WorldWideScience

Sample records for biological physics methods

  1. Combining physical, cultural and biological methods: prospects for integrated non-chemical weed management strategies

    OpenAIRE

    Hatcher, Lecturer Paul; Melander, Senior scientist Bo

    2003-01-01

    Physical, cultural and biological methods for weed control have developed largely independently and are often concerned with weed control in different systems: physical and cultural control in annual crops and biocontrol in extensive grasslands. We discuss the strengths and limitations of four physical and cultural methods for weed control: mechanical, thermal, cutting, and intercropping, and the advantages and disadvantages of combining biological control with them. These physical and cult...

  2. Dielectric relaxation in biological systems physical principles, methods, and applications

    CERN Document Server

    Feldman, Yuri

    2015-01-01

    This title covers the theoretical basis and practical aspects of the study of dielectric properties of biological systems, such as water, electrolyte and polyelectrolytes, solutions of biological macromolecules, cells suspensions and cellular systems.

  3. Radiation effects analysis in a group of interventional radiologists using biological and physical dosimetry methods

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, M., E-mail: WEMLmirapas@iqn.upv.e [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Montoro, A.; Almonacid, M. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Ferrer, S. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Barquinero, J.F. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Tortosa, R. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Verdu, G. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Rodriguez, P. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Barrios, L.L. [Department of Physiology and Cellular Biology, Unit of Cellular Biology (UAB) (Spain); Villaescusa, J.I. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain)

    2010-08-15

    Interventional radiologists and staff members are frequently exposed to protracted and fractionated low doses of ionizing radiation, which extend during all their professional activities. These exposures can derive, due to the effects of direct and scattered radiation, in deterministic effects (radiodermitis, aged skin, cataracts, telangiectasia in nasal region, vasocellular epitelioms, hands depilation) and/or stochastic ones (cancer incidence). A methodology has been proposed for estimating the radiation risk or detriment from a group of six exposed interventional radiologists of the Hospital Universitario La Fe (Valencia, Spain), which had developed general exposition symptoms attributable to deterministic effects of ionizing radiation. Equivalent doses have been periodically registered using TLD's and wrist dosimeters, H{sub p}(10) and H{sub p}(0.07), respectively, and estimated through the observation of translocations in lymphocytes of peripheral blood (biological methods), by extrapolating the yield of translocations to their respective dose-effect curves. The software RADRISK has been applied for estimating radiation risks in these occupational radiation exposures. This software is based on transport models from epidemiological studies of population exposed to external sources of ionizing radiation, such as Hiroshima and Nagasaki atomic bomb survivors [UNSCEAR, Sources and effects of ionizing radiation: 2006 report to the general assembly, with scientific annexes. New York: United Nations; 2006]. The minimum and maximum average excess ratio for skin cancer has been, using wrist physical doses, of [1.03x10{sup -3}, 5.06x10{sup -2}], concluding that there is not an increased risk of skin cancer incidence. The minimum and maximum average excess ratio for leukemia has been, using TLD physical doses, of [7.84x10{sup -2}, 3.36x10{sup -1}], and using biological doses, of [1.40x10{sup -1}, 1.51], which is considerably higher than incidence rates, showing an

  4. Effects of sterilization methods on the physical, chemical, and biological properties of silk fibroin membranes.

    Science.gov (United States)

    de Moraes, Mariana Agostini; Weska, Raquel Farias; Beppu, Marisa Masumi

    2014-05-01

    Silk fibroin has been widely explored for many biomedical applications, due to its biocompatibility and biodegradability. Sterilization is a fundamental step in biomaterials processing and it must not jeopardize the functionality of medical devices. The aim of this study was to analyze the influence of different sterilization methods in the physical, chemical, and biological characteristics of dense and porous silk fibroin membranes. Silk fibroin membranes were treated by several procedures: immersion in 70% ethanol solution, ultraviolet radiation, autoclave, ethylene oxide, and gamma radiation, and were analyzed by scanning electron microscopy, Fourier-transformed infrared spectroscopy (FTIR), X-ray diffraction, tensile strength and in vitro cytotoxicity to Chinese hamster ovary cells. The results indicated that the sterilization methods did not cause perceivable morphological changes in the membranes and the membranes were not toxic to cells. The sterilization methods that used organic solvent or an increased humidity and/or temperature (70% ethanol, autoclave, and ethylene oxide) increased the silk II content in the membranes: the dense membranes became more brittle, while the porous membranes showed increased strength at break. Membranes that underwent sterilization by UV and gamma radiation presented properties similar to the nonsterilized membranes, mainly for tensile strength and FTIR results. PMID:24259492

  5. Quantum physics meets biology

    CERN Document Server

    Arndt, Markus; Vedral, Vlatko

    2009-01-01

    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the last decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world view of quantum coherences, entanglement and other non-classical effects, has been heading towards systems of increasing complexity. The present perspective article shall serve as a pedestrian guide to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future quantum biology, its current status, recent experimental progress and also the restrictions that nature imposes on bold extrapolat...

  6. Biological scaling and physics

    Indian Academy of Sciences (India)

    A R P Rau

    2002-09-01

    Kleiber’s law in biology states that the specific metabolic rate (metabolic rate per unit mass) scales as -1/4 in terms of the mass of the organism. A long-standing puzzle is the (- 1/4) power in place of the usual expectation of (- 1/3) based on the surface to volume ratio in three-dimensions. While recent papers by physicists have focused exclusively on geometry in attempting to explain the puzzle, we consider here a specific law of physics that governs fluid flow to show how the (- 1/4) power arises under certain conditions. More generally, such a line of approach that identifies a specific physical law as involved and then examines the implications of a power law may illuminate better the role of physics in biology.

  7. Biological Evolution and Statistical Physics

    OpenAIRE

    Drossel, Barbara

    2001-01-01

    This review is an introduction to theoretical models and mathematical calculations for biological evolution, aimed at physicists. The methods in the field are naturally very similar to those used in statistical physics, although the majority of publications appeared in biology journals. The review has three parts, which can be read independently. The first part deals with evolution in fitness landscapes and includes Fisher's theorem, adaptive walks, quasispecies models, effects of finite popu...

  8. Assessment of occupational exposure and individual radiosensitivity in people exposed to radiation using methods of physical and biological dosimetry

    International Nuclear Information System (INIS)

    This paper examined people professionally in contact with sources of ionizing radiation.The incidence of chromosomal aberrations, the radionuclide content in the urine of the radiochemical method and calculation of internal doses based on the results of direct measurement of the concentration of incorporated radionuclides 137Cs and 241Am using human radiation spectrometer (HRS). According to the results of physical and biological dosimetry identified individual cumulative doses and the ratio defined cohort surveyed by radiosensitivity Key words: chromosomal aberrations, physical methods of dosimetry, radiation sensitivity, ionizing radiation, biodosimetry

  9. Comparison in the determination of absorbed dose by biological and physical methods to patients in treatment of cardiac intervention

    International Nuclear Information System (INIS)

    The use of less invasive procedures, lower risk and quick recovery as cardiac intervention have proven to be an efficient alternative to reestablish the correct bloodstream of the patient. In this case the patient is subjected to values of absorbed dose above to which is subjected in a study with X-rays for medical diagnosis, and this can cause radiation injuries to the skin. The target organ, in this case can be exposed to doses of 2 Gy above. Different methods to estimate the dose were use, physical by Radiochromic film, as biological by dicentric analysis. Both methods provided additional information demonstrating thus the risk in the target organ and the patient. The most reliable biological indicator of exposure to ionizing radiation is the study of chromosomal aberrations, specifically dicentric in human lymphocytes. This test allowed establishing the exposure dose depending of the damage. (Author)

  10. Catalogue of methods of calculation, interpolation, smoothing, and reduction for the physical, chemical, and biological parameters of deep hydrology (CATMETH) (NODC Accession 7700442)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The document presents the methods, formulas and citations used by the BNDO to process physical, chemical, and biological data for deep hydrology including...

  11. Basic radiotherapy physics and biology

    CERN Document Server

    Chang, David S; Das, Indra J; Mendonca, Marc S; Dynlacht, Joseph R

    2014-01-01

    This book is a concise and well-illustrated review of the physics and biology of radiation therapy intended for radiation oncology residents, radiation therapists, dosimetrists, and physicists. It presents topics that are included on the Radiation Therapy Physics and Biology examinations and is designed with the intent of presenting information in an easily digestible format with maximum retention in mind. The inclusion of mnemonics, rules of thumb, and reader-friendly illustrations throughout the book help to make difficult concepts easier to grasp. Basic Radiotherapy Physics and Biology is a

  12. Nuclear physics and biology

    International Nuclear Information System (INIS)

    This paper is about nuclear instrumentation and biological concepts, based on images from appropriate Β detectors. First, three detectors are described: the SOFI detector, for gene mapping, the SOFAS detector, for DNA sequencing and the RIHR detector, for in situ hybridization. Then, the paper presents quantitative imaging in molecular genetic and functional imaging. (TEC)

  13. How physics can inspire biology

    Science.gov (United States)

    Kornyshev, Alexei

    2009-07-01

    In July 1997 Adrian Parsegian, a biophysicist at the National Institutes of Health in the US and a former president of the Biophysical Society, published an article in Physics Today in which he outlined his thoughts about the main obstacles to a happy marriage between physics and biology. Parsegian started his article with a joke about a physicist talking to his biology-trained friend.

  14. From biologically-inspired physics to physics-inspired biology From biologically-inspired physics to physics-inspired biology

    Science.gov (United States)

    Kornyshev, Alexei A.

    2010-10-01

    D student at the Frumkin Institute in Moscow attending hot theoretical seminars chaired by Benjamin Levich (1917-1986, a pupil of Landau and the founding father of physical-chemical hydrodynamics), I particularly remember one of his many jokes he used to spice up his seminar. When some overly enthusiastic speaker was telling us with 100% confidence how the electron transfers between atomic moieties in a solvent near an electrode, and what the molecules exactly do to promote the transfer, he used to ask the speaker: 'How do you know it? Have you been there?' Today this is no longer a question or even a joke. We have plenty of experimental tools to 'get there'. The list of such techniques is too long to cover fully, I may just refer to FIONA (fluorescence imaging with nanometer accuracy) which allows us to trace the motion of myosin on actin or kinesin on microtubules and similar aspects of protein motility in vivo and in vitro (fluorescence methods were at the center of the Biological and Molecular Machine Program at Kavli ITP, Santa Barbara, where the founders of those techniques taught us what we can learn using them) or visualizing the positions of adsorbed counterions on DNA by synchrotron radiation. Therefore, the following dogmas can be given: Dogma 1: 'Seeing is believing'. Once, I asked an Assistant Professor from one of the top US universities, who was preaching such methods, had he tried to plot his data in some coordinates, where I would have expected his data to lie on a straight line. The answer was, 'Come on, what you speak about is 20th century science; it's no longer interesting!' I am afraid he was not unique in his generation, voting for what I would call 'MTV-science'. This science does make you dance, but on its own is not sufficient without a deep theoretical analysis of what you actually see. Otherwise, 'what you see is what you get' and not more. Dogma 2: 'A theory must contain not more than exponential functions, logarithms and alike. Otherwise the

  15. AFM₁ in Milk: Physical, Biological, and Prophylactic Methods to Mitigate Contamination.

    Science.gov (United States)

    Giovati, Laura; Magliani, Walter; Ciociola, Tecla; Santinoli, Claudia; Conti, Stefania; Polonelli, Luciano

    2015-10-01

    Aflatoxins (AFs) are toxic, carcinogenic, immunosuppressive secondary metabolites produced by some Aspergillus species which colonize crops, including many dietary staple foods and feed components. AFB₁ is the prevalent and most toxic among AFs. In the liver, it is biotransformed into AFM₁, which is then excreted into the milk of lactating mammals, including dairy animals. AFM₁ has been shown to be cause of both acute and chronic toxicoses. The presence of AFM₁ in milk and dairy products represents a worldwide concern since even small amounts of this metabolite may be of importance as long-term exposure is concerned. Contamination of milk may be mitigated either directly, decreasing the AFM₁ content in contaminated milk, or indirectly, decreasing AFB₁ contamination in the feed of dairy animals. Current strategies for AFM₁ mitigation include good agricultural practices in pre-harvest and post-harvest management of feed crops (including storage) and physical or chemical decontamination of feed and milk. However, no single strategy offers a complete solution to the issue. PMID:26512694

  16. AFM1 in Milk: Physical, Biological, and Prophylactic Methods to Mitigate Contamination

    Directory of Open Access Journals (Sweden)

    Laura Giovati

    2015-10-01

    Full Text Available Aflatoxins (AFs are toxic, carcinogenic, immunosuppressive secondary metabolites produced by some Aspergillus species which colonize crops, including many dietary staple foods and feed components. AFB1 is the prevalent and most toxic among AFs. In the liver, it is biotransformed into AFM1, which is then excreted into the milk of lactating mammals, including dairy animals. AFM1 has been shown to be cause of both acute and chronic toxicoses. The presence of AFM1 in milk and dairy products represents a worldwide concern since even small amounts of this metabolite may be of importance as long-term exposure is concerned. Contamination of milk may be mitigated either directly, decreasing the AFM1 content in contaminated milk, or indirectly, decreasing AFB1 contamination in the feed of dairy animals. Current strategies for AFM1 mitigation include good agricultural practices in pre-harvest and post-harvest management of feed crops (including storage and physical or chemical decontamination of feed and milk. However, no single strategy offers a complete solution to the issue.

  17. Bacterial exposure to metal-oxide nanoparticles: Methods, physical interactions, and biological effects

    Science.gov (United States)

    Horst, Allison Marie

    Nanotechnology is a major endeavor of this century, with proposed applications in fields ranging from agriculture to energy to medicine. Nanoscale titanium dioxide (nano-TiO2) is among the most widely produced nanoparticles worldwide, and already exists in consumer products including impermanent personal care products and surface coatings. Inevitably, nano-TiO2 will be transported into the environment via consumer or industrial waste, where its effects on organisms are largely unknown. Out of concern for the possible ill-effects of nanoparticles in the environment, there is now a field of study in nanotoxicology. Bacteria are ideal organisms for nanotoxicology research because they are environmentally important, respond rapidly to intoxication, and provide evidence for effects in higher organisms. My doctoral research focuses on the effects and interactions of nano-TiO2 in aqueous systems with planktonic bacteria. This dissertation describes four projects and the outcomes of the research: (1) A discovery, using a combination of environmental- and cryogenic-scanning electron microscopy and dynamic light scattering (DLS), that initially agglomerated nano-TiO2 is dispersed upon bacterial contact, as nanoparticles preferentially sorbed to cell surfaces. (2) Establishment of a method to disperse nanoparticles in an aqueous culture medium for nanotoxicology studies. A combination of electrostatic repulsion, steric hindrance and sonication yielded a high initial level of nano-TiO2 dispersion (i.e. E. coli growth and membrane processes. Together, this research is towards: better understanding outcomes of interactions between nanoparticles and bacteria, advancing methods in the relatively new field of nanotoxicology that are transferable to other nanoparticle and media chemistries, and improving our understanding of structure-activity relationships (e.g. size and doping effects) leading to intoxication in environmental organisms.

  18. Statistics in science the foundations of statistical methods in biology, physics and economics

    CERN Document Server

    Costantini, Domenico

    1990-01-01

    An inference may be defined as a passage of thought according to some method. In the theory of knowledge it is customary to distinguish deductive and non-deductive inferences. Deductive inferences are truth preserving, that is, the truth of the premises is preserved in the con­ clusion. As a result, the conclusion of a deductive inference is already 'contained' in the premises, although we may not know this fact until the inference is performed. Standard examples of deductive inferences are taken from logic and mathematics. Non-deductive inferences need not preserve truth, that is, 'thought may pass' from true premises to false conclusions. Such inferences can be expansive, or, ampliative in the sense that the performances of such inferences actually increases our putative knowledge. Standard non-deductive inferences do not really exist, but one may think of elementary inductive inferences in which conclusions regarding the future are drawn from knowledge of the past. Since the body of scientific knowledge i...

  19. The Physics of Marine Biology.

    Science.gov (United States)

    Conn, Kathleen

    1992-01-01

    Discusses ways in which marine biology can be integrated into the physics classroom. Topics suggested for incorporation include the harmonic motion of ocean waves, ocean currents, the interaction of visible light with ocean water, pressure, light absorption, and sound transfer in water. (MDH)

  20. Stochastic Methods in Biology

    CERN Document Server

    Kallianpur, Gopinath; Hida, Takeyuki

    1987-01-01

    The use of probabilistic methods in the biological sciences has been so well established by now that mathematical biology is regarded by many as a distinct dis­ cipline with its own repertoire of techniques. The purpose of the Workshop on sto­ chastic methods in biology held at Nagoya University during the week of July 8-12, 1985, was to enable biologists and probabilists from Japan and the U. S. to discuss the latest developments in their respective fields and to exchange ideas on the ap­ plicability of the more recent developments in stochastic process theory to problems in biology. Eighteen papers were presented at the Workshop and have been grouped under the following headings: I. Population genetics (five papers) II. Measure valued diffusion processes related to population genetics (three papers) III. Neurophysiology (two papers) IV. Fluctuation in living cells (two papers) V. Mathematical methods related to other problems in biology, epidemiology, population dynamics, etc. (six papers) An important f...

  1. Main Achievements 2003-2004 - Interdisciplinary Research - Applications of nuclear methods to biomedical physics, environmental biology, environmental physics, and medical physics - Magnetic resonance imaging and spectroscopy

    International Nuclear Information System (INIS)

    Biomedical studies have been carried out at the IFJ PAN using magnetic resonance imaging and spectroscopy to develop new methods of noninvasive diagnostics (e.g. spinal cord injuries using diffusion tensor imaging). It has been shown for the first time that in the human cervical spinal cord at high gradient factor b-values, up to 7000 s/mm2, diffusion is biexponential. The slow diffusion component could be useful in diagnosing White Matter fiber pathology. The first experiment of simultaneous functional magnetic resonance imaging fMRI in the rat spinal cord and brain has also been performed. Functional activity was evoked by electrical stimulation of the rat's forepaw. The time-course of the activated voxels from the brain and spinal cord were analysed and compared. High correlation (p≤0.001) of the detected activity to the applied stimulation was demonstrated. This experiment, carried out in collaboration with the Institute for Biodiagnostics in Clagary, should be extended into clinical applications in the human central nervous system

  2. Is Biology based on Physics?

    Science.gov (United States)

    Goradia, Shantilal

    2015-04-01

    The equation on Boltsmann's tomb is S = K log W, giving 137 = 10E60 where 10E60 closely stands for the age of the universe in Plank times. We wish we could add ``137 = 10E60'' on his tomb as a contribution leading physics towards information in biology as explained in our book ``Quantum Consciousness - the Road to Reality.'' (1) We draft our speculation that such a step may explain the underlying physical cause for mutations. Tiny immeasurable and slow changes well beyond the tenth digit of fine structure constant may suffice to change the information system in constituent particles of nucleotides with their external effects forcing changes in the genetic code with successful changes resulting into mutations. (2) Our quantum mechanical published derivation of the strong coupling implies gravity as a cumulative effect of quantum mechanical particles further implying that the universal constant of gravity (G) can not be constant everywhere. (1) and (2) put together should remove Darwin's confusion about the constancy of gravity. Moving planets and Sunstorms should also cause changes in G on earth unnoticeable to mankind, but large enough to have an impact on the internal particles of nucleotides which should implicitly have an external effect on the genetic code per our theory.

  3. Methods for calculating the absolute entropy and free energy of biological systems based on ideas from polymer physics.

    Science.gov (United States)

    Meirovitch, Hagai

    2010-01-01

    The commonly used simulation techniques, Metropolis Monte Carlo (MC) and molecular dynamics (MD) are of a dynamical type which enables one to sample system configurations i correctly with the Boltzmann probability, P(i)(B), while the value of P(i)(B) is not provided directly; therefore, it is difficult to obtain the absolute entropy, S approximately -ln P(i)(B), and the Helmholtz free energy, F. With a different simulation approach developed in polymer physics, a chain is grown step-by-step with transition probabilities (TPs), and thus their product is the value of the construction probability; therefore, the entropy is known. Because all exact simulation methods are equivalent, i.e. they lead to the same averages and fluctuations of physical properties, one can treat an MC or MD sample as if its members have rather been generated step-by-step. Thus, each configuration i of the sample can be reconstructed (from nothing) by calculating the TPs with which it could have been constructed. This idea applies also to bulk systems such as fluids or magnets. This approach has led earlier to the "local states" (LS) and the "hypothetical scanning" (HS) methods, which are approximate in nature. A recent development is the hypothetical scanning Monte Carlo (HSMC) (or molecular dynamics, HSMD) method which is based on stochastic TPs where all interactions are taken into account. In this respect, HSMC(D) can be viewed as exact and the only approximation involved is due to insufficient MC(MD) sampling for calculating the TPs. The validity of HSMC has been established by applying it first to liquid argon, TIP3P water, self-avoiding walks (SAW), and polyglycine models, where the results for F were found to agree with those obtained by other methods. Subsequently, HSMD was applied to mobile loops of the enzymes porcine pancreatic alpha-amylase and acetylcholinesterase in explicit water, where the difference in F between the bound and free states of the loop was calculated. Currently

  4. Biological detector and method

    Energy Technology Data Exchange (ETDEWEB)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F

    2014-04-15

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  5. Biological detector and method

    Energy Technology Data Exchange (ETDEWEB)

    Sillerud, Laurel; Alam, Todd M.; McDowell, Andrew F.

    2015-11-24

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  6. Biological detector and method

    Science.gov (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F

    2013-02-26

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  7. Bridging Physics and Biology Teaching through Modeling

    OpenAIRE

    Hoskinson, Anne-Marie; Couch, Brian A.; Zwickl, Benjamin M.; Hinko, Kathleen; Caballero, Marcos D.

    2013-01-01

    As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life sciences majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both sciences t...

  8. Biology is the new physics

    OpenAIRE

    Hunter, Philip

    2010-01-01

    The application of mathematics and computer science to biology is changing the nature of research. Philip Hunter explores the cross-fertilization of ideas between the disciplines and how it creates new job opportunities for biologists and mathematicians

  9. Biological physics and synchrotron radiation

    International Nuclear Information System (INIS)

    This conference deals with the applications of synchrotron radiation to current problems in biology and medicine. Seven sessions take stock on the subject: sources and detectors; inelastic scattering and dynamics; muscle diffraction; reaction mechanisms; macromolecular assemblies; medical applications; imaging and spectroscopy. The document presents the papers abstracts. (A.L.B.)

  10. Biological physics and synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Filhol, J.M.; Chavanne, J. [European Synchrotron Radiation Facility, 38 - Grenoble (France); Weckert, E. [Hasylab at Desy, Hamburg (Germany)] [and others

    2001-07-01

    This conference deals with the applications of synchrotron radiation to current problems in biology and medicine. Seven sessions take stock on the subject: sources and detectors; inelastic scattering and dynamics; muscle diffraction; reaction mechanisms; macromolecular assemblies; medical applications; imaging and spectroscopy. The document presents the papers abstracts. (A.L.B.)

  11. Intermediate physics for medicine and biology

    CERN Document Server

    Hobbie, Russell K

    2015-01-01

    This classic text has been used in over 20 countries by advanced undergraduate and beginning graduate students in biophysics, physiology, medical physics, neuroscience, and biomedical engineering. It bridges the gap between an introductory physics course and the application of physics to the life and biomedical sciences. Extensively revised and updated, the fifth edition incorporates new developments at the interface between physics and biomedicine. New coverage includes cyclotrons, photodynamic therapy, color vision, x-ray crystallography, the electron microscope, cochlear implants, deep brain stimulation, nanomedicine, and other topics highlighted in the National Research Council report BIO2010. As with the previous edition, the first half of the text is primarily biological physics, emphasizing the use of ideas from physics to understand biology and physiology, and the second half is primarily medical physics, describing the use of physics in medicine for diagnosis (mainly imaging) and therapy. Among the m...

  12. Modelling biological complexity: a physical scientist's perspective

    OpenAIRE

    Coveney, Peter V.; Fowler, Philip W.

    2005-01-01

    We discuss the modern approaches of complexity and self-organization to understanding dynamical systems and how these concepts can inform current interest in systems biology. From the perspective of a physical scientist, it is especially interesting to examine how the differing weights given to philosophies of science in the physical and biological sciences impact the application of the study of complexity. We briefly describe how the dynamics of the heart and circadian rhythms, canonical exa...

  13. Physical Biology : challenges for our second decade

    Science.gov (United States)

    Levine, Herbert

    2014-06-01

    It is quite an honor to be asked to become the third editor-in-chief of Physical Biology . I am following in the footsteps of Tim Newman, who served with energy and enthusiasm. Hopefully, the entire community fully appreciates his contributions to moving the field forward. Thank you, Tim! With the honor, however, goes a clear responsibility. Our journal has survived its birth pangs and emerged as a serious venue for publishing quality research papers using physical science to address the workings of living matter. With the support of scientists in this field and with the ongoing commitment of the IOP, we have successfully reached adolescence. Yet, there is clearly much room to grow and there are clear challenges in defining and maintaining our special niche in the publishing landscape. In this still-developing state, the journal very much mimics the state of the field of physical biology itself. Few scientists continue to question the relevance of physical science for the investigation of the living world. But, will our new perspective and the methods that come with it really lead to radically new principles of how life works? Or, will breakthroughs continue to come from experimental biology (perhaps aided by the traditional physicist-as-tool-builder paradigm), leaving us to put quantitative touches on established fundamentals? In thinking about these questions for the field and for the journal, I have tried to understand what is really unique about our joint endeavors. I have become convinced that living matter represents a new challenge to our physical-science based conceptual framework. Not only is it far from equilibrium, as has been generally recognized, but it violates our simple notions of the separability of constituents, their interactions and the resulting large-scale behavior. Unlike, say, atomic physicists who can do productive research while safely ignoring the latest developments in QCD (let alone particle physics at higher energies), we do not yet

  14. Basic biology in health physics

    International Nuclear Information System (INIS)

    This report describes the consequences of the interaction of ionizing radiation with living cells and tissues. The basic processes of living cells, which are relevant to an understanding of health physics problems, are outlined with particular reference to cell-death, cancer induction and genetic effects. (author)

  15. Nuclear physics mathematical methods

    International Nuclear Information System (INIS)

    The nuclear physics mathematical methods, applied to the collective motion theory, to the reduction of the degrees of freedom and to the order and disorder phenomena; are investigated. In the scope of the study, the following aspects are discussed: the entropy of an ensemble of collective variables; the interpretation of the dissipation, applying the information theory; the chaos and the universality; the Monte-Carlo method applied to the classical statistical mechanics and quantum mechanics; the finite elements method, and the classical ergodicity

  16. Physics and Size in Biological Systems.

    Science.gov (United States)

    Barnes, George

    1989-01-01

    Described is the subject of biological scaling for physics teachers including examples and in-depth reading. Topics are elements of scaling, terminal velocities, Lilliputian and Brobdingnagian, brain evolution, dolphin echolocation, surface tension, gravity change, food and oxygen, and seeing. Ten references on physics and size, and ten questions…

  17. Bridging Physics and Biology Teaching through Modeling

    CERN Document Server

    Hoskinson, Anne-Marie; Zwickl, Benjamin M; Hinko, Kathleen; Caballero, Marcos D

    2013-01-01

    As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life sciences majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both fundamental sciences that rely on observations and measurements to construct models of the natural world. In the present theoretical article, we propose that efforts to bridge the teaching of these two disciplines must emphasize shared scientific practices, particularly scientific modeling. We define modeling using language common to both disciplines and highlight how an understanding of the modeling process can help reconcile apparent differences between physics and biology. We elaborate how models can be used for explanatory, pre...

  18. Ontology of physics for biology: representing physical dependencies as a basis for biological processes

    Science.gov (United States)

    2013-01-01

    Background In prior work, we presented the Ontology of Physics for Biology (OPB) as a computational ontology for use in the annotation and representations of biophysical knowledge encoded in repositories of physics-based biosimulation models. We introduced OPB:Physical entity and OPB:Physical property classes that extend available spatiotemporal representations of physical entities and processes to explicitly represent the thermodynamics and dynamics of physiological processes. Our utilitarian, long-term aim is to develop computational tools for creating and querying formalized physiological knowledge for use by multiscale “physiome” projects such as the EU’s Virtual Physiological Human (VPH) and NIH’s Virtual Physiological Rat (VPR). Results Here we describe the OPB:Physical dependency taxonomy of classes that represent of the laws of classical physics that are the “rules” by which physical properties of physical entities change during occurrences of physical processes. For example, the fluid analog of Ohm’s law (as for electric currents) is used to describe how a blood flow rate depends on a blood pressure gradient. Hooke’s law (as in elastic deformations of springs) is used to describe how an increase in vascular volume increases blood pressure. We classify such dependencies according to the flow, transformation, and storage of thermodynamic energy that occurs during processes governed by the dependencies. Conclusions We have developed the OPB and annotation methods to represent the meaning—the biophysical semantics—of the mathematical statements of physiological analysis and the biophysical content of models and datasets. Here we describe and discuss our approach to an ontological representation of physical laws (as dependencies) and properties as encoded for the mathematical analysis of biophysical processes. PMID:24295137

  19. Method for biological purification

    Science.gov (United States)

    Lucido, John A.; Keenan, Daniel; Premuzic, Eugene T.; Lin, Mow S.; Shelenkova, Ludmila

    2001-03-27

    An apparatus is disclosed for containing a microorganism culture in an active exponential growth and delivering a supply of microorganisms to an environment containing wastes for bio-augmenting the biodegradation of the wastes. The apparatus comprises a bioreactor and an operably connected controller. The bioreactor has a bioreactor chamber for containing a supply of microorganisms, a second chamber for containing a supply of water and inorganic nutrients, and a third chamber for containing a supply of organic nutrients. The bioreactor is operably connected to the controller in which a first pump is operably connected in fluid communication between the bioreactor chamber and the second chamber and third chamber, and a second pump is operably connected in fluid communication between the bioreactor chamber and the environment containing wastes to be biodegraded. The controller further includes a timer and regulator operably connected to the first and second pumps to effectively maintain the microorganisms in exponential growth in the bioreactor chamber and to deliver microorganisms to an environment to be treated. Also, disclosed is a method for bio-augmenting the biodegradation of wastes.

  20. Intermediate Physics for Medicine and Biology

    CERN Document Server

    Hobbie, Russell K

    2007-01-01

    Intended for advanced undergraduate and beginning graduate students in biophysics, physiology, medical physics, cell biology, and biomedical engineering, this wide-ranging text bridges the gap between introductory physics and its application to the life and biomedical sciences. This extensively revised and updated fourth edition reflects new developments at the burgeoning interface between physics and biomedicine. Among the many topics treated are: forces in the skeletal system; fluid flow, with examples from the circulatory system; the logistic equation; scaling; transport of neutral particles by diffusion and by solvent drag; membranes and osmosis; equipartition of energy in statistical mechanics; the chemical potential and free energy; biological magnetic fields; membranes and gated channels in membranes; linear and nonlinear feedback systems; nonlinear phenomena, including biological clocks and chaotic behavior; signal analysis, noise and stochastic resonance detection of weak signals; image formation and...

  1. Biological dosimetry - Dose estimation method using biomakers

    International Nuclear Information System (INIS)

    The individual radiation dose estimation is an important step in the radiation risk assessment. In case of radiation incident or radiation accident, sometime, physical dosimetry method can not be used for calculating the individual radiation dose, the other complement method such as biological dosimetry is very necessary. This method is based on the quantitative specific biomarkers induced by ionizing radiation, such as dicentric chromosomes, translocations, micronuclei... in human peripheral blood lymphocytes. The basis of the biological dosimetry method is the close relationship between the biomarkers and absorbed dose or dose rate; the effects of in vitro and in vivo are similar, so it is able to generate the calibration dose-effect curve in vitro for in vivo assessment. Possibilities and perspectives for performing biological dosimetry method in radiation protection area are presented in this report. (author)

  2. Bridging physics and biology teaching through modeling

    Science.gov (United States)

    Hoskinson, Anne-Marie; Couch, Brian A.; Zwickl, Benjamin M.; Hinko, Kathleen A.; Caballero, Marcos D.

    2014-05-01

    As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life science majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both sciences that rely on observations and measurements to construct models of the natural world. In this article, we propose that efforts to bridge the teaching of these two disciplines must emphasize shared scientific practices, particularly scientific modeling. We define modeling using language common to both disciplines and highlight how an understanding of the modeling process can help reconcile apparent differences between the teaching of physics and biology. We elaborate on how models can be used for explanatory, predictive, and functional purposes and present common models from each discipline demonstrating key modeling principles. By framing interdisciplinary teaching in the context of modeling, we aim to bridge physics and biology teaching and to equip students with modeling competencies applicable in any scientific discipline.

  3. Physical biology of human brain development

    OpenAIRE

    Silvia eBudday; Paul eSteinmann; Ellen eKuhl

    2015-01-01

    Neurodevelopment is a complex, dynamic process that involves a precisely orchestrated sequence of genetic, environmental, biochemical, and physical events. Developmental biology and genetics have shaped our understanding of the molecular and cellular mechanisms during neurodevelopment. Recent studies suggest that physical forces play a central role in translating these cellular mechanisms into the complex surface morphology of the human brain. However, the precise impact of neuronal different...

  4. Physical biology of human brain development

    Directory of Open Access Journals (Sweden)

    Silvia eBudday

    2015-07-01

    Full Text Available Neurodevelopment is a complex, dynamic process that involves a precisely orchestrated sequence of genetic, environmental, biochemical, and physical events. Developmental biology and genetics have shaped our understanding of the molecular and cellular mechanisms during neurodevelopment. Recent studies suggest that physical forces play a central role in translating these cellular mechanisms into the complex surface morphology of the human brain. However, the precise impact of neuronal differentiation, migration, and connection on the physical forces during cortical folding remains unknown. Here we review the cellular mechanisms of neurodevelopment with a view towards surface morphogenesis, pattern selection, and evolution of shape. We revisit cortical folding as the instability problem of constrained differential growth in a multi-layered system. To identify the contributing factors of differential growth, we map out the timeline of neurodevelopment in humans and highlight the cellular events associated with extreme radial and tangential expansion. We demonstrate how computational modeling of differential growth can bridge the scales-from phenomena on the cellular level towards form and function on the organ level-to make quantitative, personalized predictions. Physics-based models can quantify cortical stresses, identify critical folding conditions, rationalize pattern selection, and predict gyral wavelengths and gyrification indices. We illustrate that physical forces can explain cortical malformations as emergent properties of developmental disorders. Combining biology and physics holds promise to advance our understanding of human brain development and enable early diagnostics of cortical malformations with the ultimate goal to improve treatment of neurodevelopmental disorders including epilepsy, autism spectrum disorders, and schizophrenia.

  5. Pragmatic information in biology and physics.

    Science.gov (United States)

    Roederer, Juan G

    2016-03-13

    I will show how an objective definition of the concept of information and the consideration of recent results about information processing in the human brain help clarify some fundamental aspects of physics and biology. Rather than attempting to define information ab initio, I introduce the concept of interaction between material bodies as a primary concept. Two distinct categories can be identified: (i) interactions which can always be reduced to a superposition of physical interactions (forces) between elementary constituents; and (ii) interactions between complex bodies which cannot be expressed as a superposition of interactions between parts, and in which patterns and forms (in space and/or time) play the determining role. Pragmatic information is then defined as the link between a given pattern and the ensuing pattern-specific change. I will show that pragmatic information is a biological concept; it plays no active role in the purely physical domain-it only does so when a living organism intervenes. The consequences for physics (including foundations of quantum mechanics) and biology (including brain function) will be discussed. This will include speculations about three fundamental transitions, from the quantum to the classical domain, from natural inanimate to living systems, and from subhuman to human brain information-processing operations, introduced here in their direct connection with the concept of pragmatic information. PMID:26857662

  6. BOOK REVIEW Handbook of Physics in Medicine and Biology Handbook of Physics in Medicine and Biology

    Science.gov (United States)

    Tabakov, Slavik

    2010-11-01

    ; artificial muscle; cardiovascular system; control of cardiac output and arterial blood pressure regulation; fluid dynamics of the cardiovascular system; fluid dynamics; modeling and simulation of the cardiovascular system to determine work using bond graphs; anatomy and physics of respiration. The diagrams and data in this section could be used as reference material, but some chapters (such as that on the cardiovascular system) again take the form of physiological explanations. The best chapters in this section are on fluid dynamics and modeling. The fourth section (about 30 pages) includes two chapters on electrodes and recording of bioelectrical signals: theory and practice. Both chapters deal with electrodes and are well written and illustrated reference materials. This section could have been larger but the equipment associated with bioelectrical signals (such as ECG and EEG) is described in the next section. The fifth section (about 210 pages) includes 19 chapters on medical sensing and imaging; electrocardiogram: electrical information retrieval and diagnostics from the beating heart; electroencephalography: basic concepts and brain applications; bioelectric impedance analysis; x-ray and computed tomography; confocal microscopy; magnetic resonance imaging; positron emission tomography; in vivo fluorescence imaging and spectroscopy; optical coherence tomography; ultrasonic imaging; near-field imaging; atomic force microscopy; scanning ion conductance microscopy; quantitative thermographic imaging; intracoronary thermography; schlieren imaging: optical techniques to visualize thermal interactions with biological tissues; helium ion microscopy; electron microscopy: SEM/TEM. This is by far the largest section covering various methods and medical equipment and the variation in emphasis/quality is more prominent. The chapters on ECG and EEG are again more physiological with less physics, but the chapter on bioelectric impedance analysis is a good interdisciplinary article

  7. Physical Properties of Biological Entities: An Introduction to the Ontology of Physics for Biology

    OpenAIRE

    Cook, Daniel L.; Bookstein, Fred L.; John H Gennari

    2011-01-01

    As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities—molecules, cells, organs—are well-established, there are no principled ontologies of physical properties—energies, volumes, flow rates—of those entities. In this paper, we introduce the Ontology of Physics for Biology (OPB), a ...

  8. Method to detect biological particles

    International Nuclear Information System (INIS)

    A medical-diagnostic method to detect immunological as well as other specific reactions is described. According to the invention, first reactive particles (e.g. antibodies) are adsorbed on the surface of a solid, non-reactive substrate. The coated substrate is subjected to a solution which one assumes to contain the second biological particles (e.g. antigens) which are specific to the first and form complexes with these. A preferential radioactive labelling (e.g. with iodine 125) of the second biological particle is then directly or indirectly carried out. Clearage follows labelling in order to separate the second biological particles from the first ones. A specific splitting agent can selectively break the bond of both types of particle. The splitting agent solution is finally separated off and its content is investigated for the presence of labelling. (VJ)

  9. Bridging Physics and Biology Using Resistance and Axons

    Science.gov (United States)

    Dyer, Joshua M.

    2014-01-01

    When teaching physics, it is often difficult to get biology-oriented students to see the relevance of physics. A complaint often heard is that biology students are required to take physics for the Medical College Admission Test (MCAT) as part of a "weeding out" process, but that they don't feel like they need physics for biology.…

  10. Physics and Biology Collaborate to Color the World

    OpenAIRE

    Liu, Dennis W. C.

    2013-01-01

    To understand how life works, it is essential to understand physics and chemistry. Physics informs and enlightens biology in myriad dimensions, yet many biology courses proceed with little or no consideration of physical properties or principles. The intersection between physics and biology is explored in this review of online media.

  11. Physical Activity, Physical Performance, and Biological Markers of Health among Sedentary Older Latinos

    OpenAIRE

    Gerardo Moreno; Mangione, Carol M; Pin-Chieh Wang; Laura Trejo; Anthony Butch; Chi-Hong Tseng; Sarkisian, Catherine A.

    2014-01-01

    Background. Physical activity is associated with better physical health, possibly by changing biological markers of health such as waist circumference and inflammation, but these relationships are unclear and even less understood among older Latinos—a group with high rates of sedentary lifestyle. Methods. Participants were 120 sedentary older Latino adults from senior centers. Community-partnered research methods were used to recruit participants. Inflammatory (C-reactive protein) and metabol...

  12. Physical properties of biological entities: an introduction to the ontology of physics for biology.

    Directory of Open Access Journals (Sweden)

    Daniel L Cook

    Full Text Available As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities-molecules, cells, organs-are well-established, there are no principled ontologies of physical properties-energies, volumes, flow rates-of those entities. In this paper, we introduce the Ontology of Physics for Biology (OPB, a reference ontology of classical physics designed for annotating biophysical content of growing repositories of biomedical datasets and analytical models. The OPB's semantic framework, traceable to James Clerk Maxwell, encompasses modern theories of system dynamics and thermodynamics, and is implemented as a computational ontology that references available upper ontologies. In this paper we focus on the OPB classes that are designed for annotating physical properties encoded in biomedical datasets and computational models, and we discuss how the OPB framework will facilitate biomedical knowledge integration.

  13. Physical properties of biological entities: an introduction to the ontology of physics for biology.

    Science.gov (United States)

    Cook, Daniel L; Bookstein, Fred L; Gennari, John H

    2011-01-01

    As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities-molecules, cells, organs-are well-established, there are no principled ontologies of physical properties-energies, volumes, flow rates-of those entities. In this paper, we introduce the Ontology of Physics for Biology (OPB), a reference ontology of classical physics designed for annotating biophysical content of growing repositories of biomedical datasets and analytical models. The OPB's semantic framework, traceable to James Clerk Maxwell, encompasses modern theories of system dynamics and thermodynamics, and is implemented as a computational ontology that references available upper ontologies. In this paper we focus on the OPB classes that are designed for annotating physical properties encoded in biomedical datasets and computational models, and we discuss how the OPB framework will facilitate biomedical knowledge integration. PMID:22216106

  14. The common extremalities in biology and physics maximum energy dissipation principle in chemistry, biology, physics and evolution

    CERN Document Server

    Moroz, Adam

    2011-01-01

    This book is the first unified systemic description of dissipative phenomena, taking place in biology, and non-dissipative (conservative) phenomena, which is more relevant to physics. Fully updated and revised, this new edition extends our understanding of nonlinear phenomena in biology and physics from the extreme / optimal perspective. The first book to provide understanding of physical phenomena from a biological perspective and biological phenomena from a physical perspectiveDiscusses emerging fields and analysisProvides examples

  15. Radiation physics, biophysics, and radiation biology

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  16. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood ''biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons

  17. Physics and Biology Collaborate to Color the World

    Science.gov (United States)

    Liu, Dennis W. C.

    2013-01-01

    To understand how life works, it is essential to understand physics and chemistry. Most biologists have a clear notion of where chemistry fits into their life sciences research and teaching. Although we are physical beings, physics does not always find a place in the biology curriculum. Physics informs and enlightens biology in myriad dimensions,…

  18. Methods of experimental physics

    CERN Document Server

    Pergament, M I

    2014-01-01

    IntroductionIndirect Data and Inverse ProblemsExperiment and Stochasticity of the Physical WorldGeneral Properties of Measuring-Recording SystemsLinear Measuring-Recording SystemsTransfer Function and Convolution EquationTransfer Ratio, Amplitude-Frequency and Phase-Frequency Characteristics, and Relation Between Input and Output Signals in Fourier SpaceSome ConsequencesDiscretizationCommunication Theory ApproachDetermination of the Measuring-Recording System ParametersStudying Pulse Processes<

  19. Biological Physics : Poincaré seminar

    CERN Document Server

    Bio-physique : séminaire Poincaré

    2011-01-01

    This new volume in the Poincaré Seminar Series, describing recent developments at the interface between physics and biology, is directed towards a broad audience of physicists, biologists, and mathematicians. Both the theoretical and experimental aspects are covered, and particular care is devoted to the pedagogical nature of the presentations. The first survey article, by Jean-Francois Joanny and Jacques Prost, describes the theoretical advances made in the study of "active gels", with applications to liquid crystals and cell motility. Jasper van der Gucht and Cécile Sykes then report on recent advances made with biomimetic model systems in the understanding of cytokinesis. The next article, by Jonathon Howard, presents several molecular models for motor proteins, which are compared with experimental results for kinesin. David Lacoste and Kirone Mallick then show theoretically that similar ratchet models of motor proteins naturally satisfy a fundamental time-reversal symmetry, the Gallavotti-Cohen fluctuat...

  20. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    Research at the Radiological Research Laboratory is a blend of physics, chemistry, and biology, involving research at the basic level with the admixture of a small proportion of pragmatic or applied research in support of radiation protection and/or radiotherapy. Current research topics include: oncogenic transformation assays, mutation studies involving interactions between radiation and environmental contaminants, isolation, characterization and sequencing of a human repair gene, characterization of a dominant transforming gene found in C3H 10T1/2 cells, characterize ab initio the interaction of DNA and radiation, refine estimates of the radiation quality factor Q, a new mechanistic model of oncogenesis showing the role of long-term low dose medium LET radiation, and time dependent modeling of radiation induced chromosome damage and subsequent repair or misrepair

  1. Understanding How Students Use Physical Ideas in Introductory Biology Courses

    OpenAIRE

    Watkins, Jessica; Hall, Kristi; Redish, Edward; Cooke, Todd

    2010-01-01

    The University of Maryland (UMD) Biology Education and Physics Education Research Groups are investigating students' views on the role of physics in introductory biology courses. This paper presents data from an introductory course that addresses the fundamental principles of organismal biology and that incorporates several topics directly related to physics, including thermodynamics, diffusion, and fluid flow. We examine how the instructors use mathematics and physics in this introductory bi...

  2. The universal numbers. From Biology to Physics.

    Science.gov (United States)

    Marchal, Bruno

    2015-12-01

    I will explain how the mathematicians have discovered the universal numbers, or abstract computer, and I will explain some abstract biology, mainly self-reproduction and embryogenesis. Then I will explain how and why, and in which sense, some of those numbers can dream and why their dreams can glue together and must, when we assume computationalism in cognitive science, generate a phenomenological physics, as part of a larger phenomenological theology (in the sense of the greek theologians). The title should have been "From Biology to Physics, through the Phenomenological Theology of the Universal Numbers", if that was not too long for a title. The theology will consist mainly, like in some (neo)platonist greek-indian-chinese tradition, in the truth about numbers' relative relations, with each others, and with themselves. The main difference between Aristotle and Plato is that Aristotle (especially in its common and modern christian interpretation) makes reality WYSIWYG (What you see is what you get: reality is what we observe, measure, i.e. the natural material physical science) where for Plato and the (rational) mystics, what we see might be only the shadow or the border of something else, which might be non physical (mathematical, arithmetical, theological, …). Since Gödel, we know that Truth, even just the Arithmetical Truth, is vastly bigger than what the machine can rationally justify. Yet, with Church's thesis, and the mechanizability of the diagonalizations involved, machines can apprehend this and can justify their limitations, and get some sense of what might be true beyond what they can prove or justify rationally. Indeed, the incompleteness phenomenon introduces a gap between what is provable by some machine and what is true about that machine, and, as Gödel saw already in 1931, the existence of that gap is accessible to the machine itself, once it is has enough provability abilities. Incompleteness separates truth and provable, and machines can

  3. Probabilistic methods for physics

    International Nuclear Information System (INIS)

    We present an asymptotic method giving a probability of presence of the iterated spots of Rd by a polynomial function f. We use the well-known Perron Frobenius operator (PF) that lets certain sets and measure invariant by f. Probabilistic solutions can exist for the deterministic iteration. If the theoretical result is already known, here we quantify these probabilities. This approach seems interesting to use for computing situations when the deterministic methods don't run. Among the examined applications, are asymptotic solutions of Lorenz, Navier-Stokes or Hamilton's equations. In this approach, linearity induces many difficult problems, all of whom we have not yet resolved.

  4. A random walk in physical biology

    Science.gov (United States)

    Peterson, Eric Lee

    Biology as a scientific discipline is becoming evermore quantitative as tools become available to probe living systems on every scale from the macro to the micro and now even to the nanoscale. In quantitative biology the challenge is to understand the living world in an in vivo context, where it is often difficult for simple theoretical models to connect with the full richness and complexity of the observed data. Computational models and simulations offer a way to bridge the gap between simple theoretical models and real biological systems; towards that aspiration are presented in this thesis three case studies in applying computational models that may give insight into native biological structures.The first is concerned with soluble proteins; proteins, like DNA, are linear polymers written in a twenty-letter "language" of amino acids. Despite the astronomical number of possible proteins sequences, a great amount of similarity is observed among the folded structures of globular proteins. One useful way of discovering similar sequences is to align their sequences, as done e.g. by the popular BLAST program. By clustering together amino acids and reducing the alphabet that proteins are written in to fewer than twenty letters, we find that pairwise sequence alignments are actually more sensitive to proteins with similar structures.The second case study is concerned with the measurement of forces applied to a membrane. We demonstrate a general method for extracting the forces applied to a fluid lipid bilayer of arbitrary shape and show that the subpiconewton forces applied by optical tweezers to vesicles can be accurately measured in this way.In the third and final case study we examine the forces between proteins in a lipid bilayer membrane. Due to the bending of the membrane surrounding them, such proteins feel mutually attractive forces which can help them to self-organize and act in concert. These finding are relevant at the areal densities estimated for membrane

  5. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    An important event of the year was the designation of our Laboratory as a Center for Radiological Research by the Dean of the Faculty of Medicine and Vice-President for Health Sciences. Center status acknowledges the size and importance of the research efforts in this area, and allows a greater measure of independence in administrative matters. While the name has changed from a Laboratory to a Center within the Medical School, the mission and charge remain the same. The efforts of the Center are a multidisciplinary mix of physics, chemistry, and biology, mostly at a basic level, with the admixture of a small proportion of pragmatic or applied research in support of radiation protection or radiation therapy. About a quarter of our funding, mostly individual research awards, could be regarded as in direct support of radiotherapy, with the remainder (an NCI program project grant and DOE grants) being in support of research addressing more basic issues. An important effort currently underway concerns ab-initio calculations of the dielectric response function of condensed water. This investigation has received the coveted designation, ''Grand Challenge Project,'' awarded by DOE to research work which represents ''distinct advance on a major scientific or engineering problem that is broadly recognized as important within the mission of the Department.''

  6. Comparison in the determination of absorbed dose by biological and physical methods to patients in treatment of cardiac intervention; Comparacion en la determinacion de dosis absorbida por metodos biologicos y fisicos a pacientes en tratamiento de intervencionismo cardiaco

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Arceo M, C., E-mail: citlali.guerrero@inin.gob.mx [ININ, Departamento de Biologia, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    The use of less invasive procedures, lower risk and quick recovery as cardiac intervention have proven to be an efficient alternative to reestablish the correct bloodstream of the patient. In this case the patient is subjected to values of absorbed dose above to which is subjected in a study with X-rays for medical diagnosis, and this can cause radiation injuries to the skin. The target organ, in this case can be exposed to doses of 2 Gy above. Different methods to estimate the dose were use, physical by Radiochromic film, as biological by dicentric analysis. Both methods provided additional information demonstrating thus the risk in the target organ and the patient. The most reliable biological indicator of exposure to ionizing radiation is the study of chromosomal aberrations, specifically dicentric in human lymphocytes. This test allowed establishing the exposure dose depending of the damage. (Author)

  7. Computational Methods in Plasma Physics

    CERN Document Server

    Jardin, Stephen

    2010-01-01

    Assuming no prior knowledge of plasma physics or numerical methods, Computational Methods in Plasma Physics covers the computational mathematics and techniques needed to simulate magnetically confined plasmas in modern magnetic fusion experiments and future magnetic fusion reactors. Largely self-contained, the text presents the basic concepts necessary for the numerical solution of partial differential equations. Along with discussing numerical stability and accuracy, the author explores many of the algorithms used today in enough depth so that readers can analyze their stability, efficiency,

  8. Monte Carlo Methods in Physics

    International Nuclear Information System (INIS)

    Method of Monte Carlo integration is reviewed briefly and some of its applications in physics are explained. A numerical experiment on random generators used in the monte Carlo techniques is carried out to show the behavior of the randomness of various methods in generating them. To account for the weight function involved in the Monte Carlo, the metropolis method is used. From the results of the experiment, one can see that there is no regular patterns of the numbers generated, showing that the program generators are reasonably good, while the experimental results, shows a statistical distribution obeying statistical distribution law. Further some applications of the Monte Carlo methods in physics are given. The choice of physical problems are such that the models have available solutions either in exact or approximate values, in which comparisons can be mode, with the calculations using the Monte Carlo method. Comparison show that for the models to be considered, good agreement have been obtained

  9. Nanodosimetry, from radiation physics to radiation biology.

    Science.gov (United States)

    Grosswendt, B

    2005-01-01

    In view of the fact that early damage to genes and cells by ionising radiation starts with the early damage to segments of the DNA, it is a great challenge to radiation research to describe the general behaviour of ionising radiation in nanometric target volumes (nanodosimetry). After summarising basic aspects of nanodosimetry, an overview is given about its present state. As far as experimental procedures are concerned, main emphasis is laid on single-ion counting and single-electron counting methods, which use millimetric target volumes filled with a low-pressure gas to simulate nanometric target volumes at unit density. Afterwards, physical principles are discussed, which can be used to convert experimental ionisation cluster-size distributions into those caused by ionising radiation in liquid water. In the final section, possibilities are analysed of how to relate parameters derived from the probability of cluster-size formation in liquid water to parameters derived from radiobiological experiments. PMID:16381675

  10. Nanodosimetry, from radiation physics to radiation biology

    International Nuclear Information System (INIS)

    In view of the fact that early damage to genes and cells by ionising radiation starts with the early damage to segments of the DNA, it is a great challenge to radiation research to describe the general behaviour of ionising radiation in nano-metric target volumes (nanodosimetry). After summarising basic aspects of nanodosimetry, an overview is given about its present state. As far as experimental procedures are concerned, main emphasis is laid on single-ion counting and single-electron counting methods, which use millimetric target volumes filled with a low-pressure gas to simulate nano-metric target volumes at unit density. Afterwards, physical principles are discussed, which can be used to convert experimental ionisation cluster-size distributions into those caused by ionising radiation in liquid water. In the final section, possibilities are analysed of how to relate parameters derived from the probability of cluster-size formation in liquid water to parameters derived from radiobiological experiments. (authors)

  11. Statistical methods for physical science

    CERN Document Server

    Stanford, John L

    1994-01-01

    This volume of Methods of Experimental Physics provides an extensive introduction to probability and statistics in many areas of the physical sciences, with an emphasis on the emerging area of spatial statistics. The scope of topics covered is wide-ranging-the text discusses a variety of the most commonly used classical methods and addresses newer methods that are applicable or potentially important. The chapter authors motivate readers with their insightful discussions, augmenting their material withKey Features* Examines basic probability, including coverage of standard distributions, time s

  12. Psychological Profiles of Physical and Biological Science Choosers.

    Science.gov (United States)

    Collings, John; Smithers, Alan

    1983-01-01

    Investigated male/female sixth-formers studying physical and biological science A-level courses, examining cognitive style, convergent/divergent thinking, career plans, and other characteristics. Differences between biology/physics students tend to be of the same kind as those between scientists as a whole compared to nonscientists. (JN)

  13. The Physics of Proteins An Introduction to Biological Physics and Molecular Biophysics

    CERN Document Server

    Frauenfelder, Hans; Chan, Winnie S

    2010-01-01

    Physics and the life sciences have established new connections within the past few decades, resulting in biological physics as an established subfield with strong groups working in many physics departments. These interactions between physics and biology form a two-way street with physics providing new tools and concepts for understanding life, while biological systems can yield new insights into the physics of complex systems. To address the challenges of this interdisciplinary area, The Physics of Proteins: An Introduction to Biological Physics and Molecular Biophysics is divided into three interconnected sections. In Parts I and II, early chapters introduce the terminology and describe the main biological systems that physicists will encounter. Similarities between biomolecules, glasses, and solids are stressed with an emphasis on the fundamental concepts of living systems. The central section (Parts III and IV) delves into the dynamics of complex systems. A main theme is the realization that biological sys...

  14. Designing an Introductory Physics Course for Biological Science Students

    Science.gov (United States)

    Heller, Kenneth

    2009-05-01

    For the past four years the School of Physics and Astronomy at the University of Minnesota has been revising its Introductory Physics Course specifically targeted to biological science and pre-medical students. The course design process includes determining the reasons that introductory physics is required by the biology faculty and determining how or if to satisfy their goals. The resulting course must substantially satisfy the goals of the biology faculty, be an introductory physics course that stresses the application of fundamental principles and relates them to complex situations typical in biology, be of interest to beginning biology students, and be teachable by ordinary physics professors. The design process for the content and the pedagogy of the course will be described as will the resulting course structure. Student performance measures for the revised course will also be given.

  15. Complex network problems in physics, computer science and biology

    Science.gov (United States)

    Cojocaru, Radu Ionut

    There is a close relation between physics and mathematics and the exchange of ideas between these two sciences are well established. However until few years ago there was no such a close relation between physics and computer science. Even more, only recently biologists started to use methods and tools from statistical physics in order to study the behavior of complex system. In this thesis we concentrate on applying and analyzing several methods borrowed from computer science to biology and also we use methods from statistical physics in solving hard problems from computer science. In recent years physicists have been interested in studying the behavior of complex networks. Physics is an experimental science in which theoretical predictions are compared to experiments. In this definition, the term prediction plays a very important role: although the system is complex, it is still possible to get predictions for its behavior, but these predictions are of a probabilistic nature. Spin glasses, lattice gases or the Potts model are a few examples of complex systems in physics. Spin glasses and many frustrated antiferromagnets map exactly to computer science problems in the NP-hard class defined in Chapter 1. In Chapter 1 we discuss a common result from artificial intelligence (AI) which shows that there are some problems which are NP-complete, with the implication that these problems are difficult to solve. We introduce a few well known hard problems from computer science (Satisfiability, Coloring, Vertex Cover together with Maximum Independent Set and Number Partitioning) and then discuss their mapping to problems from physics. In Chapter 2 we provide a short review of combinatorial optimization algorithms and their applications to ground state problems in disordered systems. We discuss the cavity method initially developed for studying the Sherrington-Kirkpatrick model of spin glasses. We extend this model to the study of a specific case of spin glass on the Bethe

  16. Qualitative methods in theoretical physics

    CERN Document Server

    Maslov, Dmitrii

    2016-01-01

    This book comprises a set of tools which allow researchers and students to arrive at a qualitatively correct answer without undertaking lengthy calculations. In general, Qualitative Methods in Theoretical Physics is about combining approximate mathematical methods with fundamental principles of physics: conservation laws and symmetries. Readers will learn how to simplify problems, how to estimate results, and how to apply symmetry arguments and conduct dimensional analysis. A comprehensive problem set is included. The book will appeal to a wide range of students and researchers.

  17. Dose estimation by biological methods

    International Nuclear Information System (INIS)

    The human being is exposed to strong artificial radiation sources, mainly of two forms: the first is referred to the occupationally exposed personnel (POE) and the second, to the persons that require radiological treatment. A third form less common is by accidents. In all these conditions it is very important to estimate the absorbed dose. The classical biological dosimetry is based in the dicentric analysis. The present work is part of researches to the process to validate the In situ Fluorescent hybridation (FISH) technique which allows to analyse the aberrations on the chromosomes. (Author)

  18. Mathematical methods in biology and neurobiology

    CERN Document Server

    Jost, Jürgen

    2014-01-01

    Mathematical models can be used to meet many of the challenges and opportunities offered by modern biology. The description of biological phenomena requires a range of mathematical theories. This is the case particularly for the emerging field of systems biology. Mathematical Methods in Biology and Neurobiology introduces and develops these mathematical structures and methods in a systematic manner. It studies:   • discrete structures and graph theory • stochastic processes • dynamical systems and partial differential equations • optimization and the calculus of variations.   The biological applications range from molecular to evolutionary and ecological levels, for example:   • cellular reaction kinetics and gene regulation • biological pattern formation and chemotaxis • the biophysics and dynamics of neurons • the coding of information in neuronal systems • phylogenetic tree reconstruction • branching processes and population genetics • optimal resource allocation • sexual recombi...

  19. From Gene to Protein: A 3-Week Intensive Course in Molecular Biology for Physical Scientists

    Science.gov (United States)

    Nadeau, Jay L.

    2009-01-01

    This article describes a 3-week intensive molecular biology methods course based upon fluorescent proteins, which is successfully taught at the McGill University to advanced undergraduates and graduates in physics, chemical engineering, biomedical engineering, and medicine. No previous knowledge of biological terminology or methods is expected, so…

  20. Nuclear methods in medical physics

    International Nuclear Information System (INIS)

    A common ground for both, reactor and medical physics is a demand for high accuracy of particle transport calculations. In reactor physics, safe operation of nuclear power plants has been asking for high accuracy of calculation methods. Similarly, dose calculation in radiation therapy for cancer has been requesting high accuracy of transport methods to ensure adequate dosimetry. Common to both problems has always been a compromise between achievable accuracy and available computer power leading into a variety of calculation methods developed over the decades. On the other hand, differences of subjects (nuclear reactor vs. humans) and radiation types (neutron/photon vs. photon/electron or ions) are calling for very field-specific approach. Nevertheless, it is not uncommon to see drift of researches from one field to another. Several examples from both fields will be given with the aim to compare the problems, indicating their similarities and discussing their differences. As examples of reactor physics applications, both deterministic and Monte Carlo calculations will be presented for flux distributions of the VENUS and TRIGA Mark II benchmark. These problems will be paralleled to medical physics applications in linear accelerator radiation field determination and dose distribution calculations. Applicability of the adjoint/forward transport will be discussed in the light of both transport problems. Boron neutron capture therapy (BNCT) as an example of the close collaboration between the fields will be presented. At last, several other examples from medical physics, which can and cannot find corresponding problems in reactor physics, will be discussed (e.g., beam optimisation in inverse treatment planning, imaging applications). (author)

  1. Coupled model of physical and biological processes affecting maize pollination

    Science.gov (United States)

    Arritt, R.; Westgate, M.; Riese, J.; Falk, M.; Takle, E.

    2003-04-01

    Controversy over the use of genetically modified (GM) crops has led to increased interest in evaluating and controlling the potential for inadvertent outcrossing in open-pollinated crops such as maize. In response to this problem we have developed a Lagrangian model of pollen dispersion as a component of a coupled end-to-end (anther to ear) physical-biological model of maize pollination. The Lagrangian method is adopted because of its generality and flexibility: first, the method readily accommodates flow fields of arbitrary complexity; second, each element of the material being transported can be identified by its source, time of release, or other properties of interest. The latter allows pollen viability to be estimated as a function of such factors as travel time, temperature, and relative humidity, so that the physical effects of airflow and turbulence on pollen dispersion can be considered together with the biological aspects of pollen release and viability. Predicted dispersion of pollen compares well both to observations and to results from a simpler Gaussian plume model. Ability of the Lagrangian model to handle complex air flows is demonstrated by application to pollen dispersion in the vicinity of an agricultural shelter belt. We also show results indicating that pollen viability can be quantified by an "aging function" that accounts for temperature, humidity, and time of exposure.

  2. Physical and biological factors determining the effective proton range

    Energy Technology Data Exchange (ETDEWEB)

    Grün, Rebecca [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390 (Germany); Medical Faculty of Philipps-University Marburg, Marburg 35032 (Germany); Friedrich, Thomas; Krämer, Michael; Scholz, Michael [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Zink, Klemens [Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany); Durante, Marco [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291, Germany and Department of Condensed Matter Physics, Darmstadt University of Technology, Darmstadt 64289 (Germany); Engenhart-Cabillic, Rita [Medical Faculty of Philipps-University Marburg, Marburg 35032, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)

    2013-11-15

    Purpose: Proton radiotherapy is rapidly becoming a standard treatment option for cancer. However, even though experimental data show an increase of the relative biological effectiveness (RBE) with depth, particularly at the distal end of the treatment field, a generic RBE of 1.1 is currently used in proton radiotherapy. This discrepancy might affect the effective penetration depth of the proton beam and thus the dose to the surrounding tissue and organs at risk. The purpose of this study was thus to analyze the impact of a tissue and dose dependent RBE of protons on the effective range of the proton beam in comparison to the range based on a generic RBE of 1.1.Methods: Factors influencing the biologically effective proton range were systematically analyzed by means of treatment planning studies using the Local Effect Model (LEM IV) and the treatment planning software TRiP98. Special emphasis was put on the comparison of passive and active range modulation techniques.Results: Beam energy, tissue type, and dose level significantly affected the biological extension of the treatment field at the distal edge. Up to 4 mm increased penetration depth as compared to the depth based on a constant RBE of 1.1. The extension of the biologically effective range strongly depends on the initial proton energy used for the most distal layer of the field and correlates with the width of the distal penumbra. Thus, the range extension, in general, was more pronounced for passive as compared to active range modulation systems, whereas the maximum RBE was higher for active systems.Conclusions: The analysis showed that the physical characteristics of the proton beam in terms of the width of the distal penumbra have a great impact on the RBE gradient and thus also the biologically effective penetration depth of the beam.

  3. Radiation physics, biophysics, and radiation biology

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.

    1992-05-01

    The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent.

  4. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent

  5. Stochastic Physics, Complex Systems and Biology

    CERN Document Server

    Qian, Hong

    2012-01-01

    In complex systems, the interplay between nonlinear and stochastic dynamics gives rise to an evolution process in Darwinian sense with punctuated equilibrium, random "mutations" and "adaptations". The emergent discrete states in such a system, i.e., attractors, have natural robustness against both internal and external perturbations. Epigenetic states of a biological cell, a mesoscopic nonlinear stochastic open biochemical system, could be understood through such a framework.

  6. Physical and biological characterization of a seawater ultraviolet radiation sterilizer

    International Nuclear Information System (INIS)

    The physical and biological characterization of a seawater ultraviolet (UV) sterilizer is described. The physical characterization was performed using radiochromic dye films by evaluating the uniformity of the radiant exposure along each lamp, the effect of the radiation from one lamp on the array of adjacent lamps, and by measuring the UV radiation absorption of seawater with respect to distilled water. The biological characterization was performed by measuring the amount of reduction of bacteria in stored seawater after different filtration and UV treatments. Among the filtration methods tested, differential filtration (5, 3 and 0.45 μm filters connected in series) caused the highest bacterial reduction factor of 60%. UV radiant exposures of 212, 424, 636 and 848 J m-2 yielded bacteria reduction factors of 99.86, 99.969, 99.997 and 100%, respectively, for populations of Vibrio and Pseudomonas bacteria present in stored seawater. It is concluded that the system is useful for water disinfection when 1, 2 or 3 lamps are on; when 4 lamps are used the treated water becomes sterile. (author)

  7. Bridging Physics and Biology Using Resistance and Axons

    Science.gov (United States)

    Dyer, Joshua M.

    2014-11-01

    When teaching physics, it is often difficult to get biology-oriented students to see the relevance of physics.1 A complaint often heard is that biology students are required to take physics for the Medical College Admission Test (MCAT) as part of a "weeding out" process, but that they don't feel like they need physics for biology. Despite this impression held by students, there have been calls for better physics education for future physicians and life scientists.2,3 Research is being performed to improve physics classes and labs by linking topics in biology and physics.4,5 Described here is a laboratory experiment covering the topics of resistance of materials and circuits/Kirchhoff's laws in a biology context with their direct application to neurons, axons, and electrical impulse transmission within animals. This experiment will also demonstrate the mechanism believed to cause multiple sclerosis. The apparatus was designed with low-cost and readily available materials in mind.

  8. Robotics and Biology: Lets get Physical

    Science.gov (United States)

    Choset, Howie

    Our research group investigates the core fundamentals of locomotion as it exists in biology and as it applies to locomoting robotic systems. Initially, our work advanced techniques found in geometric mechanics to design cyclic controllers, often called gaits, for snake robots, highly articulated mechanisms that can thread through tightly packed spaces to access locations people cannot. We had considerable success in designing snake robot gaits, but found our systems stymied in terrains characterized by sandy substrates. Sandy terrains and other granular media pose a challenge to snake robots because it is unclear how the mechanism interacts with environment: we cannot simply assume the robot is on hard-ground nor in a fluid. Simulating granular interactions can prove to be computationally intractable for real-time use on the robots. Therefore, we developed experimental tools that allowed us to sieve out models of the locomoting systems operating on granular media. We were then able to bring these models into harmony with the elegant formulation of our geometric mechanics approach. This allowed us to derive adaptive controllers for our snake robots in sandy terrains, and enabled us to gain deeper insight into of how biological systems move over similar terrains as well.

  9. Nuclear Physics in a biological context

    Science.gov (United States)

    Discher, Dennis

    2012-02-01

    A solid tissue can be soft like fat or brain, stiff like striated muscle and heart, or rigid like bone -- and of course every cell has a nucleus that contributes in some way small or large to tissue mechanics. Indeed, nuclei generally exhibit rheology and plasticity that reflects both the chromatin and the nuclear envelope proteins called lamins, all of which change in differentiation. Profiling of tissue nuclei shows that the nuclear intermediate filament protein Lamin-A/C varies over 30-fold between adult tissues and scales strongly with micro-elasticity of tissue, while other nuclear envelope components such as Lamin-B exhibit small variations. Lamin-A/C has been implicated in aging syndromes that affect muscle and fat but not brain, and we find nuclei in brain-derived cells are indeed dominated by Lamin-B and are much softer than nuclei derived from muscle cells with predominantly Lamin-A/C. In vitro, matrix elasticity can affect expression of nuclear envelope components in adult stem cells, and major changes in Lamin-A/C are indeed shown to direct lineage with lower levels favoring soft tissue and higher levels promoting rigid tissue lineage. Further molecular studies provide evidence that the nucleus transduces physical stress. References: (1) J.D. Pajerowski, K.N. Dahl, F.L. Zhong, P.J. Sammak, and D.E. Discher. Physical plasticity of the nucleus in stem cell differentiation. PNAS 104: 15619-15624 (2007). (2) A. Buxboim, I. Ivanova, and D.E. Discher. Matrix Elasticity, Cytoskeletal Forces, and Physics of the Nucleus: how deeply do cells `feel' outside and in? Journal of Cell Science 123: 297-308 (2010).

  10. Physical acoustics principles and methods

    CERN Document Server

    Mason, Warren P

    1964-01-01

    Physical Acoustics: Principles and Methods, Volume l-Part A focuses on high frequency sound waves in gases, liquids, and solids that have been proven as powerful tools in analyzing the molecular, defect, domain wall, and other types of motions. The selection first tackles wave propagation in fluids and normal solids and guided wave propagation in elongated cylinders and plates. Discussions focus on fundamentals of continuum mechanics; small-amplitude waves in a linear viscoelastic medium; representation of oscillations and waves; and special effects associated with guided elastic waves in plat

  11. The 'atom-splitting' moment of synthetic biology: Nuclear physics and synthetic biology share common features

    OpenAIRE

    Valentine, Alex J; Kleinert, Aleysia; Verdier, Jerome

    2012-01-01

    Synthetic biology and nuclear physics share many commonalities in terms of public perception and funding. Synthetic biologists could learn valuable lessons from the history of the atomic bomb and nuclear power.

  12. Introductory physics in biological context: An approach to improve introductory physics for life science students

    Science.gov (United States)

    Crouch, Catherine H.; Heller, Kenneth

    2014-05-01

    We describe restructuring the introductory physics for life science students (IPLS) course to better support these students in using physics to understand their chosen fields. Our courses teach physics using biologically rich contexts. Specifically, we use examples in which fundamental physics contributes significantly to understanding a biological system to make explicit the value of physics to the life sciences. This requires selecting the course content to reflect the topics most relevant to biology while maintaining the fundamental disciplinary structure of physics. In addition to stressing the importance of the fundamental principles of physics, an important goal is developing students' quantitative and problem solving skills. Our guiding pedagogical framework is the cognitive apprenticeship model, in which learning occurs most effectively when students can articulate why what they are learning matters to them. In this article, we describe our courses, summarize initial assessment data, and identify needs for future research.

  13. Sarcopenia as the Biological Substrate of Physical Frailty.

    Science.gov (United States)

    Landi, Francesco; Calvani, Riccardo; Cesari, Matteo; Tosato, Matteo; Martone, Anna Maria; Bernabei, Roberto; Onder, Graziano; Marzetti, Emanuele

    2015-08-01

    Physical function decreases with aging, which may result in adverse outcomes (eg, disability, loss of independence, institutionalization, death). Physical function impairment is a common trait of frailty and sarcopenia. These two conditions, albeit highly common, have not yet received a unique operational definition, which has impeded their implementation in standard practice. Here, we introduce a conceptual model in which sarcopenia is proposed as the biological substrate and the pathway whereby the consequences of physical frailty develop. This conceptualization may open new venues for the design of interventions against physical frailty and promote the translation of findings to the clinical arena. PMID:26195096

  14. Physics in Brazil in the next decade: atomic, molecular and optical physics, biological, chemical and medical physics, physics teaching and plasma physics

    International Nuclear Information System (INIS)

    This is an overview of physics in Brazil in the next decade. It is specially concerned with atomic, molecular and optical physics, biological chemical and medical physics, and also teaching of physics and plasma physics. It presents the main research groups in Brazil in the above mentioned areas. It talks as well, about financing new projects and the costs involved to improve these areas. (A.C.A.S.)

  15. PREFACE: Physics and biology of neurodegenerative diseases Physics and biology of neurodegenerative diseases

    Science.gov (United States)

    Pastore, Annalisa

    2012-06-01

    , about 15 years after the original reports, it is clear that amyloids are special structures that occur in nature under several different guises, some good, some evil [3]. The number of diseases associated with misfolding and fibrillogenesis has steadily increased. Examples of fairly common pathologies associated with fibre formation include Alzheimer's disease (currently one of the major threats for human health in our increasingly aging world), Parkinson's disease and several rare, but not less severe, pathologies. On the other hand, it is also clear that amyloid formation is a convenient mechanism for storing peptides and/or proteins in a compact and resistant way. The number of organisms/tissues in which amyloid deposits are found is thus increasing. It is also not too far-fetched to expect that the mechanical properties of amyloids could be used in biotechnology to design new materials. Because of the importance of this topic in so many scientific fields, we have dedicated this special issue of Journal of Physics: Condensed Matter to the topic of protein aggregation and disease. In the following pages we have collected two reviews and five articles that explore new and interesting developments in the field. References [1] Olby R 1994 The Path of the Double Helix: The Discovery of DNA (New York: Dover) [2] Dobson C M 2004 Principles of protein folding, misfolding and aggregation Semin. Cell Dev. Biol. 15 3-16 [3] Hammer N D, Wang X, McGuffie B A, Chapman M R 2008 Amyloids: friend or foe? J. Alzheimers Dis. 13 407-19 Physics and biology of neurodegenerative diseases contents Protein aggregation and misfolding: good or evil?Annalisa Pastore and Pierandrea Temussi Alzheimer's disease: biological aspects, therapeutic perspectives and diagnostic toolsM Di Carlo, D Giacomazza and P L San Biagio Entrapment of Aβ1-40 peptide in unstructured aggregatesC Corsale, R Carrotta, M R Mangione, S Vilasi, A Provenzano, G Cavallaro, D Bulone and P L San Biagio Elemental micro

  16. Inverse operator theory method and its applications in nonlinear physics

    International Nuclear Information System (INIS)

    Inverse operator theory method, which has been developed by G. Adomian in recent years, and its applications in nonlinear physics are described systematically. The method can be an unified effective procedure for solution of nonlinear and/or stochastic continuous dynamical systems without usual restrictive assumption. It is realized by Mathematical Mechanization by us. It will have a profound on the modelling of problems of physics, mathematics, engineering, economics, biology, and so on. Some typical examples of the application are given and reviewed

  17. Working together at the interface of physics and biology

    International Nuclear Information System (INIS)

    Good communication, whether it is between quorum-sensing bacteria or the different scientists studying those critters, is the key to a successful interdisciplinary collaboration, Bonnie Bassler and Ned Wingreen provide a personal perspective on working at the interface between the physical and biological sciences. (perspective)

  18. Subject Didactic Studies of Research Training in Biology and Physics.

    Science.gov (United States)

    Lybeck, Leif

    1984-01-01

    The objectives and design of a 3-year study of research training and supervision in biology and physics are discussed. Scientific problems arising from work on the thesis will be a focus for the postgraduate students and their supervisors. Attention will be focused on supervisors' and students' conceptions of science, subject range, research,…

  19. Perspectives on theory at the interface of physics and biology

    CERN Document Server

    Bialek, William

    2015-01-01

    Theoretical physics is the search for simple and universal mathematical descriptions of the natural world. In contrast, much of modern biology is an exploration of the complexity and diversity of life. For many, this contrast is prima facie evidence that theory, in the sense that physicists use the word, is impossible in a biological context. For others, this contrast serves to highlight a grand challenge. I'm an optimist, and believe (along with many colleagues) that the time is ripe for the emergence of a more unified theoretical physics of biological systems, building on successes in thinking about particular phenomena. In this essay I try to explain the reasons for my optimism, through a combination of historical and modern examples.

  20. Biological Physics major as a means to stimulate an undergraduate physics program

    Science.gov (United States)

    Jaeger, Herbert; Eid, Khalid; Yarrison-Rice, Jan

    2013-03-01

    In an effort to stress the cross-disciplinary nature of modern physics we added a Biological Physics major. Drawing from coursework in physics, biology, chemistry, mathematics, and related disciplines, it combines a broad curriculum with physical and mathematical rigor in preparation for careers in biophysics, medical physics, and biomedical engineering. Biological Physics offers a new path of studies to a large pool of life science students. We hope to grow our physics majors from 70-80 to more than 100 students and boost our graduation rate from the mid-teens to the mid-twenties. The new major brought about a revision of our sophomore curriculum to make room for modern topics without sidelining fundamentals. As a result, we split our 1-semester long Contemporary Physics course (4 cr hrs) into a year-long sequence Contemporary Physics Foundations and Contemporary Physics Frontiers (both 3 cr hrs). Foundations starts with relativity, then focuses on 4 quantum mechanics topics: wells, spin 1/2, oscillators, and hydrogen. Throughout the course applications are woven in whenever the opportunity arises, e.g. magnetism and NMR with spin 1/2. The following semester Frontiers explores scientific principles and technological advances that make quantum science and resulting technologies different from the large scale. Frontiers covers enabling techniques from atomic, molecular, condensed matter, and particle physics, as well as advances in nanotechnology, quantum optics, and biophysics.

  1. SCALING METHODS IN SOIL PHYSICS

    Science.gov (United States)

    Soil physical properties are needed to understand and manage natural systems spanning an extremely wide range of scales. Much of soil data are obtained from small soil samples and cores, monoliths, or small field plots, yet the goal is to reconstruct soil physical properties across fields, watershed...

  2. DNA confinement in nanochannels: physics and biological applications

    DEFF Research Database (Denmark)

    Reisner, Walter; Pedersen, Jonas Nyvold; Austin, Robert H

    2012-01-01

    biological interest in extracting linear sequence information from elongated DNA molecules, from a physics view these systems are fascinating as they enable probing of single-molecule conformation in environments with dimensions that intersect key physical length-scales in the 1 nm to 100μm range. (Some......DNA is the central storage molecule of genetic information in the cell, and reading that information is a central problem in biology. While sequencing technology has made enormous advances over the past decade, there is growing interest in platforms that can readout genetic information directly...... nanochannels, creating a linear unscrolling of the genome along the channel for analysis. We will first review the fundamental physics of DNA nanochannel confinement—including the effect of varying ionic strength—and then discuss recent applications of these systems to genomic mapping. Apart from the intense...

  3. Shoreline clean-up methods : biological treatments

    Energy Technology Data Exchange (ETDEWEB)

    Massoura, S.T. [Oil Spill Response Limited, Southampton (United Kingdom)

    2009-07-01

    The cleanup of oil spills in shoreline environments is a challenging issue worldwide. Oil spills receive public and media attention, particularly in the event of a coastal impact. It is important to evaluate the efficiency and effectiveness of cleanup methods when defining the level of effort and consequences that are appropriate to remove or treat different types of oil on different shoreline substrates. Of the many studies that have compared different mechanical, chemical and biological treatments for their effectiveness on various types of oil, biological techniques have received the most attention. For that reason, this paper evaluated the effectiveness and effects of shoreline cleanup methods using biological techniques. It summarized data from field experiments and oil spill incidents, including the Exxon Valdez, Sea Empress, Prestige, Grand Eagle, Nakhodka, Guanabara Bay and various Gulf war oil spills. Five major shoreline types were examined, notably rocky intertidal, cobble/pebble/gravel, sand/mud, saltmarsh, and mangrove/sea-grass. The biological techniques that were addressed were nutrient enrichment, hydrocarbon-utilizing bacteria, vegetable oil biosolvents, plants, surf washing, oil-particle interactions and natural attenuation. The study considered the oil type, volume and fate of stranded oil, location of coastal materials, extent of pollution and the impact of biological techniques. The main factors that affect biodegradation of hydrocarbons are the volume, chemical composition and weathering state of the petroleum product as well as the temperature, oxygen availability of nutrients, water salinity, pH level, water content, and microorganisms in the shoreline environment. The interaction of these factors also affect the biodegradation of oil. It was concluded that understanding the fate of stranded oil can help in the development of techniques that improve the weathering and degradation of oil on complex shoreline substrates. 39 refs.

  4. Breaking Frontiers: Submicron Structures in Physics and Biology - 52 Zakopane School of Physics

    International Nuclear Information System (INIS)

    The 52 Zakopane School of Physics held in Zakopane from 19 to 24 May 2008. The main task of the symposium was to present the newest results of research in field of submicron structures in physics, biology and medicine. Some new technologies as well as their applications are also presented

  5. Methods for solving mathematical physics problems

    CERN Document Server

    Agoshkov, VI; Shutyaev, VP

    2006-01-01

    The book examines the classic and generally accepted methods for solving mathematical physics problems (method of the potential theory, the eigenfunction method, integral transformation methods, discretisation characterisation methods, splitting methods). A separate chapter is devoted to methods for solving nonlinear equations. The book offers a large number of examples of how these methods are applied to the solution of specific mathematical physics problems, applied in the areas of science and social activities, such as energy, environmental protection, hydrodynamics, theory of elasticity, etc.

  6. Effects of weak magnetic fields on biological systems: physical aspects

    International Nuclear Information System (INIS)

    The effect of weak magnetic fields on biosystems is the subject matter of the science of magnetobiology. There are objective factors, due to theory lagging far behind experiment, that are hindering the development of this science. Academic interest in the subject is restrained by the fact that experimental data lack a clear physical explanation. Besides, there is a strong imbalance in how physics and biology are involved in magnetobiology, the former being still in infancy in this respect. It is this imbalance which is currently the driving force for the development of the theory of magnetobiology. This brief analytical review focuses on the physical aspects of magnetobiological research. The task of magnetobiology is to explore the biological effects of weak magnetic fields and to understand mechanisms behind these effects. Magnetobiology is part of a more general issue of the biological impact of weak and hyperweak physico-chemical factors. It is believed that such factors operate even below the trigger threshold for protective biological mechanisms and are therefore capable of accumulating at the subcellular level. The so-called 'kT-problem' is discussed in detail, and the interference mechanisms of the molecular gyroscope and of molecular states in an idealized protein cavity are suggested as candidate solutions. (reviews of topical problems)

  7. Charge Migration in DNA Perspectives from Physics, Chemistry, and Biology

    CERN Document Server

    Chakraborty, Tapash

    2007-01-01

    Charge migration through DNA has been the focus of considerable interest in recent years. A deeper understanding of the nature of charge transfer and transport along the double helix is important in fields as diverse as physics, chemistry and nanotechnology. It has also important implications in biology, in particular in DNA damage and repair. This book presents contributions from an international team of researchers active in this field. It contains a wide range of topics that includes the mathematical background of the quantum processes involved, the role of charge transfer in DNA radiation damage, a new approach to DNA sequencing, DNA photonics, and many others. This book should be of value to researchers in condensed matter physics, chemical physics, physical chemistry, and nanoscale sciences.

  8. Statistical methods in radiation physics

    CERN Document Server

    Turner, James E; Bogard, James S

    2012-01-01

    This statistics textbook, with particular emphasis on radiation protection and dosimetry, deals with statistical solutions to problems inherent in health physics measurements and decision making. The authors begin with a description of our current understanding of the statistical nature of physical processes at the atomic level, including radioactive decay and interactions of radiation with matter. Examples are taken from problems encountered in health physics, and the material is presented such that health physicists and most other nuclear professionals will more readily understand the application of statistical principles in the familiar context of the examples. Problems are presented at the end of each chapter, with solutions to selected problems provided online. In addition, numerous worked examples are included throughout the text.

  9. Statistical methods in physical mapping

    International Nuclear Information System (INIS)

    One of the great success stories of modern molecular genetics has been the ability of biologists to isolate and characterize the genes responsible for serious inherited diseases like fragile X syndrome, cystic fibrosis and myotonic muscular dystrophy. This dissertation concentrates on constructing high-resolution physical maps. It demonstrates how probabilistic modeling and statistical analysis can aid molecular geneticists in the tasks of planning, execution, and evaluation of physical maps of chromosomes and large chromosomal regions. The dissertation is divided into six chapters. Chapter 1 provides an introduction to the field of physical mapping, describing the role of physical mapping in gene isolation and ill past efforts at mapping chromosomal regions. The next two chapters review and extend known results on predicting progress in large mapping projects. Such predictions help project planners decide between various approaches and tactics for mapping large regions of the human genome. Chapter 2 shows how probability models have been used in the past to predict progress in mapping projects. Chapter 3 presents new results, based on stationary point process theory, for progress measures for mapping projects based on directed mapping strategies. Chapter 4 describes in detail the construction of all initial high-resolution physical map for human chromosome 19. This chapter introduces the probability and statistical models involved in map construction in the context of a large, ongoing physical mapping project. Chapter 5 concentrates on one such model, the trinomial model. This chapter contains new results on the large-sample behavior of this model, including distributional results, asymptotic moments, and detection error rates. In addition, it contains an optimality result concerning experimental procedures based on the trinomial model. The last chapter explores unsolved problems and describes future work

  10. Statistical methods in physical mapping

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, D.O. [Univ. of California, Berkeley, CA (United States)

    1995-05-01

    One of the great success stories of modern molecular genetics has been the ability of biologists to isolate and characterize the genes responsible for serious inherited diseases like fragile X syndrome, cystic fibrosis and myotonic muscular dystrophy. This dissertation concentrates on constructing high-resolution physical maps. It demonstrates how probabilistic modeling and statistical analysis can aid molecular geneticists in the tasks of planning, execution, and evaluation of physical maps of chromosomes and large chromosomal regions. The dissertation is divided into six chapters. Chapter 1 provides an introduction to the field of physical mapping, describing the role of physical mapping in gene isolation and ill past efforts at mapping chromosomal regions. The next two chapters review and extend known results on predicting progress in large mapping projects. Such predictions help project planners decide between various approaches and tactics for mapping large regions of the human genome. Chapter 2 shows how probability models have been used in the past to predict progress in mapping projects. Chapter 3 presents new results, based on stationary point process theory, for progress measures for mapping projects based on directed mapping strategies. Chapter 4 describes in detail the construction of all initial high-resolution physical map for human chromosome 19. This chapter introduces the probability and statistical models involved in map construction in the context of a large, ongoing physical mapping project. Chapter 5 concentrates on one such model, the trinomial model. This chapter contains new results on the large-sample behavior of this model, including distributional results, asymptotic moments, and detection error rates. In addition, it contains an optimality result concerning experimental procedures based on the trinomial model. The last chapter explores unsolved problems and describes future work.

  11. Some mathematical methods of physics

    CERN Document Server

    Goertzel, Gerald

    2014-01-01

    This well-rounded, thorough treatment for advanced undergraduates and graduate students introduces basic concepts of mathematical physics involved in the study of linear systems. The text emphasizes eigenvalues, eigenfunctions, and Green's functions. Prerequisites include differential equations and a first course in theoretical physics.The three-part presentation begins with an exploration of systems with a finite number of degrees of freedom (described by matrices). In part two, the concepts developed for discrete systems in previous chapters are extended to continuous systems. New concepts u

  12. DEGRO 2009. Radiation oncology - medical physics - radiation biology. Abstracts

    International Nuclear Information System (INIS)

    The special volume of the journal covers the abstracts of the DEGRO 2009 meeting on radiation oncology, medical physics, and radiation biology, covering the following topics: seldom diseases, gastrointestinal tumors, radiation reactions and radiation protection, medical care and science, central nervous system, medical physics, the non-parvicellular lung carcinomas, ear-nose-and throat, target-oriented radiotherapy plus ''X'', radio-oncology - young academics, lymphomas, mammary glands, modern radiotherapy, life quality and palliative radiotherapy, radiotherapy of the prostate carcinoma, imaging for planning and therapy, the digital documentation in clinics and practical experiences, NMR imaging and tomography, hadrons - actual status in Germany, urinal tract oncology, radiotoxicity

  13. 2010 Diffraction Methods in Structural Biology

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Ana Gonzalez

    2011-03-10

    Advances in basic methodologies have played a major role in the dramatic progress in macromolecular crystallography over the past decade, both in terms of overall productivity and in the increasing complexity of the systems being successfully tackled. The 2010 Gordon Research Conference on Diffraction Methods in Structural Biology will, as in the past, focus on the most recent developments in methodology, covering all aspects of the process from crystallization to model building and refinement, complemented by examples of structural highlights and complementary methods. Extensive discussion will be encouraged and it is hoped that all attendees will participate by giving oral or poster presentations, the latter using the excellent poster display area available at Bates College. The relatively small size and informal atmosphere of the meeting provides an excellent opportunity for all participants, especially younger scientists, to meet and exchange ideas with leading methods developers.

  14. Atmospheric physics. Background - methods - trends

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, Ulrich (ed.) [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    2012-11-01

    Presents more than 51 outstanding contributions of DLR-IPA to Atmospheric science. Gives a specific reference to Aerospace aspects. Prepared for educated laymen readers. Self-explaining. Understandable without the need to read references. On the occasion of the 50th anniversary of the Institute of Atmospheric Physics of the German Aerospace Center (DLR), this book presents more than 50 chapters highlighting results of the institute's research. The book provides an up-to-date, in-depth survey across the entire field of atmospheric science, including atmospheric dynamics, radiation, cloud physics, chemistry, climate, numerical simulation, remote sensing, instruments and measurements, as well as atmospheric acoustics. The authors have provided a readily comprehensible and self-contained presentation of the complex field of atmospheric science. The topics are of direct relevance for aerospace science and technology. Future research challenges are identified.

  15. Integrated Graduate Program in Physical and Engineering Biology at Yale University

    Science.gov (United States)

    Caballero, Diego; Noble, Dorottya; Pollard, Thomas; Mochrie, Simon; O'Hern, Corey; Regan, Lynne

    2014-03-01

    Quantitative, integrated approaches are necessary to solve biology's grand challenges. Yale's Integrated Graduate Program in Physical and Engineering Biology (IGPPEB) prepares students to excel at applying physics and engineering approaches, whilst also ensuring that they are sufficiently biologically sophisticated that they can readily identify and tackle cutting-edge problems. Students enter the program through a ``home'' department but also take a set of IGPPEB core courses with students from other departments. The IGPPEB curriculum is co-taught by faculty from a wide array of departments and motivates students to work together and learn from each other. The curriculum complements those of the home departments and includes primer courses to rapidly bring all students to a level where they ``speak each others language.'' The program is a member of the NSF's Physics of Living Systems: Student Research Network, which connects graduate students from different institutions that are engaged in research at the interface of physics and biology. Convergent research thrusts at Yale include Cellular Shape and Motion; Mechanical Force Generation and Sensing; Biomaterials and Bioinspired Design; Systems and Synthetic Biology; Modeling Biological Processes and Methods Development.

  16. Optimizing Introductory Physics for the Life Sciences: Placing Physics in Biological Context

    Science.gov (United States)

    Crouch, Catherine

    2014-03-01

    Physics is a critical foundation for today's life sciences and medicine. However, the physics content and ways of thinking identified by life scientists as most important for their fields are often not taught, or underemphasized, in traditional introductory physics courses. Furthermore, such courses rarely give students practice using physics to understand living systems in a substantial way. Consequently, students are unlikely to recognize the value of physics to their chosen fields, or to develop facility in applying physics to biological systems. At Swarthmore, as at several other institutions engaged in reforming this course, we have reorganized the introductory course for life science students around touchstone biological examples, in which fundamental physics contributes significantly to understanding biological phenomena or research techniques, in order to make explicit the value of physics to the life sciences. We have also focused on the physics topics and approaches most relevant to biology while seeking to develop rigorous qualitative reasoning and quantitative problem solving skills, using established pedagogical best practices. Each unit is motivated by and culminates with students analyzing one or more touchstone examples. For example, in the second semester we emphasize electric potential and potential difference more than electric field, and start from students' typically superficial understanding of the cell membrane potential and of electrical interactions in biochemistry to help them develop a more sophisticated understanding of electric forces, field, and potential, including in the salt water environment of life. Other second semester touchstones include optics of vision and microscopes, circuit models for neural signaling, and magnetotactic bacteria. When possible, we have adapted existing research-based curricular materials to support these examples. This talk will describe the design and development process for this course, give examples of

  17. Preservice Teachers' Epistemological Beliefs in Physics, Chemistry, and Biology: A Mixed Study

    Science.gov (United States)

    Topcu, Mustafa Sami

    2013-01-01

    The purposes of the study were to assess preservice teachers' domain-specific epistemological beliefs and to investigate whether preservice teachers distinguish disciplinary differences (physics, chemistry, and biology) in domain-specific epistemological beliefs. Mixed-method research design guided the present research. The researcher explored…

  18. Physical parameters and biological effects of the LVR-15 epithermal neutron beam

    International Nuclear Information System (INIS)

    Monitoring of the physical and biological properties of the epithermal neutron beam constructed at the multipurpose LVR-15 nuclear reactor for NCT therapy of brain tumors showed that its physical and biological properties are stable in time and independent on an ad hoc reconfiguration of the reactor core before its therapeutic use. Physical parameters were monitored by measurement of the neutron spectrum, neutron profile, fast neutron kerma rate in tissue and photon absorbed dose, the gel dosimetry was used with the group of standard measurement methods. The RBE of the beam, as evaluated by 3 different biological models, including mouse intestine crypt regeneration assay, germinative zones of the immature rat brain and C6 glioma cells in culture, ranged from 1.70 to 1.99. (author)

  19. The Effects Of Physical And Biological Cohesion On Bedforms

    Science.gov (United States)

    Parsons, D. R.; Schindler, R.; Baas, J.; Hope, J. A.; Malarkey, J.; Paterson, D. M.; Peakall, J.; Manning, A. J.; Ye, L.; Aspden, R.; Alan, D.; Bass, S. J.

    2014-12-01

    Most coastal sediments consist of complex mixtures of cohesionless sands, physically-cohesive clays and extra cellular polymeric substances (EPS) that impart biological cohesion. Yet, our ability to predict bedform dimensions in these substrates is reliant on predictions based exclusively on cohesionless sand. We present findings from the COHBED project - which explicitly examines how bedform dynamics are modified by natural cohesion. Our experimental results show that for ripples, height and length are inversely proportional to initial clay content and bedforms take longer to appear, with no ripples when clay content exceeds 18%. When clay is replaced by EPS the development time and time of first appearance of ripples both increase by two orders of magnitude, with no bedforms above 0.125% EPS. For dunes, height and length are also inversely proportional to initial substrate clay content, resulting in a transition from dunes to ripples normally associated with velocity decreases. Addition of low EPS concentrations into the substrate results in yet smaller bedforms at the same clay contents and at high EPS concentrations, biological cohesion supersedes all electrostatic bonding, and bedform size is no longer related to mud content. The contrast in physical and biological cohesion effects on bedform development result from the disparity between inter-particle electrostatic bonding of clay particles and EPS grain coating and strands that physically link sediments together, which effects winnowing rates as bedforms evolve. These findings have wide ranging implications for bedform predictions in both modern and ancient environments. Coupling of biological and morphological processes not only requires an understanding of how bedform dimensions influence biota and habitat, but also how benthic species can modify bedform dimensions. Consideration of both aspects provides a means in which fluid dynamics, sediment transport and ecosystem energetics can be linked to yield

  20. Molecular physics. Theoretical principles and experimental methods

    International Nuclear Information System (INIS)

    This advanced textbook comprehensively explains important principles of diatomic and polyatomic molecules and their spectra in two separate, distinct parts. The first part concentrates on the theoretical aspects of molecular physics, whereas the second part of the book covers experimental techniques, i.e. laser, Fourier, NMR, and ESR spectroscopies, used in the fields of physics, chemistry, biolog, and material science. Appropriate for undergraduate and graduate students in physics and chemistry with a knowledge of atomic physics and familiar with the basics of quantum mechanics. From the contents: - Electronic States of Molecules, - Rotation, Oscillation and Potential Curves of Diatomic Molecules, - The Spectra of Diatomic Molecules, - Molecule Symmetries and Group Theory, - Rotation and Oscillations of Polyatomic Molecules, - Electronic States of Polyatomic Molecules, - The Spectra of Polyatomic Molecules, - Collapse of the Born-Oppenheimer-Approximation, Disturbances in Molecular Spectra, - Molecules in Disturbing Fields, - Van-der-Waals-Molecules and Cluster, - Experimental Techniques in Molecular Physics. (orig.)

  1. Competency-based reforms of the undergraduate biology curriculum: integrating the physical and biological sciences.

    Science.gov (United States)

    Thompson, Katerina V; Chmielewski, Jean; Gaines, Michael S; Hrycyna, Christine A; LaCourse, William R

    2013-06-01

    The National Experiment in Undergraduate Science Education project funded by the Howard Hughes Medical Institute is a direct response to the Scientific Foundations for Future Physicians report, which urged a shift in premedical student preparation from a narrow list of specific course work to a more flexible curriculum that helps students develop broad scientific competencies. A consortium of four universities is working to create, pilot, and assess modular, competency-based curricular units that require students to use higher-order cognitive skills and reason across traditional disciplinary boundaries. Purdue University; the University of Maryland, Baltimore County; and the University of Miami are each developing modules and case studies that integrate the biological, chemical, physical, and mathematical sciences. The University of Maryland, College Park, is leading the effort to create an introductory physics for life sciences course that is reformed in both content and pedagogy. This course has prerequisites of biology, chemistry, and calculus, allowing students to apply strategies from the physical sciences to solving authentic biological problems. A comprehensive assessment plan is examining students' conceptual knowledge of physics, their attitudes toward interdisciplinary approaches, and the development of specific scientific competencies. Teaching modules developed during this initial phase will be tested on multiple partner campuses in preparation for eventual broad dissemination. PMID:23737624

  2. Suitability of Gray Water for Hydroponic Crop Production Following Biological and Physical Chemical and Biological Subsystems

    Science.gov (United States)

    Bubenheim, David L.; Harper, Lynn D.; Wignarajah, Kanapathipillai; Greene, Catherine

    1994-01-01

    The water present in waste streams from a human habitat must be recycled in Controlled Ecological Life Support Systems (CELSS) to limit resupply needs and attain self-sufficiency. Plants play an important role in providing food, regenerating air, and producing purified water via transpiration. However, we have shown that the surfactants present in hygiene waste water have acute toxic effects on plant growth (Bubenheim et al. 1994; Greene et al., 1994). These phytotoxic affects can be mitigated by allowing the microbial population on the root surface to degrade the surfactant, however, a significant suppression (several days) in crop performance is experienced prior to reaching sub-toxic surfactant levels and plant recovery. An effective alternative is to stabilize the microbial population responsible for degradation of the surfactant on an aerobic bioreactor and process the waste water prior to utilization in the hydroponic solution (Wisniewski and Bubenheim, 1993). A sensitive bioassay indicates that the surfactant phytotoxicity is suppressed by more than 90% within 5 hours of introduction of the gray water to the bioreactor; processing for more than 12 hours degrades more than 99% of the phytotoxin. Vapor Compression Distillation (VCD) is a physical / chemical method for water purification which employees sequential distillation steps to separate water from solids and to volatilize contaminants. The solids from the waste water are concentrated in a brine and the pure product water (70 - 90% of the total waste water volume depending on operating conditions) retains non of the phytotoxic effects. Results of the bioassay were used to guide evaluations of the suitability of recovered gray water following biological and VCD processing for hydroponic lettuce production in controlled environments. Lettuce crops were grown for 28 days with 100% of the input water supplied with recovered water from the biological processor or VCD. When compared with the growth of plants

  3. The Gravity of Regenerative Medicine; Physics, Chemistry & Biology behind it

    Directory of Open Access Journals (Sweden)

    Dedeepiya V

    2008-01-01

    Full Text Available The in-vitro expansion of cells of the organs/tissues and their re-implantation into the affected region/ tissue for treating cell/organ failure have been in practice for long, but in limited specialties. The in-vitro cell culture protocols use variety of biological reagents derived from animal sources and recombinant technologies. However, the optimal quantity of such biological components such as growth factors, cytokines etc.,needed for such cells to be grown in a non-physiological environment is still unknown. The use of such biological components have started to stir a controversy of late, due to the recognition of its potential hazards such as spread of prion diseases and contamination with non-human sialic acid proteins. Therefore synthetic reproducible biomaterials are gaining popularity in cell culture and tissue engineering. The biomaterials made of several chemical components based on physical parameters are starting to change certain concepts about the niche of cell culture and that of stem cell expansion and differentiation to specific lineages. Engler et al have already proven that a simple change in the matrix elasticity alone could change the lineage of the cells. Spencer et al have reported that a change in bioelectricity could change the morphogenesis during development. NCRM has been involved in cell culture and tissue engineering using approximately 240 different materials ranging from polymer hydrogel, gel with adherent inserts, nano composite materials, nano-coating technologies, nano-sheets and nano-films. These materials are used in cell culture in different hybrid combinations such as Floating 3D cell culture without adherent components in a homogenous hydrogel. Floating 3D cell culture with anchorage inserts. Flat surface- 2D adherent cell culture. Combined flat surface 2D cell culture (for differentiating cells and floating 3D culture (for undifferentiated cells. These combinations have started yielding several

  4. The Influence of Physical & Biological Cohesion on Dune Development

    Science.gov (United States)

    Schindler, Robert; Parsons, Daniel; Ye, Leiping; Baas, Jaco; Hope, Julie; Manning, Andy; Malarkey, Jonathan; Aspden, Rebecca; Lichtman, Dougal; Thorne, Peter; Peakall, Jeff; Patterson, David; Davies, Alan; Bass, Sarah; O'Boyle, Louise

    2014-05-01

    Existing predictions for dune bedforms are based on simplified physical parameters, with assumptions that sediment consists only of cohesionless sand. They do not include the complexities of mud: physical cohesion is imparted by cohesive clays and biological cohesion is created by the presence of organisms which, among other things, generate extra-cellular polymers (EPS). Using controlled experiments we show the profound influence on the size, development and equilibrium morphology of dune bedforms of both physical and biological cohesion. Experiments were completed at the Total Environment Simulator facility at Hull University, UK in a 10 x 2 m channel. A flat sediment bed was laid to 0.15 m depth. A unidirectional flow of 0.25 m depth was passed over the sediment for 10 h. In Phase 1 eight different sand:clay mixes were examined, where clay content was 18.0 - 2.1%. In Phase 2, the same mixtures were used with additions of EPS. A velocity of 0.8 m s-1 was used throughout, corresponding to the dune regime for the selected sand. Bedform development was monitored via ultrasonic ranging transducers, sediment cores and water samples. Phase 1 showed substantial differences in bedform type with clay content, with size inversely related to clay content, e.g. Run 1 (18.0% clay) generated 2D ripples; Run 7 (2.1% clay) generated 3D dunes. Transitional forms, included dunes with superimposed ripples, were present between these extremes. In Phase 2, EPS contents equivalent to only 1/30th of 1% by mass prevented the development of bedforms. Bedforms were generated in sediments with 1/20th and 1/10th of 1%, with an inverse relationship between bedform size and EPS content. Comparison of Phase 1 and Phase 2 runs with equal sand:mud ratios reveals that EPS acts to severely inhibit bedform development compared with the mud-only case. We can conclude that (1) the ripple-dune transition can occur under constant flow conditions, i.e. clay content may dictate bedform type, that (2) EPS

  5. Biological and Physical Space Research Laboratory 2002 Science Review

    Science.gov (United States)

    Curreri, P. A. (Editor); Robinson, M. B. (Editor); Murphy, K. L. (Editor)

    2003-01-01

    With the International Space Station Program approaching core complete, our NASA Headquarters sponsor, the new Code U Enterprise, Biological and Physical Research, is shifting its research emphasis from purely fundamental microgravity and biological sciences to strategic research aimed at enabling human missions beyond Earth orbit. Although we anticipate supporting microgravity research on the ISS for some time to come, our laboratory has been vigorously engaged in developing these new strategic research areas.This Technical Memorandum documents the internal science research at our laboratory as presented in a review to Dr. Ann Whitaker, MSFC Science Director, in July 2002. These presentations have been revised and updated as appropriate for this report. It provides a snapshot of the internal science capability of our laboratory as an aid to other NASA organizations and the external scientific community.

  6. ACTIVE AND PARTICIPATORY METHODS IN BIOLOGY: MODELING

    Directory of Open Access Journals (Sweden)

    Brînduşa-Antonela SBÎRCEA

    2011-01-01

    Full Text Available By using active and participatory methods it is hoped that pupils will not only come to a deeper understanding of the issues involved, but also that their motivation will be heightened. Pupil involvement in their learning is essential. Moreover, by using a variety of teaching techniques, we can help students make sense of the world in different ways, increasing the likelihood that they will develop a conceptual understanding. The teacher must be a good facilitator, monitoring and supporting group dynamics. Modeling is an instructional strategy in which the teacher demonstrates a new concept or approach to learning and pupils learn by observing. In the teaching of biology the didactic materials are fundamental tools in the teaching-learning process. Reading about scientific concepts or having a teacher explain them is not enough. Research has shown that modeling can be used across disciplines and in all grade and ability level classrooms. Using this type of instruction, teachers encourage learning.

  7. From high dilutions to digital biology: the physical nature of the biological signal.

    Science.gov (United States)

    Thomas, Yolène

    2015-10-01

    The memory of water was a radical idea that arose in the laboratory of Jacques Benveniste in the late 1980s. Twenty-five years have passed and yet the often angry debate on its merits continues despite the increasing number of scientists who have reported confirmation of the basic results. One working hypothesis was that molecules can communicate with each other, exchanging information without being in physical contact and that at least some biological functions can be mimicked by certain energetic modes characteristics of a given molecule. These considerations informed exploratory research which led to the speculation that biological signaling might be transmissible by electromagnetic means. Around 1991, the transfer of specific molecular signals to sensitive biological systems was achieved using an amplifier and electromagnetic coils. In 1995, a more sophisticated procedure was established to record, digitize and replay these signals using a multimedia computer. From a physical and chemical perspective, these experiments pose a riddle, since it is not clear what mechanism can sustain such 'water memory' of the exposure to molecular signals. From a biological perspective, the puzzle is what nature of imprinted effect (water structure) can impact biological function. A parallel can be drawn between this debate on the memory of water, which presumes that the action of molecules is mediated by an electromagnetic phenomenon, and the often acrimonious debate on the transmission of nerve influxes via synaptic transfer of specific molecules, neurotransmitters. The latter debate began in 1921 with the first experiments by Loewi and was still active in 1949, 28 years later. A strong reluctance to accept research that questions basic aspects of long-accepted biochemical paradigms is to be expected. In this paper we will provide a brief summary of experiments relating to the memory of water: the earlier work on high dilutions (HD) and then the experiments, which followed and

  8. Dynamic light scattering with applications to chemistry, biology, and physics

    CERN Document Server

    Berne, Bruce J

    2000-01-01

    Lasers play an increasingly important role in a variety of detection techniques, making inelastic light scattering a tool of growing value in the investigation of dynamic and structural problems in chemistry, biology, and physics. Until the initial publication of this work, however, no monograph treated the principles behind current developments in the field.This volume presents a comprehensive introduction to the principles underlying laser light scattering, focusing on the time dependence of fluctuations in fluid systems; it also serves as an introduction to the theory of time correlation f

  9. Network biology methods integrating biological data for translational science

    OpenAIRE

    Bebek, Gurkan; Koyutürk, Mehmet; Nathan D Price; Mark R Chance

    2012-01-01

    The explosion of biomedical data, both on the genomic and proteomic side as well as clinical data, will require complex integration and analysis to provide new molecular variables to better understand the molecular basis of phenotype. Currently, much data exist in silos and is not analyzed in frameworks where all data are brought to bear in the development of biomarkers and novel functional targets. This is beginning to change. Network biology approaches, which emphasize the interactions betw...

  10. Use of radiotracers in Romanian physical and biological oceanography

    International Nuclear Information System (INIS)

    The use and importance of isotope techniques are already well known in various scientific and technological fields, among the sciences of top interest the oceanography being included. Romanian research and experience in this respect mostly refer to physical and biological oceanography studies in the Black Sea, a real 'unicum hydrobiologicum' (Knipovich, 1932) with a particular emphasis on the western coast. Several applications of radiotracers were promoted by the Romanian Marine Research Institute (Constanta, Romania) in close co-operation with the Institute of Physics and Nuclear Engineering (Bucharest-Magurele, Romania), since 1970; these are listed in the following studies: a) determination of the sediment transport in the nearshore area (Ta-182, Zr-95, Sc-46); b) determination of turbulent diffusion coefficients (Br-82); c) estimate of planktonic primary productivity (C-14). (author)

  11. Health: The No-Man's-Land Between Physics and Biology.

    Science.gov (United States)

    Mansfield, Peter J

    2015-10-01

    Health as a positive attribute is poorly understood because understanding requires concepts from physics, of which physicians and other life scientists have a very poor grasp. This paper reviews the physics that bears on biology, in particular complex quaternions and scalar fields, relates these to the morphogenetic fields proposed by biologists, and defines health as an attribute of living action within these fields. The distinction of quality, as juxtaposed with quantity, proves essential. Its basic properties are set out, but a science and mathematics of quality are awaited. The implications of this model are discussed, particularly as proper health enhancement could set a natural limit to demand for, and therefore the cost of, medical services. PMID:26447724

  12. Improving Performance through Motivation: Teaching Biology Pre-Med Students Physics

    Science.gov (United States)

    Gregg, Elena

    2013-03-01

    Several major factors which affect students' learning are assessed (curricula, different teaching approaches, assessment methods, engagement, and motivation). Direct connection between motivation, attitudes, self-confidence and achievement was established. It was demonstrated that improvement of motivation and self-confidence among students (particularly females, minorities and low achievers) is essential. Effectiveness of different instructional methods and motivational approaches was analyzed and evaluated in algebra-based Physics course for Biology pre-med undergraduate students.

  13. Implementation of statistical analysis methods for medical physics data

    International Nuclear Information System (INIS)

    The objective of biomedical research with different radiation natures is to contribute for the understanding of the basic physics and biochemistry of the biological systems, the disease diagnostic and the development of the therapeutic techniques. The main benefits are: the cure of tumors through the therapy, the anticipated detection of diseases through the diagnostic, the using as prophylactic mean for blood transfusion, etc. Therefore, for the better understanding of the biological interactions occurring after exposure to radiation, it is necessary for the optimization of therapeutic procedures and strategies for reduction of radioinduced effects. The group pf applied physics of the Physics Institute of UERJ have been working in the characterization of biological samples (human tissues, teeth, saliva, soil, plants, sediments, air, water, organic matrixes, ceramics, fossil material, among others) using X-rays diffraction and X-ray fluorescence. The application of these techniques for measurement, analysis and interpretation of the biological tissues characteristics are experimenting considerable interest in the Medical and Environmental Physics. All quantitative data analysis must be initiated with descriptive statistic calculation (means and standard deviations) in order to obtain a previous notion on what the analysis will reveal. It is well known que o high values of standard deviation found in experimental measurements of biologicals samples can be attributed to biological factors, due to the specific characteristics of each individual (age, gender, environment, alimentary habits, etc). This work has the main objective the development of a program for the use of specific statistic methods for the optimization of experimental data an analysis. The specialized programs for this analysis are proprietary, another objective of this work is the implementation of a code which is free and can be shared by the other research groups. As the program developed since the

  14. Long-Range Correlations in Physical and Biological Systems.

    Science.gov (United States)

    Peng, Chung-Kang

    1993-01-01

    In this thesis, I explore a wide variety of physical and biological systems without any temporal (or spatial) characteristic scale. These systems are usually associated with the terms "fractal," "scale free," "1/f noise" and "long-range correlations." In the first part of the thesis, I discuss some general concepts of scale-free systems and introduce several useful analytic and numerical tools to describe and analyze them. In the second part, I study simple physical models that exhibit long-range correlations in their spatial or temporal sequences. Two concrete examples are the one -dimensional diffusion of hard-core particles and the diffusion of particles in a random velocity field. Although, both examples exhibit power-law behavior in their velocity auto -correlation function, higher order correlations are completely different. Furthermore, I apply a novel numerical algorithm for generating correlated stochastic variables to study numerically the behavior of a dynamical system in the presence of long-range correlated noise. In the last part, I present two biological systems with long-range correlations: The DNA sequences and the human heartbeat time series. Two observations are made: (1) By constructing a 1:1 map of the nucleotide sequence onto a walk--called a "DNA walk," one can show that long -range correlations exist in non-coding nucleotide sequences but not in cDNA (protein coding) sequences. (2) Under healthy conditions, cardiac interbeat interval dynamics exhibit long-term correlations; with severe pathology this correlation behavior breaks down. For both systems, I discuss possible origins of these correlations and their biological implications.

  15. Industrial applications of neutron physics methods

    International Nuclear Information System (INIS)

    Three areas where nuclear based techniques have significant are briefly described. These are: Nuclear material control and non-proliferation, on-line elemental analysis of coal and minerals, and non- detection of explosives and other contraband. The nuclear physics and the role of reactor physics methods are highlighted. (author). 5 refs., 10 figs., 5 tabs

  16. Photon activation method to the investigation of bioobjects content for juridical-biological examination

    International Nuclear Information System (INIS)

    Possibilities of the use of nuclear-physical methods for definition of element composition of biological objects (hair of animals) with the target of receipt of additional evidentiary information at the decision of diagnostics and identification problems within the limits of forensic-biological examination are shown

  17. Biological vs. physical mixing effects on benthic food web dynamics.

    Directory of Open Access Journals (Sweden)

    Ulrike Braeckman

    Full Text Available Biological particle mixing (bioturbation and solute transfer (bio-irrigation contribute extensively to ecosystem functioning in sediments where physical mixing is low. Macrobenthos transports oxygen and organic matter deeper into the sediment, thereby likely providing favourable niches to lower trophic levels (i.e., smaller benthic animals such as meiofauna and bacteria and thus stimulating mineralisation. Whether this biological transport facilitates fresh organic matter assimilation by the metazoan lower part of the food web through niche establishment (i.e., ecosystem engineering or rather deprives them from food sources, is so far unclear. We investigated the effects of the ecosystem engineers Lanice conchilega (bio-irrigator and Abra alba (bioturbator compared to abiotic physical mixing events on survival and food uptake of nematodes after a simulated phytoplankton bloom. The (13C labelled diatom Skeletonema costatum was added to 4 treatments: (1 microcosms containing the bioturbator, (2 microcosms containing the bio-irrigator, (3 control microcosms and (4 microcosms with abiotic manual surface mixing. Nematode survival and subsurface peaks in nematode density profiles were most pronounced in the bio-irrigator treatment. However, nematode specific uptake (Δδ(13C of the added diatoms was highest in the physical mixing treatment, where macrobenthos was absent and the diatom (13C was homogenised. Overall, nematodes fed preferentially on bulk sedimentary organic material rather than the added diatoms. The total C budget (µg C m(-2, which included TO(13C remaining in the sediment, respiration, nematode and macrobenthic uptake, highlighted the limited assimilation by the metazoan benthos and the major role of bacterial respiration. In summary, bioturbation and especially bio-irrigation facilitated the lower trophic levels mainly over the long-term through niche establishment. Since the freshly added diatoms represented only a limited food

  18. Biological vs. physical mixing effects on benthic food web dynamics.

    Science.gov (United States)

    Braeckman, Ulrike; Provoost, Pieter; Moens, Tom; Soetaert, Karline; Middelburg, Jack J; Vincx, Magda; Vanaverbeke, Jan

    2011-01-01

    Biological particle mixing (bioturbation) and solute transfer (bio-irrigation) contribute extensively to ecosystem functioning in sediments where physical mixing is low. Macrobenthos transports oxygen and organic matter deeper into the sediment, thereby likely providing favourable niches to lower trophic levels (i.e., smaller benthic animals such as meiofauna and bacteria) and thus stimulating mineralisation. Whether this biological transport facilitates fresh organic matter assimilation by the metazoan lower part of the food web through niche establishment (i.e., ecosystem engineering) or rather deprives them from food sources, is so far unclear. We investigated the effects of the ecosystem engineers Lanice conchilega (bio-irrigator) and Abra alba (bioturbator) compared to abiotic physical mixing events on survival and food uptake of nematodes after a simulated phytoplankton bloom. The (13)C labelled diatom Skeletonema costatum was added to 4 treatments: (1) microcosms containing the bioturbator, (2) microcosms containing the bio-irrigator, (3) control microcosms and (4) microcosms with abiotic manual surface mixing. Nematode survival and subsurface peaks in nematode density profiles were most pronounced in the bio-irrigator treatment. However, nematode specific uptake (Δδ(13)C) of the added diatoms was highest in the physical mixing treatment, where macrobenthos was absent and the diatom (13)C was homogenised. Overall, nematodes fed preferentially on bulk sedimentary organic material rather than the added diatoms. The total C budget (µg C m(-2)), which included TO(13)C remaining in the sediment, respiration, nematode and macrobenthic uptake, highlighted the limited assimilation by the metazoan benthos and the major role of bacterial respiration. In summary, bioturbation and especially bio-irrigation facilitated the lower trophic levels mainly over the long-term through niche establishment. Since the freshly added diatoms represented only a limited food source

  19. Advances in Physical and Biological Radiation Detectors. Proceedings of a Symposium on New Developments in Physical and Biological Radiation Detectors

    International Nuclear Information System (INIS)

    Radiation dosimetry is a fundamental part of all radiation protection work. The measurements are made with a variety of instruments, and health physicists, after professional interpretation of the data, can assess the levels of exposure which might be encountered in a given area or the individual doses received by workers, visitors and others at places where the possibility of radiation exposure exists. The types of radiation concerned here are photon radiations, ranging from soft X-rays to gamma rays, and particulate radiations such as β-rays, α-particles, protons, neutrons and fission fragments. The type of technique used depends not only on the type of radiation but also on such factors as whether the radiation is from a source internal or external to the body. Radiation dosimetry is not only used at nuclear facilities; it has diverse applications, for example in determining doses when radiation sources are employed for medical diagnostics and therapy, in safeguarding workers in any industry where isotopes are used, and in assessing the effect of both naturally occurring and man-made radiations on the general public and the environment. The advances of modern technology have increased the variety of sources; an example can be given from colour television, where the high potential necessary in certain colour cathode-ray tubes generates a non-negligible amount of X-rays. The Symposium on New Developments in Physical and Biological Radiation Detectors was one of a continuing series of meetings in which the International Atomic Energy Agency furthers the exchange of information on all aspects of personnel and area dosimetry. The Symposium was devoted in particular to a study of the dose meters themselves - their radiation-sensitive elements (both physical and biological),their instrumentation, and calibration and standardization. Several speakers suggested that the situation in the standardization and calibration of measuring equipment and sources was

  20. Ultrasonic methods in solid state physics

    CERN Document Server

    Truell, John; Elbaum, Charles

    1969-01-01

    Ultrasonic Methods in Solid State Physics is devoted to studies of energy loss and velocity of ultrasonic waves which have a bearing on present-day problems in solid-state physics. The discussion is particularly concerned with the type of investigation that can be carried out in the megacycle range of frequencies from a few megacycles to kilomegacycles; it deals almost entirely with short-duration pulse methods rather than with standing-wave methods. The book opens with a chapter on a classical treatment of wave propagation in solids. This is followed by separate chapters on methods and techni

  1. [Chemical, physical and biological risks in law enforcement].

    Science.gov (United States)

    Magrini, Andrea; Grana, Mario; Vicentini, Laura

    2014-01-01

    Chemical, physical and biological risks among public safety and security forces. Law enforcement personnel, involved in routine tasks and in emergency situations, are exposed to numerous and several occupational hazards (chemical, physical and biological) whith likely health and security consequences. These risks are particularly high when the organization and preparation are inadequate, there is a lacking or insufficient coordination, information, education and communication and safety and personal protective equipment are inadequate or insufficient. Despite the objective difficulties, caused by the actual special needs related to the service performed or the organizational peculiarities, the risk identification and assessment is essential for worker health and safety of personnel, as provided for by Legislative Decree no. 81/2008. Chemical risks include airborne pollutants due to vehicular traffic (carbon monoxide, ultrafine particles, benzene, polycyclic aromatic hydrocarbons, aldehydes, nitrogen and sulfur oxides, lead), toxic gases generated by combustion process following fires (aromatic hydrocarbons, PAHs, dioxins and furans, biphenyls, formaldehyde, metals and cyanides), substances emitted in case of chemical accidents (solvents, pesticides, toxic gases, caustics), drugs (methylamphetamine), riot control agents and self-defence spray, lead at firing ranges, and several materials and reagents used in forensic laboratory. The physical hazards are often caused by activities that induce biomechanical overload aid the onset of musculoskeletal disorders, the use of visual display terminals and work environments that may expose to heat stress and discomfort, high and low pressure, noise, vibrations, ionizing and non-ionizing radiation. The main biological risks are blood-borne diseases (viral hepatitis, AIDS), airborne diseases (eg, tuberculosis, meningitis, SARS, anthrax), MRSA, and vector-borne diseases. Many of these risk factors are unavoidable or are not

  2. Mathematical methods for physical and analytical chemistry

    CERN Document Server

    Goodson, David Z

    2011-01-01

    Mathematical Methods for Physical and Analytical Chemistry presents mathematical and statistical methods to students of chemistry at the intermediate, post-calculus level. The content includes a review of general calculus; a review of numerical techniques often omitted from calculus courses, such as cubic splines and Newton's method; a detailed treatment of statistical methods for experimental data analysis; complex numbers; extrapolation; linear algebra; and differential equations. With numerous example problems and helpful anecdotes, this text gives chemistry students the mathematical

  3. Biological methods of dye removal from textile effluents - A review

    Directory of Open Access Journals (Sweden)

    Archna *

    2012-08-01

    Full Text Available Textile dyes are molecules designed to impart permanent colours to textile fabrics. They pose an environmental problem due to their toxicity and decrease the aesthetic value of water bodies into which they are discharged. Current physico-chemical technologies for dye removal cannot remove all classes of dyes, and two or more technologies are usually combined to achieve satisfactory decolourisation efficiencies. Direct biological treatment using fungi or bacteria can also be employed, but nutritional and physiological requirements of microorganisms put constraints on the applicability of such bioremediation processes. The search for efficient and green oxidation technologies has increased the interest in the use of enzymes to replace the conventional non-biological methods. Among the different existing oxidant enzymes, laccase (benzenediol:oxygen oxidoreductases; EC 1.10.3.2 has been the subject of intensive research in the past few decades due to its low substrate specificity. Enzymatic treatment using laccase can be simpler and much more efficient than the traditional physical or chemical treatments. This paper reviews conventional biological processes as well as  laccase-based processes might replace the traditionally energy intensive and water-consuming chemical treatment operations in the textile industry. Keywords: Dyes, Decolourisation, Green Oxidation, Laccase, Textile industry  

  4. Physical analytical methods for uranium hexafluoride

    International Nuclear Information System (INIS)

    Various physical methods of analysis currently used or still under investigation such as: sound analysis, vapor pressure measurements, fractional distillation, cryogenics, micro-sublimation, ultra-violet, visible and infra-red absorption spectrophotometry, nuclear magnetic resonance and mass spectrometry are reviewed. For each method, principle and applications are given, and results obtained concerning reproducibility, application limits and rapidity are discussed. (author)

  5. Advanced analysis methods in particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Pushpalatha C.; /Fermilab

    2010-10-01

    Each generation of high energy physics experiments is grander in scale than the previous - more powerful, more complex and more demanding in terms of data handling and analysis. The spectacular performance of the Tevatron and the beginning of operations of the Large Hadron Collider, have placed us at the threshold of a new era in particle physics. The discovery of the Higgs boson or another agent of electroweak symmetry breaking and evidence of new physics may be just around the corner. The greatest challenge in these pursuits is to extract the extremely rare signals, if any, from huge backgrounds arising from known physics processes. The use of advanced analysis techniques is crucial in achieving this goal. In this review, I discuss the concepts of optimal analysis, some important advanced analysis methods and a few examples. The judicious use of these advanced methods should enable new discoveries and produce results with better precision, robustness and clarity.

  6. Evaluation of conformal radiotherapy techniques through physics and biologic criteria

    International Nuclear Information System (INIS)

    In the fight against cancer, different irradiation techniques have been developed based on technological advances and aiming to optimize the elimination of tumor cells with the lowest damage to healthy tissues. The radiotherapy planning goal is to establish irradiation technical parameters in order to achieve the prescribed dose distribution over the treatment volumes. While dose prescription is based on radiosensitivity of the irradiated tissues, the physical calculations on treatment planning take into account dosimetric parameters related to the radiation beam and the physical characteristics of the irradiated tissues. To incorporate tissue's radiosensitivity into radiotherapy planning calculations can help particularize treatments and establish criteria to compare and elect radiation techniques, contributing to the tumor control and the success of the treatment. Accordingly, biological models of cellular response to radiation have to be well established. This work aimed to study the applicability of using biological models in radiotherapy planning calculations to aid evaluating radiotherapy techniques. Tumor control probability (TCP) was studied for two formulations of the linear-quadratic model, with and without repopulation, as a function of planning parameters, as dose per fraction, and of radiobiological parameters, as the α/β ratio. Besides, the usage of biological criteria to compare radiotherapy techniques was tested using a prostate planning simulated with Monte Carlo code PENELOPE. Afterwards, prostate planning for five patients from the Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto, USP, using three different techniques were compared using the tumor control probability. In that order, dose matrices from the XiO treatment planning system were converted to TCP distributions and TCP-volume histograms. The studies performed allow the conclusions that radiobiological parameters can significantly influence tumor control

  7. Application of cybernetic methods in physics

    International Nuclear Information System (INIS)

    Basic aspects of the subject and methodology for a new and rapidly developing area of research that has emerged at the intersection of physics and control theory (cybernetics) and emphasizes the application of cybernetic methods to the study of physical systems are reviewed. Speed-gradient and Hamiltonian solutions for energy control problems in conservative and dissipative systems are presented. Application examples such as the Kapitza pendulum, controlled overcoming of a potential barrier, and controlling coupled oscillators and molecular systems are presented. A speed-gradient approach to modeling the dynamics of physical systems is discussed. (reviews of topical problems)

  8. Methods for analysis of fluoroquinolones in biological fluids

    Science.gov (United States)

    Methods for analysis of 10 selected fluoroquinolone antibiotics in biological fluids are reviewed. Approaches for sample preparation, detection methods, limits of detection and quantitation and recovery information are provided for both single analyte and multi-analyte fluoroquinolone methods....

  9. Physical acoustics v.8 principles and methods

    CERN Document Server

    Mason, Warren P

    1971-01-01

    Physical Acoustics: Principles and Methods, Volume VIII discusses a number of themes on physical acoustics that are divided into seven chapters. Chapter 1 describes the principles and applications of a tool for investigating phonons in dielectric crystals, the spin phonon spectrometer. The next chapter discusses the use of ultrasound in investigating Landau quantum oscillations in the presence of a magnetic field and their relation to the strain dependence of the Fermi surface of metals. The third chapter focuses on the ultrasonic measurements that are made by pulsing methods with velo

  10. Geometric Methods in Physics : XXXIII Workshop

    CERN Document Server

    Bieliavsky, Pierre; Odzijewicz, Anatol; Schlichenmaier, Martin; Voronov, Theodore

    2015-01-01

    This book presents a selection of papers based on the XXXIII Białowieża Workshop on Geometric Methods in Physics, 2014. The Białowieża Workshops are among the most important meetings in the field and attract researchers from both mathematics and physics. The articles gathered here are mathematically rigorous and have important physical implications, addressing the application of geometry in classical and quantum physics. Despite their long tradition, the workshops remain at the cutting edge of ongoing research. For the last several years, each Białowieża Workshop has been followed by a School on Geometry and Physics, where advanced lectures for graduate students and young researchers are presented; some of the lectures are reproduced here. The unique atmosphere of the workshop and school is enhanced by its venue, framed by the natural beauty of the Białowieża forest in eastern Poland. The volume will be of interest to researchers and graduate students in mathematical physics, theoretical physics and m...

  11. Experimental Method to Determine Some Physical Properties in Physics Classes

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Pires

    2015-10-01

    Full Text Available ABSTRACT Particle density, gravimetric and volumetric water contents and porosity are important basic concepts to characterize porous systems such as soils. This paper presents a proposal of an experimental method to measure these physical properties, applicable in experimental physics classes, in porous media samples consisting of spheres with the same diameter (monodisperse medium and with different diameters (polydisperse medium. Soil samples are not used given the difficulty of working with this porous medium in laboratories dedicated to teaching basic experimental physics. The paper describes the method to be followed and results of two case studies, one in monodisperse medium and the other in polydisperse medium. The particle density results were very close to theoretical values for lead spheres, whose relative deviation (RD was -2.9 % and +0.1 % RD for the iron spheres. The RD of porosity was also low: -3.6 % for lead spheres and -1.2 % for iron spheres, in the comparison of procedures – using particle and porous medium densities and saturated volumetric water content – and monodisperse and polydisperse media.

  12. Biological mechanisms underlying the role of physical fitness in health and resilience

    OpenAIRE

    Silverman, Marni N.; Deuster, Patricia A.

    2014-01-01

    Physical fitness, achieved through regular exercise and/or spontaneous physical activity, confers resilience by inducing positive psychological and physiological benefits, blunting stress reactivity, protecting against potentially adverse behavioural and metabolic consequences of stressful events and preventing many chronic diseases. In this review, we discuss the biological mechanisms underlying the beneficial effects of physical fitness on mental and physical health. Physical fitness appear...

  13. Physics and mathematical tools methods and examples

    CERN Document Server

    Alastuey, Angel; Magro, Marc; Pujol, Pierre

    2016-01-01

    This book presents mathematical methods and tools which are useful for physicists and engineers: response functions, Kramers-Kronig relations, Green's functions, saddle point approximation. The derivations emphasize the underlying physical arguments and interpretations without any loss of rigor. General introductions describe the main features of the methods, while connections and analogies between a priori different problems are discussed. They are completed by detailed applications in many topics including electromagnetism, hydrodynamics, statistical physics, quantum mechanics, etc. Exercises are also proposed, and their solutions are sketched. A self-contained reading of the book is favored by avoiding too technical derivations, and by providing a short presentation of important tools in the appendices. It is addressed to undergraduate and graduate students in physics, but it can also be used by teachers, researchers and engineers.

  14. Biologic: Gene circuits and feedback in an introductory physics sequence for biology and premedical students

    CERN Document Server

    Cahn, S B

    2013-01-01

    Two synthetic gene circuits -- the genetic toggle switch and the repressilator -- are analyzed quantitatively and discussed in the context of an educational module on gene circuits and feedback that constitutes the final topic of a year-long introductory physics sequence, aimed at biology and premedical undergraduate students. The genetic toggle switch consists of two genes, each of whose protein product represses the other's expression, while the repressilator consists of three genes, each of whose protein product represses the next gene's expression. Analytic, numerical, and electronic treatments of the genetic toggle switch shows that this gene circuit realizes bistability. A simplified treatment of the repressilator reveals that this circuit can realize sustained oscillations. In both cases, a "phase diagram" is obtained, that specifies the region of parameter space in which bistability or oscillatory behavior, respectively, occurs.

  15. Energy and Matter: Differences in Discourse in Physical and Biological Sciences Can Be Confusing for Introductory Biology Students

    Science.gov (United States)

    Hartley, Laurel M.; Momsen, Jennifer; Maskiewicz, April; D'Avanzo, Charlene

    2012-01-01

    Biology majors often take introductory biology, chemistry, and physics courses during their first two years of college. The various and sometimes conflicting discourse about and explanations of matter and energy in these courses may contribute to confusion and alternative conceptions (those that differ from scientific consensus) in biology…

  16. Elimination of cerium-144 - physical and biological characteristics

    International Nuclear Information System (INIS)

    The decontamination efficiency of the preparation pentacyn (CaNa3-DTPA) with regard to radiocerium was evaluated. Investigated were not only physical parameters (radionuclide kinetics, absorbed doses decrease), but also morphological and biochemical indexes. Four groups of male Wistar rats were treated accordingly with 144Ce; 144Ce + pentacyn; external irrradiation + 144Ce; external irradiation + 144Ce + pentacyn. External gamma irradiation was performed with a dose of 260 cGy, 144Ce (1480 kBq/animal) was introduced intratarcheally 1 h after external irradiation. Pentacyn was administred according to the following scheme, ensuring maximal efficiency and minimal toxicity: intratracheally administration 30 min after radionuclide intake by 0.2 ml and subsequent intraperitoneally applications on days 1, 3, 5, 7, 10 and 17 by 0.5 ml. Determined were the following parameters characterizing the development of fibrous process: the quantity of oxyproline in collagen, the quantity of hexosamine in lung tissues, the changes in dry mass and heart camera index. It was concluded that biological criteria are important component of the decontamination efficiency evaluation

  17. Apparatus and Methods for Manipulation and Optimization of Biological Systems

    Science.gov (United States)

    Ho, Chih-Ming (Inventor); Wong, Pak Kin (Inventor); Sun, Ren (Inventor); Yu, Fuqu (Inventor)

    2014-01-01

    The invention provides systems and methods for manipulating biological systems, for example to elicit a more desired biological response from a biological sample, such as a tissue, organ, and/or a cell. In one aspect, the invention operates by efficiently searching through a large parametric space of stimuli and system parameters to manipulate, control, and optimize the response of biological samples sustained in the system. In one aspect, the systems and methods of the invention use at least one optimization algorithm to modify the actuator's control inputs for stimulation, responsive to the sensor's output of response signals. The invention can be used, e.g., to optimize any biological system, e.g., bioreactors for proteins, and the like, small molecules, polysaccharides, lipids, and the like. Another use of the apparatus and methods includes is for the discovery of key parameters in complex biological systems.

  18. Evaluation of methods to assess physical activity

    Science.gov (United States)

    Leenders, Nicole Y. J. M.

    Epidemiological evidence has accumulated that demonstrates that the amount of physical activity-related energy expenditure during a week reduces the incidence of cardiovascular disease, diabetes, obesity, and all-cause mortality. To further understand the amount of daily physical activity and related energy expenditure that are necessary to maintain or improve the functional health status and quality of life, instruments that estimate total (TDEE) and physical activity-related energy expenditure (PAEE) under free-living conditions should be determined to be valid and reliable. Without evaluation of the various methods that estimate TDEE and PAEE with the doubly labeled water (DLW) method in females there will be eventual significant limitations on assessing the efficacy of physical activity interventions on health status in this population. A triaxial accelerometer (Tritrac-R3D, (TT)), an uniaxial (Computer Science and Applications Inc., (CSA)) activity monitor, a Yamax-Digiwalker-500sp°ler , (YX-stepcounter), by measuring heart rate responses (HR method) and a 7-d Physical Activity Recall questionnaire (7-d PAR) were compared with the "criterion method" of DLW during a 7-d period in female adults. The DLW-TDEE was underestimated on average 9, 11 and 15% using 7-d PAR, HR method and TT. The underestimation of DLW-PAEE by 7-d PAR was 21% compared to 47% and 67% for TT and YX-stepcounter. Approximately 56% of the variance in DLW-PAEE*kgsp{-1} is explained by the registration of body movement with accelerometry. A larger proportion of the variance in DLW-PAEE*kgsp{-1} was explained by jointly incorporating information from the vertical and horizontal movement measured with the CSA and Tritrac-R3D (rsp2 = 0.87). Although only a small amount of variance in DLW-PAEE*kgsp{-1} is explained by the number of steps taken per day, because of its low cost and ease of use, the Yamax-stepcounter is useful in studies promoting daily walking. Thus, studies involving the

  19. A General Symbolic Method with Physical Applications

    CERN Document Server

    Smith, G M

    2000-01-01

    A solution to the problem of unifying the General Relativistic and Quantum Theoretical formalisms is given which introduces a new non-axiomatic symbolic method and an algebraic generalization of the Calculus to non-finite symbolisms without reference to the concept of a limit. An essential feature of the non-axiomatic method is the inadequacy of any (finite) statements: Identifying this aspect of the theory with the "existence of an external physical reality" both allows for the consistency of the method with the results of experiments and avoids the so-called "measurement problem" of quantum theory.

  20. PHYSICAL METHODS IN AGRO-FOOD CHAIN

    Directory of Open Access Journals (Sweden)

    ANNA ALADJADJIYAN

    2009-06-01

    Full Text Available Chemical additives (fertilizers and plant protection preparations are largely used for improving the production yield of food produce. Their application often causes the contamination of raw materials for food production, which can be dangerous for the health of consumers. Alternative methods are developed and implemented to improve and ensure the safety of on-farm production. The substitution of chemical fertilizers and soil additives with alternative treatment methods, such as irradiation, ultrasound and the use of electromagnetic energy are discussed. Successful application of physical methods in different stages of food-preparation is recommended.

  1. Mathematical methods in engineering and physics

    CERN Document Server

    Felder, Gary N

    2016-01-01

    This text is intended for the undergraduate course in math methods, with an audience of physics and engineering majors. As a required course in most departments, the text relies heavily on explained examples, real-world applications and student engagement. Supporting the use of active learning, a strong focus is placed upon physical motivation combined with a versatile coverage of topics that can be used as a reference after students complete the course. Each chapter begins with an overview that includes a list of prerequisite knowledge, a list of skills that will be covered in the chapter, and an outline of the sections. Next comes the motivating exercise, which steps the students through a real-world physical problem that requires the techniques taught in each chapter.

  2. Mathematical Methods for Geophysics and Space Physics

    Science.gov (United States)

    Newman, William I.

    2016-05-01

    Graduate students in the natural sciences - including not only geophysics and space physics but also atmospheric and planetary physics, ocean sciences, and astronomy - need a broad-based mathematical toolbox to facilitate their research. In addition, they need to survey a wider array of mathematical methods that, while outside their particular areas of expertise, are important in related ones. While it is unrealistic to expect them to develop an encyclopedic knowledge of all the methods that are out there, they need to know how and where to obtain reliable and effective insights into these broader areas. Here at last is a graduate textbook that provides these students with the mathematical skills they need to succeed in today's highly interdisciplinary research environment. This authoritative and accessible book covers everything from the elements of vector and tensor analysis to ordinary differential equations, special functions, and chaos and fractals. Other topics include integral transforms, complex analysis, and inverse theory; partial differential equations of mathematical geophysics; probability, statistics, and computational methods; and much more. Proven in the classroom, Mathematical Methods for Geophysics and Space Physics features numerous exercises throughout as well as suggestions for further reading. * Provides an authoritative and accessible introduction to the subject * Covers vector and tensor analysis, ordinary differential equations, integrals and approximations, Fourier transforms, diffusion and dispersion, sound waves and perturbation theory, randomness in data, and a host of other topics * Features numerous exercises throughout * Ideal for students and researchers alike * An online illustration package is available to professors

  3. Improved core physics test method at HZP

    International Nuclear Information System (INIS)

    In case of 3 loop nuclear plants in Korea, the error of control rod worth measurement which is one item of core physics test at HZP is increased considerably compared with previous cycle data since loading of V5H. The cause of error increase of control rod worth and the reactivity effect according to flux and background level are analyzed. The root cause of error increment is that the flux level which is detected by excore detector is decreased by applying low-low leakage or ultra low leakage loading pattern and the background level is increased due to reduction of planned outage and longer fuel cycle length. In current test method, it is limited to decrease or eliminate the effect of background. This is confirmed based on the data of physics test for Ulchin 1 cycle 9. In order to perform credible core physics test at HZP at this circumstance, the elimination of such background effect is reviewed and setup by adjusting electrometer used in reactivity computer by compensating the amount of background level. Therefore the improved core physics test method to perform the credible test at HZP is setup by this study regardless of any kind of loading pattern and cycle scheme

  4. Quantum integrable systems. Quantitative methods in biology

    CERN Document Server

    Feverati, Giovanni

    2011-01-01

    Quantum integrable systems have very strong mathematical properties that allow an exact description of their energetic spectrum. From the Bethe equations, I formulate the Baxter "T-Q" relation, that is the starting point of two complementary approaches based on nonlinear integral equations. The first one is known as thermodynamic Bethe ansatz, the second one as Kl\\"umper-Batchelor-Pearce-Destri- de Vega. I show the steps toward the derivation of the equations for some of the models concerned. I study the infrared and ultraviolet limits and discuss the numerical approach. Higher rank integrals of motion can be obtained, so gaining some control on the eigenvectors. After, I discuss the Hubbard model in relation to the N = 4 supersymmetric gauge theory. The Hubbard model describes hopping electrons on a lattice. In the second part, I present an evolutionary model based on Turing machines. The goal is to describe aspects of the real biological evolution, or Darwinism, by letting evolve populations of algorithms. ...

  5. Perspectives in biological physics: the nDDB project for a neutron Dynamics Data Bank for biological macromolecules.

    Science.gov (United States)

    Rusevich, Leonid; García Sakai, Victoria; Franzetti, Bruno; Johnson, Mark; Natali, Francesca; Pellegrini, Eric; Peters, Judith; Pieper, Jörg; Weik, Martin; Zaccai, Giuseppe

    2013-07-01

    Neutron spectroscopy provides experimental data on time-dependent trajectories, which can be directly compared to molecular dynamics simulations. Its importance in helping us to understand biological macromolecules at a molecular level is demonstrated by the results of a literature survey over the last two to three decades. Around 300 articles in refereed journals relate to neutron scattering studies of biological macromolecular dynamics, and the results of the survey are presented here. The scope of the publications ranges from the general physics of protein and solvent dynamics, to the biologically relevant dynamics-function relationships in live cells. As a result of the survey we are currently setting up a neutron Dynamics Data Bank (nDDB) with the aim to make the neutron data on biological systems widely available. This will benefit, in particular, the MD simulation community to validate and improve their force fields. The aim of the database is to expose and give easy access to a body of experimental data to the scientific community. The database will be populated with as much of the existing data as possible. In the future it will give value, as part of a bigger whole, to high throughput data, as well as more detailed studies. A range and volume of experimental data will be of interest in determining how quantitatively MD simulations can reproduce trends across a range of systems and to what extent such trends may depend on sample preparation and data reduction and analysis methods. In this context, we strongly encourage researchers in the field to deposit their data in the nDDB. PMID:23884625

  6. Physical and biological dosimetry for risk perception in radioprotection

    Directory of Open Access Journals (Sweden)

    Ademir Amaral

    2005-10-01

    Full Text Available The increase in ionizing radiation (IR applications, especially nuclear, has been followed by the growth of public concern for the potential associated risks. The public’s perception of such risks is often based on the philosophy that IR is harmful at any exposure level. On the other hand, although radiation workers have knowledge about the nature of IR and its potential health effects, the relationship between absorbed dose and risk is not well understood, principally for low doses. This report presents an overview of physical and biological dosimetry as complementary methodologies, as well as their possible contribution for improving risk perception in radioprotection.O crescente aumento das aplicações das radiações ionizantes, em particular as radiações de origem nuclear, tem sido acompanhado pelo aumento do interesse público em relação aos riscos associados a essas aplicações. A percepção de tais riscos por parte da população é freqüentemente baseada na filosofia que a radiação ionizante é perigosa independentemente dos níveis de exposição. Por outro lado, apesar dos trabalhadores ocupacionalmente expostos terem conhecimento da natureza da IR e seus possíveis efeitos á saúde, a relação entre dose absorvida e risco não é bem entendida por estes, em particular para baixos valores de dose. Este artigo resume aspectos da dosimetria física e biológica como metodologias complementares na melhoria da percepção dos riscos em radioproteção.

  7. The banker plant method in biological control

    NARCIS (Netherlands)

    Huang, N.; Enkegaard, A.; Osborne, L.S.; Ramakers, P.M.J.; Messelink, G.J.; Pijnakker, J.; Murphy, G.

    2011-01-01

    In the banker plant method, long-lasting rearing units for beneficials are created in the crop by distributing plants infested with herbivores or carrying other food items, such as pollen. The method has been widely investigated over many years and used to aid establishment, development and dispersa

  8. Physical characterization methods for supplementary cementitious materials

    OpenAIRE

    Arvaniti, Eleni; Juenger, Maria; Bernal, Susan; Duchesne, Josée; Courard, Luc; Leroy, Sophie; Provis, John; Klemm, Agnieska; De Belie, Nele

    2015-01-01

    The main supplementary cementitious materials (SCMs) that are used today are industrial by-products. In most cases the quality of these materials cannot be controlled during their production, resulting in materials with varied characteristics. The adequate physical characterization of SCMs is important to better predict their performance and optimize their use in concretes production. There are standardized methods used to determine the particle characteristics for Portland cements that are u...

  9. An Improved Method for Completely Uncertain Biological Network Alignment

    OpenAIRE

    2015-01-01

    With the continuous development of biological experiment technology, more and more data related to uncertain biological networks needs to be analyzed. However, most of current alignment methods are designed for the deterministic biological network. Only a few can solve the probabilistic network alignment problem. However, these approaches only use the part of probabilistic data in the original networks allowing only one of the two networks to be probabilistic. To overcome the weakness of curr...

  10. Advanced Systems Biology Methods in Drug Discovery and Translational Biomedicine

    OpenAIRE

    Jun Zou; Ming-Wu Zheng; Gen Li; Zhi-Guang Su

    2013-01-01

    Systems biology is in an exponential development stage in recent years and has been widely utilized in biomedicine to better understand the molecular basis of human disease and the mechanism of drug action. Here, we discuss the fundamental concept of systems biology and its two computational methods that have been commonly used, that is, network analysis and dynamical modeling. The applications of systems biology in elucidating human disease are highlighted, consisting of human disease networ...

  11. The generator coordinate method in nuclear physics

    International Nuclear Information System (INIS)

    The generator coordinate method is introduced as a physical description of a N-body system in a subspace of a reduced number of degrees of freeedom. Special attention is placed on the identification of these special, 'collective' degrees of freedom. It is shown in particular that the method has close links with the Born-Oppenheimer approximation and also that considerations of differential geometry are useful in the theory. A set of applications is discussed and in particular the case of nuclear collisions is considered

  12. 8. International Conference on Pulse Investigations in Chemistry, Biology and Physics - PULS'2008. Abstracts

    International Nuclear Information System (INIS)

    The Report comprises abstracts of 68 communications (oral and posters) presented during the 8. International Conference on Pulse Investigations in Chemistry, Biology and Physics - PULS'2008, held on September 6 - 12, 2008 in Cracow. Presentations cover a variety of research fields representing different fields of pulse radiolysis in chemistry, biology and physics

  13. Geometric Methods in Physics : XXXII Workshop

    CERN Document Server

    Bieliavsky, Pierre; Odesskii, Alexander; Odzijewicz, Anatol; Schlichenmaier, Martin; Voronov, Theodore; Geometric Methods in Physics

    2014-01-01

    The Białowieża Workshops on Geometric Methods in Physics, which are hosted in the unique setting of the Białowieża natural forest in Poland, are among the most important meetings in the field. Every year some 80 to 100 participants from both the mathematics and physics world join to discuss new developments and to exchange ideas. The current volume was produced on the occasion of the 32nd meeting in 2013. It is now becoming a tradition that the Workshop is followed by a School on Geometry and Physics, which consists of advanced lectures for graduate students and young researchers. Selected speakers at the 2013 Workshop were asked to contribute to this book, and their work was supplemented by additional review articles. The selection shows that, despite its now long tradition, the workshop remains at the cutting edge of research. The 2013 Workshop also celebrated the 75th birthday of Daniel Sternheimer, and on this occasion the discussion mainly focused on his contributions to mathematical physics such as ...

  14. Some biological side effects in laboratories of the plasma physics and nuclear fusion research school of Iran

    OpenAIRE

    Shervin Goudarzi; Mina Jafarabadi; Fatemeh Nejad

    2010-01-01

    Objective: Reporting some biological side effects with special attention to reproductive points which were seen after different experiments in laboratories of the Plasma Physics & Nuclear Fusion in atomic energy organization of Iran.Materials and methods: Dosimeter analysis and interpretation of biological side effects of research studies in nuclear fusion laboratories.Results: In the last 3 decades, neglecting the principles of the radiation protection has been confirmed in laboratories ...

  15. Biologically Inspired Optimization Methods An Introduction

    CERN Document Server

    Wahde, M

    2008-01-01

    The advent of rapid, reliable and cheap computing power over the last decades has transformed many, if not most, fields of science and engineering. The multidisciplinary field of optimization is no exception. First of all, with fast computers, researchers and engineers can apply classical optimization methods to problems of larger and larger size. In addition, however, researchers have developed a host of new optimization algorithms that operate in a rather different way than the classical ones, and that allow practitioners to attack optimization problems where the classical methods are either

  16. [Period-tripling in Multiscale Physical and Biological Events].

    Science.gov (United States)

    Bondar, A T; Fedorov, M V; Kolombet, V A

    2015-01-01

    A recent paper by S.J. Puetz et al. (Chaos, Solitons -& Fractals, v. 62-63, p. 55, 2014) described a fundamental period-tripled model. It involves periods of different astronomical (quasars, Sun), geophysical (geomagnetic, climatic, volcanic) and some biological processes. This work contains statistics for sixteen pairs of a period-tripled sequence. These periods range from -50 years to 1.5 billion years and no signs of the timescale limitations are found. We believe that the universal scope of the fundamental period-tripled model can be used for the development of new methodology of research data analysis: the main idea is that the spectrum of the periods of the studied event should be tested for the similarity with the spectrum of fundamental period-tripling pattern (because of the fundamental nature of the period-tripled model). Using this method, in this study we complement an already described period-tripled model with periods of human memory performance ranging from one minute to one month also adding seven relevant periods/frequencies of the period-tripled model in the range of human hearing. We make a conclusion that these characteristic frequencies may form the basis for music and singing phenomena. The new methodology is particularly appropriate for being applied in medicine and engineering. PMID:26841519

  17. Nitric oxide methods in seed biology

    Science.gov (United States)

    Nitric oxide (NO) is a gaseous, free radical that is involved in many aspects of plant growth, development, and responses to the environment. Compelling evidence points to a central role for NO in the loss of seed dormancy. NO is highly reactive, toxic at high concentrations, and unstable. Methods f...

  18. Leveraging a relationship with biology to expand a relationship with physics

    Science.gov (United States)

    Sawtelle, Vashti; Turpen, Chandra

    2016-06-01

    This work examines how experiences in one disciplinary domain (biology) can impact the relationship a student builds with another domain (physics). We present a model for disciplinary relationships using the constructs of identity, affect, and epistemology. With these constructs we examine an ethnographic case study of a student who experienced a significant shift in her relationship with physics. We describe how this shift demonstrates (i) a stronger identification with physics, (ii) a more mixed affective stance towards physics, and (iii) more expertlike ways of knowing in physics. We argue that recruiting the student's relationship with biology into experiences of learning physics impacted her relationship with physics as well as her sense of how physics and biology are linked.

  19. Carbonate Beaches: A Balance Between Biological and Physical Processes

    Science.gov (United States)

    Nairn, R.; Risk, M.

    2004-12-01

    Carbonate beaches are a unique example of the interaction between biological processes, creating the sediments, and physical processes, moving and often removing the sediments. On the sediment supply side, carbonate sediments are born, not made. They exist in dynamic equilibrium between production and destruction. Following the creation of carbonate sediment in coral reef and lagoon environments, the sediments are moved shoreward to the beach, transport along the shore and sometimes, eventually lost offshore, often as the result of tropical storms. Comprehensive studies of the balance between the supply and loss of carbonate sediments and beach dynamics have been completed for the islands of Mauritius and Barbados. Field studies and remote sensing (Compact Airborne Spectrometry Imaging) have been applied to develop carbonate sediment production rates for a range of reef and lagoon conditions. Using GIS, these production rates have been integrated to determine sediment supply rates for different segments of the coastline. 1-D and 2-D models of waves, hydrodynamics, sediment transport and morphodynamics were set-up and tested against observed beach response to storm events or a sequence of storm events. These complex deterministic models are not suitable for application over periods of decades. However, it was possible to characterize storm events by the extent of sand loss, and relate this to key descriptive factors for groups of storm events, thereby encapsulating the erosion response. A long-term predictive tool for evaluating beach erosion and accretion response, over a period of several decades, was developed by combining the supply rates for carbonate sediment and the encapsulated representation of the loss rates through physical processes. The ability of this predictive tool was successfully tested against observed long term beach evolution along sections of the coast in Barbados and Mauritius using air photo analysis in GIS for shoreline change over periods

  20. Comparison of Career Concerns among College Women and Men Enrolled in Biological and Physical Sciences

    Science.gov (United States)

    Dodson, Maria

    The underrepresentation of women enrolled in the physical sciences continues to challenge academic leaders despite over 40 years of programming to promote gender equity within these curricula. This study employed a quantitative, causal comparative method to explore if and to what extent career concerns differed among female and male undergraduate physical and biological science students. The theory of planned behavior and life-span, life-space theory served as the theoretical framework for the study. Quantitative survey data were collected from 43 students at four institutions across the United States. The findings indicated that undergraduate women in physical science programs of study had a significantly different level of concern about the Innovating sub-category of the third stage of career development, Maintenance, as compared to undergraduate women in biological science curricula [F(1,33) = 6.244, p = 0.018]. Additionally, there was a statistically significant difference between female undergraduate physical science students and undergraduate male science students in the sub-categories of Implementation [F(1,19) = 7.228, p = 0.015], Advancing [F(1,19) = 11.877, p = 0.003], and Innovating [F(1,19) = 11.782, p = 0.003] within the first three stages of career development (Exploration, Establishment, and Maintenance). The comparative differences among the study groups offers new information about undergraduate career concerns that may contribute to the underrepresentation of women enrolled in the physical sciences. Suggestions for future research and programs within higher education targeted at reducing the career concerns of current and prospective female students in physical science curricula are discussed.

  1. Bringing the physical sciences into your cell biology research

    OpenAIRE

    Robinson, Douglas N; Iglesias, Pablo A.

    2012-01-01

    Historically, much of biology was studied by physicists and mathematicians. With the advent of modern molecular biology, a wave of researchers became trained in a new scientific discipline filled with the language of genes, mutants, and the central dogma. These new molecular approaches have provided volumes of information on biomolecules and molecular pathways from the cellular to the organismal level. The challenge now is to determine how this seemingly endless list of components works toget...

  2. Novel computational biology methods and their applications to drug discovery

    Institute of Scientific and Technical Information of China (English)

    Sharangdhar S. PHATAK; Hoang T. TRAN; Shuxing ZHANG

    2011-01-01

    Computational biology methods are now firmly entrenched in the drug discovery process.These methods focus on modeling and simulations of biological systems to complement and direct conventional experimental approaches.Two important branches of computational biology include protein homology modeling and the computational biophysics method of molecular dynamics.Protein modeling methods attempt to accurately predict three-dimensional (3D) structures of uncrystallized proteins for subsequent structure-based drug design applications.Molecular dynamics methods aim to elucidate the molecular motions of the static representations of crystallized protein structures.In this review we highlight recent novel methodologies in the field of homology modeling and molecular dynamics.Selected drug discovery applications using these methods conclude the review.

  3. Register indicators of physical endurance of biological objects when running a treadmill and swimming with weights using computer video markerless tracking

    OpenAIRE

    Datsenko A.V.

    2014-01-01

    Purpose: to study the use of video tracking to assess physical endurance and indicators of biological objects fatigue when running on a treadmill and swimming with the load. Material and methods. Physical endurance evaluated by test facilities for running on a treadmill and swimming with the load. As the object of the studies used laboratory rats. Results. For indicators of physical endurance biological objects isolated areas running track of treadmill and electrical stimulation site, when sw...

  4. Breakthrough Propulsion Physics Project: Project Management Methods

    Science.gov (United States)

    Millis, Marc G.

    2004-01-01

    To leap past the limitations of existing propulsion, the NASA Breakthrough Propulsion Physics (BPP) Project seeks further advancements in physics from which new propulsion methods can eventually be derived. Three visionary breakthroughs are sought: (1) propulsion that requires no propellant, (2) propulsion that circumvents existing speed limits, and (3) breakthrough methods of energy production to power such devices. Because these propulsion goals are presumably far from fruition, a special emphasis is to identify credible research that will make measurable progress toward these goals in the near-term. The management techniques to address this challenge are presented, with a special emphasis on the process used to review, prioritize, and select research tasks. This selection process includes these key features: (a) research tasks are constrained to only address the immediate unknowns, curious effects or critical issues, (b) reliability of assertions is more important than the implications of the assertions, which includes the practice where the reviewers judge credibility rather than feasibility, and (c) total scores are obtained by multiplying the criteria scores rather than by adding. Lessons learned and revisions planned are discussed.

  5. Does Taking Physics Pay Off Later in Chemistry and Biology Courses?

    Science.gov (United States)

    Sadler, Philip M.; Tai, R. H.

    2006-12-01

    The relationship between performance of 8474 students enrolled in introductory college biology, chemistry, or physics courses and their prior high school course-taking in physics is investigated in 122 randomly-selected undergraduate classrooms. Employing multiple linear regression, models are constructed that control for variation in student background, socio-economic status, and students' prior achievement in mathematics and English. A small effect size (ES = 0.13 SD, p = 0.01) is found for each year of school coursework in the same subject as a college course in biology, chemistry, or physics. No statistically significant relationship is found (p = 0.05) for any cross-disciplinary preparation, including that of differing amounts of high school physics preparation on college chemistry or biology performance. Our findings do not provide support for the view that students will be better prepared for taking high school chemistry and biology by taking physics in ninth grade.

  6. The method validation step of biological dosimetry accreditation process

    International Nuclear Information System (INIS)

    One of the missions of the Laboratory of Biological Dosimetry (L.D.B.) of the Institute for Radiation and Nuclear Safety (I.R.S.N.) is to assess the radiological dose after an accidental overexposure suspicion to ionising radiation, by using radio-induced changes of some biological parameters. The 'gold standard' is the yield of dicentrics observed in patients lymphocytes, and this yield is converted in dose using dose effect relationships. This method is complementary to clinical and physical dosimetry, for medical team in charge of the patients. To obtain a formal recognition of its operational activity, the laboratory decided three years ago, to require an accreditation, by following the recommendations of both 17025 General Requirements for the Competence of Testing and Calibration Laboratories and 19238 Performance criteria for service laboratories performing biological dosimetry by cyto-genetics. Diagnostics, risks analysis were realized to control the whole analysis process leading to documents writing. Purchases, personnel department, vocational training were also included in the quality system. Audits were very helpful to improve the quality system. One specificity of this technique is that it is not normalized therefore apart from quality management aspects, several technical points needed some validations. An inventory of potentially influent factors was carried out. To estimate their real effect on the yield of dicentrics, a Placket-Burman experimental design was conducted. The effect of seven parameters was tested: the BUdr (bromodeoxyuridine), PHA (phytohemagglutinin) and colcemid concentration, the culture duration, the incubator temperature, the blood volume and the medium volume. The chosen values were calculated according to the uncertainties on the way they were measured i.e. pipettes, thermometers, test tubes. None of the factors has a significant impact on the yield of dicentrics. Therefore the uncertainty linked to their use was considered as

  7. Innovative quantum technologies for microgravity fundamental physics and biological research

    Science.gov (United States)

    Kierk, I. K.

    2002-01-01

    This paper presents a new technology program, within the fundamental physics, focusing on four quantum technology areas: quantum atomics, quantum optics, space superconductivity and quantum sensor technology, and quantum field based sensor and modeling technology.

  8. Single Molecule Spectroscopy in Chemistry, Physics and Biology Nobel Symposium

    CERN Document Server

    Gräslund, Astrid; Widengren, Jerker

    2010-01-01

    Written by the leading experts in the field, this book describes the development and current state-of-the-art in single molecule spectroscopy. The application of this technique, which started 1989, in physics, chemistry and biosciences is displayed.

  9. Current laboratory methods for biological threat agent identification.

    Science.gov (United States)

    Henchal, E A; Teska, J D; Ludwig, G V; Shoemaker, D R; Ezzell, J W

    2001-09-01

    The authors present an integrated approach for the identification of biological threat agents. The methods used have been used extensively in field exercises and during response to incidents of biological terrorism. A diagnostic system, which integrates the clinical diagnosis or medical intelligence with immunodiagnostic tests, rapid gene amplification assays, and standard culture, provides results of the highest quality and confidence. In the future, selected reagents and technologies will be distributed through a network of civilian and military laboratories. PMID:11572145

  10. Biological Effectiveness and Application of Heavy Ions in Radiation Therapy Described by a Physical and Biological Model

    DEFF Research Database (Denmark)

    Olsen, Kjeld J.; Hansen, Johnny W.

    A description is given of the physical basis for applying track structure theory in the determination of the effectiveness of heavy-ion irradiation of single- and multi-hit target systems. It will be shown that for applying the theory to biological systems the effectiveness of heavy-ion irradiation......-LET radiation applied simultaneously in therapy....

  11. An Optimal Classification Method for Biological and Medical Data

    OpenAIRE

    Yu-Chien Ko; Hao-Chun Lu; Yao-Huei Huang

    2012-01-01

    This paper proposes a union of hyperspheres by the mixed-integer nonlinear program to classify biological and medical datasets. A classifying program with nonlinear terms uses piecewise linearization technique to obtain a global optimum. The numerical examples illustrate that the proposed method can obtain the global optimum more effectively than current methods.

  12. Quantum mechanical simulation methods for studying biological systems

    International Nuclear Information System (INIS)

    Most known biological mechanisms can be explained using fundamental laws of physics and chemistry and a full understanding of biological processes requires a multidisciplinary approach in which all the tools of biology, chemistry and physics are employed. An area of research becoming increasingly important is the theoretical study of biological macromolecules where numerical experimentation plays a double role of establishing a link between theoretical models and predictions and allowing a quantitative comparison between experiments and models. This workshop brought researchers working on different aspects of the development and application of quantum mechanical simulation together, assessed the state-of-the-art in the field and highlighted directions for future research. Fourteen lectures (theoretical courses and specialized seminars) deal with following themes: 1) quantum mechanical calculations of large systems, 2) ab initio molecular dynamics where the calculation of the wavefunction and hence the energy and forces on the atoms for a system at a single nuclear configuration are combined with classical molecular dynamics algorithms in order to perform simulations which use a quantum mechanical potential energy surface, 3) quantum dynamical simulations, electron and proton transfer processes in proteins and in solutions and finally, 4) free seminars that helped to enlarge the scope of the workshop. (N.T.)

  13. Alternative statistical methods for cytogenetic radiation biological dosimetry

    CERN Document Server

    Fornalski, Krzysztof Wojciech

    2014-01-01

    The paper presents alternative statistical methods for biological dosimetry, such as the Bayesian and Monte Carlo method. The classical Gaussian and robust Bayesian fit algorithms for the linear, linear-quadratic as well as saturated and critical calibration curves are described. The Bayesian model selection algorithm for those curves is also presented. In addition, five methods of dose estimation for a mixed neutron and gamma irradiation field were described: two classical methods, two Bayesian methods and one Monte Carlo method. Bayesian methods were also enhanced and generalized for situations with many types of mixed radiation. All algorithms were presented in easy-to-use form, which can be applied to any computational programming language. The presented algorithm is universal, although it was originally dedicated to cytogenetic biological dosimetry of victims of a nuclear reactor accident.

  14. Chemical, physical and biological features of Okra pectin

    OpenAIRE

    Sengkhamparn, N.

    2009-01-01

    In Thailand, many plants have been used as vegetables as well as for traditional medicine. Okra, Abelmoschus esculentus (L.) Moench, is an example of such a plant. Examples for the medical use are treatment of gastric irritation, treatment of dental diseases, lowering cholesterol level and preventing cancer. These biological activities are ascribed to polysaccharide structures of okra in particular pectin structures. However, the precise structure of okra pectins and also of other polysacchar...

  15. Radiation physics, biophysics and radiation biology. Progress report, October 1, 1980-September 30, 1981

    International Nuclear Information System (INIS)

    Separate abstracts were prepared for the 29 papers in this progress report which deal with radiobiological physics, the biological effects of ionizing radiations, and the modification of these effects by chemical and pharmacological agents

  16. Life sciences: Nuclear medicine, radiation biology, medical physics, 1980-1994. International Atomic Energy Agency Publications

    International Nuclear Information System (INIS)

    The catalogue lists all sales publications of the IAEA dealing with Life Sciences issued during the period 1980-1994. The publications are grouped in the following chapters: Nuclear Medicine (including Radiopharmaceuticals), Radiation Biology and Medical Physics (including Dosimetry)

  17. Gamification in citizen science: Projects in particle physics and synthetic biology

    OpenAIRE

    Jennett, C.; Iacovides, I.; Skands, P.; Shomar, H.; Cox, A. L.

    2013-01-01

    We present two new citizen cyberscience projects that are being developed in the research fields of Particle Physics and Synthetic Biology, and discuss several issues to be considered in relation to the gamification of these projects.

  18. Progress report, Biology and Health Physics Division, July 1 to September 30, 1975

    International Nuclear Information System (INIS)

    Interim results are reported for research in health physics, i.e. dosimetry, detectors, and monitoring; environmental research (limnology, radionuclide migration and kinetics; population research (radiation carcinogenesis, radiation effects in human populations); and biology (radiobiology). (E.C.B.)

  19. Progress report, Biology and Health Physics Division, October 1 to December 31, 1975

    International Nuclear Information System (INIS)

    Interim research results are reported in health physics (dosimetry, monitoring), environmental research, population research (tumor induction in mammals, human health record linkage), and biology (radiobiology of rodents, bacteria, bacteriophage T4, and insects). (E.C.B.)

  20. Progress report, Biology and Health Physics Division, April 1 to June 30, 1975

    International Nuclear Information System (INIS)

    Interim results are reported on research at CRNL in health physics (dosimetry, instrumentation, monitoring); environmental research (limnology, radionuclide migration and kinetics); populaton research (tumor induction in mammals, human health records); and biology (radiobiology, genetic studies). (E.C.B.)

  1. Texture analysis methods for the characterisation of biological and medical images

    Directory of Open Access Journals (Sweden)

    Ştefan Ţălu

    2012-06-01

    Full Text Available Adaptations can be extreme in many cases and they help organisms survive in their habitat or ecological niche. These adaptations can affect their anatomy, ethology or physiology. Anatomical adaptations are physical features such as animal's shape, particularities at the skeleton level, texture of exoskeleton, surface of the skin in animals or cuticula in plants etc. The purpose of this paper is to present a synthesis concerning the texture analysis methods used for the characterisation of biological and medical images. Texture analysis methods of biological and medical images provide noninvasive tools that allow biologists, physicians and researchers the early detection and diagnosis of diseases.

  2. Physical characterization of ultrashort laser pulse drilling of biological tissue

    Energy Technology Data Exchange (ETDEWEB)

    Feit, M.D.; Rubenchik, A.M.; Kim, B.M.; Da Silva, L.D.; Stuart, B.C.; Perry, M.D.

    1997-07-21

    Ultrashort laser pulse ablation removes material with low energy fluence required and minimal collateral damage. The ultimate usefulness of this technology for biomedical applications depends, in part, on characterization of the physical conditions attained and determination of the zone of shockwave and heat affected material in particular tissues. Detailed numerical modeling of the relevant physics (deposition, plasma formation, shockwave generation and propagation, thermal conduction) are providing this information. A wide range of time scales is involved, ranging from picosecond for energy deposition and peak pressure and temperature, to nanosecond for development of shockwave, to microsecond for macroscopic thermophysical response.

  3. Analyzing Students' Understanding of Models and Modeling Referring to the Disciplines Biology, Chemistry, and Physics

    Science.gov (United States)

    Krell, Moritz; Reinisch, Bianca; Krüger, Dirk

    2015-06-01

    In this study, secondary school students' ( N = 617; grades 7 to 10) understanding of models and modeling was assessed using tasks which explicitly refer to the scientific disciplines of biology, chemistry, and physics and, as a control, to no scientific discipline. The students' responses are interpreted as their biology-, chemistry-, and physics-related or general understanding of models and modeling. A subpopulation ( N = 115; one class per grade) was subsequently asked which models they had in mind when answering the tasks referring to biology, chemistry, and physics (open-ended questions). The findings show significant differences between students' biology-, chemistry-, and physics-related understandings of models and modeling. Based on a theoretical framework, the biology-related understanding can be seen as less elaborated than the physics- and chemistry-related understandings. The students' general understanding of models and modeling is located between the biology- and the physics-related understandings. Answers to the open-ended questions indicate that students primarily think about scale and functional models in the context of biology tasks. In contrast, more abstract models (e.g., analogical models, diagrams) were mentioned in relation to chemistry and physics tasks. In sum, the findings suggest that models may be used in a rather descriptive way in biology classes but in a predictive way in chemistry and physics classes. This may explain discipline-specific understandings of models and modeling. Only small differences were found in students' understanding of models and modeling between the different grade levels 7/8 and 9/10.

  4. Estimating Escherichia coli loads in streams based on various physical, chemical, and biological factors

    OpenAIRE

    Dwivedi, Dipankar; Mohanty, Binayak P.; Lesikar, Bruce J.

    2013-01-01

    Microbes have been identified as a major contaminant of water resources. Escherichia coli (E. coli) is a commonly used indicator organism. It is well recognized that the fate of E. coli in surface water systems is governed by multiple physical, chemical, and biological factors. The aim of this work is to provide insight into the physical, chemical, and biological factors along with their interactions that are critical in the estimation of E. coli loads in surface streams. There are various mo...

  5. Computational and Biological Analogies for Understanding Fine-Tuned Parameters in Physics

    OpenAIRE

    Vidal, Clement

    2010-01-01

    In this philosophical paper, we explore computational and biological analogies to address the fine-tuning problem in cosmology. We first clarify what it means for physical constants or initial conditions to be fine-tuned. We review important distinctions such as the dimensionless and dimensional physical constants, and the classification of constants proposed by Levy-Leblond. Then we explore how two great analogies, computational and biological, can give new insights into our problem. This pa...

  6. Assessment of physical protection systems: EVA method

    International Nuclear Information System (INIS)

    CEA's missions in various sectors of activity such as nuclear, defence, industrial contracts and the associated regulatory requirements, make it necessary to develop a strategy in the field of physical protection. In particular, firms having nuclear materials are subject to the July 25, 1980 law no.80-572 on the protection and control of nuclear materials. A holding permit delivered by the regulatory authority is conditioned to the protection by the operator of the nuclear materials used. In France it is the nuclear operator who must demonstrate, in the form of a security study, that potential aggressors would be neutralised before they could escape with the material. To meet these requirements, we have developed methods to assess the vulnerability of our facilities. The EVA method, the French acronym for 'Evaluation de la vulnerabilite des Acces' (access vulnerability system) allows dealing with internal and external threats involving brutal actions. In scenarios relating to external threat, the intruders get past the various barriers of our protection system, attempting to steal a large volume of material in one swoop and then escape. In the case of internal threat, the goal is the same. However, as the intruder usually has access to the material in the scope of his activities, the action begins at the level of the target. Our protection system is based on in-depth defense where the intruders are detected and then delayed in their advance towards their target to allow time for intervention forces to intercept them

  7. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1993--November 30, 1994

    International Nuclear Information System (INIS)

    Research at the Center for Radiological Research is a blend of physics, chemistry and biology and epitomizes the multidisciplinary approach towards understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. To an increasing extent, the focus of attention is on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights from the past year are briefly described

  8. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1993--November 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1994-05-01

    Research at the Center for Radiological Research is a blend of physics, chemistry and biology and epitomizes the multidisciplinary approach towards understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. To an increasing extent, the focus of attention is on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights from the past year are briefly described.

  9. Computational approaches to stochastic systems in physics and biology

    Science.gov (United States)

    Jeraldo Maldonado, Patricio Rodrigo

    In this dissertation, I devise computational approaches to model and understand two very different systems which exhibit stochastic behavior: quantum fluids with topological defects arising during quenches and forcing, and complex microbial communities living and evolving with the gastrointestinal tracts of vertebrates. As such, this dissertation is organized into two parts. In Part I, I create a model for quantum fluids, which incorporates a conservative and dissipative part, and I also allow the fluid to be externally forced by a normal fluid. I use then this model to calculate scaling laws arising from the stochastic interactions of the topological defects exhibited by the modeled fluid while undergoing a quench. In Chapter 2 I give a detailed description of this model of quantum fluids. Unlike more traditional approaches, this model is based on Cell Dynamical Systems (CDS), an approach that captures relevant physical features of the system and allows for long time steps during its evolution. I devise a two step CDS model, implementing both conservative and dissipative dynamics present in quantum fluids. I also couple the model with an external normal fluid field that drives the system. I then validate the results of the model by measuring different scaling laws predicted for quantum fluids. I also propose an extension of the model that also incorporates the excitations of the fluid and couples its dynamics with the dynamics of the condensate. In Chapter 3 I use the above model to calculate scaling laws predicted for the velocity of topological defects undergoing a critical quench. To accomplish this, I numerically implement an algorithm that extracts from the order parameter field the velocity components of the defects as they move during the quench process. This algorithm is robust and extensible to any system where defects are located by the zeros of the order parameter. The algorithm is also applied to a sheared stripe-forming system, allowing the

  10. A Novel Biological Dosimetry Method for Monitoring Occupational Radiation Exposure in Diagnostic and Therapeutic Wards: From Radiation Dosimetry to Biological Effects

    OpenAIRE

    Heydarheydari, S.; Haghparast, A.; Eivazi, M.T.

    2016-01-01

    Background and Objective Professional radiation workers are occupationally exposed to long-term low levels of ionizing radiation. Occupational health hazards from radiation exposure, in a large occupational segment of the population, are of special concern. Biological dosimetry can be performed in addition to physical dosimetry with the aim of individual dose assessment and biological effects. Methods In this biodosimetry study, some hematological parameters have been examined in 40 exposed a...

  11. Group behaviour in physical, chemical and biological systems

    Indian Academy of Sciences (India)

    Cihan Saçlioğlu; Önder Pekcan; Vidyanand Nanjundiah

    2014-04-01

    Groups exhibit properties that either are not perceived to exist, or perhaps cannot exist, at the individual level. Such `emergent’ properties depend on how individuals interact, both among themselves and with their surroundings. The world of everyday objects consists of material entities. These are, ultimately, groups of elementary particles that organize themselves into atoms and molecules, occupy space, and so on. It turns out that an explanation of even the most commonplace features of this world requires relativistic quantum field theory and the fact that Planck’s constant is discrete, not zero. Groups of molecules in solution, in particular polymers (`sols’), can form viscous clusters that behave like elastic solids (`gels’). Sol-gel transitions are examples of cooperative phenomena. Their occurrence is explained by modelling the statistics of inter-unit interactions: the likelihood of either state varies sharply as a critical parameter crosses a threshold value. Group behaviour among cells or organisms is often heritable and therefore can evolve. This permits an additional, typically biological, explanation for it in terms of reproductive advantage, whether of the individual or of the group. There is no general agreement on the appropriate explanatory framework for understanding group-level phenomena in biology.

  12. Group behaviour in physical, chemical and biological systems.

    Science.gov (United States)

    Saçlioğlu, Cihan; Pekcan, Önder; Nanjundiah, Vidyanand

    2014-04-01

    Groups exhibit properties that either are not perceived to exist, or perhaps cannot exist, at the individual level. Such 'emergent' properties depend on how individuals interact, both among themselves and with their surroundings. The world of everyday objects consists of material entities. These are, ultimately, groups of elementary particles that organize themselves into atoms and molecules, occupy space, and so on. It turns out that an explanation of even the most commonplace features of this world requires relativistic quantum field theory and the fact that Planck's constant is discrete, not zero. Groups of molecules in solution, in particular polymers ('sols'), can form viscous clusters that behave like elastic solids ('gels'). Sol-gel transitions are examples of cooperative phenomena. Their occurrence is explained by modelling the statistics of inter-unit interactions: the likelihood of either state varies sharply as a critical parameter crosses a threshold value. Group behaviour among cells or organisms is often heritable and therefore can evolve. This permits an additional, typically biological, explanation for it in terms of reproductive advantage, whether of the individual or of the group. There is no general agreement on the appropriate explanatory framework for understanding group-level phenomena in biology. PMID:24736152

  13. The application of statistical physics to evolutionary biology

    OpenAIRE

    Sella, Guy; Hirsh, Aaron E

    2005-01-01

    A number of fundamental mathematical models of the evolutionary process exhibit dynamics that can be difficult to understand analytically. Here we show that a precise mathematical analogy can be drawn between certain evolutionary and thermodynamic systems, allowing application of the powerful machinery of statistical physics to analysis of a family of evolutionary models. Analytical results that follow directly from this approach include the steady-state distribution of fixed genotypes and th...

  14. Higher order chromatin structure: bridging physics and biology

    OpenAIRE

    Fudenberg, Geoffrey; Mirny, Leonid A.

    2012-01-01

    Recent advances in microscopy and genomic techniques have provided new insight into spatial chromatin organization inside of the nucleus. In particular, chromosome conformation capture data has highlighted the relevance of polymer physics for high-order chromatin organization. In this context, we review basic polymer states, discuss how an appropriate polymer model can be determined from experimental data, and examine the success and limitations of various polymer models of high-order interph...

  15. Dewetting and Hydrophobic Interaction in Physical and Biological Systems

    OpenAIRE

    Berne, Bruce J.; Weeks, John D.; Zhou, Ruhong

    2009-01-01

    Hydrophobicity manifests itself differently on large and small length scales. This review focuses on large length scale hydrophobicity, particularly on dewetting at single hydrophobic surfaces and drying in regions bounded on two or more sides by hydrophobic surfaces. We review applicable theories, simulations and experiments pertaining to large scale hydrophobicity in physical and biomoleclar systems and clarify some of the critical issues pertaining to this subject. Given space constraints,...

  16. Uncovering the underlying physical mechanisms of biological systems via quantification of landscape and flux

    Science.gov (United States)

    Li, Xu; Xiakun, Chu; Zhiqiang, Yan; Xiliang, Zheng; Kun, Zhang; Feng, Zhang; Han, Yan; Wei, Wu; Jin, Wang

    2016-01-01

    In this review, we explore the physical mechanisms of biological processes such as protein folding and recognition, ligand binding, and systems biology, including cell cycle, stem cell, cancer, evolution, ecology, and neural networks. Our approach is based on the landscape and flux theory for nonequilibrium dynamical systems. This theory provides a unifying principle and foundation for investigating the underlying mechanisms and physical quantification of biological systems. Project supported by the Natural Science Foundation of China (Grant Nos. 21190040, 11174105, 91225114, 91430217, and 11305176) and Jilin Province Youth Foundation, China (Grant No. 20150520082JH).

  17. Mathematical methods in physics distributions, Hilbert space operators, variational methods, and applications in quantum physics

    CERN Document Server

    Blanchard, Philippe

    2015-01-01

    The second edition of this textbook presents the basic mathematical knowledge and skills that are needed for courses on modern theoretical physics, such as those on quantum mechanics, classical and quantum field theory, and related areas.  The authors stress that learning mathematical physics is not a passive process and include numerous detailed proofs, examples, and over 200 exercises, as well as hints linking mathematical concepts and results to the relevant physical concepts and theories.  All of the material from the first edition has been updated, and five new chapters have been added on such topics as distributions, Hilbert space operators, and variational methods.   The text is divided into three main parts. Part I is a brief introduction to distribution theory, in which elements from the theories of ultradistributions and hyperfunctions are considered in addition to some deeper results for Schwartz distributions, thus providing a comprehensive introduction to the theory of generalized functions. P...

  18. A description of 60Co gamma irradiation facilities in the Radiation Biology and Health Physics branch

    International Nuclear Information System (INIS)

    The Radiation Biology and Health Physics Branch manages three 60Co irradiation facilities, to (Gammabeam 150C, Gammacell 200 and Gammacell 220) provide a range of dose rates suitable for variety of applications. This report describes the physical characteristics of the facilities, a description of the dosimetry and operating procedures. (author). 6 refs., tabs., figs

  19. Structure of physics and the chemical or biological action of ionizing radiations - rarely employed ideas

    International Nuclear Information System (INIS)

    The fact is pointed out that phenomena in radiochemistry and micro-scale radiobiology are non-linear similarly to phenomena in modern theoretical physics. A comparison is made of the conceptual development of theoretical physics and of theoretical radiation biology. The use of Bose-Einstein's exciton condensation is suggested for expressing the non-linearity of radiochemical and radiobiological processes. (Ha)

  20. Physical Activity: A Tool for Improving Health (Part 1--Biological Health Benefits)

    Science.gov (United States)

    Gallaway, Patrick J.; Hongu, Nobuko

    2015-01-01

    Extension educators have been promoting and incorporating physical activities into their community-based programs and improving the health of individuals, particularly those with limited resources. This article is the first of a three-part series describing the benefits of physical activity for human health: 1) biological health benefits of…

  1. Methodical Instructions For Solutions of Problems in Nuclear Physics

    OpenAIRE

    Troitskaya, Natalia I.

    2005-01-01

    This is a set of methodical instructions for solutions of problems in Nuclear Physics. It is written on the basis of seminars to the course of lectures on``Nuclear Physics'' delivered at the Physical and Mechanical Faculty of the St. Petersburg State Polytechnic University for the students of the 4th Course in ``Technical Physics'' and ``Medical Physics''. The main aim of these methodical instructions is to develop the experience of students in scientific approaches to solutions of practical ...

  2. Nonlocal reactive transport with physical, chemical, and biological heterogeneity

    Science.gov (United States)

    Hu, Bill X.; Cushman, John H.; Deng, Fei-Wen

    When a natural porous medium is viewed from an eulerian perspective, incomplete characterization of the hydraulic conductivity, chemical reactivity, and biological activity leads to nonlocal constitutive theories, irrespective of whether the medium has evolving heterogeneity with fluctuations over all scales. Within this framework a constitutive theory involving nonlocal dispersive and convective fluxes and nonlocal sources/sinks is developed for chemicals undergoing random linear nonequilibrium reactions and random equilibrium first-order decay in a random conductivity field. The resulting transport equations are solved exactly in Fourier-Laplace space and then numerically inverted to real space. Mean concentration contours and various spatial moments are presented graphically for several covariance structures. 1997 Published by Elsevier Science Ltd. All rights reserved

  3. River Pollution: Part II. Biological Methods for Assessing Water Quality.

    Science.gov (United States)

    Openshaw, Peter

    1984-01-01

    Discusses methods used in the biological assessment of river quality and such indicators of clean and polluted waters as the Trent Biotic Index, Chandler Score System, and species diversity indexes. Includes a summary of a river classification scheme based on quality criteria related to water use. (JN)

  4. Influence of physical and biological factors in cellular radiosensitivity

    International Nuclear Information System (INIS)

    The use of therapeutic radiopharmaceuticals is associated with radiation damage, and this at-nuclear physical properties of radionuclides used and the characteristics of the irradiated cells. The work deals with the damage caused by radiation to DNA, factors that condition and tools that can be used to measure it. It presents current concepts of death and cellular radiosensitivity, based on the pioneering work in this field. Enter the neighborhood effect and adaptive response and evaluates the influence of the same in the paradigms of classical radiobiology. (author)

  5. Physical and biological basis of hadron radiotherapy. Book of abstracts

    International Nuclear Information System (INIS)

    The Workshop was a satellite event of the 14th International Congress of Radiation Research (ICRR-2011). It was held in Cracow, Poland, on the 2 and 3 September 2011, at the Collegium Novum of the Jagiellonian University. The Workshop organized, jointly by the Institute of Nuclear Physics of the Polish Academy of Sciences and the Polish Radiation Research Society, would provide its participants with an opportunity to discuss current topics in proton and carbon radiotherapy, clinical aspects of ion radiotherapy, ion beam dosimetry, unwanted patient exposure, radiobiology for ion radiotherapy and other relevant subjects. Book of Abstracts contains abstracts of 33 oral presentations and 12 posters.

  6. Predicting economic growth with classical physics and human biology

    OpenAIRE

    Hans G. Danielmeyer; Thomas Martinetz

    2012-01-01

    We collect and analyze the data for working time, life expectancy, and the pair output and infrastructure of industrializing nations. During S-functional recovery from disaster the pair's time shifts yield 25 years for the infrastructure's physical lifetime. At G7 level the per capita outputs converge and the time shifts identify a heritable quantity with a reaction time of 62 years. It seems to control demand and the spare time required for enjoying G7 affluence. The sum of spare and working...

  7. Calibration of a coupled biological-physical model for prediction in a coastal inlet

    Science.gov (United States)

    Guarracino, M.; Dowd, M.; Sheng, J.; Cullen, J. J.

    2011-10-01

    We describe a numerical forecast system designed for prediction of physical and biological dynamics of a coastal inlet. It is based on a coastal ocean observatory that was located at Lunenburg Bay, Nova Scotia, Canada. Biological, chemical, optical, and physical measurements were collected from instrumented moorings, weekly sampling and detailed surveys from 2002 through 2007. Here we present a framework for calibration and evaluation of an ecosystem model using data from the summer of 2007. A three-dimensional hydrodynamic model was coupled to a simple biological (Nutrients-Phytoplankton-Detritus) model; a simple model was used so results could be compared directly to observed biological and chemical variables using skill scores as a first step toward data-assimilation modeling. As a complement to this analysis, variability of model output, e.g., the nutrient limitation term, was examined to understand the modeled biological response to the simulated physical environment. Skill scores based on variances in observed and simulated time-series of biological components were also investigated. Coastal upwelling/downwelling simulated through this model has been found to increase modeled biological activity in the bay. Also model skill in reproducing the observed patterns in nutrients and phytoplankton has been increased due to the restoring conditions for biology set up at the open ocean boundaries of the bay.

  8. Toward University Modeling Instruction—Biology: Adapting Curricular Frameworks from Physics to Biology

    OpenAIRE

    Manthey, Seth; Brewe, Eric

    2013-01-01

    University Modeling Instruction (UMI) is an approach to curriculum and pedagogy that focuses instruction on engaging students in building, validating, and deploying scientific models. Modeling Instruction has been successfully implemented in both high school and university physics courses. Studies within the physics education research (PER) community have identified UMI's positive impacts on learning gains, equity, attitudinal shifts, and self-efficacy. While the success of this pedagogical a...

  9. Computer diagnostics of level of professional competence formation of future physical culture teachers in the biological disciplines study

    Directory of Open Access Journals (Sweden)

    Voitovska O.N.

    2013-03-01

    Full Text Available The analysis of the level of professional competence formation of future physical culture teachers in the biological disciplines study was provided. The study involved 79 students. It is applied methods of teaching observation and experiment. The computer program of monitoring of professional competence of future teachers of physical education was described in the study of the biological sciences. Analyzed the results of 448 students questionnaire of the first and second year, studying at specialty "teacher of physical culture." Found that the results of the formative stages of the experiments show significant positive changes in the levels of formation of professional competence of students of the experimental group. Found that the increase in the number of students with high and medium level of formation of professional competence and reduced the number of students with low level of formation of professional competence.

  10. Development of methods for determining aflatoxins in biological material

    OpenAIRE

    Kussak, Anders

    1995-01-01

    In this thesis, it is shown how aflatoxins can be determined in biological material. The thesis is a summary of five papers. Aflatoxins are carcinogenic mycotoxins produced by Aspergillus moulds. Methods were developed for the determination of aflatoxins in samples of airborne dust and human urine collected at feed factories. For the dust samples from such agricultural products as copra, cotton seed and maize, methods were developed for the determination of aflatoxins B1, B2, G1 and G2. For u...

  11. What are the Effects of Implementing Learning-Focused Strategies in Biology and Physical Science Classrooms?

    Science.gov (United States)

    Simmons, Robin

    The objective of this study was to determine if Learning-Focused Strategies (LFS) implemented in high school science courses would affect student achievement and the pass rate of biology and physical science Common District Assessments (CDAs). The LFS, specific teaching strategies contained in the Learning-Focused Strategies Model (LFSM) Program were researched in this study. The LFSM Program provided a framework for comprehensive school improvement to those schools that implemented the program. The LFSM Program provided schools with consistent training in the utilization of exemplary practices and instruction. A high school located in the suburbs of Atlanta, Georgia was the focus of this investigation. Twelve high school science classrooms participated in the study: six biology and six physical science classes. Up-to-date research discovered that the strategies contained in the LFSM Program were research-based and highly effective for elementary and middle school instruction. Research on its effectiveness in high school instruction was the main focus of this study. This investigation utilized a mixed methods approach, in which data were examined qualitatively and quantitatively. Common District Assessment (CDA) quantitative data were collected and compared between those science classrooms that utilized LFS and those using traditional instructional strategies. Qualitative data were generated through classroom observations, student surveys, and teacher interviews. Individual data points were triangulated to determine trends of information reflecting the effects of implementing LFS. Based on the data collected in the research study, classrooms utilizing LFS were more successful academically than the classrooms using traditional instructional methods. Derived from the quantitative data, students in LFS classrooms were more proficient on both the biology and physical science Unit 1 CDAs, illustrating the effectiveness of LFS in the science classroom. Key terms

  12. Physics of Transport and Traffic Phenomena in Biology: from molecular motors and cells to organisms

    CERN Document Server

    Chowdhury, D; Nishinari, K; Chowdhury, Debashish; Schadschneider, Andreas; Nishinari, Katsuhiro

    2005-01-01

    Traffic-like collective movements are observed at almost all levels of biological systems. Molecular motor proteins like, for example, kinesin and dynein, which are the vehicles of almost all intra-cellular transport in eukayotic cells, sometimes encounter traffic jam that manifests as a disease of the organism. Similarly, traffic jam of collagenase MMP-1, which moves on the collagen fibrils of the extracellular matrix of vertebrates, has also been observed in recent experiments. Traffic-like movements of social insects like ants and termites on trails are, perhaps, more familiar in our everyday life. Experimental, theoretical and computational investigations in the last few years have led to a deeper understanding of the generic or common physical principles involved in these phenomena. In particular, some of the methods of non-equilibrium statistical mechanics, pioneered almost a hundred years ago by Einstein, Langevin and others, turned out to be powerful theoretical tools for quantitaive analysis of model...

  13. Evaluation of physical-chemical and biological treatment of shale oil retort water

    Energy Technology Data Exchange (ETDEWEB)

    Mercer, B.W.; Mason, M.J.; Spencer, R.R.; Wong, A.L.; Wakamiya, W.

    1982-09-01

    Bench scale studies were conducted to evaluate conventional physical-chemical and biological treatment processes for removal of pollutants from retort water produced by in situ shale oil recovery methods. Prior to undertaking these studies, very little information had been reported on treatment of retort water. A treatment process train patterned after that generally used throughout the petroleum refining industry was envisioned for application to retort water. The treatment train would consist of processes for removing suspended matter, ammonia, biodegradable organics, and nonbiodegradable or refractory organics. The treatment processes evaluated include anaerobic digestion and activated sludge for removal of biodegradable organics and other oxidizable substances; activated carbon adsorption for removal of nonbiodegradable organics; steam stripping for ammonia removal; and chemical coagulation, sedimentation and filtration for removal of suspended matter. Preliminary cost estimates are provided.

  14. Biological methods used to assess surface water quality

    Directory of Open Access Journals (Sweden)

    Szczerbiñska Natalia

    2015-12-01

    Full Text Available In accordance with the guidelines of the Water Framework Directive 2000/60 (WFD, both ecological and chemical statuses determine the assessment of surface waters. The profile of ecological status is based on the analysis of various biological components, and physicochemical and hydromorphological indicators complement this assessment. The aim of this article is to present the biological methods used in the assessment of water status with a special focus on bioassay, as well as to provide a review of methods of monitoring water status. Biological test methods include both biomonitoring and bioanalytics. Water biomonitoring is used to assess and forecast the status of water. These studies aim to collect data on water pollution and forecast its impact. Biomonitoring uses organisms which are characterized by particular vulnerability to contaminants. Bioindicator organisms are algae, fungi, bacteria, larval invertebrates, cyanobacteria, macroinvertebrates, and fish. Bioanalytics is based on the receptors of contaminants that can be biologically active substances. In bioanalytics, biosensors such as viruses, bacteria, antibodies, enzymes, and biotests are used to assess degrees of pollution.

  15. Analytical And Numerical Methods In Beam Physics

    CERN Document Server

    Andrianov, S

    2004-01-01

    This report is devoted to discussion of numerical and symbolic computing ratio beam physics. We tray to draw attention on basic conceptual and computational problems first of all. It is known that the main problem in modern computational beam physics connected with high performance computing realization. The most of used approaches are not appropriate for computing using multiprocessing systems. Here we give some possible solutions, which based on symbolic presentation of necessary information and modern information technologies.

  16. Diagnosis of Physical and Biological Controls on Phytoplankton Distribution in the Sargasso Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Caixia; Paola Malanotte-Rizzoli

    2014-01-01

    The linkage between physical and biological processes is studied by applying a one-dimensional physical-biological coupled model to the Sargasso Sea. The physical model is the Princeton Ocean Model and the biological model is a five-component system including phytoplankton, zooplankton, nitrate, ammonium, and detritus. The coupling between the physical and biological model is accomplished through vertical mixing which is parameterized by the level 2.5 Mellor and Yamada turbulence closure scheme. The coupled model investigates the annual cycle of ecosystem production and the response to external forcing, such as heat flux, wind stress, and surface salinity, and the relative importance of physical processes in affecting the ecosystem. Sensitivity ex-periments are also carried out, which provide information on how the model bio-chemical parameters affect the biological system. The computed seasonal cycles compare reasonably well with the observations of the Bermuda Atlantic Time-series Study (BATS). The spring bloom of phytoplankton occurs in March and April, right after the weakening of the winter mixing and before the estab-lishment of the summer stratification. The bloom of zooplankton occurs about two weeks after the bloom of phytoplankton. The sen-sitivity experiments show that zooplankton is more sensitive to the variations of biochemical parameters than phytoplankton.

  17. Degradation of Some Textile Dyes using Biological and Physical Treatments

    International Nuclear Information System (INIS)

    A total of twenty samples composed of ten samples of decaying eucalyptus leaves and ten soil samples were collected from El-Kanater El-Khairia district. All isolates were purified and identified to the species level. They found to be belonging to two main genera: Aspergillus sp. and Penicillium sp. The obtained fungal isolates were screened for testing their ability to decolorize Isolan dyes. The strain Aspergillus niger ES-5 was chosen for its highest ability to decolorize the four Isolan dyes. The biological decolorization of the textile metal azo dye was investigated under co-metabolic conditions. The decolorization capacity of the strain was influenced by the presence and/or absence of media components. The majority of decolorization was growth related, where resulted in 90.4%, 99.6%, 95.0% and 94.6% for I.Y, I.R, I.N and I.G, respectively after 72 h, only 2.5, 1.3, 1.4 and 3.0% for I.Y, I.R, I.N and I.G, respectively were desorbed, while negligible decolorization was detected using extracellular fluid (ECF) as well as using dead pellets. The addition of the dye to fungal cultures didn’t affect the extracellular GOD production while intracellular GOD production exhibited a different profile. Pictures of the mycelia represent dye uptake over the 72 h period of decolorization. The metal detection using Energy Dispersive X-ray Spectroscopy (EDS) of the outer fungal mycelium wall and ECF were both below detection level after the decolorization process took place. Thus, decolorization process and the removal of the elements by A. niger ES-5 involve initial adsorption followed by entrapment of the adsorbed dye inside the fungal biomass. Gamma rays increase color intensity in I.Y, while the other three Isolan dyes showed negative decolorization efficiency till 2.5 kGy after which, slow increase in the decolorization was observed.

  18. Acceleration of Peripheral Nerve Regeneration through Asymmetrically Porous Nerve Guide Conduit Applied with Biological/Physical Stimulation

    OpenAIRE

    Kim, Jin Rae; Oh, Se Heang; Kwon, Gu Birm; Namgung, Uk; Song, Kyu Sang; Jeon, Byeong Hwa; Lee, Jin Ho

    2013-01-01

    Sufficient functional restoration of damaged peripheral nerves is a big clinical challenge. In this study, a nerve guide conduit (NGC) with selective permeability was prepared by rolling an asymmetrically porous polycaprolactone/Pluronic F127 membrane fabricated using a novel immersion precipitation method. Dual stimulation (nerve growth factor [NGF] as a biological stimulus and low-intensity pulse ultrasound [US] as a physical stimulus) was adapted to enhance nerve regeneration through an NG...

  19. Teaching physics to life science students - Examining the role of biological context

    Science.gov (United States)

    Crouch, Catherine H.; Heller, Kenneth

    2012-02-01

    We describe a research agenda to inform renovating the introductory physics course commonly taught to life science majors. The theoretical framework of the renovation is the cognitive apprenticeship model, in which learning occurs most effectively in an environment of expert practices so that students can articulate why their learning matters. This model is supported by studies of transfer that suggest for students to successfully apply physics to another field, they need practice making such applications. Guided by this theoretical framework, we have begun to restructure our introductory physics courses for these students around biologically rich contexts - examples in which fundamental physics plays a significant role in understanding a biological system - to make explicit the value of physics to the life sciences. This requires restructuring the course content to reflect the topics most relevant to biology. In this paper we describe our approach to this course, identify research directions addressing (1) the role of biological context in learning for these students and (2) issues in implementing such a course for physics faculty, and summarize preliminary results.

  20. Using the case-study method in teaching college physics

    OpenAIRE

    Burko, Lior M.

    2016-01-01

    The case-study teaching method has a long history (starting at least with Socrates), and wide current use in business schools, medical schools, law schools, and a variety of other disciplines. However, relatively little use is made of it in the physical sciences, specifically in physics or astronomy. The case-study method should be considered by physics faculty as part of the effort to transition the teaching of college physics from the traditional frontal-lecture format to other formats that...

  1. Project as an education method in teaching of physics

    OpenAIRE

    VEVERKOVÁ, Klára

    2011-01-01

    The diploma thesis ?Project as an educational method for teaching physics ?deals with the possibilities of using project-based method for teaching physics at primary schools. Not only does it contain the theoretical background of project-based teaching, but also deals with practical issues in the form of an implementation of a chosen project ?Physics and physical education?. The aim of said project was to evaluate the efficiency of project-based teaching as far as the knowledge of pupils and ...

  2. Atmospheric Physics Background – Methods – Trends

    CERN Document Server

    2012-01-01

    On the occasion of the 50th anniversary of the Institute of Atmospheric Physics of the German Aerospace Center (DLR), this book presents more than 50 chapters highlighting results of the institute’s research. The book provides an up-to-date, in-depth survey across the entire field of atmospheric science, including atmospheric dynamics, radiation, cloud physics, chemistry, climate, numerical simulation, remote sensing, instruments and measurements, as well as atmospheric acoustics. The authors have provided a readily comprehensible and self-contained presentation of the complex field of atmospheric science. The topics are of direct relevance for aerospace science and technology. Future research challenges are identified.

  3. Student Active Learning Methods in Physical Chemistry

    Science.gov (United States)

    Hinde, Robert J.; Kovac, Jeffrey

    2001-01-01

    We describe two strategies for implementing active learning in physical chemistry. One involves supplementing a traditional lecture course with heavily computer-based active-learning exercises carried out by cooperative groups in a department computer lab. The other uses cooperative learning almost exclusively, supplemented by occasional mini-lectures. Both approaches seemed to result in better student learning and a more positive attitude toward the subject. On the basis of our respective experiences using active learning techniques, we discuss some of the strengths of these techniques and some of the challenges we encountered using the active-learning approach in teaching physical chemistry.

  4. [Streptokinase: correlation between different methods of biological evaluation].

    Science.gov (United States)

    Oliva, L M; Guagliardo, M V; Albertengo, M E

    1998-06-01

    A study was carried out to establish an appropriate method for streptokinase (SK) potency determination (biological assay) in order to fulfil the main function of the Instituto Nacional de Medicamentos respecting products marketed in Argentina. The potency of different commercial samples of SK was determined against the International Standard, and three internationally accepted methods were used for this purpose: fibrin plate, clot lysis and chromogenic method. The analysis of results suggests that the fibrin plate method is the least precise and reproducible. The clot lysis and chromogenic methods demonstrated great precision and reproducibility, giving a correlation coefficient of 0.99. It is concluded that both of these methods are best suited to determine potency of SK commercial products. PMID:9741232

  5. Biology and physics competencies for pre-health and other life sciences students.

    Science.gov (United States)

    Hilborn, Robert C; Friedlander, Michael J

    2013-06-01

    The recent report on the Scientific Foundations for Future Physicians (SFFP) and the revised Medical College Admissions Test (MCAT) reframe the preparation for medical school (and other health professional schools) in terms of competencies: what students should know and be able to do with that knowledge, with a strong emphasis on scientific inquiry and research skills. In this article, we will describe the thinking that went into the SFFP report and what it says about scientific and quantitative reasoning, focusing on biology and physics and the overlap between those fields. We then discuss how the SFFP report set the stage for the discussion of the recommendations for the revised MCAT, which will be implemented in 2015, again focusing the discussion on biology and physics. Based on that framework, we discuss the implications for undergraduate biology and physics education if students are to be prepared to demonstrate these competencies. PMID:23737625

  6. Carriers and sideband pairs and their analogues in physics and Biology

    Science.gov (United States)

    Goldman, Stanford

    1982-09-01

    This is a further development of the author's paper “A Unified Theory of Biology and Physics.” It is found that male and female in biology, as well as particle and antiparticle in physics, are analogues of symmetrical sideband pairs in communication theory. This gives a new point of view from which to investigate the significance and characteristics of these different paired entities. These findings are intimately related to the fact that there are two transform domains of representation of entities in all the cases involved. They are the somatic and the genetic domains in biology, the configuration domain and the domain of conserved observables in physics, and the time and frequency domains in communication.

  7. Computational and Biological Analogies for Understanding Fine-Tuned Parameters in Physics

    CERN Document Server

    Vidal, Clement

    2010-01-01

    In this philosophical paper, we explore computational and biological analogies to address the fine-tuning problem in cosmology. We first clarify what it means for physical constants or initial conditions to be fine-tuned. We review important distinctions such as the dimensionless and dimensional physical constants, and the classification of constants proposed by Levy-Leblond. Then we explore how two great analogies, computational and biological, can give new insights into our problem. This paper includes a preliminary study to examine the two analogies. Importantly, analogies are both useful and fundamental cognitive tools, but can also be misused or misinterpreted. The idea that our universe might be modelled as a computational entity is analysed, and we discuss the distinction between physical laws and initial conditions using algorithmic information theory. Smolin introduced the theory of "Cosmological Natural Selection" with a biological analogy in mind. We examine an extension of this analogy involving i...

  8. Combining various biological methods to control powdery mildew of tomato

    OpenAIRE

    Bardin, Marc; Dantony, Lea; Duffaud, Magali; Neu, Laurent; Pascal, Michel; Troulet, Claire; Nicot, Philippe

    2014-01-01

    Various biological methods, mainly based on the utilization of antagonistic microorganisms or plant extracts, have been studied to control powdery mildews. The hyperparasite fungus Ampelomyces quisqualis (AQ-10, De Sangosse) is registered in many countries to control powdery mildew on various crops, including Oidium neolycopersici on tomato in France. A plant extract from orange (Prev-Am, Vivagro) is registered to control powdery mildew and whitefly on various crops but its effect on tomat...

  9. Biclustering Methods: Biological Relevance and Application in Gene Expression Analysis

    OpenAIRE

    Ali Oghabian; Sami Kilpinen; Sampsa Hautaniemi; Elena Czeizler

    2014-01-01

    DNA microarray technologies are used extensively to profile the expression levels of thousands of genes under various conditions, yielding extremely large data-matrices. Thus, analyzing this information and extracting biologically relevant knowledge becomes a considerable challenge. A classical approach for tackling this challenge is to use clustering (also known as one-way clustering) methods where genes (or respectively samples) are grouped together based on the similarity of their expressi...

  10. ACTIVE AND PARTICIPATORY METHODS IN BIOLOGY: PROBLEM-SOLVING

    Directory of Open Access Journals (Sweden)

    Adela NEMEŞ

    2010-01-01

    Full Text Available We face with considerable challenge of developing students’ problem solving skills in our difficult environment. Good problem solving skills empower managers in their professional and personal lives. Problem solving skills are valued by academics and employers. The informations in Biology are often presented in abstract forms without contextualisation. Creative problem-solving process involves a few steps, which together provide a structured procedure for identifying challenges, generating ideas and implementing innovative solutions: identifying the problem, searching for possible solutions, selecting the most optimal solution and implementing a possible solution. Each aspect of personality has a different orientation to problem solving, different criteria for judging the effectiveness of the process and different associated strengths. Using real-world data in sample problems will also help facilitate the transfer process, since students can more easily identify with the context of a given situation. The paper describes the use of the Problem-Solving in Biology and the method of its administration. It also presents the results of a study undertaken to evaluate the value in teaching Biology. Problem-solving is seen as an essential skill that is developed in biology education.

  11. Physical, chemical and biological characterization of the sanitary landfill leachate in Limeira-SP city.

    Directory of Open Access Journals (Sweden)

    Ronaldo Teixeira Pelegrini

    2007-07-01

    Full Text Available This work presents an evaluation of the physical, chemical and biological characteristics of the waste leachate originated from solids waste mass and after permanence in average of 24 hours in the captation pond, which is located on the sanitary landfill in Limeira-SP. The points were denominated Point 0: entrance of leachate in natura in the pond and Point 1: exit of leachate from the pond. The study was accomplished through of the monitoring of physical (pH, color, turbidity, conductivity and temperature, chemical (alkalinity, acidity, phosphorus, amoniacal nitrogen, nitrite, nitrate and TOC and biological (heterotrophic bacterial parameters during a period of 50 days.

  12. Biological and physical oceanographic sensitivity analyses for subseabed disposal of high-level waste

    International Nuclear Information System (INIS)

    This report presents an investigation and sensitivity analysis of two segments of the MARINRAD system model - the physical oceanographic and biological transport of radionuclides. MARINRAD is a systems model developed by The Analytic Sciences Corporation to assess the consequences of releasing radioactive wastes into the ocean. The section on physical oceanography covers release rates, partition coefficients (sorption within the water column), and ocean transport parameters. The biological transport section investigates the relative importance of various pathways, concentration factors, and the contribution to the overall dose from the bioaccumulation of radionuclides in a deep-water aquatic food chain

  13. 4D-Var data assimilation system for a coupled physical biological model

    Indian Academy of Sciences (India)

    J M Lellouche; M Ouberdous; W Eifler

    2000-12-01

    A 3-compartment model of phytoplankton growth dynamics has been coupled with a primitive-equation circulation model to better understand and quantify physical and biological processes in the Adriatic Sea. This paper presents the development and application of a data assimilation procedure based on optimal control theory. The aim of the procedure is to identify a set of model coefficient values that ensures the best fit between data and model results by minimizing a function that measures model and data discrepancies. In this sense, twin experiments have been successfully implemented in order to have a better estimation of biological model parameters and biological initial conditions.

  14. A poroelastic immersed boundary method with applications to cell biology

    Science.gov (United States)

    Strychalski, Wanda; Copos, Calina A.; Lewis, Owen L.; Guy, Robert D.

    2015-02-01

    The immersed boundary method is a widely used mixed Eulerian/Lagrangian framework for simulating the motion of elastic structures immersed in viscous fluids. In the traditional immersed boundary method, the fluid and structure move with the same velocity field. In this work, a model based on the immersed boundary method is presented for simulating poroelastic media in which the fluid permeates a porous, elastic structure of small volume fraction that moves with its own velocity field. Two distinct methods for calculating elastic stresses are presented and compared. The methods are validated on a radially symmetric test problem by comparing with a finite difference solution of the classical equations of poroelasticity. Finally, two applications of the modeling framework to cell biology are provided: cellular blebbing and cell crawling. It is shown that in both examples, poroelastic effects are necessary to explain the relevant mechanics.

  15. Local Physical Coordinates from Symplectic Projector Method

    Science.gov (United States)

    de Andrade, M. A.; Santos, M. A.; Vancea, I. V.

    The basic arguments underlying the symplectic projector method are presented. By this method, local free coordinates on the constraint surface can be obtained for a broader class of constrained systems. Some interesting examples are analyzed.

  16. Local Physical Coodinates from Symplectic Projector Method

    CERN Document Server

    De Andrade, M A; Vancea, I V

    2001-01-01

    The basic arguments underlying the symplectic projector method are presented. By this method, local free coordinates on the constrait surface can be obtained for a broader class of constrained systems. Some interesting examples are analyzed.

  17. Least squares methods in physics and engineering

    International Nuclear Information System (INIS)

    These lectures deal with numerical methods representing the state of the art, including the available computer software. First a brief background of basic matrix factorizations is given. Dense linear problems are then treated, including methods for updating the solution when rows and variables are added or deleted. Special consideration is given to weighted least squares problems and constrained problems. Regularization of ill-posed problems are briefly surveyed. Sparse linear least squares problems are treated in some detail. Different ordering schemes, including ordering to block-angular form and nested dissection, and iterative methods are discussed. Finally a survey of methods for nonlinear least squares problems is given. The Gauss-Newton method is analyzed and its local convergence derived. Levenberg-Marquardt methods are discussed and different methods using second derivative information surveyed. Special methods are given for separable linear-nonlinear problems. (orig.)

  18. Method and apparatus to image biological interactions in plants

    Science.gov (United States)

    Weisenberger, Andrew; Bonito, Gregory M.; Reid, Chantal D.; Smith, Mark Frederick

    2015-12-22

    A method to dynamically image the actual translocation of molecular compounds of interest in a plant root, root system, and rhizosphere without disturbing the root or the soil. The technique makes use of radioactive isotopes as tracers to label molecules of interest and to image their distribution in the plant and/or soil. The method allows for the study and imaging of various biological and biochemical interactions in the rhizosphere of a plant, including, but not limited to, mycorrhizal associations in such regions.

  19. Nuclear physics methods in materials research

    International Nuclear Information System (INIS)

    The brochure contains the abstracts of the papers presented at the 7th EPS meeting 1980 in Darmstadt. The main subjects were: a) Neutron scattering and Moessbauer effect in materials research, b) ion implantation in micrometallurgy, c) applications of nuclear reactions and radioisotopes in research on solids, d) recent developments in activation analysis and e) pions, positrons, and heavy ions applied in solid state physics. (RW)

  20. From Molecules to Living Organisms : an Interplay between Biology and Physics : Lecture Notes of the Les Houches School of Physics

    CERN Document Server

    Nury, Hughes; Parcy, François; Ruigrok, Rob W H; Ziegler, Christine; Cugliandolo, Leticia F; Session CII

    2016-01-01

    The aim of this book is to provide new ideas for studying living matter by a simultaneous understanding of behavior from molecules to the cell, to the whole organism in the light of physical concepts. Indeed, forces guide most biological phenomena. In some cases these forces can be well-described and thus used to model a particular biological phenomenon. This is exemplified here by the study of membranes, where their shapes and curvatures can be modeled using a limited number of parameters that are measured experimentally. The growth of plants is another example where the combination of physics, biology and mathematics leads to a predictive model. The laws of thermodynamics are essential, as they dictate the behavior of proteins, or more generally biological molecules, in an aqueous environment. Integrated studies from the molecule to a larger scale need a combination of cutting-edge approaches, such as the use of new X-ray sources, in-cell NMR, cryo-electron microscopy or single-molecule microscopy. Some are...

  1. Methods of 15N tracer research in biological systems

    International Nuclear Information System (INIS)

    The application of the stable isotope 15N is of increasing importance in different scientific disciplines, especially in medicine, agriculture, and the biosciences. The close correlation between the growing interest and improvements of analytical procedures resulted in remarkable advances in the 15N tracer technique. On the basis of the latest results of 15N tracer research in life sciences and agriculture methods of 15N tracer research in biological systems are compiled. The 15N methodology is considered under three headings: Chemical analysis with a description of methods of sample preparation (including different separation and isolation methods for N-containing substances of biological and agricultural origin) and special procedures converting ammonia to molecular nitrogen. Isotopic analysis with a review on the most important methods of isotopic analysis of nitrogen: mass spectrometry (including the GC-MS technique), emission spectrometry, NMR spectroscopy, and other analytical procedures. 15N-tracer techniques with a consideration of the role of the isotope dilution analysis as well as different labelling techniques and the mathematical interpretation of tracer data (modelling, N turnover experiments). In these chapters also sources of errors in chemical and isotopic analysis, the accuracy of the different methods and its importance on tracer experiments are discussed. Procedures for micro scale 15N analysis and aspects of 15N analysis on the level of natural abundance are considered. Furthermore some remarks on isotope effects in 15N tracer experiments are made. (author)

  2. How can we improve problem-solving in undergraduate biology? Applying lessons from 30 years of physics education research

    CERN Document Server

    Hoskinson, Anne-Marie; Knight, Jennifer K

    2012-01-01

    Modern biological problems are complex. If students are to successfully grapple with such problems as scientists and citizens, they need to have practiced solving authentic, complex problems during their undergraduate years. Physics education researchers have investigated student problem-solving for the last three decades. Although the surface features and content of biology problems differ from physics problems, teachers of both sciences want students to learn to explain patterns and processes in the natural world and to make predictions about system behaviors. After surveying literature on problem-solving in physics and biology, we propose how biology education researchers could apply research-supported pedagogical techniques from physics to enhance biology students' problem-solving. First, we characterize the problems that biology students are typically asked to solve. We then describe the development of research-validated physics problem-solving curricula. Finally, we propose how biology scholars can appl...

  3. Exergames: neuroplastic hypothesis about cognitive improvement and biological effects on physical function of institutionalized older persons

    OpenAIRE

    Renato Sobral Monteiro; César Augusto Otero Vaghetti; Osvaldo José M. Nascimento; Jerson Laks; Andrea Camaz Deslandes

    2016-01-01

    Exergames can be considered a dual task because the games are performed by a man-videogame interface, requiring cognitive and motor functions simultaneously. Although the literature has shown improvements of cognitive and physical functions due to exergames, the intrinsic mechanisms involved in these functional changes have still not been elucidated. The aims of the present study were (1) to demonstrate the known biological mechanisms of physical exercise regarding muscle adaptation and estab...

  4. National Aeronautics and Space Administration Biological and Physical Research Enterprise Strategy

    Science.gov (United States)

    2003-01-01

    As the 21st century begins, NASA's new Vision and Mission focuses the Agency's Enterprises toward exploration and discovery.The Biological and Physical Research Enterprise has a unique and enabling role in support of the Agency's Vision and Mission. Our strategic research seeks innovations and solutions to enable the extension of life into deep space safely and productively. Our fundamental research, as well as our research partnerships with industry and other agencies, allow new knowledge and tech- nologies to bring improvements to life on Earth. Our interdisciplinary research in the unique laboratory of microgravity addresses opportunities and challenges on our home planet as well as in space environments. The Enterprise maintains a key role in encouraging and engaging the next generation of explorers from primary school through the grad- uate level via our direct student participation in space research.The Biological and Physical Research Enterprise encompasses three themes. The biological sciences research theme investigates ways to support a safe human presence in space. This theme addresses the definition and control of physiological and psychological risks from the space environment, including radiation,reduced gravity, and isolation. The biological sciences research theme is also responsible for the develop- ment of human support systems technology as well as fundamental biological research spanning topics from genomics to ecologies. The physical sciences research theme supports research that takes advantage of the space environment to expand our understanding of the fundamental laws of nature. This theme also supports applied physical sciences research to improve safety and performance of humans in space. The research partnerships and flight support theme establishes policies and allocates space resources to encourage and develop entrepreneurial partners access to space research.Working together across research disciplines, the Biological and Physical

  5. Methods of the physics of porous media

    CERN Document Server

    Wong, Po-Zen; De Graef, Marc

    1999-01-01

    Over the past 25 years, the field of VUV physics has undergone significant developments as new powerful spectroscopic tools, VUV lasers, and optical components have become available. This volume is aimed at experimentalists who are in need of choosing the best type of modern instrumentation in this applied field. In particular, it contains a detailed chapter on laboratory sources. This volume provides an up-to-date description of state-of-the-art equipment and techniques, and a broad reference bibliography. It treats phenomena from the standpoint of an experimental physicist, whereby such topi

  6. Mathematical methods in physics and engineering

    CERN Document Server

    Dettman, John W

    2011-01-01

    Intended for college-level physics, engineering, or mathematics students, this volume offers an algebraically based approach to various topics in applied math. It is accessible to undergraduates with a good course in calculus which includes infinite series and uniform convergence. Exercises follow each chapter to test the student's grasp of the material; however, the author has also included exercises that extend the results to new situations and lay the groundwork for new concepts to be introduced later. A list of references for further reading will be found at the end of each chapter. For t

  7. Advanced Software Methods for Physics Analysis

    International Nuclear Information System (INIS)

    Unprecedented data analysis complexity is experienced in modern High Energy Physics experiments. The complexity arises from the growing size of recorded data samples, the large number of data analyses performed by different users in each single experiment, and the level of complexity of each single analysis. For this reason, the requirements on software for data analysis impose a very high level of reliability. We present two concrete examples: the former from BaBar experience with the migration to a new Analysis Model with the definition of a new model for the Event Data Store, the latter about a toolkit for multivariate statistical and parametric Monte Carlo analysis developed using generic programming

  8. Biclustering methods: biological relevance and application in gene expression analysis.

    Science.gov (United States)

    Oghabian, Ali; Kilpinen, Sami; Hautaniemi, Sampsa; Czeizler, Elena

    2014-01-01

    DNA microarray technologies are used extensively to profile the expression levels of thousands of genes under various conditions, yielding extremely large data-matrices. Thus, analyzing this information and extracting biologically relevant knowledge becomes a considerable challenge. A classical approach for tackling this challenge is to use clustering (also known as one-way clustering) methods where genes (or respectively samples) are grouped together based on the similarity of their expression profiles across the set of all samples (or respectively genes). An alternative approach is to develop biclustering methods to identify local patterns in the data. These methods extract subgroups of genes that are co-expressed across only a subset of samples and may feature important biological or medical implications. In this study we evaluate 13 biclustering and 2 clustering (k-means and hierarchical) methods. We use several approaches to compare their performance on two real gene expression data sets. For this purpose we apply four evaluation measures in our analysis: (1) we examine how well the considered (bi)clustering methods differentiate various sample types; (2) we evaluate how well the groups of genes discovered by the (bi)clustering methods are annotated with similar Gene Ontology categories; (3) we evaluate the capability of the methods to differentiate genes that are known to be specific to the particular sample types we study and (4) we compare the running time of the algorithms. In the end, we conclude that as long as the samples are well defined and annotated, the contamination of the samples is limited, and the samples are well replicated, biclustering methods such as Plaid and SAMBA are useful for discovering relevant subsets of genes and samples. PMID:24651574

  9. Biclustering methods: biological relevance and application in gene expression analysis.

    Directory of Open Access Journals (Sweden)

    Ali Oghabian

    Full Text Available DNA microarray technologies are used extensively to profile the expression levels of thousands of genes under various conditions, yielding extremely large data-matrices. Thus, analyzing this information and extracting biologically relevant knowledge becomes a considerable challenge. A classical approach for tackling this challenge is to use clustering (also known as one-way clustering methods where genes (or respectively samples are grouped together based on the similarity of their expression profiles across the set of all samples (or respectively genes. An alternative approach is to develop biclustering methods to identify local patterns in the data. These methods extract subgroups of genes that are co-expressed across only a subset of samples and may feature important biological or medical implications. In this study we evaluate 13 biclustering and 2 clustering (k-means and hierarchical methods. We use several approaches to compare their performance on two real gene expression data sets. For this purpose we apply four evaluation measures in our analysis: (1 we examine how well the considered (biclustering methods differentiate various sample types; (2 we evaluate how well the groups of genes discovered by the (biclustering methods are annotated with similar Gene Ontology categories; (3 we evaluate the capability of the methods to differentiate genes that are known to be specific to the particular sample types we study and (4 we compare the running time of the algorithms. In the end, we conclude that as long as the samples are well defined and annotated, the contamination of the samples is limited, and the samples are well replicated, biclustering methods such as Plaid and SAMBA are useful for discovering relevant subsets of genes and samples.

  10. Using Metaphor Theory to Examine Conceptions of Energy in Biology, Chemistry, and Physics

    Science.gov (United States)

    Lancor, Rachael

    2014-01-01

    Energy is one of the most important unifying themes in science. Yet the way energy is conceptualized varies depending on context. In this paper, the discourse used to explain the role of energy in systems from biology, chemistry, and physics is examined from the perspective of metaphor theory. Six substance metaphors for energy are identified in…

  11. Physical and biological changes of suspended particles in a free surface flow constructed wetland

    NARCIS (Netherlands)

    B.T.M. Mulling; R.M. van den Boomen; T.H.L. Claassen; H.G. van der Geest; J.W.N.M. Kappelhof; W. Admiraal

    2013-01-01

    Suspended particles are considered as contaminants in treated wastewater and can have profound effects on the biological, physical and chemical properties of receiving aquatic ecosystems, depending on the concentration, type and nature of the suspended particles. Constructed wetlands are known to su

  12. Diagnostic opto-electronic system for measuring physical and biological characteristics of the skin in vivo

    Science.gov (United States)

    Makara, Ivanna V.; Kozhukhar, Oleksander T.; Komada, Pawel; Dussembayeva, Shynar

    2015-12-01

    Actuality development of optoelectronic rapid diagnostic system for measuring physical and biological characteristics of the skin in vivo with radiation of electromagnetic radiation in the optical range to obtain objective information on the spatial distribution of biochemical and morphological and anatomical components are different for state standards and pathology.

  13. Resource Letter TTSM-1: Teaching thermodynamics and statistical mechanics in introductory physics, chemistry, and biology

    OpenAIRE

    Dreyfus, Benjamin W.; Geller, Benjamin D.; Meltzer, David E.; Sawtelle, Vashti

    2014-01-01

    This Resource Letter draws on discipline-based education research from physics, chemistry, and biology to collect literature on the teaching of thermodynamics and statistical mechanics in the three disciplines. While the overlap among the disciplinary literatures is limited at present, we hope this Resource Letter will spark more interdisciplinary interaction.

  14. The Reproduction of Biological "Race" through Physical Education Textbooks and Curriculum

    Science.gov (United States)

    McDonald, Brent

    2013-01-01

    This paper examines the usage of "race" in high school physical education textbooks in Australia. In particular, it examines the concept of biological "race" in connection with human performance in sport. DNA studies do not indicate that separate classifiable subspecies (races) exist within modern humans. A content analysis of…

  15. Job Satisfaction Levels of Secondary School Physics, Chemistry and Biology Teachers

    Science.gov (United States)

    Maskan, A. Kadir

    2014-01-01

    The purpose of this study is to determine the job satisfaction levels of the teachers participating in the study and to investigate whether their job satisfaction levels differ with respect to certain variables. The participants of the study were 297 science teachers (physics: 104, chemistry: 105, biology: 87 and 1 N/A) from secondary schools in…

  16. Essential Concepts and Underlying Theories from Physics, Chemistry, and Mathematics for "Biochemistry and Molecular Biology" Majors

    Science.gov (United States)

    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,…

  17. Leveraging a Relationship with Biology to Expand a Relationship with Physics

    Science.gov (United States)

    Sawtelle, Vashti; Turpen, Chandra

    2016-01-01

    This work examines how experiences in one disciplinary domain (biology) can impact the relationship a student builds with another domain (physics). We present a model for disciplinary relationships using the constructs of identity, affect, and epistemology. With these constructs we examine an ethnographic case study of a student who experienced a…

  18. Linking Automated Data Analysis and Visualization with Applications in Developmental Biology and High-Energy Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ruebel, Oliver [Technical Univ. of Darmstadt (Germany)

    2009-11-20

    Knowledge discovery from large and complex collections of today's scientific datasets is a challenging task. With the ability to measure and simulate more processes at increasingly finer spatial and temporal scales, the increasing number of data dimensions and data objects is presenting tremendous challenges for data analysis and effective data exploration methods and tools. Researchers are overwhelmed with data and standard tools are often insufficient to enable effective data analysis and knowledge discovery. The main objective of this thesis is to provide important new capabilities to accelerate scientific knowledge discovery form large, complex, and multivariate scientific data. The research covered in this thesis addresses these scientific challenges using a combination of scientific visualization, information visualization, automated data analysis, and other enabling technologies, such as efficient data management. The effectiveness of the proposed analysis methods is demonstrated via applications in two distinct scientific research fields, namely developmental biology and high-energy physics.Advances in microscopy, image analysis, and embryo registration enable for the first time measurement of gene expression at cellular resolution for entire organisms. Analysis of high-dimensional spatial gene expression datasets is a challenging task. By integrating data clustering and visualization, analysis of complex, time-varying, spatial gene expression patterns and their formation becomes possible. The analysis framework MATLAB and the visualization have been integrated, making advanced analysis tools accessible to biologist and enabling bioinformatic researchers to directly integrate their analysis with the visualization. Laser wakefield particle accelerators (LWFAs) promise to be a new compact source of high-energy particles and radiation, with wide applications ranging from medicine to physics. To gain insight into the complex physical processes of particle

  19. Linking Automated Data Analysis and Visualization with Applications in Developmental Biology and High-Energy Physics

    International Nuclear Information System (INIS)

    Knowledge discovery from large and complex collections of today's scientific datasets is a challenging task. With the ability to measure and simulate more processes at increasingly finer spatial and temporal scales, the increasing number of data dimensions and data objects is presenting tremendous challenges for data analysis and effective data exploration methods and tools. Researchers are overwhelmed with data and standard tools are often insufficient to enable effective data analysis and knowledge discovery. The main objective of this thesis is to provide important new capabilities to accelerate scientific knowledge discovery form large, complex, and multivariate scientific data. The research covered in this thesis addresses these scientific challenges using a combination of scientific visualization, information visualization, automated data analysis, and other enabling technologies, such as efficient data management. The effectiveness of the proposed analysis methods is demonstrated via applications in two distinct scientific research fields, namely developmental biology and high-energy physics.Advances in microscopy, image analysis, and embryo registration enable for the first time measurement of gene expression at cellular resolution for entire organisms. Analysis of high-dimensional spatial gene expression datasets is a challenging task. By integrating data clustering and visualization, analysis of complex, time-varying, spatial gene expression patterns and their formation becomes possible. The analysis framework MATLAB and the visualization have been integrated, making advanced analysis tools accessible to biologist and enabling bioinformatic researchers to directly integrate their analysis with the visualization. Laser wakefield particle accelerators (LWFAs) promise to be a new compact source of high-energy particles and radiation, with wide applications ranging from medicine to physics. To gain insight into the complex physical processes of particle

  20. Essential Mathematical Methods for the Physical Sciences

    Science.gov (United States)

    Riley, K. F.; Hobson, M. P.

    2011-02-01

    1. Matrices and vector spaces; 2. Vector calculus; 3. Line, surface and volume integrals; 4. Fourier series; 5. Integral transforms; 6. Higher-order ODEs; 7. Series solutions of ODEs; 8. Eigenfunction methods; 9. Special functions; 10. Partial differential equations; 11. Solution methods for PDEs; 12. Calculus of variations; 13. Integral equations; 14. Complex variables; 15. Applications of complex variables; 16. Probability; 17. Statistics; Appendices; Index.

  1. PHYSICAL METHODS IN AGRO-FOOD CHAIN

    OpenAIRE

    ANNA ALADJADJIYAN; KAKANAKOVA, Andriana

    2009-01-01

    Chemical additives (fertilizers and plant protection preparations) are largely used for improving the production yield of food produce. Their application often causes the contamination of raw materials for food production, which can be dangerous for the health of consumers. Alternative methods are developed and implemented to improve and ensure the safety of on-farm production. The substitution of chemical fertilizers and soil additives with alternative treatment methods, such as irradiation,...

  2. Comparing results of cultured and uncultured biological methods used in biological phosphorus removal

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Increasing attention has been paid to phosphate-accumulating organisms (PAOs) for their important role in biological phosphorus removal. In this study, microbial communities of PAOs cultivated under different carbon sources (sewage, glucose, and sodium acetate) were investigated and compared through culture-dependent and culture-independent methods, respectively. The results obtained using denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction-amplified 16S rDNA fragments revealed that the diversity of bacteria in a sewage-fed reactor (1#) was much higher than in a glucose-fed one (2#) and a sodium acetate-fed one (3#); there were common PAOs in three reactors fed by different carbon sources. Five strains were separated from three systems by using a phosphate-rich medium; they were from common bacteria isolated and three isolates could not be found in DGGE profile at all. Two isolates had good phosphorus removal ability. When the microbial diversity was studied, the molecular biological method was better than the culture-dependent one. When phosphorus removal characteristics were investigated, culture-dependent approach was more effective. Thus a combination of two methods is necessary to have a comprehensive view of PAOs.

  3. Theoretical and methodical knowledge of students of discipline "Physical education"

    Directory of Open Access Journals (Sweden)

    Berezka S.M.

    2011-03-01

    Full Text Available Article is devoted to optimization problem of theoretical and methodical students knowledge's within the pale of sparring discipline "Physical education". Author offers to posit valeological approach in acquirement of knowledge's from discipline, accepting this as one of motivation rise methods to employments by physical education and propaganda's of healthy mode of life. It is proved that students at the age of 17-25 years old have specific anatomic physiological characteristics, so physical education must favour students' organism forming.

  4. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.

    2016-02-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  5. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    Science.gov (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  6. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    Science.gov (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  7. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest

    2016-02-01

    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  8. Methods and models in mathematical biology deterministic and stochastic approaches

    CERN Document Server

    Müller, Johannes

    2015-01-01

    This book developed from classes in mathematical biology taught by the authors over several years at the Technische Universität München. The main themes are modeling principles, mathematical principles for the analysis of these models, and model-based analysis of data. The key topics of modern biomathematics are covered: ecology, epidemiology, biochemistry, regulatory networks, neuronal networks, and population genetics. A variety of mathematical methods are introduced, ranging from ordinary and partial differential equations to stochastic graph theory and  branching processes. A special emphasis is placed on the interplay between stochastic and deterministic models.

  9. Separating physical and biological controls on evapotranspiration fluctuations in a teak plantation subjected to monsoonal rainfall

    Science.gov (United States)

    Igarashi, Y.; Katul, G. G.; Kumagai, T.; Yoshifuji, N.; Sato, T.; Tanaka, N.; Tanaka, K.; Fujinami, H.; Chatchai, T.; Suzuki, M.

    2014-12-01

    Evapotranspiration (ET), especially in the mainland of the Indochina peninsula, can impact and is impacted by the Asian monsoonal (AM) system, thereby prompting interest in its long-term variability. To separate physical and biological factors controlling ET variability in a tropical deciduous forest under the AM influence, 7-year eddy-covariance and ancillary measurements were collected and analyzed. The 7-year mean rainfall (Pr) and ET along with their standard deviations were 1335 ± 256 and 1027 ± 77.9 mm (about 77% of Pr), respectively, suggesting close coupling between these two hydrologic fluxes. However, other physical and biological drivers de-couple seasonal and annual variations of ET from Pr. To explore them, a big-leaf model complemented by perturbation analysis was employed. The big-leaf model agreed well with measured ET at daily to multi-year time scales, lending confidence in its skill to separate biological from physical controls on ET. Using this formulation, both first-order and second-order Taylor series expansion of total ET derivatives were applied to the big-leaf model and compare with measured changes in ET (dET). Higher-order and joint-terms in the second-order expansion were necessary for matching measured and analyzed dET. Vapor pressure deficit (D) was the primary external physical controlling driver on ET. The leaf area index (LAI) and bulk stomatal conductance (gs) were shown to be the main significant biological drivers on the transpiration component of ET. It can be surmised that rainfall variability controls long-term ET through physical (mainly D) and biological (mainly LAI and gs) in this ecosystem.

  10. Biological effects of radiation in combination with other physical, chemical or biological agents. Annex L

    International Nuclear Information System (INIS)

    This Annex considers the combined action of radiation with potentially important environmental conditions. Since there is a scarcity of systematic data on which an analysis of combined effects can be based, this Annex will be more hypothetical and will attempt to suggest definitions, to identify suitable methods of analysis, to select from a large amount of diffuse information the conditions and the data of importance for further consideration and to provide suggestions for future research. For humans in environmental circumstances the UNSCEAR Committee has been unable to document any clear case of synergistic interaction between radiation and other agents, which could lead to substantial modifications of the risk estimates for significant sections of the population

  11. Biological characteristics of crucian by quantitative inspection method

    Science.gov (United States)

    Chu, Mengqi

    2015-04-01

    Biological characteristics of crucian by quantitative inspection method Through quantitative inspection method , the biological characteristics of crucian was preliminary researched. Crucian , Belongs to Cypriniformes, Cyprinidae, Carassius auratus, is a kind of main plant-eating omnivorous fish,like Gregarious, selection and ranking. Crucian are widely distributed, perennial water all over the country all have production. Determine the indicators of crucian in the experiment, to understand the growth, reproduction situation of crucian in this area . Using the measured data (such as the scale length ,scale size and wheel diameter and so on) and related functional to calculate growth of crucian in any one year.According to the egg shape, color, weight ,etc to determine its maturity, with the mean egg diameter per 20 eggs and the number of eggs per 0.5 grams, to calculate the relative and absolute fecundity of the fish .Measured crucian were female puberty. Based on the relation between the scale diameter and length and the information, linear relationship between crucian scale diameter and length: y=1.530+3.0649. From the data, the fertility and is closely relative to the increase of age. The older, the more mature gonad development. The more amount of eggs. In addition, absolute fecundity increases with the pituitary gland.Through quantitative check crucian bait food intake by the object, reveals the main food, secondary foods, and chance food of crucian ,and understand that crucian degree of be fond of of all kinds of bait organisms.Fish fertility with weight gain, it has the characteristics of species and populations, and at the same tmes influenced by the age of the individual, body length, body weight, environmental conditions (especially the nutrition conditions), and breeding habits, spawning times factors and the size of the egg. After a series of studies of crucian biological character, provide the ecological basis for local crucian's feeding, breeding

  12. Field theoretical methods in chemical physics

    International Nuclear Information System (INIS)

    The language accompanying the use of creation and annihilation operators is found in many scientific fields. The author attempts to bring together the foundations upon which the many and varied applications of field theory have been built. It is demonstrated that the mathematics of second quantization is not limited to quantum mechanics and is a feature of any linear differential equation. Subsequent chapters are: time dependence in field theory; principle of second quantization and statistical mechanics; theory of Green's functions - nomenclature and perturbational calculation; summation of the perturbation expansion; the theory of response functions; applications of the Green's function method to the problems of atomic and molecular structure; application of the Green's function method to spectroscopy. (Auth.)

  13. Tritium in the Physical and Biological Sciences. Vol. II. Proceedings of the Symposium on the Detection and Use of Tritium in the Physical and Biological Sciences

    International Nuclear Information System (INIS)

    The use of tritium for research in physics, chemistry, biology and hydrology has in recent years become increasingly important. It was for this reason that the first international conference to discuss the progress of new developments was organized by the IAEA in conjunction with the Joint Commission on Applied Radioactivity and held from 3 — 10 May 1961, in Vienna. The first five sessions of the Symposium were devoted to the use of tritium in hydrology, physics and chemistry. Special emphasis was laid on the role of tritium as a tracer in hydrology, especially in the study of water movement. The establishment and improvement of counting and detection techniques to facilitate the application of tritium as a tracer was another aspect discussed in this part of the proceedings. Papers were read on the preparation of tritiated compounds and it was generally agreed that further clarification of the mechanism of various techniques, and of the Wilzbach gas exposure technique in particular, would lead to further developments in the synthesis of a number of tritium compounds important in biology. Other papers were concerned with tritium applications to studies of the mechanism of some chemical reactions together with the effects of tritium isotopes. During the second part of the Symposium the biological applications of tritium and tritiated compounds were discussed. These included general problems connected with the biological uses of tritium and the radiation effects of tritium on living organisms such as viruses, bacteria and cancer cells. The value of tritium in biological studies became apparent because of the ease with which a large number of metabolically active compounds such as hormones, vitamins and other important constituents in the body can be labelled with tritium. Tritium is also a weak beta-emitter and autoradiographs of tissues and single cells containing tritium-labelled compounds allow an excellent localization of the tracer. The Symposium was attended

  14. Physical design method of MPSoC

    Institute of Scientific and Technical Information of China (English)

    LIU Peng; XIA Bing-jie; TENG Zhao-wei

    2007-01-01

    Floorplan, clock network and power plan are crucial steps in deep sub-micron system-on-chip design. A novel diagonal floorplan is integrated to enhance the data sharing between different cores in system-on-chip. Custom clock network containing hand-adjusted buffers and variable routing rules is constructed to realize balanced synchronization. Effective power plan considering both IR drop and electromigration achieves high utilization and maintains power integrity in our MediaSoC. Using such methods, deep sub-micron design challenges are managed under a fast prototyping methodology, which greatly shortens the design cycle.

  15. Microbeam radiation therapy. Physical and biological aspects of a new cancer therapy and development of a treatment planning system

    International Nuclear Information System (INIS)

    Microbeam Radiation Therapy (MRT) is a novel treatment strategy against cancer. Highly brilliant synchrotron radiation is collimated to parallel, a few micrometre wide, planar beams and used to irradiate malignant tissues with high doses. The applied peak doses are considerably higher than in conventional radiotherapy, but valley doses between the beams remain underneath the established tissue tolerance. Previous research has shown that these beam geometries spare normal tissue, while being effective in tumour ablation. In this work physical and biological aspects of the therapy were investigated. A therapy planning system was developed for the first clinical treatments at the European Synchrotron Radiation Facility in Grenoble (France) and a dosimetry method based on radiochromic films was created to validate planned doses with measurements on a micrometre scale. Finally, experiments were carried out on a cellular level in order to correlate the physically planned doses with the biological damage caused in the tissue. The differences between Monte Carlo dose and dosimetry are less than 10% in the valley and 5% in the peak regions. Developed alternative faster dose calculation methods deviate from the computational intensive MC simulations by less than 15% and are able to determine the dose within a few minutes. The experiments in cell biology revealed an significant influence of intercellular signalling on the survival of cells close to radiation boundaries. These observations may not only be important for MRT but also for conventional radiotherapy.

  16. Microbeam radiation therapy. Physical and biological aspects of a new cancer therapy and development of a treatment planning system

    Energy Technology Data Exchange (ETDEWEB)

    Bartzsch, Stefan

    2014-11-05

    Microbeam Radiation Therapy (MRT) is a novel treatment strategy against cancer. Highly brilliant synchrotron radiation is collimated to parallel, a few micrometre wide, planar beams and used to irradiate malignant tissues with high doses. The applied peak doses are considerably higher than in conventional radiotherapy, but valley doses between the beams remain underneath the established tissue tolerance. Previous research has shown that these beam geometries spare normal tissue, while being effective in tumour ablation. In this work physical and biological aspects of the therapy were investigated. A therapy planning system was developed for the first clinical treatments at the European Synchrotron Radiation Facility in Grenoble (France) and a dosimetry method based on radiochromic films was created to validate planned doses with measurements on a micrometre scale. Finally, experiments were carried out on a cellular level in order to correlate the physically planned doses with the biological damage caused in the tissue. The differences between Monte Carlo dose and dosimetry are less than 10% in the valley and 5% in the peak regions. Developed alternative faster dose calculation methods deviate from the computational intensive MC simulations by less than 15% and are able to determine the dose within a few minutes. The experiments in cell biology revealed an significant influence of intercellular signalling on the survival of cells close to radiation boundaries. These observations may not only be important for MRT but also for conventional radiotherapy.

  17. Coordinating an IPLS class with a biology curriculum: NEXUS/Physics

    Science.gov (United States)

    Redish, Edward

    2014-03-01

    A multi-disciplinary team of scientists has been reinventing the Introductory Physics for Life Scientists (IPLS) course at the University of Maryland. We focus on physics that connects elements common to the curriculum for all life scientists - molecular and cellular biology - with building general scientific competencies, such as mathematical modeling, reasoning from core principles, and multi-representation translation. The prerequisites for the class include calculus, chemistry, and biology. In addition to building the basic ideas of the Newtonian framework, electric currents, and optics, our prerequisites allow us to include topics such as atomic interactions and chemical bonding, random motion and diffusion, thermodynamics (including entropy and free energy), and spectroscopy. Our chemical bonding unit helps students link the view of energy developed in traditional macroscopic physics with the idea of chemical bonding as a source of energy presented in their chemistry and biology classes. Education research has played a central role in our design, as has a strong collaboration between our Discipline-Based Education and the Biophysics Research groups. These elements permit us to combine modern pedagogy with cutting-edge insights into the physics of living systems. Supported in part by a grant from HHMI and the US NSF grant #1122818/.

  18. Mathematical and computational methods in nuclear physics

    International Nuclear Information System (INIS)

    The lectures, covering various aspects of the many-body problem in nuclei, review present knowledge and include some unpublished material as well. Bohigas and Giannoni discuss the fluctuation properties of spectra of many-body systems by means of random matrix theories, and the attempts to search for quantum mechanical manifestations of classical chaotic motion. The role of spectral distributions (expressed as explicit functions of the microscopic matrix elements of the Hamiltonian) in the statistical spectroscopy of nuclear systems is analyzed by French. Zucker, after a brief review of the theoretical basis of the shell model, discusses a reformulation of the theory of effective interactions and gives a survey of the linked cluster theory. Goeke's lectures center on the mean-field methods, particularly TDHF, used in the investigation of the large-amplitude nuclear collective motion, pointing out both the successes and failures of the theory

  19. Physical, chemical and biological characterization of six biochars produced for the remediation of contaminated sites.

    Science.gov (United States)

    Denyes, Mackenzie J; Parisien, Michèle A; Rutter, Allison; Zeeb, Barbara A

    2014-01-01

    The physical and chemical properties of biochar vary based on feedstock sources and production conditions, making it possible to engineer biochars with specific functions (e.g. carbon sequestration, soil quality improvements, or contaminant sorption). In 2013, the International Biochar Initiative (IBI) made publically available their Standardized Product Definition and Product Testing Guidelines (Version 1.1) which set standards for physical and chemical characteristics for biochar. Six biochars made from three different feedstocks and at two temperatures were analyzed for characteristics related to their use as a soil amendment. The protocol describes analyses of the feedstocks and biochars and includes: cation exchange capacity (CEC), specific surface area (SSA), organic carbon (OC) and moisture percentage, pH, particle size distribution, and proximate and ultimate analysis. Also described in the protocol are the analyses of the feedstocks and biochars for contaminants including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), metals and mercury as well as nutrients (phosphorous, nitrite and nitrate and ammonium as nitrogen). The protocol also includes the biological testing procedures, earthworm avoidance and germination assays. Based on the quality assurance / quality control (QA/QC) results of blanks, duplicates, standards and reference materials, all methods were determined adequate for use with biochar and feedstock materials. All biochars and feedstocks were well within the criterion set by the IBI and there were little differences among biochars, except in the case of the biochar produced from construction waste materials. This biochar (referred to as Old biochar) was determined to have elevated levels of arsenic, chromium, copper, and lead, and failed the earthworm avoidance and germination assays. Based on these results, Old biochar would not be appropriate for use as a soil amendment for carbon sequestration, substrate quality

  20. Methods of biological dosimetry employing chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    2000-01-01

    Methods and compositions for staining based upon nucleic acid sequence that employ nucleic acid probes are provided. Said methods produce staining patterns that can be tailored for specific cytogenetic analyses. Said probes are appropriate for in situ hybridization and stain both interphase and metaphase chromosomal material with reliable signals. The nucleic acid probes are typically of a complexity greater than 50 kb, the complexity depending upon the cytogenetic application. Methods are provided to disable the hybridization capacity of shared, high copy repetitive sequences and/or remove such sequences to provide for useful contrast. Still further methods are provided to produce chromosome-specific staining reagents which are made specific to the targeted chromosomal material, which can be one or more whole chromosomes, one or more regions on one or more chromosomes, subsets of chromosomes and/or the entire genome. Probes and test kits are provided for use in tumor cytogenetics, in the detection of disease related loci, in analysis of structural abnormalities, such as translocations, and for biological dosimetry. Further, methods and prenatal test kits are provided to stain targeted chromosomal material of fetal cells, including fetal cells obtained from maternal blood. Still further, the invention provides for automated means to detect and analyse chromosomal abnormalities.

  1. Physical properties and biological activities of hesperetin and naringenin in complex with methylated β-cyclodextrin

    Directory of Open Access Journals (Sweden)

    Waratchada Sangpheak

    2015-12-01

    Full Text Available The aim of this work is to improve physical properties and biological activities of the two flavanones hesperetin and naringenin by complexation with β-cyclodextrin (β-CD and its methylated derivatives (2,6-di-O-methyl-β-cyclodextrin, DM-β-CD and randomly methylated-β-CD, RAMEB. The free energies of inclusion complexes between hesperetin with cyclodextrins (β-CD and DM-β-CD were theoretically investigated by molecular dynamics simulation. The free energy values obtained suggested a more stable inclusion complex with DM-β-CD. The vdW force is the main guest–host interaction when hesperetin binds with CDs. The phase solubility diagram showed the formation of a soluble complex of AL type, with higher increase in solubility and stability when hesperetin and naringenin were complexed with RAMEB. Solid complexes were prepared by freeze-drying, and the data from differential scanning calorimetry (DSC confirmed the formation of inclusion complexes. The data obtained by the dissolution method showed that complexation with RAMEB resulted in a better release of both flavanones to aqueous solution. The flavanones-β-CD/DM-β-CD complexes demonstrated a similar or a slight increase in anti-inflammatory activity and cytotoxicity towards three different cancer cell lines. The overall results suggested that solubilities and bioactivities of both flavanones were increased by complexation with methylated β-CDs.

  2. Topological data analysis: A promising big data exploration tool in biology, analytical chemistry and physical chemistry.

    Science.gov (United States)

    Offroy, Marc; Duponchel, Ludovic

    2016-03-01

    An important feature of experimental science is that data of various kinds is being produced at an unprecedented rate. This is mainly due to the development of new instrumental concepts and experimental methodologies. It is also clear that the nature of acquired data is significantly different. Indeed in every areas of science, data take the form of always bigger tables, where all but a few of the columns (i.e. variables) turn out to be irrelevant to the questions of interest, and further that we do not necessary know which coordinates are the interesting ones. Big data in our lab of biology, analytical chemistry or physical chemistry is a future that might be closer than any of us suppose. It is in this sense that new tools have to be developed in order to explore and valorize such data sets. Topological data analysis (TDA) is one of these. It was developed recently by topologists who discovered that topological concept could be useful for data analysis. The main objective of this paper is to answer the question why topology is well suited for the analysis of big data set in many areas and even more efficient than conventional data analysis methods. Raman analysis of single bacteria should be providing a good opportunity to demonstrate the potential of TDA for the exploration of various spectroscopic data sets considering different experimental conditions (with high noise level, with/without spectral preprocessing, with wavelength shift, with different spectral resolution, with missing data). PMID:26873463

  3. Biological and chemical-physical properties of root-end filling materials: A comparative study

    Directory of Open Access Journals (Sweden)

    Matteo Ceci

    2015-01-01

    Full Text Available Aim: The purpose of the study is to evaluate and compare the biological and chemical-physical properties of four different root-end filling materials. Materials and Methods: Cytotoxicity towards murine odontoblasts cells (MDPC-23 was evaluated using the Transwell insert methodology by Alamar blue test. Streptococcus salivarius, S. sanguis, and S. mutans strains were selected to evaluate the antimicrobial activity by agar disc diffusion test. Solubility was determined after 24 h and 2 months. pH values were measured after 3 and 24 h. To evaluate radiopacity, all materials were scanned on a GE Healthcare Lunar Prodigy. Results: Excellent percentage of vitality were obtained by mineral trioxide aggregate (MTA-based materials and Biodentine. MTA-Angelus, ProRoot MTA, and Intermediate Restorative Material (IRM showed the highest values for the inhibition zones when tested for S. mutans, while Biodentine showed the largest inhibition zone when tested for S. sanguis. All the materials fulfilled the requirements of the International Standard 6876, demonstrating low solubility with a weight loss of less than 3%. No significant reduction in pH value was demonstrated after 24 h. ProRoot MTA and MTA-Angelus showed the highest values of radiographic density. Conclusions: The differences showed by the root-end filling materials tested do not cover completely the ideal clinical requests.

  4. DNA as information: at the crossroads between biology, mathematics, physics and chemistry

    Science.gov (United States)

    2016-01-01

    On the one hand, biology, chemistry and also physics tell us how the process of translating the genetic information into life could possibly work, but we are still very far from a complete understanding of this process. On the other hand, mathematics and statistics give us methods to describe such natural systems—or parts of them—within a theoretical framework. Also, they provide us with hints and predictions that can be tested at the experimental level. Furthermore, there are peculiar aspects of the management of genetic information that are intimately related to information theory and communication theory. This theme issue is aimed at fostering the discussion on the problem of genetic coding and information through the presentation of different innovative points of view. The aim of the editors is to stimulate discussions and scientific exchange that will lead to new research on why and how life can exist from the point of view of the coding and decoding of genetic information. The present introduction represents the point of view of the editors on the main aspects that could be the subject of future scientific debate. PMID:26857674

  5. Physical properties and biological activities of hesperetin and naringenin in complex with methylated β-cyclodextrin

    Science.gov (United States)

    Sangpheak, Waratchada; Kicuntod, Jintawee; Schuster, Roswitha; Rungrotmongkol, Thanyada; Wolschann, Peter; Kungwan, Nawee; Viernstein, Helmut

    2015-01-01

    Summary The aim of this work is to improve physical properties and biological activities of the two flavanones hesperetin and naringenin by complexation with β-cyclodextrin (β-CD) and its methylated derivatives (2,6-di-O-methyl-β-cyclodextrin, DM-β-CD and randomly methylated-β-CD, RAMEB). The free energies of inclusion complexes between hesperetin with cyclodextrins (β-CD and DM-β-CD) were theoretically investigated by molecular dynamics simulation. The free energy values obtained suggested a more stable inclusion complex with DM-β-CD. The vdW force is the main guest–host interaction when hesperetin binds with CDs. The phase solubility diagram showed the formation of a soluble complex of AL type, with higher increase in solubility and stability when hesperetin and naringenin were complexed with RAMEB. Solid complexes were prepared by freeze-drying, and the data from differential scanning calorimetry (DSC) confirmed the formation of inclusion complexes. The data obtained by the dissolution method showed that complexation with RAMEB resulted in a better release of both flavanones to aqueous solution. The flavanones-β-CD/DM-β-CD complexes demonstrated a similar or a slight increase in anti-inflammatory activity and cytotoxicity towards three different cancer cell lines. The overall results suggested that solubilities and bioactivities of both flavanones were increased by complexation with methylated β-CDs. PMID:26877798

  6. DNA as information: at the crossroads between biology, mathematics, physics and chemistry.

    Science.gov (United States)

    Cartwright, Julyan H E; Giannerini, Simone; González, Diego L

    2016-03-13

    On the one hand, biology, chemistry and also physics tell us how the process of translating the genetic information into life could possibly work, but we are still very far from a complete understanding of this process. On the other hand, mathematics and statistics give us methods to describe such natural systems-or parts of them-within a theoretical framework. Also, they provide us with hints and predictions that can be tested at the experimental level. Furthermore, there are peculiar aspects of the management of genetic information that are intimately related to information theory and communication theory. This theme issue is aimed at fostering the discussion on the problem of genetic coding and information through the presentation of different innovative points of view. The aim of the editors is to stimulate discussions and scientific exchange that will lead to new research on why and how life can exist from the point of view of the coding and decoding of genetic information. The present introduction represents the point of view of the editors on the main aspects that could be the subject of future scientific debate. PMID:26857674

  7. Salt marsh response to the effects of physical and biological processes

    Science.gov (United States)

    Roner, Marcella; D'Alpaos, Andrea; Ghinassi, Massimiliano; Franceschinis, Erica; Realdon, Nicola; Marani, Marco

    2014-05-01

    Salt marshes are widespread features of the tidal landscape governed by the interacting physical and biological processes. These crucially important ecosystems provide valuable services and are currently threatened by the effects of increasing rates of relative sea level rise (RSLR) and decreasing sediment supply. Although a few studies have analyzed the biomorphological evolution of salt marsh systems, a complete understanding of the two-way feedbacks between physical and biological processes is still lacking. The temporal evolution of marsh elevation is governed by the balance between inorganic and organic accretion rates, and the rate of RSLR. Studies based on field observations and modeling suggest that, in equilibrium conditions, marsh inorganic accretion rates, and the related platform elevations, decrease with distance from the main creek whereas the organic deposition gradually increases. In order to analyze salt marsh responses to the effect of physical and biological processes, about 100 sediment samples were collected on the San Felice salt marsh, Venice Lagoon. For each sample, local coordinates, surface elevations and vegetation cover were detected, whereas inorganic and organic sediment content, together with grain size distribution, were determined and analyzed. Loss On Ignition (LOI) and a double treatment with H2O2 and NaClO, were used to estimate the amount of organic matter in each sample. Particle size analysis was carried out on the inorganic fraction with a Mastersizer that uses laser diffraction techniques to measure the grain size. Our results show that the San Felice salt marsh is characterized by a concave-up profile, as commonly displayed by marshes worldwide. Marsh elevation is highest along the boundary and decreases toward the inner marsh. The inorganic deposition, which is maximum along the marsh edge, decreases with distance from the channel network, because as water moves across the marsh, the velocity is reduced and sediment

  8. The Biology Of Physics: What The Brain Reveals About Our Understanding Of The Physical World

    Science.gov (United States)

    Dunbar, Kevin Niall

    2009-11-01

    Fundamental concepts in physics such as Newtonian mechanics are surprisingly difficult to learn and discover. Over the past decade have been using an educational neuroscience approach to science education using a combination of ecologically naturalistic situations, classroom settings, and neuroimaging methodologies to investigate the different ways that scientific concepts are invoked or activated in different contexts. In particular, we have sought to determine how networks of brain regions that are highly sensitive to features of the context in which they are used are involved in the use of scientific concepts. We have found that some concepts in physics that are highly tuned to perception are often inhibited in experts (with increased activations in error detection and inhibitory networks of the prefrontal cortex) rather than having undergone a wholesale conceptual reorganization. Other, concepts, such as those involved in perceptual causality can activate highly diverse brain regions, depending on task instructions. For example, when students are shown movies of balls colliding, we find increased activation in the right parietal lobe, yet when the students see the exact same movies and are told that these are positively charged particles repulsing we find increased activations in the temporal lobe that is consistent with the students retrieving semantic information. We also see similar see similar changes in activation patterns in students learning about phase shifts in chemistry classes. A key component of both students and scientists' discourse and reasoning is analogical thinking. Our recent fMRI work indicates that categorization is a key component of this type of reasoning that helps bind superficially different concepts together in the service of reasoning about the causes of unexpected findings. Taken together, these results are allowing us to make insights into the contextually relevant networks of knowledge that are activated during learning. This work

  9. Physics with MAPLE the computer algebra resource for mathematical methods in physics

    CERN Document Server

    Wang, Frank Y

    2006-01-01

    Written by an experienced physicist who is active in applying computer algebra to relativistic astrophysics and education, this is the resource for mathematical methods in physics using Maple and Mathematica. Through in-depth problems from core courses in the physics curriculum, the author guides students to apply analytical and numerical techniques in mathematical physics, and present the results in interactive graphics. Around 180 simulating exercises are included to facilitate learning by examples.This book is a must-have for students of physics, electrical and mechanical engineering, materials scientists, lecturers in physics, and university libraries

  10. The Learning-Focused Transformation of Biology and Physics Core Courses at the U.S. Air Force Academy

    Science.gov (United States)

    Sagendorf, Kenneth; Noyd, Robert K.; Morris, D. Brent

    2009-01-01

    An institution-wide focus on deep learning has made significant changes in the biology and physics core course curriculum at the U.S. Air Force Academy. The biology course director has reworked course objectives to reflect the learning-focused approach to teaching, while the physics curriculum has adopted new learning outcomes and ways to…

  11. Physical methods for dose determinations in mammography

    International Nuclear Information System (INIS)

    There is small but significant risk of radiation induced carcinogenesis associated with mammography. High quality mammography is the best method of early breast cancer detection. Besides, image as a basic requirement for an effective diagnosis, radiation protection principles require the radiation dose to the imaged tissue to be as low as compatible with required image quality. Glandular tissues is the most radiosensitive, thus the evaluation of Mean Glandular Dose (MGD) is the most relevant factor for estimation of radiation risk as well as the comparison of performance at different mammographic machines. MGD was estimated using Entrance Surface Air KERMA at the breast surface Kf measured free in air and appropriate conversation factors. Under evaluation were eight mammographic machines at institute of radiology, Skopje and mammographic machines at the Health's centers in Vevchani, Bitola, Prilep, Negotino and Shtip. Estimated values of MGD do not exceed the European reference level (<2mGy), but it can not be generally concluded for all mammography units in Macedonia, until their examination. In the near future all mammography units will be subject of Q C tests and dose measurements. (Author)

  12. Using the case-study method in teaching college physics

    CERN Document Server

    Burko, Lior M

    2016-01-01

    The case-study teaching method has a long history (starting at least with Socrates), and wide current use in business schools, medical schools, law schools, and a variety of other disciplines. However, relatively little use is made of it in the physical sciences, specifically in physics or astronomy. The case-study method should be considered by physics faculty as part of the effort to transition the teaching of college physics from the traditional frontal-lecture format to other formats that enhance active student participation. In this paper we endeavor to interest physics instructors in the case-study method, and hope that it would also serve as a call for more instructors to produce cases that they use in their own classes and that can also be adopted by other instructors.

  13. Effective Teaching Methods--Project-based Learning in Physics

    Science.gov (United States)

    Holubova, Renata

    2008-01-01

    The paper presents results of the research of new effective teaching methods in physics and science. It is found out that it is necessary to educate pre-service teachers in approaches stressing the importance of the own activity of students, in competences how to create an interdisciplinary project. Project-based physics teaching and learning…

  14. Method of a Generalized Physical Property in the Crystal Physics Problems

    Science.gov (United States)

    Davydov, V. N.; Lugina, N. É.

    2016-06-01

    A method is proposed for determining the crystallographic directions in crystals of various point symmetry, along which the combination of physical properties of various ranks and Curie symmetry gets a predetermined value. The method is demonstrated for the combination of the second-rank tensors describing optical and thermal properties of crystals of the monoclinic system. The possibility of using the proposed method for the physical properties of high ranks is demonstrated.

  15. Exergames: neuroplastic hypothesis about cognitive improvement and biological effects on physical function of institutionalized older persons

    Science.gov (United States)

    Monteiro-Junior, Renato Sobral; Vaghetti, César Augusto Otero; Nascimento, Osvaldo José M.; Laks, Jerson; Deslandes, Andrea Camaz

    2016-01-01

    Exergames can be considered a dual task because the games are performed by a man-videogame interface, requiring cognitive and motor functions simultaneously. Although the literature has shown improvements of cognitive and physical functions due to exergames, the intrinsic mechanisms involved in these functional changes have still not been elucidated. The aims of the present study were (1) to demonstrate the known biological mechanisms of physical exercise regarding muscle adaptation and establish a relationship with exergames; and (2) to present a neurobiological hypothesis about the neuroplastic effects of exergames on the cognitive function of institutionalized older persons. These hypotheses are discussed. PMID:27073355

  16. DEGRO 2009. Radiation oncology - medical physics - radiation biology. Abstracts; DEGRO 2009. Radioonkologie - Medizinische Physik - Strahlenbiologie. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-06-15

    The special volume of the journal covers the abstracts of the DEGRO 2009 meeting on radiation oncology, medical physics, and radiation biology, covering the following topics: seldom diseases, gastrointestinal tumors, radiation reactions and radiation protection, medical care and science, central nervous system, medical physics, the non-parvicellular lung carcinomas, ear-nose-and throat, target-oriented radiotherapy plus ''X'', radio-oncology - young academics, lymphomas, mammary glands, modern radiotherapy, life quality and palliative radiotherapy, radiotherapy of the prostate carcinoma, imaging for planning and therapy, the digital documentation in clinics and practical experiences, NMR imaging and tomography, hadrons - actual status in Germany, urinal tract oncology, radiotoxicity.

  17. Exergames: neuroplastic hypothesis about cognitive improvement and biological effects on physical function of institutionalized older persons.

    Science.gov (United States)

    Monteiro-Junior, Renato Sobral; Vaghetti, César Augusto Otero; Nascimento, Osvaldo José M; Laks, Jerson; Deslandes, Andrea Camaz

    2016-02-01

    Exergames can be considered a dual task because the games are performed by a man-videogame interface, requiring cognitive and motor functions simultaneously. Although the literature has shown improvements of cognitive and physical functions due to exergames, the intrinsic mechanisms involved in these functional changes have still not been elucidated. The aims of the present study were (1) to demonstrate the known biological mechanisms of physical exercise regarding muscle adaptation and establish a relationship with exergames; and (2) to present a neurobiological hypothesis about the neuroplastic effects of exergames on the cognitive function of institutionalized older persons. These hypotheses are discussed. PMID:27073355

  18. Modelling the Influence of Shielding on Physical and Biological Organ Doses

    CERN Document Server

    Ballarini, Francesca; Ferrari, Alfredo; Ottolenghi, Andrea; Pelliccioni, Maurizio; Scannicchio, Domenico

    2002-01-01

    Distributions of "physical" and "biological" dose in different organs were calculated by coupling the FLUKA MC transport code with a geometrical human phantom inserted into a shielding box of variable shape, thickness and material. While the expression "physical dose" refers to the amount of deposited energy per unit mass (in Gy), "biological dose" was modelled with "Complex Lesions" (CL), clustered DNA strand breaks calculated in a previous work based on "event-by-event" track-structure simulations. The yields of complex lesions per cell and per unit dose were calculated for different radiation types and energies, and integrated into a version of FLUKA modified for this purpose, allowing us to estimate the effects of mixed fields. As an initial test simulation, the phantom was inserted into an aluminium parallelepiped and was isotropically irradiated with 500 MeV protons. Dose distributions were calculated for different values of the shielding thickness. The results were found to be organ-dependent. In most ...

  19. Research Data in Core Journals in Biology, Chemistry, Mathematics, and Physics.

    Directory of Open Access Journals (Sweden)

    Ryan P Womack

    Full Text Available This study takes a stratified random sample of articles published in 2014 from the top 10 journals in the disciplines of biology, chemistry, mathematics, and physics, as ranked by impact factor. Sampled articles were examined for their reporting of original data or reuse of prior data, and were coded for whether the data was publicly shared or otherwise made available to readers. Other characteristics such as the sharing of software code used for analysis and use of data citation and DOIs for data were examined. The study finds that data sharing practices are still relatively rare in these disciplines' top journals, but that the disciplines have markedly different practices. Biology top journals share original data at the highest rate, and physics top journals share at the lowest rate. Overall, the study finds that within the top journals, only 13% of articles with original data published in 2014 make the data available to others.

  20. Natural physical and biological processes compromise the long-term performance of compacted soil caps

    International Nuclear Information System (INIS)

    Compacted soil barriers are components of essentially all caps placed on closed waste disposal sites. The intended functions of soil barriers in waste facility caps include restricting infiltration of water and release of gases and vapors, either independently or in combination with synthetic membrane barriers, and protecting other manmade or natural barrier components. Review of the performance of installed soil barriers and of natural processes affecting their performance indicates that compacted soil caps may function effectively for relatively short periods (years to decades), but natural physical and biological processes can be expected to cause them to fail in the long term (decades to centuries). This paper addresses natural physical and biological processes that compromise the performance of compacted soil caps and suggests measures that may reduce the adverse consequences of these natural failure mechanisms

  1. Resource Letter: Bio-molecular Nano-machines: where Physics, Chemistry, Biology and Technology meet

    OpenAIRE

    Chowdhury, Debashish

    2008-01-01

    Cell is the structural and functional unit of life. This Resource Letter serves as a guide to the literature on nano-machines which drive not only intracellular movements, but also motility of the cell. These machines are usually proteins or macromolecular assemblies which require appropriate fuel for their operations. Although, traditionally, these machines were subjects of investigation in biology and biochemistry, increasing use of the concepts and techniques of physics in recent years hav...

  2. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1985-November 30, 1986

    International Nuclear Information System (INIS)

    This is the annual report of the Radiological Research Laboratory of the Department of Radiation Oncology, Columbia University. The bulk of the research of the Laboratory involves basic and fundamental aims, not confined to radiotherapy. Research carried out in the Laboratory covers the determination of microdosimetry quantities, computer simulation of particle tracks, determination of oncogenic transformation, and the transfection of DNA into cells. The Hallmark of the Laboratory is the interaction between physics and biology

  3. Influence of physical and chemical factors on biological leaching process of copper from printed circuit boards

    OpenAIRE

    Willner, J

    2013-01-01

    The article presents the results of the research regarding the biological leaching of this metal from electronic wastes components in the form of printed circuit boards. The purpose of the study was to evaluate the influence of some physical and chemical factors (e.g. pH, oxidation-reduction potential) on bioleaching process and efficiency of copper transfer from solid phase into solution. Bioleaching experiments were carried out with pure cultures of Acidithiobacillus ferrooxidans. The obtai...

  4. Physical-chemical and biological parameters of two neighbouring post-exploitation clay-pits

    Directory of Open Access Journals (Sweden)

    S. Celewicz-Gołdyn

    2006-09-01

    Full Text Available The aim of the study was to determine the physical-chemical and biological (aquatic vegetation cover and plankton structure parameters of two post-exploitation clay-pits. As a result of the study it was found that even though the examined water bodies were situated within a very short distance, were of the same origin and of a similar time of origination, they differed from each other in many aspects.

  5. Emergence and Evolution of Order in Physical, Chemical, and Biological Systems

    Science.gov (United States)

    Swinney, Harry

    2008-10-01

    Do the Great Red Spot of Jupiter and the spirals in a frog egg have anything in common? The sizes are vastly different and the biology of even a simple frog egg is far more complicated than the physics of a fluid. Yet the patterns formed in such systems, differing widely in scale and in the underlying molecular mechanisms, can in many cases be understood from a common approach.

  6. Great Meteor East: an interim report on biological sampling and general relationship to physical oceanography

    International Nuclear Information System (INIS)

    The report deals with work carried out in June/July 1985 on RRS Discovery Cruise 156 to GME. The general physical oceanography of the area and the vertical distribution of chlorophyll a and nutrients are described. Primary production measurements and results are discussed in detail. Biological sampling of benthic and pelagic animals is described together with the subsequent laboratory treatment of the samples and some preliminary data on midwater biomass. (author)

  7. Physical-chemical and biological parameters of two neighbouring post-exploitation clay-pits

    OpenAIRE

    S. Celewicz-Gołdyn; B. Nagengast; N. Kuczyńska-Kippen

    2006-01-01

    The aim of the study was to determine the physical-chemical and biological (aquatic vegetation cover and plankton structure) parameters of two post-exploitation clay-pits. As a result of the study it was found that even though the examined water bodies were situated within a very short distance, were of the same origin and of a similar time of origination, they differed from each other in many aspects.

  8. Physical Activity and Gastrointestinal Cancers: Primary and Tertiary Preventive Effects and Possible Biological Mechanisms

    OpenAIRE

    Karen Steindorf; Dorothea Clauss; Joachim Wiskemann; Schmidt, Martina E

    2015-01-01

    Gastrointestinal cancers account for 37% of all cancer deaths worldwide, underlining the need to further investigate modifiable factors for gastrointestinal cancer risk and prognosis. This review summarizes the corresponding evidence for physical activity (PA), including, briefly, possible biological mechanisms. Despite high public health relevance, there is still a scarcity of studies, especially for tertiary prevention. Besides the convincing evidence of beneficial effects of PA on colon ca...

  9. Nonequilibrium thermodynamics transport and rate processes in physical, chemical and biological systems

    CERN Document Server

    Demirel, Yasar

    2014-01-01

    Natural phenomena consist of simultaneously occurring transport processes and chemical reactions. These processes may interact with each other and may lead to self-organized structures, fluctuations, instabilities, and evolutionary systems. Nonequilibrium Thermodynamics, 3rd edition emphasizes the unifying role of thermodynamics in analyzing the natural phenomena. This third edition updates and expands on the first and second editions by focusing on the general balance equations for coupled processes of physical, chemical, and biological systems. The new edition contains a new chapte

  10. Topics in nonlinear dynamics applications to physics, biology and economic systems

    CERN Document Server

    Mosekilde, Erik

    1997-01-01

    Through a series of examples from physics, engineering, biology and economics, this book illustrates the enormous potential for application of ideas and concepts from nonlinear dynamics and chaos theory. The overlap with examples published in other books is virtually equal to zero. The book takes the reader from detailed studies of bifurcation structures of relativity simple models to pattern formation in spatially extended systems. The book also discusses the different perspectives that nonlinear dynamics brings to different fields of science.

  11. Radiation physics, biophysics, and radiation biology: Progress report, December 1, 1987-November 30, 1988

    International Nuclear Information System (INIS)

    Research at the Radiological Research Laboratory is a blend of physics, chemistry, and biology, involving research at the basic level with the admixture of a small proportion of pragmatic or applied research in support of radiation protection and/or radiation therapy. At the current level of funding, approximately one quarter of the research of the Laboratory could be regarded as in support of radiotherapy, with the remainder addressing more basic issues. The new initiatives have been in two directions. First, there has been an increased emphasis on research in radiation chemistry, inasmuch as this subject which involves the study of free radicals and fast radiation chemistry processes starts to bridge the gap between physics and biology, between the initial deposition of radiant energy and its final expression in terms of biological consequences. Second, the emphasis in the biological research has moved towards studies at the molecular level, with the appointment of new members of staff with expertise in this area. Individual chapters were processed separately for the data base

  12. Effects of timber harvest on river food webs: physical, chemical and biological responses.

    Directory of Open Access Journals (Sweden)

    J Timothy Wootton

    Full Text Available I compared physical, chemical and biological characteristics of nine rivers running through three timber harvest regimes to investigate the effects of land use on river ecosystems, to determine whether these corresponded to changes linked with downstream location, and to compare the response of different types of indicator variables. Physical variables changed with downstream location, but varied little with timber harvest. Most chemical variables increased strongly with timber harvest, but not with downstream location. Most biological variables did not vary systematically with either timber harvest or downstream location. Dissolved organic carbon did not vary with timber harvest or downstream location, but correlated positively with salmonid abundance. Nutrient manipulations revealed no general pattern of nutrient limitation with timber harvest or downstream location. The results suggest that chemical variables most reliably indicate timber harvest impact in these systems. The biological variables most relevant to human stakeholders were surprisingly insensitive to timber harvest, however, apparently because of decoupling from nutrient responses and unexpectedly weak responses by physical variables.

  13. Individual and interpersonal risk factors for physical intimate partner violence perpetration by biological sex and ethnicity.

    Science.gov (United States)

    Renner, Lynette M; Whitney, Stephen D; Vasquez, Matthew

    2015-01-01

    Intimate partner violence (IPV) is a public health problem that reaches across age, sex, and ethnicity. In this study, we examined risk factors for physical IPV perpetration among young adult males and females from four ethnic groups. Data were taken from Waves 1-3 of the National Longitudinal Study of Adolescent Health (Add Health). The sample included 10,141 Wave 3 respondents (ages ranged from 18-27 years old) who reported being in a current romantic relationship. Physical IPV perpetration was reported by 14.10% of White, 23.28% of Black, 18.82% of Latino, and 18.02% of Asian males. Physical IPV perpetration was reported by 19.01% of White, 24.80% of Black, 25.97% of Latina, and 19.21% of Asian females. Following an ecological framework, proximal risk factors at intrapersonal and interpersonal levels were included in the analyses. Despite finding fairly consistent percentage of physical IPV perpetration across sample groups, the risk factors for physical IPV perpetration were rather uncommon across sex and ethnicity. Only 1 factor--psychological IPV perpetration toward a romantic partner--was consistently associated with physical IPV perpetration across all groups. Our findings have implications for tailoring prevention and intervention efforts toward risk factors of physical IPV perpetration that are uniquely associated with biological sex and ethnicity. PMID:25774417

  14. Unfolding methods in high-energy physics experiments

    International Nuclear Information System (INIS)

    Distributions measured in high-energy physics experiments are often distorted or transformed by limited acceptance and finite resolution of the detectors. The unfolding of measured distributions is an important, but due to inherent instabilities a very difficult problem. Methods for unfolding, applicable for the analysis of high-energy physics experiments, and their properties are discussed. An introduction is given to the method of regularization. (orig.)

  15. Evolution of a physical and biological front from upwelling to relaxation

    Science.gov (United States)

    Zhang, Yanwu; Bellingham, James G.; Ryan, John P.; Godin, Michael A.

    2015-10-01

    Fronts influence the structure and function of coastal marine ecosystems. Due to the complexity and dynamic nature of coastal environments and the small scales of frontal gradient zones, frontal research is difficult. To advance this challenging research we developed a method enabling an autonomous underwater vehicle (AUV) to detect and track fronts, thereby providing high-resolution observations in the moving reference frame of the front itself. This novel method was applied to studying the evolution of a frontal zone in the coastal upwelling environment of Monterey Bay, California, through a period of variability in upwelling intensity. Through 23 frontal crossings in four days, the AUV detected the front using real-time analysis of vertical thermal stratification to identify water types and the front between them, and the vehicle tracked the front as it moved more than 10 km offshore. The physical front coincided with a biological front between strongly stratified phytoplankton-enriched water inshore of the front, and weakly stratified phytoplankton-poor water offshore of the front. While stratification remained a consistent identifier, conditions on both sides of the front changed rapidly as regional circulation responded to relaxation of upwelling winds. The offshore water type transitioned from relatively cold and saline upwelled water to relatively warm and fresh coastal transition zone water. The inshore water type exhibited an order of magnitude increase in chlorophyll concentrations and an associated increase in oxygen and decrease in nitrate. It also warmed and freshened near the front, consistent with the cross-frontal exchange that was detected in the high-resolution AUV data. AUV-observed cross-frontal exchanges beneath the surface manifestation of the front emphasize the importance of AUV synoptic water column surveys in the frontal zone.

  16. How Can We Improve Problem Solving in Undergraduate Biology? Applying Lessons from 30 Years of Physics Education Research

    OpenAIRE

    Hoskinson, A.-M.; Caballero, M.D. (M.D.); Knight, J.K.

    2013-01-01

    If students are to successfully grapple with authentic, complex biological problems as scientists and citizens, they need practice solving such problems during their undergraduate years. Physics education researchers have investigated student problem solving for the last three decades. Although physics and biology problems differ in structure and content, the instructional purposes align closely: explaining patterns and processes in the natural world and making predictions about physical and ...

  17. Some biological side effects in laboratories of the plasma physics and nuclear fusion research school of Iran

    Directory of Open Access Journals (Sweden)

    Shervin Goudarzi

    2010-06-01

    Full Text Available Objective: Reporting some biological side effects with special attention to reproductive points which were seen after different experiments in laboratories of the Plasma Physics & Nuclear Fusion in atomic energy organization of Iran.Materials and methods: Dosimeter analysis and interpretation of biological side effects of research studies in nuclear fusion laboratories.Results: In the last 3 decades, neglecting the principles of the radiation protection has been confirmed in laboratories of the plasma physics and nuclear fusion research school of Iran, especially on DAMAVAND and ALVAND Tokamaks and DENA Plasma Focus.  Also a series of biological side effects such as alopecia and thyroid function disorders, oligospermia and stomach cancer have been seen in personnel working in related laboratories.Conclusion: As in our laboratories transportation of the peripheral components such to further distances from the main devices seems not to be cost effective. The level of the absorbed dose of the personnel must be decreased in other ways such as: lowering the number of attended shots for each person and proper shielding

  18. The Effect of Sterilization Methods on the Physical Properties of Silk Sericin Scaffolds

    OpenAIRE

    Siritientong, Tippawan; Srichana, Teerapol; Aramwit, Pornanong

    2011-01-01

    Protein-based biomaterials respond differently to sterilization methods. Since protein is a complex structure, heat, or irradiation may result in the loss of its physical or biological properties. Recent investigations have shown that sericin, a degumming silk protein, can be successfully formed into a 3-D scaffolds after mixing with other polymers which can be applied in skin tissue engineering. The objective of this study was to investigate the effectiveness of ethanol, ethylene oxide (EtO)...

  19. Biologic data, models, and dosimetric methods for internal emitters

    International Nuclear Information System (INIS)

    The absorbed radiation dose from internal emitters has been and will remain a pivotal factor in assessing risk and therapeutic utility in selecting radiopharmaceuticals for diagnosis and treatment. Although direct measurements of absorbed dose and dose distributions in vivo have been and will continue to be made in limited situations, the measurement of the biodistribution and clearance of radiopharmaceuticals in human subjects and the use of this data is likely to remain the primary means to approach the calculation and estimation of absorbed dose from internal emitters over the next decade. Since several approximations are used in these schema to calculate dose, attention must be given to inspecting and improving the application of this dosimetric method as better techniques are developed to assay body activity and as more experience is gained in applying these schema to calculating absorbed dose. Discussion of the need for considering small scale dosimetry to calculate absorbed dose at the cellular level will be presented in this paper. Other topics include dose estimates for internal emitters, biologic data mathematical models and dosimetric methods employed. 44 refs

  20. Multi-Level iterative methods in computational plasma physics

    International Nuclear Information System (INIS)

    Plasma physics phenomena occur on a wide range of spatial scales and on a wide range of time scales. When attempting to model plasma physics problems numerically the authors are inevitably faced with the need for both fine spatial resolution (fine grids) and implicit time integration methods. Fine grids can tax the efficiency of iterative methods and large time steps can challenge the robustness of iterative methods. To meet these challenges they are developing a hybrid approach where multigrid methods are used as preconditioners to Krylov subspace based iterative methods such as conjugate gradients or GMRES. For nonlinear problems they apply multigrid preconditioning to a matrix-few Newton-GMRES method. Results are presented for application of these multilevel iterative methods to the field solves in implicit moment method PIC, multidimensional nonlinear Fokker-Planck problems, and their initial efforts in particle MHD

  1. 09091 Executive Summary -- Formal Methods in Molecular Biology

    OpenAIRE

    Breitling, Rainer; Gilbert, David Roger; Heiner, Monika; Priami, Corrado

    2009-01-01

    Formal logical models play an increasing role in the newly emerging field of Systems Biology. Compared to the classical, well-established approach of modeling biological processes using continuous and stochastic differential equations, formal logical models offer a number of important advantages. Many different formal modeling paradigms have been applied to molecular biology, each with its own community, formalisms and tools. In this seminar we brought together modelers from variou...

  2. Global optimization in systems biology: stochastic methods and their applications

    OpenAIRE

    Balsa-Canto, Eva; Banga, Julio R.; Egea, José A.; Villaverde, A. F.; Hijas-Liste, G. M.

    2012-01-01

    Mathematical optimization is at the core of many problems in systems biology: (1) as the underlying hypothesis for model development, (2) in model identification, or (3) in the computation of optimal stimulation procedures to synthetically achieve a desired biological behavior. These problems are usually formulated as nonlinear programing problems (NLPs) with dynamic and algebraic constraints. However the nonlinear and highly constrained nature of systems biology models, together with the usu...

  3. Register indicators of physical endurance of biological objects when running a treadmill and swimming with weights using computer video markerless tracking

    Directory of Open Access Journals (Sweden)

    Datsenko A.V.

    2014-12-01

    Full Text Available Purpose: to study the use of video tracking to assess physical endurance and indicators of biological objects fatigue when running on a treadmill and swimming with the load. Material and methods. Physical endurance evaluated by test facilities for running on a treadmill and swimming with the load. As the object of the studies used laboratory rats. Results. For indicators of physical endurance biological objects isolated areas running track of treadmill and electrical stimulation site, when swimming on the total area of the container isolated subarea near the water surface. With video tracking performed computer timing of finding biological object in different zones of the treadmill and containers for swimming. On the basis of data on the time location rats in a given zone apparatus for running and swimming, obtained in the dynamics of the test of physical endurance, build a "fatigue curves", quantified changes in the indices of hard work, depending on the duration of its execution. Conclusion. Video tracking allows to define the execution of physical work to overflowing with loads of aerobic and mixed aerobic-anaerobic power, establish quantitative indicators of changes in the dynamics of biological objects operability testing with the construction of "fatigue curve" and objectively determine the times of occurrence in experimental animals exhaustion when fails to perform physical work.

  4. Analytical methods to calculate correlation functions in quantum statistical physics

    International Nuclear Information System (INIS)

    In the work there is presented a brief but clear and quite reserved account of two analytical methods to calculate correlation functions in quantum statistical physics, proceeding from the first principles, i.e., the most broadly used at present two-time temperature Green's functions method and a new, so-called 'direct algebraic' method (DAM). The aim of this work is to show on the concrete examples of live the most broadly used models of quantum statistical physics, mathematical and technical clarity and simplicity of DAM and hence its practical value

  5. Exhaled breath analysis: physical methods, instruments, and medical diagnostics

    International Nuclear Information System (INIS)

    This paper reviews the analysis of exhaled breath, a rapidly growing field in noninvasive medical diagnostics that lies at the intersection of physics, chemistry, and medicine. Current data are presented on gas markers in human breath and their relation to human diseases. Various physical methods for breath analysis are described. It is shown how measurement precision and data volume requirements have stimulated technological developments and identified the problems that have to be solved to put this method into clinical practice. (instruments and methods of investigation)

  6. Interactive Methods of Teaching Physics at Technical Universities

    Science.gov (United States)

    Krišták, L'uboš; Nemec, Miroslav; Danihelová, Zuzana

    2014-01-01

    The paper presents results of "non-traditional" teaching of the basic course of Physics in the first year of study at the Technical University in Zvolen, specifically teaching via interactive method enriched with problem tasks and experiments. This paper presents also research results of the use of the given method in conditions of…

  7. A model of heavy ion detection in physical and biological systems

    International Nuclear Information System (INIS)

    Track structure theory (the Katz model) and its application to the detection of heavy ions in physical and biological systems are reviewed. Following the use of a new corrected formula describing the radial distribution of average dose around the path of a heavy ion, based on results of Monte Carlo calculations and on results of experimental measurements, better agreement is achieved between model calculations and experimentally measured relative effectiveness, for enzymatic and viral systems, for the Fricke dosemeter and for alanine and thermoluminescent (TDL-700) dosemeters irradiated with beams of heavy charged particles. From experimentally measured RBE dependences for survival and frequency of neoplastic transformations in a mammalian cell culture irradiated with beams of energetic heavy ions, values of model parameters for these biological endpoints have been extracted, and a model extrapolation to the low-dose region performed. Results of model calculations are then compared with evaluations of the lung cancer hazard in populations exposed to radon and its progeny. The model can be applied to practical phenomenological analysis of radiation damage in solid-state systems and to dosimetry of charged particle and fast neutron beams using a variety of detectors. The model can also serve as a guide in building more basic models of the action of ionizing radiation with physical and biological systems and guide of development of models of radiation risk more relevant than that used presently. 185 refs., 31 figs., 3 tabs. (author)

  8. A coupled physical-biological-chemical model for the Indian Ocean

    Indian Academy of Sciences (India)

    P S Swathi; M K Sharada; K S Yajnik

    2000-12-01

    A coupled physical-biological-chemical model has been developed at C-MMACS. for studying the time- variation of primary productivity and air-sea carbon-dioxide exchange in the Indian Ocean. The physical model is based on the Modular Ocean Model, Version 2 (MOM2) and the biological model describes the nonlinear dynamics of a 7-component marine ecosystem. The chemical model includes dynamical equation for the evolution of dissolved inorganic carbon and total alkalinity. The interaction between the biological and chemical model is through the Redfield ratio. The partial pressure of carbon dioxide pCO2 of the surface layer is obtained from the chemical equilibrium equations of Peng et al 1987. Transfer coefficients for air-sea exchange of CO2 are computed dynamically based on the wind speeds. The coupled model reproduces the high productivity observed in the Arabian Sea off the Somali and Omani coasts during the Southwest (SW) monsoon. The entire Arabian Sea is an outgassing region for CO2 in spite of high productivity with transfer rates as high as 80 m-mol C/m2/day during SW monsoon near the Somali Coast on account of strong winds.

  9. Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO

    International Nuclear Information System (INIS)

    We compare models of radiation transport and biological response to physical and biological dosimetry results from astronauts on the Mir space station. Transport models are shown to be in good agreement with physical measurements and indicate that the ratio of equivalent dose from the Galactic Cosmic Rays (GCR) to protons is about 3/2:1 and that this ratio will increase for exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cells; a track-structure model and the linear-quadratic model with linear energy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement with data for aberrations in lymphocytes of Mir crew members: however there are differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major difference in the models is the increased effectiveness predicted by the track model for low charge and energy ions with LET near 10 keV/μm. The results of our calculations indicate that aluminum shielding, although providing important mitigation of the effects of trapped radiation, provides no protective effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measure until about 100 g/cm2 of material is used

  10. Open water processes of the San Francisco Estuary: From physical forcing to biological responses

    Directory of Open Access Journals (Sweden)

    Wim Kimmerer

    2004-02-01

    Full Text Available This paper reviews the current state of knowledge of the open waters of the San Francisco Estuary. This estuary is well known for the extent to which it has been altered through loss of wetlands, changes in hydrography, and the introduction of chemical and biological contaminants. It is also one of the most studied estuaries in the world, with much of the recent research effort aimed at supporting restoration efforts. In this review I emphasize the conceptual foundations for our current understanding of estuarine dynamics, particularly those aspects relevant to restoration. Several themes run throughout this paper. First is the critical role physical dynamics play in setting the stage for chemical and biological responses. Physical forcing by the tides and by variation in freshwater input combine to control the movement of the salinity field, and to establish stratification, mixing, and dilution patterns throughout the estuary. Many aspects of estuarine dynamics respond to interannual variation in freshwater flow; in particular, abundance of several estuarine-dependent species of fish and shrimp varies positively with flow, although the mechanisms behind these relationships are largely unknown. The second theme is the importance of time scales in determining the degree of interaction between dynamic processes. Physical effects tend to dominate when they operate at shorter time scales than biological processes; when the two time scales are similar, important interactions can arise between physical and biological variability. These interactions can be seen, for example, in the response of phytoplankton blooms, with characteristic time scales of days, to stratification events occurring during neap tides. The third theme is the key role of introduced species in all estuarine habitats; particularly noteworthy are introduced waterweeds and fishes in the tidal freshwater reaches of the estuary, and introduced clams there and in brackish water. The

  11. Climate change and physical disturbance cause similar community shifts in biological soil crusts.

    Science.gov (United States)

    Ferrenberg, Scott; Reed, Sasha C; Belnap, Jayne

    2015-09-29

    Biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface—are fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover. Although there has been long-standing concern over impacts of physical disturbances on biocrusts (e.g., trampling by livestock, damage from vehicles), there is increasing concern over the potential for climate change to alter biocrust community structure. Using long-term data from the Colorado Plateau, we examined the effects of 10 y of experimental warming and altered precipitation (in full-factorial design) on biocrust communities and compared the effects of altered climate with those of long-term physical disturbance (>10 y of replicated human trampling). Surprisingly, altered climate and physical disturbance treatments had similar effects on biocrust community structure. Warming, altered precipitation frequency [an increase of small (1.2 mm) summer rainfall events], and physical disturbance from trampling all promoted early successional community states marked by dramatic declines in moss cover and increases in cyanobacteria cover, with more variable effects on lichens. Although the pace of community change varied significantly among treatments, our results suggest that multiple aspects of climate change will affect biocrusts to the same degree as physical disturbance. This is particularly disconcerting in the context of warming, as temperatures for drylands are projected to increase beyond those imposed as treatments in our study. PMID:26371310

  12. Biological activity of terpene compounds produced by biotechnological methods.

    Science.gov (United States)

    Paduch, Roman; Trytek, Mariusz; Król, Sylwia K; Kud, Joanna; Frant, Maciej; Kandefer-Szerszeń, Martyna; Fiedurek, Jan

    2016-06-01

    Context Biotransformation systems are profitable tools for structural modification of bioactive natural compounds into valuable biologically active terpenoids. Objective This study determines the biological effect of (R)-(+)-limonene and (-)-α-pinene, and their oxygenated derivatives, (a) perillyl alcohol and (S)-(+)- and (R)-(-)-carvone enantiomers and (b) linalool, trans-verbenol and verbenone, respectively, on human colon tumour cells and normal colonic epithelium. Materials and methods Biotransformation procedures and in vitro cell culture tests were used in this work. Cells were incubated for 24 h with terpenes at concentrations of 5-500 μg/mL for NR, MTT, DPPH, and NO assays. IL-6 was determined by ELISA with/without 2 h pre-activation with 10 μg/mL LPS. Results trans-Verbenol and perillyl alcohol, obtained via biotransformation, produced in vitro effect against tumour cells at lower concentrations (IC50 value = 77.8 and 98.8 μg/mL, respectively) than their monoterpene precursors, (R)-(+)-limonene (IC50 value = 171.4 μg/mL) and (-)-α-pinene (IC50 value = 206.3 μg/mL). They also showed lower cytotoxicity against normal cells (IC50 > 500 and > 200 μg/mL, respectively). (S)-(+)-Carvone was 59.4% and 27.1% more toxic to tumour and normal cells, respectively, than the (R)-(-)-enantiomer. (R)-(+)-limonene derivatives decreased IL-6 production from normal cells in media with or without LPS (30.2% and 13.9%, respectively), while (-)-α-pinene derivatives induced IL-6 (verbenone had the strongest effect, 60.2% and 29.1% above control, respectively). None of the terpenes had antioxidative activity below 500 μg/mL. Discussion and conclusions Bioactivity against tumour cells decreased in the following order: alcohols > ketones > hydrocarbons. (R)-(+)-limonene, (-)-α-pinene, and their derivatives expressed diverse activity towards normal and tumour cells with noticeable enantiomeric differences. PMID:26808720

  13. Teleology in biology, chemistry and physics education: what primary teachers should know

    Directory of Open Access Journals (Sweden)

    KOSTAS KAMPOURAKIS

    2007-01-01

    Full Text Available Recent research in cognitive psychology suggests that children develop intuitions that may clash with what is accepted by scientists, thus making certain scientific concepts difficult to understand. Children possess intuitions about design and purpose that make them provide teleological explanations to many different sorts of tasks. One possible explanation for the origin of the bias to view objects as made for something derives from an early sensitivity to intentional agents and to their behavior as intentional object users and object makers. What is important is that teleological explanations may not be exclusively restricted in biological phenomena, as commonly assumed. Consequently, primary school teachers should take that into account when teaching biology, chemistry or physics concepts and try to refrain from enforcing students’ teleological intuitions.

  14. Interactive Methods of Teaching Physics at Technical Universities

    CERN Document Server

    Krišťák, Ľuboš; Danihelová, Zuzana

    2013-01-01

    The papeer presents results of "non-traditional" teaching of basic course of Physics in the first year of study at the Technical University in Zvolen, specifically teaching via interactive method based on an increased focus on problem tasks and experiments. This paper presents also research results of the use of the given method in conditions of Slovak universities and its comparision with traditional methods.

  15. Physical-chemical determinant properties of biological communities in continental semi-arid waters.

    Science.gov (United States)

    da Rocha, Francisco Cleiton; de Andrade, Eunice Maia; Lopes, Fernando Bezerra; de Paula Filho, Francisco José; Filho, José Hamilton Costa; da Silva, Merivalda Doroteu

    2016-08-01

    Throughout human history, water has undergone changes in quality. This problem is more serious in dry areas, where there is a natural water deficit due to climatic factors. The aims of this study, therefore, were (i) to verify correlations between physical attributes, chemical attributes and biological metrics and (ii) from the biological attributes, to verify the similarity between different points of a body of water in a tropical semi-arid region. Samples were collected every 2 months, from July 2009 to July 2011, at seven points. Four physical attributes, five chemical attributes and four biological metrics were investigated. To identify the correlations between the physicochemical properties and the biological metrics, hierarchical cluster analysis (HCA) and canonical correlation analysis (CCA) were applied. Nine classes of phytoplankton were identified, with the predominance of species of cyanobacteria, and ten families of macroinvertebrates. The use of HCA resulted in the formation of three similar groups, showing that it was possible to reduce the number of sampling points when monitoring water quality with a consequent reduction in cost. Group I was formed from the waters at the high end of the reservoir (points P1, P2 and P3), group II by the waters from the middle third (points P4 and P5), and group III by the waters from the lower part of the reservoir (points P6 and P7). Richness of the phytoplanktons Cyanophyceae, Chorophyceae and Bacillariophyceae was the attribute which determined dissimilarity in water quality. Using CCA, it was possible to identify the spatial variability of the physicochemical attributes (TSS, TKN, nitrate and total phosphorus) that most influence the metrics of the macroinvertebrates and phytoplankton present in the water. Low macroinvertebrate diversity, with a predominance of indicator families for deterioration in water quality, and the composition of phytoplankton showing a predominance of cyanobacteria, suggests greater

  16. Usefulness and limits of biological dosimetry based on cytogenetic methods

    International Nuclear Information System (INIS)

    Damage from occupational or accidental exposure to ionising radiation is often assessed by monitoring chromosome aberrations in peripheral blood lymphocytes, and these procedures have, in several cases, assisted physicians in the management of irradiated persons. Thereby, circulating lymphocytes, which are in the G0 stage of the cell cycle are stimulated with a mitogenic agent, usually phytohaemagglutinin, to replicate in vitro their DNA and enter cell division, and are then observed for abnormalities. Comparison with dose response relationships obtained in vitro allows an estimate of exposure based on scoring: - Unstable aberrations by the conventional, well-established analysis of metaphases for chromosome abnormalities or for micronuclei; - So-called stable aberrations by the classical G-banding (Giemsa-Stain-banding) technique or by the more recently developed fluorescent in situ hybridisation (FISH) method using fluorescent-labelled probes for centromeres and chromosomes. Three factors need to be considered in applying such biological dosimetry: (1) Radiation doses in the body are often inhomogeneous. A comparison of the distribution of the observed aberrations among with that expected from a normal poisson distribution can allow conclusions to be made with regard to the inhomogeneity of exposure by means of the so-called contaminated poisson distribution method; however, its application requires a sufficiently large number of aberrations, i.e. an exposure to a rather large dose at a high dose rate. (2) Exposure can occur at a low dose rate (e.g. from spread or lost radioactive sources) rendering a comparison with in vitro exposure hazardous. Dose-effect relationships of most aberrations that were scored, such as translocations, follow a square law. Repair intervening during exposure reduces the quadratic component with decreasing dose rate as exposure is spread over a longer period of time. No valid solution for this problem has yet been developed, although

  17. Usefulness and limits of biological dosimetry based on cytogenetic methods.

    Science.gov (United States)

    Léonard, A; Rueff, J; Gerber, G B; Léonard, E D

    2005-01-01

    Damage from occupational or accidental exposure to ionising radiation is often assessed by monitoring chromosome aberrations in peripheral blood lymphocytes, and these procedures have, in several cases, assisted physicians in the management of irradiated persons. Thereby, circulating lymphocytes, which are in the G0 stage of the cell cycle are stimulated with a mitogenic agent, usually phytohaemagglutinin, to replicate in vitro their DNA and enter cell division, and are then observed for abnormalities. Comparison with dose-response relationships obtained in vitro allows an estimate of exposure based on scoring: Unstable aberrations by the conventional, well-established analysis of metaphases for chromosome abnormalities or for micronuclei; So-called stable aberrations by the classical G-banding (Giemsa-Stain-banding) technique or by the more recently developed fluorescent in situ hybridisation (FISH) method using fluorescent-labelled probes for centromeres and chromosomes. Three factors need to be considered in applying such biological dosimetry: (1) Radiation doses in the body are often inhomogeneous. A comparison of the distribution of the observed aberrations among cells with that expected from a normal poisson distribution can allow conclusions to be made with regard to the inhomogeneity of exposure by means of the so-called contaminated poisson distribution method; however, its application requires a sufficiently large number of aberrations, i.e. an exposure to a rather large dose at a high dose rate. (2) Exposure can occur at a low dose rate (e.g. from spread or lost radioactive sources) rendering a comparison with in vitro exposure hazardous. Dose-effect relationships of most aberrations that were scored, such as translocations, follow a square law. Repair intervening during exposure reduces the quadratic component with decreasing dose rate as exposure is spread over a longer period of time. No valid solution for this problem has yet been developed, although

  18. Physical Training Methods For Mine Rescuers In 2015

    Science.gov (United States)

    Costa, Cristian; Lupu, Lucian; Edelhauser, Eduard

    2015-07-01

    We have studied physical mine rescue training programs and health-related and rescue-related fitness tasks during a mine rescue competition, made in China and Australia and on these basis we have design our own pre physical training method. We have stored the heart rate measured in bites per minute (bpm) during the 2012 year periodical training for 21 mine rescuers. We have designed a physical training procedure based on six training models: Body Building, Method of isometric efforts, Method of Interval Training, Volume variation method, Structured method for basic grip and release and Specific work method. Then we measured again during the 2014 year periodical training, the heart rate for the same mine rescuer having the physical training procedure performed before. We have notice that the trained person have now lower bpm, during the tests that could represent better performances during the rescue actions. Our research were made in the Laboratory for Risk-Rescue Operations of the INCD INSEMEX Petroşani, Romania.

  19. FOREWORD: Third Nordic Symposium on Computer Simulation in Physics, Chemistry, Biology and Mathematics

    Science.gov (United States)

    Kaski, K.; Salomaa, M.

    1990-01-01

    These are Proceedings of the Third Nordic Symposium on Computer Simulation in Physics, Chemistry, Biology, and Mathematics, held August 25-26, 1989, at Lahti (Finland). The Symposium belongs to an annual series of Meetings, the first one of which was arranged in 1987 at Lund (Sweden) and the second one in 1988 at Kolle-Kolle near Copenhagen (Denmark). Although these Symposia have thus far been essentially Nordic events, their international character has increased significantly; the trend is vividly reflected through contributions in the present Topical Issue. The interdisciplinary nature of Computational Science is central to the activity; this fundamental aspect is also responsible, in an essential way, for its rapidly increasing impact. Crucially important to a wide spectrum of superficially disparate fields is the common need for extensive - and often quite demanding - computational modelling. For such theoretical models, no closed-form (analytical) solutions are available or they would be extremely difficult to find; hence one must rather resort to the Art of performing computational investigations. Among the unifying features in the computational research are the methods of simulation employed; methods which frequently are quite closely related with each other even for faculties of science that are quite unrelated. Computer simulation in Natural Sciences is presently apprehended as a discipline on its own right, occupying a broad region somewhere between the experimental and theoretical methods, but also partially overlapping with and complementing them. - Whichever its proper definition may be, the computational approach serves as a novel and an extremely versatile tool with which one can equally well perform "pure" experimental modelling and conduct "computational theory". Computational studies that have earlier been made possible only through supercomputers have opened unexpected, as well as exciting, novel frontiers equally in mathematics (e.g., fractals

  20. Correlating Multimodal Physical Sensor Information with Biological Analysis in Ultra Endurance Cycling

    Directory of Open Access Journals (Sweden)

    Giles D.Warrington

    2010-07-01

    Full Text Available The sporting domain has traditionally been used as a testing ground for new technologies which subsequently make their way into the public domain. This includes sensors. In this article a range of physical and biological sensors deployed in a 64 hour ultra-endurance non-stop cycling race are described. A novel algorithm to estimate the energy expenditure while cycling and resting during the event are outlined. Initial analysis in this noisy domain of “sensors in the field” are very encouraging and represent a first with respect to cycling.

  1. Influence of physical and chemical factors on biological leaching process of copper from printed circuit boards

    Directory of Open Access Journals (Sweden)

    J. Willner

    2013-04-01

    Full Text Available The article presents the results of the research regarding the biological leaching of this metal from electronic wastes components in the form of printed circuit boards. The purpose of the study was to evaluate the influence of some physical and chemical factors (e.g. pH, oxidation-reduction potential on bioleaching process and efficiency of copper transfer from solid phase into solution. Bioleaching experiments were carried out with pure cultures of Acidithiobacillus ferrooxidans. The obtained results were discussed.

  2. Dynamics and thermodynamics in hierarchically organized systems applications in physics, biology and economics

    CERN Document Server

    Auger, P

    2013-01-01

    One of the most fundamental and efficient ways of conceptualizing complex systems is to organize them hierarchically. A hierarchically organized system is represented by a network of interconnected subsystems, each of which has its own network of subsystems, and so on, until some elementary subsystems are reached that are not further decomposed. This original and important book proposes a general mathematical theory of a hierarchical system and shows how it can be applied to very different topics such as physics (Hamiltonian systems), biology (coupling the molecular and the cellular levels), e

  3. Estimating Escherichia coli loads in streams based on various physical, chemical, and biological factors

    Science.gov (United States)

    Dwivedi, Dipankar; Mohanty, Binayak P.; Lesikar, Bruce J.

    2013-05-01

    Microbes have been identified as a major contaminant of water resources. Escherichia coli is a commonly used indicator organism. It is well recognized that the fate of E. coli in surface water systems is governed by multiple physical, chemical, and biological factors. The aim of this work is to provide insight into the physical, chemical, and biological factors along with their interactions that are critical in the estimation of E. coli loads in surface streams. There are various models to predict E. coli loads in streams, but they tend to be system- or site-specific or overly complex without enhancing our understanding of these factors. Hence, based on available data, a Bayesian neural network (BNN) is presented for estimating E. coli loads based on physical, chemical, and biological factors in streams. The BNN has the dual advantage of overcoming the absence of quality data (with regard to consistency in data) and determination of mechanistic model parameters by employing a probabilistic framework. This study evaluates whether the BNN model can be an effective alternative tool to mechanistic models for E. coli load estimation in streams. For this purpose, a comparison with a traditional model (load estimator (LOADEST), U.S. Geological Survey) is conducted. The models are compared for estimated E. coli loads based on available water quality data in Plum Creek, Texas. All the model efficiency measures suggest that overall E. coli load estimations by the BNN model are better than the E. coli load estimations by the LOADEST model on all the three occasions (threefold cross validation). Thirteen factors were used for estimating E. coli loads with the exhaustive feature selection technique, which indicated that 6 of 13 factors are important for estimating E. coli loads. Physical factors included temperature and dissolved oxygen; chemical factors include phosphate and ammonia; and biological factors include suspended solids and chlorophyll. The results highlight that

  4. Evaluation of biological, physical and chemical properties of mineral trioxide aggregate mixed with 4-META/MMA-TBB

    Directory of Open Access Journals (Sweden)

    Rudra Kaul

    2013-01-01

    Full Text Available Aim: To evaluate the change in physical, chemical and biological properties when mineral trioxide aggregate (MTA is mixed with a resin 4-methacryloxyethyl trimellitate anhydride (4-META/methyl methacrylate-tri-n-butyl-borane (MMA-TBB. Materials and Methods: For biological evaluation MTA was inoculated in Wistar rat′s subcutaneous tissue and peripheral tissue response was checked after 72 h, 7 days, 15 days and 30 days. Setting time was evaluated using Gillmore needle. The Ca++ release at the end of 24 h was checked using ethylenediaminetetraacetic acid titration method. For all the trials MTA mixed with water was kept as a control and the ratio of MTA with resin was 1:1 by weight. Results: The biological reaction was verified by two observers and their readings were matched using kappa test and there was an excellent relevance. There was no significant difference in the tissue reaction at the end of 30 days where both the groups seemed to show healing. Setting time of MTA with 4-META/MMA-TBB was coming to a mean of 26 min (approx., which is almost 6 times lesser than that of MTA with water. After applying t test, the difference in Ca++ release was found significant (P = 0.00, with mean of 0.044 and 0.031 mol/L of MTA with water and MTA with 4-META/MMA-TBB respectively. Conclusion: Under the parameters of this study, this new experimental cement has better handling, physical and chemical properties. Even its subcutaneous tissue reaction is comparable to MTA mixed with water.

  5. Physical, chemical, and biological data collected in Mobile Bay, Alabama in May 1989-December 1999 (NODC Accession 0116496)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains physical, chemical, and biological data collected during ten years of near-monthly shipboard surveys carried out in Mobile Bay between May...

  6. Relationship between psychological and biological factors and physical activity and exercise behaviour in Filipino students

    OpenAIRE

    Polman, Remco; Pieter, Willy; Luigi T. Bercades; Ntoumanis, Nikos

    2004-01-01

    The aim of the present study was threefold. Firstly, it investigated whether a general measure or specific measure of motivational orientation was better in describing the relationship between motivation and exercise behaviour. Secondly, it examined the relationship between the four most popular indirect methods of body composition assessment and physical activity and exercise patterns. Thirdly, the interaction between motivation and body composition on physical activity and exercise behaviou...

  7. Nature's longest threads new frontiers in the mathematics and physics of information in biology

    CERN Document Server

    Sreekantan, B V

    2014-01-01

    Organisms endowed with life show a sense of awareness, interacting with and learning from the universe in and around them. Each level of interaction involves transfer of information of various kinds, and at different levels. Each thread of information is interlinked with the other, and woven together, these constitute the universe — both the internal self and the external world — as we perceive it. They are, figuratively speaking, Nature's longest threads. This volume reports inter-disciplinary research and views on information and its transfer at different levels of organization by reputed scientists working on the frontier areas of science. It is a frontier where physics, mathematics and biology merge seamlessly, binding together specialized streams such as quantum mechanics, dynamical systems theory, and mathematics. The topics would interest a broad cross-section of researchers in life sciences, physics, cognition, neuroscience, mathematics and computer science, as well as interested amateurs, familia...

  8. Physical descriptions of the bacterial nucleoid at large scales, and their biological implications

    CERN Document Server

    Benza, Vincenzo G; Dorfman, Kevin D; Scolari, Vittore F; Bromek, Krystyna; Cicuta, Pietro; Lagomarsino, Marco Cosentino

    2012-01-01

    Recent experimental and theoretical approaches have attempted to quantify the physical organization (compaction and geometry) of the bacterial chromosome with its complement of proteins (the nucleoid). The genomic DNA exists in a complex and dynamic protein-rich state, which is highly organised at various length scales. This has implications on modulating (when not enabling) the core biological processes of replication, transcription, segregation. We overview the progress in this area, driven in the last few years by new scientific ideas and new interdisciplinary experimental techniques, ranging from high space- and time-resolution microscopy to high-throughput genomics employing sequencing to map different aspects of the nucleoid-related interactome. The aim of this review is to present the wide spectrum of experimental and theoretical findings coherently, from a physics viewpoint. We also discuss some attempts of interpretation that unify different results, highlighting the role that statistical and soft co...

  9. Thiosemicarbazones: preparation methods, synthetic applications and biological importance

    International Nuclear Information System (INIS)

    Thiosemicarbazones are a class of compounds known by their chemical and biological properties, such as antitumor, antibacterial, antiviral and antiprotozoal activity. Their ability to form chelates with metals has great importance in their biological activities. Their synthesis is very simple, versatile and clean, usually giving high yields. They are largely employed as intermediates, in the synthesis of others compounds. This article is a survey of some of these characteristics showing their great importance to organic and medicinal chemistry. (author)

  10. Computational Systems Biology in Cancer: Modeling Methods and Applications

    OpenAIRE

    Wayne Materi; Wishart, David S.

    2007-01-01

    In recent years it has become clear that carcinogenesis is a complex process, both at the molecular and cellular levels. Understanding the origins, growth and spread of cancer, therefore requires an integrated or system-wide approach. Computational systems biology is an emerging sub-discipline in systems biology that utilizes the wealth of data from genomic, proteomic and metabolomic studies to build computer simulations of intra and intercellular processes. Several useful descriptive and pre...

  11. Radiation damage and repair in cells and cell components. Part 2. Physical radiations and biological significance. Final report

    International Nuclear Information System (INIS)

    The report comprises a teaching text, encompassing all physical radiations likely to be of biological interest, and the relevant biological effects and their significance. Topics include human radiobiology, delayed effects, radiation absorption in organisms, aqueous radiation chemistry, cell radiobiology, mutagenesis, and photobiology

  12. Stories of staying and leaving: A mixed methods analysis of biology undergraduate choice, persistence, and departure

    Science.gov (United States)

    Lang, Sarah Adrienne

    Using a sequential, explanatory mixed methods design, this dissertation study compared students who persist in the biology major (persisters) with students who leave the biology major (switchers) in terms of how their pre-college experiences, college biology experiences, and biology performance figured into their choice of biology and their persistence in or departure from the biology major. This study combined (1) quantitative comparisons of biology persisters and switchers via a questionnaire developed for the study and survival analysis of a larger population of biology freshmen with (2) qualitative comparison of biology switchers and persisters via semi-structured life story interviews and homogenous focus groups. 319 students (207 persisters and 112 switchers) participated in the questionnaire and 36 students (20 persisters and 16 switchers) participated in life story and focus group interviews. All participants were undergraduates who entered The University of Texas at Austin as biology freshmen in the fall semesters of 2000 through 2004. Findings of this study suggest: (1) Regardless of eventual major, biology students enter college with generally the same suite of experiences, sources of personal encouragement, and reasons for choosing the biology major; (2) Despite the fact that they have also had poor experiences in the major, biology persisters do not actively decide to stay in the biology major; they simply do not leave; (3) Based upon survival analysis, biology students are most at-risk of leaving the biology major during the first two years of college and if they are African-American or Latino, women, or seeking a Bachelor of Arts degree (rather than a Bachelor of Science); (4) Biology switchers do not leave biology due to preference for other disciplines; they leave due to difficulties or dissatisfaction with aspects of the biology major, including their courses, faculty, and peers; (5) Biology performance has a differential effect on persistence in

  13. Highly cited German research contributions to the fields of radiation oncology, biology, and physics. Focus on collaboration and diversity

    International Nuclear Information System (INIS)

    Background and purpose: Tight budgets and increasing competition for research funding pose challenges for highly specialized medical disciplines such as radiation oncology. Therefore, a systematic review was performed of successfully completed research that had a high impact on clinical practice. These data might be helpful when preparing new projects. Methods: Different measures of impact, visibility, and quality of published research are available, each with its own pros and cons. For this study, the article citation rate was chosen (minimum 15 citations per year on average). Highly cited German contributions to the fields of radiation oncology, biology, and physics (published between 1990 and 2010) were identified from the Scopus database. Results: Between 1990 and 2010, 106 articles published in 44 scientific journals met the citation requirement. The median average of yearly citations was 21 (maximum 167, minimum 15). All articles with ≥ 40 citations per year were published between 2003 and 2009, consistent with the assumption that the citation rate gradually increases for up to 2 years after publication. Most citations per year were recorded for meta-analyses and randomized phase III trials, which typically were performed by collaborative groups. Conclusion: A large variety of clinical radiotherapy, biology, and physics topics achieved high numbers of citations. However, areas such as quality of life and side effects, palliative radiotherapy, and radiotherapy for nonmalignant disorders were underrepresented. Efforts to increase their visibility might be warranted. (orig.)

  14. An introduction to computer simulation methods applications to physical systems

    CERN Document Server

    Gould, Harvey; Christian, Wolfgang

    2007-01-01

    Now in its third edition, this book teaches physical concepts using computer simulations. The text incorporates object-oriented programming techniques and encourages readers to develop good programming habits in the context of doing physics. Designed for readers at all levels , An Introduction to Computer Simulation Methods uses Java, currently the most popular programming language. Introduction, Tools for Doing Simulations, Simulating Particle Motion, Oscillatory Systems, Few-Body Problems: The Motion of the Planets, The Chaotic Motion of Dynamical Systems, Random Processes, The Dynamics of Many Particle Systems, Normal Modes and Waves, Electrodynamics, Numerical and Monte Carlo Methods, Percolation, Fractals and Kinetic Growth Models, Complex Systems, Monte Carlo Simulations of Thermal Systems, Quantum Systems, Visualization and Rigid Body Dynamics, Seeing in Special and General Relativity, Epilogue: The Unity of Physics For all readers interested in developing programming habits in the context of doing phy...

  15. Macromolecular crowding: chemistry and physics meet biology (Ascona, Switzerland, 10-14 June 2012)

    Science.gov (United States)

    Foffi, G.; Pastore, A.; Piazza, F.; Temussi, P. A.

    2013-08-01

    held in Ascona from 10 to 14 June 2012. In the unique scenario of the Maggiore lake and absorbed in the magic atmosphere of the Centro Stefano Franscini (CSF) at Monte Verità, we enjoyed three-and-a-half days of intense and inspiring activity, where not only many of the most prominent scientists working on macromolecular crowding, but also experts in closely related fields such as colloids and soft matter presented their work. The meeting was intended and has been organized to bring theoreticians and experimentalists together in the attempt to promote an active dialogue. Moreover, we wanted different disciplines to be represented, notably physics and chemistry, besides biology, as cross-fertilization is proving an increasingly fundamental source of inspiration and advancement. This issue of Physical Biology (PB) features a selection of the oral contributions presented at the conference, expanded in the form of research or review articles. PB, one of the scientific journals of the Institute of Physics (IOP), is one of the most dynamic and lively forums active at the interface between biology on one side, and physics and mathematics on the other. As its mission is stated by IOP, PB 'focuses on research in which physics-based approaches lead to new insights into biological systems at all scales of space and time, and all levels of complexity'. For these reasons, and also in view of its high reputation and broad readership, PB appears to be the ideal place for disseminating the thriving pieces of research presented at the conference. We are extremely grateful to PB and its kind and efficient editorial staff who helped make this issue a great scientific follow-up to the conference. The opening lecture of the conference, the first of four day-opening keynote lectures, was given by Allen P Minton from NIH (USA), possibly the most influential among the pioneers in the field. He provided a lucid and well-thought-out overview of the concept of macromolecular crowding through an

  16. Macromolecular crowding: chemistry and physics meet biology (Ascona, Switzerland, 10-14 June 2012).

    Science.gov (United States)

    Foffi, G; Pastore, A; Piazza, F; Temussi, P A

    2013-08-01

    conference held in Ascona from 10 to 14 June 2012. In the unique scenario of the Maggiore lake and absorbed in the magic atmosphere of the Centro Stefano Franscini (CSF) at Monte Verità, we enjoyed three-and-a-half days of intense and inspiring activity, where not only many of the most prominent scientists working on macromolecular crowding, but also experts in closely related fields such as colloids and soft matter presented their work. The meeting was intended and has been organized to bring theoreticians and experimentalists together in the attempt to promote an active dialogue. Moreover, we wanted different disciplines to be represented, notably physics and chemistry, besides biology, as cross-fertilization is proving an increasingly fundamental source of inspiration and advancement. This issue of Physical Biology (PB) features a selection of the oral contributions presented at the conference, expanded in the form of research or review articles. PB, one of the scientific journals of the Institute of Physics (IOP), is one of the most dynamic and lively forums active at the interface between biology on one side, and physics and mathematics on the other. As its mission is stated by IOP, PB 'focuses on research in which physics-based approaches lead to new insights into biological systems at all scales of space and time, and all levels of complexity'. For these reasons, and also in view of its high reputation and broad readership, PB appears to be the ideal place for disseminating the thriving pieces of research presented at the conference. We are extremely grateful to PB and its kind and efficient editorial staff who helped make this issue a great scientific follow-up to the conference. The opening lecture of the conference, the first of four day-opening keynote lectures, was given by Allen P Minton from NIH (USA), possibly the most influential among the pioneers in the field. He provided a lucid and well-thought-out overview of the concept of macromolecular crowding

  17. Introduction on microbiological and biological methods and their possible combination with other analytical techniques for the detection of irradiated food

    International Nuclear Information System (INIS)

    Food irradiation is a physical method of processing and preserving food. One of the main purposes of the application of this technology to food is to obtain specific biological effects on the treated foodstuff. Typical examples of these treatment effects are listed in the article. A whole range of techniques is at disposal of the analyst to assure the Quality Control (QC) of various foodstuffs. They are based on microbiological, organoleptical, chemical, biochemical, immunological and/or physical methods. In the case of irradiation preserved food the opinion of the writer is that very often only a combination of analytical methods can solve the problem of detection of irradiated foodstuffs and in particular in most cases this combination could be formed by a biological or microbiological method + a chemical or physical one. The meaning of these combination of techniques is manifold. Combining the advantages of a rapid screening method with those of a more refined, reliable, even if more time consuming one; offering the possibility to carry out the analysis for the control of irradiated foodstuffs to different kinds of food control laboratories, often equipped in a different way, are some of the most evident advantages. These methods are briefly explained. At present, none method seems promising for the quantitative determination of the irradiation dose. Moreover, some of the proposed methods can only give a good presumption of the irradiation treatment applied to particular foodstuffs. (18 refs)

  18. Office of Biological and Physical Research: Overview Transitioning to the Vision for Space Exploration

    Science.gov (United States)

    Crouch, Roger

    2004-01-01

    Viewgraphs on NASA's transition to its vision for space exploration is presented. The topics include: 1) Strategic Directives Guiding the Human Support Technology Program; 2) Progressive Capabilities; 3) A Journey to Inspire, Innovate, and Discover; 4) Risk Mitigation Status Technology Readiness Level (TRL) and Countermeasures Readiness Level (CRL); 5) Biological And Physical Research Enterprise Aligning With The Vision For U.S. Space Exploration; 6) Critical Path Roadmap Reference Missions; 7) Rating Risks; 8) Current Critical Path Roadmap (Draft) Rating Risks: Human Health; 9) Current Critical Path Roadmap (Draft) Rating Risks: System Performance/Efficiency; 10) Biological And Physical Research Enterprise Efforts to Align With Vision For U.S. Space Exploration; 11) Aligning with the Vision: Exploration Research Areas of Emphasis; 12) Code U Efforts To Align With The Vision For U.S. Space Exploration; 13) Types of Critical Path Roadmap Risks; and 14) ISS Human Support Systems Research, Development, and Demonstration. A summary discussing the vision for U.S. space exploration is also provided.

  19. Darwin's legacy: why biology is not physics, or why evolution has not become a common sense.

    Science.gov (United States)

    Singh, Rama S

    2011-10-01

    Cosmology and evolution together have enabled us to look deep into the past and comprehend evolution-from the big bang to the cosmos, from molecules to humans. Here, I compare the nature of theories in biology and physics and ask why physical theories get accepted by the public without necessarily comprehending them but biological theories do not. Darwin's theory of natural selection, utterly simple in its premises but profound in its consequences, is not accepted widely. Organized religions, and creationists in particularly, have been the major critic of evolution, but not all opposition to evolution comes from organized religions. A great many people, between evolutionary biologists on one hand and creationists on the other, many academics included, who may not be logically opposed to evolution nevertheless do not accept it. This is because the process of and the evidence for evolution are invisible to a nonspecialist, or the theory may look too simple to explain complex traits to some, or because people compare evolution against God and find evolutionary explanations threatening to their beliefs. Considering how evolution affects our lives, including health and the environment to give just two examples, a basic course in evolution should become a required component of all our college and university educational systems. PMID:21942430

  20. An entrepreneurial physics method and its experimental test

    Science.gov (United States)

    Brown, Robert

    2012-02-01

    As faculty in a master's program for entrepreneurial physics and in an applied physics PhD program, I have advised upwards of 40 master and doctoral theses in industrial physics. I have been closely involved with four robust start-up manufacturing companies focused on physics high-technology and I have spent 30 years collaborating with industrial physicists on research and development. Thus I am in a position to reflect on many articles and advice columns centered on entrepreneurship. What about the goals, strategies, resources, skills, and the 10,000 hours needed to be an entrepreneur? What about business plans, partners, financing, patents, networking, salesmanship and regulatory affairs? What about learning new technology, how to solve problems and, in fact, learning innovation itself? At this point, I have my own method to propose to physicists in academia for incorporating entrepreneurship into their research lives. With this method, we do not start with a major invention or discovery, or even with a search for one. The method is based on the training we have, and the teaching we do (even quantum electrodynamics!), as physicists. It is based on the networking we build by 1) providing courses of continuing education for people working in industry and 2) through our undergraduate as well as graduate students who have gone on to work in industry. In fact, if we were to be limited to two words to describe the method, they are ``former students.'' Data from local and international medical imaging manufacturing industry are presented.

  1. Physical methods for detection of irradiated foods: introduction

    International Nuclear Information System (INIS)

    These are the main physical methods to be explored in this session though of course any new ideas will be welcomed. It could be said that for solid materials the solution is well advanced with ESR, thermoluminescence, and possibly photo-luminescence. For wet materials, the problems are much greater and it has to be admitted that there is no panacea

  2. Physics must join with biology in better assessing risk from low-dose irradiation

    International Nuclear Information System (INIS)

    This review summarises the complex response of mammalian cells and tissues to low doses of ionising radiation. This thesis encompasses induction of DNA damage, and adaptive protection against both renewed damage and against propagation of damage from the basic level of biological organisation to the clinical expression of detriment. The induction of DNA damage at low radiation doses apparently is proportional to absorbed dose at the physical/chemical level. However, any propagation of such damage to higher levels of biological organisation inherently follows a sigmoid function. Moreover, low-dose-induced inhibition of damage propagation is not linear, but instead follows a dose-effect function typical for adaptive protection, after an initial rapid rise it disappears at doses higher than ∼0.1-0.2 Gy to cells. The particular biological response duality at low radiation doses precludes the validity of the linear-no-threshold hypothesis in the attempt to relate absorbed dose to cancer. In fact, theory and observation support not only a lower cancer incidence than expected from the linear-no-threshold hypothesis, but also a reduction of spontaneously occurring cancer, a hormetic response, in the healthy individual. (authors)

  3. Monte Carlo methods and applications in nuclear physics

    International Nuclear Information System (INIS)

    Monte Carlo methods for studying few- and many-body quantum systems are introduced, with special emphasis given to their applications in nuclear physics. Variational and Green's function Monte Carlo methods are presented in some detail. The status of calculations of light nuclei is reviewed, including discussions of the three-nucleon-interaction, charge and magnetic form factors, the coulomb sum rule, and studies of low-energy radiative transitions. 58 refs., 12 figs

  4. Dosing method of physical activity in aerobics classes for students

    OpenAIRE

    Beliak Yu. I.; Zinchenko N.M.

    2014-01-01

    Purpose : reasons for the method of dosing of physical activity in aerobics classes for students. The basis of the method is the evaluation of the metabolic cost of funds used in them. Material : experiment involved the assessment of the pulse response of students to load complexes classical and step aerobics (n = 47, age 20-23 years). In complexes used various factors regulating the intensity: perform combinations of basic steps, involvement of movements with his hands, holding in hands dumb...

  5. Tritium in the Physical and Biological Sciences. V. 1. Proceedings of a Symposium

    International Nuclear Information System (INIS)

    The use of tritium for research in physics, chemistry, biology and hydrology has in recent years become increasingly important. It was for this reason that the first international conference to discuss the progress of new developments was organized by the IAEA in conjunction with the Joint Commission on Applied Radioactivity and held from 3-10 May 1961, in Vienna. The first five sessions of the Symposium were devoted to the use of tritium in hydrology, physics and chemistry. Special emphasis was laid on the role of tritium as a tracer in hydrology, especially in the study of water movement. The establishment and improvement of counting and detection techniques to facilitate the application of tritium as a tracer was another aspect discussed in this part of the proceedings. Papers were read on the preparation of tritiated compounds and it was generally agreed that further clarification of the mechanism of various techniques, and of the Wilzbach gas exposure technique in particular, would lead to further developments in the synthesis of a number of tritium compounds important in biology. Other papers were concerned with tritium applications to studies of the mechanism of some chemical reactions together with the effects of tritium isotopes. During the second part of the Symposium the biological applications of tritium and tritiated compounds were discussed. These included general problems connected with the biological uses of tritium and the radiation effects of tritium on living organisms such as viruses, bacteria and cancer cells. The value of tritium in biological studies became apparent because of the ease with which a large number of metabolically active compounds such as hormones, vitamins and other important constituents in the body can be labelled with tritium. Tritium is also a weak beta-emitter and autoradiographie s of tissues and single cells containing tritium-labelled compounds allow an excellent localization of the tracer. The Symposium was attended by

  6. Progress report, Biology and Health Physics Division, January 1 to March 31, 1978

    International Nuclear Information System (INIS)

    Progress of work in Biology and Health Physics Division is reported for first quarter 1978. Measurements of liquid and plastic scintillator responses over a wide range of gamma-ray energies and calculations of the shape of the Compton electron distribution have been made for different scintillator sizes. Other work performed in health physics included determination of errors involved in accurate determination of dose-equivalents resulting from tritium ingestion, and development of radiation monitors and techniques for using them to best advantage. A wide range of environmental studies were underway during the quarter, notably 14C/12C ratio measurement using an accelerator-spectrometer and contiuing studies of the beneficial uses of thermal effluents. Development of computer linkage techniques for medical records continued. Practical applications of the approach include linkage of personal exposure histories with death records pertaining to the exposed individuals. Work in the Biology Branch has continued to focus upon the effects of radiation on a variety of living organisms, ranging from bacterial viruses to humans. The principal sensitive target for long-term biological effects of radiation on all living organisms is DNA. The chemical nature of the damage caused in DNA by radiation and the response of cells to this damage is being studied by a variety of biochemical and genetic techniques. A review of literature on the causes of cancer in humans has continued. If effects are linearly related to total dose, as is normally assumed for purposes of radiation protection, then the total number of fatal cancers predicted to arise from the use of nuclear power in the future should be about 100 times less than the number induced by urban air pollution resulting from the combustion of coal and oil to produce the same amount of electricity. (OST)

  7. XXXIV Bialowieza Workshop on Geometric Methods in Physics

    CERN Document Server

    Ali, S; Bieliavsky, Pierre; Odzijewicz, Anatol; Schlichenmaier, Martin; Voronov, Theodore

    2016-01-01

    This book features a selection of articles based on the XXXIV Białowieża Workshop on Geometric Methods in Physics, 2015. The articles presented are mathematically rigorous, include important physical implications and address the application of geometry in classical and quantum physics. Special attention deserves the session devoted to discussions of Gerard Emch's most important and lasting achievements in mathematical physics. The Białowieża workshops are among the most important meetings in the field and gather participants from mathematics and physics alike. Despite their long tradition, the Workshops remain at the cutting edge of ongoing research. For the past several years, the Białowieża Workshop has been followed by a School on Geometry and Physics, where advanced lectures for graduate students and young researchers are presented. The unique atmosphere of the Workshop and School is enhanced by the venue, framed by the natural beauty of the Białowieża forest in eastern Poland.

  8. The effect of teaching methods on cognitive achievement, retention, and attitude among in biology studying

    OpenAIRE

    Snezana Stavrova Veselinovskaa

    2011-01-01

    The purpose of this paper is to determine the effects of usage of sequential teaching method on the academic achievement and retention level of students. Three student groups of biology students in University “Goce Delcev”, Faculty of Natural and Technical Sciences, Institute of Biology, - Stip, R. Macedonia were offered a topic on general characteristics of Proteins: Their Biological Functions and Primary Structure with different sequences of 3 teaching methods. The teaching methods were Lab...

  9. Levels of Biological Diversity: a Spatial Approach to Assessment Methods

    Directory of Open Access Journals (Sweden)

    ALEXANDRU-IONUŢ PETRIŞOR

    2008-01-01

    Full Text Available Biological diversity, interpreted as a variety of natural and man-dominated biological and ecological systems, plays an important role in assuring their stability and can be interpreted at different spatial scales, based on the hierarchical level of the system (biocoenose/ ecosystem, biome/complex of ecosystem, biosphere/ecosphere. Literature distinguishes six levels of biodiversity, namely alpha, beta, gamma, delta, epsilon, and omega. The current paper lists methodologies appropriate for assessing diversity at each of these levels, with a particular focus on regional diversity (gamma, delta, and epsilon diversities, i.e. CORINE land cover classification and the biogeographical regions of the European Union.

  10. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1992--November 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood ``biological fingerprint`` of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  11. A Comparative Study of Methods To Validate Formaldehyde Decontamination of Biological Safety Cabinets

    OpenAIRE

    Munro, Kerry; Lanser, Janice; Flower, Robert

    1999-01-01

    Methods of validation of formaldehyde decontamination of biological safety cabinets were compared. Decontamination of metal strips inoculated with Mycobacterium bovis, poliovirus, or Bacillus spp. spores was compared with the results obtained with three biological indicators. Conditions for successful decontamination, particularly relative humidity, were defined. The Attest 1291 biological indicator was the only biological indicator which was an aid in the detection of gross decontamination f...

  12. Decomposing the effects of ocean warming on chlorophyll a concentrations into physically and biologically driven contributions

    International Nuclear Information System (INIS)

    Recently compiled observational data suggest a substantial decline in the global median chlorophyll a concentration over the 20th century, a trend that appears to be linked to ocean warming. Several modelling studies have considered changes in the ocean’s physical structure as a possible cause, while experimental work supports a biological mechanism, namely an observed increase in zooplankton grazing rate that outpaces phytoplankton production at higher temperatures. Here, we present transient simulations derived from a coupled ocean general circulation and carbon cycle model forced by atmospheric fields under unabated anthropogenic global warming (IPCC SRES A1FI scenario). The simulations account for both physical and biological mechanisms, and can reproduce about one quarter of the observed chlorophyll a decline during the 20th century, when using realistically parameterized temperature sensitivity of zooplankton metabolism (Q10 between 2 and 4) and phytoplankton growth (Q10 ∼ 1.9). Therefore, we have employed and re-calibrated the standard ecosystem model which assumes a lower temperature sensitivity of zooplankton grazing (Q10 = 1.1049) by re-scaling phytoplankton growth rates and zooplankton grazing rates. Our model projects a global chlorophyll a decline of >50% by the end of the 21st century. While phytoplankton abundance and chlorophyll a experience pronounced negative effects, primary production and zooplankton concentrations are less sensitive to ocean warming. Although changes in physical structure play an important role, much of the simulated change in chlorophyll a and productivity is related to the uneven temperature sensitivity of the marine ecosystem. (letter)

  13. Applications of Symmetry Methods to the Theory of Plasma Physics

    Directory of Open Access Journals (Sweden)

    Giampaolo Cicogna

    2006-02-01

    Full Text Available The theory of plasma physics offers a number of nontrivial examples of partial differential equations, which can be successfully treated with symmetry methods. We propose three different examples which may illustrate the reciprocal advantage of this "interaction" between plasma physics and symmetry techniques. The examples include, in particular, the complete symmetry analysis of system of two PDE's, with the determination of some conditional and partial symmetries, the construction of group-invariant solutions, and the symmetry classification of a nonlinear PDE.

  14. Fundamentals of many-body physics. Principles and methods

    International Nuclear Information System (INIS)

    This textbook addresses the special physics of many-particle systems, especially those dominated by correlation effects. It develops modern methods to treat such systems and demonstrates their application through numerous appropriate exercises, mainly from the field of solid state physics. The book is written in a tutorial style appropriate for those who want to learn many-body theory and eventually to use this to do research work in this field. The exercises, together with full solutions for evaluating one's performance, help to deepen understanding of the main aspects of many-particle systems. (orig.)

  15. Computational methods in high-energy-density physics

    International Nuclear Information System (INIS)

    High-Energy-Density (HED) Physics involves experimental, theoretical and computational research in high pressure equation of state (EOS) of matter, opacity of materials in the plasma state, neutral and charged particle cross-section libraries, database for high explosives (HE), shock wave propagation, radiation and explosive driven hydrodynamics, particle transport theory, and modelling of complex experimental systems for inertial confinement fusion. These fields are intimately related to nuclear weapons research as well. Some of the typical computational methods used in HED physics are briefly covered in this talk. (author)

  16. Applications of physical methods in high-frequency futures markets

    OpenAIRE

    Bartolozzi, M.; Mellen, C.; Chan, F; Oliver, David J.; Di Matteo, T.; Aste, Tomaso

    2007-01-01

    In the present work we demonstrate the application of different physical methods to high-frequency or tick-by-tick financial time series data. In particular, we calculate the Hurst exponent and inverse statistics for the price time series taken from a range of futures indices. Additionally, we show that in a limit order book the relaxation times of an imbalanced book state with more demand or supply can be described by stretched exponential laws analogous to those seen in many physical systems.

  17. Stable isotope methods in biological and ecological studies of arthropods

    NARCIS (Netherlands)

    Hood-Nowotny, R.C.; Knols, B.G.J.

    2007-01-01

    This is an eclectic review and analysis of contemporary and promising stable isotope methodologies to study the biology and ecology of arthropods. It is augmented with literature from other disciplines, indicative of the potential for knowledge transfer. It is demonstrated that stable isotopes can b

  18. Using Collision Cones to Asses Biological Deconiction Methods

    Science.gov (United States)

    Brace, Natalie

    For autonomous vehicles to navigate the world as efficiently and effectively as biological species, improvements are needed in terms of control strategies and estimation algorithms. Reactive collision avoidance is one specific area where biological systems outperform engineered algorithms. To better understand the discrepancy between engineered and biological systems, a collision avoidance algorithm was applied to frames of trajectory data from three biological species (Myotis velifer, Hirundo rustica, and Danio aequipinnatus). The algorithm uses information that can be sensed through visual cues (relative position and velocity) to define collision cones which are used to determine if agents are on a collision course and if so, to find a safe velocity that requires minimal deviation from the original velocity for each individual agent. Two- and three-dimensional versions of the algorithm with constant speed and maximum speed velocity requirements were considered. The obstacles provided to the algorithm were determined by the sensing range in terms of either metric or topological distance. The calculated velocities showed good correlation with observed velocities over the range of sensing parameters, indicating that the algorithm is a good basis for comparison and could potentially be improved with further study.

  19. Thin film composition with biological substance and method of making

    International Nuclear Information System (INIS)

    The invention provides a thin-film composition comprising an underlying substrate of a first material including a plurality of attachment sites; a plurality of functional groups chemically attached to the attachment sites of the underlying substrate; and a thin film of a second material deposited onto the attachment sites of the underlying substrate, and a biologically active substance deposited with the thin-film. Preferably the functional groups are attached to a self assembling monolayer attached to the underlying substrate. Preferred functional groups attached to the underlying substrate are chosen from the group consisting of carboxylates, sulfonates, phosphates, optionally substituted, linear or cyclo, alkyl, alkene, alkyne, aryl, alkylaryl, amine, hydroxyl, thiol, silyl, phosphoryl, cyano, metallocenyl, carbonyl, and polyphosphate. Preferred materials for the underlying substrate are selected from the group consisting of a metal, a metal alloy, a plastic, a polymer, a proteic film, a membrane, a glass or a ceramic. The second material is selected from the group consisting of inorganic crystalline structures, inorganic amorphous structures, organic crystalline structures, and organic amorphous structures. Preferred second materials are phosphates, especially calcium phosphates and most particularly calcium apatite. The biologically active molecule is a protein, peptide, DNA segment, RNA segment, nucleotide, polynucleotide, nucleoside, antibiotic, antimicrobial, radioisotope, chelated radioisotope, chelated metal, metal salt, anti-inflammatory, steroid, nonsteroid anti-inflammatory, analgesic, antihistamine, receptor binding agent, or chemotherapeutic agent, or other biologically active material. Preferably the biologically active molecule is an osteogenic factor consisting of the compositions listed above

  20. Academic Training Lecture: Statistical Methods for Particle Physics

    CERN Multimedia

    PH Department

    2012-01-01

    2, 3, 4 and 5 April 2012 Academic Training Lecture  Regular Programme from 11:00 to 12:00 -  Bldg. 222-R-001 - Filtration Plant Statistical Methods for Particle Physics by Glen Cowan (Royal Holloway) The series of four lectures will introduce some of the important statistical methods used in Particle Physics, and should be particularly relevant to those involved in the analysis of LHC data. The lectures will include an introduction to statistical tests, parameter estimation, and the application of these tools to searches for new phenomena.  Both frequentist and Bayesian methods will be described, with particular emphasis on treatment of systematic uncertainties.  The lectures will also cover unfolding, that is, estimation of a distribution in binned form where the variable in question is subject to measurement errors.

  1. Biologically Based Methods for Control of Fumonisin-Producing Fusarium Species and Reduction of the Fumonisins

    Science.gov (United States)

    Alberts, Johanna F.; van Zyl, Willem H.; Gelderblom, Wentzel C. A.

    2016-01-01

    selected biologically based treatments, mild chemical and physical treatments could reduce fumonisin contamination effectively. In rural subsistence farming communities, simple, practical, and culturally acceptable hand-sorting, maize kernel washing, and dehulling intervention methods proved to be effective as a last line of defense for reducing fumonisin exposure. Biologically based methods for control of fumonisin-producing Fusarium spp. and decontamination of the fumonisins could have potential commercial application, while simple and practical intervention strategies could also impact positively on food safety and security, especially in rural populations reliant on maize as a dietary staple. PMID:27199904

  2. Biologically Based Methods for Control of Fumonisin-Producing Fusarium Species and Reduction of the Fumonisins.

    Science.gov (United States)

    Alberts, Johanna F; van Zyl, Willem H; Gelderblom, Wentzel C A

    2016-01-01

    selected biologically based treatments, mild chemical and physical treatments could reduce fumonisin contamination effectively. In rural subsistence farming communities, simple, practical, and culturally acceptable hand-sorting, maize kernel washing, and dehulling intervention methods proved to be effective as a last line of defense for reducing fumonisin exposure. Biologically based methods for control of fumonisin-producing Fusarium spp. and decontamination of the fumonisins could have potential commercial application, while simple and practical intervention strategies could also impact positively on food safety and security, especially in rural populations reliant on maize as a dietary staple. PMID:27199904

  3. Biologically Based Methods for Control of Fumonisin-producing Fusarium species and Reduction of the Fumonisins

    Directory of Open Access Journals (Sweden)

    Johanna Francina Alberts

    2016-04-01

    , together with selected biologically based treatments, mild chemical and physical treatments could reduce fumonisin contamination effectively. In rural subsistence farming communities, simple, practical and culturally acceptable hand-sorting, maize kernel washing and dehulling intervention methods proved to be effective as a last line of defence for reducing fumonisin exposure. Biologically based methods for control of fumonisin-producing Fusarium spp. and decontamination of the fumonisins could have potential commercial application, while simple and practical intervention strategies could also impact positively on food safety and security, especially in rural populations reliant on maize as a dietary staple.

  4. Environmental parameters of the Tennessee River in Alabama. 2: Physical, chemical, and biological parameters. [biological and chemical effects of thermal pollution from nuclear power plants on water quality

    Science.gov (United States)

    Rosing, L. M.

    1976-01-01

    Physical, chemical and biological water quality data from five sites in the Tennessee River, two in Guntersville Reservoir and three in Wheeler Reservoir were correlated with climatological data for three annual cycles. Two of the annual cycles are for the years prior to the Browns Ferry Nuclear Power Plant operations and one is for the first 14 months of Plant operations. A comparison of the results of the annual cycles indicates that two distinct physical conditions in the reservoirs occur, one during the warm months when the reservoirs are at capacity and one during the colder winter months when the reservoirs have been drawn-down for water storage during the rainy months and for weed control. The wide variations of physical and chemical parameters to which the biological organisms are subjected on an annual basis control the biological organisms and their population levels. A comparison of the parameters of the site below the Power plant indicates that the heated effluent from the plant operating with two of the three reactors has not had any effect on the organisms at this site. Recommendations given include the development of prediction mathematical models (statistical analysis) for the physical and chemical parameters under specific climatological conditions which affect biological organisms. Tabulated data of chemical analysis of water and organism populations studied is given.

  5. Protons at the speed of sound: Predicting specific biological signaling from physics

    Science.gov (United States)

    Fichtl, Bernhard; Shrivastava, Shamit; Schneider, Matthias F.

    2016-05-01

    Local changes in pH are known to significantly alter the state and activity of proteins and enzymes. pH variations induced by pulses propagating along soft interfaces (e.g. membranes) would therefore constitute an important pillar towards a physical mechanism of biological signaling. Here we investigate the pH-induced physical perturbation of a lipid interface and the physicochemical nature of the subsequent acoustic propagation. Pulses are stimulated by local acidification and propagate – in analogy to sound – at velocities controlled by the interface’s compressibility. With transient local pH changes of 0.6 directly observed at the interface and velocities up to 1.4 m/s this represents hitherto the fastest protonic communication observed. Furthermore simultaneously propagating mechanical and electrical changes in the lipid interface are detected, exposing the thermodynamic nature of these pulses. Finally, these pulses are excitable only beyond a threshold for protonation, determined by the pKa of the lipid head groups. This protonation-transition plus the existence of an enzymatic pH-optimum offer a physical basis for intra- and intercellular signaling via sound waves at interfaces, where not molecular structure and mechano-enyzmatic couplings, but interface thermodynamics and thermodynamic transitions are the origin of the observations.

  6. Biological effects and physical safety aspects of NMR imaging and in vivo spectroscopy

    International Nuclear Information System (INIS)

    An assessment is made of the biological effects and physical hazards of static and time-varying fields associated with the NMR devices that are being used for clinical imaging and in vivo spectroscopy. A summary is given of the current state of knowledge concerning the mechanisms of interaction and the bioeffects of these fields. Additional topics that are discussed include: (1) physical effects on pacemakers and metallic implants such as aneurysm clips, (2) human health studies related to the effects of exposure to nonionizing electromagnetic radiation, and (3) extant guidelines for limiting exposure of patients and medical personnel to the fields produced by NMR devices. On the basis of information available at the present time, it is concluded that the fields associated with the current generation of NMR devices do not pose a significant health risk in themselves. However, rigorous guidelines must be followed to avoid the physical interaction of these fields with metallic implants and medical electronic devices. 476 refs., 5 figs., 2 tabs

  7. Protons at the speed of sound: Predicting specific biological signaling from physics.

    Science.gov (United States)

    Fichtl, Bernhard; Shrivastava, Shamit; Schneider, Matthias F

    2016-01-01

    Local changes in pH are known to significantly alter the state and activity of proteins and enzymes. pH variations induced by pulses propagating along soft interfaces (e.g. membranes) would therefore constitute an important pillar towards a physical mechanism of biological signaling. Here we investigate the pH-induced physical perturbation of a lipid interface and the physicochemical nature of the subsequent acoustic propagation. Pulses are stimulated by local acidification and propagate - in analogy to sound - at velocities controlled by the interface's compressibility. With transient local pH changes of 0.6 directly observed at the interface and velocities up to 1.4 m/s this represents hitherto the fastest protonic communication observed. Furthermore simultaneously propagating mechanical and electrical changes in the lipid interface are detected, exposing the thermodynamic nature of these pulses. Finally, these pulses are excitable only beyond a threshold for protonation, determined by the pKa of the lipid head groups. This protonation-transition plus the existence of an enzymatic pH-optimum offer a physical basis for intra- and intercellular signaling via sound waves at interfaces, where not molecular structure and mechano-enyzmatic couplings, but interface thermodynamics and thermodynamic transitions are the origin of the observations. PMID:27216038

  8. Biological effects and physical safety aspects of NMR imaging and in vivo spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tenforde, T.S.; Budinger, T.F.

    1985-08-01

    An assessment is made of the biological effects and physical hazards of static and time-varying fields associated with the NMR devices that are being used for clinical imaging and in vivo spectroscopy. A summary is given of the current state of knowledge concerning the mechanisms of interaction and the bioeffects of these fields. Additional topics that are discussed include: (1) physical effects on pacemakers and metallic implants such as aneurysm clips, (2) human health studies related to the effects of exposure to nonionizing electromagnetic radiation, and (3) extant guidelines for limiting exposure of patients and medical personnel to the fields produced by NMR devices. On the basis of information available at the present time, it is concluded that the fields associated with the current generation of NMR devices do not pose a significant health risk in themselves. However, rigorous guidelines must be followed to avoid the physical interaction of these fields with metallic implants and medical electronic devices. 476 refs., 5 figs., 2 tabs.

  9. General transmission method based on PXI platform for physical experiments

    International Nuclear Information System (INIS)

    In this paper, a general method of data transmission system design on PXI platform is proposed. It can be used in readout system design for physical experiments. It aims at providing reusable and general interfaces for customized design of PXI while maintaining the transmission performance. It has three main features: (1) universal logic hardware interface, (2) ethernet based socket software interface, and (3) specific and simple data transmission protocol. Data transmission on PXI bus can be realized with the said two universal interfaces coordinated by this specific protocol. Test shows that this method is feasible and stable. This method can be easily reused in readout system designs for different experiments. (authors)

  10. Physical and biological predictors of radiation-induced whole lung injury: early results of a prospective study

    International Nuclear Information System (INIS)

    Purpose: To develop methods of predicting the pulmonary consequences of thoracic irradiation (RT) by prospectively studying changes in pulmonary function following RT. Methods: 105 patients receiving incidental partial lung irradiation during treatment of tumors in/around the thorax (lung-70, breast-18, lymphoma-4, misc-3) had whole lung function assessed (symptoms and pulmonary function tests [PFTs: FEV1-forced expiratory volume 1 sec; DLCO-diffusion capacity]) before and repeatedly 6-48 months following RT. All had computed tomography-based 3-dimensional (3D) dose calculations with lung density heterogeneity corrections for dose-volume histogram (DVH) and NTCP (normal tissue complication probability) calculations. Functional DVHs (DVfH) based on SPECT (single photon emission computed tomography) lung perfusion scans, and serial transforming growth factor-beta (TGF-β) levels were available in 50 and 30 patients, respectively. The incidence and severity of changes in whole lung function were correlated with clinical, physical and biological factors outlined in the results. Exploratory statistical analyses were preformed using chi-square, logistic regression, and multiple linear regression. Mean pt age=57, range 21-87; sex: 63 F, 42 M; 29 had chemotherapy (CT) before/with RT; Follow-up 6-48 months (mean 15, median 12). Results RT-induced symptoms developed in 26 patients (7-grade I-no intervention; 16 grade II-steroids; 3 grade III-oxygen and steroids). A mixed model based on pre-RT DLCO and CT-based NTCP was strongly predictive for the development of symptoms (p30 Gy. In patients with 'good' pre-RT PFTs, there may be a relationship between the % reduction in PFT and % lung volume receiving >30 Gy (figure). Conclusion: Whole lung injury (symptoms or PFT changes) appears to be related to a variety of physical, biological and clinical factors. The data suggest that no one variable is likely to be an adequate predictor and that multi-faceted predictive models will be

  11. Proteins Encoded in Genomic Regions Associated with Immune-Mediated Disease Physically Interact and Suggest Underlying Biology

    DEFF Research Database (Denmark)

    Rossin, Elizabeth J.; Hansen, Kasper Lage; Raychaudhuri, Soumya;

    2011-01-01

    Genome-wide association studies (GWAS) have defined over 150 genomic regions unequivocally containing variation predisposing to immune-mediated disease. Inferring disease biology from these observations, however, hinges on our ability to discover the molecular processes being perturbed by these...... that the RA and CD networks have predictive power by demonstrating that proteins in these networks, not encoded in the confirmed list of disease associated loci, are significantly enriched for association to the phenotypes in question in extended GWAS analysis. Finally, we test our method in 3 non-immune...... risk variants. It has previously been observed that different genes harboring causal mutations for the same Mendelian disease often physically interact. We sought to evaluate the degree to which this is true of genes within strongly associated loci in complex disease. Using sets of loci defined in...

  12. Methods of Efficient Study Habits and Physics Learning

    Science.gov (United States)

    Zettili, Nouredine

    2010-02-01

    We want to discuss the methods of efficient study habits and how they can be used by students to help them improve learning physics. In particular, we deal with the most efficient techniques needed to help students improve their study skills. We focus on topics such as the skills of how to develop long term memory, how to improve concentration power, how to take class notes, how to prepare for and take exams, how to study scientific subjects such as physics. We argue that the students who conscientiously use the methods of efficient study habits achieve higher results than those students who do not; moreover, a student equipped with the proper study skills will spend much less time to learn a subject than a student who has no good study habits. The underlying issue here is not the quantity of time allocated to the study efforts by the students, but the efficiency and quality of actions so that the student can function at peak efficiency. These ideas were developed as part of Project IMPACTSEED (IMproving Physics And Chemistry Teaching in SEcondary Education), an outreach grant funded by the Alabama Commission on Higher Education. This project is motivated by a major pressing local need: A large number of high school physics teachers teach out of field. )

  13. Fundamentals of bioinformatics and computational biology methods and exercises in matlab

    CERN Document Server

    Singh, Gautam B

    2015-01-01

    This book offers comprehensive coverage of all the core topics of bioinformatics, and includes practical examples completed using the MATLAB bioinformatics toolbox™. It is primarily intended as a textbook for engineering and computer science students attending advanced undergraduate and graduate courses in bioinformatics and computational biology. The book develops bioinformatics concepts from the ground up, starting with an introductory chapter on molecular biology and genetics. This chapter will enable physical science students to fully understand and appreciate the ultimate goals of applying the principles of information technology to challenges in biological data management, sequence analysis, and systems biology. The first part of the book also includes a survey of existing biological databases, tools that have become essential in today’s biotechnology research. The second part of the book covers methodologies for retrieving biological information, including fundamental algorithms for sequence compar...

  14. ACTIVE AND PARTICIPATORY METHODS IN BIOLOGY: PROBLEM-SOLVING

    OpenAIRE

    Adela NEMEŞ; Nicoleta IANOVICI

    2010-01-01

    We face with considerable challenge of developing students’ problem solving skills in our difficult environment. Good problem solving skills empower managers in their professional and personal lives. Problem solving skills are valued by academics and employers. The informations in Biology are often presented in abstract forms without contextualisation. Creative problem-solving process involves a few steps, which together provide a structured procedure for identifying challenges, generating id...

  15. Hybrid Dynamic Optimization Methods for Systems Biology with Efficient Sensitivities

    OpenAIRE

    Nicholas R. Lewis; John D. Hedengren; Haseltine, Eric L.

    2015-01-01

    In recent years, model optimization in the field of computational biology has become a prominent area for development of pharmaceutical drugs. The increased amount of experimental data leads to the increase in complexity of proposed models. With increased complexity comes a necessity for computational algorithms that are able to handle the large datasets that are used to fit model parameters. In this study the ability of simultaneous, hybrid simultaneous, and sequential algorithms are tested ...

  16. Biological methods of dye removal from textile effluents - A review

    OpenAIRE

    Archna; Lokesh KN; RR Sivakiran

    2012-01-01

    Textile dyes are molecules designed to impart permanent colours to textile fabrics. They pose an environmental problem due to their toxicity and decrease the aesthetic value of water bodies into which they are discharged. Current physico-chemical technologies for dye removal cannot remove all classes of dyes, and two or more technologies are usually combined to achieve satisfactory decolourisation efficiencies. Direct biological treatment using fungi or bacteria can also be employed, but nutr...

  17. A comparative analysis on computational methods for fitting an ERGM to biological network data

    Directory of Open Access Journals (Sweden)

    Sudipta Saha

    2015-03-01

    Full Text Available Exponential random graph models (ERGM based on graph theory are useful in studying global biological network structure using its local properties. However, computational methods for fitting such models are sensitive to the type, structure and the number of the local features of a network under study. In this paper, we compared computational methods for fitting an ERGM with local features of different types and structures. Two commonly used methods, such as the Markov Chain Monte Carlo Maximum Likelihood Estimation and the Maximum Pseudo Likelihood Estimation are considered for estimating the coefficients of network attributes. We compared the estimates of observed network to our random simulated network using both methods under ERGM. The motivation was to ascertain the extent to which an observed network would deviate from a randomly simulated network if the physical numbers of attributes were approximately same. Cut-off points of some common attributes of interest for different order of nodes were determined through simulations. We implemented our method to a known regulatory network database of Escherichia coli (E. coli.

  18. Group-theoretical method for physical property tensors of quasicrystals

    Institute of Scientific and Technical Information of China (English)

    Gong Ping; Hu Cheng-Zheng; Zhou Xiang; Wang Ai-Jun; Miao Ling

    2006-01-01

    In addition to the phonon variable there is the phason variable in hydrodynamics for quasicrystals. These two kinds of hydrodynamic variables have different transformation properties. The phonon variable transforms under the vector representation, whereas the phason variable transforms under another related representation. Thus, a basis (or a set of basis functions) in the representation space should include such two kinds of variables. This makes it more difficult to determine the physical property tensors of quasicrystals. In this paper the group-theoretical method is given to determine the physical property tensors of quasicrystals. As an illustration of this method we calculate the third-order elasticity tensors of quasicrystals with five-fold symmetry by means of basis functions. It follows that the linear phonon elasticity is isotropic, but the nonlinear phonon elasticity is anisotropic for pentagonal quasicrystals. Meanwhile, the basis functions are constructed for all noncrystallographic point groups of quasicrystals.

  19. Physical, chemical, and biological properties of soils in the city of Mariupol, Ukraine

    Science.gov (United States)

    Shekhovtseva, O. G.; Mal'tseva, I. A.

    2015-12-01

    Physicochemical and biological properties of urbanized soils in the city of Mariupol have been considered in comparison with the background soils. The parametrical characteristics (abundance and biomass) of soil algal groups, the content of humus, the reaction of soil solution, the content of heavy metals, and the particle size distributions of soils under different anthropogenic impacts have been assessed. The physicochemical properties of soils developing under urboecosystem conditions affect the number of structure-forming species, biomass, and proportions of soil algae. According to the particle size distribution, urban soils are classified among the medium and heavy loamy soils with the predominance of the clay and coarse silt fractions. The fractions of physical clay and clay are of highest importance for the existence of algae. The accumulation of heavy metals in the surface horizons of soils can stimulate or inhibit the development of algae depending on the metal concentration.

  20. Resource Letter: Bio-molecular Nano-machines: where Physics, Chemistry, Biology and Technology meet

    CERN Document Server

    Chowdhury, Debashish

    2008-01-01

    Cell is the structural and functional unit of life. This Resource Letter serves as a guide to the literature on nano-machines which drive not only intracellular movements, but also motility of the cell. These machines are usually proteins or macromolecular assemblies which require appropriate fuel for their operations. Although, traditionally, these machines were subjects of investigation in biology and biochemistry, increasing use of the concepts and techniques of physics in recent years have contributed to the quantitative understanding of the fundamental principles underlying their operational mechanisms. The possibility of exploiting these principles for the design and control of artificial nano-machines has opened up a new frontier in the bottom-up approach to nano-technology.

  1. Design in nature how the constructal law governs evolution in biology, physics, technology, and social organization

    CERN Document Server

    Bejan, Adrian

    2013-01-01

    In this groundbreaking book, Adrian Bejan takes the recurring patterns in nature—trees, tributaries, air passages, neural networks, and lightning bolts—and reveals how a single principle of physics, the constructal law, accounts for the evolution of these and many other designs in our world. Everything—from biological life to inanimate systems—generates shape and structure and evolves in a sequence of ever-improving designs in order to facilitate flow. River basins, cardiovascular systems, and bolts of lightning are very efficient flow systems to move a current—of water, blood, or electricity. Likewise, the more complex architecture of animals evolve to cover greater distance per unit of useful energy, or increase their flow across the land. Such designs also appear in human organizations, like the hierarchical “flowcharts” or reporting structures in corporations and political bodies. All are governed by the same principle, known as the constructal law, and configure and reconfigure themselves...

  2. Using Metaphor Theory to Examine Conceptions of Energy in Biology, Chemistry, and Physics

    Science.gov (United States)

    Lancor, Rachael

    2014-06-01

    Energy is one of the most important unifying themes in science. Yet the way energy is conceptualized varies depending on context. In this paper, the discourse used to explain the role of energy in systems from biology, chemistry, and physics is examined from the perspective of metaphor theory. Six substance metaphors for energy are identified in pedagogical discourse (i.e., textbooks and the science education literature): energy as a substance that can be accounted for, can flow, can be carried, can change forms, can be lost, and can be an ingredient, a product or stored in some way. Each of these conceptual metaphors highlight and obscure various characteristics of energy, and provide a set of frameworks that each afford a different understanding of the energy concept.

  3. Continuum methods of physical modeling continuum mechanics, dimensional analysis, turbulence

    CERN Document Server

    Hutter, Kolumban

    2004-01-01

    The book unifies classical continuum mechanics and turbulence modeling, i.e. the same fundamental concepts are used to derive model equations for material behaviour and turbulence closure and complements these with methods of dimensional analysis. The intention is to equip the reader with the ability to understand the complex nonlinear modeling in material behaviour and turbulence closure as well as to derive or invent his own models. Examples are mostly taken from environmental physics and geophysics.

  4. Dual energy computed tomography: Physical principles and methods

    OpenAIRE

    Κοντογιάννη, Λουκία

    2013-01-01

    The current thesis concerns Dual Energy Computed Tomography and specifically the physical principles and methods it is based on. Dual Energy CT offers the potential of not only anatomical, but also functional information from Computed Tomography (CT) exams. This is achieved by utilizing the energy dependence of X-rays’ attenuation within matter. In this way, materials are divided into those that are characterized by energy-dependent attenuation (strong spectral behavior), due t...

  5. Non-destructive methods to estimate physical aging of plywood

    OpenAIRE

    Bobadilla Maldonado, Ignacio; Santirso, María Cristina; Herrero Giner, Daniel; Esteban Herrero, Miguel; Iñiguez Gonzalez, Guillermo

    2011-01-01

    This paper studies the relationship between aging, physical changes and the results of non-destructive testing of plywood. 176 pieces of plywood were tested to analyze their actual and estimated density using non-destructive methods (screw withdrawal force and ultrasound wave velocity) during a laboratory aging test. From the results of statistical analysis it can be concluded that there is a strong relationship between the non-destructive measurements carried out, and the decline in the phys...

  6. Integrating writing into an introductory environmental science curriculum: Perspectives from biology and physics

    Science.gov (United States)

    Selkin, P. A.; Cline, E. T.; Beaufort, A.

    2008-12-01

    In the University of Washington, Tacoma's Environmental Science program, we are implementing a curriculum-wide, scaffolded strategy to teach scientific writing. Writing in an introductory science course is a powerful means to make students feel part of the scientific community, an important goal in our environmental science curriculum. Writing is already an important component of the UW Tacoma environmental science program at the upper levels: our approach is designed to prepare students for the writing-intensive junior- and senior-level seminars. The approach is currently being tested in introductory biology and physics before it is incorporated in the rest of the introductory environmental science curriculum. The centerpiece of our approach is a set of research and writing assignments woven throughout the biology and physics course sequences. The assignments progress in their degree of complexity and freedom through the sequence of introductory science courses. Each assignment is supported by a number of worksheets and short written exercises designed to teach writing and critical thought skills. The worksheets are focused on skills identified both by research in science writing and the instructors' experience with student writing. Students see the assignments as a way to personalize their understanding of basic science concepts, and to think critically about ideas that interest them. We find that these assignments provide a good way to assess student comprehension of some of the more difficult ideas in the basic sciences, as well as a means to engage students with the challenging concepts of introductory science courses. Our experience designing these courses can inform efforts to integrate writing throughout a geoscience or environmental science curriculum, as opposed to on a course-by-course basis.

  7. Linking Physical Dynamics and Biological Productivity in a Coastal Mesoscale Eddy

    Science.gov (United States)

    Simons, R. D.; Nishimoto, M. M.; Washburn, L.; Brown, K. S.; Siegel, D. A.

    2014-12-01

    The Santa Barbara Channel (SBC) eddy is a cyclonic mesoscale eddy located off the coast of Southern California, USA. In the summer of 1998 and 1999, the SBC eddy was surveyed for juvenile fishes. In 1998, very high numbers of juvenile fishes were observed within the eddy, but not in 1999. The ocean conditions that contributed to the differences in fish abundances inside the eddy were investigated with three-dimensional numerical modeling. The physical dynamics of the SBC eddy, which included eddy size, three-dimensional rotational structure, and isopycnal uplift, were evaluated using a three-dimensional Regional Ocean Modeling System (ROMS). The retention ability of the eddy was quantified using a three-dimensional particle tracking model driven by the ROMS. The physical dynamics and particle retention of the SBC eddy were found to differ significantly in 1998 and 1999. In 1998, when the SBC eddy was rotating at a steady rate spatially and temporally and cycling consistently in and out of solid-body rotation, the particle retention was high and the isopycnal uplift sustained. However in 1999, when the SBC eddy was rotating unsteadily in space and time and did not have periods of solid-body rotation, the particle retention was low and the isopycnal uplift unstable. We theorize that the steady symmetric rotation of the eddy in 1998 had two important impacts on the biological productivity inside the eddy. First, it provided a prolonged period of cold nutrient rich water uplifting into the euphotic zone, which stimulated productivity and consequently attracted zooplankton. Second, it allowed the zooplankton, prey for the juvenile fish, to be retained inside the eddy, which attracted the juvenile fish. We conclude that biological productivity inside mesoscale eddies may be linked to the stability of its three-dimensional rotational structure and consequently its ability to retain particles.

  8. The response of tidal morphologies to changing physical and biological forcings

    Science.gov (United States)

    D'Alpaos, A.; da Lio, C.; Marani, M.

    2009-12-01

    In times of natural climate changes and human interferences, tidal ecosystems are most exposed to possibly irreversible transformations, with far-reaching ecological, economical and social implications worldwide. Relative sea-level fluctuations, changes in nutrient and sediment loading, and ecological characteristics expose tidal ecosystems to responses which may or may not be reversible. Improving our understanding of the chief landforming processes which drive their morphogenesis and long-term evolution, is deemed to be a subject of leading theoretical and practical importance. We have modelled the joint evolution of tidal landforms and biota including the dynamics of intertidal vegetation, benthic microbial assemblages, erosional and depositional processes, local and general hydrodynamics, and relative sea-level change. Alternative stable states and punctuated equilibrium dynamics emerge, characterized by possible sudden transitions of the system, governed by vegetation type, disturbances of the benthic biofilm, sediment availability, wind climate, local hydrodynamics, and the vagaries of relative sea level rise. The existence of feedbacks between physical and biological processes affect trajectories characterizing the evolution of these ecosystems and the reversibility of such trajectories. They highlight the importance of the coupling between biological and sediment transport processes in determining the evolution of a tidal system as a whole.

  9. Integrated Ecological River Health Assessments, Based on Water Chemistry, Physical Habitat Quality and Biological Integrity

    Directory of Open Access Journals (Sweden)

    Ji Yoon Kim

    2015-11-01

    Full Text Available This study evaluated integrative river ecosystem health using stressor-based models of physical habitat health, chemical water health, and biological health of fish and identified multiple-stressor indicators influencing the ecosystem health. Integrated health responses (IHRs, based on star-plot approach, were calculated from qualitative habitat evaluation index (QHEI, nutrient pollution index (NPI, and index of biological integrity (IBI in four different longitudinal regions (Groups I–IV. For the calculations of IHRs values, multi-metric QHEI, NPI, and IBI models were developed and their criteria for the diagnosis of the health were determined. The longitudinal patterns of the river were analyzed by a self-organizing map (SOM model and the key major stressors in the river were identified by principal component analysis (PCA. Our model scores of integrated health responses (IHRs suggested that mid-stream and downstream regions were impaired, and the key stressors were closely associated with nutrient enrichment (N and P and organic matter pollutions from domestic wastewater disposal plants and urban sewage. This modeling approach of IHRs may be used as an effective tool for evaluations of integrative ecological river health..

  10. Visual Representations on High School Biology, Chemistry, Earth Science, and Physics Assessments

    Science.gov (United States)

    LaDue, Nicole D.; Libarkin, Julie C.; Thomas, Stephen R.

    2015-12-01

    The pervasive use of visual representations in textbooks, curricula, and assessments underscores their importance in K-12 science education. For example, visual representations figure prominently in the recent publication of the Next Generation Science Standards (NGSS Lead States in Next generation science standards: for states, by states. Achieve, Inc. on behalf of the twenty-six states and partners that collaborated on the NGSS, 2013). Although assessments of the NGSS have yet to be developed, most students are currently evaluated on their ability to interpret science visuals. While numerous studies exist on particular visuals, it is unclear whether the same types of visuals are emphasized in all science disciplines. The present study is an evaluation of the similarities and differences of visuals used to assess students' knowledge of chemistry, earth science, living environment (biology), and physics on the New York State Regents examination. Analysis of 266 distinct visual representations categorized across the four content examinations reveals that the frequency and type of visuals vary greatly between disciplines. Diagrams, Graphs, Tables, and Maps are the most prevalent across all science disciplines. Maps, Cartograms, and Time Charts are unique to the Earth Science examination, and Network Diagrams are unique to the living environment (biology) examination. This study identifies which representations are most critical for training students across the science disciplines in anticipation of the implementation and eventual assessment of the NGSS.

  11. The California Current system off Monterey, California: physical and biological coupling

    Science.gov (United States)

    Collins, C. A.; Pennington, J. T.; Castro, C. G.; Rago, T. A.; Chavez, F. P.

    2003-08-01

    Repeated hydrobiological surveys over the period 1988-2002 perpendicular to the central California coast indicate strong coupling between physical circulation and biological production. An equatorward-flowing jet about 100-200 km from shore marked the inshore edge of the California Current (CC). This "CC Jet" had its highest velocities during late winter and spring. The jet divided inshore, biologically productive waters from offshore, low-production waters. Mean flow in the inshore waters is poleward. However, this flow is interrupted in late spring and summer by a surface-enhanced, equatorward-flowing, coastal upwelling jet. The upwelling jet coincides with maxima of nutrients, chlorophyll- a and primary production. Annual variability in the inshore zone is related to (1) vertical pycnocline movements associated with geostrophic adjustments to accelerations of the California Current system, and (2) coastal upwelling. In offshore waters, the annual cycle accounted for a small fraction of the variability, indicating the dominance of eddies and meanders in this zone (J. Geophys. Res. 92 (1987) 12 947). The offshore regime was mesotrophic to oligotrophic, with a subsurface chlorophyll- a maximum above the nutricline. Considerable subduction may occur under the California Current jet and be an important process in the export of biogenic material to the deep sea.

  12. Human Development VII: A Spiral Fractal Model of Fine Structure of Physical Energy Could Explain Central Aspects of Biological Information, Biological Organization and Biological Creativity

    Directory of Open Access Journals (Sweden)

    Søren Ventegodt

    2006-01-01

    Full Text Available In this paper we have made a draft of a physical fractal essence of the universe, a sketch of a new cosmology, which we believe to lay at the root of our new holistic biological paradigm. We present the fractal roomy spiraled structures and the energy-rich dancing “infinite strings” or lines of the universe that our hypothesis is based upon. The geometric language of this cosmology is symbolic and both pre-mathematical and pre-philosophical. The symbols are both text and figures, and using these we step by step explain the new model that at least to some extent is able to explain the complex informational system behind morphogenesis, ontogenesis, regeneration and healing. We suggest that it is from this highly dynamic spiraled structure that organization of cells, organs, and the wholeness of the human being including consciousness emerge. The model of ““dancing fractal spirals” carries many similarities to premodern cultures descriptions of the energy of the life and universe. Examples are the Native American shamanistic descriptions of their perception of energy and the old Indian Yogis descriptions of the life-energy within the body and outside. Similar ideas of energy and matter are found in the modern superstring theories. The model of the informational system of the organism gives new meaning to Bateson’s definition of information: “A difference that makes a difference”, and indicates how information-directed self-organization can exist on high structural levels in living organisms, giving birth to their subjectivity and consciousness.

  13. Premature chromosome condensation: A novel method for biological dosimetry

    International Nuclear Information System (INIS)

    In this study, we have investigated the utility of different test systems for biological dosimetry and possible their application for therapy regime. Human peripheral blood lymphocytes were X-irradiated and mixed in different proportions with unirradiated lymphocytes. The frequencies of chromosomal aberrations were determined by the formation of dicentrics, excess of premature chromosome condensation fragments and micronuclie in cytochalasin B-blocked binucleated cells. These responses were with regard to estimate the dose received and to determine the population of unexposed cells (useful for the purpose of therapy) are discussed. 6 refs, 3 figs, 3 tabs

  14. Inaccuracies of nitric oxide measurement methods in biological media

    OpenAIRE

    Hunter, Rebecca A.; Storm, Wesley L.; Coneski, Peter N.; Schoenfisch, Mark H.

    2013-01-01

    Despite growing reports on the biological action of nitric oxide (NO) as a function of NO payload, the validity of such work is often questionable due to the manner in which NO is measured and/or the solution composition in which NO is quantified. To highlight the importance of measurement technique for a given sample type, NO produced from a small molecule NO donor (N-diazeniumdiolated l-proline, PROLI/NO) and a NO-releasing xerogel film were quantified in a number of physiological buffers a...

  15. The Collective Vector method in nuclear and atomic physics

    International Nuclear Information System (INIS)

    We present a brief review of the method of the Collective Vector (CV) and its use in conjunction with the Lanczos algorithm (LA). The combination of these two ideas produces a method for contracting super-large hamiltonians (up to 106 x 106) by factors of 1000 or more. The contracted hamiltonians, which we call quasi-hamiltonians, typically have dimensions of the order of 102 x 102 and produce corresponding quasi-spectra with associated quasi-eigenfunctions which reproduce the features of the full microscopic spectrum thru the conservation of the spectral moments. Examples of applications to both nuclear and atomic physics are given demonstrating the convergence properties of the method. The application of the LA/CV approach to the problem of modelling nuclear level densities is described and finally we discuss the possibility of conjoining new collective models of nuclear structure with the LA/CV method. 13 refs., 4 figs

  16. Effects of physical therapy for the management of patients with ankylosing spondylitis in the biological era.

    Science.gov (United States)

    Giannotti, Erika; Trainito, Sabina; Arioli, Giovanni; Rucco, Vincenzo; Masiero, Stefano

    2014-09-01

    Exercise is considered a fundamental tool for the management of ankylosing spondylitis (AS), in combination with pharmacological therapy that with the advent of biological therapy has improved dramatically the control of signs and symptoms of this challenging disease. Current evidence shows that a specific exercise protocol has not been validated yet. The purpose of this review is to update the most recent evidence (July 2010-November 2013) about physiotherapy in AS, analyzing the possible role and synergistic interactions between exercise and biological drugs. From 117 studies initially considered, only 15 were included in the review. The results support a multimodal approach, including educational sessions, conducted in a group setting, supervised by a physiotherapist and followed by a maintaining home-based regimen. Spa exercise and McKenzie, Heckscher, and Pilates methods seem promising in AS rehabilitation, but their effectiveness should be further investigated in future randomized controlled trials (RCTs). When performed in accordance with the American College of Sports Medicine guidelines, cardiovascular training has been proven safe and effective and should be included in AS rehabilitation protocols. Exercise training plays an important role in the biological era, being now applicable to stabilized patients, leading ultimately to a better management of AS by physiatrists and rheumatologists throughout the world. On the basis of the current evidence, further research should aim to determine which exercise protocols should be recommended. PMID:24797772

  17. The Clarinet Reed: AN Introduction to its Biology, Chemistry, and Physics

    Science.gov (United States)

    Casadonte, Donald Jay

    Although clarinet reeds have been used for over two-hundred years, there has been little scientific study of the reed, either from a material science or engineering perspective. This document is intended to be the first large-scale study of the clarinet reed covering its biology, chemistry and physics. The reed is made, most often, from cane--Arundo donax. We present a complete atlas of the anatomy of Arundo donax, and examine the role of each of the cellular components in the clarinet reed performance. We examine the three principal chemical components of the processed clarinet reed: cellulose, xylan, and lignin through the use of instrumental analysis. We examine the breakdown pathways of the clarinet reed, and isolate five: (1) decrystallization of the cellulose microstructure, (2) removal of xylan by saliva, (3) plasticization of the reed material due to alkalai attack in saliva, (4) the culturing of a bacterium, Staph Epidermitis, in the cell wall matrix, (5) density changes due to salival coating of the reed. The physics of the reed is examined, and a finite element model of the modal shapes is presented. We present a theoretical treatment of the two modes of excitation of the reed, a low frequency mode (normal playing mode) due to vortex shedding, and a high frequency mode which is associated with reed squeak.

  18. Breathing of the Biosphere: How Physics sets the Limits, and Biology Does the Work (Invited)

    Science.gov (United States)

    Baldocchi, D. D.

    2009-12-01

    Trace gas concentrations in the atmosphere are a consequence of fluxes between vegetation and the atmosphere. Predicting the rates of these fluxes is extremely complicated because the biosphere is a complex adaptive system that consists of a multitude of physical and biological processes that vary across 14 orders of magnitude in time and space. One challenge in predicting trace gas fluxes is to know when to lump and when to split this information into coarser or finer levels of detail. Plants, for example, abhor a vacuum and tend to fill niches if there is ample water, sunlight and soil. So ultimately, the upper limit of water, carbon and energy fluxes is set by amount of energy intercepted at the Earth’s surface, which scales with the solar constant. In addition, physics limits the supply and demand of resources that sustain plants, so many ecological scaling rules emerge; this reduces the need to consider every species, plant and leaf individually when assessing net and gross exchanges of trace gases between vegetation and the atmosphere. This trend towards the role of simplicity begins to fail when one starts to evaluate fluxes associated with microbes, like methane and nitrous oxide; microbes live in heterogeneous environments and exploit numerous routes to extract energy from their environment. Case studies, pertaining to the title, will be discussed using eddy covariance flux measurements from our field sites (peatland pasture, savanna woodland, grassland, deciduous and boreal forests), the FLUXNET network and leaf, canopy and planetary boundary-layer scale biophysical models.

  19. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  20. Experimental evidence in support of the biological effects and physical basis of homeopathic potencies

    Directory of Open Access Journals (Sweden)

    Nirmal Sukul

    2012-09-01

    Full Text Available Background: Homeopathic potencies 12 cH and above cross the Avogadro number and, for this, do not contain any original drug molecules. Two major problems involved in the scientific study of potencies are (1 understanding the physical basis of potencies and (2 demonstrating the biological effects of potencies. The present study aims to address these questions. Methods and Results: In course of our experimental studies spanned over more than 30 years we have demonstrated significant effects of homeopathic potencies on man, animals and plants. We have also showed that potencies could be differentiated through their electronic spectra, and this difference in spectra can be attributed to the electron transfer interaction. In a molecular complex, electron of one molecule absorbs a quantum of visible radiation and is excited, not to a higher energy level of this molecule, but to one of the vacant high energy levels of the neighboring molecules. This process is known as electron or charge transfer interaction. This has been demonstrated in Iodine Ó© in two different solvents of CCl4 and aqueous ethanol (Sukul N C, Environ Ecol 17,866-872, 1999. We have further demonstrated that the effect of a homeopathic potency can be transmitted from one part of a plant to another, and also from one plant to another through water. I am presenting here a few selected cases of our experimental studies. Potentized Nux vomica significantly reduced ethanol consumption in rats by 73.7%and ethanol-induced sleep time in albino mice by 44.4%. Causticum 30 C and Rhus tox 30 C produced anti-inflamatory and anti-nocicptive effect on adjuvant arthritis in albino rats. Potentized homeopathic drugs reduced microfilaraemia by 28 to 100% and filariasis in two villages of West Bengal endemic for Bancroftian filaiasis. Potentized Cina and Thuja ameliorated trichinellosis in mice reducing larval population in muscles by 84% and 68%, respectively. Potencies of Agaricus and Nux

  1. Accurate measurement and physical insight: The X-ray extended range technique for fundamental atomic physics, condensed matter research and biological sciences

    International Nuclear Information System (INIS)

    Research in core physics or atomic and condensed matter science is increasingly relevant for diverse fields and are finding application in chemistry, engineering and biological sciences, linking to experimental research at synchrotrons, reactors and specialised facilities. Over recent synchrotron experiments and publications we have developed methods for measuring the absorption coefficient far from the edge and in the XAFS (X-ray absorption fine structure) region in neutral atoms, simple compounds and organometallics reaching accuracies of below 0.02%. This is 50-500 times more accurate than earlier methods, and 50-250 times more accurate than claimed uncertainties in theoretical computations for these systems. The data and methodology are useful for a wide range of applications, including major synchrotron and laboratory techniques relating to fine structure, near-edge analysis and standard crystallography. Experiments are sensitive to theoretical and computational issues, including correlation between convergence of electronic and atomic orbitals and wavefunctions. Hence, particularly in relation to the popular techniques of XAFS and XANES (X-ray absorption near-edge structure), this development calls for strong theoretical involvement but has great applications in solid state structural determination, catalysis and enzyme environments, active centres of biomolecules and organometallics, phase changes and fluorescence investigations and others. We discuss key features of the X-ray extended range technique (XERT) and illustrate applications.

  2. The Gaussian CLs method for searches of new physics

    Science.gov (United States)

    Qian, X.; Tan, A.; Ling, J. J.; Nakajima, Y.; Zhang, C.

    2016-08-01

    We describe a method based on the CLs approach to present results in searches of new physics, under the condition that the relevant parameter space is continuous. Our method relies on a class of test statistics developed for non-nested hypotheses testing problems, denoted by ΔT, which has a Gaussian approximation to its parent distribution when the sample size is large. This leads to a simple procedure of forming exclusion sets for the parameters of interest, which we call the Gaussian CLs method. Our work provides a self-contained mathematical proof for the Gaussian CLs method that explicitly outlines the required conditions. These conditions are milder than that required by Wilks' theorem to set confidence intervals (CIs). We illustrate the Gaussian CLs method in an example of searching for a sterile neutrino, where the CLs approach was rarely used before. We also compare data analysis results produced by the Gaussian CLs method and various CI methods to showcase their differences.

  3. 7th International Conference on Mathematical Methods in Physics

    Science.gov (United States)

    Bonora, L.; Bytsenko, A. A.; Guimarães, M. E. X.; Helayël-Neto, J. A.

    The 7th International Conference on Mathematical Methods in Physics took place in the Centro Brasileiro de Pesquisas Físicas (CBPF/MCT), Rio de Janeiro - RJ, Brazil, from 16 to 20 April 2012, and was jointly organized by the following Institutions: Centro Brasileiro de Pesquisas Físicas (CBPF/MCT), The Abdus Salam International Centre for Theoretical Physics (ICTP, Italy), Instituto Nacional de Matemática Pura e Aplicada (IMPA, Brazil), The Academy of Sciences for the Developing World (TWAS, Italy) and The Scuola Internazionale di Studi Avanzati (SISSA,Italy). The Organizing Committees were composed by: E. ABDALLA (USP, Brazil), L. BONORA (SISSA, Italy), H. BURSZTYN (IMPA, Brazil), A. A. BYTSENKO (UEL, Brazil), B. DUBROVIN (SISSA, Italy), M.E.X. GUIMARÃES (UFF, Brazil), J.A. HELAYËL-NETO (CBPF, Brazil). Advisory Committee: A. V. ASHTEKAR (Penn State University, U.S.A.), V. M. BUCHSTABER (Steklov Mathematical Institute, Russia), L. D. FADDEEV (St. Petersburg Dept. of Steklov Mathematical Institute, Russia), I. M. KRICHEVER (Columbia Univ., U.S.A./ Landau Institute of Theoretical Physics, Russia), S. P. NOVIKOV (Univ. of Maryland, U.S.A./Landau Institute of Theoretical Physics, Russia), J. PALIS (IMPA, Brazil), A. QADIR (National University of Sciences and Technology, Pakistan), F. QUEVEDO (ICTP, Italy), S. RANDJBAR-DAEMI (ICTP, Italy), G. THOMPSON (ICTP, Italy), C. VAFA (Harvard University, U.S.A.). The Main Goal: The aim of the Conference was to present the latest advances in Mathematical Methods of Physics to researchers, young scientists and students of Latin America in general, and Brazil in particular, in the areas of High Energy Physics, Cosmology, Mathematical Physics and Applied Mathematics. The main goal was to promote an updating of knowledge and to facilitate the interaction between mathematicians and theoretical physicists, through plenary sessions and seminars. This Conference can be considered as a part of a network activity in a special effort to

  4. Methods for Analyzing Pathways through a Physics Major

    OpenAIRE

    Aiken, John M.; Caballero, Marcos D.

    2016-01-01

    Physics Education Research frequently investigates what students studying physics do on small time scales (e.g. single courses, observations within single courses), or post-education time scales (e.g., what jobs do physics majors get?) but there is little research into how students get from the beginning to the end of a physics degree. Our work attempts to visualize students paths through the physics major, and quantitatively describe the students who take physics courses, receive physics deg...

  5. Development of a coupled physical-biological ecosystem model ECOSMO - Part I: Model description and validation for the North Sea

    DEFF Research Database (Denmark)

    Schrum, Corinna; Alekseeva, I.; St. John, Michael

    2006-01-01

    A 3-D coupled biophysical model ECOSMO (ECOSystem MOdel) has been developed. The biological module of ECOSMO is based on lower trophic level interactions between two phyto- and two zooplankton components. The dynamics of the different phytoplankton components are governed by the availability of the...... macronutrients nitrogen, phosphate and silicate as well as light. Zooplankton production is simulated based on the consumption of the different phytoplankton groups and detritus. The biological module is coupled to a nonlinear 3-D baroclinic model. The physical and biological modules are driven by surface...

  6. Dosing method of physical activity in aerobics classes for students

    Directory of Open Access Journals (Sweden)

    Beliak Yu.I.

    2014-10-01

    Full Text Available Purpose : reasons for the method of dosing of physical activity in aerobics classes for students. The basis of the method is the evaluation of the metabolic cost of funds used in them. Material : experiment involved the assessment of the pulse response of students to load complexes classical and step aerobics (n = 47, age 20-23 years. In complexes used various factors regulating the intensity: perform combinations of basic steps, involvement of movements with his hands, holding in hands dumbbells weighing 1kg increase in the rate of musical accompaniment, varying heights step platform. Results . on the basis of the relationship between heart rate and oxygen consumption was determined by the energy cost of each admission control load intensity. This indicator has been used to justify the intensity and duration of multiplicity aerobics. Figure correspond to the level of physical condition and motor activity deficits students. Conclusions : the estimated component of this method of dosing load makes it convenient for use in automated computer programs. Also it can be easily modified to dispense load other types of recreational fitness.

  7. A Data Transmission Method Based on Ethernet Physical Layer for Particle Physics Experiment

    CERN Document Server

    Xi-Ru, Huang; Jia-Jun, Zheng

    2015-01-01

    Due to the advantages of universality, flexibility and high performance, fast Ethernet is widely used in readout system design of modern particle physics experiments. However, Ethernet is usually used together with TCP/IP protocol stack, which makes it difficult to be implemented because designers have to use operating system to process this protocol. Furthermore, TCP/IP protocol degrades the transmission efficiency and real-time performance. To maximize the performance of Ethernet in physics experiment applications, a data readout method based on physical layer (PHY) is proposed in this paper. In this method, TCP/IP protocol is forsaken and replaced with a customized and simple protocol, which make it easier to be implemented. On each readout module, data from front-end electronics is first fed into an FPGA for protocol processing and then sent out to a PHY chip controlled by this FPGA for transmission. This kind of data path is fully implemented by hardware. While from the side of data acquisition system (D...

  8. Dating methods enter high-school physics curriculum

    International Nuclear Information System (INIS)

    The new curriculum of physics of the upper forms in French grammar schools includes a part dedicated to ''nuclear transformations''. One of the applications most often considered in manuals is isotopic dating and generally several methods are explained to pupils: carbon 14 dating, potassium-argon dating (used for dating ancient lava layers) and uranium-thorium dating (used for dating corals). The author reviews with a critical eye the content of manuals and laments through concrete examples the lack of exactness and accuracy of some presentations. (A.C.)

  9. Progress report, Biology and Health Physics Division, April 1 to June 30, 1978

    International Nuclear Information System (INIS)

    The effects of neutrons reflected by the body of a wearer of a neutron threshold activation detector have been determined experimentally. Agreement with the previously calculated effect was good. Calculations and experiments are in progress on the response of organic scintillators to fast neutron and gamma radiation. Other work in health physics included examination of the feasibility of using water-permeable membranes to separate HTO from HT and design of instrumentation for measuring discharge of radio-xenons from a Mo-99 production plant. A variety of environmental research programs included studies dealing with the effects of thermal stress on food-chain organisms in fresh water and mobility of arsenic in sand columns. Computer studies on linked health records will be phased out at Chalk River Nuclear Laboratories. Similar work will be performed at Statistics Canada, the University of British Columbia, and in Hawaii under its cancer register. Work in biology has continued to focus upon the effects of radiation on a variety of organisms, ranging from bacterial viruses to humans. The principal target for long-term biological effects of radiation on all living organisms is DNA. The chemical nature of damage caused in DNA by radiation and the response of cells to this damage is being studied by a variety of biochemical and genetic techniques. Studies on cultured skin cells from various humans have shown interesting characteristics associated with different rare hereditary diseases. It has now been shown that repair-deficient ataxia telangiectasia (AT) cells are surprisingly different from repair-proficient AT cells in their reponse to ultraviolet light at 313 nm. (OST)

  10. Biological and Physical Drivers of Coarse Woody Debris Respiration Following Moderate Forest Disturbance

    Science.gov (United States)

    Schmid, A. V.; Franklin, R. B.; Vogel, C. S.; Liebman, E.; Curtis, P.; Gough, C. M.

    2014-12-01

    Forest disturbances that cause plant mortality alter the net carbon (C) balance by increasing heterotrophic respiration associated with coarse woody debris (CWD) decomposition. Whether a forest transitions from a C sink to source following disturbance is largely a function of the quantity of additional CWD produced and the rate of woody debris decomposition. Coarse woody debris temperature, moisture, and microbial community composition are known to drive rates of heterotrophic respiration, but rarely have these factors been studied together across a gradient of wood decay and over time following disturbance. We used a large-scale experimental disturbance, in which early successional aspen (Populus spp.) and birch (Betula papyrifera) were killed via stem girdling within a 39 ha area, to study the effects of moderate disturbance on the forest C cycle. We quantified changes over time in CWD mass for a decade, before and after disturbance. We then conducted point measurements of CWD respiration, temperature and moisture, and quantified extracellular enzyme activity of enzymes associated with wood decomposition for five classes varying in extent of decay and standing woody debris. Process and inventory data are being used to estimate ecosystem CO2 efflux from CWD, which we will contrast with net ecosystem production (NEP) determined from long-term eddy covariance measurements of net CO2 exchange between the forest and atmosphere at the University of Michigan Biological Station (US-UMd) Ameriflux site. Our results will improve ecosystem model predictions of CWD respiration by incorporating both physical factors, such as temperature and wood moisture content, and biological factors, such as extracellular enzymatic activity of different functional types of decomposers.

  11. A magnetic method to concentrate and trap biological targets

    KAUST Repository

    Li, Fuquan

    2012-11-01

    Magnetoresistive sensors in combination with magnetic particles have been used in biological applications due to, e.g., their small size and high sensitivity. A growing interest is to integrate magnetoresistive sensors with microchannels and electronics to fabricate devices that can perform complex analyses. A major task in such systems is to immobilize magnetic particles on top of the sensor surface, which is required to detect the particles\\' stray field. In the presented work, a bead concentrator, consisting of gold microstructures, at the bottom of a microchannel, is used to attract and move magnetic particles into a trap. The trap is made of a chamber with a gold microstructure underneath and is used to attract and immobilize a defined number of magnetic beads. In order to detect targets, two kinds of solutions were prepared; one containing only superparamagnetic particles, the other one containing beads with the protein Bovine serum albumin as the target and fluorescent markers. Due to the size difference between bare beads and beads with target, less magnetic beads were immobilized inside the volume chamber in case of magnetic beads with target as compared to bare magnetic beads. © 1965-2012 IEEE.

  12. Metabolomics methods for the synthetic biology of secondary metabolism.

    Science.gov (United States)

    Nguyen, Quoc-Thai; Merlo, Maria E; Medema, Marnix H; Jankevics, Andris; Breitling, Rainer; Takano, Eriko

    2012-07-16

    Many microbial secondary metabolites are of high biotechnological value for medicine, agriculture, and the food industry. Bacterial genome mining has revealed numerous novel secondary metabolite biosynthetic gene clusters, which encode the potential to synthesize a large diversity of compounds that have never been observed before. The stimulation or "awakening" of this cryptic microbial secondary metabolism has naturally attracted the attention of synthetic microbiologists, who exploit recent advances in DNA sequencing and synthesis to achieve unprecedented control over metabolic pathways. One of the indispensable tools in the synthetic biology toolbox is metabolomics, the global quantification of small biomolecules. This review illustrates the pivotal role of metabolomics for the synthetic microbiology of secondary metabolism, including its crucial role in novel compound discovery in microbes, the examination of side products of engineered metabolic pathways, as well as the identification of major bottlenecks for the overproduction of compounds of interest, especially in combination with metabolic modeling. We conclude by highlighting remaining challenges and recent technological advances that will drive metabolomics towards fulfilling its potential as a cornerstone technology of synthetic microbiology. PMID:22710183

  13. Recent molecular biology methods for foulbrood and nosemosis diagnosis.

    Science.gov (United States)

    Rivière, M P; Ribière, M; Chauzat, M P

    2013-12-01

    Honey-bee colony losses are an increasing problem in Western countries. There are many different causes, including infections due to various pathogens. Molecular biology techniques have been developed to reliably detect and identify honey-bee pathogens. The most sensitive, specific and reliable is the quantitative real-time polymerase chain reaction (qPCR) methodology. This review of the literature describes various studies where qPCR was used to detect, identify and quantify four major honey-bee pathogens: the bacteria Paenibacillus larvae and Melissococcus plutonius (the causative agents of American foulbrood and European foulbrood, respectively) and the microsporidia Nosema apis and N. ceranae (the causative agents of nosemosis). The application of qPCR to honey-bee pathogens is very recent, and techniques are expected to improve rapidly, leading to potential new prospects for diagnosis and control. Thus, qPCR techniques could shortly become a powerful tool for investigating pathogenic infections and increasing our understanding of colony losses. PMID:24761740

  14. Marine rock physical flume experiment: The method of seafloor shallow sediment recognition by ultrasonic physical attributes

    Science.gov (United States)

    Wang, Qing; Wang, Yun; Hu, Xiaoya; Zhang, Jianli; Guo, Shiguang

    2015-04-01

    It's a key problem to recognize the kinds of sediments in the ocean bottom during an acoustic survey or seismic exploration. In this paper, an ultrasonic rock physics experiment was introduced in the flume, which simulated different sedimentary types of ocean bottom, such as stone, fine sand, coarse sand, silt and cement. After processing the simulated acoustic data, some physical attributes, which are sensitive to different types of sediment, was found. In which, the weighted average frequency attribute can distinguish the coarse sand, silt and stone substrate if combined with sweetness attribute. The instantaneous quality factor (Q) attribute highlights the cement restrained with the weighted average frequency attribute. Through analyzing the relationships between porosity, density and these sensitive acoustic attributes, the types of sediment in the flume can be deduced and inversed by artificial neural network method.

  15. Evolution of physical and biological characteristics of mesoscale eddy in north-central Red Sea

    KAUST Repository

    Zarokanellos, Nikolaos

    2015-04-01

    Eddies appear to be important to both the physical and biogeochemical dynamics of the Red Sea. Numerical simulations of physical dynamics and remote sensing studies of chlorophyll concentration and sea surface height in the Red Sea indicate their importance to the upper portions of the sea (Raitsos et al., 2013; Yao et al., 2014; Zhan et al., 2014). Despite their apparent importance, process studies of these eddies have been lacking. In March 2013 we began an extended observational study of the north-central Red Sea (NCRS) where anticyclonic eddies have been observed. The study began with a ship-based characterization of the eddy and was followed by a three-month observational time series using an autonomous glider equipped with a CTD, oxygen sensor, and optical sensors for chlorophyll, CDOM and optical backscatter. The ship-based study captured an initial snapshot of an anticyclonic eddy and it\\'s associated biological and bio-optical distributions. Initially, chlorophyll distributions tended to mirror the density distribution, with deeper isopycnals and chlorophyll maximum depth in the anticyclonic eddy center. The anticyclone eddy in March had an along basin diameter of 150 km, penetrated vertically less than 150 m and elevated near surface chlorophyll concentrations appeared along its outer boundary. The shallowing of the pycnocline of the outer boundaries of the anticyclone eddy on March may elevate nutrients into the lower euphotic zone, contributing to phytoplankton productivity and biomass within the eddy. This eddy contains most of the kinetic energy of the region with the maximum velocities up to 30 - 35 cm/s. The eddy appeared to interact with the coastal reefs where exchange particulate and dissolved matter may occur. The autonomous glider provided the spring-to-summer progression of the system with increasing stratification, shallowing of the subsurface chlorophyll maximum, and fluctuations in the position and intensity of the eddy. Our glider effort

  16. Physical chemical and citotoxic evaluation of highly diluted solutions of Euphorbia tirucalli L. prepared through the fifty milesimal homeopathic method

    Directory of Open Access Journals (Sweden)

    Carlos Renato Zacharias

    2010-07-01

    Full Text Available Background: although Hahnemann described the fifty-milesimal (LM method in the 6th edition of the Organon of the Medical Art, very little research has been carried out on the physical chemical properties of these homeopathic preparations. Furthermore, there is still no evidence allowing for the correlation between the alleged physical chemical properties and the biological effects of high dilutions. Aims: to evaluate physical chemical characteristics of LM preparations including electrical conductivity, pH and refraction index, and their effect on biological experimental models. Materials and methods: preparations tested for physical chemical analysis were dilutions 1 lm to 10 lm of Euphorbia tirucalli L. prepared from the latex and the juice of the plant. To rule the seasonal characteristics of this plant, 2 different populations were used, one collected in June 2007 and the other in May 2008. Furthermore, the cytotoxic effect of Euphorbia tirucalli 5 lm was tested on human breast cancer cells (MCF7 through MTT assay. Some differences among the two collections were observed. However, any clear correlation could be observed between physical chemical properties and biological activity.

  17. Specific methods for theophylline assay in biological samples

    International Nuclear Information System (INIS)

    The objective of monitoring theophylline plasma levels in in therapeutic work is well established, and the consequences of using unspecific analytical methods are obvious. For the determination of pharmacokinetic parameters, concentrations far below the therapeutic range must often be measured. Interferences acceptable in therapeutic monitoring of theophylline could cause severe inaccuracy at these drug levels. The term specificity and its meaning are discussed in general and in relation to the different steps of the analytical procedure (e.g., sampling and sample work-up). Different analytical methods for theophylline are discussed in terms of specificity. Plasma concentrations of paraxanthine (1,7-dimethylxanthine) - a metabolite of caffeine - as high as 3 μg/ml have been observed, and the compound can interfere in various theophylline assay methods. An example is given of the pharmacokinetic consequences. (author)

  18. NATO Advanced Study Institute on Methods in Computational Molecular Physics

    CERN Document Server

    Diercksen, Geerd

    1992-01-01

    This volume records the lectures given at a NATO Advanced Study Institute on Methods in Computational Molecular Physics held in Bad Windsheim, Germany, from 22nd July until 2nd. August, 1991. This NATO Advanced Study Institute sought to bridge the quite considerable gap which exist between the presentation of molecular electronic structure theory found in contemporary monographs such as, for example, McWeeny's Methods 0/ Molecular Quantum Mechanics (Academic Press, London, 1989) or Wilson's Electron correlation in moleeules (Clarendon Press, Oxford, 1984) and the realization of the sophisticated computational algorithms required for their practical application. It sought to underline the relation between the electronic structure problem and the study of nuc1ear motion. Software for performing molecular electronic structure calculations is now being applied in an increasingly wide range of fields in both the academic and the commercial sectors. Numerous applications are reported in areas as diverse as catalysi...

  19. Literature in Focus: Statistical Methods in Experimental Physics

    CERN Multimedia

    2007-01-01

    Frederick James was a high-energy physicist who became the CERN "expert" on statistics and is now well-known around the world, in part for this famous text. The first edition of Statistical Methods in Experimental Physics was originally co-written with four other authors and was published in 1971 by North Holland (now an imprint of Elsevier). It became such an important text that demand for it has continued for more than 30 years. Fred has updated it and it was released in a second edition by World Scientific in 2006. It is still a top seller and there is no exaggeration in calling it «the» reference on the subject. A full review of the title appeared in the October CERN Courier.Come and meet the author to hear more about how this book has flourished during its 35-year lifetime. Frederick James Statistical Methods in Experimental Physics Monday, 26th of November, 4 p.m. Council Chamber (Bldg. 503-1-001) The author will be introduced...

  20. Methods for Analyzing Pathways through a Physics Major

    CERN Document Server

    Aiken, John M

    2016-01-01

    Physics Education Research frequently investigates what students studying physics do on small time scales (e.g. single courses, observations within single courses), or post-education time scales (e.g., what jobs do physics majors get?) but there is little research into how students get from the beginning to the end of a physics degree. Our work attempts to visualize students paths through the physics major, and quantitatively describe the students who take physics courses, receive physics degrees, and change degree paths into and out of the physics program at Michigan State University.

  1. WE-E-17A-07: Patient-Specific Mathematical Neuro-Oncology: Biologically-Informed Radiation Therapy and Imaging Physics

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, K; Corwin, D [Northwestern University, Chicago, IL (United States); Rockne, R

    2014-06-15

    Purpose: To demonstrate a method of generating patient-specific, biologically-guided radiation therapy (RT) plans and to quantify and predict response to RT in glioblastoma. We investigate the biological correlates and imaging physics driving T2-MRI based response to radiation therapy using an MRI simulator. Methods: We have integrated a patient-specific biomathematical model of glioblastoma proliferation, invasion and radiotherapy with a multiobjective evolutionary algorithm for intensity-modulated RT optimization to construct individualized, biologically-guided plans. Patient-individualized simulations of the standard-of-care and optimized plans are compared in terms of several biological metrics quantified on MRI. An extension of the PI model is used to investigate the role of angiogenesis and its correlates in glioma response to therapy with the Proliferation-Invasion-Hypoxia- Necrosis-Angiogenesis model (PIHNA). The PIHNA model is used with a brain tissue phantom to predict tumor-induced vasogenic edema, tumor and tissue density that is used in a multi-compartmental MRI signal equation for generation of simulated T2- weighted MRIs. Results: Applying a novel metric of treatment response (Days Gained) to the patient-individualized simulation results predicted that the optimized RT plans would have a significant impact on delaying tumor progression, with Days Gained increases from 21% to 105%. For the T2- MRI simulations, initial validation tests compared average simulated T2 values for white matter, tumor, and peripheral edema to values cited in the literature. Simulated results closely match the characteristic T2 value for each tissue. Conclusion: Patient-individualized simulations using the combination of a biomathematical model with an optimization algorithm for RT generated biologically-guided doses that decreased normal tissue dose and increased therapeutic ratio with the potential to improve survival outcomes for treatment of glioblastoma. Simulated T2-MRI

  2. WE-E-17A-07: Patient-Specific Mathematical Neuro-Oncology: Biologically-Informed Radiation Therapy and Imaging Physics

    International Nuclear Information System (INIS)

    Purpose: To demonstrate a method of generating patient-specific, biologically-guided radiation therapy (RT) plans and to quantify and predict response to RT in glioblastoma. We investigate the biological correlates and imaging physics driving T2-MRI based response to radiation therapy using an MRI simulator. Methods: We have integrated a patient-specific biomathematical model of glioblastoma proliferation, invasion and radiotherapy with a multiobjective evolutionary algorithm for intensity-modulated RT optimization to construct individualized, biologically-guided plans. Patient-individualized simulations of the standard-of-care and optimized plans are compared in terms of several biological metrics quantified on MRI. An extension of the PI model is used to investigate the role of angiogenesis and its correlates in glioma response to therapy with the Proliferation-Invasion-Hypoxia- Necrosis-Angiogenesis model (PIHNA). The PIHNA model is used with a brain tissue phantom to predict tumor-induced vasogenic edema, tumor and tissue density that is used in a multi-compartmental MRI signal equation for generation of simulated T2- weighted MRIs. Results: Applying a novel metric of treatment response (Days Gained) to the patient-individualized simulation results predicted that the optimized RT plans would have a significant impact on delaying tumor progression, with Days Gained increases from 21% to 105%. For the T2- MRI simulations, initial validation tests compared average simulated T2 values for white matter, tumor, and peripheral edema to values cited in the literature. Simulated results closely match the characteristic T2 value for each tissue. Conclusion: Patient-individualized simulations using the combination of a biomathematical model with an optimization algorithm for RT generated biologically-guided doses that decreased normal tissue dose and increased therapeutic ratio with the potential to improve survival outcomes for treatment of glioblastoma. Simulated T2-MRI

  3. A data transmission method for particle physics experiments based on Ethernet physical layer

    Science.gov (United States)

    Huang, Xi-Ru; Cao, Ping; Zheng, Jia-Jun

    2015-11-01

    Due to its advantages of universality, flexibility and high performance, fast Ethernet is widely used in readout system design for modern particle physics experiments. However, Ethernet is usually used together with the TCP/IP protocol stack, which makes it difficult to implement readout systems because designers have to use the operating system to process this protocol. Furthermore, TCP/IP degrades the transmission efficiency and real-time performance. To maximize the performance of Ethernet in physics experiment applications, a data readout method based on the physical layer (PHY) is proposed. In this method, TCP/IP is replaced with a customized and simple protocol, which makes it easier to implement. On each readout module, data from the front-end electronics is first fed into an FPGA for protocol processing and then sent out to a PHY chip controlled by this FPGA for transmission. This kind of data path is fully implemented by hardware. From the side of the data acquisition system (DAQ), however, the absence of a standard protocol causes problems for the network related applications. To solve this problem, in the operating system kernel space, data received by the network interface card is redirected from the traditional flow to a specified memory space by a customized program. This memory space can easily be accessed by applications in user space. For the purpose of verification, a prototype system has been designed and implemented. Preliminary test results show that this method can meet the requirements of data transmission from the readout module to the DAQ with an efficient and simple manner. Supported by National Natural Science Foundation of China (11005107) and Independent Projects of State Key Laboratory of Particle Detection and Electronics (201301)

  4. Implementation of statistical analysis methods for medical physics data; Implementacao de metodos de analise estatistica para dados de fisica medica

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Marilia S.; Pinto, Nivia G.P.; Barroso, Regina C.; Oliveira, Luis F., E-mail: mariliasilvat@gmail.co, E-mail: lfolive@oi.com.b, E-mail: cely_barroso@hotmail.co, E-mail: nitatag@gmail.co [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Inst. de Fisica

    2009-07-01

    The objective of biomedical research with different radiation natures is to contribute for the understanding of the basic physics and biochemistry of the biological systems, the disease diagnostic and the development of the therapeutic techniques. The main benefits are: the cure of tumors through the therapy, the anticipated detection of diseases through the diagnostic, the using as prophylactic mean for blood transfusion, etc. Therefore, for the better understanding of the biological interactions occurring after exposure to radiation, it is necessary for the optimization of therapeutic procedures and strategies for reduction of radioinduced effects. The group pf applied physics of the Physics Institute of UERJ have been working in the characterization of biological samples (human tissues, teeth, saliva, soil, plants, sediments, air, water, organic matrixes, ceramics, fossil material, among others) using X-rays diffraction and X-ray fluorescence. The application of these techniques for measurement, analysis and interpretation of the biological tissues characteristics are experimenting considerable interest in the Medical and Environmental Physics. All quantitative data analysis must be initiated with descriptive statistic calculation (means and standard deviations) in order to obtain a previous notion on what the analysis will reveal. It is well known que o high values of standard deviation found in experimental measurements of biologicals samples can be attributed to biological factors, due to the specific characteristics of each individual (age, gender, environment, alimentary habits, etc). This work has the main objective the development of a program for the use of specific statistic methods for the optimization of experimental data an analysis. The specialized programs for this analysis are proprietary, another objective of this work is the implementation of a code which is free and can be shared by the other research groups. As the program developed since the

  5. Molecules in interstellar clouds. [physical and chemical conditions of star formation and biological evolution

    Science.gov (United States)

    Irvine, W. M.; Hjalmarson, A.; Rydbeck, O. E. H.

    1981-01-01

    The physical conditions and chemical compositions of the gas in interstellar clouds are reviewed in light of the importance of interstellar clouds for star formation and the origin of life. The Orion A region is discussed as an example of a giant molecular cloud where massive stars are being formed, and it is pointed out that conditions in the core of the cloud, with a kinetic temperature of about 75 K and a density of 100,000-1,000,000 molecules/cu cm, may support gas phase ion-molecule chemistry. The Taurus Molecular Clouds are then considered as examples of cold, dark, relatively dense interstellar clouds which may be the birthplaces of solar-type stars and which have been found to contain the heaviest interstellar molecules yet discovered. The molecular species identified in each of these regions are tabulated, including such building blocks of biological monomers as H2O, NH3, H2CO, CO, H2S, CH3CN and H2, and more complex species such as HCOOCH3 and CH3CH2CN.

  6. Scales and scaling in turbulent ocean sciences; physics-biology coupling

    Science.gov (United States)

    Schmitt, Francois

    2015-04-01

    Geophysical fields possess huge fluctuations over many spatial and temporal scales. In the ocean, such property at smaller scales is closely linked to marine turbulence. The velocity field is varying from large scales to the Kolmogorov scale (mm) and scalar fields from large scales to the Batchelor scale, which is often much smaller. As a consequence, it is not always simple to determine at which scale a process should be considered. The scale question is hence fundamental in marine sciences, especially when dealing with physics-biology coupling. For example, marine dynamical models have typically a grid size of hundred meters or more, which is more than 105 times larger than the smallest turbulence scales (Kolmogorov scale). Such scale is fine for the dynamics of a whale (around 100 m) but for a fish larvae (1 cm) or a copepod (1 mm) a description at smaller scales is needed, due to the nonlinear nature of turbulence. The same is verified also for biogeochemical fields such as passive and actives tracers (oxygen, fluorescence, nutrients, pH, turbidity, temperature, salinity...) In this framework, we will discuss the scale problem in turbulence modeling in the ocean, and the relation of Kolmogorov's and Batchelor's scales of turbulence in the ocean, with the size of marine animals. We will also consider scaling laws for organism-particle Reynolds numbers (from whales to bacteria), and possible scaling laws for organism's accelerations.

  7. Biological and physical contributions to the accumulation of strombid gastropods in a Pliocene shell bed

    Energy Technology Data Exchange (ETDEWEB)

    Geary, D.H. (Univ. of Wisconsin, Madison (USA)); Allmon, W.D. (Univ. of South Florida, Tampa (USA))

    1990-06-01

    Before the evolutionary and ecological information contained in shell beds can be interpreted, the conditions of shell bed formation must be understood. Here the authors investigate the mode and time scale of accumulation of a dense layer of Strombus floridanus in the Pliocene Pinecrest Beds of Florida. They utilize a variety of comparative taphonomic data, including the extent of encrustation and boring on strombid shells of different ontogenetic ages, and on accompanying pelecypods of different ecological types. The taphonomic comparisons enable them to reconstruct more accurately the events of shell bed formation. The formation of the strombid shell layer involved both biological and physical components. The characteristically gregarious behavior of Strombus is reflected in the large number of individuals preserved in this layer. Based on average densities of individuals in strombid colonies today, the authors estimate that a time period of tens to hundreds of years was required to accumulate these fossils. Repeated sediment winnowing by storms, followed by rapid reburial in a regime of at least episodically high sedimentation rates, is the most likely mechanism of accumulation, and accounts for the observed patterns of encrustation and boring on the shells of Strombus and various associated pelecypods. The origin of Florida's Plio-Pleistocene shelly sands is poorly understood; analysis of this bed may provide a working model for future taphonomic studies.

  8. Climate change and physical disturbance manipulations result in distinct biological soil crust communities.

    Science.gov (United States)

    Steven, Blaire; Kuske, Cheryl R; Gallegos-Graves, La Verne; Reed, Sasha C; Belnap, Jayne

    2015-11-01

    Biological soil crusts (biocrusts) colonize plant interspaces in many drylands and are critical to soil nutrient cycling. Multiple climate change and land use factors have been shown to detrimentally impact biocrusts on a macroscopic (i.e., visual) scale. However, the impact of these perturbations on the bacterial components of the biocrusts remains poorly understood. We employed multiple long-term field experiments to assess the impacts of chronic physical (foot trampling) and climatic changes (2°C soil warming, altered summer precipitation [wetting], and combined warming and wetting) on biocrust bacterial biomass, composition, and metabolic profile. The biocrust bacterial communities adopted distinct states based on the mechanism of disturbance. Chronic trampling decreased biomass and caused small community compositional changes. Soil warming had little effect on biocrust biomass or composition, while wetting resulted in an increase in the cyanobacterial biomass and altered bacterial composition. Warming combined with wetting dramatically altered bacterial composition and decreased Cyanobacteria abundance. Shotgun metagenomic sequencing identified four functional gene categories that differed in relative abundance among the manipulations, suggesting that climate and land use changes affected soil bacterial functional potential. This study illustrates that different types of biocrust disturbance damage biocrusts in macroscopically similar ways, but they differentially impact the resident soil bacterial communities, and the communities' functional profiles can differ depending on the disturbance type. Therefore, the nature of the perturbation and the microbial response are important considerations for management and restoration of drylands. PMID:26276111

  9. A Study of Motivation and Other Factors as Relating to Course Achievement in Introductory College Biology, Chemistry, and Physics.

    Science.gov (United States)

    Pridmore, Brooke M.; Halyard, Rebecca A.

    Results of a preliminary study that examined various factors relating to achievement in introductory level biology, chemistry, and physics classes at a public junior college are presented. Background variables, including age, sex, college major, grade point average, SAT-Verbal and SAT-Quantitative, and the sixteen-part scores of Academic…

  10. Practical Work in Biology, Chemistry and Physics at Lower Secondary and General Upper Secondary Schools in Slovenia

    Science.gov (United States)

    Sorgo, Andrej; Spernjak, Andreja

    2012-01-01

    Syllabi in the science subjects, biology, chemistry and physics at lower and general upper secondary school are compared in the light of their underlying philosophies, goals, objectives and recognized importance in science teaching. Even though all syllabi were prepared within the same framework, great differences among syllabi concerning…

  11. Physical methods for seed vigourization: advantages and challenges in seed technology

    Directory of Open Access Journals (Sweden)

    Susana eAraújo

    2016-05-01

    Full Text Available In the context of seed technology, the use of physical methods for increasing plant production offers advantages over conventional treatments based on chemical substances. The effects of physical vigourization treatments in seeds can be now addressed at multiple levels, ranging from morpho-structural aspects to changes in gene expression and protein or metabolite accumulation. Among the physical methods available, magneto-priming and irradiation with microwaves or ionizing radiations are the most promissory pre-sowing seed treatments. Magneto-priming is based on the application of magnetic fields and described as an eco-friendly, cheap, non-invasive technique with proved beneficial effects on seed germination, vigour and crop yield. Ionizing radiations, as gamma-rays and X-rays, have been widely regarded as a powerful tool in agricultural sciences and food technology. Gamma-rays delivered at low dose have showed to enhance germination percentage and seedling establishment, acting as an actual ‘priming’ treatment. Different biological effects have been observed in seeds subjected to microwaves and X-rays but knowledge about their impact as seed vigourization agent or stimulatory effects on germination need to be further extended. Ultraviolet (UV radiations, namely UV-A and UV-C have shown to stimulate positive impacts on seed health, germination and seedling vigour. For all mentioned physical treatments, extensive fundamental and applied research is still needed to define the optimal dose, exposition time, genotype- and environment-dependent irradiation conditions. Electron paramagnetic resonance (EPR has an enormous potential in seed technology not fully explored to monitor seed vigourization treatments and/or identifying the best suitable irradiation dose or time-point to stop the treatment. The present manuscript describes the use of physical methods for seed vigourization, while providing a critical discussion on the constraints and

  12. Physical Methods for Seed Invigoration: Advantages and Challenges in Seed Technology.

    Science.gov (United States)

    Araújo, Susana de Sousa; Paparella, Stefania; Dondi, Daniele; Bentivoglio, Antonio; Carbonera, Daniela; Balestrazzi, Alma

    2016-01-01

    In the context of seed technology, the use of physical methods for increasing plant production offers advantages over conventional treatments based on chemical substances. The effects of physical invigoration treatments in seeds can be now addressed at multiple levels, ranging from morpho-structural aspects to changes in gene expression and protein or metabolite accumulation. Among the physical methods available, "magneto-priming" and irradiation with microwaves (MWs) or ionizing radiations (IRs) are the most promising pre-sowing seed treatments. "Magneto-priming" is based on the application of magnetic fields and described as an eco-friendly, cheap, non-invasive technique with proved beneficial effects on seed germination, vigor and crop yield. IRs, as γ-rays and X-rays, have been widely regarded as a powerful tool in agricultural sciences and food technology. Gamma-rays delivered at low dose have showed to enhance germination percentage and seedling establishment, acting as an actual 'priming' treatment. Different biological effects have been observed in seeds subjected to MWs and X-rays but knowledge about their impact as seed invigoration agent or stimulatory effects on germination need to be further extended. Ultraviolet (UV) radiations, namely UV-A and UV-C have shown to stimulate positive impacts on seed health, germination, and seedling vigor. For all mentioned physical treatments, extensive fundamental and applied research is still needed to define the optimal dose, exposition time, genotype- and environment-dependent irradiation conditions. Electron paramagnetic resonance has an enormous potential in seed technology not fully explored to monitor seed invigoration treatments and/or identifying the best suitable irradiation dose or time-point to stop the treatment. The present manuscript describes the use of physical methods for seed invigoration, while providing a critical discussion on the constraints and advantages. The future perspectives related to

  13. Through Microgravity and Towards the Stars: Microgravity and Strategic Research at Marshall's Biological and Physical Space Research Laboratory

    Science.gov (United States)

    Curreri, Peter A.

    2003-01-01

    The Microgravity and Strategic research at Marshall s Biological and Physical Space Research Laboratory will be reviewed. The environment in orbit provides a unique opportunity to study Materials Science and Biotechnology in the absence of sedimentation and convection. There are a number of peer-selected investigations that have been selected to fly on the Space Station that have been conceived and are led by Marshall s Biological and Physical Research Laboratory s scientists. In addition to Microgravity research the Station will enable research in "Strategic" Research Areas that focus on enabling humans to live, work, and explore the solar system safely. New research in Radiation Protection, Strategic Molecular Biology, and In-Space Fabrication will be introduced.

  14. High throughput instruments, methods, and informatics for systems biology.

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, Michael B.; Cowie, Jim R. (New Mexico State University, Las Cruces, NM); Van Benthem, Mark Hilary; Wylie, Brian Neil; Davidson, George S.; Haaland, David Michael; Timlin, Jerilyn Ann; Aragon, Anthony D. (University of New Mexico, Albuquerque, NM); Keenan, Michael Robert; Boyack, Kevin W.; Thomas, Edward Victor; Werner-Washburne, Margaret C. (University of New Mexico, Albuquerque, NM); Mosquera-Caro, Monica P. (University of New Mexico, Albuquerque, NM); Martinez, M. Juanita (University of New Mexico, Albuquerque, NM); Martin, Shawn Bryan; Willman, Cheryl L. (University of New Mexico, Albuquerque, NM)

    2003-12-01

    High throughput instruments and analysis techniques are required in order to make good use of the genomic sequences that have recently become available for many species, including humans. These instruments and methods must work with tens of thousands of genes simultaneously, and must be able to identify the small subsets of those genes that are implicated in the observed phenotypes, or, for instance, in responses to therapies. Microarrays represent one such high throughput method, which continue to find increasingly broad application. This project has improved microarray technology in several important areas. First, we developed the hyperspectral scanner, which has discovered and diagnosed numerous flaws in techniques broadly employed by microarray researchers. Second, we used a series of statistically designed experiments to identify and correct errors in our microarray data to dramatically improve the accuracy, precision, and repeatability of the microarray gene expression data. Third, our research developed new informatics techniques to identify genes with significantly different expression levels. Finally, natural language processing techniques were applied to improve our ability to make use of online literature annotating the important genes. In combination, this research has improved the reliability and precision of laboratory methods and instruments, while also enabling substantially faster analysis and discovery.

  15. Signal processing for molecular and cellular biological physics: an emerging field

    Science.gov (United States)

    Little, Max A.; Jones, Nick S.

    2013-01-01

    Recent advances in our ability to watch the molecular and cellular processes of life in action—such as atomic force microscopy, optical tweezers and Forster fluorescence resonance energy transfer—raise challenges for digital signal processing (DSP) of the resulting experimental data. This article explores the unique properties of such biophysical time series that set them apart from other signals, such as the prevalence of abrupt jumps and steps, multi-modal distributions and autocorrelated noise. It exposes the problems with classical linear DSP algorithms applied to this kind of data, and describes new nonlinear and non-Gaussian algorithms that are able to extract information that is of direct relevance to biological physicists. It is argued that these new methods applied in this context typify the nascent field of biophysical DSP. Practical experimental examples are supplied. PMID:23277603

  16. Glutarimides: Biological activity, general synthetic methods and physicochemical properties

    Directory of Open Access Journals (Sweden)

    Popović-Đorđević Jelena B.

    2015-01-01

    Full Text Available Glutarimides, 2,6-dioxopiperidines are compounds that rarely occur in natural sources, but so far isolated ones exert widespread pharmacological activities, which makes them valuable as potential pharmacotherapeutics. Glutarimides act as androgen receptor antagonists, anti-inflammatory, anxiolytics, antibacterials, and tumor suppressing agents. Some synthetic glutarimide derivatives are already in use as immunosuppressive and sedative (e.g., thalidomide or anxiolytics (buspirone drugs. The wide applicability of this class of compounds, justify the interest of scientists to explore new pathways for its syntheses. General methods for synthesis of six-membered imide ring, are presented in this paper. These methods include: a reaction of dicarboxylic acids with ammonia or primary amine, b reactions of cyclization: amido-acids, diamides, dinitriles, nitrilo-acids, amido-nitriles, amido-esters, amidoacyl-chlorides or diacyl-chlorides, c adition of carbon-monoxide on a,b-unsaturated amides, d oxidation reactions, e Michael adition of active methylen compounds on methacrylamide or conjugated amides. Some of the described methods are used for closing glutarimide ring in syntheses of farmacological active compounds sesbanimide and aldose reductase inhibitors (ARI. Analyses of the geometry, as well as, the spectroscopic analyses (NMR and FT-IR of some glutarimides are presented because of their broad spectrum of pharmacological activity. To elucidate structures of glutarimides, geometrical parameters of newly synthesized tert-pentyl-1-benzyl-4-methyl-glutarimide-3-carboxylate (PBMG are analyzed and compared with the experimental data from X-ray analysis for glutarimide. Moreover, molecular electrostatic potential (MEP surface which is plotted over the optimized geometry to elucidate the reactivity of PBMG molecule is analyzed. The electronic properties of glutarimide derivatives are explained on the example of thalidomide. The Frontier Molecular Orbital

  17. Optimization and validation of spectrophotometric methods for determination of finasteride in dosage and biological forms

    OpenAIRE

    Amin, Alaa S.; Kassem, Mohammed A.

    2012-01-01

    Aim and Background: Three simple, accurate and sensitive spectrophotometric methods for the determination of finasteride in pure, dosage and biological forms, and in the presence of its oxidative degradates were developed. Materials and Methods: These methods are indirect, involve the addition of excess oxidant potassium permanganate for method A; cerric sulfate [Ce(SO4)2] for methods B; and N-bromosuccinimide (NBS) for method C of known concentration in acid medium to finasteride, and the de...

  18. Multilayer physical system and biological structure in the upper water of Lake Biwa during summer

    Science.gov (United States)

    Homma, H.; Yamazaki, H.; Nagai, T.; Doubell, M.; Amakasu, K.; Kumagai, M.; Jiao, C.; Ishikawa, T.

    2010-12-01

    Lake Biwa is the largest lake in Japan and supplies water for over ten million people. Observations were made over 24-hour at a station in North Basin of Lake Biwa in summer 2008 and 2009 to detect events in relation to oxygen transport. We deployed a free-fall microstructure profiler, TurboMAP-L, to measure mixing intensity and fluorescence, and basic hydrographic structure. An F-probe (Fine-scale profiler) was also deployed to measure dissolved oxygen. During the 2008 survey we also deployed TAPS (Tracor acoustic profiling system) to detect zooplankton distribution. For 2009 LISST-100X (Laser in-situ scattering and transmissiometry), was deployed only during the night to measure particle size spectra. For both the 2008 and 2009 surveys the water column showed similar structure. The thermocline was observed between 10 to 20 m depth throughout the day and formed sharp density gradient. The buoyancy frequency, N2, for the thermocline exceeded 10-3 s-2 (Fig.1). Active mixing layers were observed above the thermocline and also beneath it, where the rate of turbulent kinetic energy dissipation, ɛ, was around 10-7 W kg-1. While, mixing intensity in stratified layer was quite weak, ɛ didn’t exceed 10-8 W kg-1 (Fig.2). Eddy diffusivity coefficient, Kρ, in this stratified and weakly turbulent layer was estimated to be on the order of 10-7 m2 s-1, which is almost equivalent to a molecular diffusion level. Thus, the strongly stratified and weakly turbulent thermocline acted as a barrier to prevent oxygen transport from the surface to the lower layer. Additionally, the chlorophyll maximum and peak in zooplankton abundance occurred in the thermocline (Fig.1). We will present multilayer biological structure around a strong thermocline that indicates a complicated interaction between physical and biological process. Fig.1 Distribution of log10 of buoyancy frequency squared (gray scale) and chlorophyll (white contours; thicker line indicates higher value) Fig.2 Distribution

  19. Biological effects and physics of solar and galactic cosmic radiation, Part B; Proceedings of a NATO Advanced Study Institute on Biological Effects and Physics of Solar and Galactic Cosmic Radiation, Algarve, Portugal, Oct. 13-23, 1991

    Science.gov (United States)

    Swenberg, Charles E. (Editor); Horneck, Gerda (Editor); Stassinopoulos, E. G. (Editor)

    1993-01-01

    Since there is an increasing interest in establishing lunar bases and exploring Mars by manned missions, it is important to develop appropriate risk estimates and radiation protection guidelines. The biological effects and physics of solar and galactic cosmic radiation are examined with respect to the following: the radiation environment of interplanetary space, the biological responses to radiation in space, and the risk estimates for deep space missions. There is a need for a long-term program where ground-based studies can be augmented by flight experiments and an international standardization with respect to data collection, protocol comparison, and formulation of guidelines for future missions.

  20. Research on Catalytic Properties of Palladium Catalyst Prepared by Biological Reduction Method

    Institute of Scientific and Technical Information of China (English)

    Zhang Feng; Fu Jiquan

    2013-01-01

    This paper relates to highly dispersed supported Pd/MWCNTs and Pd/α-Al2O3 catalysts prepared by biological reduction method. The physico-chemical properties and the difference in catalytic activity of Pd catalysts prepared by bio-logical reduction method and chemical method, respectively, were investigated using XRD, TEM and speciifc surface char-acterization methods. The catalytic properties of catalysts were studied through activity evaluation means. The test results showed that the catalysts prepared by biological method were characteristic of small Pd nanoparticle size, good dispersion and low agglomeration, while possessing a high activity and stability in styrene hydrogenation reaction in comparison with catalysts prepared via the chemical method.

  1. Nitrate biosensors and biological methods for nitrate determination.

    Science.gov (United States)

    Sohail, Manzar; Adeloju, Samuel B

    2016-06-01

    The inorganic nitrate (NO3‾) anion is present under a variety of both natural and artificial environmental conditions. Nitrate is ubiquitous within the environment, food, industrial and physiological systems and is mostly present as hydrated anion of a corresponding dissolved salt. Due to the significant environmental and toxicological effects of nitrate, its determination and monitoring in environmental and industrial waters are often necessary. A wide range of analytical techniques are available for nitrate determination in various sample matrices. This review discusses biosensors available for nitrate determination using the enzyme nitrate reductase (NaR). We conclude that nitrate determination using biosensors is an excellent non-toxic alternative to all other available analytical methods. Over the last fifteen years biosensing technology for nitrate analysis has progressed very well, however, there is a need to expedite the development of nitrate biosensors as a suitable alternative to non-enzymatic techniques through the use of different polymers, nanostructures, mediators and strategies to overcome oxygen interference. PMID:27130094

  2. Apparatus and method for biological purification of waste

    Science.gov (United States)

    Lucido, John A.; Keenan, Daniel; Premuzic, Eugene T.; Lin, Mow S.; Shelenkova, Ludmila

    1998-11-24

    An apparatus is disclosed for containing a microorganism culture in an active exponential growth and delivering a supply of microorganisms to an environment containing wastes for bio-augmenting the biodegradation of the wastes. The apparatus comprises a bioreactor and an operably connected controller. The bioreactor has a bioreactor chamber for containing a supply of microorganisms, a second chamber for containing a supply of water and inorganic nutrients, and a third chamber for containing a supply of organic nutrients. The bioreactor is operably connected to the controller in which a first pump is operably connected in fluid communication between the bioreactor chamber and the second chamber and third chamber, and a second pump is operably connected in fluid communication between the bioreactor chamber and the environment containing wastes to be biodegraded. The controller further includes a timer and regulator operably connected to the first and second pumps to effectively maintain the microorganisms in exponential growth in the bioreactor chamber and to deliver microorganisms to an environment to be treated. Also, disclosed is a method for bio-augmenting the biodegradation of wastes.

  3. ELECTRO PHYSICAL METHODS AND DEVICES OF ELECTRO TECHNOLOGICAL FARM COMPLEX IN THE KUBAN REGION

    Directory of Open Access Journals (Sweden)

    Kurzin N. N.

    2015-10-01

    Full Text Available The absence of theoretical bases for interaction of the magnetic field and cellular mechanism, the lack of an effective way to determining the results of this action has led to the creation of a large number of machines and devices of electromagnetic influence on biological objects of vegetable and animal origin. Many of them are contain special generators and inductors developed for a specific type of object. By means of these constructions, used in electro technological processes at agricultural companies of the Kuban region, we increase productivity of different crops, increase productivity of animals and poultry, change the physical and chemical properties of liquids and solutions, conducted in boiler water preparation. A distinctive feature of the electromagnetic field processing of objects of biological origin is sufficiently high efficiency of outcomes at insignificant energy costs. All this foreshadows further improve the long-term development and research in this area. By analyzing the existing devices, it can be concluded, that all of presently available designs for electromagnetic treatment are classified by a common attribute - a method for creating a magnetic field. The lack of reliable, logically complete theory of influence of electromagnetic influence on biological systems agricultural purpose and the availability of practical recommendations when to use inductors working on constant, and when the AC has led to the fact that to obtain the necessary effect, share the same devices have become connected to various sources of supply

  4. Tree species traits influence soil physical, chemical, and biological properties in high elevation forests.

    Directory of Open Access Journals (Sweden)

    Edward Ayres

    Full Text Available BACKGROUND: Previous studies have shown that plants often have species-specific effects on soil properties. In high elevation forests in the Southern Rocky Mountains, North America, areas that are dominated by a single tree species are often adjacent to areas dominated by another tree species. Here, we assessed soil properties beneath adjacent stands of trembling aspen, lodgepole pine, and Engelmann spruce, which are dominant tree species in this region and are distributed widely in North America. We hypothesized that soil properties would differ among stands dominated by different tree species and expected that aspen stands would have higher soil temperatures due to their open structure, which, combined with higher quality litter, would result in increased soil respiration rates, nitrogen availability, and microbial biomass, and differences in soil faunal community composition. METHODOLOGY/PRINCIPAL FINDINGS: We assessed soil physical, chemical, and biological properties at four sites where stands of aspen, pine, and spruce occurred in close proximity to one-another in the San Juan Mountains, Colorado. Leaf litter quality differed among the tree species, with the highest nitrogen (N concentration and lowest lignin:N in aspen litter. Nitrogen concentration was similar in pine and spruce litter, but lignin:N was highest in pine litter. Soil temperature and moisture were highest in aspen stands, which, in combination with higher litter quality, probably contributed to faster soil respiration rates from stands of aspen. Soil carbon and N content, ammonium concentration, and microbial biomass did not differ among tree species, but nitrate concentration was highest in aspen soil and lowest in spruce soil. In addition, soil fungal, bacterial, and nematode community composition and rotifer, collembolan, and mesostigmatid mite abundance differed among the tree species, while the total abundance of nematodes, tardigrades, oribatid mites, and prostigmatid

  5. Approaching complexity by stochastic methods: From biological systems to turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, Rudolf [Institute for Theoretical Physics, University of Muenster, D-48149 Muenster (Germany); Peinke, Joachim [Institute of Physics, Carl von Ossietzky University, D-26111 Oldenburg (Germany); Sahimi, Muhammad [Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-1211 (United States); Reza Rahimi Tabar, M., E-mail: mohammed.r.rahimi.tabar@uni-oldenburg.de [Department of Physics, Sharif University of Technology, Tehran 11155-9161 (Iran, Islamic Republic of); Institute of Physics, Carl von Ossietzky University, D-26111 Oldenburg (Germany); Fachbereich Physik, Universitaet Osnabrueck, Barbarastrasse 7, 49076 Osnabrueck (Germany)

    2011-09-15

    This review addresses a central question in the field of complex systems: given a fluctuating (in time or space), sequentially measured set of experimental data, how should one analyze the data, assess their underlying trends, and discover the characteristics of the fluctuations that generate the experimental traces? In recent years, significant progress has been made in addressing this question for a class of stochastic processes that can be modeled by Langevin equations, including additive as well as multiplicative fluctuations or noise. Important results have emerged from the analysis of temporal data for such diverse fields as neuroscience, cardiology, finance, economy, surface science, turbulence, seismic time series and epileptic brain dynamics, to name but a few. Furthermore, it has been recognized that a similar approach can be applied to the data that depend on a length scale, such as velocity increments in fully developed turbulent flow, or height increments that characterize rough surfaces. A basic ingredient of the approach to the analysis of fluctuating data is the presence of a Markovian property, which can be detected in real systems above a certain time or length scale. This scale is referred to as the Markov-Einstein (ME) scale, and has turned out to be a useful characteristic of complex systems. We provide a review of the operational methods that have been developed for analyzing stochastic data in time and scale. We address in detail the following issues: (i) reconstruction of stochastic evolution equations from data in terms of the Langevin equations or the corresponding Fokker-Planck equations and (ii) intermittency, cascades, and multiscale correlation functions.

  6. Test Methods for Evaluating Solid Waste, Physical/Chemical Methods. First Update. (3rd edition)

    International Nuclear Information System (INIS)

    The proposed Update is for Test Methods for Evaluating Solid Waste, Physical/Chemical Methods, SW-846, Third Edition. Attached to the report is a list of methods included in the proposed update indicating whether the method is a new method, a partially revised method, or a totally revised method. Do not discard or replace any of the current pages in the SW-846 manual until the proposed update I package is promulgated. Until promulgation of the update package, the methods in the update package are not officially part of the SW-846 manual and thus do not carry the status of EPA-approved methods. In addition to the proposed Update, six finalized methods are included for immediate inclusion into the Third Edition of SW-846. Four methods, originally proposed October 1, 1984, will be finalized in a soon to be released rulemaking. They are, however, being submitted to subscribers for the first time in the update. These methods are 7211, 7381, 7461, and 7951. Two other methods were finalized in the 2nd Edition of SW-846. They were inadvertantly omitted from the 3rd Edition and are not being proposed as new. These methods are 7081 and 7761

  7. IMOS National Reference Stations: a continental-wide physical, chemical and biological coastal observing system.

    Directory of Open Access Journals (Sweden)

    Tim P Lynch

    Full Text Available Sustained observations allow for the tracking of change in oceanography and ecosystems, however, these are rare, particularly for the Southern Hemisphere. To address this in part, the Australian Integrated Marine Observing System (IMOS implemented a network of nine National Reference Stations (NRS. The network builds on one long-term location, where monthly water sampling has been sustained since the 1940s and two others that commenced in the 1950s. In-situ continuously moored sensors and an enhanced monthly water sampling regime now collect more than 50 data streams. Building on sampling for temperature, salinity and nutrients, the network now observes dissolved oxygen, carbon, turbidity, currents, chlorophyll a and both phytoplankton and zooplankton. Additional parameters for studies of ocean acidification and bio-optics are collected at a sub-set of sites and all data is made freely and publically available. Our preliminary results demonstrate increased utility to observe extreme events, such as marine heat waves and coastal flooding; rare events, such as plankton blooms; and have, for the first time, allowed for consistent continental scale sampling and analysis of coastal zooplankton and phytoplankton communities. Independent water sampling allows for cross validation of the deployed sensors for quality control of data that now continuously tracks daily, seasonal and annual variation. The NRS will provide multi-decadal time series, against which more spatially replicated short-term studies can be referenced, models and remote sensing products validated, and improvements made to our understanding of how large-scale, long-term change and variability in the global ocean are affecting Australia's coastal seas and ecosystems. The NRS network provides an example of how a continental scaled observing systems can be developed to collect observations that integrate across physics, chemistry and biology.

  8. Nanodosimetry, the metrological tool for connecting radiation physics with radiation biology.

    Science.gov (United States)

    Grosswendt, B

    2006-01-01

    It is generally accepted that the early damage to genes or cells by ionising radiation starts with the early damage to segments of the DNA, at least, to the greater part. This damage is the result of the spatial distribution of inelastic interactions of single ionising particles within the DNA or in its neighbourhood and is, in consequence, determined by the stochastics of particle interactions in volumes a few nanometre in size. Due to the latter fact radiation damage strongly depends on radiation quality and cannot be described satisfactorily in detail by macroscopic quantities like absorbed dose or linear energy transfer (LET). It can, however, be described approximately by the probability distribution of ionisation cluster-size formation in nanometric target volumes of liquid water (nanodosimetry). One aim of nanodosimetry is, therefore, to measure the radiation induced frequency distribution of ionisation cluster-size formation in liquid water, as a substitute for sub-cellular material, in volumes which are comparable in size with those of the most probable radio-sensitive volumes of biological systems. After a short description of the main aspects of cluster-size formation by ionising particles, an overview is given about the measuring principles applied in present-day nanodosimetric measurements. Afterwards, physical principles are discussed which can be used to convert ionisation cluster-size distributions measured in gases into those caused by ionising radiation in liquid water. In a final section, the probability distribution of ionisation cluster-size formation in liquid water is discussed from the point of view of damage formation to segments of the DNA. PMID:17169948

  9. Seasonal nutrient and plankton dynamics in a physical-biological model of Crater Lake

    Science.gov (United States)

    Fennel, K.; Collier, R.; Larson, G.; Crawford, G.; Boss, E.

    2007-01-01

    A coupled 1D physical-biological model of Crater Lake is presented. The model simulates the seasonal evolution of two functional phytoplankton groups, total chlorophyll, and zooplankton in good quantitative agreement with observations from a 10-year monitoring study. During the stratified period in summer and early fall the model displays a marked vertical structure: the phytoplankton biomass of the functional group 1, which represents diatoms and dinoflagellates, has its highest concentration in the upper 40 m; the phytoplankton biomass of group 2, which represents chlorophyta, chrysophyta, cryptomonads and cyanobacteria, has its highest concentrations between 50 and 80 m, and phytoplankton chlorophyll has its maximum at 120 m depth. A similar vertical structure is a reoccurring feature in the available data. In the model the key process allowing a vertical separation between biomass and chlorophyll is photoacclimation. Vertical light attenuation (i.e., water clarity) and the physiological ability of phytoplankton to increase their cellular chlorophyll-to-biomass ratio are ultimately determining the location of the chlorophyll maximum. The location of the particle maxima on the other hand is determined by the balance between growth and losses and occurs where growth and losses equal. The vertical particle flux simulated by our model agrees well with flux measurements from a sediment trap. This motivated us to revisit a previously published study by Dymond et al. (1996). Dymond et al. used a box model to estimate the vertical particle flux and found a discrepancy by a factor 2.5-10 between their model-derived flux and measured fluxes from a sediment trap. Their box model neglected the exchange flux of dissolved and suspended organic matter, which, as our model and available data suggests is significant for the vertical exchange of nitrogen. Adjustment of Dymond et al.'s assumptions to account for dissolved and suspended nitrogen yields a flux estimate that is

  10. Methods for collection and analysis of aquatic biological and microbiological samples

    Science.gov (United States)

    Britton, L.J.; Greeson, P.E.

    1988-01-01

    Chapter A4, methods for collection and analyses of aquatic biological and microbiological samples, contains methods used by the U.S. Geological Survey to collect, preserve, and analyze waters to determine their biological and microbiological properties. Part 1 consists of detailed descriptions of more than 45 individual methods, including those for bacteria, phytoplankton, zooplankton, seston, periphyton, macrophytes, benthic invertebrates, fish and other vertebrates, cellular contents, productivity and bioassay. Each method is summarized, and the applications, interferences, apparatus, reagents, analyses, calculations, reporting of results, precisions, and references are given. Part 2 consists of a glossary. Part 3 is a list of taxonomic references. (USGS)

  11. A supplement to "Methods for collection and analysis of aquatic biological and microbiological samples"

    Science.gov (United States)

    1979-01-01

    The report contains methods used by the U.S. Geological Survey to collect, preserve, and analyze waters to determine their biological and microbiological properties. It supplements, "Methods for Collection and Analysis of Aquatic Biological and Microbiological Samples" (TWRI, Book 5, Chapter A4, 1977, edited by P. E. Greeson, T. A. Ehlke, G. A. Irwin, B. W. Lium, and K. V. Slack). Included in the supplement are 5 new methods, a new section of selected taxonomic references for Ostracoda, and 6 revised methods.

  12. Electron spin interactions in chemistry and biology fundamentals, methods, reactions mechanisms, magnetic phenomena, structure investigation

    CERN Document Server

    Likhtenshtein, Gertz

    2016-01-01

    This book presents the versatile and pivotal role of electron spin interactions in nature. It provides the background, methodologies and tools for basic areas related to spin interactions, such as spin chemistry and biology, electron transfer, light energy conversion, photochemistry, radical reactions, magneto-chemistry and magneto-biology. The book also includes an overview of designing advanced magnetic materials, optical and spintronic devices and photo catalysts. This monograph appeals to scientists and graduate students working in the areas related to spin interactions physics, biophysics, chemistry and chemical engineering.

  13. Top Quark Physics at the ILC: Methods and Meanings

    OpenAIRE

    Sullivan, Zack

    2009-01-01

    The physics case for studying top-quark physics at the International Linear Collider is well established. This summary places in context the top-quark physics goals, examines the current state-of-the art in understanding of the top-quark mass, and identifies some areas in which the study of the top-quark mass enhances our understanding of new techniques.

  14. Physical and biological pretreatment quality assurance of the head and neck cancer plan with the volumetric modulated arc therapy

    Science.gov (United States)

    Park, So-Hyun; Lee, Dong-Soo; Lee, Yun-Hee; Lee, Seu-Ran; Kim, Min-Ju; Suh, Tae-Suk

    2015-09-01

    The aim of this work is to demonstrate both the physical and the biological quality assurance (QA) aspects as pretreatment QA of the head and neck (H&N) cancer plan for the volumetric modulated arc therapy (VMAT). Ten H&N plans were studied. The COMPASS® dosimetry analysis system and the tumor control probability (TCP) and the normal tissue complication probability (NTCP) calculation free program were used as the respective measurement and calculation tools. The reliability of these tools was verified by a benchmark study in accordance with the TG-166 report. For the physical component of QA, the gamma passing rates and the false negative cases between the calculated and the measured data were evaluated. The biological component of QA was performed based on the equivalent uniform dose (EUD), TCP and NTCP values. The evaluation was performed for the planning target volumes (PTVs) and the organs at risks (OARs), including the eyes, the lens, the parotid glands, the esophagus, the spinal cord, and the brainstem. All cases had gamma passing rates above 95% at an acceptance tolerance level with the 3%/3 mm criteria. In addition, the false negative instances were presented for the PTVs and OARs. The gamma passing rates exhibited a weak correlation with false negative cases. For the biological QA, the physical dose errors affect the EUD and the TCP for the PTVs, but no linear correlation existed between them. The EUD and NTCP for the OARs were shown the random differences that could not be attributed to the dose errors from the physical QA. The differences in the EUD and NTCP between the calculated and the measured results were mainly demonstrated for the parotid glands. This study describes the importance and the necessity of improved QA to accompany both the physical and the biological aspects for accurate radiation treatment.

  15. Thermodynamics, Gibbs Method and Statistical Physics of Electron Gases Gibbs Method and Statistical Physics of Electron Gases

    CERN Document Server

    Askerov, Bahram M

    2010-01-01

    This book deals with theoretical thermodynamics and the statistical physics of electron and particle gases. While treating the laws of thermodynamics from both classical and quantum theoretical viewpoints, it posits that the basis of the statistical theory of macroscopic properties of a system is the microcanonical distribution of isolated systems, from which all canonical distributions stem. To calculate the free energy, the Gibbs method is applied to ideal and non-ideal gases, and also to a crystalline solid. Considerable attention is paid to the Fermi-Dirac and Bose-Einstein quantum statistics and its application to different quantum gases, and electron gas in both metals and semiconductors is considered in a nonequilibrium state. A separate chapter treats the statistical theory of thermodynamic properties of an electron gas in a quantizing magnetic field.

  16. Biological Maturation, Body Morphology and Physical Performance in 8–16 year-old obese girls from Montes Claros – MG

    Science.gov (United States)

    Freitas, Alex S.; Figueiredo, António J.B.; de Freitas, Andréia L.R.; Rodrigues, Vinícius D.; da Cunha, Alexandre A.C.; Deusdará, Fernando F.; Coelho e Silva, Manuel J.

    2014-01-01

    Measurements of maturity depend on the biological system considered since differences are often found in performance and body size in subjects of the same chronological age. The objective of this study was to identify associations between biological maturation, body morphology and physical performance in girls aged from 8.0 to 15.9 year-old and to verify the bone age in obese girls and compare it with chronological age. For that purpose 2040 (11.9 ± 2.3 years) school girls from Montes Claros, participated in this study. Regular anthropometric measures as height and body mass were taken. Triceps, biceps, subscapular, abdominal, suprailiac and calf skinfolds were also registered. Physical performance was assessed trough the test of a standing long jump, handgrip strength and 20 m multistage shuttle run. Maturational status, the average age at menarche and identification of PHV (maturity off set) were determined by means of the retrospective method. Girls with the BMI above the 95th percentile got their bone age evaluated through X-ray of the left hand/wrist, in accordance with the FELS method. It was possible to find an average age at menarche of 11.30 ± 0.70, while the average age at PHV was 12.17 ± 0.71 years of age. It was observed that both body composition and physical performance showed a tendency to increase with advancing age. However, when controlling the effect of maturation, despite having higher values in body composition the post-menarche girls group did not show higher levels of physical performance. In all age groups, obese girls showed mean rates of bone age higher than chronologic age (12.25 ± 2.09 and 14.09 ± 2.35, respectively, p=0.000). Chronological age should be used with caution when evaluating obese teenagers as it may underestimate biological age. PMID:25713657

  17. Method And System For Examining Biological Materials Using Low Power Cw Excitation Raman Spectroscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Alfano, Robert R. (Bronx, NY); Wang, Wubao (Flushing, NY)

    2003-05-06

    A method and system for examining biological materials using low-power cw excitation Raman spectroscopy. A low-power continuous wave (cw) pump laser beam and a low-power cw Stokes (or anti-Stokes) probe laser beam simultaneously illuminate a biological material and traverse the biological material in collinearity. The pump beam, whose frequency is varied, is used to induce Raman emission from the biological material. The intensity of the probe beam, whose frequency is kept constant, is monitored as it leaves the biological material. When the difference between the pump and probe excitation frequencies is equal to a Raman vibrational mode frequency of the biological material, the weak probe signal becomes amplified by one or more orders of magnitude (typically up to about 10.sup.4 -10.sup.6) due to the Raman emission from the pump beam. In this manner, by monitoring the intensity of the probe beam emitted from the biological material as the pump beam is varied in frequency, one can obtain an excitation Raman spectrum for the biological material tested. The present invention may be applied to in the in vivo and/or in vitro diagnosis of diabetes, heart disease, hepatitis, cancers and other diseases by measuring the characteristic excitation Raman lines of blood glucose, cholesterol, serum glutamic oxalacetic transaminase (SGOT)/serum glutamic pyruvic transaminase (SGPT), tissues and other corresponding Raman-active body constituents, respectively.

  18. PROTEIN QUALITY EVALUATION OF NAKED OAT (AVENA NUDA L. AND BUCKWHEAT (FAGOPYRUM ESCULENTUM MOENCH BY BIOLOGICAL METHODS AND PDCAAS METHOD

    Directory of Open Access Journals (Sweden)

    Martina Vršková

    2013-02-01

    Full Text Available The aim of this paper was to determine the protein quality of naked oat (Avena nuda L. and buckwheat (Fagopyrum esculentum Moench by traditional biological methods [Protein Efficiency Ratio (PER, Net Protein Utilization (NPU, Biological value] and the protein digestibility-corrected amino acid score (PDCAAS. As an animal model we used growing rats at the age of 21 days and at average body weight 83 g. The tested feeds represented the only nitrogen source in the experimental diets, and the tested nitrogen substances were 10 % of the feed ration in dry matter. We found higher values achieved in growth, feed conversion and crude protein intake in the group fed buckwheat. Buckwheat achieved higher biological value. Oat achieved a higher digestibility, which was also influenced by higher PDCAAS. Buckwheat achieved higher biological protein value. Isoleucine was the limiting amino acid in both tested feeds. Other parameters of the evaluation of protein quality (PER, NPU had minimal differences.

  19. An evaluation of teaching methods in the introductory physics classroom

    Science.gov (United States)

    Savage, Lauren Michelle Williams

    The introductory physics mechanics course at the University of North Carolina at Charlotte has a history of relatively high DFW rates. In 2011, the course was redesigned from the traditional lecture format to the inverted classroom format (flipped). This format inverts the classroom by introducing material in a video assigned as homework while the instructor conducts problem solving activities and guides discussions during the regular meetings. This format focuses on student-centered learning and is more interactive and engaging. To evaluate the effectiveness of the new method, final exam data over the past 10 years was mined and the pass rates examined. A normalization condition was developed to evaluate semesters equally. The two teaching methods were compared using a grade distribution across multiple semesters. Students in the inverted class outperformed those in the traditional class: "A"s increased by 22% and "B"s increased by 38%. The final exam pass rate increased by 12% under the inverted classroom approach. The same analysis was used to compare the written and online final exam formats. Surprisingly, no students scored "A"s on the online final. However, the percent of "B"s increased by 136%. Combining documented best practices from a literature review with personal observations of student performance and attitudes from first hand classroom experience as a teaching assistant in both teaching methods, reasons are given to support the continued use of the inverted classroom approach as well as the online final. Finally, specific recommendations are given to improve the course structure where weaknesses have been identified.

  20. Realistic primary and new productions in a 3D global biogeochemical model: biological complexity or physical forcing?

    Science.gov (United States)

    Popova, E. E.; Coward, A. C.

    2003-04-01

    A nitrogen-based, five compartment biological model has been coupled to a one degree OCCAM (Ocean Circulation and Climate Advanced Modelling Project) model with a KPP ("K profile parameterisation") of the vertical mixing. The biological model state variables are Phytoplankton, Zooplankton, Detritus, Nitrate, and Ammonium. A comparison of the solution with global satellite ocean colour shows that the model is capable of a realistic description of the main seasonal and regional patterns of the surface chlorophyll. Agreement is also good for satellite derived estimates of primary production. In situ data available from local study sites (such as BATS, NABE, India, Papa) are used for the detailed comparison of the model output with the observed ecosystem dynamics in different biological provinces. We discuss performance of the physical and biological model in contrasting areas of the World Ocean. In spite of the biological model being a very simple one, we are able to reproduce the major differences between ecosystem dynamics of these areas. We believe that the success of any global biogeochemical model is dependent first of all on the correct representation of the upper mixed layer (UML) dynamics. Without being able to reproduce contrasting UML regimes in different areas of the World Ocean (such as difference between the North Atlantic and Southern Ocean, or North Atlantic and North Pacific), increased complexity biological models are in danger of producing the right results by the wrong reason.