reacting electrophiles and nucleophiles as either hard or soft. These HSAB definitions have been successfully applied to chemical-induced toxicity in biological systems. Thus, according to this principle, a toxic electrophile reacts preferentially with biological targets of similar hardness or softness. The soft/hard classification of a xenobiotic electrophile has obvious utility in discerning plausible biological targets and molecular mechanisms of toxicity. The purpose of this Perspective is to discuss the HSAB theory of electrophiles and nucleophiles within a toxicological framework. In principle, covalent bond formation can be described by using the properties of their outermost or frontier orbitals. Because these orbital energies for most chemicals can be calculated using quantum mechanical models, it is possible to quantify the relative softness (σ) or hardness (η) of electrophiles or nucleophiles and to subsequently convert this information into useful indices of reactivity. This atomic level information can provide insight into the design of corroborative laboratory research and thereby help investigators discern corresponding molecular sites and mechanisms of toxicant action. The use of HSAB parameters has also been instrumental in the development and identification of potential nucleophilic cytoprotectants that can scavenge toxic electrophiles. Clearly, the difficult task of delineating molecular sites and mechanisms of toxicant action can be facilitated by the application of this quantitative approach. PMID:22053936

  17. Colloquium: Biophysical principles of undulatory self-propulsion in granular media

    NASA Astrophysics Data System (ADS)

    Goldman, Daniel I.

    2014-07-01

    Biological locomotion, movement within environments through self-deformation, encompasses a range of time and length scales in an organism. These include the electrophysiology of the nervous system, the dynamics of muscle activation, the mechanics of the skeletal system, and the interaction mechanics of such structures within natural environments like water, air, sand, and mud. Unlike the many studies of cellular and molecular scale biophysical processes, movement of entire organisms (like flies, lizards, and snakes) is less explored. Further, while movement in fluids like air and water is also well studied, little is known in detail of the mechanics that organisms use to move on and within flowable terrestrial materials such as granular media, ensembles of small particles that collectively display solid, fluid, and gaslike behaviors. This Colloquium reviews recent progress to understand principles of biomechanics and granular physics responsible for locomotion of the sandfish, a small desert-dwelling lizard that "swims" within sand using undulation of its body. Kinematic and muscle activity measurements of sand swimming using high speed x-ray imaging and electromyography are discussed. This locomotion problem poses an interesting challenge: namely, that equations that govern the interaction of the lizard with its environment do not yet exist. Therefore, complementary modeling approaches are also described: resistive force theory for granular media, multiparticle simulation modeling, and robotic physical modeling. The models reproduce biomechanical and neuromechanical aspects of sand swimming and give insight into how effective locomotion arises from the coupling of the body movement and flow of the granular medium. The argument is given that biophysical study of movement provides exciting opportunities to investigate emergent aspects of living systems that might not depend sensitively on biological details.

  18. Common Origins of Diverse Misconceptions: Cognitive Principles and the Development of Biology Thinking

    PubMed Central

    Coley, John D.; Tanner, Kimberly D.

    2012-01-01

    Many ideas in the biological sciences seem especially difficult to understand, learn, and teach successfully. Our goal in this feature is to explore how these difficulties may stem not from the complexity or opacity of the concepts themselves, but from the fact that they may clash with informal, intuitive, and deeply held ways of understanding the world that have been studied for decades by psychologists. We give a brief overview of the field of developmental cognitive psychology. Then, in each of the following sections, we present a number of common challenges faced by students in the biological sciences. These may be in the form of misconceptions, biases, or simply concepts that are difficult to learn and teach, and they occur at all levels of biological analysis (molecular, cellular, organismal, population, and ecosystem). We then introduce the notion of a cognitive construal and discuss specific examples of how these cognitive principles may explain what makes some misconceptions so alluring and some biological concepts so challenging for undergraduates. We will argue that seemingly unrelated misconceptions may have common origins in a single underlying cognitive construal. These ideas emerge from our own ongoing cross-disciplinary conversation, and we think that expanding this conversation to include other biological scientists and educators, as well as other cognitive scientists, could have significant utility in improving biology teaching and learning. PMID:22949417

  19. Common origins of diverse misconceptions: cognitive principles and the development of biology thinking.

    PubMed

    Coley, John D; Tanner, Kimberly D

    2012-01-01

    Many ideas in the biological sciences seem especially difficult to understand, learn, and teach successfully. Our goal in this feature is to explore how these difficulties may stem not from the complexity or opacity of the concepts themselves, but from the fact that they may clash with informal, intuitive, and deeply held ways of understanding the world that have been studied for decades by psychologists. We give a brief overview of the field of developmental cognitive psychology. Then, in each of the following sections, we present a number of common challenges faced by students in the biological sciences. These may be in the form of misconceptions, biases, or simply concepts that are difficult to learn and teach, and they occur at all levels of biological analysis (molecular, cellular, organismal, population, and ecosystem). We then introduce the notion of a cognitive construal and discuss specific examples of how these cognitive principles may explain what makes some misconceptions so alluring and some biological concepts so challenging for undergraduates. We will argue that seemingly unrelated misconceptions may have common origins in a single underlying cognitive construal. These ideas emerge from our own ongoing cross-disciplinary conversation, and we think that expanding this conversation to include other biological scientists and educators, as well as other cognitive scientists, could have significant utility in improving biology teaching and learning.

  20. Development and Evaluation of a Fully-Online Introductory Biology Course With an Emphasis on the Possibility of Life Beyond Earth

    NASA Astrophysics Data System (ADS)

    Bratton, D., III; Mead, C.; Horodyskyj, L.; Anbar, A. D.

    2016-12-01

    BioBeyond, a fully-online introductory biology course, is distinguished by its driving narrative and its emphasis on education through exploration. BioBeyond applies the narrative, big-question, and active learning principles of its predecessor, Habitable Worlds, in the context of the disciplinarily constrained and higher enrollment environment of non-majors introductory biology. To align with the driving question "Are We Alone?" the course takes a novel approach to sequencing topics compared to typical introductory biology, exploring biological questions that arise from the main question in a narrative-driven format: What is life? How did it get so diverse? Was it always this way? What was the earliest life? What signatures does life leave behind? What is the future of life on Earth? Can humans survive the rigors of exploring other planets? To encourage construction and contextualization of new knowledge, critical thinking, scientific inquiry, and active learning, BioBeyond combines multiple features not often seen in introductory biology: a narrative centered around a big question, a continuous scoring system which assesses students as they learn rather than with high-stakes quizzes and tests, and, significantly, all of the learning experiences are adaptive and responsive, making use of Smart Sparrow's intelligent tutoring system. In Spring and Summer semesters of 2016, BioBeyond was deployed 34 times at 17 institutions nationwide, with another 56 classes at 17 institutions planned for Fall 2016. Each semester, feedback is collected and used to fuel a round of improvements. In addition, we are evaluating our course outcomes at five separate institutions of higher education, comparing the achievement of learning and development outcomes in BioBeyond to traditional offerings of introductory biology, using published concept inventories and surveys regarding interest in science, creative thinking, and scientific thinking. These results will also inform future development of BioBeyond and its planned sister courses.

  1. A tweaking principle for executive control: neuronal circuit mechanism for rule-based task switching and conflict resolution.

    PubMed

    Ardid, Salva; Wang, Xiao-Jing

    2013-12-11

    A hallmark of executive control is the brain's agility to shift between different tasks depending on the behavioral rule currently in play. In this work, we propose a "tweaking hypothesis" for task switching: a weak rule signal provides a small bias that is dramatically amplified by reverberating attractor dynamics in neural circuits for stimulus categorization and action selection, leading to an all-or-none reconfiguration of sensory-motor mapping. Based on this principle, we developed a biologically realistic model with multiple modules for task switching. We found that the model quantitatively accounts for complex task switching behavior: switch cost, congruency effect, and task-response interaction; as well as monkey's single-neuron activity associated with task switching. The model yields several testable predictions, in particular, that category-selective neurons play a key role in resolving sensory-motor conflict. This work represents a neural circuit model for task switching and sheds insights in the brain mechanism of a fundamental cognitive capability.

  2. Behavioral and neural Darwinism: selectionist function and mechanism in adaptive behavior dynamics.

    PubMed

    McDowell, J J

    2010-05-01

    An evolutionary theory of behavior dynamics and a theory of neuronal group selection share a common selectionist framework. The theory of behavior dynamics instantiates abstractly the idea that behavior is selected by its consequences. It implements Darwinian principles of selection, reproduction, and mutation to generate adaptive behavior in virtual organisms. The behavior generated by the theory has been shown to be quantitatively indistinguishable from that of live organisms. The theory of neuronal group selection suggests a mechanism whereby the abstract principles of the evolutionary theory may be implemented in the nervous systems of biological organisms. According to this theory, groups of neurons subserving behavior may be selected by synaptic modifications that occur when the consequences of behavior activate value systems in the brain. Together, these theories constitute a framework for a comprehensive account of adaptive behavior that extends from brain function to the behavior of whole organisms in quantitative detail. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  3. How quantitative measures unravel design principles in multi-stage phosphorylation cascades.

    PubMed

    Frey, Simone; Millat, Thomas; Hohmann, Stefan; Wolkenhauer, Olaf

    2008-09-07

    We investigate design principles of linear multi-stage phosphorylation cascades by using quantitative measures for signaling time, signal duration and signal amplitude. We compare alternative pathway structures by varying the number of phosphorylations and the length of the cascade. We show that a model for a weakly activated pathway does not reflect the biological context well, unless it is restricted to certain parameter combinations. Focusing therefore on a more general model, we compare alternative structures with respect to a multivariate optimization criterion. We test the hypothesis that the structure of a linear multi-stage phosphorylation cascade is the result of an optimization process aiming for a fast response, defined by the minimum of the product of signaling time and signal duration. It is then shown that certain pathway structures minimize this criterion. Several popular models of MAPK cascades form the basis of our study. These models represent different levels of approximation, which we compare and discuss with respect to the quantitative measures.

  4. Ecology, Microbial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Konopka, Allan

    2009-05-15

    Microbial ecology is a relatively young discipline within the field of microbiology. Its modern history spans just the past 60 years, and the field is defined by its emphasis on understanding the interactions of microbes with their environment, rather than their behavior under artificial laboratory conditions. Because microbes are ubiquitous, microbial ecologists study a broad diversity of habitats that range from aquatic to terrestrial to plant- or animal-associated. This has made it a challenge to identify unifying principles within the field. One approach is to recognize that although the activity of microbes in nature have effects at the macroscale, theymore » interact with their physical, chemical and biological milieu at a scale of micrometers. At this scale, several different microbial ecosystems can be defined, based upon association with particles, the presence of environmental gradients and the continuous availability of water. Principles applicable to microbial ecology reflect not only their population ecology and physiological ecology, but also their broad versatility and quantitative importance in the biosphere as biogeochemical catalysts and capacity for rapid physiological and evolutionary responses.« less

  5. Electrostatic Similarities between Protein and Small Molecule Ligands Facilitate the Design of Protein-Protein Interaction Inhibitors

    PubMed Central

    Zhang, Kam Y. J.

    2013-01-01

    One of the underlying principles in drug discovery is that a biologically active compound is complimentary in shape and molecular recognition features to its receptor. This principle infers that molecules binding to the same receptor may share some common features. Here, we have investigated whether the electrostatic similarity can be used for the discovery of small molecule protein-protein interaction inhibitors (SMPPIIs). We have developed a method that can be used to evaluate the similarity of electrostatic potentials between small molecules and known protein ligands. This method was implemented in a software called EleKit. Analyses of all available (at the time of research) SMPPII structures indicate that SMPPIIs bear some similarities of electrostatic potential with the ligand proteins of the same receptor. This is especially true for the more polar SMPPIIs. Retrospective analysis of several successful SMPPIIs has shown the applicability of EleKit in the design of new SMPPIIs. PMID:24130741

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Konopka, Allan

    Microbial ecology is a relatively young discipline within the field of microbiology. Its modern history spans just the past 60 years, and the field is defined by its emphasis on understanding the interactions of microbes with their environment, rather than their behavior under artificial laboratory conditions. Because microbes are ubiquitous, microbial ecologists study a broad diversity of habitats that range from aquatic to terrestrial to plant- or animal-associated. This has made it a challenge to identify unifying principles within the field. One approach is to recognize that although the activity of microbes in nature have effects at the macroscale, theymore » interact with their physical, chemical and biological milieu at a scale of micrometers. At this scale, several different microbial ecosystems can be defined, based upon association with particles, the presence of environmental gradients and the continuous availability of water. Principles applicable to microbial ecology reflect not only their population ecology and physiological ecology, but also their broad versatility and quantitative importance in the biosphere as biogeochemical catalysts and capacity for rapid physiological and evolutionary responses.« less

  7. Biological Dual-Use Research and Synthetic Biology of Yeast.

    PubMed

    Cirigliano, Angela; Cenciarelli, Orlando; Malizia, Andrea; Bellecci, Carlo; Gaudio, Pasquale; Lioj, Michele; Rinaldi, Teresa

    2017-04-01

    In recent years, the publication of the studies on the transmissibility in mammals of the H5N1 influenza virus and synthetic genomes has triggered heated and concerned debate within the community of scientists on biological dual-use research; these papers have raised the awareness that, in some cases, fundamental research could be directed to harmful experiments, with the purpose of developing a weapon that could be used by a bioterrorist. Here is presented an overview regarding the dual-use concept and its related international agreements which underlines the work of the Australia Group (AG) Export Control Regime. It is hoped that the principles and activities of the AG, that focuses on export control of chemical and biological dual-use materials, will spread and become well known to academic researchers in different countries, as they exchange biological materials (i.e. plasmids, strains, antibodies, nucleic acids) and scientific papers. To this extent, and with the aim of drawing the attention of the scientific community that works with yeast to the so called Dual-Use Research of Concern, this article reports case studies on biological dual-use research and discusses a synthetic biology applied to the yeast Saccharomyces cerevisiae, namely the construction of the first eukaryotic synthetic chromosome of yeast and the use of yeast cells as a factory to produce opiates. Since this organism is considered harmless and is not included in any list of biological agents, yeast researchers should take simple actions in the future to avoid the sharing of strains and advanced technology with suspicious individuals.

  8. Evolutionary molecular medicine.

    PubMed

    Nesse, Randolph M; Ganten, Detlev; Gregory, T Ryan; Omenn, Gilbert S

    2012-05-01

    Evolution has long provided a foundation for population genetics, but some major advances in evolutionary biology from the twentieth century that provide foundations for evolutionary medicine are only now being applied in molecular medicine. They include the need for both proximate and evolutionary explanations, kin selection, evolutionary models for cooperation, competition between alleles, co-evolution, and new strategies for tracing phylogenies and identifying signals of selection. Recent advances in genomics are transforming evolutionary biology in ways that create even more opportunities for progress at its interfaces with genetics, medicine, and public health. This article reviews 15 evolutionary principles and their applications in molecular medicine in hopes that readers will use them and related principles to speed the development of evolutionary molecular medicine.

  9. Climbing with adhesion: from bioinspiration to biounderstanding

    PubMed Central

    Cutkosky, Mark R.

    2015-01-01

    Bioinspiration is an increasingly popular design paradigm, especially as robots venture out of the laboratory and into the world. Animals are adept at coping with the variability that the world imposes. With advances in scientific tools for understanding biological structures in detail, we are increasingly able to identify design features that account for animals' robust performance. In parallel, advances in fabrication methods and materials are allowing us to engineer artificial structures with similar properties. The resulting robots become useful platforms for testing hypotheses about which principles are most important. Taking gecko-inspired climbing as an example, we show that the process of extracting principles from animals and adapting them to robots provides insights for both robotics and biology. PMID:26464786

  10. Complexity-aware simple modeling.

    PubMed

    Gómez-Schiavon, Mariana; El-Samad, Hana

    2018-02-26

    Mathematical models continue to be essential for deepening our understanding of biology. On one extreme, simple or small-scale models help delineate general biological principles. However, the parsimony of detail in these models as well as their assumption of modularity and insulation make them inaccurate for describing quantitative features. On the other extreme, large-scale and detailed models can quantitatively recapitulate a phenotype of interest, but have to rely on many unknown parameters, making them often difficult to parse mechanistically and to use for extracting general principles. We discuss some examples of a new approach-complexity-aware simple modeling-that can bridge the gap between the small-scale and large-scale approaches. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Conferring biological activity to native spider silk: A biofunctionalized protein-based microfiber.

    PubMed

    Wu, Hsuan-Chen; Quan, David N; Tsao, Chen-Yu; Liu, Yi; Terrell, Jessica L; Luo, Xiaolong; Yang, Jen-Chang; Payne, Gregory F; Bentley, William E

    2017-01-01

    Spider silk is an extraordinary material with physical properties comparable to the best scaffolding/structural materials, and as a fiber it can be manipulated with ease into a variety of configurations. Our work here demonstrates that natural spider silk fibers can also be used to organize biological components on and in devices through rapid and simple means. Micron scale spider silk fibers (5-10 μm in diameter) were surface modified with a variety of biological entities engineered with pentaglutamine tags via microbial transglutaminase (mTG). Enzymes, enzyme pathways, antibodies, and fluorescent proteins were all assembled onto spider silk fibers using this biomolecular engineering/biofabrication process. Additionally, arrangement of biofunctionalized fiber should in of itself generate a secondary level of biomolecular organization. Toward this end, as proofs of principle, spatially defined arrangement of biofunctionalized spider silk fiber was shown to generate effects specific to silk position in two cases. In one instance, arrangement perpendicular to a flow produced selective head and neck carcinoma cell capture on silk with antibodies complexed to conjugated protein G. In a second scenario, asymmetric bacterial chemotaxis arose from asymmetric conjugation of enzymes to arranged silk. Overall, the biofabrication processes used here were rapid, required no complex chemistries, were biologically benign, and also the resulting engineered silk microfibers were flexible, readily manipulated and functionally active. Deployed here in microfluidic environments, biofunctional spider silk fiber provides a means to convey complex biological functions over a range of scales, further extending its potential as a biomaterial in biotechnological settings. Biotechnol. Bioeng. 2017;114: 83-95. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Use of Case Studies to Introduce Undergraduate Students to Principles of Food Microbiology, Molecular Biology, and Epidemiology of Food-Borne Disease

    ERIC Educational Resources Information Center

    Ponder, Monica A.; Sumner, Susan

    2009-01-01

    Mock outbreaks of infectious disease offer the ability to introduce principles of food microbiology, ecology, and epidemiology to undergraduate students using an inquiry driven process. Students were presented with an epidemiological case study detailing patient history, clinical presentation, and foods recently consumed. The students then had to…

  13. Content vs. Learning: An Old Dichotomy in Science Courses

    ERIC Educational Resources Information Center

    Bergtrom, Gerald

    2011-01-01

    The principles of course redesign that were applied to a gateway Cell Biology course at the University of Wisconsin-Milwaukee are applicable to courses large and small, and to institutions of any size. The challenge was to design a content-rich science course that kept pace with present and future content and at the same time use principles of…

  14. Target Capabilities List: A Companion to the National Preparedness Guidelines

    DTIC Science & Technology

    2007-09-01

    lowest possible geographic, organizational, and jurisdictional level using the principles in the National Incident Management System (NIMS). The...Response Plan. U.S. Department of Homeland Security. December 2004. 3. Biological Incident Annex. In the National Response Plan. U.S. Department of...elements of the continuum and improve interoperability, public safety and service agency practitioners should observe the following principles : Gain

  15. Evolution of microbes and viruses: a paradigm shift in evolutionary biology?

    PubMed Central

    Koonin, Eugene V.; Wolf, Yuri I.

    2012-01-01

    When Charles Darwin formulated the central principles of evolutionary biology in the Origin of Species in 1859 and the architects of the Modern Synthesis integrated these principles with population genetics almost a century later, the principal if not the sole objects of evolutionary biology were multicellular eukaryotes, primarily animals and plants. Before the advent of efficient gene sequencing, all attempts to extend evolutionary studies to bacteria have been futile. Sequencing of the rRNA genes in thousands of microbes allowed the construction of the three- domain “ribosomal Tree of Life” that was widely thought to have resolved the evolutionary relationships between the cellular life forms. However, subsequent massive sequencing of numerous, complete microbial genomes revealed novel evolutionary phenomena, the most fundamental of these being: (1) pervasive horizontal gene transfer (HGT), in large part mediated by viruses and plasmids, that shapes the genomes of archaea and bacteria and call for a radical revision (if not abandonment) of the Tree of Life concept, (2) Lamarckian-type inheritance that appears to be critical for antivirus defense and other forms of adaptation in prokaryotes, and (3) evolution of evolvability, i.e., dedicated mechanisms for evolution such as vehicles for HGT and stress-induced mutagenesis systems. In the non-cellular part of the microbial world, phylogenomics and metagenomics of viruses and related selfish genetic elements revealed enormous genetic and molecular diversity and extremely high abundance of viruses that come across as the dominant biological entities on earth. Furthermore, the perennial arms race between viruses and their hosts is one of the defining factors of evolution. Thus, microbial phylogenomics adds new dimensions to the fundamental picture of evolution even as the principle of descent with modification discovered by Darwin and the laws of population genetics remain at the core of evolutionary biology. PMID:22993722

  16. Novel analgesic triglycerides from cultures of Agaricus macrosporus and other basidiomycetes as selective inhibitors of neurolysin.

    PubMed

    Stadler, Marc; Hellwig, Veronika; Mayer-Bartschmid, Anke; Denzer, Dirk; Wiese, Burkhard; Burkhardt, Nils

    2005-12-01

    The agaricoglycerides are a new class of fungal secondary metabolites that constitute esters of chlorinated 4-hydroxy benzoic acid and glycerol. They are produced in cultures of the edible mushroom, Agaricus macrosporus, and several other basidiomycetes of the genera Agaricus, Hypholoma, Psathyrella and Stropharia. The main active principle, agaricoglyceride A, showed strong activities against neurolysin, a protease involved in the regulation of dynorphin and neurotensin metabolism (IC50 = 200 nM), and even exhibited moderate analgesic in vivo activities in an in vivo model. Agaricoglyceride monoacetates (IC50 = 50 nM) showed even stronger in vitro activities. Several further co-metabolites with weaker or lacking bioactivities were also obtained and characterized. Among those were further agaricoglyceride derivatives, as well as further chlorinated phenol derivatives such as the new compound, agaricic ester. The characteristics of the producer organisms, the isolation of bioactive metabolites from cultures of A. macrosporus, their biological activities, and preliminary results on their occurrence in basidiomycetes, are described.

  17. Neurons for hunger and thirst transmit a negative-valence teaching signal

    PubMed Central

    Gong, Rong; Magnus, Christopher J.; Yu, Yang; Sternson, Scott M.

    2015-01-01

    Homeostasis is a biological principle for regulation of essential physiological parameters within a set range. Behavioural responses due to deviation from homeostasis are critical for survival, but motivational processes engaged by physiological need states are incompletely understood. We examined motivational characteristics and dynamics of two separate neuron populations that regulate energy and fluid homeostasis by using cell type-specific activity manipulations in mice. We found that starvation-sensitive AGRP neurons exhibit properties consistent with a negative-valence teaching signal. Mice avoided activation of AGRP neurons, indicating that AGRP neuron activity has negative valence. AGRP neuron inhibition conditioned preference for flavours and places. Correspondingly, deep-brain calcium imaging revealed that AGRP neuron activity rapidly reduced in response to food-related cues. Complementary experiments activating thirst-promoting neurons also conditioned avoidance. Therefore, these need-sensing neurons condition preference for environmental cues associated with nutrient or water ingestion, which is learned through reduction of negative-valence signals during restoration of homeostasis. PMID:25915020

  18. Active colloids as assembly machines

    NASA Astrophysics Data System (ADS)

    Goodrich, Carl; Brenner, Michael

    Controlling motion at the microscopic scale is a fundamental goal in the development of biologically-inspired systems. We show that the motion of active, self-propelled colloids can be sufficiently controlled for use as a tool to assemble complex structures such as braids and weaves out of microscopic filaments. Unlike typical self-assembly paradigms, these structures are held together by geometric constraints rather than adhesive bonds. The out-of-equilibrium assembly that we propose involves precisely controlling the two-dimensional motion of active colloids so that their path has a non-trivial topology. We demonstrate with proof-of-principle Brownian dynamics simulations that, when the colloids are attached to long semi-flexible filaments, this motion causes the filaments to braid. The ability of the active particles to provide sufficient force necessary to bend the filaments into a braid depends on a number of factors, including the self-propulsion mechanism, the properties of the filament, and the maximum curvature in the braid. Our work demonstrates that non-equilibrium assembly pathways can be designed using active particles.

  19. Enzymatically Active Microgels from Self-Assembling Protein Nanofibrils for Microflow Chemistry

    PubMed Central

    2015-01-01

    Amyloid fibrils represent a generic class of protein structure associated with both pathological states and with naturally occurring functional materials. This class of protein nanostructure has recently also emerged as an excellent foundation for sophisticated functional biocompatible materials including scaffolds and carriers for biologically active molecules. Protein-based materials offer the potential advantage that additional functions can be directly incorporated via gene fusion producing a single chimeric polypeptide that will both self-assemble and display the desired activity. To succeed, a chimeric protein system must self-assemble without the need for harsh triggering conditions which would damage the appended functional protein molecule. However, the micrometer to nanoscale patterning and morphological control of protein-based nanomaterials has remained challenging. This study demonstrates a general approach for overcoming these limitations through the microfluidic generation of enzymatically active microgels that are stabilized by amyloid nanofibrils. The use of scaffolds formed from biomaterials that self-assemble under mild conditions enables the formation of catalytic microgels while maintaining the integrity of the encapsulated enzyme. The enzymatically active microgel particles show robust material properties and their porous architecture allows diffusion in and out of reactants and products. In combination with microfluidic droplet trapping approaches, enzymatically active microgels illustrate the potential of self-assembling materials for enzyme immobilization and recycling, and for biological flow-chemistry. These design principles can be adopted to create countless other bioactive amyloid-based materials with diverse functions. PMID:26030507

  20. Community Relations: DOD’s Approach for Using Resources Reflects Sound Management Principles

    DTIC Science & Technology

    2016-09-01

    COMMUNITY RELATIONS DOD’s Approach for Using Resources Reflects Sound Management Principles Report to...Sound Management Principles What GAO Found The Department of Defense’s (DOD) approach for determining which community relations activities to...undertake reflects sound management principles —both for activities requested by non-DOD entities and for activities initiated by the department. DOD and

  1. Box 11: Tissue Engineering and Bioscience Methods Using Proton Beam Writing

    NASA Astrophysics Data System (ADS)

    van Kan, J. A.

    Tissue engineering is a rapidly developing and highly interdisciplinary field that applies the principles of cell biology, engineering, and materials science to the culture of biological tissue. The artificially grown tissue then can be implanted directly into the body, or it can form part of a device that replaces organ functionality.

  2. Experimentally Guided Models Reveal Replication Principles that Shape the Mutation Distribution of RNA Viruses

    DTIC Science & Technology

    2015-01-30

    intracel- lular replication. Two classic replication modes have been described for single-stranded RNA viruses: the ‘stamping machine’ mode ( Stent ...Journal of Theoretical Biology 218:309–321. doi: 10.1006/jtbi.2002.3078. Stent GS. 1963. Molecular Biology of Bacterial Viruses. San Francisco, Calif: W H

  3. Using the Principles of SoTL to Redesign an Advanced Evolutionary Biology Course

    ERIC Educational Resources Information Center

    deBraga, Michael; Boyd, Cleo; Abdulnour, Shahad

    2015-01-01

    A primary goal of university instruction is the students' demonstration of improved, highly developed critical thinking (CT) skills. However, how do faculty encourage CT and its potential concomitant increase in student workload without negatively impacting student perceptions of the course? In this investigation, an advanced biology course is…

  4. Using the Principles of "BIO2010" to Develop an Introductory, Interdisciplinary Course for Biology Students

    ERIC Educational Resources Information Center

    Matthews, Kelly E.; Adams, Peter; Goos, Merrilyn

    2010-01-01

    Modern biological sciences require practitioners to have increasing levels of knowledge, competence, and skills in mathematics and programming. A recent review of the science curriculum at the University of Queensland, a large, research-intensive institution in Australia, resulted in the development of a more quantitatively rigorous undergraduate…

  5. Human Food Consumption: A Primer on Nonequilibrium Thermodynamics for College Physics

    ERIC Educational Resources Information Center

    Zurcher, Ulrich

    2008-01-01

    Students often have great difficulties with applications of the energy principle, especially those from biology, although most introductory physics texts include a brief discussion of metabolism. We point out that many of these discussions are unsatisfactory, since they often fail to mention how biological systems are "thermal systems in…

  6. Queueing-Based Synchronization and Entrainment for Synthetic Gene Oscillators

    NASA Astrophysics Data System (ADS)

    Mather, William; Butzin, Nicholas; Hochendoner, Philip; Ogle, Curtis

    Synthetic gene oscillators have been a major focus of synthetic biology research since the beginning of the field 15 years ago. They have proven to be useful both for biotechnological applications as well as a testing ground to significantly develop our understanding of the design principles behind synthetic and native gene oscillators. In particular, the principles governing synchronization and entrainment of biological oscillators have been explored using a synthetic biology approach. Our work combines experimental and theoretical approaches to specifically investigate how a bottleneck for protein degradation, which is present in most if not all existing synthetic oscillators, can be leveraged to robustly synchronize and entrain biological oscillators. We use both the terminology and mathematical tools of queueing theory to intuitively explain the role of this bottleneck in both synchronization and entrainment, which extends prior work demonstrating the usefulness of queueing theory in synthetic and native gene circuits. We conclude with an investigation of how synchronization and entrainment may be sensitive to the presence of multiple proteolytic pathways in a cell that couple weakly through crosstalk. This work was supported by NSF Grant #1330180.

  7. Macroscopic Biological Characteristics of Individualized Therapy in Chinese Mongolian Osteopathy

    NASA Astrophysics Data System (ADS)

    Namula, Zhao; Mei, Wang; Li, Xue-en

    Objective: Chinese Mongolian osteopathy has been passed down from ancient times and includes unique practices and favorable efficacy. In this study, we investigate the macroscopic biological characteristics of individualized Chinese Mongolian osteopathy, in order to provide new principle and methods for the treatment of bone fracture. Method: With a view to provide a vital link between nature and humans, the four stages of Chinese Mongolian osteopathy focus on the unity of the mind and body, the limbs and body organs, the body and its functions, and humans and nature. Results: We discuss the merits of individualized osteopathy in terms of the underlying concepts, and evaluate the approaches and principles of traditional medicine, as well as biomechanics. Conclusions: Individualized Mongolian osteopathy targets macroscopic biological components including dynamic reduction, natural fixation, and functional healing. Chinese Mongolian osteopathy is a natural, ecological and non-invasive osteopathy that values the link between nature and humans, including the unity of mind and body. The biological components not only serve as a foundation for Chinese Mongolian osteopathy but are also important for the future development of modern osteopathy, focusing on individualization, actualization and integration.

  8. Shape changing thin films powered by DNA hybridization

    NASA Astrophysics Data System (ADS)

    Shim, Tae Soup; Estephan, Zaki G.; Qian, Zhaoxia; Prosser, Jacob H.; Lee, Su Yeon; Chenoweth, David M.; Lee, Daeyeon; Park, So-Jung; Crocker, John C.

    2017-01-01

    Active materials that respond to physical and chemical stimuli can be used to build dynamic micromachines that lie at the interface between biological systems and engineered devices. In principle, the specific hybridization of DNA can be used to form a library of independent, chemically driven actuators for use in such microrobotic applications and could lead to device capabilities that are not possible with polymer- or metal-layer-based approaches. Here, we report shape changing films that are powered by DNA strand exchange reactions with two different domains that can respond to distinct chemical signals. The films are formed from DNA-grafted gold nanoparticles using a layer-by-layer deposition process. Films consisting of an active and a passive layer show rapid, reversible curling in response to stimulus DNA strands added to solution. Films consisting of two independently addressable active layers display a complex suite of repeatable transformations, involving eight mechanochemical states and incorporating self-righting behaviour.

  9. Peptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins

    PubMed Central

    Dallas, David C.; Citerne, Florine; Tian, Tian; Silva, Vitor L. M.; Kalanetra, Karen M.; Frese, Steven A.; Robinson, Randall C.; Mills, David A.; Barile, Daniela

    2015-01-01

    Scope The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins. Methods and results Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1,500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species. Conclusion The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases. PMID:26616950

  10. Insight into the C-F bond mechanism of molecular analogs for antibacterial drug design.

    PubMed

    Liu, Junna; Lv, Biyu; Liu, Huaqing; Li, Xin; Yin, Weiping

    2018-06-01

    The activities of biological molecules usually rely on both of intra-molecular and intermolecular interactions between their function groups. These interactions include interonic attraction theory, Van der Waal's forces and the function of geometry on the individual molecules, whether they are naturally or synthetic. The purpose of this study was to evaluate the antibacterial activity of C-F bond compound using combination of experiments verification and theoretical calculation. We target on the insect natural products from the maggots of Chrysomyis megacephala Fabricius. Based on density functional theory(DFT) and B3LYP method, a theoretical study of the C-F bond on fluoride was designed to explore compounds 2 and 4 antibacterial structure-activity relationship. With the progress in DFT, first-principle calculation based on DFT has gradually become a routine method for drug design, quantum chemistry and other science fields.

  11. Homeostatic control of neural activity: from phenomenology to molecular design.

    PubMed

    Davis, Graeme W

    2006-01-01

    Homeostasis is a specialized form of regulation that precisely maintains the function of a system at a set point level of activity. Recently, homeostatic signaling has been suggested to control neural activity through the modulation of synaptic efficacy and membrane excitability ( Davis & Goodman 1998a, Turrigiano & Nelson 2000, Marder & Prinz 2002, Perez-Otano & Ehlers 2005 ). In this way, homeostatic signaling is thought to constrain neural plasticity and contribute to the stability of neural function over time. Using a restrictive definition of homeostasis, this review first evaluates the phenomenological and molecular evidence for homeostatic signaling in the nervous system. Then, basic principles underlying the design and molecular implementation of homeostatic signaling are reviewed on the basis of work in other, simplified biological systems such as bacterial chemotaxis and the heat shock response. Data from these systems are then discussed in the context of homeostatic signaling in the nervous system.

  12. Primary hypertension is a disease of premature vascular aging associated with neuro-immuno-metabolic abnormalities.

    PubMed

    Litwin, Mieczysław; Feber, Janusz; Niemirska, Anna; Michałkiewicz, Jacek

    2016-02-01

    There is an increasing amount of data indicating that primary hypertension (PH) is not only a hemodynamic phenomenon but also a complex syndrome involving abnormal fat tissue distribution, over-activity of the sympathetic nervous system (SNS), metabolic abnormalities, and activation of the immune system. In children, PH usually presents with a typical phenotype of disturbed body composition, accelerated biological maturity, and subtle immunological and metabolic abnormalities. This stage of the disease is potentially reversible. However, long-lasting over-activity of the SNS and immuno-metabolic alterations usually lead to an irreversible stage of cardiovascular disease. We describe an intermediate phenotype of children with PH, showing that PH is associated with accelerated development, i.e., early premature aging of the immune, metabolic, and vascular systems. The associations and determinants of hypertensive organ damage, the principles of treatment, and the possibility of rejuvenation of the cardiovascular system are discussed.

  13. Peptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins.

    PubMed

    Dallas, David C; Citerne, Florine; Tian, Tian; Silva, Vitor L M; Kalanetra, Karen M; Frese, Steven A; Robinson, Randall C; Mills, David A; Barile, Daniela

    2016-04-15

    The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins. Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species. The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Klein bottle logophysics: a unified principle for non-linear systems, cosmology, geophysics, biology, biomechanics and perception

    NASA Astrophysics Data System (ADS)

    Lucio Rapoport, Diego

    2013-04-01

    We present a unified principle for science that surmounts dualism, in terms of torsion fields and the non-orientable surfaces, notably the Klein Bottle and its logic, the Möbius strip and the projective plane. We apply it to the complex numbers and cosmology, to non-linear systems integrating the issue of hyperbolic divergences with the change of orientability, to the biomechanics of vision and the mammal heart, to the morphogenesis of crustal shapes on Earth in connection to the wavefronts of gravitation, elasticity and electromagnetism, to pattern recognition of artificial images and visual recognition, to neurology and the topographic maps of the sensorium, to perception, in particular of music. We develop it in terms of the fundamental 2:1 resonance inherent to the Möbius strip and the Klein Bottle, the minimal surfaces representation of the wavefronts, and the non-dual Klein Bottle logic inherent to pattern recognition, to the harmonic functions and vector fields that lay at the basis of geophysics and physics at large. We discuss the relation between the topographic maps of the sensorium, and the issue of turning inside-out of the visual world as a general principle for cognition, topological chemistry, cell biology and biological morphogenesis in particular in embryology

  15. Scale relativity theory and integrative systems biology: 1. Founding principles and scale laws.

    PubMed

    Auffray, Charles; Nottale, Laurent

    2008-05-01

    In these two companion papers, we provide an overview and a brief history of the multiple roots, current developments and recent advances of integrative systems biology and identify multiscale integration as its grand challenge. Then we introduce the fundamental principles and the successive steps that have been followed in the construction of the scale relativity theory, and discuss how scale laws of increasing complexity can be used to model and understand the behaviour of complex biological systems. In scale relativity theory, the geometry of space is considered to be continuous but non-differentiable, therefore fractal (i.e., explicitly scale-dependent). One writes the equations of motion in such a space as geodesics equations, under the constraint of the principle of relativity of all scales in nature. To this purpose, covariant derivatives are constructed that implement the various effects of the non-differentiable and fractal geometry. In this first review paper, the scale laws that describe the new dependence on resolutions of physical quantities are obtained as solutions of differential equations acting in the scale space. This leads to several possible levels of description for these laws, from the simplest scale invariant laws to generalized laws with variable fractal dimensions. Initial applications of these laws to the study of species evolution, embryogenesis and cell confinement are discussed.

  16. On the Materials Science of Nature's Arms Race.

    PubMed

    Liu, Zengqian; Zhang, Zhefeng; Ritchie, Robert O

    2018-06-05

    Biological material systems have evolved unique combinations of mechanical properties to fulfill their specific function through a series of ingenious designs. Seeking lessons from Nature by replicating the underlying principles of such biological materials offers new promise for creating unique combinations of properties in man-made systems. One case in point is Nature's means of attack and defense. During the long-term evolutionary "arms race," naturally evolved weapons have achieved exceptional mechanical efficiency with a synergy of effective offense and persistence-two characteristics that often tend to be mutually exclusive in many synthetic systems-which may present a notable source of new materials science knowledge and inspiration. This review categorizes Nature's weapons into ten distinct groups, and discusses the unique structural and mechanical designs of each group by taking representative systems as examples. The approach described is to extract the common principles underlying such designs that could be translated into man-made materials. Further, recent advances in replicating the design principles of natural weapons at differing lengthscales in artificial materials, devices and tools to tackle practical problems are revisited, and the challenges associated with biological and bioinspired materials research in terms of both processing and properties are discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Physics of the gut: How polymers dynamically structure the gut environment

    NASA Astrophysics Data System (ADS)

    Preska Steinberg, Asher; Datta, Sujit; Bogatyrev, Said; Ismagilov, Rustem

    While the gut microbiome and biological regulation of the gut environment is being exhaustively studied by the microbiology community, little is known about the rich physics that governs the macro- and microstructure of the gut environment. The mammalian gut abounds in soft materials; ranging from soluble polymers (e.g. dietary fibers, therapeutic polymers and mucins) to colloidal matter (e.g. bacteria, viruses and nanoparticles carrying drugs). We have found experimentally that soluble polymers can dynamically re-structure the colonic mucus hydrogel by modulating its degree of swelling. We implemented a mean-field Flory-Huggins model to reveal that these polymer-mucus interactions can be captured using a simple, first principles thermodynamics model. In this model, the amount of deswelling increases with polymer concentration and size. We then used these physical principles to make predictions about how different polymer solutions affect the structure of mucus. Lastly, we explore applying this framework and similar physical principles to a variety of biological problems in the gut.

  18. Extension of in vivo half-life of biologically active peptides via chemical conjugation to XTEN protein polymer.

    PubMed

    Podust, Vladimir N; Sim, Bee-Cheng; Kothari, Dharti; Henthorn, Lana; Gu, Chen; Wang, Chia-wei; McLaughlin, Bryant; Schellenberger, Volker

    2013-11-01

    XTEN, unstructured biodegradable proteins, have been used to extend the in vivo half-life of genetically fused therapeutic proteins and peptides. To expand the applications of XTEN technology to half-life extension of other classes of molecules, XTEN protein polymers and methods for chemical XTENylation were developed. Two XTEN precursors were engineered to contain enzymatically removable purification tags. The proteins were readily expressed in bacteria and purified to homogeneity by chromatography techniques. As proof-of-principle, GLP2-2G peptide was chemically conjugated to each of the two XTEN protein polymers using maleimide-thiol chemistry. The monodisperse nature of XTEN protein polymer enabled reaction monitoring as well as the detection of peptide modifications in the conjugated state using reverse phase-high performance liquid chromatography (RP-HPLC) and electrospray ionization mass spectrometry. The resulting GLP2-2G-XTEN conjugates were purified by preparative RP-HPLC to homogeneity. In comparison with recombinantly fused GLP2-2G-XTEN, chemically conjugated GLP2-2G-XTEN molecules exhibited comparable in vitro activity, in vitro plasma stability and pharmacokinetics in rats. These data suggest that chemical XTENylation could effectively extend the half-life of a wide spectrum of biologically active molecules, therefore broadening its applicability.

  19. The Notion of Scientific Knowledge in Biology

    NASA Astrophysics Data System (ADS)

    Morante, Silvia; Rossi, Giancarlo

    2016-03-01

    The purpose of this work is to reconsider and critically discuss the conceptual foundations of modern biology and bio-sciences in general, and provide an epistemological guideline to help framing the teaching of these disciplines and enhancing the quality of their presentation in High School, Master and Ph.D. courses. After discussing the methodological problems that arise in trying to construct a sensible and useful scientific approach applicable to the study of living systems, we illustrate what are the general requirements that a workable scheme of investigation should meet to comply with the principles of the Galilean method. The amazing success of basic physics, the Galilean science of election, can be traced back to the development of a radically " reductionistic" approach in the interpretation of experiments and a systematic procedure tailored on the paradigm of " falsifiability" aimed at consistently incorporating new information into extended models/theories. The development of bio-sciences seems to fit with neither reductionism (the deeper is the level of description of a biological phenomenon the more difficult looks finding general and simple laws), nor falsifiability (not always experiments provide a yes-or-no answer). Should we conclude that biology is not a science in the Galilean sense? We want to show that this is not so. Rather in the study of living systems, the novel interpretative paradigm of " complexity" has been developed that, without ever conflicting with the basic principles of physics, allows organizing ideas, conceiving new models and understanding the puzzling lack of reproducibility that seems to affect experiments in biology and in other modern areas of investigation. In the delicate task of conveying scientific concepts and principles to students as well as in popularising bio-sciences to a wider audience, it is of the utmost importance for the success of the process of learning to highlight the internal logical consistency of biology and its compliance with the fundamental laws of physics.

  20. Common computational properties found in natural sensory systems

    NASA Astrophysics Data System (ADS)

    Brooks, Geoffrey

    2009-05-01

    Throughout the animal kingdom there are many existing sensory systems with capabilities desired by the human designers of new sensory and computational systems. There are a few basic design principles constantly observed among these natural mechano-, chemo-, and photo-sensory systems, principles that have been proven by the test of time. Such principles include non-uniform sampling and processing, topological computing, contrast enhancement by localized signal inhibition, graded localized signal processing, spiked signal transmission, and coarse coding, which is the computational transformation of raw data using broadly overlapping filters. These principles are outlined here with references to natural biological sensory systems as well as successful biomimetic sensory systems exploiting these natural design concepts.

  1. Umbrella sampling of proton transfer in a creatine-water system

    NASA Astrophysics Data System (ADS)

    Ivchenko, Olga; Bachert, Peter; Imhof, Petra

    2014-04-01

    Proton transfer reactions are among the most common processes in chemistry and biology. Proton transfer between creatine and surrounding solvent water is underlying the chemical exchange saturation transfer used as a contrast in magnetic resonance imaging. The free energy barrier, determined by first-principles umbrella sampling simulations (EaDFT 3 kcal/mol) is in the same order of magnitude as the experimentally obtained activation energy. The underlying mechanism is a first proton transfer from the guanidinium group to the water pool, followed by a second transition where a proton is "transferred back" from the nearest water molecule to the deprotonated nitrogen atom of creatine.

  2. Methods of analysis and separation of chiral flavonoids.

    PubMed

    Yáñez, Jaime A; Andrews, Preston K; Davies, Neal M

    2007-04-01

    Although the analysis of the enantiomers and epimers of chiral flavanones has been carried out for over 20 years, there often remains a deficit within the pharmaceutical, agricultural, and medical sciences to address this issue. Hence, despite increased interest in the potential therapeutic uses, plant physiology roles, and health-benefits of chiral flavanones, the importance of stereoselectivity in agricultural, nutrition, pharmacokinetic, pharmacodynamic, pharmacological activity and disposition has often been ignored. This review presents both the general principles that allow separation of chiral flavanones, and discusses both the advantages and disadvantages of the available chromatographic assay methods and procedures used to separately quantify flavanone enantiomers and epimers in biological matrices.

  3. Money, Sex, and Drugs: A Case Study to Teach the Genetics of Antibiotic Resistance

    PubMed Central

    Kuehner, Jason N.; Tong, Lillian; Miller, Sarah; Handelsman, Jo

    2008-01-01

    The goal of the work reported here was to help students expand their understanding of antibiotic resistance, the Central Dogma, and evolution. We developed a unit entitled “Ciprofloxacin Resistance in Neisseria gonorrhoeae,” which was constructed according to the principles of scientific teaching by a team of graduate students, science faculty, and instructors. A variety of activities and assessments were used, including a case study, short lectures, and group problem-solving. Implementation of “Ciprofloxacin Resistance in Neisseria gonorrhoeae” in a college freshman seminar suggests these materials are useful in increasing understanding of complex biological topics and improving problem-solving abilities. PMID:18765752

  4. Money, sex, and drugs: a case study to teach the genetics of antibiotic resistance.

    PubMed

    Cloud-Hansen, Karen A; Kuehner, Jason N; Tong, Lillian; Miller, Sarah; Handelsman, Jo

    2008-01-01

    The goal of the work reported here was to help students expand their understanding of antibiotic resistance, the Central Dogma, and evolution. We developed a unit entitled "Ciprofloxacin Resistance in Neisseria gonorrhoeae," which was constructed according to the principles of scientific teaching by a team of graduate students, science faculty, and instructors. A variety of activities and assessments were used, including a case study, short lectures, and group problem-solving. Implementation of "Ciprofloxacin Resistance in Neisseria gonorrhoeae" in a college freshman seminar suggests these materials are useful in increasing understanding of complex biological topics and improving problem-solving abilities.

  5. NanoShuttles: Harnessing Motor Proteins to Transport Cargo in Synthetic Environments

    NASA Astrophysics Data System (ADS)

    Vogel, V.; Hess, H.

    Motors have become a crucial commodity in our daily lives, from transportation to driving conveyor belts that enable the sequential assembly of cars and other industrial machines. For the sequential assembly of building blocks at the nanoscale that would not assemble spontaneously into larger functional systems, however, active transport systems are not yet available. In contrast, cells have evolved sophisticated molecular machinery that drives movement and active transport. Driven by the conversion of chemical into mechanical energy, namely through hydrolysis of the biological fuel ATP, molecular motors enable cells to operate far away from equilibrium by transporting organelles and molecules to designated locations within the cell, often against concentration gradients. Inspired by the biological concept of active transport, major efforts are underway to learn how to build nanoscale transport systems that are driven by molecular motors. Emerging engineering principles are discussed of how to build tracks and junctions to guide such nanoshuttles, how to load them with cargo and control their speed, how to use active transport to assemble mesoscopic structures that would otherwise not assemble spontaneously and what polymeric materials to choose to integrate motors into MEMS and other biohybrid devices. Finally, two applications that exploit the physical properties of microtubules are discussed, surface imaging by a swarm of microtubules and a self-assembled picoNewton force meter to probe receptor-ligand interactions.

  6. Efficient and Effective Change Principles in Active Videogames

    PubMed Central

    Fenner, Ashley A.; Howie, Erin K.; Feltz, Deborah L.; Gray, Cindy M.; Lu, Amy Shirong; Mueller, Florian “Floyd”; Simons, Monique; Barnett, Lisa M.

    2015-01-01

    Abstract Active videogames have the potential to enhance population levels of physical activity but have not been successful in achieving this aim to date. This article considers a range of principles that may be important to the design of effective and efficient active videogames from diverse discipline areas, including behavioral sciences (health behavior change, motor learning, and serious games), business production (marketing and sales), and technology engineering and design (human–computer interaction/ergonomics and flow). Both direct and indirect pathways to impact on population levels of habitual physical activity are proposed, along with the concept of a game use lifecycle. Examples of current active and sedentary electronic games are used to understand how such principles may be applied. Furthermore, limitations of the current usage of theoretical principles are discussed. A suggested list of principles for best practice in active videogame design is proposed along with suggested research ideas to inform practice to enhance physical activity. PMID:26181680

  7. Efficient and Effective Change Principles in Active Videogames.

    PubMed

    Straker, Leon M; Fenner, Ashley A; Howie, Erin K; Feltz, Deborah L; Gray, Cindy M; Lu, Amy Shirong; Mueller, Florian Floyd; Simons, Monique; Barnett, Lisa M

    2015-02-01

    Active videogames have the potential to enhance population levels of physical activity but have not been successful in achieving this aim to date. This article considers a range of principles that may be important to the design of effective and efficient active videogames from diverse discipline areas, including behavioral sciences (health behavior change, motor learning, and serious games), business production (marketing and sales), and technology engineering and design (human-computer interaction/ergonomics and flow). Both direct and indirect pathways to impact on population levels of habitual physical activity are proposed, along with the concept of a game use lifecycle. Examples of current active and sedentary electronic games are used to understand how such principles may be applied. Furthermore, limitations of the current usage of theoretical principles are discussed. A suggested list of principles for best practice in active videogame design is proposed along with suggested research ideas to inform practice to enhance physical activity.

  8. Advances on plant-pathogen interactions from molecular toward systems biology perspectives.

    PubMed

    Peyraud, Rémi; Dubiella, Ullrich; Barbacci, Adelin; Genin, Stéphane; Raffaele, Sylvain; Roby, Dominique

    2017-05-01

    In the past 2 decades, progress in molecular analyses of the plant immune system has revealed key elements of a complex response network. Current paradigms depict the interaction of pathogen-secreted molecules with host target molecules leading to the activation of multiple plant response pathways. Further research will be required to fully understand how these responses are integrated in space and time, and exploit this knowledge in agriculture. In this review, we highlight systems biology as a promising approach to reveal properties of molecular plant-pathogen interactions and predict the outcome of such interactions. We first illustrate a few key concepts in plant immunity with a network and systems biology perspective. Next, we present some basic principles of systems biology and show how they allow integrating multiomics data and predict cell phenotypes. We identify challenges for systems biology of plant-pathogen interactions, including the reconstruction of multiscale mechanistic models and the connection of host and pathogen models. Finally, we outline studies on resistance durability through the robustness of immune system networks, the identification of trade-offs between immunity and growth and in silico plant-pathogen co-evolution as exciting perspectives in the field. We conclude that the development of sophisticated models of plant diseases incorporating plant, pathogen and climate properties represent a major challenge for agriculture in the future. © 2016 The Authors. The Plant Journal published by John Wiley & Sons Ltd and Society for Experimental Biology.

  9. Using the Unified Modelling Language (UML) to guide the systemic description of biological processes and systems.

    PubMed

    Roux-Rouquié, Magali; Caritey, Nicolas; Gaubert, Laurent; Rosenthal-Sabroux, Camille

    2004-07-01

    One of the main issues in Systems Biology is to deal with semantic data integration. Previously, we examined the requirements for a reference conceptual model to guide semantic integration based on the systemic principles. In the present paper, we examine the usefulness of the Unified Modelling Language (UML) to describe and specify biological systems and processes. This makes unambiguous representations of biological systems, which would be suitable for translation into mathematical and computational formalisms, enabling analysis, simulation and prediction of these systems behaviours.

  10. Aerospace Medicine and Biology: A Continuing Bibliography. Supplement 483

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion.

  11. Eyes Wide Shut: the impact of dim-light vision on neural investment in marine teleosts.

    PubMed

    Iglesias, Teresa L; Dornburg, Alex; Warren, Dan L; Wainwright, Peter C; Schmitz, Lars; Economo, Evan P

    2018-05-28

    Understanding how organismal design evolves in response to environmental challenges is a central goal of evolutionary biology. In particular, assessing the extent to which environmental requirements drive general design features among distantly related groups is a major research question. The visual system is a critical sensory apparatus that evolves in response to changing light regimes. In vertebrates, the optic tectum is the primary visual processing centre of the brain and yet it is unclear how or whether this structure evolves while lineages adapt to changes in photic environment. On one hand, dim-light adaptation is associated with larger eyes and enhanced light-gathering power that could require larger information processing capacity. On the other hand, dim-light vision may evolve to maximize light sensitivity at the cost of acuity and colour sensitivity, which could require less processing power. Here, we use X-ray microtomography and phylogenetic comparative methods to examine the relationships between diel activity pattern, optic morphology, trophic guild and investment in the optic tectum across the largest radiation of vertebrates-teleost fishes. We find that despite driving the evolution of larger eyes, enhancement of the capacity for dim-light vision generally is accompanied by a decrease in investment in the optic tectum. These findings underscore the importance of considering diel activity patterns in comparative studies and demonstrate how vision plays a role in brain evolution, illuminating common design principles of the vertebrate visual system. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

  12. A Unifying Mathematical Framework for Genetic Robustness, Environmental Robustness, Network Robustness and their Trade-offs on Phenotype Robustness in Biological Networks. Part III: Synthetic Gene Networks in Synthetic Biology

    PubMed Central

    Chen, Bor-Sen; Lin, Ying-Po

    2013-01-01

    Robust stabilization and environmental disturbance attenuation are ubiquitous systematic properties that are observed in biological systems at many different levels. The underlying principles for robust stabilization and environmental disturbance attenuation are universal to both complex biological systems and sophisticated engineering systems. In many biological networks, network robustness should be large enough to confer: intrinsic robustness for tolerating intrinsic parameter fluctuations; genetic robustness for buffering genetic variations; and environmental robustness for resisting environmental disturbances. Network robustness is needed so phenotype stability of biological network can be maintained, guaranteeing phenotype robustness. Synthetic biology is foreseen to have important applications in biotechnology and medicine; it is expected to contribute significantly to a better understanding of functioning of complex biological systems. This paper presents a unifying mathematical framework for investigating the principles of both robust stabilization and environmental disturbance attenuation for synthetic gene networks in synthetic biology. Further, from the unifying mathematical framework, we found that the phenotype robustness criterion for synthetic gene networks is the following: if intrinsic robustness + genetic robustness + environmental robustness ≦ network robustness, then the phenotype robustness can be maintained in spite of intrinsic parameter fluctuations, genetic variations, and environmental disturbances. Therefore, the trade-offs between intrinsic robustness, genetic robustness, environmental robustness, and network robustness in synthetic biology can also be investigated through corresponding phenotype robustness criteria from the systematic point of view. Finally, a robust synthetic design that involves network evolution algorithms with desired behavior under intrinsic parameter fluctuations, genetic variations, and environmental disturbances, is also proposed, together with a simulation example. PMID:23515190

  13. A Unifying Mathematical Framework for Genetic Robustness, Environmental Robustness, Network Robustness and their Trade-offs on Phenotype Robustness in Biological Networks. Part III: Synthetic Gene Networks in Synthetic Biology.

    PubMed

    Chen, Bor-Sen; Lin, Ying-Po

    2013-01-01

    Robust stabilization and environmental disturbance attenuation are ubiquitous systematic properties that are observed in biological systems at many different levels. The underlying principles for robust stabilization and environmental disturbance attenuation are universal to both complex biological systems and sophisticated engineering systems. In many biological networks, network robustness should be large enough to confer: intrinsic robustness for tolerating intrinsic parameter fluctuations; genetic robustness for buffering genetic variations; and environmental robustness for resisting environmental disturbances. Network robustness is needed so phenotype stability of biological network can be maintained, guaranteeing phenotype robustness. Synthetic biology is foreseen to have important applications in biotechnology and medicine; it is expected to contribute significantly to a better understanding of functioning of complex biological systems. This paper presents a unifying mathematical framework for investigating the principles of both robust stabilization and environmental disturbance attenuation for synthetic gene networks in synthetic biology. Further, from the unifying mathematical framework, we found that the phenotype robustness criterion for synthetic gene networks is the following: if intrinsic robustness + genetic robustness + environmental robustness ≦ network robustness, then the phenotype robustness can be maintained in spite of intrinsic parameter fluctuations, genetic variations, and environmental disturbances. Therefore, the trade-offs between intrinsic robustness, genetic robustness, environmental robustness, and network robustness in synthetic biology can also be investigated through corresponding phenotype robustness criteria from the systematic point of view. Finally, a robust synthetic design that involves network evolution algorithms with desired behavior under intrinsic parameter fluctuations, genetic variations, and environmental disturbances, is also proposed, together with a simulation example.

  14. Physical Principles of Discrete Hierarchies Formation in Protein Macromolecules

    NASA Astrophysics Data System (ADS)

    Malyshko, E. V.; Tverdislov, V. A.

    2017-11-01

    A model for chiral periodicity with alternating chiral sense in hierarchies of protein and nucleic acid structures is proposed and substantiated. Regular alternation of the chirality sense is revealed in transitions from the lowest to higher levels of structural-functional organization in proteins where it is L-D-L-D. The stratification principle combines the ideas of biomacromolecules folding and molecular biological machines.

  15. Enzymes: principles and biotechnological applications

    PubMed Central

    Robinson, Peter K.

    2015-01-01

    Enzymes are biological catalysts (also known as biocatalysts) that speed up biochemical reactions in living organisms, and which can be extracted from cells and then used to catalyse a wide range of commercially important processes. This chapter covers the basic principles of enzymology, such as classification, structure, kinetics and inhibition, and also provides an overview of industrial applications. In addition, techniques for the purification of enzymes are discussed. PMID:26504249

  16. A biomimetic colorimetric logic gate system based on multi-functional peptide-mediated gold nanoparticle assembly

    NASA Astrophysics Data System (ADS)

    Li, Yong; Li, Wang; He, Kai-Yu; Li, Pei; Huang, Yan; Nie, Zhou; Yao, Shou-Zhuo

    2016-04-01

    In natural biological systems, proteins exploit various functional peptide motifs to exert target response and activity switch, providing a functional and logic basis for complex cellular activities. Building biomimetic peptide-based bio-logic systems is highly intriguing but remains relatively unexplored due to limited logic recognition elements and complex signal outputs. In this proof-of-principle work, we attempted to address these problems by utilizing multi-functional peptide probes and the peptide-mediated nanoparticle assembly system. Here, the rationally designed peptide probes function as the dual-target responsive element specifically responsive to metal ions and enzymes as well as the mediator regulating the assembly of gold nanoparticles (AuNPs). Taking advantage of Zn2+ ions and chymotrypsin as the model inputs of metal ions and enzymes, respectively, we constructed the peptide logic system computed by the multi-functional peptide probes and outputted by the readable colour change of AuNPs. In this way, the representative binary basic logic gates (AND, OR, INHIBIT, NAND, IMPLICATION) have been achieved by delicately coding the peptide sequence, demonstrating the versatility of our logic system. Additionally, we demonstrated that the three-input combinational logic gate (INHIBIT-OR) could also be successfully integrated and applied as a multi-tasking biosensor for colorimetric detection of dual targets. This nanoparticle-based peptide logic system presents a valid strategy to illustrate peptide information processing and provides a practical platform for executing peptide computing or peptide-related multiplexing sensing, implying that the controllable nanomaterial assembly is a promising and potent methodology for the advancement of biomimetic bio-logic computation.In natural biological systems, proteins exploit various functional peptide motifs to exert target response and activity switch, providing a functional and logic basis for complex cellular activities. Building biomimetic peptide-based bio-logic systems is highly intriguing but remains relatively unexplored due to limited logic recognition elements and complex signal outputs. In this proof-of-principle work, we attempted to address these problems by utilizing multi-functional peptide probes and the peptide-mediated nanoparticle assembly system. Here, the rationally designed peptide probes function as the dual-target responsive element specifically responsive to metal ions and enzymes as well as the mediator regulating the assembly of gold nanoparticles (AuNPs). Taking advantage of Zn2+ ions and chymotrypsin as the model inputs of metal ions and enzymes, respectively, we constructed the peptide logic system computed by the multi-functional peptide probes and outputted by the readable colour change of AuNPs. In this way, the representative binary basic logic gates (AND, OR, INHIBIT, NAND, IMPLICATION) have been achieved by delicately coding the peptide sequence, demonstrating the versatility of our logic system. Additionally, we demonstrated that the three-input combinational logic gate (INHIBIT-OR) could also be successfully integrated and applied as a multi-tasking biosensor for colorimetric detection of dual targets. This nanoparticle-based peptide logic system presents a valid strategy to illustrate peptide information processing and provides a practical platform for executing peptide computing or peptide-related multiplexing sensing, implying that the controllable nanomaterial assembly is a promising and potent methodology for the advancement of biomimetic bio-logic computation. Electronic supplementary information (ESI) available: Additional figures (Tables S1-S3 and Fig. S1-S6). See DOI: 10.1039/c6nr01072e

  17. Life detection systems.

    NASA Technical Reports Server (NTRS)

    Mitz, M. A.

    1972-01-01

    Some promising newer approaches for detecting microorganisms are discussed, giving particular attention to the integration of different methods into a single instrument. Life detection methods may be divided into biological, chemical, and cytological methods. Biological methods are based on the biological properties of assimilation, metabolism, and growth. Devices for the detection of organic materials are considered, taking into account an instrument which volatilizes, separates, and analyzes a sample sequentially. Other instrumental systems described make use of a microscope and the cytochemical staining principle.

  18. Defining viral species: making taxonomy useful.

    PubMed

    Peterson, A Townsend

    2014-07-23

    Virus taxonomy at present is best characterized as a categorization of convenience, without a firm basis in the principles of evolutionary biology. Specifically, virus species definitions appear to depend more on tradition and popular opinion among virologists than on firm, quantitative biological evidence. I suggest a series of changes to underlying species concepts that would shift the field from one that simply files viruses away in taxonomic boxes to one that can learn important biological lessons from its taxonomy.

  19. Analyzing Defects in the "Caenorhabditis Elegans" Nervous System Using Organismal and Cell Biological Approaches

    ERIC Educational Resources Information Center

    Guziewicz, Megan; Vitullo, Toni; Simmons, Bethany; Kohn, Rebecca Eustance

    2002-01-01

    The goal of this laboratory exercise is to increase student understanding of the impact of nervous system function at both the organismal and cellular levels. This inquiry-based exercise is designed for an undergraduate course examining principles of cell biology. After observing the movement of "Caenorhabditis elegans" with defects in their…

  20. Aliens in the Classroom: Fantastical Creatures as Tools in Teaching Biology

    ERIC Educational Resources Information Center

    Cruz, Ronald Allan L.

    2013-01-01

    Creatures from science fiction and fantasy can be used to illustrate key concepts and principles in biology. This article describes a project for a university-level general zoology course wherein the students classify, down to at least the phylum level, "animals" from the Alien Species Wiki (2013). This is an online database of creatures from…

  1. Foundational Concepts and Underlying Theories for Majors in "Biochemistry and Molecular Biology"

    ERIC Educational Resources Information Center

    Tansey, John T.; Baird, Teaster, Jr.; Cox, Michael M.; Fox, Kristin M.; Knight, Jennifer; Sears, Duane; Bell, Ellis

    2013-01-01

    Over the past two years, through an NSF RCN UBE grant, the ASBMB has held regional workshops for faculty members and science educators from around the country that focused on identifying: 1) core principles of biochemistry and molecular biology, 2) essential concepts and underlying theories from physics, chemistry, and mathematics, and 3)…

  2. Animated Cell Biology: A Quick and Easy Method for Making Effective, High-Quality Teaching Animations

    ERIC Educational Resources Information Center

    O'Day, Danton H.

    2006-01-01

    There is accumulating evidence that animations aid learning of dynamic concepts in cell biology. However, existing animation packages are expensive and difficult to learn, and the subsequent production of even short animations can take weeks to months. Here I outline the principles and sequence of steps for producing high-quality PowerPoint…

  3. Physics for Medicine and Biology: Determining Body Fat Content

    NASA Astrophysics Data System (ADS)

    Aaron, Ronald; Altman, Albert

    2011-04-01

    Hydrostatic weighing is a technique for determining body fat content that is based on Archimedes principle and varied applications of the ideal gas law. We use this procedure as an example of the types of physics material which should be presented in an introductory course for students that are interested in careers in biology and medicine.

  4. Testing and Evaluating Student Success with Laboratory Blocks, A Resource Book for Teachers.

    ERIC Educational Resources Information Center

    Lee, Addison E.

    Guidelines are given for the preparation of test items and tests for BSCS (Biological Sciences Curriculum Study) biology, including examples of items testing four major kinds of abilities: ability to repeat or use information and meanings, ability to apply principles, ability to apply intellectual skills crucial to the understanding of biological…

  5. Demonstration of the Principles of Restriction Endonuclease Cleavage Reactions Using Thermostable Bfl I from "Anoxybacillus Flavithermus"

    ERIC Educational Resources Information Center

    Sharma, Prince; D'Souza, David R.; Bhandari, Deepali; Parashar, Vijay; Capalash, Neena

    2003-01-01

    Restriction enzymes are basic tools in recombinant DNA technology. To shape the molecular biology experiments, the students must know how to work with these molecular scissors. Here, we describe an integrated set of experiments, introduced in the "Advances in Molecular Biology and Biotechnology" postgraduate course, which covers the important…

  6. Unweaving Misconceptions: Guided Learning, Simulations, and Misconceptions in Learning Principles of Natural Selection

    ERIC Educational Resources Information Center

    Weeks, Brian E.

    2013-01-01

    College students often come to the study of evolutionary biology with many misconceptions of how the processes of natural selection and speciation occur. How to relinquish these misconceptions with learners is a question that many educators face in introductory biology courses. Constructivism as a theoretical framework has become an accepted and…

  7. An Introductory Biology Lab that Uses Enzyme Histochemistry to Teach Students about Skeletal Muscle Fiber Types

    ERIC Educational Resources Information Center

    Sweeney, Lauren J.; Brodfuehrer, Peter D.; Raughley, Beth L.

    2004-01-01

    One important goal of introductory biology laboratory experiences is to engage students directly in all steps in the process of scientific discovery. Even when laboratory experiences are built on principles discussed in the classroom, students often do not adequately apply this background to interpretation of results they obtain in lab. This…

  8. Understanding phylogenies in biology: the influence of a Gestalt Perceptual Principle.

    PubMed

    Novick, Laura R; Catley, Kefyn M

    2007-12-01

    Cladograms, hierarchical diagrams depicting evolutionary histories among (groups of) species, are commonly drawn in 2 informationally equivalent formats--tree and ladder. The authors hypothesize that these formats are not computationally equivalent because the Gestalt principle of good continuation obscures the hierarchical structure of ladders. Experimental results confirmed that university students (N = 44) prefer to subdivide ladders in accordance with good continuation rather than with the underlying hierarchical structure. Two subsequent experiments (N = 164) investigated cladogram understanding by examining students' ability to translate between formats (e.g., from tree to ladder). As predicted, students had greater difficulty understanding ladders than trees. This effect was larger for students with weaker backgrounds in biology. These results have important implications for evolution education reform.

  9. Biological attachment devices: exploring nature's diversity for biomimetics.

    PubMed

    Gorb, Stanislav N

    2008-05-13

    Many species of animals and plants are supplied with diverse attachment devices, in which morphology depends on the species biology and the particular function in which the attachment device is involved. Many functional solutions have evolved independently in different lineages of animals and plants. Since the diversity of such biological structures is huge, there is a need for their classification. This paper, based on the original and literature data, proposes ordering of biological attachment systems according to several principles: (i) fundamental physical mechanism, according to which the system operates, (ii) biological function of the attachment device, and (iii) duration of the contact. Finally, we show a biomimetic potential of studies on biological attachment devices.

  10. Hierarchical structure of biological systems

    PubMed Central

    Alcocer-Cuarón, Carlos; Rivera, Ana L; Castaño, Victor M

    2014-01-01

    A general theory of biological systems, based on few fundamental propositions, allows a generalization of both Wierner and Berthalanffy approaches to theoretical biology. Here, a biological system is defined as a set of self-organized, differentiated elements that interact pair-wise through various networks and media, isolated from other sets by boundaries. Their relation to other systems can be described as a closed loop in a steady-state, which leads to a hierarchical structure and functioning of the biological system. Our thermodynamical approach of hierarchical character can be applied to biological systems of varying sizes through some general principles, based on the exchange of energy information and/or mass from and within the systems. PMID:24145961

  11. Hierarchical structure of biological systems: a bioengineering approach.

    PubMed

    Alcocer-Cuarón, Carlos; Rivera, Ana L; Castaño, Victor M

    2014-01-01

    A general theory of biological systems, based on few fundamental propositions, allows a generalization of both Wierner and Berthalanffy approaches to theoretical biology. Here, a biological system is defined as a set of self-organized, differentiated elements that interact pair-wise through various networks and media, isolated from other sets by boundaries. Their relation to other systems can be described as a closed loop in a steady-state, which leads to a hierarchical structure and functioning of the biological system. Our thermodynamical approach of hierarchical character can be applied to biological systems of varying sizes through some general principles, based on the exchange of energy information and/or mass from and within the systems.

  12. Using evolutionary computations to understand the design and evolution of gene and cell regulatory networks.

    PubMed

    Spirov, Alexander; Holloway, David

    2013-07-15

    This paper surveys modeling approaches for studying the evolution of gene regulatory networks (GRNs). Modeling of the design or 'wiring' of GRNs has become increasingly common in developmental and medical biology, as a means of quantifying gene-gene interactions, the response to perturbations, and the overall dynamic motifs of networks. Drawing from developments in GRN 'design' modeling, a number of groups are now using simulations to study how GRNs evolve, both for comparative genomics and to uncover general principles of evolutionary processes. Such work can generally be termed evolution in silico. Complementary to these biologically-focused approaches, a now well-established field of computer science is Evolutionary Computations (ECs), in which highly efficient optimization techniques are inspired from evolutionary principles. In surveying biological simulation approaches, we discuss the considerations that must be taken with respect to: (a) the precision and completeness of the data (e.g. are the simulations for very close matches to anatomical data, or are they for more general exploration of evolutionary principles); (b) the level of detail to model (we proceed from 'coarse-grained' evolution of simple gene-gene interactions to 'fine-grained' evolution at the DNA sequence level); (c) to what degree is it important to include the genome's cellular context; and (d) the efficiency of computation. With respect to the latter, we argue that developments in computer science EC offer the means to perform more complete simulation searches, and will lead to more comprehensive biological predictions. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Systematic, spatial imaging of large multimolecular assemblies and the emerging principles of supramolecular order in biological systems

    PubMed Central

    Schubert, Walter

    2013-01-01

    Understanding biological systems at the level of their relational (emergent) molecular properties in functional protein networks relies on imaging methods, able to spatially resolve a tissue or a cell as a giant, non-random, topologically defined collection of interacting supermolecules executing myriads of subcellular mechanisms. Here, the development and findings of parameter-unlimited functional super-resolution microscopy are described—a technology based on the fluorescence imaging cycler (IC) principle capable of co-mapping thousands of distinct biomolecular assemblies at high spatial resolution and differentiation (<40 nm distances). It is shown that the subcellular and transcellular features of such supermolecules can be described at the compositional and constitutional levels; that the spatial connection, relational stoichiometry, and topology of supermolecules generate hitherto unrecognized functional self-segmentation of biological tissues; that hierarchical features, common to thousands of simultaneously imaged supermolecules, can be identified; and how the resulting supramolecular order relates to spatial coding of cellular functionalities in biological systems. A large body of observations with IC molecular systems microscopy collected over 20 years have disclosed principles governed by a law of supramolecular segregation of cellular functionalities. This pervades phenomena, such as exceptional orderliness, functional selectivity, combinatorial and spatial periodicity, and hierarchical organization of large molecular systems, across all species investigated so far. This insight is based on the high degree of specificity, selectivity, and sensitivity of molecular recognition processes for fluorescence imaging beyond the spectral resolution limit, using probe libraries controlled by ICs. © 2013 The Authors. Journal of Molecular Recognition published by John Wiley & Sons, Ltd. PMID:24375580

  14. Quantitative Detection and Biological Propagation of Scrapie Seeding Activity In Vitro Facilitate Use of Prions as Model Pathogens for Disinfection

    PubMed Central

    Pritzkow, Sandra; Wagenführ, Katja; Daus, Martin L.; Boerner, Susann; Lemmer, Karin; Thomzig, Achim; Mielke, Martin; Beekes, Michael

    2011-01-01

    Prions are pathogens with an unusually high tolerance to inactivation and constitute a complex challenge to the re-processing of surgical instruments. On the other hand, however, they provide an informative paradigm which has been exploited successfully for the development of novel broad-range disinfectants simultaneously active also against bacteria, viruses and fungi. Here we report on the development of a methodological platform that further facilitates the use of scrapie prions as model pathogens for disinfection. We used specifically adapted serial protein misfolding cyclic amplification (PMCA) for the quantitative detection, on steel wires providing model carriers for decontamination, of 263K scrapie seeding activity converting normal protease-sensitive into abnormal protease-resistant prion protein. Reference steel wires carrying defined amounts of scrapie infectivity were used for assay calibration, while scrapie-contaminated test steel wires were subjected to fifteen different procedures for disinfection that yielded scrapie titre reductions of ≤101- to ≥105.5-fold. As confirmed by titration in hamsters the residual scrapie infectivity on test wires could be reliably deduced for all examined disinfection procedures, from our quantitative seeding activity assay. Furthermore, we found that scrapie seeding activity present in 263K hamster brain homogenate or multiplied by PMCA of scrapie-contaminated steel wires both triggered accumulation of protease-resistant prion protein and was further propagated in a novel cell assay for 263K scrapie prions, i.e., cerebral glial cell cultures from hamsters. The findings from our PMCA- and glial cell culture assays revealed scrapie seeding activity as a biochemically and biologically replicative principle in vitro, with the former being quantitatively linked to prion infectivity detected on steel wires in vivo. When combined, our in vitro assays provide an alternative to titrations of biological scrapie infectivity in animals that substantially facilitates the use of prions as potentially highly indicative test agents in the search for novel broad-range disinfectants. PMID:21647368

  15. Infusing Bioethics into Biology and Microbiology Courses and Curricula: A Vertical Approach

    PubMed Central

    Jagger, Kathleen S.; Furlong, Jack

    2014-01-01

    With the rise of biomedicine and biotechnology, there has been a corresponding growth in the need for better understanding of consequent ethical questions. Increasingly, biologists are being asked not only to offer technical clarifications but also to venture ethical opinions, for which most feel poorly equipped. This expectation puts pressure on biology instructors at the university level to provide biology majors the skills and experience to discuss with some confidence and competence bioethical issues which may arise in either the workplace or through public discourse in everyday contexts. Many fine curricular resources about bioethics are available for varied pedagogical purposes, but few target undergraduate biology or microbiology student audiences. When it occurs in the context of a course, bioethics instruction often is taught by non-biologists outside standard biology curricula. We propose that biologists should strive to “infuse” bioethical thinking into their courses and major curricula but not in such a way as merely to point at ethical problems, treating them at a surface level. We suggest what we call “vertical infusion”: taking one bioethical issue per course and integrating this issue within the context of a relevant biological topic, challenging students to push their thinking beyond their initial intuitions toward underlying scientific and ethical principles. While the vertical approach lacks widespread coverage of ethical issues throughout a single course, it has the advantage of taking the bioethical dimension seriously and in intimate relation to contemporary discoveries in biology and to the biological principles, processes, or procedures that occasioned the ethical quandaries in the first place. PMID:25574281

  16. [The optimization of restoration approaches of advanced hand activity using the sensorial glove and the mCIMT method].

    PubMed

    Mozheiko, E Yu; Prokopenko, S V; Alekseevich, G V

    To reason the choice of methods of restoration of advanced hand activity depending on severity of motor disturbance in the top extremity. Eighty-eight patients were randomized into 3 groups: 1) the mCIMT group, 2) the 'touch glove' group, 3) the control group. For assessment of physical activity of the top extremity Fugl-Meyer Assessment Upper Extremity, Nine-Hole Peg Test, Motor Assessment Scale were used. Assessment of non-use phenomenon was carried out with the Motor Activity Log scale. At a stage of severe motor dysfunction, there was a restoration of proximal departments of a hand in all groups, neither method was superior to the other. In case of moderate severity of motor deficiency of the upper extremity the most effective was the method based on the principle of biological feedback - 'a touch glove'. In the group with mild severity of motor dysfunction, the best recovery was achieved in the mCIMT group.

  17. Active site structure and catalytic mechanism of phosphodiesterase for degradation of intracellular second messengers

    NASA Astrophysics Data System (ADS)

    Zhan, Chang-Guo

    2002-03-01

    Phosphodiesterases are clinical targets for a variety of biological disorders, because this superfamily of enzymes regulate intracellular concentration of cyclic nucleotides that serve as the second messengers playing a critical role in a variety of physiological processes. Understanding structure and mechanism of a phosphodiesterase will provide a solid basis for rational design of the more efficient therapeutics. Although a three-dimensional X-ray crystal structure of the catalytic domain of human phosphodiesterase 4B2B was recently reported, it was uncertain whether a critical bridging ligand in the active site is a water molecule or a hydroxide ion. The identity of this bridging ligand has been determined by performing first-principles quantum chemical calculations on models of the active site. All the results obtained indicate that this critical bridging ligand in the active site of the reported X-ray crystal structure is a hydroxide ion, rather than a water molecule, expected to serve as the nucleophile to initialize the catalytic degradation of the intracellular second messengers.

  18. SH2 Domain-Based FRET Biosensor for Measuring BCR-ABL Activity in Living CML Cells.

    PubMed

    Fujioka, Mari; Asano, Yumi; Nakada, Shigeyuki; Ohba, Yusuke

    2017-01-01

    Fluorescent proteins (FPs) displaying distinct spectra have shed their light on a wide range of biological functions. Moreover, sophisticated biosensors engineered to contain single or multiple FPs, including Förster resonance energy transfer (FRET)-based biosensors, spatiotemporally reveal the molecular mechanisms underlying a variety of pathophysiological processes. However, their usefulness for applied life sciences has yet to be fully explored. Recently, our research group has begun to expand the potential of FPs from basic biological research to the clinic. Here, we describe a method to evaluate the responsiveness of leukemia cells from patients to tyrosine kinase inhibitors using a biosensor based on FP technology and the principle of FRET. Upon phosphorylation of the tyrosine residue of the biosensor, binding of the SH2 domain to phosphotyrosine induces conformational change of the biosensor and brings the donor and acceptor FPs into close proximity. Therefore, kinase activity and response to kinase inhibitors can be monitored by an increase and a decrease in FRET efficiency, respectively. As in basic research, this biosensor resolves hitherto arduous tasks and may provide innovative technological advances in clinical laboratory examinations. State-of-the-art detection devices that enable such innovation are also introduced.

  19. Green extraction of natural products: concept and principles.

    PubMed

    Chemat, Farid; Vian, Maryline Abert; Cravotto, Giancarlo

    2012-01-01

    The design of green and sustainable extraction methods of natural products is currently a hot research topic in the multidisciplinary area of applied chemistry, biology and technology. Herein we aimed to introduce the six principles of green-extraction, describing a multifaceted strategy to apply this concept at research and industrial level. The mainstay of this working protocol are new and innovative technologies, process intensification, agro-solvents and energy saving. The concept, principles and examples of green extraction here discussed, offer an updated glimpse of the huge technological effort that is being made and the diverse applications that are being developed.

  20. Twenty-five years of maximum-entropy principle

    NASA Astrophysics Data System (ADS)

    Kapur, J. N.

    1983-04-01

    The strengths and weaknesses of the maximum entropy principle (MEP) are examined and some challenging problems that remain outstanding at the end of the first quarter century of the principle are discussed. The original formalism of the MEP is presented and its relationship to statistical mechanics is set forth. The use of MEP for characterizing statistical distributions, in statistical inference, nonlinear spectral analysis, transportation models, population density models, models for brand-switching in marketing and vote-switching in elections is discussed. Its application to finance, insurance, image reconstruction, pattern recognition, operations research and engineering, biology and medicine, and nonparametric density estimation is considered.

  1. Fermi paradox and alternative strategies for SETI programs - The anthropic principle and the search for close solar analogs

    NASA Astrophysics Data System (ADS)

    Fracassini, Massimo; Pasinetti Fracassini, Laura E.; Pasinetti, Antonio L.

    1988-07-01

    The Anthropic Principle, a new trend of modern cosmology, claims that the origin of life and the development of intelligent beings on the Earth is the result of highly selective biological processes, strictly tuned in the fundamental physical characteristics of the Universe. This principle could account for the failure of some programs of search for extraterrestrial intelligences (SETI) and suggests the search for strict solar analogs as a primary target for SETI strategies. In this connection, the authors have selected 22 solar analogs and discussed their choice.

  2. The neural circuits for arithmetic principles.

    PubMed

    Liu, Jie; Zhang, Han; Chen, Chuansheng; Chen, Hui; Cui, Jiaxin; Zhou, Xinlin

    2017-02-15

    Arithmetic principles are the regularities underlying arithmetic computation. Little is known about how the brain supports the processing of arithmetic principles. The current fMRI study examined neural activation and functional connectivity during the processing of verbalized arithmetic principles, as compared to numerical computation and general language processing. As expected, arithmetic principles elicited stronger activation in bilateral horizontal intraparietal sulcus and right supramarginal gyrus than did language processing, and stronger activation in left middle temporal lobe and left orbital part of inferior frontal gyrus than did computation. In contrast, computation elicited greater activation in bilateral horizontal intraparietal sulcus (extending to posterior superior parietal lobule) than did either arithmetic principles or language processing. Functional connectivity analysis with the psychophysiological interaction approach (PPI) showed that left temporal-parietal (MTG-HIPS) connectivity was stronger during the processing of arithmetic principle and language than during computation, whereas parietal-occipital connectivities were stronger during computation than during the processing of arithmetic principles and language. Additionally, the left fronto-parietal (orbital IFG-HIPS) connectivity was stronger during the processing of arithmetic principles than during computation. The results suggest that verbalized arithmetic principles engage a neural network that overlaps but is distinct from the networks for computation and language processing. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Cosmic evolution: the context for astrobiology and its cultural implications

    NASA Astrophysics Data System (ADS)

    Dick, Steven J.

    2012-10-01

    Astrobiology must be seen in the context of cosmic evolution, the 13.7 billion-year master narrative of the universe. The idea of an evolving universe dates back only to the 19th century, and became a guiding principle for astronomical research only in the second half of the 20th century. The modern synthesis in evolutionary biology hastened the acceptance of the idea in its cosmic setting, as did the confirmation of the Big Bang theory for the origin of the universe. NASA programmes such as Origins incorporated it as a guiding principle. Cosmic evolution encompasses physical, biological and cultural evolution, and may result in a physical, biological or postbiological universe, each with its own implications for long-term human destiny, and each imbuing the meaning of life with different values. It has the status of an increasingly accepted worldview that is beginning to have a profound effect not only in science but also in religion and philosophy.

  4. Affinity monolith chromatography: A review of general principles and applications.

    PubMed

    Li, Zhao; Rodriguez, Elliott; Azaria, Shiden; Pekarek, Allegra; Hage, David S

    2017-11-01

    Affinity monolith chromatography, or AMC, is a liquid chromatographic method in which the support is a monolith and the stationary phase is a biological-binding agent or related mimic. AMC has become popular for the isolation of biochemicals, for the measurement of various analytes, and for studying biological interactions. This review will examine the principles and applications of AMC. The materials that have been used to prepare AMC columns will be discussed, which have included various organic polymers, silica, agarose, and cryogels. Immobilization schemes that have been used in AMC will also be considered. Various binding agents and applications that have been reported for AMC will then be described. These applications will include the use of AMC for bioaffinity chromatography, immunoaffinity chromatography, dye-ligand affinity chromatography, and immobilized metal-ion affinity chromatography. The use of AMC with chiral stationary phases and as a tool to characterize biological interactions will also be examined. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. A systems approach to physiologic evolution: From micelles to consciousness.

    PubMed

    Torday, John S; Miller, William B

    2018-01-01

    A systems approach to evolutionary biology offers the promise of an improved understanding of the fundamental principles of life through the effective integration of many biologic disciplines. It is presented that any critical integrative approach to evolutionary development involves a paradigmatic shift in perspective, more than just the engagement of a large number of disciplines. Critical to this differing viewpoint is the recognition that all biological processes originate from the unicellular state and remain permanently anchored to that phase throughout evolutionary development despite their macroscopic appearances. Multicellular eukaryotic development can, therefore, be viewed as a series of connected responses to epiphenomena that proceeds from that base in continuous iterative maintenance of collective cellular homeostatic equipoise juxtaposed against an ever-changing and challenging environment. By following this trajectory of multicellular eukaryotic evolution from within unicellular First Principles of Physiology forward, the mechanistic nature of complex physiology can be identified through a step-wise analysis of a continuous arc of vertebrate evolution based upon serial exaptations. © 2017 Wiley Periodicals, Inc.

  6. An introductory biology lab that uses enzyme histochemistry to teach students about skeletal muscle fiber types.

    PubMed

    Sweeney, Lauren J; Brodfuehrer, Peter D; Raughley, Beth L

    2004-12-01

    One important goal of introductory biology laboratory experiences is to engage students directly in all steps in the process of scientific discovery. Even when laboratory experiences are built on principles discussed in the classroom, students often do not adequately apply this background to interpretation of results they obtain in lab. This disconnect has been described at the level of medical education (4), so it should not be surprising that educators have struggled with this same phenomenon at the undergraduate level. We describe a new introductory biology lab that challenges students to make these connections. The lab utilizes enzyme histochemistry and morphological observations to draw conclusions about the composition of functionally different types of muscle fibers present in skeletal muscle. We report that students were not only successful at making these observations on a specific skeletal muscle, the gastrocnemius of the frog Rana pipiens, but that they were able to connect their results to the principles of fiber type differences that exist in skeletal muscles in all vertebrates.

  7. Conway's "Game of Life" and the Epigenetic Principle.

    PubMed

    Caballero, Lorena; Hodge, Bob; Hernandez, Sergio

    2016-01-01

    Cellular automatons and computer simulation games are widely used as heuristic devices in biology, to explore implications and consequences of specific theories. Conway's Game of Life has been widely used for this purpose. This game was designed to explore the evolution of ecological communities. We apply it to other biological processes, including symbiopoiesis. We show that Conway's organization of rules reflects the epigenetic principle, that genetic action and developmental processes are inseparable dimensions of a single biological system, analogous to the integration processes in symbiopoiesis. We look for similarities and differences between two epigenetic models, by Turing and Edelman, as they are realized in Game of Life objects. We show the value of computer simulations to experiment with and propose generalizations of broader scope with novel testable predictions. We use the game to explore issues in symbiopoiesis and evo-devo, where we explore a fractal hypothesis: that self-similarity exists at different levels (cells, organisms, ecological communities) as a result of homologous interactions of two as processes modeled in the Game of Life.

  8. Frontiers, Opportunities, and Challenges in Biochemical and Chemical Catalysis of CO2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Appel, Aaron M.; Bercaw, John E.; Bocarsly, Andrew B.

    2013-08-14

    Our central premise is that catalytic scientists can learn by studying how these important metabolic processes occur in nature. Complementarily, biochemists can learn by studying how catalytic scientists view these same chemical transformations promoted by synthetic catalysts. From these studies, hypotheses can be developed and tested through manipulation of enzyme structure and by synthesizing simple molecular catalysts to incorporate different structural features of the enzymes. It is hoped that these studies will lead to new and useful concepts in catalyst design for fuel production and utilization. This paper describes the results of a workshop held to explore these concepts inmore » regard to the development of new and more efficient catalytic processes for the conversion of CO2 to a variety of carbon-based fuels. The organization of this overview/review is as follows: 1) The first section briefly explores how interactions between the catalysis and biological communities have been fruitful in developing new catalysts for the reduction of protons to hydrogen, the simplest fuel generation reaction. 2) The second section assesses the state of the art in both biological and chemical reduction of CO2 by two electrons to form either carbon monoxide (CO) or formate (HCOO-). It also attempts to identify common principles between biological and synthetic catalysts and productive areas for future research. 3) The third section explores both biological and chemical processes that result in the reduction of CO2 beyond the level of CO and formate, again seeking to identify common principles and productive areas of future research. 4) The fourth section explores the formation of carbon-carbon bonds in biological and chemical systems in the same vein as the other sections. 5) A fifth section addresses the role of non-redox reactions of CO2 in biological systems and their role in carbon metabolism, with a parallel discussion of chemical systems. 6) In section 6, the topics of electrode modification, photochemical systems, and tandem catalysis are briefly discussed. These areas may be important for developing practical systems for CO2 reduction, and they share the common theme of coupling chemical reactions. 7) Section 7 describes some of the crosscutting activities that are critical for advancing the science underpinning catalyst development. 8) The last section attempts to summarize common issues in biological and chemical catalysis and to identify challenges that must be addressed to achieve practical catalysts that are suitable for the reduction of CO2 to fuels.« less

  9. [Fuzzy mathematic quantitative law of composing principle in the study of traditional Chinese medicine].

    PubMed

    Liu, Ming; Gao, Yue; Xiao, Rui; Zhang, Bo-li

    2009-01-01

    This study is to analyze microcosmic significance of Chinese medicine composing principle "principal, assistant, complement and mediating guide" and it's fuzzy mathematic quantitative law. According to molecular biology and maximal membership principle, fuzzy subset and membership functions were proposed. Using in vivo experiment on the effects of SiWu Decoction and its ingredients on mice with radiation-induced blood deficiency, it is concluded that DiHuang and DangGui belonged to the principal and assistant subset, BaiShao belonged to the contrary complement subset, ChuanXiong belonged to the mediating guide subset by maximal membership principle. It is discussed that traditional Chinese medicine will be consummate medical science when its theory can be described by mathematic language.

  10. Antibacterial and Anti-inflammatory Activities of Ppc-1, Active Principle of the Cellular Slime Mold Polysphondylium pseudo-candidum.

    PubMed

    Azelmat, Jabrane; Fiorito, Serena; Genovese, Salvatore; Epifano, Francesco; Grenier, Daniel

    2015-01-01

    The diisopentenyloxy quinolobactin derivative 3-methylbut-2-enyl-4-methoxy-8-[(3-methylbut-2-enyl)oxy] quinoline-2-carboxylate, also named as Ppc-1, has been initially isolated from the fruiting bodies of the cellular slime mold Polysphondylium pseudo-candidum. Given that few data are available in the literature concerning the biological properties of this compound, this study was undertaken to evaluate its antibacterial and anti-inflammatory properties. Ppc-1 exerted antibacterial activity on the Gram negative periodontopathogen Porphyromonas gingivalis, while it had no such effect on the other bacterial species tested. The antibacterial activity of Ppc-1 appeared to result from its ability to permeate the cell membrane. Using the U937-3xκB-LUC human monocytic cell line, Ppc-1 was found to dose-dependently inhibit the lipopolysaccharide-induced NF-κB activation, a signaling pathway that has been associated with inflammatory mediator secretion. In conclusion, Ppc-1, by exhibiting a dual mode of action including antibacterial and anti-inflammatory activities, may represent a promising targeted therapeutic agent for periodontal diseases.

  11. [Principles of management in biological infections].

    PubMed

    Płusa, Tadeusz

    2012-11-01

    The effectiveness of the management in respiratory infection is depending on the nature of the biological pathogen and the immune status of the patient. For this reason, providing assistance to victims the organ function support, similarly as defining the pathogen and targeted antibiotic therapy should be applied. Available diagnostic tests provide rapid ability to identify the pathogen and antibiotics are able to control infection. Lack of efficacy of treatment may indicate the diversity of the pathogen than previously known and raises suspicion of biological warfare pathogen.

  12. Synthetic biology: exploring and exploiting genetic modularity through the design of novel biological networks.

    PubMed

    Agapakis, Christina M; Silver, Pamela A

    2009-07-01

    Synthetic biology has been used to describe many biological endeavors over the past thirty years--from designing enzymes and in vitro systems, to manipulating existing metabolisms and gene expression, to creating entirely synthetic replicating life forms. What separates the current incarnation of synthetic biology from the recombinant DNA technology or metabolic engineering of the past is an emphasis on principles from engineering such as modularity, standardization, and rigorously predictive models. As such, synthetic biology represents a new paradigm for learning about and using biological molecules and data, with applications in basic science, biotechnology, and medicine. This review covers the canonical examples as well as some recent advances in synthetic biology in terms of what we know and what we can learn about the networks underlying biology, and how this endeavor may shape our understanding of living systems.

  13. Future perspectives of personalized medicine in traditional Chinese medicine: a systems biology approach.

    PubMed

    Zhang, Aihua; Sun, Hui; Wang, Ping; Han, Ying; Wang, Xijun

    2012-01-01

    Deconstruction of molecular pathways and advances in enabling technology platforms have opened new horizons for disease management, exploring therapeutic solutions to each individual patient beyond the one-size fits all practice. Application of personalized medicine paradigms aims to achieve the right diagnosis and right treatment for the right patient at the right time at the right cost. With the potential to transform medical practice across global communities, personalized medicine is emerging as the flagship of modern medicine. In recent years, the health care paradigm has shifted from a focus on diseases to a major hot of personalized traditional Chinese medicine (TCM) with holistic approach. TCM focuses on health maintenance, emphasizes on enhancing the body's resistance to diseases and especially showes great advantages in early intervention, personalized and combination therapies, etc. Systems biology, a new science of the 21st century, becomes practically available and resembles TCM in many aspects such as study method and design, and is current key component technologies that serves as the major driving force for translation of the personalized medicine revolution of TCM principles into practice, will advance personalized therapy principles into healthcare management tools for individuals and populations. Such system approach concepts are transforming principles of TCM to modern therapeutic approaches, enable a predictive and preventive medicine and will lead to personalized medicine. To realise the full potential of personalized TCM, we describe the current status of principles and practice of TCM integrated with systems biology platform. Some characteristic examples are presented to highlight the application of this platform to personalized TCM research and development as well as some of the necessary milestones for moving TCM into mainstream health care. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Synthetic biology and the ethics of knowledge

    PubMed Central

    Douglas, Thomas; Savulescu, Julian

    2011-01-01

    Synthetic biologists aim to generate biological organisms according to rational design principles. Their work may have many beneficial applications, but it also raises potentially serious ethical concerns. In this article, we consider what attention the discipline demands from bioethicists. We argue that the most important issue for ethicists to examine is the risk that knowledge from synthetic biology will be misused, for example, in biological terrorism or warfare. To adequately address this concern, bioethics will need to broaden its scope, contemplating not just the means by which scientific knowledge is produced, but also what kinds of knowledge should be sought and disseminated. PMID:20935316

  15. The Role of Noise in Brain Function

    NASA Astrophysics Data System (ADS)

    Roy, S.; Llinás, R.

    2012-12-01

    Noise plays a fundamental role in all living organisms from the earliest prokaryotes to advanced mammalian forms, such as ourselves. In the context of living organisms, the term 'noise' usually refers to the variance amongst measurements obtained from repeated identical experimental conditions, or from output signals from these systems. It is noteworthy that both these conditions are universally characterized by the presence of background fluctuations. In non-biological systems, such as electronics or in communications sciences, where the aim is to send error-free messages, noise was generally regarded as a problem. The discovery of Stochastic Resonances (SR) in non-linear dynamics brought a shift of perception where noise, rather than representing a problem, became fundamental to system function, especially so in biology. The question now is: to what extent is biological function dependent on random noise. Indeed, it seems feasible that noise also plays an important role in neuronal communication and oscillatory synchronization. Given this approach, it follows that determining Fisher information content could be relevant in neuronal communication. It also seems possible that the principle of least time, and that of the sum over histories, could be important basic principles in understanding the coherence dynamics responsible for action and perception. Ultimately, external noise cancellation combined with intrinsic noise signal embedding and, the use of the principle of least time may be considered an essential step in the organization of central nervous system (CNS) function.

  16. Molecular Biology of Archaebacteria.

    DTIC Science & Technology

    1988-03-31

    Security Classification) Molecular Biology of Archaebacteria .. d. 12. PERSONAL AUTHOR(S) Patrick P. Dennis * 13a. TYPE OF REPORT 13b. TIME COVERED 14...Escherichia coli Research Objectives i) to characterize the principles of gene organization and regulation of gene expression in archaebacteria ; (ii) to...biophysical and molecular terms some of the mechanisms that allow archaebacteria to inhabit extreme environments. Progress - Year I A’ Ribosomal protein

  17. F1 Sterile insect technique: a novel approach for risk assessment of Episimus unguiculus (Lepidoptera: Tortricidae), a candidate biological control agent of Schinus terebinthifolus in the Continental USA

    USDA-ARS?s Scientific Manuscript database

    Federal regulations mandate that researchers in the field of classical weed biological control follow the precautionary principle when proposing the release of an organism that can affect our environment. However, the host range observed in traditional laboratory cage experiments typically is broad...

  18. Middle/High School Students in the Research Laboratory: A Summer Internship Program Emphasizing the Interdisciplinary Nature of Biology

    ERIC Educational Resources Information Center

    McMiller, Tracee; Lee, Tameshia; Saroop, Ria; Green, Tyra; Johnson, Casonya M.

    2006-01-01

    We describe an eight-week summer Young Scientist in Training (YSIT) internship program involving middle and high school students. This program exposed students to current basic research in molecular genetics, while introducing or reinforcing principles of the scientific method and demonstrating the uses of mathematics and chemistry in biology. For…

  19. Essential Concepts and Underlying Theories from Physics, Chemistry, and Mathematics for "Biochemistry and Molecular Biology" Majors

    ERIC Educational Resources Information Center

    Wright, Ann; Provost, Joseph; Roecklein-Canfield, Jennifer A.; Bell, Ellis

    2013-01-01

    Over the past two years, through an NSF RCN UBE grant, the ASBMB has held regional workshops for faculty members from around the country. The workshops have focused on developing lists of Core Principles or Foundational Concepts in Biochemistry and Molecular Biology, a list of foundational skills, and foundational concepts from Physics, Chemistry,…

  20. Biological Principles and Threshold Concepts for Understanding Natural Selection: Implications for Developing Visualizations as a Pedagogic Tool

    ERIC Educational Resources Information Center

    Tibell, Lena A. E.; Harms, Ute

    2017-01-01

    Modern evolutionary theory is both a central theory and an integrative framework of the life sciences. This is reflected in the common references to evolution in modern science education curricula and contexts. In fact, evolution is a core idea that is supposed to support biology learning by facilitating the organization of relevant knowledge. In…

  1. Introducing Experimental Design by Evaluating Efficacy of Herbal Remedies (Do Herbal Remedies Really Work?)

    ERIC Educational Resources Information Center

    Smith, Robert A.; Pontiggia, Laura; Waterman, Carrie; Lichtenwalner, Meghan

    2010-01-01

    This paper is based upon experiments developed as part of a Directed Research course designed to provide undergraduate biology students experience in the principles and processes of the scientific method used in biological research. The project involved the evaluation of herbal remedies used in many parts of the world in the treatment of diseases…

  2. A Constructivist Approach to Inquiry-Based Learning: A TUNEL Assay for the Detection of Apoptosis in Cheek Cells

    ERIC Educational Resources Information Center

    Correiro, Elizabeth E.; Griffin, Leanne R.; Hart, Peter E.

    2008-01-01

    A laboratory exercise is presented that incorporates constructivist principles into a learning experience designed for upper-level university biology courses. The specific objectives for this exercise are as follows: (1) To introduce students to cancer biology and to the regulation of programmed cell death as part of the cell cycle; (2) To engage…

  3. Cellular Gauge Symmetry and the Li Organization Principle: A Mathematical Addendum. Quantifying energetic dynamics in physical and biological systems through a simple geometric tool and geodetic curves.

    PubMed

    Yurkin, Alexander; Tozzi, Arturo; Peters, James F; Marijuán, Pedro C

    2017-12-01

    The present Addendum complements the accompanying paper "Cellular Gauge Symmetry and the Li Organization Principle"; it illustrates a recently-developed geometrical physical model able to assess electronic movements and energetic paths in atomic shells. The model describes a multi-level system of circular, wavy and zigzag paths which can be projected onto a horizontal tape. This model ushers in a visual interpretation of the distribution of atomic electrons' energy levels and the corresponding quantum numbers through rather simple tools, such as compasses, rulers and straightforward calculations. Here we show how this geometrical model, with the due corrections, among them the use of geodetic curves, might be able to describe and quantify the structure and the temporal development of countless physical and biological systems, from Langevin equations for random paths, to symmetry breaks occurring ubiquitously in physical and biological phenomena, to the relationships among different frequencies of EEG electric spikes. Therefore, in our work we explore the possible association of binomial distribution and geodetic curves configuring a uniform approach for the research of natural phenomena, in biology, medicine or the neurosciences. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Toward a Reasoned Classification of Diseases Using Physico-Chemical Based Phenotypes

    PubMed Central

    Schwartz, Laurent; Lafitte, Olivier; da Veiga Moreira, Jorgelindo

    2018-01-01

    Background: Diseases and health conditions have been classified according to anatomical site, etiological, and clinical criteria. Physico-chemical mechanisms underlying the biology of diseases, such as the flow of energy through cells and tissues, have been often overlooked in classification systems. Objective: We propose a conceptual framework toward the development of an energy-oriented classification of diseases, based on the principles of physical chemistry. Methods: A review of literature on the physical chemistry of biological interactions in a number of diseases is traced from the point of view of the fluid and solid mechanics, electricity, and chemistry. Results: We found consistent evidence in literature of decreased and/or increased physical and chemical forces intertwined with biological processes of numerous diseases, which allowed the identification of mechanical, electric and chemical phenotypes of diseases. Discussion: Biological mechanisms of diseases need to be evaluated and integrated into more comprehensive theories that should account with principles of physics and chemistry. A hypothetical model is proposed relating the natural history of diseases to mechanical stress, electric field, and chemical equilibria (ATP) changes. The present perspective toward an innovative disease classification may improve drug-repurposing strategies in the future. PMID:29541031

  5. A MODELING AND SIMULATION LANGUAGE FOR BIOLOGICAL CELLS WITH COUPLED MECHANICAL AND CHEMICAL PROCESSES

    PubMed Central

    Somogyi, Endre; Glazier, James A.

    2017-01-01

    Biological cells are the prototypical example of active matter. Cells sense and respond to mechanical, chemical and electrical environmental stimuli with a range of behaviors, including dynamic changes in morphology and mechanical properties, chemical uptake and secretion, cell differentiation, proliferation, death, and migration. Modeling and simulation of such dynamic phenomena poses a number of computational challenges. A modeling language describing cellular dynamics must naturally represent complex intra and extra-cellular spatial structures and coupled mechanical, chemical and electrical processes. Domain experts will find a modeling language most useful when it is based on concepts, terms and principles native to the problem domain. A compiler must then be able to generate an executable model from this physically motivated description. Finally, an executable model must efficiently calculate the time evolution of such dynamic and inhomogeneous phenomena. We present a spatial hybrid systems modeling language, compiler and mesh-free Lagrangian based simulation engine which will enable domain experts to define models using natural, biologically motivated constructs and to simulate time evolution of coupled cellular, mechanical and chemical processes acting on a time varying number of cells and their environment. PMID:29303160

  6. Genetics and biology of pancreatic ductal adenocarcinoma

    PubMed Central

    Ying, Haoqiang; Dey, Prasenjit; Yao, Wantong; Kimmelman, Alec C.; Draetta, Giulio F.; Maitra, Anirban; DePinho, Ronald A.

    2016-01-01

    With 5-year survival rates remaining constant at 6% and rising incidences associated with an epidemic in obesity and metabolic syndrome, pancreatic ductal adenocarcinoma (PDAC) is on track to become the second most common cause of cancer-related deaths by 2030. The high mortality rate of PDAC stems primarily from the lack of early diagnosis and ineffective treatment for advanced tumors. During the past decade, the comprehensive atlas of genomic alterations, the prominence of specific pathways, the preclinical validation of such emerging targets, sophisticated preclinical model systems, and the molecular classification of PDAC into specific disease subtypes have all converged to illuminate drug discovery programs with clearer clinical path hypotheses. A deeper understanding of cancer cell biology, particularly altered cancer cell metabolism and impaired DNA repair processes, is providing novel therapeutic strategies that show strong preclinical activity. Elucidation of tumor biology principles, most notably a deeper understanding of the complexity of immune regulation in the tumor microenvironment, has provided an exciting framework to reawaken the immune system to attack PDAC cancer cells. While the long road of translation lies ahead, the path to meaningful clinical progress has never been clearer to improve PDAC patient survival. PMID:26883357

  7. Biodiversity prospecting in Nigeria: seeking equity and reciprocity in intellectual property rights through partnership arrangements and capacity building.

    PubMed

    Iwu, M M

    1996-04-01

    The regulation of genetic materials in Nigeria for the isolation of biologically active compounds and/or their exportation from the country fall under the purview of several government departments and parastatals. In principle, biological resources are considered similar to any other natural resource with different levels of stake holders. Specific restrictions, however, apply to the export of food crops. Nigeria is a traditional society where most of biodiversity belongs to what could be appropriately classified as public domain. It has therefore not been easy to carve out property rights from what is generally regarded as communal resources. Private access and occupancy of land and tenure are derived mainly from rights of membership of kindred groups or as custodian of "family' inheritance. The multi-state federal structure allows for negotiations to be conducted mainly at the level of the various State Government Departments responsible for forest resources, and the Federal Government providing the necessary policy guidelines and regulations. The Bioresources Development and Conservation Programme (BDCP), an international NGO based in Nigeria, has adopted an innovative model for biological prospecting based on establishing strategic partnerships and capacity building.

  8. A watershed approach to ecosystem monitoring in Denali National Park and preserve, Alaska

    USGS Publications Warehouse

    Thorsteinson, L.K.; Taylor, D.L.

    1997-01-01

    The National Park Service and the National Biological Service initiated research in Denali National Park and Preserve, a 2.4 million-hectare park in southcentral Alaska, to develop ecological monitoring protocols for national parks in the Arctic/Subarctic biogeographic area. We are focusing pilot studies on design questions, on scaling issues and regionalization, ecosystem structure and function, indicator selection and evaluation, and monitoring technologies. Rock Creek, a headwater stream near Denali headquarters, is the ecological scale for initial testing of a watershed ecosystem approach. Our conceptual model embraces principles of the hydrological cycle, hypotheses of global climate change, and biological interactions of organisms occupying intermediate, but poorly studied, positions in Alaskan food webs. The field approach includes hydrological and depositional considerations and a suite of integrated measures linking key aquatic and terrestrial biota, environmental variables, or defined ecological processes, in order to establish ecological conditions and detect, track, and understand mechanisms of environmental change. Our sampling activities include corresponding measures of physical, chemical, and biological attributes in four Rock Creek habitats believed characteristic of the greater system diversity of Denali. This paper gives examples of data sets, program integration and scaling, and research needs.

  9. Bioengineering Spin-Offs from Dynamical Systems Theory

    NASA Astrophysics Data System (ADS)

    Collins, J. J.

    1997-03-01

    Recently, there has been considerable interest in applying concepts and techniques from dynamical systems and statistical physics to physiological systems. In this talk, we present work dealing which two active topics in this area: stochastic resonance and (2) chaos control. Stochastic resonance is a phenomenon wherein the response of nonlinear system to a weak input signal is optimally enhanced by the presence of a particular level of noise. Here we demonstrate that noise-based techniques can be used to lower sensory detection thresholds in humans. We discuss how from a bioengineering and clinical standpoint, these developments may be particularly relevant for individuals with elevated sensory thresholds, such as older adults and patients with peripheral neuropathy. Chaos control techniques have been applied to a wide range of experimental systems, including biological preparations. The application of chaos control to biological systems has led to speculations that these methods may be clinically useful. Here we demonstrate that the principles of chaos control can be utilized to stabilize underlying unstable periodic orbits in non-chaotic biological systems. We discuss how from a bioengineering and clinical standpoint, these developments may be important for suppressing or eliminating certain types of cardiac arrhythmias.

  10. A MODELING AND SIMULATION LANGUAGE FOR BIOLOGICAL CELLS WITH COUPLED MECHANICAL AND CHEMICAL PROCESSES.

    PubMed

    Somogyi, Endre; Glazier, James A

    2017-04-01

    Biological cells are the prototypical example of active matter. Cells sense and respond to mechanical, chemical and electrical environmental stimuli with a range of behaviors, including dynamic changes in morphology and mechanical properties, chemical uptake and secretion, cell differentiation, proliferation, death, and migration. Modeling and simulation of such dynamic phenomena poses a number of computational challenges. A modeling language describing cellular dynamics must naturally represent complex intra and extra-cellular spatial structures and coupled mechanical, chemical and electrical processes. Domain experts will find a modeling language most useful when it is based on concepts, terms and principles native to the problem domain. A compiler must then be able to generate an executable model from this physically motivated description. Finally, an executable model must efficiently calculate the time evolution of such dynamic and inhomogeneous phenomena. We present a spatial hybrid systems modeling language, compiler and mesh-free Lagrangian based simulation engine which will enable domain experts to define models using natural, biologically motivated constructs and to simulate time evolution of coupled cellular, mechanical and chemical processes acting on a time varying number of cells and their environment.

  11. 'Fish matters': the relevance of fish skin biology to investigative dermatology.

    PubMed

    Rakers, Sebastian; Gebert, Marina; Uppalapati, Sai; Meyer, Wilfried; Maderson, Paul; Sell, Anne F; Kruse, Charli; Paus, Ralf

    2010-04-01

    Fish skin is a multi-purpose tissue that serves numerous vital functions including chemical and physical protection, sensory activity, behavioural purposes or hormone metabolism. Further, it is an important first-line defense system against pathogens, as fish are continuously exposed to multiple microbial challenges in their aquatic habitat. Fish skin excels in highly developed antimicrobial features, many of which have been preserved throughout evolution, and infection defense principles employed by piscine skin are still operative in human skin. This review argues that it is both rewarding and important for investigative dermatologists to revive their interest in fish skin biology, as it provides insights into numerous fundamental issues that are of major relevance to mammalian skin. The basic molecular insights provided by zebrafish in vivo-genomics for genetic, regeneration and melanoma research, the complex antimicrobial defense systems of fish skin and the molecular controls of melanocyte stem cells are just some of the fascinating examples that illustrate the multiple potential uses of fish skin models in investigative dermatology. We synthesize the essentials of fish skin biology and highlight selected aspects that are of particular comparative interest to basic and clinically applied human skin research.

  12. The moss Physcomitrella patens: methods and tools from cultivation to targeted analysis of gene function.

    PubMed

    Strotbek, Christoph; Krinninger, Stefan; Frank, Wolfgang

    2013-01-01

    To comprehensively understand the major processes in plant biology, it is necessary to study a diverse set of species that represent the complexity of plants. This research will help to comprehend common conserved mechanisms and principles, as well as to elucidate those mechanisms that are specific to a particular plant clade. Thereby, we will gain knowledge about the invention and loss of mechanisms and their biological impact causing the distinct specifications throughout the plant kingdom. Since the establishment of transgenic plants, these studies concentrate on the elucidation of gene functions applying an increasing repertoire of molecular techniques. In the last two decades, the moss Physcomitrella patens joined the established set of plant models based on its evolutionary position bridging unicellular algae and vascular plants and a number of specific features alleviating gene function analysis. Here, we want to provide an overview of the specific features of P. patens making it an interesting model for many research fields in plant biology, to present the major achievements in P. patens genetic engineering, and to introduce common techniques to scientists who intend to use P. patens as a model in their research activities.

  13. Chemical characterization and bioactive properties of Geranium molle L.: from the plant to the most active extract and its phytochemicals.

    PubMed

    Graça, V C; Barros, Lillian; Calhelha, Ricardo C; Dias, Maria Inês; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C F R; Santos, P F

    2016-05-18

    After a period of indifference, in which synthetic compounds were favored, there is an increasing interest in the study of the biological properties of plants and the active principles responsible for their therapeutic properties. Geranium molle L. has been used in the Portuguese folk medicine for the treatment of various ailments including cancer but, unlike many of the species from the Geranium genus, its phytochemical characterization and biological activity are virtually unexplored. In this study a G. molle sample from Trás-os-Montes, north-eastern Portugal, was chemically characterized regarding nutritional value, free sugars, organic acids, fatty acids and tocopherols, and several aqueous (decoction, infusion) and organic (n-hexane, dichloromethane, ethyl acetate, acetone, methanol) extracts of the plant were assessed for their bioactive properties. The antioxidant activity was evaluated by means of the free radicals scavenging activity, reducing power and inhibition of lipid peroxidation. The cytotoxicity of the different extracts was assessed in vitro against several human cancer cell lines (breast, lung, cervical and hepatocellular carcinomas) and, additionally, their hepatotoxicity was evaluated using a porcine liver primary cell culture. G. molle was shown to be rich in carbohydrates and proteins, providing tocopherols and essential fatty acids. Amongst the various extracts, the acetone extract was found to have the highest content of phenolic compounds (mainly ellagitannins, but also some flavone and flavonol glycosides) as well as the highest antioxidant and cytotoxic activities. To the best of our knowledge, this is the first report on the chemical composition and bioactive properties of G. molle.

  14. A New "Principal Principle" (#14) of Physical Activity Education Is Emerging

    ERIC Educational Resources Information Center

    Zeigler, Earle F.

    2011-01-01

    There is every reason to believe that a new "principal principle" of physical activity education is emerging. In this article, the author talks about the new "principal principle"(#14) of physical education. Revisiting a historical milestone in the field's history to explain the origin of the term "principal principle," Dr. Arthur H. Steinhaus,…

  15. Process Pharmacology: A Pharmacological Data Science Approach to Drug Development and Therapy.

    PubMed

    Lötsch, Jörn; Ultsch, Alfred

    2016-04-01

    A novel functional-genomics based concept of pharmacology that uses artificial intelligence techniques for mining and knowledge discovery in "big data" providing comprehensive information about the drugs' targets and their functional genomics is proposed. In "process pharmacology", drugs are associated with biological processes. This puts the disease, regarded as alterations in the activity in one or several cellular processes, in the focus of drug therapy. In this setting, the molecular drug targets are merely intermediates. The identification of drugs for therapeutic or repurposing is based on similarities in the high-dimensional space of the biological processes that a drug influences. Applying this principle to data associated with lymphoblastic leukemia identified a short list of candidate drugs, including one that was recently proposed as novel rescue medication for lymphocytic leukemia. The pharmacological data science approach provides successful selections of drug candidates within development and repurposing tasks. © 2016 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

  16. Controlling legs for locomotion-insights from robotics and neurobiology.

    PubMed

    Buschmann, Thomas; Ewald, Alexander; von Twickel, Arndt; Büschges, Ansgar

    2015-06-29

    Walking is the most common terrestrial form of locomotion in animals. Its great versatility and flexibility has led to many attempts at building walking machines with similar capabilities. The control of walking is an active research area both in neurobiology and robotics, with a large and growing body of work. This paper gives an overview of the current knowledge on the control of legged locomotion in animals and machines and attempts to give walking control researchers from biology and robotics an overview of the current knowledge in both fields. We try to summarize the knowledge on the neurobiological basis of walking control in animals, emphasizing common principles seen in different species. In a section on walking robots, we review common approaches to walking controller design with a slight emphasis on biped walking control. We show where parallels between robotic and neurobiological walking controllers exist and how robotics and biology may benefit from each other. Finally, we discuss where research in the two fields diverges and suggest ways to bridge these gaps.

  17. Fuel-Mediated Transient Clustering of Colloidal Building Blocks.

    PubMed

    van Ravensteijn, Bas G P; Hendriksen, Wouter E; Eelkema, Rienk; van Esch, Jan H; Kegel, Willem K

    2017-07-26

    Fuel-driven assembly operates under the continuous influx of energy and results in superstructures that exist out of equilibrium. Such dissipative processes provide a route toward structures and transient behavior unreachable by conventional equilibrium self-assembly. Although perfected in biological systems like microtubules, this class of assembly is only sparsely used in synthetic or colloidal analogues. Here, we present a novel colloidal system that shows transient clustering driven by a chemical fuel. Addition of fuel causes an increase in hydrophobicity of the building blocks by actively removing surface charges, thereby driving their aggregation. Depletion of fuel causes reappearance of the charged moieties and leads to disassembly of the formed clusters. This reassures that the system returns to its initial, equilibrium state. By taking advantage of the cyclic nature of our system, we show that clustering can be induced several times by simple injection of new fuel. The fuel-mediated assembly of colloidal building blocks presented here opens new avenues to the complex landscape of nonequilibrium colloidal structures, guided by biological design principles.

  18. Chrononutrition against Oxidative Stress in Aging

    PubMed Central

    Garrido, M.; Terrón, M. P.; Rodríguez, A. B.

    2013-01-01

    Free radicals and oxidative stress have been recognized as important factors in the biology of aging and in many age-associated degenerative diseases. Antioxidant systems deteriorate during aging. It is, thus, considered that one way to reduce the rate of aging and the risk of chronic disease is to avoid the formation of free radicals and reduce oxidative stress by strengthening antioxidant defences. Phytochemicals present in fruits, vegetables, grains, and other foodstuffs have been linked to reducing the risk of major oxidative stress-induced diseases. Some dietary components of foods possess biological activities which influence circadian rhythms in humans. Chrononutrition studies have shown that not only the content of food, but also the time of ingestion contributes to the natural functioning of the circadian system. Dietary interventions with antioxidant-enriched foods taking into account the principles of chrononutrition are of particular interest for the elderly since they may help amplify the already powerful benefits of phytochemicals as natural instruments with which to prevent or delay the onset of common age-related diseases. PMID:23861994

  19. Space ecosynthesis: An approach to the design of closed ecosystems for use in space

    NASA Technical Reports Server (NTRS)

    Macelroy, R. D.; Averner, M. M.

    1978-01-01

    The use of closed ecological systems for the regeneration of wastes, air, and water is discussed. It is concluded that such systems, if they are to be used for the support of humans in space, will require extensive mechanical and physico-chemical support. The reason for this is that the buffering capacity available in small systems is inadequate, and that natural biological and physical regulatory mechanisms rapidly become inoperative. It is proposed that mathematical models of the dynamics of a closed ecological system may provide the best means of studying the initial problems of ecosystem closure. A conceptual and mathematical model of a closed ecosystem is described which treats the biological components as a farm, calculates the rates of flow of elements through the system by mass-balance techniques and control theory postulates, and can evaluate the requirements for mechanical buffering activities. It is suggested that study of the closure of ecosystems can significantly aid in the establishment of general principles of ecological systems.

  20. Physical models of biological information and adaptation.

    PubMed

    Stuart, C I

    1985-04-07

    The bio-informational equivalence asserts that biological processes reduce to processes of information transfer. In this paper, that equivalence is treated as a metaphor with deeply anthropomorphic content of a sort that resists constitutive-analytical definition, including formulation within mathematical theories of information. It is argued that continuance of the metaphor, as a quasi-theoretical perspective in biology, must entail a methodological dislocation between biological and physical science. It is proposed that a general class of functions, drawn from classical physics, can serve to eliminate the anthropomorphism. Further considerations indicate that the concept of biological adaptation is central to the general applicability of the informational idea in biology; a non-anthropomorphic treatment of adaptive phenomena is suggested in terms of variational principles.

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