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Sample records for modeling division asmd

  1. Division Quilts: A Measurement Model

    Science.gov (United States)

    Pratt, Sarah S.; Lupton, Tina M.; Richardson, Kerri

    2015-01-01

    As teachers seek activities to assist students in understanding division as more than just the algorithm, they find many examples of division as fair sharing. However, teachers have few activities to engage students in a quotative (measurement) model of division. Efraim Fischbein and his colleagues (1985) defined two types of whole-number…

  2. Disease manifestations and burden of illness in patients with acid sphingomyelinase deficiency (ASMD).

    Science.gov (United States)

    McGovern, Margaret M; Avetisyan, Ruzan; Sanson, Bernd-Jan; Lidove, Olivier

    2017-02-23

    Acid sphingomyelinase deficiency (ASMD), a rare lysosomal storage disease, is an autosomal recessive genetic disorder caused by different SMPD1 mutations. Historically, ASMD has been classified as Niemann-Pick disease (NPD) types A (NPD A) and B (NPD B). NPD A is associated with a uniformly devastating disease course, with rapidly progressing psychomotor degeneration, leading to death typically by the age of 3 years, most often from respiratory failure. In contrast, the clinical phenotype and life expectancy of patients with NPD B may vary widely. Almost all patients have hepatosplenomegaly and an atherogenic lipid profile, and most patients have interstitial lung disease with progressive impairment of pulmonary function and hematologic abnormalities including cytopenias. Other common clinical manifestations include liver dysfunction, heart disease, skeletal abnormalities and growth delays. Some patients with ASMD who survive beyond early childhood have intermediate phenotypes (variant NPD B) characterized by combinations of non-neurologic and mild to severe neurologic symptoms. The physical and psychosocial burden of illness in patients with NPD B is substantial. Common symptoms include shortness of breath, joint or limb pain, abdominal pain, bleeding and bruising. The disease often leads to chronic fatigue, limited physical or social activity and difficulties in performing daily activities or work. Many patients die before or in early adulthood, often from pneumonia/respiratory failure or liver failure. Available treatments are limited to symptom management and supportive care. An enzyme replacement therapy currently in clinical development is expected to be the first treatment addressing the underlying pathology of the disease. Early diagnosis and appropriate management are essential for reducing the risk of complications. While knowledge about ASMD is evolving, more evidence about ASMD and the natural history across the disease spectrum is needed, to improve

  3. Beyond Cookies: Understanding Various Division Models

    Science.gov (United States)

    Jong, Cindy; Magruder, Robin

    2014-01-01

    Having a deeper understanding of division derived from multiple models is of great importance for teachers and students. For example, students will benefit from a greater understanding of division contexts as they study long division, fractions, and division of fractions. The purpose of this article is to build on teachers' and students'…

  4. Cell Division in the Light of Modeling.

    Science.gov (United States)

    Bellaïche, Yohanns

    2016-09-26

    Theoretical modeling is central to elucidating underlying principles of emergent properties of complex systems. In cell and developmental biology, the last 15 years have witnessed a convergence of empirical and modeling approaches for fresh perspectives. The role of cell division in coordinating size, shape, and fate in particular illustrates the ever-growing impact of modeling.

  5. An electrostatic model for biological cell division

    CERN Document Server

    Faraggi, Eshel

    2010-01-01

    Probably the most fundamental processes for biological systems is their ability to create themselves through the use of cell division and cell differentiation. In this work a simple physical model is proposed for biological cell division. The model consists of a positive ionic gradient across the cell membrane, and concentration of charge at the nodes of the spindle and on the chromosomes. A simple calculation, based on Coulomb's Law, shows that under such circumstances a chromosome will tend to break up to its constituent chromatids and that the chromatids will be separated by a distance that is an order of thirty percent of the distance between the spindle nodes. Further repulsion between the nodes will tend to stretch the cell and eventually break the cell membrane between the separated chromatids, leading to cell division. The importance of this work is in continuing the understanding of the electromagnetic basis of cell division and providing it with an analytical model. A central implication of this and...

  6. The ‘division of labour’ model of eye evolution

    National Research Council Canada - National Science Library

    Detlev Arendt; Harald Hausen; Günter Purschke

    2009-01-01

    The ‘division of labour’ model of eye evolution is elaborated here. We propose that the evolution of complex, multicellular animal eyes started from a single, multi-functional cell type that existed in metazoan ancestors...

  7. Composite Linear Models | Division of Cancer Prevention

    Science.gov (United States)

    By Stuart G. Baker The composite linear models software is a matrix approach to compute maximum likelihood estimates and asymptotic standard errors for models for incomplete multinomial data. It implements the method described in Baker SG. Composite linear models for incomplete multinomial data. Statistics in Medicine 1994;13:609-622. The software includes a library of thirty examples from the literature. |

  8. Relevant parameters in models of cell division control

    CERN Document Server

    Grilli, Jacopo; Kennard, Andrew S; Lagomarsino, Marco Cosentino

    2016-01-01

    A recent burst of dynamic single-cell growth-division data makes it possible to characterize the stochastic dynamics of cell division control in bacteria. Different modeling frameworks were used to infer specific mechanisms from such data, but the links between frameworks are poorly explored, with relevant consequences for how well any particular mechanism can be supported by the data. Here, we describe a simple and generic framework in which two common formalisms can be used interchangeably: (i) a continuous-time division process described by a hazard function and (ii) a discrete-time equation describing cell size across generations (where the unit of time is a cell cycle). In our framework, this second process is a discrete-time Langevin equation with a simple physical analogue. By perturbative expansion around the mean initial size (or inter-division time), we show explicitly how this framework describes a wide range of division control mechanisms, including combinations of time and size control, as well a...

  9. Equilibrium Price Dispersion in a Matching Model with Divisible Money

    NARCIS (Netherlands)

    Kamiya, K.; Sato, T.

    2002-01-01

    The main purpose of this paper is to show that, for any given parameter values, an equilibrium with dispersed prices (two-price equilibrium) exists in a simple matching model with divisible money presented by Green and Zhou (1998).We also show that our two-price equilibrium is unique in certain envi

  10. Fraction Multiplication and Division Models: A Practitioner Reference Paper

    Science.gov (United States)

    Ervin, Heather K.

    2017-01-01

    It is well documented in literature that rational number is an important area of understanding in mathematics. Therefore, it follows that teachers and students need to have an understanding of rational number and related concepts such as fraction multiplication and division. This practitioner reference paper examines models that are important to…

  11. Relevant parameters in models of cell division control

    Science.gov (United States)

    Grilli, Jacopo; Osella, Matteo; Kennard, Andrew S.; Lagomarsino, Marco Cosentino

    2017-03-01

    A recent burst of dynamic single-cell data makes it possible to characterize the stochastic dynamics of cell division control in bacteria. Different models were used to propose specific mechanisms, but the links between them are poorly explored. The lack of comparative studies makes it difficult to appreciate how well any particular mechanism is supported by the data. Here, we describe a simple and generic framework in which two common formalisms can be used interchangeably: (i) a continuous-time division process described by a hazard function and (ii) a discrete-time equation describing cell size across generations (where the unit of time is a cell cycle). In our framework, this second process is a discrete-time Langevin equation with simple physical analogues. By perturbative expansion around the mean initial size (or interdivision time), we show how this framework describes a wide range of division control mechanisms, including combinations of time and size control, as well as the constant added size mechanism recently found to capture several aspects of the cell division behavior of different bacteria. As we show by analytical estimates and numerical simulations, the available data are described precisely by the first-order approximation of this expansion, i.e., by a "linear response" regime for the correction of size fluctuations. Hence, a single dimensionless parameter defines the strength and action of the division control against cell-to-cell variability (quantified by a single "noise" parameter). However, the same strength of linear response may emerge from several mechanisms, which are distinguished only by higher-order terms in the perturbative expansion. Our analytical estimate of the sample size needed to distinguish between second-order effects shows that this value is close to but larger than the values of the current datasets. These results provide a unified framework for future studies and clarify the relevant parameters at play in the control of

  12. Growth and Division of Active Droplets: A Model for Protocells

    CERN Document Server

    Zwicker, David; Weber, Christoph A; Hyman, Anthony A; Jülicher, Frank

    2016-01-01

    It has been proposed that during the early steps in the origin of life, small droplets could have formed via the segregation of molecules from complex mixtures by phase separation. These droplets could have provided chemical reaction centers. However, whether these droplets could divide and propagate is unclear. Here we examine the behavior of droplets in systems that are maintained away from thermodynamic equilibrium by an external supply of energy. In these systems, droplets grow by the addition of droplet material generated by chemical reactions. Surprisingly, we find that chemically driven droplet growth can lead to shape instabilities that trigger the division of droplets into two smaller daughters. Therefore, chemically active droplets can exhibit cycles of growth and division that resemble the proliferation of living cells. Dividing active droplets could serve as a model for prebiotic protocells, where chemical reactions in the droplet play the role of a prebiotic metabolism.

  13. Replicating vesicles as models of primitive cell growth and division.

    Science.gov (United States)

    Hanczyc, Martin M; Szostak, Jack W

    2004-12-01

    Primitive cells, lacking the complex bio-machinery present in modern cells, would have had to rely on the self-organizing properties of their components and on interactions with their environment to achieve basic cellular functions such as growth and division. Many bilayer-membrane vesicles, depending on their composition and environment, can exhibit complex morphological changes such as growth, fusion, fission, budding, internal vesicle assembly and vesicle-surface interactions. The rich dynamic properties of these vesicles provide interesting models of how primitive cellular replication might have occurred in response to purely physical and chemical forces.

  14. Modelling hierarchical and modular complex networks: division and independence

    Science.gov (United States)

    Kim, D.-H.; Rodgers, G. J.; Kahng, B.; Kim, D.

    2005-06-01

    We introduce a growing network model which generates both modular and hierarchical structure in a self-organized way. To this end, we modify the Barabási-Albert model into the one evolving under the principles of division and independence as well as growth and preferential attachment (PA). A newly added vertex chooses one of the modules composed of existing vertices, and attaches edges to vertices belonging to that module following the PA rule. When the module size reaches a proper size, the module is divided into two, and a new module is created. The karate club network studied by Zachary is a simple version of the current model. We find that the model can reproduce both modular and hierarchical properties, characterized by the hierarchical clustering function of a vertex with degree k, C(k), being in good agreement with empirical measurements for real-world networks.

  15. Random matrix models of stochastic integral type for free infinitely divisible distributions

    CERN Document Server

    Molina, J Armando Domínguez

    2010-01-01

    The Bercovici-Pata bijection maps the set of classical infinitely divisible distributions to the set of free infinitely divisible distributions. The purpose of this work is to study random matrix models for free infinitely divisible distributions under this bijection. First, we find a specific form of the polar decomposition for the L\\'{e}vy measures of the random matrix models considered in Benaych-Georges who introduced the models through their measures. Second, random matrix models for free infinitely divisible distributions are built consisting of infinitely divisible matrix stochastic integrals whenever their corresponding classical infinitely divisible distributions admit stochastic integral representations. These random matrix models are realizations of random matrices given by stochastic integrals with respect to matrix-valued L\\'{e}vy processes. Examples of these random matrix models for several classes of free infinitely divisible distributions are given. In particular, it is shown that any free sel...

  16. Probabilistic model of microbial cell growth, division, and mortality.

    Science.gov (United States)

    Horowitz, Joseph; Normand, Mark D; Corradini, Maria G; Peleg, Micha

    2010-01-01

    After a short time interval of length deltat during microbial growth, an individual cell can be found to be divided with probability Pd(t)deltat, dead with probability Pm(t)deltat, or alive but undivided with the probability 1-[Pd(t)+Pm(t)]deltat, where t is time, Pd(t) expresses the probability of division for an individual cell per unit of time, and Pm(t) expresses the probability of mortality per unit of time. These probabilities may change with the state of the population and the habitat's properties and are therefore functions of time. This scenario translates into a model that is presented in stochastic and deterministic versions. The first, a stochastic process model, monitors the fates of individual cells and determines cell numbers. It is particularly suitable for small populations such as those that may exist in the case of casual contamination of a food by a pathogen. The second, which can be regarded as a large-population limit of the stochastic model, is a continuous mathematical expression that describes the population's size as a function of time. It is suitable for large microbial populations such as those present in unprocessed foods. Exponential or logistic growth with or without lag, inactivation with or without a "shoulder," and transitions between growth and inactivation are all manifestations of the underlying probability structure of the model. With temperature-dependent parameters, the model can be used to simulate nonisothermal growth and inactivation patterns. The same concept applies to other factors that promote or inhibit microorganisms, such as pH and the presence of antimicrobials, etc. With Pd(t) and Pm(t) in the form of logistic functions, the model can simulate all commonly observed growth/mortality patterns. Estimates of the changing probability parameters can be obtained with both the stochastic and deterministic versions of the model, as demonstrated with simulated data.

  17. The Role of Implicit Models in Solving Verbal Problems in Multiplication and Division.

    Science.gov (United States)

    Fischbein, Efraim; And Others

    1985-01-01

    Over 600 pupils in grades five, seven, and nine in Italian schools were asked to choose the operation needed to solve 26 multiplication and division word problems. The findings seemed to confirm the impact of the repeated addition model on multiplication and of the partitive model on division. (MNS)

  18. Molecular Code Division Multiple Access: Gaussian Mixture Modeling

    Science.gov (United States)

    Zamiri-Jafarian, Yeganeh

    Communications between nano-devices is an emerging research field in nanotechnology. Molecular Communication (MC), which is a bio-inspired paradigm, is a promising technique for communication in nano-network. In MC, molecules are administered to exchange information among nano-devices. Due to the nature of molecular signals, traditional communication methods can't be directly applied to the MC framework. The objective of this thesis is to present novel diffusion-based MC methods when multi nano-devices communicate with each other in the same environment. A new channel model and detection technique, along with a molecular-based access method, are proposed in here for communication between asynchronous users. In this work, the received molecular signal is modeled as a Gaussian mixture distribution when the MC system undergoes Brownian noise and inter-symbol interference (ISI). This novel approach demonstrates a suitable modeling for diffusion-based MC system. Using the proposed Gaussian mixture model, a simple receiver is designed by minimizing the error probability. To determine an optimum detection threshold, an iterative algorithm is derived which minimizes a linear approximation of the error probability function. Also, a memory-based receiver is proposed to improve the performance of the MC system by considering previously detected symbols in obtaining the threshold value. Numerical evaluations reveal that theoretical analysis of the bit error rate (BER) performance based on the Gaussian mixture model match simulation results very closely. Furthermore, in this thesis, molecular code division multiple access (MCDMA) is proposed to overcome the inter-user interference (IUI) caused by asynchronous users communicating in a shared propagation environment. Based on the selected molecular codes, a chip detection scheme with an adaptable threshold value is developed for the MCDMA system when the proposed Gaussian mixture model is considered. Results indicate that the

  19. Stochastic modeling of cell growth with symmetric or asymmetric division

    Science.gov (United States)

    Marantan, Andrew; Amir, Ariel

    2016-07-01

    We consider a class of biologically motivated stochastic processes in which a unicellular organism divides its resources (volume or damaged proteins, in particular) symmetrically or asymmetrically between its progeny. Assuming the final amount of the resource is controlled by a growth policy and subject to additive and multiplicative noise, we derive the recursive integral equation describing the evolution of the resource distribution over subsequent generations and use it to study the properties of stable resource distributions. We find conditions under which a unique stable resource distribution exists and calculate its moments for the class of affine linear growth policies. Moreover, we apply an asymptotic analysis to elucidate the conditions under which the stable distribution (when it exists) has a power-law tail. Finally, we use the results of this asymptotic analysis along with the moment equations to draw a stability phase diagram for the system that reveals the counterintuitive result that asymmetry serves to increase stability while at the same time widening the stable distribution. We also briefly discuss how cells can divide damaged proteins asymmetrically between their progeny as a form of damage control. In the appendixes, motivated by the asymmetric division of cell volume in Saccharomyces cerevisiae, we extend our results to the case wherein mother and daughter cells follow different growth policies.

  20. Xenopus as a model for studies in mechanical stress and cell division.

    Science.gov (United States)

    Stooke-Vaughan, Georgina A; Davidson, Lance A; Woolner, Sarah

    2017-01-01

    We exist in a physical world, and cells within biological tissues must respond appropriately to both environmental forces and forces generated within the tissue to ensure normal development and homeostasis. Cell division is required for normal tissue growth and maintenance, but both the direction and rate of cell division must be tightly controlled to avoid diseases of over-proliferation such as cancer. Recent studies have shown that mechanical cues can cause mitotic entry and orient the mitotic spindle, suggesting that physical force could play a role in patterning tissue growth. However, to fully understand how mechanics guides cells in vivo, it is necessary to assess the interaction of mechanical strain and cell division in a whole tissue context. In this mini-review we first summarise the body of work linking mechanics and cell division, before looking at the advantages that the Xenopus embryo can offer as a model organism for understanding: (1) the mechanical environment during embryogenesis, and (2) factors important for cell division. Finally, we introduce a novel method for applying a reproducible strain to Xenopus embryonic tissue and assessing subsequent cell divisions. © 2017 Wiley Periodicals, Inc.

  1. A dynamic model of tomato fruit growth integrating cell division, cell growth and endoreduplication

    NARCIS (Netherlands)

    Fanwoua, J.; Visser, de P.H.B.; Heuvelink, E.; Yin, X.; Struik, P.C.; Marcelis, L.F.M.

    2013-01-01

    In this study, we developed a model of tomato (Solanum lycopersicum L.) fruit growth integrating cell division, cell growth and endoreduplication. The fruit was considered as a population of cells grouped in cell classes differing in their initial cell age and cell mass. The model describes fruit gr

  2. Cognitive Models: The Missing Link to Learning Fraction Multiplication and Division

    Science.gov (United States)

    de Castro, Belinda V.

    2008-01-01

    This quasi-experimental study aims to streamline cognitive models on fraction multiplication and division that contain the most worthwhile features of other existing models. Its exploratory nature and its approach to proof elicitation can be used to help establish its effectiveness in building students' understanding of fractions as compared to…

  3. Divisive latent class modeling as a density estimation method for categorical data

    NARCIS (Netherlands)

    van der Palm, D.W.; van der Ark, L.A.; Vermunt, J.K.

    2016-01-01

    Traditionally latent class (LC) analysis is used by applied researchers as a tool for identifying substantively meaningful clusters. More recently, LC models have also been used as a density estimation tool for categorical variables. We introduce a divisive LC (DLC) model as a density estimation too

  4. Long division unites - long union divides, a model for social network evolution

    CERN Document Server

    Jian, Jiang; Michel, Pezeril; Qiuping-Alexandre, Wang

    2013-01-01

    A remarkable phenomenon in the time evolution of many networks such as cultural, political, national and economic systems, is the recurrent transition between the states of union and division of nodes. In this work, we propose a phenomenological modeling, inspired by the maxim "long union divides and long division unites", in order to investigate the evolutionary characters of these networks composed of the entities whose behaviors are dominated by these two events. The nodes are endowed with quantities such as identity, ingredient, richness (power), openness (connections), age, distance, interaction etc. which determine collectively the evolution in a probabilistic way. Depending on a tunable parameter, the time evolution of this model is mainly an alternative domination of union or division state, with a possible state of final union dominated by one single node.

  5. Computational Model of the Division Cycle of Caulobacter crescentus

    Science.gov (United States)

    Brazhnik, Paul; Li, Shenghua; Sobral, Bruno; Tyson, John J.

    2007-11-01

    Based on published experimental evidence, we propose a molecular mechanism and a quantitative computational model for cell cycle control in Caulobacter crescentus. Our model predicts the detailed temporal dynamics of regulatory gene expression during the cell cycle and differentiation process of wild-type cells as well as several mutant strains. Since many of the proteins involved in regulating the cell cycle of C.crescentus are conserved among other genera of α-proteobacteria, the proposed mechanism may be applicable to these species.

  6. Universal Protein Distributions in a Model of Cell Growth and Division

    CERN Document Server

    Brenner, Naama; Osmanovic, Dino; Rabin, Yitzhak; Salman, Hanna; Stein, D L

    2015-01-01

    Protein distributions measured under a broad set of conditions in bacteria and yeast exhibit a universal skewed shape, with variances depending quadratically on means. For bacteria these properties are reproduced by protein accumulation and division dynamics across generations. We present a stochastic growth-and-division model with feedback which captures these observed properties. The limiting copy number distribution is calculated exactly, and a single parameter is found to determine the distribution shape and the variance-to-mean relation. Estimating this parameter from bacterial temporal data reproduces the measured universal distribution shape with high accuracy, and leads to predictions for future experiments.

  7. Tomato fruit growth : integrating cell division, cell growth and endoreduplication by experimentation and modelling

    NARCIS (Netherlands)

    Fanwoua, J.

    2012-01-01

    Keywords: cell division, cell growth, cell endoreduplication, fruit growth, genotype, G×E interaction, model, tomato. Fruit size is a major component of fruit yield and quality of many crops. Variations in fruit size can be tremendous due to genotypic and environmental factors. The mechanisms

  8. Growth and Division in a Dynamic Protocell Model

    Directory of Open Access Journals (Sweden)

    Marco Villani

    2014-12-01

    Full Text Available In this paper a new model of growing and dividing protocells is described, whose main features are (i a lipid container that grows according to the composition of the molecular milieu (ii a set of “genetic memory molecules” (GMMs that undergo catalytic reactions in the internal aqueous phase and (iii a set of stochastic kinetic equations for the GMMs. The mass exchange between the external environment and the internal phase is described by simulating a semipermeable membrane and a flow driven by the differences in chemical potentials, thereby avoiding to resort to sometimes misleading simplifications, e.g., that of a flow reactor. Under simple assumptions, it is shown that synchronization takes place between the rate of replication of the GMMs and that of the container, provided that the set of reactions hosts a so-called RAF (Reflexive Autocatalytic, Food-generated set whose influence on synchronization is hereafter discussed. It is also shown that a slight modification of the basic model that takes into account a rate-limiting term, makes possible the growth of novelties, allowing in such a way suitable evolution: so the model represents an effective basis for understanding the main abstract properties of populations of protocells.

  9. The Time Division Multi-Channel Communication Model and the Correlative Protocol Based on Quantum Time Division Multi-Channel Communication

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-Hui; PEI Chang-Xing; NIE Min

    2010-01-01

    @@ Based on the classical time division multi-channel communication theory,we present a scheme of quantum time-division multi-channel communication(QTDMC).Moreover,the model of quantum time division switch(QTDS)and correlative protocol of QTDMC are proposed.The quantum bit error rate(QBER)is analyzed and the QBER simulation test is performed.The scheme shows that the QTDS can carry out multi-user communication through quantum channel,the QBER can also reach the reliability requirement of communication,and the protocol of QTDMC has high practicability and transplantable.The scheme of QTDS may play an important role in the establishment of quantum communication in a large scale in the future.

  10. Modeling Human Serum Albumin Tertiary Structure to Teach Upper-Division Chemistry Students Bioinformatics and Homology Modeling Basics

    Science.gov (United States)

    Petrovic, Dus?an; Zlatovic´, Mario

    2015-01-01

    A homology modeling laboratory experiment has been developed for an introductory molecular modeling course for upper-division undergraduate chemistry students. With this experiment, students gain practical experience in homology model preparation and assessment as well as in protein visualization using the educational version of PyMOL…

  11. Modeling Human Serum Albumin Tertiary Structure to Teach Upper-Division Chemistry Students Bioinformatics and Homology Modeling Basics

    Science.gov (United States)

    Petrovic, Dus?an; Zlatovic´, Mario

    2015-01-01

    A homology modeling laboratory experiment has been developed for an introductory molecular modeling course for upper-division undergraduate chemistry students. With this experiment, students gain practical experience in homology model preparation and assessment as well as in protein visualization using the educational version of PyMOL…

  12. The Battlefield Environment Division Modeling Framework (BMF). Part 2. Serial and Parallel Output Enhancements

    Science.gov (United States)

    2014-11-01

    Army position unless so designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an official...high- performance computing (HPC) and overall data longevity . The Battlefield Environment Division Modeling Framework (BMF) v0.90 was developed for the...use of object-oriented program (OOP) design . Here we extend BMF to include IO functionality for serial and distributed compute configurations. The

  13. A model for the Escherichia coli FtsB/FtsL/FtsQ cell division complex

    Directory of Open Access Journals (Sweden)

    Lagos Rosalba

    2011-06-01

    Full Text Available Abstract Background Bacterial division is produced by the formation of a macromolecular complex in the middle of the cell, called the divisome, formed by more than 10 proteins. This process can be divided into two steps, in which the first is the polymerization of FtsZ to form the Z ring in the cytoplasm, and then the sequential addition of FtsA/ZipA to anchor the ring at the cytoplasmic membrane, a stage completed by FtsEX and FtsK. In the second step, the formation of the peptidoglycan synthesis machinery in the periplasm takes place, followed by cell division. The proteins involved in connecting both steps in cell division are FtsQ, FtsB and FtsL, and their interaction is a crucial and conserved event in the division of different bacteria. These components are small bitopic membrane proteins, and their specific function seems to be mainly structural. The purpose of this study was to obtain a structural model of the periplasmic part of the FtsB/FtsL/FtsQ complex, using bioinformatics tools and experimental data reported in the literature. Results Two oligomeric models for the periplasmic region of the FtsB/FtsL/FtsQ E. coli complex were obtained from bioinformatics analysis. The FtsB/FtsL subcomplex was modelled as a coiled-coil based on sequence information and several stoichiometric possibilities. The crystallographic structure of FtsQ was added to this complex, through protein-protein docking. Two final structurally-stable models, one trimeric and one hexameric, were obtained. The nature of the protein-protein contacts was energetically favourable in both models and the overall structures were in agreement with the experimental evidence reported. Conclusions The two models obtained for the FtsB/FtsL/FtsQ complex were stable and thus compatible with the in vivo periplasmic complex structure. Although the hexameric model 2:2:2 has features that indicate that this is the most plausible structure, the ternary complex 1:1:1 cannot be discarded

  14. A polymerization–depolymerization model for generation of contractile force during bacterial cell division

    Indian Academy of Sciences (India)

    Biplab Ghosh; Anirban Sain

    2008-08-01

    During the last phase of cell division in bacteria, a polymeric ring forms at the division site. The ring, made of intracellular proteins, anchors to the cell wall and starts to contract. That initiates a dividing septum to close in, like the shutter of a camera, eventually guillotining the cell into two daughters. All through, the ring remains at the leading edge of the septum and seems to power its closure. It is not understood why does the ring contract. We propose a theoretical model to explain this. It is worth mentioning that a similar contraction phenomenon occurs for the actin ring in eukaryotes, but there it is due to motor proteins, which however, are absent in bacteria.

  15. Growth and division of active droplets provides a model for protocells

    Science.gov (United States)

    Zwicker, David; Seyboldt, Rabea; Weber, Christoph A.; Hyman, Anthony A.; Jülicher, Frank

    2017-04-01

    It has been proposed that during the early steps in the origin of life, small droplets could have formed via the segregation of molecules from complex mixtures by phase separation. These droplets could have provided chemical reaction centres. However, whether these droplets could divide and propagate is unclear. Here we examine the behaviour of droplets in systems that are maintained away from thermodynamic equilibrium by an external supply of energy. In these systems, droplets grow by the addition of droplet material generated by chemical reactions. Surprisingly, we find that chemically driven droplet growth can lead to shape instabilities that trigger the division of droplets into two smaller daughters. Therefore, chemically active droplets can exhibit cycles of growth and division that resemble the proliferation of living cells. Dividing active droplets could serve as a model for prebiotic protocells, where chemical reactions in the droplet play the role of a prebiotic metabolism.

  16. American College Football Division I Team Attachment: A Model for Sponsorship Effectiveness

    Directory of Open Access Journals (Sweden)

    Hsin-Chung Chen

    2013-10-01

    Full Text Available The purpose of this study was to examine sponsorship effectiveness at the Division I level, including the relationship between fans and sponsors. To collect the necessary data, the 13-item questionnaire was disseminated at two college football games by volunteer sampling at three Division I universities in the United States. With a total of 407 respondents, LISREL 8.52 and SPSS 17.0 were used to analyze the data for descriptive statistics, CFA, and SEM. By utilizing SEM, the variables of team attachment, sponsor image, word of mouth, and purchase intentions fit the proposed model.  Pragmatically, the significance of team attachment can be understated in its role as an initial construct to begin the sponsorship process. Considering the construct of sponsor image as a mediating variable, sponsor image played an important role to anticipate an increase in positive word of mouth or an increase in consumer purchase intentions.

  17. Model-Based Reasoning in the Upper-Division Physics Laboratory: Framework and Initial Results

    CERN Document Server

    Zwickl, Benjamin M; Finkelstein, Noah; Lewandowski, H J

    2014-01-01

    Constructing and using models are core scientific practices that have gained significant attention within K-12 and higher education. Although modeling is a broadly applicable process, within physics education, it has been preferentially applied to the iterative development of broadly applicable principles (e.g., Newton's laws of motion in introductory mechanics). We review and extend existing frameworks on modeling to develop a new framework that more naturally describes model-based reasoning in upper-division physics labs. A significant feature of the new framework is that measurement tools (in addition to the physical system being studied) are subjected to the process of modeling. Think-aloud interviews were used to document examples of model-based reasoning in the laboratory and refine the modeling framework. The interviews showed how students productively applied similar facets of modeling to the physical system and measurement tools: construction, prediction, interpretation of data, identification of mod...

  18. Mechanism of murine epidermal maintenance: Cell division and the Voter Model

    CERN Document Server

    Klein, Allon M; Jones, Philip H; Simons, Benjamin D

    2007-01-01

    This paper presents an interesting experimental example of voter-model statistics in biology. In recent work on mouse tail-skin, where proliferating cells are confined to a two-dimensional layer, we showed that cells proliferate and differentiate according to a simple stochastic model of cell division involving just one type of proliferating cell that may divide both symmetrically and asymmetrically. Curiously, these simple rules provide excellent predictions of the cell population dynamics without having to address their spatial distribution. Yet, if the spatial behaviour of cells is addressed by allowing cells to diffuse at random, one deduces that density fluctuations destroy tissue confluence, implying some hidden degree of spatial regulation in the physical system. To infer the mechanism of spatial regulation, we consider a two-dimensional model of cell fate that preserves the overall population dynamics. By identifying the resulting behaviour with a three-species variation of the "Voter" model, we predi...

  19. Baseline requirements of the proposed action for the Transportation Management Division routing models

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, P.E.; Joy, D.S.

    1995-02-01

    The potential impacts associated with the transportation of hazardous materials are important to shippers, carriers, and the general public. This is particularly true for shipments of radioactive material. The shippers are primarily concerned with safety, security, efficiency, and equipment requirements. The carriers are concerned with the potential impact that radioactive shipments may have on their operations--particularly if such materials are involved in an accident. The general public has also expressed concerns regarding the safety of transporting radioactive and other hazardous materials through their communities. Because transportation routes are a central concern in hazardous material transport, the prediction of likely routes is the first step toward resolution of these issues. In response to these routing needs, several models have been developed over the past fifteen years at Oak Ridge National Laboratory (ORNL). The HIGHWAY routing model is used to predict routes for truck transportation, the INTERLINE routing model is used to predict both rail and barge routes, and the AIRPORT locator model is used to determine airports with specified criteria near a specific location. As part of the ongoing improvement of the US Department of Energy`s (DOE) Environmental Management Transportation Management Division`s (EM-261) computer systems and development efforts, a Baseline Requirements Assessment Session on the HIGHWAY, INTERLINE, and AIRPORT models was held at ORNL on April 27, 1994. The purpose of this meeting was to discuss the existing capabilities of the models and data bases and to review enhancements of the models and data bases to expand their usefulness. The results of the Baseline Requirements Assessment Section will be discussed in this report. The discussions pertaining to the different models are contained in separate sections.

  20. Meta-Boolean models of asymmetric division patterns in the C. elegans intestinal lineage

    Science.gov (United States)

    Pettersson, Sofia; Forchheimer, Robert; Larsson, Jan-Åke

    2013-01-01

    The intestine of Caenorhabditis elegans is derived from 20 cells that are organized into nine intestinal rings. During embryogenesis, three of the rings rotate approximately 90 degrees in a process known as intestinal twist. The underlying mechanisms for this morphological event are not fully known, but it has been demonstrated that both left-right and anterior-posterior asymmetry is required for intestinal twist to occur. We have recently presented a rule-based meta-Boolean tree model intended to describe complex lineages. In this report we apply this model to the E lineage of C. elegans, specifically targeting the asymmetric anterior-posterior division patterns within the lineage. The resulting model indicates that cells with the same factor concentration are located next to each other in the intestine regardless of lineage origin. In addition, the shift in factor concentrations coincides with the boundary for intestinal twist. When modeling lit-1 mutant data according to the same principle, the factor distributions in each cell are altered, yet the concurrence between the shift in concentration and intestinal twist remains. This pattern suggests that intestinal twist is controlled by a threshold mechanism. In the current paper we present the factor concentrations for all possible combinations of symmetric and asymmetric divisions in the E lineage and relate these to the potential threshold by studying existing data for wild-type and mutant embryos. Finally, we discuss how the resulting models can serve as a basis for experimental design in order to reveal the underlying mechanisms of intestinal twist. PMID:24058861

  1. Evolution of heritable behavioural differences in a model of social division of labour

    Directory of Open Access Journals (Sweden)

    Zsóka Vásárhelyi

    2015-05-01

    Full Text Available The spectacular diversity of personality and behaviour of animals and humans has evoked many hypotheses intended to explain its developmental and evolutionary background. Although the list of the possible contributing mechanisms seems long, we propose that an underemphasised explanation is the division of labour creating negative frequency dependent selection. We use analytical and numerical models of social division of labour to show how selection can create consistent and heritable behavioural differences in a population, where randomly sampled individuals solve a collective task together. We assume that the collective task needs collaboration of individuals performing one of the two possible subtasks. The total benefit of the group is highest when the ratio of different subtasks is closest to 1. The probability of choosing one of the two costly subtasks and the costs assigned to them are under selection. By using adaptive dynamics we show that if a trade-off between the costs of the subtasks is strong enough, then evolution leads to coexistence of specialized individuals performing one of the subtasks with high probability and low cost. Our analytical results were verified and extended by numerical simulations.

  2. A Model for Integrating Computation in Undergraduate Physics: An example from middle-division classical mechanics

    CERN Document Server

    Caballero, Marcos D

    2013-01-01

    Much of the research done by modern physicists would be impossible without the use of computation. And yet, while computation is a crucial tool of practicing physicists, physics curricula do not generally reflect its importance and utility. To more tightly connect undergraduate preparation with professional practice, we integrated computational instruction into middle-division classical mechanics at the University of Colorado Boulder. Our model for integration includes the construction of computational learning goals, the design of computational activities consistent with those goals, and the assessment of students' computational fluency. To assess students' computational fluency, we used open-ended computational projects in which students prepared reports describing a physical problem of their choosing. Many students chose projects from outside the domain of the course, and therefore, had to employ mathematical and computational techniques they had not yet been taught. After completing the project, most stud...

  3. Electrospun cerium nitrate/polymer composite fibres:synthesis, characterization and fibre-division model

    Institute of Scientific and Technical Information of China (English)

    Li Meng-Meng; Long Yun-Ze; Yin Hong-Xing; Zhang Zhi-Ming

    2011-01-01

    Cerium (III)nitrate/poly(vinylpyrrolidone)(Ce(NO3)3/PVP)composite fibres have been prepared by electrospinning. After calcining the composite fibres in air at 500℃, CeO2 nanowires were obtained. The characterizations of the as-spun composite fibres and resultant nanowires have been carried out by a scanning electron microscope (SEM),an infrared spectrometer, an x-ray diffractometer and a fluorescence spectrophotometer. Interestingly, some unusual ribbon-like or twin fibres were observed besides the common fibres with circular or elliptic cross sections. We developed a fibre-division model resulting from Coulomb repulsion and solvent vaporization to interpret the formation of the ribbona or twin fibres, which has been confirmed by the SEM studies. Our results also indicate that the formation of the ribbons or twin fibres is less dependent on operation voltage and work distance.

  4. Development of Biological Movement Recognition by Interaction between Active Basis Model and Fuzzy Optical Flow Division

    Directory of Open Access Journals (Sweden)

    Bardia Yousefi

    2014-01-01

    Full Text Available Following the study on computational neuroscience through functional magnetic resonance imaging claimed that human action recognition in the brain of mammalian pursues two separated streams, that is, dorsal and ventral streams. It follows up by two pathways in the bioinspired model, which are specialized for motion and form information analysis (Giese and Poggio 2003. Active basis model is used to form information which is different from orientations and scales of Gabor wavelets to form a dictionary regarding object recognition (human. Also biologically movement optic-flow patterns utilized. As motion information guides share sketch algorithm in form pathway for adjustment plus it helps to prevent wrong recognition. A synergetic neural network is utilized to generate prototype templates, representing general characteristic form of every class. Having predefined templates, classifying performs based on multitemplate matching. As every human action has one action prototype, there are some overlapping and consistency among these templates. Using fuzzy optical flow division scoring can prevent motivation for misrecognition. We successfully apply proposed model on the human action video obtained from KTH human action database. Proposed approach follows the interaction between dorsal and ventral processing streams in the original model of the biological movement recognition. The attained results indicate promising outcome and improvement in robustness using proposed approach.

  5. Well-posedness and asynchronous exponential growth of solutions of a two-phase cell division model

    Directory of Open Access Journals (Sweden)

    Meng Bai

    2010-04-01

    Full Text Available In this article we study a two-phase cell division model. The cells of the two different phases have different growth rates. We mainly consider the model of equal mitosis. By using the semigroup theory, we prove that this model is well-posed in suitable function spaces and its solutions have the property of asynchronous exponential growth as time approaches infinity. The corresponding model of asymmetric mitosis is also studied and similar results are obtained.

  6. Computational Fair Division

    DEFF Research Database (Denmark)

    Branzei, Simina

    Fair division is a fundamental problem in economic theory and one of the oldest questions faced through the history of human society. The high level scenario is that of several participants having to divide a collection of resources such that everyone is satisfied with their allocation -- e.g. two...... heirs dividing a car, house, and piece of land inherited. The literature on fair division was developed in the 20th century in mathematics and economics, but computational work on fair division is still sparse. This thesis can be seen as an excursion in computational fair division divided in two parts...... study alternative and richer models, such as externalities in cake cutting, simultaneous cake cutting, and envy-free cake cutting. The second part of the thesis tackles the fair allocation of multiple goods, divisible and indivisible. In the realm of divisible goods, we investigate the well known...

  7. Flow cytometric quantification of T cell proliferation and division kinetics in woodchuck model of hepatitis B.

    Science.gov (United States)

    Gujar, Shashi A; Michalak, Tomasz I

    2005-01-01

    Woodchucks infected with woodchuck hepatitis virus (WHV) represent the closest natural animal model to study the immunopathogenesis of liver injury caused by essentially noncytopathic, highly human specific hepatitis B virus (HBV). The importance of antiviral T cell response in induction of hepatitis and in control of HBV replication has been demonstrated. However, the understanding of how these responses contribute to the development of different immunomorphological forms of liver disease and their outcomes remain elusive. In this study, we established and standardized a flow cytometry assay using peripheral blood mononuclear cells labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE) to assess WHV-specific and mitogen-driven T lymphocyte proliferative responses in woodchucks. The assay is of significantly greater sensitivity than the adenine incorporation assay currently used when applied to measure either WHV-specific T cell responses in acute (P measuring cell division rates. The study shows that woodchuck PBMC labeled with CFSE exhibit light scatter and fluorescence profiles compatible to those of human PBMC, allowing quantitation and deconvolution of the flow cytometric data by applying the existing analytical softwares. The availability of this novel assay should facilitate a more precise and comprehensive evaluation of hepadnavirus-specific and generalized T cell responses in experimental WHV hepatitis.

  8. Cell cycle kinetics with supramitotic control, two cell types, and unequal division: a model of transformed embryonic cells.

    Science.gov (United States)

    Kimmel, M; Arino, O

    1991-06-01

    We develop a mathematical model of cell cycle kinetics of transformed embryonic cells. The model includes supramitotic regulation, in which decisions regarding growth control are made at a point inside the cell division cycle and their impact extends to the next decision point, located in the next division cycle. Another feature is the presence of two varieties of cells, which switch from one to the other with given transition probabilities. The third factor considered is unequal division of cells, also defined in probabilistic terms. We provide a rigorous description of the model and derivation of its equations and analyze its asymptotic properties by defining and investigating an abstract semigroup of positive linear operators in appropriate state space. The spectral properties of the semigroup yield the balanced exponential growth law for the model. To compare the model to experimental data, we derive basic pedigree statistics, beta curves, and generation time correlations. We present numerical calculations based on measurements available for the embryonic cells. We conclude that to yield the experimentally obtained pedigree statistics, switches from one cell variety to the other must be quite infrequent.

  9. Brood temperature, task division and colony survival in honeybees : A model

    NARCIS (Netherlands)

    Becher, Matthias A.; Hildenbrandt, Hanno; Hemelrijk, Charlotte K.; Moritz, Robin F. A.

    2010-01-01

    One of the mechanisms by which honeybees regulate division of labour among their colony members is age polyethism. Here the younger bees perform in-hive tasks such as heating and the older ones carry out tasks outside the hive such as foraging. Recently it has been shown that the higher developmenta

  10. Modeling and Performance Analysis to Predict the Behavior of a Divisible Load Application in a Cloud Computing Environment

    Directory of Open Access Journals (Sweden)

    Leila Ismail

    2012-05-01

    Full Text Available Cloud computing is an emerging technology where IT resources are virtualized to users as a set of a unified computing resources on a pay per use basis. The resources are dynamically chosen to satisfy a user Service Level Agreement and a required level of performance. Divisible load applications occur in many scientific and engineering applications and can easily be mapped to a Cloud using a master-worker pattern. However, those applications pose challenges to obtain the required performance. We model divisible load applications tasks processing on a set of cloud resources. We derive a novel model and formulas for computing the blocking probability in the system. The formulas are useful to analyze and predict the behavior of a divisible load application on a chosen set of resources to satisfy a Service Level Agreement before the implementation phase, thus saving time and platform energy. They are also useful as a dynamic feedback to a cloud scheduler for optimal scheduling. We evaluate the model in a set of illustrative scenarios.

  11. Complete budding and asymmetric division of primitive model cells to produce daughter vesicles with different interior and membrane compositions.

    Science.gov (United States)

    Andes-Koback, Meghan; Keating, Christine D

    2011-06-22

    Asymmetric cell division is common in biology and plays critical roles in differentiation and development. Unicellular organisms are often used as model systems for understanding the origins and consequences of asymmetry during cell division. Although basic as compared to mammalian cells, these are already quite complex. We report complete budding and asymmetric fission of very simple nonliving model cells to produce daughter vesicles that are chemically distinct in both interior and membrane compositions. Our model cells are based on giant lipid vesicles (GVs, 10-30 μm) encapsulating a polyethylene glycol (PEG)/dextran aqueous two-phase system (ATPS) as a crowded and compartmentalized cytoplasm mimic. Ternary lipid compositions were used to provide coexisting micrometer-scale liquid disordered (L(d)) and liquid ordered (L(o)) domains in the membranes. ATPS-containing vesicles formed buds when sucrose was added externally to provide increased osmotic pressure, such that they became not only morphologically asymmetric but also asymmetric in both their interior and their membrane compositions. Further increases in osmolality drove formation of two chemically distinct daughter vesicles, which were in some cases connected by a lipid nanotube (complete budding), and in others were not (fission). In all cases, separation occurred at the aqueous-aqueous phase boundary, such that one daughter vesicle contained the PEG-rich aqueous phase and the other contained the dextran-rich aqueous phase. PEGylated lipids localized in the L(o) domain resulted in this membrane domain preferentially coating the PEG-rich bud prior to division, and subsequently the PEG-rich daughter vesicle. Varying the mole ratio of lipids resulted in excess surface area of L(o) or L(d) membrane domains such that, upon division, this excess portion was inherited by one of the daughter vesicles. In some cases, a second "generation" of aqueous phase separation and budding could be induced in these daughter

  12. Single and multiple object tracking using log-euclidean Riemannian subspace and block-division appearance model.

    Science.gov (United States)

    Hu, Weiming; Li, Xi; Luo, Wenhan; Zhang, Xiaoqin; Maybank, Stephen; Zhang, Zhongfei

    2012-12-01

    Object appearance modeling is crucial for tracking objects, especially in videos captured by nonstationary cameras and for reasoning about occlusions between multiple moving objects. Based on the log-euclidean Riemannian metric on symmetric positive definite matrices, we propose an incremental log-euclidean Riemannian subspace learning algorithm in which covariance matrices of image features are mapped into a vector space with the log-euclidean Riemannian metric. Based on the subspace learning algorithm, we develop a log-euclidean block-division appearance model which captures both the global and local spatial layout information about object appearances. Single object tracking and multi-object tracking with occlusion reasoning are then achieved by particle filtering-based Bayesian state inference. During tracking, incremental updating of the log-euclidean block-division appearance model captures changes in object appearance. For multi-object tracking, the appearance models of the objects can be updated even in the presence of occlusions. Experimental results demonstrate that the proposed tracking algorithm obtains more accurate results than six state-of-the-art tracking algorithms.

  13. Wavelength Division Multiplexing Passive Optical Network modeling Using Optical System Simulator

    Directory of Open Access Journals (Sweden)

    Nahla Abdulrahman Hussain

    2015-09-01

    Full Text Available Due to the continuing demand for larger bandwidth, the optical transport becoming general in the access network. Using optical fiber technologies, the communications infrastructure becomes powerful, providing very high speeds to transfer a high capacity of data. Existing telecommunications infrastructures is currently widely used Passive Optical Network that apply Wavelength Division Multiplexing (WDM and is awaited to play an important role in the future Internet supporting a large diversity of services and next generation networks. This paper presents a design of WDM-PON network, the simulation and analysis of transmission parameters in the Optisystem 7.0 environment for bidirectional traffic. The simulation shows the behavior of optical fiber links when the signal passes through all the components such as optical fiber, splitters, multiplexers then find a good quality of signal in all receivers. The system performance is presented through various parameters such as BER analyzer and the Eye Diagram.

  14. A model for incorporating computation without changing the course: An example from middle-division classical mechanics

    Science.gov (United States)

    Caballero, Marcos D.; Pollock, Steven J.

    2014-03-01

    Although much of the research done by modern physicists would be impossible without the use of computers, today's physics curricula do not generally reflect their importance and utility. To more tightly connect undergraduate preparation with professional practice, we integrated computational instruction into middle-division classical mechanics at the University of Colorado Boulder. Our model for integration works with the constraints of faculty who do not specialize in computation by placing a strong emphasis on an adaptable curriculum. It also includes the construction of learning goals and the design of activities consistent with those goals, including assessment of student computational fluency. We present critiques of our model as we work to develop an effective and sustainable model for computational instruction in the undergraduate curriculum.

  15. An Application of the PMI Model at the System Level: Evaluation of a Division in Central Administration.

    Science.gov (United States)

    Bland, June D.

    Each of the divisions of the Office of Educational Accountability in the District of Columbia Public Schools was required to submit an evaluation design that would be used to measure division accomplishments at the end of the school year. Since the Division of Research and Evaluation had already completed the development of the Planning,…

  16. Maryland State Police Aviation Division. A model emergency medical system for our nation.

    Science.gov (United States)

    Edlich, Richard F; Wish, John R

    2004-01-01

    This collective review has the following purposes. First we will describe each of the components of the Maryland State Police Aviation Division. We will then provide detailed information about the Atlas and Database of Air Medical Services (ADAMS) compiled by the center for transportation and injury research (Buffalo, New York) in alliance with the Association of Air Medical Services (Alexandria, Virginia) that provides a unique opportunity for each state to evaluate the comprehensive nature of their air medical services. The concept "the golden hour" has been molded into the world's premier public service aviation unit, which has proudly served the citizens of Maryland for over 24 years. This effort was initially made possible through a cooperative effort between the Maryland State Police Aviation Division and Dr. R Adams Cowley at the University of Maryland Hospital as a public service to the citizens of the state. This arrangement added a unique, economical, and life-saving component to the regionalized Emergency Medical Services and Critical Care system coordinated by the Maryland Institute for Emergency Medical Services Systems (MIESS). The Maryland State Police Aviation Division has four components: (1) aircraft, (2) state troopers, (3) system communications (SYSCOM) center, and (4) level I adult and pediatric trauma centers, as well as a regional burn center. ADAMS is a compilation of information of Air Medical Services in the United States to respond to traumas and other emergencies. Specifically, ADAMS provides descriptive and geographic information on Air Medical Service base locations, communication centers, rotor wing (RW) assets, and the major hospitals and transports that receive scene transports. The database includes all types of provider organizations including nonprofit, commercial, and public service (fire, police) air medical service providers, as well as several military units that routinely provide transport in remote areas. ADAMS provides

  17. Efektivitas Model Pembelajaran Kooperatif Tipe Student Team Achievement Division (STAD yang Dimodifikasi dengan Tutor Sebaya ditinjau dari Kecerdasan Majemuk Siswa.

    Directory of Open Access Journals (Sweden)

    Dwi Mei Heni

    2014-01-01

    Full Text Available The Effectiveness Model of Modified Student Team Achievement Division (STAD Type of Cooperative Learning with Peer tutoring Viewed from the Student’s Multiple Intelligences. This research was conducted to find out: Which learning model giving better student learning achievement, STAD or modified STAD with peer tutoring. The research population was all XI graders of Vocational School (SMK throughout Bojonegoro Regency in the school year of 2011/2012. The sampling used was stratified cluster random sampling and then chosen three schools namely SMKN 1 Bojonegoro, SMK Muhammadiyah 2 Sumberrejo, and SMK PGRI 3 Bojonegoro. Technique of analyzing data used was two-way anava 2x3 with different cell. In this research, it can be concluded that The student with the modified STAD type of cooperative learning with peer tutoring have better mathematics learning achievement than the students with STAD type of cooperative learning.   Keywords : Modified STAD with peer tutoring, Multiple Intelligences, Mathematics Learning Achievement

  18. Fighting Divisions

    Science.gov (United States)

    1945-12-01

    when it hit the beaches of Morotai to open the drive that later led to the liberation of the Philippines, its Doughboys were alternately whistling...the Dixie Division sailed from Maffin Bay for the reconquest of Morotai , and on the 15th of the month hit the beaches of this Dutch island, less than...quickly secured a beachhead and by noon of D-day had seized Pitoe Airdrome. Morotai gave our forces control of the Halma- hera Sea and cut off 20,000

  19. Physics Learning using Inquiry-Student Team Achievement Division (ISTAD and Guided Inquiry Models Viewed by Students Achievement Motivation

    Directory of Open Access Journals (Sweden)

    S. H. Sulistijo

    2017-04-01

    Full Text Available This study aims to determine the differences in learning outcomes of between students that are given the Physics learning models of Inquiry-Student Team Achievement Division (ISTAD and guided inquiry, between students who have high achievement motivation and low achievement motivation. This study was an experimental study with a 2x2x2 factorial design. The study population was the students of class X of SMAN 1 Toroh Grobogan of academic year 2016/2017. Samples were obtained by cluster random sampling technique consists of two classes, class X IPA 3 is used as an experimental class using ISTAD model and class X IPA 4 as the control class using guided inquiry model. Data collection techniques using test techniques for learning outcomes, and technical questionnaire to obtain the data of students' achievement motivation. Analysis of data using two-way ANOVA. The results showed that: (1 there is a difference between the learning outcomes of students with the ISTAD Physics models and with the physics model of guided inquiry. (2 There are differences in learning outcomes between students who have high achievement motivation and low achievement motivation. (3 There is no interaction between ISTAD and guided inquiry Physics models learning and achievement motivation of students.

  20. KEEFEKTIVAN MODEL PEMBELAJARAN STUDENT TEAMS ACHIEVEMENT DIVISION (STAD PADA PEMBELAJARAN EKONOMI BERBASIS KONSTRUKTIVIS TERHADAP HASIL BELAJAR SISWA

    Directory of Open Access Journals (Sweden)

    Asep Amaludin

    2016-01-01

    Full Text Available Learning is a process of changing the behavior through experience and training. The changing of behavior involves knowledge, skills, attitudes and even all aspects of the organism or individual himself. Unfortunately, many students have difficulty in understanding the abstract concepts of a subject. Therefore, we need the alternative learning model to overcome the difficulties in learning. One of the learning models is Student Team Achievement Division (STAD learning model. STAD model is a cooperative learning model encouraging students to actively discover knowledge through the skills process. The objective of this study is to determine the average difference of students’ learning outcomes through cooperative learning model with STAD type and the expository model on the subject material of Market Price Formation. The population of this study was all VIII Classes of SMP Negeri 1 Randudongkal in the academic year of 2007/2008. There were 7 classes consisted of 292 students. Samples are taken randomly, the first group was VIIIC students as the experimental group using STAD learning model, whereas the second group was students in VIIID class as the control group. Data was collected by test method, and then analyzed by the mean difference test. The results showed that there was a significant mean difference in students’ learning outcomes. The average score for experimental group was 75.93 and for the control group was only 71.36. Based on this study, it is suggested to use STAD learning model based on constructivism in teaching and learning process because it can encourage students to be active with their own skills. 

  1. Winterkill indicator model, Crop Condition Assessment Division (CCAD) data base interface driver, user's manual

    Science.gov (United States)

    Hansen, R. F. (Principal Investigator)

    1981-01-01

    Instructions are given for using the Winterkill indicator model CCAD data base interface driver. The purpose of the system is to interface the Winterkill Indicator Model with the CCAD operational data base. The interface driver routine decides what meteorological stations should be processed and calls the proper subroutines to process the stations.

  2. Wheat stress indicator model, Crop Condition Assessment Division (CCAD) data base interface driver, user's manual

    Science.gov (United States)

    Hansen, R. F. (Principal Investigator)

    1981-01-01

    The use of the wheat stress indicator model CCAD data base interface driver is described. The purpose of this system is to interface the wheat stress indicator model with the CCAD operational data base. The interface driver routine decides what meteorological stations should be processed and calls the proper subroutines to process the stations.

  3. Incorporating learning goals about modeling into an upper-division physics laboratory experiment

    Science.gov (United States)

    Zwickl, Benjamin M.; Finkelstein, Noah; Lewandowski, H. J.

    2014-09-01

    Implementing a laboratory activity involves a complex interplay among learning goals, available resources, feedback about the existing course, best practices for teaching, and an overall philosophy about teaching labs. Building on our previous work, which described a process of transforming an entire lab course, we now turn our attention to how an individual lab activity on the polarization of light was redesigned to include a renewed emphasis on one broad learning goal: modeling. By using this common optics lab as a concrete case study of a broadly applicable approach, we highlight many aspects of the activity development and show how modeling is used to integrate sophisticated conceptual and quantitative reasoning into the experimental process through the various aspects of modeling: constructing models, making predictions, interpreting data, comparing measurements with predictions, and refining models. One significant outcome is a natural way to integrate an analysis and discussion of systematic error into a lab activity.

  4. Modeling interchannel four-wave mixing for 8-Ary modulated dense wavelength division multiplexing systems over dispersion map

    Science.gov (United States)

    Du, Jianxin; Shen, Ninghang; Xu, Yue

    2016-08-01

    Semianalytic models are developed to deterministically calculate the variances of degenerate and nondegenerate four-wave mixing (FWM) noises for dispersion-managed dense wavelength division multiplexing (DWDM) systems with 8-Ary modulations [i.e., 8-level amplitude- and differential phase-shift keying (8APSK) and constant-amplitude optical differential 8-level phase-shift keying (D8PSK)]. The semianalytic models include various important propagation effects for exact numerical results. A 5.28-Tb/s (40-Gs/s/ch) 100-GHz-spaced 33-channel DWDM system with a dispersion map is then numerically analyzed by using the newly derived semianalytic models. It is numerically validated that FWM impacts coming from 8APSK pump channels are more severe than those coming from D8PSK ones, where pump channels denote the channels whose energies are transferred to a probe channel through the FWM process. The numerical results show that although FWM tolerance of a central channel with 8APSK is worse than that with D8PSK, a central channel with 8APSK is still superior to that with D8PSK when some linear noises and FWM noise are simultaneously taken into account for our given system conditions, which is mainly attributed to a relatively larger minimum Euclidean distance for the 8APSK constellation than the D8PSK one.

  5. Mathematical models of tissue stem and transit target cell divisions and the risk of radiation- or smoking-associated cancer.

    Science.gov (United States)

    Little, Mark P; Hendry, Jolyon H

    2017-02-01

    There is compelling biological data to suggest that cancer arises from a series of mutations in single target cells, resulting in defects in cell renewal and differentiation processes which lead to malignancy. Because much mutagenic damage is expressed following cell division, more-rapidly renewing tissues could be at higher risk because of the larger number of cell replications. Cairns suggested that renewing tissues may reduce cancer risk by partitioning the dividing cell populations into lineages comprising infrequently-dividing long-lived stem cells and frequently-dividing short-lived daughter transit cells. We develop generalizations of three recent cancer-induction models that account for the joint maintenance and renewal of stem and transit cells, also competing processes of partially transformed cell proliferation and differentiation/apoptosis. We are particularly interested in using these models to separately assess the probabilities of mutation and development of cancer associated with "spontaneous" processes and with those linked to a specific environmental mutagen, specifically ionizing radiation or cigarette smoking. All three models demonstrate substantial variation in cancer risks, by at least 20 orders of magnitude, depending on the assumed number of critical mutations required for cancer, and the stem-cell and transition-cell mutation rates. However, in most cases the conditional probabilities of cancer being mutagen-induced range between 7-96%. The relative risks associated with mutagen exposure compared to background rates are also stable, ranging from 1.0-16.0. Very few cancers, generally Little difference is made to relative risks if competing processes of proliferation and differentiation in the partially transformed stem and transit cell population are allowed for, nor is any difference made if one assumes that transit cells require an extra mutation to confer malignancy from the number required by stem cells. The probability of a cancer

  6. Educational Transformation in Upper-Division Physics: The Science Education Initiative Model, Outcomes, and Lessons Learned

    Science.gov (United States)

    Chasteen, Stephanie V.; Wilcox, Bethany; Caballero, Marcos D.; Perkins, Katherine K.; Pollock, Steven J.; Wieman, Carl E.

    2015-01-01

    In response to the need for a scalable, institutionally supported model of educational change, the Science Education Initiative (SEI) was created as an experiment in transforming course materials and faculty practices at two institutions--University of Colorado Boulder (CU) and University of British Columbia. We find that this departmentally…

  7. An Economic Analysis Model of the Classification of Needs in Level Division

    Institute of Scientific and Technical Information of China (English)

    WEN Xiao-zheng

    2004-01-01

    Because there is a vague distinction respectively between the measurable components and mutual replacement, subjective comments and objective comments in the theories given by Maslow and Orldever, the author once offered his point on the four-level classification of needs. In order to interpret the mutual relation of the four levels, this paper mainly aims at offering an appropriate support of mathematical model and technical explanation. It offers an economic analysis and explanation of human needs qualitatively and quantitatively.

  8. Mathematical model of naive T cell division and survival IL-7 thresholds

    Directory of Open Access Journals (Sweden)

    Carmen eMolina-Paris

    2013-12-01

    Full Text Available We develop a mathematical model to describe the homeostasis of naive T~cells in the peripheral immune system of ageing humans, incorporating thymic output and the availability of interleukin-7 (IL-7. The model is formulated as three ordinary differential equations: two describe T~cell numbers, in a resting state and progressing through the cell cycle. The third is introduced to describe changes in IL-7 availability. Thymic output is a decreasing function of time, representative of thymic atrophy found in ageing humans. Each T~cell is assumed to possess two interleukin-7 receptor (IL-7R signalling thresholds: a survival threshold and a second, higher, proliferation threshold. If the IL-7R signalling strength is below its survival threshold, a cell may undergo apoptosis. When the signalling strength is above the survival threshold, but below the proliferation threshold, the cell survives but does not divide. Signalling strength above the proliferation threshold enables entry into cell cycle. Assuming that individual cell thresholds are log-normally distributed, we derive population-average rates for apoptosis and entry into cell cycle. We have analysed the adiabatic change in homeostasis as thymic output decreases. With a parameter set representative of a healthy individual, the model predicts a unique equilibrium number of T~cells. In a parameter range representative of persistent virus or bacterial infection, where naive T~cell survival is impaired, a decrease in thymic output may result in the collapse of the naive T~cell repertoire.

  9. PERSONNEL DIVISION BECOMES HUMAN RESOURCES DIVISION

    CERN Document Server

    Division des ressources humaines

    2000-01-01

    In the years to come, CERN faces big challenges in the planning and use of human resources. At this moment, Personnel (PE) Division is being reorganised to prepare for new tasks and priorities. In order to accentuate the purposes of the operation, the name of the division has been changed into Human Resources (HR) Division, with effect from 1st January 2000. Human Resources DivisionTel.73222

  10. Division of Labor

    KAUST Repository

    Oke, Muse

    2014-09-12

    The first assignment of DNA polymerases at the eukaryotic replication fork was possible after the in vitro reconstitution of the simian virus 40 (SV40) replication system. In this system, DNA polymerase α (Pol α) provides both leading and lagging strands with RNA-DNA primers that are extended by DNA polymerase δ (Pol δ). Extrapolating the architecture of the replication fork from the SV40 model system to an actual eukaryotic cell has been challenged by the discovery of a third DNA polymerase in Saccharomyces cerevisiae, DNA polymerase ε (Pol ε). A division of labor has been proposed for the eukaryotic replication fork whereby Pol ε replicates the leading strand and Pol δ replicates the lagging strand. However, an alternative model of unequal division of labor in which Pol δ can still participate in leading-strand synthesis is plausible.

  11. Division of household tasks and financial management

    NARCIS (Netherlands)

    Antonides, G.

    2011-01-01

    Both the standard economic model and bargaining theory make predictions about financial management and the division of household labor between household partners. Using a large Internet survey, we have tested several predictions about task divisions reported by Dutch household partners. The division

  12. Modeling, Analysis, and Simulation of an Optical Time-Division Multiple- Access Network Architecture

    Science.gov (United States)

    1993-11-01

    equation model, the overall system has to be simulated at a rate of l/h. The efficiency improvement of the ANN implementation over the LM method then...From the above equations we see that the ANN implementation is clearly more ef- ficient in the first case, while in the latter cases it still has...method and time step, as opposed to the ANN implementation whose behavior is based on the anticipated "generalization" of the network’s training. 24

  13. The Modelling of Reasoning and Justification Methods in the Teaching of Fraction Division at Year 4 Level in Vietnam

    Science.gov (United States)

    Norton, Stephen; Thao, Do Thi Phurong; Duy, Mai The

    2014-01-01

    Stephen Norton, Do Thi Phurong Thao and Mai The Duy provide an interesting insight into the teaching of fraction division in Vietnam. The article highlights one of the many teaching strategies available to teachers for building fraction concepts.

  14. Interorganizational Knowledge Division Decision Model Based on Cooperative Innovation of Supply Chain System

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2014-01-01

    Full Text Available Within interorganizational cooperative innovation of construction supply chain system, the achievement of project value-adding could be reflected by several factors, such as project-based organizational effect level, and the relationship between project cooperative innovation objectives. In this paper, based on the assumption of equal cooperation between project-based organizations, we selected the knowledge cooperation between the owner and contractor in construction supply chain system as research object. From the perspective of maximizing project value-adding and the relationship of effort cost between knowledge input and innovation stage in consideration, we established the knowledge collaborative incentive model for interorganizational cooperative innovation of construction supply chain system and proposed the first-order and second-order approaches. Then we conducted the digital simulation and example analysis, its results showed that if the owner has the capability to achieve project value-adding in knowledge cooperation, he would adopt a part commissioned way. Otherwise, a fully commissioned way would be better.

  15. A Model to Investigate Performance of Orthogonal Frequency Code Division Multiplexing

    Directory of Open Access Journals (Sweden)

    Ellsa Fitria Sari

    2012-07-01

    Full Text Available OFCDM is an attractive multiple access scheme for high data rate application in Fourth-generation (4G wireless communication system. Previously, several researches were only investigated the performance of OFCDM based on variable spreading factor. However, there are several system parameters may affected the performance of OFCDM. Therefore, this paper investigates the impact of several parameters on the performance system of OFCDMA over Rayleigh Fading channel as a realistic channel in wireless communications.The simulation system model of OFCDM is introduced. The computer simulation is developed by using MATLAB programming in order to show the impact of several parameters for OFCDM’s performance including number of carriers, size of symbol, symbol rate, bit rate, size of guard interval and spreading factor. The simulation results show that the higher number of carriers, larger size of symbol, higher symbol rate, higher bit rate and larger spreading factor are giving the better system’s performance in terms of Bit Error Rate (BER. However, the larger guard interval is giving the worst system’s performance.So all the parameters should be considered in the implementation of OFCDM for the 4G wireless communication system.

  16. A long-term evaluation of treated Class II division 2 malocclusions: a retrospective study model analysis.

    Science.gov (United States)

    Canut, J A; Arias, S

    1999-08-01

    Pre-treatment, end of treatment, and post-retention study models of 30 subjects with a Class II division 2 malocclusion were assessed, after a period of at least 3 years, in order to evaluate the long-term changes in occlusion, alignment, and arch dimensions. Molar relationship correction was found to be stable after retention. There were no variables which could be used to establish a prognosis of vertical stability. Over-correction of overbite was seen to relapse. Ten per cent of the cases showed unacceptable anterior maxillary irregularities after retention. Mandibular arch width and length usually showed a decrease after retention. An increase in lower intercanine width and arch length achieved by orthodontic treatment always relapsed. This relapse was associated with post-retention mandibular irregularity and crowding. Nine cases (30 per cent) showed an unacceptable degree of mandibular irregularity after retention. Pre-treatment crowding in the mandible showed a relationship with post-retention lower irregularity and crowding. There was a correlation between the number of years which had elapsed after retention, overbite relapse and post-retention mandibular irregularity.

  17. The simulation model of growth and cell divisions for the root apex with an apical cell in application to Azolla pinnata.

    Science.gov (United States)

    Piekarska-Stachowiak, Anna; Nakielski, Jerzy

    2013-12-01

    In contrast to seed plants, the roots of most ferns have a single apical cell which is the ultimate source of all cells in the root. The apical cell has a tetrahedral shape and divides asymmetrically. The root cap derives from the distal division face, while merophytes derived from three proximal division faces contribute to the root proper. The merophytes are produced sequentially forming three sectors along a helix around the root axis. During development, they divide and differentiate in a predictable pattern. Such growth causes cell pattern of the root apex to be remarkably regular and self-perpetuating. The nature of this regularity remains unknown. This paper shows the 2D simulation model for growth of the root apex with the apical cell in application to Azolla pinnata. The field of growth rates of the organ, prescribed by the model, is of a tensor type (symplastic growth) and cells divide taking principal growth directions into account. The simulations show how the cell pattern in a longitudinal section of the apex develops in time. The virtual root apex grows realistically and its cell pattern is similar to that observed in anatomical sections. The simulations indicate that the cell pattern regularity results from cell divisions which are oriented with respect to principal growth directions. Such divisions are essential for maintenance of peri-anticlinal arrangement of cell walls and coordinated growth of merophytes during the development. The highly specific division program that takes place in merophytes prior to differentiation seems to be regulated at the cellular level.

  18. The Battlefield Environment Division Modeling Framework (BMF). Part 1: Optimizing the Atmospheric Boundary Layer Environment Model for Cluster Computing

    Science.gov (United States)

    2014-02-01

    2.1 Design of BMF The BMF design loosely follows the Model-View-Controller ( MVC ) design pattern. While some design considerations have been...Interface MVC Model-View-Controller NetCDF Network Common Data Form SIMPLE semi-implicit method for pressure-linked equations SIMPLER semi-implicit method

  19. The Indoctrination Division: A Model for Effective Integration of First-Term Enlisted Personnel into the Aircraft Carrier Organization

    Science.gov (United States)

    1976-06-01

    be failing. Premarital intercourse is fairly common among the adolescent population and is more tolerated by society in general than it was genera...indoctrinee should be assigned a sponsor, or "buddy," in the division to which he will be assigned. This peer-sponsor is a previously screened

  20. A Hybrid Forecasting Model Based on Bivariate Division and a Backpropagation Artificial Neural Network Optimized by Chaos Particle Swarm Optimization for Day-Ahead Electricity Price

    Directory of Open Access Journals (Sweden)

    Zhilong Wang

    2014-01-01

    Full Text Available In the electricity market, the electricity price plays an inevitable role. Nevertheless, accurate price forecasting, a vital factor affecting both government regulatory agencies and public power companies, remains a huge challenge and a critical problem. Determining how to address the accurate forecasting problem becomes an even more significant task in an era in which electricity is increasingly important. Based on the chaos particle swarm optimization (CPSO, the backpropagation artificial neural network (BPANN, and the idea of bivariate division, this paper proposes a bivariate division BPANN (BD-BPANN method and the CPSO-BD-BPANN method for forecasting electricity price. The former method creatively transforms the electricity demand and price to be a new variable, named DV, which is calculated using the division principle, to forecast the day-ahead electricity by multiplying the forecasted values of the DVs and forecasted values of the demand. Next, to improve the accuracy of BD-BPANN, chaos particle swarm optimization and BD-BPANN are synthesized to form a novel model, CPSO-BD-BPANN. In this study, CPSO is utilized to optimize the initial parameters of BD-BPANN to make its output more stable than the original model. Finally, two forecasting strategies are proposed regarding different situations.

  1. Modeling and characterization of a few-mode EDFA supporting four mode groups for mode division multiplexing.

    Science.gov (United States)

    Le Cocq, Guillaume; Bigot, Laurent; Le Rouge, Antoine; Bigot-Astruc, Marianne; Sillard, Pierre; Koebele, Clemens; Salsi, Massimilliano; Quiquempois, Yves

    2012-11-19

    Numerical and experimental study of a Few-Mode (FM) Erbium Doped Fiber Amplifier (EDFA) suitable for mode division multiplexing (MDM) is reported. Based on numerical simulations, a Few-Mode Erbium Doped Fiber (FM-EDF) has been designed to amplify four mode groups and to equally amplify LP11 and LP21 mode groups with gains greater than 20 dB and with a differential modal gain of less than 1 dB. Experimental results confirmed the simulations with a good concordance. This modal gain equalization is obtained by tailoring the erbium spatial distribution in the fiber core with a ring-shaped profile.

  2. Competitive Equilibria in Economies with Multiple Divisible and Multiple Divisible Commodities

    NARCIS (Netherlands)

    Koshevoy, G.A.; Talman, A.J.J.

    2002-01-01

    In this paper we consider a general equilibrium model with a finite number of divisible and indivisible commodities.In models with indivisibilities it is typically assumed that there is only one perfectly divisible good, which serves as money.The presence of money in the model is used to transfer

  3. Competitive Equilibria in Economies with Multiple Divisible and Multiple Divisible Commodities

    NARCIS (Netherlands)

    Koshevoy, G.A.; Talman, A.J.J.

    2002-01-01

    In this paper we consider a general equilibrium model with a finite number of divisible and indivisible commodities.In models with indivisibilities it is typically assumed that there is only one perfectly divisible good, which serves as money.The presence of money in the model is used to transfer th

  4. GIS-based revised main function division model in the rural-urban continuum: as a case study in Tianjin, China

    Science.gov (United States)

    Chang, Qing; He, Huanle; Li, Xue

    2011-02-01

    The usage of mutual pattern-function matrix based on Geographical Information System (GIS) provides an approach to revise the traditional main function division that lacks the transition between development and protection, especially for the rural-urban fringe areas where the communications of the matter, energy and information between different ecosystems are frequent and complex. In the paper, this GIS-based revised main function division model consists of landscape connectivity evaluation by Cost distance model, agro-suitability analysis by Grid module and mutual coupling matrix mapping by Raster calculator. All these parametric evaluations will help in squeezing/ decreasing the gap between development patterns and ecology functions in the rural-urban fringes. These concepts were implemented in the Xiqing district of Tianjin in China. The results revealed that the ecological protection zone, ecological restoration zone, limited development zone, key development zone and the optimized development zone are gradually shifted from west to east, which supported the actually spatial development rule of Tianjin city which provides a guideline for urban green space planning of Xiqing District.

  5. Division: The Sleeping Dragon

    Science.gov (United States)

    Watson, Anne

    2012-01-01

    Of the four mathematical operators, division seems to not sit easily for many learners. Division is often described as "the odd one out". Pupils develop coping strategies that enable them to "get away with it". So, problems, misunderstandings, and misconceptions go unresolved perhaps for a lifetime. Why is this? Is it a case of "out of sight out…

  6. Division: The Sleeping Dragon

    Science.gov (United States)

    Watson, Anne

    2012-01-01

    Of the four mathematical operators, division seems to not sit easily for many learners. Division is often described as "the odd one out". Pupils develop coping strategies that enable them to "get away with it". So, problems, misunderstandings, and misconceptions go unresolved perhaps for a lifetime. Why is this? Is it a case of "out of sight out…

  7. Arithmetic of Division Fields

    CERN Document Server

    Brumer, Armand

    2011-01-01

    We study the arithmetic of division fields of semistable abelian varieties A over the rationals. The Galois group of the 2-division field of A is analyzed when the conductor is odd and squarefree. The irreducible semistable mod 2 representations of small conductor are determined under GRH. These results are used in "Paramodular abelian varieties of odd conductor," arXiv:1004.4699.

  8. On infinitely divisible semimartingales

    DEFF Research Database (Denmark)

    Basse-O'Connor, Andreas; Rosiński, Jan

    2015-01-01

    are strictly representable due to Hida's multiplicity theorem, the classical Stricker's theorem follows from our result. Another consequence is that the question when an infinitely divisible process is a semimartingale can often be reduced to a path property, when a certain associated infinitely divisible...

  9. Atmospheric and Geophysical Sciences Division Program Report, 1988--1989

    Energy Technology Data Exchange (ETDEWEB)

    1990-06-01

    In 1990, the Atmospheric and Geophysical Sciences Division begins its 17th year as a division. As the Division has grown over the years, its modeling capabilities have expanded to include a broad range of time and space scales ranging from hours to decades and from local to global. Our modeling is now reaching out from its atmospheric focus to treat linkages with the oceans and the land. In this report, we describe the Division's goal and organizational structure. We also provide tables and appendices describing the Division's budget, personnel, models, and publications. 2 figs., 1 tab.

  10. Divisible ℤ-modules

    Directory of Open Access Journals (Sweden)

    Futa Yuichi

    2016-03-01

    Full Text Available In this article, we formalize the definition of divisible ℤ-module and its properties in the Mizar system [3]. We formally prove that any non-trivial divisible ℤ-modules are not finitely-generated.We introduce a divisible ℤ-module, equivalent to a vector space of a torsion-free ℤ-module with a coefficient ring ℚ. ℤ-modules are important for lattice problems, LLL (Lenstra, Lenstra and Lovász base reduction algorithm [15], cryptographic systems with lattices [16] and coding theory [8].

  11. Control of oriented cell division in the Arabidopsis embryo

    NARCIS (Netherlands)

    Dop, van M.; Liao, C.Y.; Weijers, D.

    2015-01-01

    Multicellular plant development requires strict control of cell division orientation. A key unanswered question is how developmental regulators interact with the generic cell division machinery to trigger oriented divisions. We discuss the Arabidopsis embryo as a model for addressing this question.

  12. Underwater Sound Reference Division

    Data.gov (United States)

    Federal Laboratory Consortium — The Underwater Sound Reference Division (USRD) serves as the U.S. standardizing activity in the area of underwater acoustic measurements, as the National Institute...

  13. Underwater Sound Reference Division

    Data.gov (United States)

    Federal Laboratory Consortium — The Underwater Sound Reference Division (USRD) serves as the U.S. standardizing activity in the area of underwater acoustic measurements, as the National Institute...

  14. On Geometric Infinite Divisibility

    OpenAIRE

    Sandhya, E.; Pillai, R. N.

    2014-01-01

    The notion of geometric version of an infinitely divisible law is introduced. Concepts parallel to attraction and partial attraction are developed and studied in the setup of geometric summing of random variables.

  15. 77 FR 41986 - Division of Nursing, Public Health Nursing Community Based Model of PHN Case Management Services

    Science.gov (United States)

    2012-07-17

    ...), Community Based Model of Public Health Nursing Case Management Services. This program is authorized under... management model that utilizes the PHN as a case manager. Research indicates nursing case management is a..., communication and monitoring. The goals and outcomes of the PHN case management model are early detection...

  16. Multiscale Modeling for Fracture Zone with Detailed Division%裂隙矿段多尺度精细分区模型构建

    Institute of Scientific and Technical Information of China (English)

    胡建华; 胡昱; 周科平; 何川

    2015-01-01

    With the True Reflection Tomography( TRT) 3D image processed by slicing, the generated data was exported and coupled into 3DMine software, resulting in a local reflection coefficient of fracture zone. The principle for data exporting and method for model construction were all presented. Based on the digital model of the deposit, a multiscale modeling for fracture zone with detailed division was obtained. Then, a further analysis was conducted for such multiscale modeling . Result showed that the process of slicing TRT image can give a classification of degree of rock mass damage in fracture zone. Based on the digital processing, a model with detailed rock mass damage can be constructed with the classification of reflection coefficient, which is also a multiscale model from the perspective of space, beneficial for processing and analyzing the difference in each mineralized zone. The application into engineering project also indicated such multiscale modeling with detailed division can meet the requirement for regional mining and security in underground mine.%利用TRT6000超前探测数据与3DMine软件耦合,以切片导出数据的方法,获取裂隙矿段的局地反射系数并确立了数据导出原则和模型构建方法,在矿床数字模型基础上,建立裂隙矿段多尺度精细分区模型。对TRT6000数据导出及在3DMine中建立多尺度精细分区模型的方法进行了研究,并对构建的多尺度精细分区模型进行了进一步分析,结果表明:切片数据处理方法可以建立裂隙矿段不同破损程度岩体的分级并进行精细数字化处理;利用反射系数的分级,实现了岩体破损精细建模,有利于不同矿段的差异化处置与分析,是一种跨空间的多尺度模型。工程应用表明精细化、多尺度模型满足了区域采矿与局地安全的需要。

  17. Asymmetric stem cell division: lessons from Drosophila.

    Science.gov (United States)

    Wu, Pao-Shu; Egger, Boris; Brand, Andrea H

    2008-06-01

    Asymmetric cell division is an important and conserved strategy in the generation of cellular diversity during animal development. Many of our insights into the underlying mechanisms of asymmetric cell division have been gained from Drosophila, including the establishment of polarity, orientation of mitotic spindles and segregation of cell fate determinants. Recent studies are also beginning to reveal the connection between the misregulation of asymmetric cell division and cancer. What we are learning from Drosophila as a model system has implication both for stem cell biology and also cancer research.

  18. Effects of Role Division, Interaction, and Shared Mental Model on Team Performance in Project-Based Learning Environment

    Science.gov (United States)

    Jo, Il-Hyun

    2011-01-01

    The purpose of this study was to investigate the cognitive mechanism of project-based learning teams of college students on the basis of the Shared Mental Model (SMM) theory. The study participants were 237 female college students in Korea organized into 51 project teams. To test the study hypotheses, a structural equation modeling was employed.…

  19. Effects of Role Division, Interaction, and Shared Mental Model on Team Performance in Project-Based Learning Environment

    Science.gov (United States)

    Jo, Il-Hyun

    2011-01-01

    The purpose of this study was to investigate the cognitive mechanism of project-based learning teams of college students on the basis of the Shared Mental Model (SMM) theory. The study participants were 237 female college students in Korea organized into 51 project teams. To test the study hypotheses, a structural equation modeling was employed.…

  20. The fencing problem and Coleochaete cell division.

    Science.gov (United States)

    Wang, Yuandi; Dou, Mingya; Zhou, Zhigang

    2015-03-01

    The findings in this study suggest that the solution of a boundary value problem for differential equation system can be used to discuss the fencing problem in mathematics and Coleochaete, a green algae, cell division. This differential equation model in parametric expression is used to simulate the two kinds of cell division process, one is for the usual case and the case with a "dead" daughter cell.

  1. Sperner's lemma and fair division

    OpenAIRE

    DAKSKOBLER, LARISA

    2016-01-01

    Fair division is an active research area in Mathematics, Economics, Computer Science, etc. There are many different kinds of fair division problems. These are often named after everyday situations: fair resource allocation, fair cake-cutting, fair chore division, room assignment – rent division, and more. Although many exact and approximative methods for finding fair solutions already exist, the area of fair division still expands and tries to find better solutions for everyday problems. The...

  2. Division algebras and supersymmetry

    CERN Document Server

    Baez, John C

    2009-01-01

    Supersymmetry is deeply related to division algebras. Nonabelian Yang--Mills fields minimally coupled to massless spinors are supersymmetric if and only if the dimension of spacetime is 3, 4, 6 or 10. The same is true for the Green--Schwarz superstring. In both cases, supersymmetry relies on the vanishing of a certain trilinear expression involving a spinor field. The reason for this, in turn, is the existence of normed division algebras in dimensions 1, 2, 4 and 8: the real numbers, complex numbers, quaternions and octonions. Here we provide a self-contained account of how this works.

  3. Power Dissipation in Division

    DEFF Research Database (Denmark)

    Liu, Wei; Nannarelli, Alberto

    2008-01-01

    A few classes of algorithms to implement division in hardware have been used over the years: division by digit-recurrence, by reciprocal approximation by iterative methods and by polynomial approximation. Due to the differences in the algorithms, a comparison among their implementation in terms...... of performance and precision is sometimes hard to make. In this work, we use power dissipation and energy consumption as metrics to compare among those different classes of algorithms. There are no previous works in the literature presenting such a comparison....

  4. A Division-Dependent Compartmental Model for Computing Cell Numbers in CFSE-based Lymphocyte Proliferation Assays

    Science.gov (United States)

    2012-02-12

    based upon the premises of information theory, is found in the Akaike Information Criterion (AIC). Briefly, for models with independent, homoscedastic...we can compute the Akaike weights wr = exp ( −∆r 2 ) ∑ r exp ( −∆r 2 ) . (26) It can be shown (either by likelihood ratio tests or in a Bayesian ...No. 0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing

  5. PERBEDAAN HASIL BELAJAR EKONOMI SISWA YANG MENGGUNAKAN MODEL PEMBELAJARANKOOPERATIFTIPETHINK PAIR SHARE (TPS DENGAN TIPE STUDENT TEAMS ACHIEVEMENT DIVISION(STADSISWA KELAS XI IPS SMAN 11 PADANG

    Directory of Open Access Journals (Sweden)

    Dina Sofianti

    2013-04-01

    Full Text Available The research aims to analyze the difference of learning points by using the cooperative learning models between Think Pair Share (TPS and Student Teams Achievement Division (STAD types of the XI-grade students of IPS SMAN 11 Padang. It is an experimental research. The population of this research is all XI-grade students of IPS SMAN 11 Padang, who were registered in the year 2013-2014. Two samples were selected by using the technique of Purposive Sampling method. The data of this research is primary data, and the data analyses are descriptive and inductive, conducted through t-test by first making tests of normality and homogeneity of both sample variants. Based on the data analyses, it is obtained that the learning points for the experimental class 1 is 76.80 and the experimental class 2 is 65.64 on the average, meaning that Sig 0.018 is smaller than α = 0.05. From the hypothesis tests, tcalc.is 2.444 and ttable is 1.67, so that H0 is rejected, meaning that there is the difference between TPS and STAD. From the results, it is expected that this could provide a solution for the problem of lowering learning points especially in economics subject. Finally, for improving the learning points of economical students, it is suggested for teachers to consider the learning models from Think Pair Share TPS and STAD.

  6. Model Supplay Chain Management dan Perancangan Aplikasi E-SCM pada PT Indofood Sukses Makmur Tbk Bogasari Flour Mills Division

    Directory of Open Access Journals (Sweden)

    Hendry Ang

    2014-03-01

    Full Text Available The purpose of this study is to analyze company business process by determining the appropriate model of supply chain at PT Indofood Sukses Makmur Bogasari and designing the e-SCM system that aims to facilitate the flow of information and products to the company, ranging from suppliers to customers. Research used Porter’s Five Forces analysis, value network analysis, order fulfillment based on the concept of decoupling point, EOQ (Economic Order Quantity inventory model, and the method of designing an e-SCM system with Object Oriented Analysis Design (OOAD. The results of Porter’s Five Forces analysis show that bargaining power of suppliers and competition among similar companies had a strong tendency, while bargaining power of customers, new competitors, and product substitution had a weak tendency in the external environment. In addition, the value chain analysis results show the condition of the company's internal information flows were substandard, especially in the upstream of the business process in the company. Based on the concept of decoupling point, MTS was more appropriate to Bogasari in response to consumer demand. Furthermore, this study also proposed EOQ inventory model so that the company can manage inventory and order better as well as overcome some of the problems such as the uncertainty in the inventory levels of consumer demand and limited raw materials from suppliers. The e-SCM online system application designed with Object Oriented Analysis Design (OOAD is expected to facilitate the flow of information and to integrate its customers and agents in supporting company business process, so the information between suppliers and customers becomes well integrated.

  7. | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  8. On infinitely divisible semimartingales

    DEFF Research Database (Denmark)

    Basse-O'Connor, Andreas; Rosiński, Jan

    2015-01-01

    processes, including linear fractional processes, mixed moving averages, and supOU processes, as particular cases. The proof of the main theorem relies on series representations of jumps of cadlag infinitely divisible processes given in Basse-O'Connor and Rosinski [2013, Ann. Probab. 41(6)] combined...

  9. Solid State Division

    Energy Technology Data Exchange (ETDEWEB)

    Green, P.H.; Watson, D.M. (eds.)

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces. (LSP)

  10. Encrypted integer division

    NARCIS (Netherlands)

    Veugen, P.J.M.

    2010-01-01

    When processing signals in the encrypted domain, homomorphic encryption can be used to enable linear operations on encrypted data. Integer division of encrypted data however requires an additional protocol with the server and will be relatively expensive. We present new solutions for dividing encryp

  11. The Problem with Division

    Science.gov (United States)

    Pope, Sue

    2012-01-01

    Of the "big four", division is likely to regarded by many learners as "the odd one out", "the difficult one", "the one that is complicated", or "the scary one". It seems to have been that way "for ever", in the perception of many who have trodden the learning pathways through the world of number. But, does it have to be like this? Clearly the…

  12. Pattern formation in Escherichia coli: A model for the pole-to-pole oscillations of Min proteins and the localization of the division site

    OpenAIRE

    2001-01-01

    Proper cell division requires an accurate definition of the division plane. In bacteria, this plane is determined by a polymeric ring of the FtsZ protein. The site of Z ring assembly in turn is controlled by the Min system, which suppresses FtsZ polymerization at noncentral membrane sites. The Min proteins in Escherichia coli undergo a highly dynamic localization cycle, during which they oscillate between the membrane of both cell halves. By using computer simulati...

  13. Atmospheric and Geophysical Sciences Division: Program report, FY 1987

    Energy Technology Data Exchange (ETDEWEB)

    1988-05-01

    In 1988 the Atmospheric and Geophysical Sciences Division began its 15th year as a division. As the Division has grown over the years, its modeling capabilities have expanded to include a broad range of time and space scales ranging from hours to years, and from kilometers to global, respectively. For this report, we have chosen to show a subset of results from several projects to illustrate the breadth, depth, and diversity of the modeling activities that are a major part of the Division's research, development, and application efforts. In addition, the recent reorganization of the Division, including the merger of another group with the Division, is described, and the budget, personnel, models, and publications are reviewed. 95 refs., 26 figs., 2 tabs.

  14. Podcast: The Electronic Crimes Division

    Science.gov (United States)

    Sept 26, 2016. Chris Lukas, the Special Agent in Charge of the Electronic Crimes Division within the OIG's Office of Investigations talks about computer forensics, cybercrime in the EPA and his division's role in criminal investigations.

  15. 2016 T Division Lightning Talks

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, Marilyn Leann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Adams, Luke Clyde [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Ferre, Gregoire Robing [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Grantcharov, Vesselin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Iaroshenko, Oleksandr [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Krishnapriyan, Aditi [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Kurtakoti, Prajvala Kishore [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Le Thien, Minh Quan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Lim, Jonathan Ng [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Low, Thaddeus Song En [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Lystrom, Levi Aaron [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Ma, Xiaoyu [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Nguyen, Hong T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Pogue, Sabine Silvia [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Orandle, Zoe Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Reisner, Andrew Ray [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Revard, Benjamin Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Roy, Julien [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Sandor, Csanad [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Slavkova, Kalina Polet [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Weichman, Kathleen Joy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Wu, Fei [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division; Yang, Yang [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division

    2016-11-29

    These are the slides for all of the 2016 T Division lightning talks. There are 350 pages worth of slides from different presentations, all of which cover different topics within the theoretical division at Los Alamos National Laboratory (LANL).

  16. 75 FR 16178 - Antitrust Division

    Science.gov (United States)

    2010-03-31

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Antitrust Division Notice Pursuant to the National Cooperative Research and Production Act of 1993--Joint... Director of Operations, Antitrust Division. BILLING CODE 4410-11-M...

  17. Biorepositories- | Division of Cancer Prevention

    Science.gov (United States)

    Carefully collected and controlled high-quality human biospecimens, annotated with clinical data and properly consented for investigational use, are available through the Division of Cancer Prevention Biorepositories listed in the charts below. Biorepositories Managed by the Division of Cancer Prevention Biorepositories Supported by the Division of Cancer Prevention Related Biorepositories | Information about accessing biospecimens collected from DCP-supported clinical trials and projects.

  18. CAS Academic Divisions in 2001

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ 1.Election of New Members In 2001, 56 scientists were elected new CAS members, including l0 in the Division of Mathematics & Physics, 10 in the Division of Chemistry, 12 in the Division of Biology, nine in the Division of Earth Sciences and 15 in the Division of Engineering Sciences.The average age of the new members is 60.4, and the youngest one is 38 years old. They are now working in nine provinces or municipalities, or governmental departments under the State Council, including 23 outstanding experts working for the CAS.

  19. Mice deleted for cell division cycle 73 gene develop parathyroid and uterine tumours: model for the hyperparathyroidism-jaw tumour syndrome.

    Science.gov (United States)

    Walls, G V; Stevenson, M; Lines, K E; Newey, P J; Reed, A A C; Bowl, M R; Jeyabalan, J; Harding, B; Bradley, K J; Manek, S; Chen, J; Wang, P; Williams, B O; Teh, B T; Thakker, R V

    2017-03-13

    The hyperparathyroidism-jaw tumour (HPT-JT) syndrome is an autosomal dominant disorder characterized by occurrence of parathyroid tumours, often atypical adenomas and carcinomas, ossifying jaw fibromas, renal tumours and uterine benign and malignant neoplasms. HPT-JT is caused by mutations of the cell division cycle 73 (CDC73) gene, located on chromosome 1q31.2 and encodes a 531 amino acid protein, parafibromin. To facilitate in vivo studies of Cdc73 in tumourigenesis we generated conventional (Cdc73(+/-)) and conditional parathyroid-specific (Cdc73(+/L)/PTH-Cre and Cdc73(L/L)/PTH-Cre) mouse models. Mice were aged to 18-21 months and studied for survival, tumour development and proliferation, and serum biochemistry, and compared to age-matched wild-type (Cdc73(+/+) and Cdc73(+/+)/PTH-Cre) littermates. Survival of Cdc73(+/-) mice, when compared to Cdc73(+/+) mice was reduced (Cdc73(+/-)=80%; Cdc73(+/+)=90% at 18 months of age, Pfourfold higher than that in parathyroid glands of wild-type littermates (P<0.0001). Cdc73(+/-), Cdc73(+/L)/PTH-Cre and Cdc73(L/L)/PTH-Cre mice had higher mean serum calcium concentrations than wild-type littermates, and Cdc73(+/-) mice also had increased mean serum parathyroid hormone (PTH) concentrations. Parathyroid tumour development, and elevations in serum calcium and PTH, were similar in males and females. Cdc73(+/-) mice did not develop bone or renal tumours but female Cdc73(+/-) mice, at 18 months of age, had uterine neoplasms comprising squamous metaplasia, adenofibroma and adenomyoma. Uterine neoplasms, myometria and jaw bones of Cdc73(+/-) mice had increased proliferation rates that were 2-fold higher than in Cdc73(+/+) mice (P<0.05). Thus, our studies, which have established mouse models for parathyroid tumours and uterine neoplasms that develop in the HPT-JT syndrome, provide in vivo models for future studies of these tumours.Oncogene advance online publication, 13 March 2017; doi:10.1038/onc.2017.43.

  20. Dynamical Localization of DivL and PleC in the Asymmetric Division Cycle of Caulobacter crescentus: A Theoretical Investigation of Alternative Models.

    Science.gov (United States)

    Subramanian, Kartik; Paul, Mark R; Tyson, John J

    2015-07-01

    Cell-fate asymmetry in the predivisional cell of Caulobacter crescentus requires that the regulatory protein DivL localizes to the new pole of the cell where it up-regulates CckA kinase, resulting in a gradient of CtrA~P across the cell. In the preceding stage of the cell cycle (the "stalked" cell), DivL is localized uniformly along the cell membrane and maintained in an inactive form by DivK~P. It is unclear how DivL overcomes inhibition by DivK~P in the predivisional cell simply by changing its location to the new pole. It has been suggested that co-localization of DivL with PleC phosphatase at the new pole is essential to DivL's activity there. However, there are contrasting views on whether the bifunctional enzyme, PleC, acts as a kinase or phosphatase at the new pole. To explore these ambiguities, we formulated a mathematical model of the spatiotemporal distributions of DivL, PleC and associated proteins (DivJ, DivK, CckA, and CtrA) during the asymmetric division cycle of a Caulobacter cell. By varying localization profiles of DivL and PleC in our model, we show how the physiologically observed spatial distributions of these proteins are essential for the transition from a stalked cell to a predivisional cell. Our simulations suggest that PleC is a kinase in predivisional cells, and that, by sequestering DivK~P, the kinase form of PleC enables DivL to be reactivated at the new pole. Hence, co-localization of PleC kinase and DivL is essential to establishing cellular asymmetry. Our simulations reproduce the experimentally observed spatial distribution and phosphorylation status of CtrA in wild-type and mutant cells. Based on the model, we explore novel combinations of mutant alleles, making predictions that can be tested experimentally.

  1. Dynamical Localization of DivL and PleC in the Asymmetric Division Cycle of Caulobacter crescentus: A Theoretical Investigation of Alternative Models.

    Directory of Open Access Journals (Sweden)

    Kartik Subramanian

    2015-07-01

    Full Text Available Cell-fate asymmetry in the predivisional cell of Caulobacter crescentus requires that the regulatory protein DivL localizes to the new pole of the cell where it up-regulates CckA kinase, resulting in a gradient of CtrA~P across the cell. In the preceding stage of the cell cycle (the "stalked" cell, DivL is localized uniformly along the cell membrane and maintained in an inactive form by DivK~P. It is unclear how DivL overcomes inhibition by DivK~P in the predivisional cell simply by changing its location to the new pole. It has been suggested that co-localization of DivL with PleC phosphatase at the new pole is essential to DivL's activity there. However, there are contrasting views on whether the bifunctional enzyme, PleC, acts as a kinase or phosphatase at the new pole. To explore these ambiguities, we formulated a mathematical model of the spatiotemporal distributions of DivL, PleC and associated proteins (DivJ, DivK, CckA, and CtrA during the asymmetric division cycle of a Caulobacter cell. By varying localization profiles of DivL and PleC in our model, we show how the physiologically observed spatial distributions of these proteins are essential for the transition from a stalked cell to a predivisional cell. Our simulations suggest that PleC is a kinase in predivisional cells, and that, by sequestering DivK~P, the kinase form of PleC enables DivL to be reactivated at the new pole. Hence, co-localization of PleC kinase and DivL is essential to establishing cellular asymmetry. Our simulations reproduce the experimentally observed spatial distribution and phosphorylation status of CtrA in wild-type and mutant cells. Based on the model, we explore novel combinations of mutant alleles, making predictions that can be tested experimentally.

  2. Energy Technology Division research summary -- 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    Research funded primarily by the NRC is directed toward assessing the roles of cyclic fatigue, intergranular stress corrosion cracking, and irradiation-assisted stress corrosion cracking on failures in light water reactor (LWR) piping systems, pressure vessels, and various core components. In support of the fast reactor program, the Division has responsibility for fuel-performance modeling and irradiation testing. The Division has major responsibilities in several design areas of the proposed International Thermonuclear Experimental Reactor (ITER). The Division supports the DOE in ensuring safe shipment of nuclear materials by providing extensive review of the Safety Analysis Reports for Packaging (SARPs). Finally, in the nuclear area they are investigating the safe disposal of spent fuel and waste. In work funded by DOE`s Energy Efficiency and Renewable Energy, the high-temperature superconductivity program continues to be a major focal point for industrial interactions. Coatings and lubricants developed in the division`s Tribology Section are intended for use in transportation systems of the future. Continuous fiber ceramic composites are being developed for high-performance heat engines. Nondestructive testing techniques are being developed to evaluate fiber distribution and to detect flaws. A wide variety of coatings for corrosion protection of metal alloys are being studied. These can increase lifetimes significant in a wide variety of coal combustion and gasification environments.

  3. Neuron division or enucleation.

    Science.gov (United States)

    Sotnikov, O S; Laktionova, A A; Solovieva, I A; Krasnova, T V

    2010-10-01

    The classical Bielschowsky-Gross neurohistological method was used to reproduce all the morphological phenomena interpreted by many authors as signs of neuron division, budding, and fission. It is suggested that these signs are associated with the effects of enucleation, which occurs in many cells of other tissue types in response to a variety of chemical and physical treatments. Studies were performed using neurons isolated from the mollusk Lymnaea stagnalis and exposed in tissue culture to the actin microfilament inhibitor cytochalasin B. Phase contrast time-lapse video recording over periods of 4-8 h demonstrated nuclear displacement, ectopization, and budding, to the level of almost complete fission of the neuron body. This repeats the pattern seen in static fixed preparations in "normal" conditions and after different experimental treatments. Budding of the cytoplasm was also sometimes seen at the early stages of the experiments. Control experiments in which cultured neurons were exposed to the solvent for cytochalasin B, i.e., dimethylsulfoxide (DMSO), did not reveal any changes in neurons over a period of 8 h. We take the view that the picture previously interpreted as neuron division and fission can be explained in terms of the inhibition of actin microfilaments, sometimes developing spontaneously in cells undergoing individual metabolic changes preventing the maintenance of cytoskeleton stability.

  4. Deconstructing Calculation Methods, Part 4: Division

    Science.gov (United States)

    Thompson, Ian

    2008-01-01

    In the final article of a series of four, the author deconstructs the primary national strategy's approach to written division. The approach to division is divided into five stages: (1) mental division using partition; (2) short division of TU / U; (3) "expanded" method for HTU / U; (4) short division of HTU / U; and (5) long division. [For part…

  5. Budget Setting Strategies for the Company's Divisions

    NARCIS (Netherlands)

    Berg, M.; Brekelmans, R.C.M.; De Waegenaere, A.M.B.

    1997-01-01

    The paper deals with the issue of budget setting to the divisions of a company. The approach is quantitative in nature both in the formulation of the requirements for the set-budgets, as related to different general managerial objectives of interest, and in the modelling of the inherent uncertaintie

  6. Hydraulic modeling and simulation of a System Division of Essential Service Water in a BWR plant with Flow master; Modelo hidraulico y simulacion de una division del Sistema de Agua de Servicio Esencial de una central BWR con Flowmaster

    Energy Technology Data Exchange (ETDEWEB)

    Vegazo Juzgado, L.; Rodriguez Garcia, G. M.; Mota Coloma, M.

    2012-07-01

    At the conclusion of the project can say that Flow master is a simulation tool that allows you to create your model from a library of components and obtain useful results from the point of view of the operation, engineering and maintenance. Compared to previous software from the point of view of use, can comment that Flow master is a tool which has an intuitive and user-friendly interaction between the user and the program thus facilitating the modeling of the system and definition of the components of same.

  7. Bipolarity and the relational division

    OpenAIRE

    Tamani, Nouredine; Lietard, Ludovic; Rocacher, Daniel

    2011-01-01

    International audience; A fuzzy bipolar relation is a relation defined by a fuzzy bipolar condition, which could be interpreted as an association of a constraint and a wish. In this context, the extension of the relational division operation to bipolarity is studied in this paper. Firstly, we define a bipolar division when the involved relations are crisp. Then, we define, from the semantic point of view, several forms of bipolar division when the involved relations are defined by fuzzy bipol...

  8. Situational Awareness and Logistics Division

    Data.gov (United States)

    Federal Laboratory Consortium — Volpe's Situational Awareness and Logistics Division researches, develops, implements, and analyzes advanced systems to protect, enhance, and ensure resilienceof the...

  9. Systems Safety and Engineering Division

    Data.gov (United States)

    Federal Laboratory Consortium — Volpe's Systems Safety and Engineering Division conducts engineering, research, and analysis to improve transportation safety, capacity, and resiliency. We provide...

  10. Security and Emergency Management Division

    Data.gov (United States)

    Federal Laboratory Consortium — Volpe's Security and Emergency Management Division identifies vulnerabilities, risks, and opportunities to improve the security of transportation systems, critical...

  11. Infrastructure Engineering and Deployment Division

    Data.gov (United States)

    Federal Laboratory Consortium — Volpe's Infrastructure Engineering and Deployment Division advances transportation innovation by being leaders in infrastructure technology, including vehicles and...

  12. Accelerator Technology Division

    Science.gov (United States)

    1992-04-01

    In fiscal year (FY) 1991, the Accelerator Technology (AT) division continued fulfilling its mission to pursue accelerator science and technology and to develop new accelerator concepts for application to research, defense, energy, industry, and other areas of national interest. This report discusses the following programs: The Ground Test Accelerator Program; APLE Free-Electron Laser Program; Accelerator Transmutation of Waste; JAERI, OMEGA Project, and Intense Neutron Source for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Super Collider; The High-Power Microwave Program; (Phi) Factory Collaboration; Neutral Particle Beam Power System Highlights; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  13. Deconstructing Interocular Suppression: Attention and Divisive Normalization.

    Directory of Open Access Journals (Sweden)

    Hsin-Hung Li

    2015-10-01

    Full Text Available In interocular suppression, a suprathreshold monocular target can be rendered invisible by a salient competitor stimulus presented in the other eye. Despite decades of research on interocular suppression and related phenomena (e.g., binocular rivalry, flash suppression, continuous flash suppression, the neural processing underlying interocular suppression is still unknown. We developed and tested a computational model of interocular suppression. The model included two processes that contributed to the strength of interocular suppression: divisive normalization and attentional modulation. According to the model, the salient competitor induced a stimulus-driven attentional modulation selective for the location and orientation of the competitor, thereby increasing the gain of neural responses to the competitor and reducing the gain of neural responses to the target. Additional suppression was induced by divisive normalization in the model, similar to other forms of visual masking. To test the model, we conducted psychophysics experiments in which both the size and the eye-of-origin of the competitor were manipulated. For small and medium competitors, behavioral performance was consonant with a change in the response gain of neurons that responded to the target. But large competitors induced a contrast-gain change, even when the competitor was split between the two eyes. The model correctly predicted these results and outperformed an alternative model in which the attentional modulation was eye specific. We conclude that both stimulus-driven attention (selective for location and feature and divisive normalization contribute to interocular suppression.

  14. Genes involved in cell division in mycoplasmas

    Directory of Open Access Journals (Sweden)

    Frank Alarcón

    2007-01-01

    Full Text Available Bacterial cell division has been studied mainly in model systems such as Escherichia coli and Bacillus subtilis, where it is described as a complex process with the participation of a group of proteins which assemble into a multiprotein complex called the septal ring. Mycoplasmas are cell wall-less bacteria presenting a reduced genome. Thus, it was important to compare their genomes to analyze putative genes involved in cell division processes. The division and cell wall (dcw cluster, which in E. coli and B. subtilis is composed of 16 and 17 genes, respectively, is represented by only three to four genes in mycoplasmas. Even the most conserved protein, FtsZ, is not present in all mycoplasma genomes analyzed so far. A model for the FtsZ protein from Mycoplasma hyopneumoniae and Mycoplasma synoviae has been constructed. The conserved residues, essential for GTP/GDP binding, are present in FtsZ from both species. A strong conservation of hydrophobic amino acid patterns is observed, and is probably necessary for the structural stability of the protein when active. M. synoviae FtsZ presents an extended amino acid sequence at the C-terminal portion of the protein, which may participate in interactions with other still unknown proteins crucial for the cell division process.

  15. Developmental control of cell division

    NARCIS (Netherlands)

    Boxem, M. (Mike)

    2002-01-01

    During development of multicellular organisms, cell divisions need to be coordinated with the developmental program of the entire organism. Although the mechanisms that drive cells through the division cycle are well understood, very little is known about the pathways that link extracellular signals

  16. Lightning Talks 2015: Theoretical Division

    Energy Technology Data Exchange (ETDEWEB)

    Shlachter, Jack S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-25

    This document is a compilation of slides from a number of student presentations given to LANL Theoretical Division members. The subjects cover the range of activities of the Division, including plasma physics, environmental issues, materials research, bacterial resistance to antibiotics, and computational methods.

  17. Developmental control of cell division

    NARCIS (Netherlands)

    Boxem, M. (Mike)

    2002-01-01

    During development of multicellular organisms, cell divisions need to be coordinated with the developmental program of the entire organism. Although the mechanisms that drive cells through the division cycle are well understood, very little is known about the pathways that link extracellular signals

  18. Division of Analytical Chemistry, 1998

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    1999-01-01

    The article recounts the 1998 activities of the Division of Analytical Chemistry (DAC- formerly the Working Party on Analytical Chemistry, WPAC), which body is a division of the Federation of European Chemical Societies (FECS). Elo Harald Hansen is the Danish delegate, representing The Danish...... Chemical Society/The Society for Analytical Chemistry....

  19. 78 FR 17431 - Antitrust Division

    Science.gov (United States)

    2013-03-21

    ... January 2, 2013 (78 FR 117). Patricia A. Brink, Director of Civil Enforcement, Antitrust Division. BILLING...) of the Act on July 30, 2001 (66 FR 39336). The last notification was filed with the Department on... Antitrust Division Notice Pursuant to the National Cooperative Research and Production Act of...

  20. 77 FR 54611 - Antitrust Division

    Science.gov (United States)

    2012-09-05

    ... on June 8, 2012 (77 FR 34067). Patricia A. Brink, Director of Civil Enforcement, Antitrust Division... Section 6(b) of the Act on June 30, 2000 (65 FR 40693). The last notification was filed with the... Antitrust Division Notice Pursuant to the National Cooperative Research and Production Act of...

  1. Physics division annual report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Glover, J.; Physics

    2007-03-12

    This report highlights the research performed in 2005 in the Physics Division of Argonne National Laboratory. The Division's programs include operation of ATLAS as a national user facility, nuclear structure and reaction research, nuclear theory, medium energy nuclear research and accelerator research and development. The mission of Nuclear Physics is to understand the origin, evolution and structure of baryonic matter in the universe--the matter that makes up stars, planets and human life itself. The Division's research focuses on innovative new ways to address this mission and 2005 was a year of great progress. One of the most exciting developments is the initiation of the Californium Rare Ion Breeder Upgrade, CARIBU. By combining a Cf-252 fission source, the gas catcher technology developed for rare isotope beams, a high-resolution isobar separator, and charge breeding ECR technology, CARIBU will make hundreds of new neutron-rich isotope beams available for research. The cover illustration shows the anticipated intensities of low-energy beams that become available for low-energy experiments and for injection into ATLAS for reacceleration. CARIBU will be completed in early 2009 and provide us with considerable experience in many of the technologies developed for a future high intensity exotic beam facility. Notable results in research at ATLAS include a measurement of the isomeric states in {sup 252}No that helps pin down the single particle structure expected for superheavy elements, and a new low-background measurement of {sup 16}N beta-decay to determine the {sup 12}C({alpha},{gamma}){sup 16}O reaction rate that is so important in astrophysical environments. Precise mass measurements shed new light on the unitarity of the quark weak-mixing matrix in the search for physics beyond the standard model. ATLAS operated for 4686 hours of research in FY2005 while achieving 95% efficiency of beam delivery for experiments. In Medium-Energy Physics, radium

  2. Physics Division computer facilities

    Energy Technology Data Exchange (ETDEWEB)

    Cyborski, D.R.; Teh, K.M.

    1995-08-01

    The Physics Division maintains several computer systems for data analysis, general-purpose computing, and word processing. While the VMS VAX clusters are still used, this past year saw a greater shift to the Unix Cluster with the addition of more RISC-based Unix workstations. The main Divisional VAX cluster which consists of two VAX 3300s configured as a dual-host system serves as boot nodes and disk servers to seven other satellite nodes consisting of two VAXstation 3200s, three VAXstation 3100 machines, a VAX-11/750, and a MicroVAX II. There are three 6250/1600 bpi 9-track tape drives, six 8-mm tapes and about 9.1 GB of disk storage served to the cluster by the various satellites. Also, two of the satellites (the MicroVAX and VAX-11/750) have DAPHNE front-end interfaces for data acquisition. Since the tape drives are accessible cluster-wide via a software package, they are, in addition to replay, used for tape-to-tape copies. There is however, a satellite node outfitted with two 8 mm drives available for this purpose. Although not part of the main cluster, a DEC 3000 Alpha machine obtained for data acquisition is also available for data replay. In one case, users reported a performance increase by a factor of 10 when using this machine.

  3. Earth Sciences Division annual report 1990

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-06-01

    This Annual Report presents summaries of selected representative research activities grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrogeology, Geology and Geochemistry, and Geophysics and Geomechanics. Much of the Division`s research deals with the physical and chemical properties and processes in the earth`s crust, from the partially saturated, low-temperature near-surface environment to the high-temperature environments characteristic of regions where magmatic-hydrothermal processes are active. Strengths in laboratory and field instrumentation, numerical modeling, and in situ measurement allow study of the transport of mass and heat through geologic media -- studies that now include the appropriate chemical reactions and the hydraulic-mechanical complexities of fractured rock systems. Of particular note are three major Division efforts addressing problems in the discovery and recovery of petroleum, the application of isotope geochemistry to the study of geodynamic processes and earth history, and the development of borehole methods for high-resolution imaging of the subsurface using seismic and electromagnetic waves. In 1989 a major DOE-wide effort was launched in the areas of Environmental Restoration and Waste Management. Many of the methods previously developed for and applied to deeper regions of the earth will in the coming years be turned toward process definition and characterization of the very shallow subsurface, where man-induced contaminants now intrude and where remedial action is required.

  4. PENERAPAN MODEL PEMBELAJARAN KOOPERATIF TIPE STUDENT TEAM ACHIEVMENT DIVISION (STAD UNTUK MENINGKATKAN AKTIVITAS DAN HASIL BELAJAR PADA KOMPETENSI DASAR MEMELIHARA PERALATAN KANTOR SISWA KELAS X.3 AP SMK KRISTEN SALATIGA

    Directory of Open Access Journals (Sweden)

    Septian Dwi Prasetyo

    2013-01-01

    Full Text Available Tujuannya adalah untuk mengetahui apakah penerapan model pembelajaran kooperatif tipe Student Team Achievment Division (STAD dapat meningkatkan aktivitas dan hasil belajar memelihara peralatan kantor sisiwa kelas X.3 AP SMK Kristen Salatiga. Penelitian ini menggunakan desain PTK. Subjek penelitiannya adalah siswa kelas X.3 AP SMK Kristen Salatiga. Penelitian ini terdiri dari 2 siklus, tiap siklus terdiri dari perencanaan, tindakan, observasi, dan refleksi. Data diperoleh dengan instrumen tes berupa soal pilihan ganda, dan instrumen nontes berupa lembar observasi. Analisis data dilakukan dengan teknik analisis deskriptif persentase. Hasil analisis data penelitian dari prasiklus, siklus I dan II mengalami peningkatan hasil belajar secara klasikal 46,88%, 62,50%, dan 90,63%, jadi ada kenaikan 15,62 % pada siklus I dan 28,13% pada siklus II. Sedangkan untuk rata-rata aktivitas siswa 63,63% pada siklus I dan 81,13% pada siklus II. Berdasarkan hasil penelitian di atas dapat disimpulkan bahwa penerapan model pembelajaran kooperatif tipe Student Team Achievment Division (STAD dapat meningkatkan aktivitas dan hasil belajar memelihara peralatan kantor siswa kelas X.3 AP SMK Kristen Salatiga, dengan keterlibatan siswa secara aktif selama proses pembelajaran berlangsung. The goal is to determine whether the application of Student Team Achievment Division (STAD cooperative learning model to improve the activity and learning outcomes maintain office equipment AP class X.3 students of SMK Christian Salatiga. The design of this study PTK. Research subject is a class X.3 student of SMK Christian AP Salatiga. The study consisted of two cycles, each cycle consisting of planning, action, observation, and reflection. Date obtained with the test instrument in the form of multiple choice questions, and a nontest instruments observation sheet. Date were analyzed by descriptive analysis techniques percentage. The results of the analysis of research data prasiklus, Cycle

  5. Cellular Clocks : Coupled Circadian Dispatch and Cell Division Cycles

    NARCIS (Netherlands)

    Merrow, Martha; Roenneberg, Till

    2004-01-01

    Gating of cell division by the circadian clock is well known, yet its mechanism is little understood. Genetically tractable model systems have led to new hypotheses and questions concerning the coupling of these two cellular cycles.

  6. Cellular Clocks : Coupled Circadian Dispatch and Cell Division Cycles

    NARCIS (Netherlands)

    Merrow, Martha; Roenneberg, Till

    2004-01-01

    Gating of cell division by the circadian clock is well known, yet its mechanism is little understood. Genetically tractable model systems have led to new hypotheses and questions concerning the coupling of these two cellular cycles.

  7. Physics division annual report 2006.

    Energy Technology Data Exchange (ETDEWEB)

    Glover, J.; Physics

    2008-02-28

    This report highlights the activities of the Physics Division of Argonne National Laboratory in 2006. The Division's programs include the operation as a national user facility of ATLAS, the Argonne Tandem Linear Accelerator System, research in nuclear structure and reactions, nuclear astrophysics, nuclear theory, investigations in medium-energy nuclear physics as well as research and development in accelerator technology. The mission of nuclear physics is to understand the origin, evolution and structure of baryonic matter in the universe--the core of matter, the fuel of stars, and the basic constituent of life itself. The Division's research focuses on innovative new ways to address this mission.

  8. ftsZ gene and plastid division

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Plastid is one of the most important cellular organelles, the normal division process of plastid is essential for the differentiation and development of plant cells. For a long time, morphological observations and genetic analyses to special mutants are the major research fields of plastid division, but the molecular mechanisms underlying plastid division are largely unknown. Because of the endosymbiotic origin, plastid division might have mechanisms in common with those involved in bacterial cell division. It has been proved that several prokaryotic cell division genes also participate in the plastid division. Recently, the mechanisms of prokaryotic cell division have been well documented, which provides a valuable paradigm for understanding the plastid division mechanisms. In plants, the functional analyses of ftsZ, a key gene involved both in bacteria and plastid division, have established the solid foundation for people to understand the plastid division in molecular level. In this paper we will make a review for the research history and progress of plastid division.

  9. Analysis and Simulation for Capacity of Time Division-Synchronous Code Division Multiple Access System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Capacity both in uplink and downlink of TD-SCDMA (time division-synchronous code division multiple access)system is studied in a multi-cell environment. The theoretical expressions of the mean of intercell interference in uplinkand the mean of sum of power allocation in downlink are given, by which uplink and downlink capacity is analyzed.Furthermore, we give the simulation models for both uplink and downlink capacity. The results from theoretical analysisand simulation fit very well. In the end, the maximum number of users that TD-SCDMA system can serve for 12.2kspeech service is given.

  10. [Division of regulatory cellular systems (Lvov)].

    Science.gov (United States)

    Kusen', S I

    1995-01-01

    Two departments of the A. V. Palladin Institute of Biochemistry of the National Academy of Sciences of Ukraine were founded in 1969 in Lviv. These were: the Department of Biochemistry of Cell Differentiation headed by Professor S. I. Kusen and Department of Regulation of Cellular Synthesis of Low Molecular Weight Compounds headed by Professor G. M. Shavlovsky. The Lviv Division of the A. V. Palladin Institute of Biochemistry of the National Academy of Sciences of Ukraine with Professor S. I. Kusen as its chief, was founded in 1974 on the basis of these departments and the Laboratory of Modelling of Regulatory Cellular Systems headed by Professor M. P. Derkach. The above mentioned laboratory which was not the structural unit obtained the status of Structural Laboratory of Cellular Biophysics in 1982 and was headed by O. A. Goida, Candidate of biological sciences. From 1983 the Laboratory of Correcting Therapy of Malignant Tumors and Hemoblastoses at the Institute of Molecular Biology and Genetics, Academy of Sciences of Ukraine (Chief--S. V. Ivasivka, Candidate of medical sciences) was included in the structure of the Division. That Laboratory was soon transformed into the Department of Carbohydrate Metabolism Regulation headed by Professor I. D. Holovatsky. In 1988 this Department was renamed into the Department of Glycoprotein Biochemistry and headed by M. D. Lutsik, Doctor of biological sciences. In 1982 one more Laboratory of Biochemical Genetics was founded at the Department of Regulation of Cellular Synthesis of Low Molecular Weight Compounds, in 1988 it was transformed into the Department of Biochemical Genetics (Chief--Professor A. A. Sibirny). In 1989 the Laboratory of Anion Transport was taken from A. V. Palladin Institute of Biochemistry, Academy of Sciences of Ukraine to Lviv Division of this Institute. This laboratory was headed by Professor M. M. Veliky. One more reorganization in the Division structure took place in 1994. The Department of

  11. Division 1137 property control system

    Energy Technology Data Exchange (ETDEWEB)

    Pastor, D.J.

    1982-01-01

    An automated data processing property control system was developed by Mobile and Remote Range Division 1137. This report describes the operation of the system and examines ways of using it in operational planning and control.

  12. High division of sciatic nerve

    Directory of Open Access Journals (Sweden)

    Tripti Shrivastava

    2014-04-01

    Results: In all except two cadavers, the nerve divided at the apex of the popliteal fossa. In two cadavers the sciatic nerve divided bilaterally in the upper part of thigh. Conclusion: The high division presented in this study can make popliteal nerve blocks partially ineffective. The high division of sciatic nerve must always be borne in mind as they have important clinical implications. [Int J Res Med Sci 2014; 2(2.000: 686-688

  13. Applied Physics Division 1998 Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Cecchini, M.; Crescentini, L; Ghezzi, L.; Kent, C.; Bottomei, M. [ENEA, Centro Ricerche Frascati, Frascati, RM (Italy). Applied physics Division

    1999-07-01

    This report outlines the 1998 research activities carried out by the Applied Physics Division of the Innovation Department of ENEA (Italian Agency for New Technologies, Energy and Environment). The fields addressed and discussed include: optical and electro-optical technologies (chaps. 1 and 2); accelerator technologies (chap. 3); diagnostic systems for science and engineering (chaps. 4 and 5); theory, modelling and computational methods (chaps. 6 and 7). The aim of the Applied Physics Division is to develop technologies and systems that can be directly applied by internal (ENEA) and external users in research (high-resolution spectroscopy, laser-generated soft-x-ray sources), production processes (laser material photoproduction, structural analysis), social, cultural and environmental sciences (laser remote sensing, modelling of ecosystems and population dynamics) and medicine (particle accelerator for radiotherapy). Most of the work in 1998 was performed by the division's laboratories at the Frascati, Casaccia and Bologna Research Centres of ENEA; some was done elsewhere in collaboration with other ENEA units, external laboratories and industries. A good share of the activities was carried out for international projects; in particular, the IV European Union Framework Program.

  14. Theoretical Model of International Labor Division and Structural Changes under General Equilibrium%国际分工与产业结构变动的一般均衡理论模型

    Institute of Scientific and Technical Information of China (English)

    张捷; 林新孟

    2012-01-01

    本文在全面均衡的框架下,融合了H-O模型和古典经济增长模型的思想,建立了分析国际分工与产业结构变动关系的理论模型。模型将封闭经济条件下产业结构变动的诱因分解为三个因素:消费因素、资本因素和劳动力因素,探讨了这三个因素对产业结构变动的影响机制和产业结构的变化轨迹;然后进一步分析了开放经济条件下产业结构向后工业化过渡的内外影响因素;最后,初步检验了基于制造一服务的国际分工模式对我国由工业经济向服务经济升级转型的不利影响。%Under the framework of general equilibrium, this paper establishes a theoretical model of international labor division and industrial structural changes , using Heckscher- Ohlin model and classical growth model. Firstly, the model resolves the structural changes in a closed economy into 3 motivators: con- sumption factor, capital factor and labor factor. Then, the model analyzes the inner and outer factors of structural changes in an open economy. Furthermore, we study the negative impacts on Chinese process of post - industrialization from the pattern of international manufacturing - service labor division.

  15. Kinetics of cell division in epidermal maintenance

    CERN Document Server

    Klein, Allon M; Jones, Philip H; Simons, Benjamin D

    2007-01-01

    The rules governing cell division and differentiation are central to understanding the mechanisms of development, aging and cancer. By utilising inducible genetic labelling, recent studies have shown that the clonal population in transgenic mouse epidermis can be tracked in vivo. Drawing on these results, we explain how clonal fate data may be used to infer the rules of cell division and differentiation underlying the maintenance of adult murine tail-skin. We show that the rates of cell division and differentiation may be evaluated by considering the long-time and short-time clone fate data, and that the data is consistent with cells dividing independently rather than synchronously. Motivated by these findings, we consider a mechanism for cancer onset based closely on the model for normal adult skin. By analysing the expected changes to clonal fate in cancer emerging from a simple two-stage mutation, we propose that clonal fate data may provide a novel method for studying the earliest stages of the disease.

  16. Pilotless Aircraft Research Division

    Science.gov (United States)

    1950-01-01

    Sperry Model 10 Velocimeter, Doppler radar at Wallops Island with trackers P.R. Mears and J. Quillen. Metallic ears pointed to the heavens, this radio tracking device kept tabs on Wallops rocket firings. Joseph Shortal has described this Doppler radar as follows: 'The Doppler radar was a genuine asset to PARD; it made possible the direct determination of velocity and allowed the measurement of drag for such simple models as the RM-2 and RM-5 types. Doppler radars were used in every launching from Wallops.' 'In cooperation with the Army's Aberdeen Proving Ground, specifications for a more powerful Doppler radar were prepared. A 150-watt radar which its manufacturer, Sperry Gyroscope Corp., called the Model 10 Velocimeter, was purchased. This radar was mounted on a SCR-547 trailer, which led Langley men to call it the TPS-547 radar for some time. This radar had a range of approximately five miles and was the first of a series of this type in use at Wallops for many years.' 'One operator directed the dishes toward the target in azimuth while the other operator controlled the elevation (The fact that two operators with independent gun sights and earphones could coordinate their efforts in this fashion surprised many 'experts'.). The Doppler radars were always located near the launcher and the operators normally served in the dual capacity of rocket technicians. After the Velocimeter was placed in operation, the TPS-5 radars were no longer used.' Photograph published in Winds of Change, a 75th Anniversary NASA publication (page 74), by James Schultz. Published in Joseph A. Shortal, History of Wallops Station: Origins and Activities Through 1949, (Wallops Island, VA: National Aeronautics and Space Administration, Wallops Station, nd), Comment Edition. Photograph published in A New Dimension; Wallops Island Flight Test Range: The First Fifteen Years by Joseph Adams Shortal. A NASA publication (page 99).

  17. On robustness of phase resetting to cell division under entrainment.

    Science.gov (United States)

    Ahmed, Hafiz; Ushirobira, Rosane; Efimov, Denis

    2015-12-21

    The problem of phase synchronization for a population of genetic oscillators (circadian clocks, synthetic oscillators, etc.) is considered in this paper, taking into account a cell division process and a common entrainment input in the population. The proposed analysis approach is based on the Phase Response Curve (PRC) model of an oscillator (the first order reduced model obtained for the linearized system and inputs with infinitesimal amplitude). The occurrence of cell division introduces state resetting in the model, placing it in the class of hybrid systems. It is shown that without common entraining input in all oscillators, the cell division acts as a disturbance causing phase drift, while the presence of entrainment guarantees boundedness of synchronization phase errors in the population. The performance of the obtained solutions is demonstrated via computer experiments for two different models of circadian/genetic oscillators (Neurospora׳s circadian oscillation model and the repressilator).

  18. Cell-Division Behavior in a Heterogeneous Swarm Environment.

    Science.gov (United States)

    Erskine, Adam; Herrmann, J Michael

    2015-01-01

    We present a system of virtual particles that interact using simple kinetic rules. It is known that heterogeneous mixtures of particles can produce particularly interesting behaviors. Here we present a two-species three-dimensional swarm in which a behavior emerges that resembles cell division. We show that the dividing behavior exists across a narrow but finite band of parameters and for a wide range of population sizes. When executed in a two-dimensional environment the swarm's characteristics and dynamism manifest differently. In further experiments we show that repeated divisions can occur if the system is extended by a biased equilibrium process to control the split of populations. We propose that this repeated division behavior provides a simple model for cell-division mechanisms and is of interest for the formation of morphological structure and to swarm robotics.

  19. Home | Division of Cancer Prevention

    Science.gov (United States)

    Our Research The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into cancer. |

  20. Environmental Transport Division: 1979 report

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, C.E. Jr.; Schubert, J.F.; Bowman, W.W.; Adams, S.E.

    1980-03-01

    During 1979, the Environmental Transport Division (ETD) of the Savannah River Laboratory conducted atmospheric, terrestrial, aquatic, and marine studies, which are described in a series of articles. Separate abstracts were prepared for each. Publications written about the 1979 research are listed at the end of the report.

  1. 78 FR 17430 - Antitrust Division

    Science.gov (United States)

    2013-03-21

    ... pursuant to Section 6(b) of the Act on April 4, 2003 (68 FR 16552). The last notification was filed with... Section 6(b) of the Act on March 23, 2012 (77 FR 17095). Patricia A. Brink, Director of Civil Enforcement... Antitrust Division Notice Pursuant to the National Cooperative Research and Production Act of...

  2. Operational Characterization of Divisibility of Dynamical Maps

    Science.gov (United States)

    Bae, Joonwoo; Chruściński, Dariusz

    2016-07-01

    In this work, we show the operational characterization to the divisibility of dynamical maps in terms of the distinguishability of quantum channels. It is proven that the distinguishability of any pair of quantum channels does not increase under divisible maps, in which the full hierarchy of divisibility is isomorphic to the structure of entanglement between system and environment. This shows that (i) channel distinguishability is the operational quantity signifying (detecting) divisibility (indivisibility) of dynamical maps and (ii) the decision problem for the divisibility of maps is as hard as the separability problem in entanglement theory. We also provide the information-theoretic characterization to the divisibility of maps with conditional min-entropy.

  3. Epithelial cell division in the Xenopus laevis embryo during gastrulation.

    Science.gov (United States)

    Hatte, Guillaume; Tramier, Marc; Prigent, Claude; Tassan, Jean-Pierre

    2014-01-01

    How vertebrate epithelial cells divide in vivo and how the cellular environment influences cell division is currently poorly understood. A sine qua non condition to study cell division in situ is the ease of observation of cell division. This is fulfilled in the Xenopus embryo at the gastrula stage where polarized epithelial cells divide with a high frequency at the surface of the organism. Recently, using this model system, we have shown that epithelial cells divide by asymmetric furrowing and that the mode of cell division is regulated during development. Here, we further characterize epithelial cell division in situ. To this end, we used confocal microscopy to study epithelial cell division in the ectoderm of the Xenopus laevis gastrula. Cell division was followed either by indirect immunofluorescence in fixed embryos or by live imaging of embryos transiently expressing diverse fluorescent proteins. Here, we show that during cytokinesis, the plasma membranes of the two daughter cells are usually separated by a gap. For most divisions, daughter cells make contacts basally at a distance from the furrow tip which creates an inverted teardrop-like shaped volume tightly associated with the furrow. At the end of cytokinesis, the inverted teardrop is resorbed; thus it is a transient structure. Several proteins involved in cytokinesis are localized at the tip of the inverted teardrop suggesting that the formation of the gap could be an active process. We also show that intercalation of neighboring cells between daughter cells occasionally occurs during cytokinesis. Our results reveal an additional level of complexity in the relationship between dividing cells and also with their neighboring cells during cytokinesis in the Xenopus embryo epithelium.

  4. Characterization of dependencies between growth and division in budding yeast.

    Science.gov (United States)

    Mayhew, Michael B; Iversen, Edwin S; Hartemink, Alexander J

    2017-02-01

    Cell growth and division are processes vital to the proliferation and development of life. Coordination between these two processes has been recognized for decades in a variety of organisms. In the budding yeast Saccharomyces cerevisiae, this coordination or 'size control' appears as an inverse correlation between cell size and the rate of cell-cycle progression, routinely observed in G1 prior to cell division commitment. Beyond this point, cells are presumed to complete S/G2/M at similar rates and in a size-independent manner. As such, studies of dependence between growth and division have focused on G1 Moreover, in unicellular organisms, coordination between growth and division has commonly been analysed within the cycle of a single cell without accounting for correlations in growth and division characteristics between cycles of related cells. In a comprehensive analysis of three published time-lapse microscopy datasets, we analyse both intra- and inter-cycle dependencies between growth and division, revisiting assumptions about the coordination between these two processes. Interestingly, we find evidence (i) that S/G2/M durations are systematically longer in daughters than in mothers, (ii) of dependencies between S/G2/M and size at budding that echo the classical G1 dependencies, and (iii) in contrast with recent bacterial studies, of negative dependencies between size at birth and size accumulated during the cell cycle. In addition, we develop a novel hierarchical model to uncover inter-cycle dependencies, and we find evidence for such dependencies in cells growing in sugar-poor environments. Our analysis highlights the need for experimentalists and modellers to account for new sources of cell-to-cell variation in growth and division, and our model provides a formal statistical framework for the continued study of dependencies between biological processes.

  5. Division of shape-standardized tobacco cells reveals a limit to the occurrence of single-criterion-based selection of the plane of symmetric division.

    Science.gov (United States)

    Asada, Tetsuhiro

    2013-06-01

    The plane of symmetric plant cell division tends to be selected so that the new cross-wall halving the cell volume has the least possible area, and several cases of such selection are best represented by a recently formulated model which promotes the view that the strength of the least area tendency is the only criterion for selecting the plane. To test this model, the present study examined the divisions of two types of shape-standardized tobacco BY-2 cell, oblate-spheroidal (os) cells prepared from protoplasts and spheri-cylindrical (sc) cells with unusual double-wall structures prepared from plasmolyzed cells. Measurements of cell shape parameters and division angles revealed that both cell types most frequently divide nearly along their short axes. While os cells did not exhibit any other division angle bias, sc cell division was characterized by another bias which made the frequency of longitudinal divisions secondarily high. The geometry of sc cells barely allows the longitudinal cross-walls to have locally minimum areas. Nevertheless, a comparison of detected and hypothetical standard divisions indicates that the frequency of longitudinal sc cell division can be significantly higher than that predicted when the longitudinal cross-walls are assumed to have locally minimum areas smaller than their original areas. These results suggest that, even in isolated plant cell types, the strength of the least area tendency is not the only criterion for selecting the division plane. The possibility that there is another basic, though often hidden, criterion is discussed.

  6. Defect driven shapes in nematic droplets: analogies with cell division

    CERN Document Server

    Leoni, Marco; Bowick, Mark J; Marchetti, M Cristina

    2016-01-01

    Building on the striking similarity between the structure of the spindle during mitosis in living cells and nematic textures in confined liquid crystals, we use a continuum model of two-dimensional nematic liquid crystal droplets, to examine the physical aspects of cell division. The model investigates the interplay between bulk elasticity of the microtubule assembly, described as a nematic liquid crystal, and surface elasticity of the cell cortex, modelled as a bounding flexible membrane, in controlling cell shape and division. The centrosomes at the spindle poles correspond to the cores of the topological defects required to accommodate nematic order in a closed geometry. We map out the progression of both healthy bipolar and faulty multi-polar division as a function of an effective parameter that incorporates active processes and controls centrosome separation. A robust prediction, independent of energetic considerations, is that the transition from a single cell to daughters cells occurs at critical value...

  7. Physiographic divisions of the conterminous U. S.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This is a polygon coverage of Physiographic Divisions in the conterminous United States. It was automated from Fenneman's 1:7,000,000-scale map, "Physical Divisions...

  8. Health, Safety, and Environment Division

    Energy Technology Data Exchange (ETDEWEB)

    Wade, C [comp.

    1992-01-01

    The primary responsibility of the Health, Safety, and Environmental (HSE) Division at the Los Alamos National Laboratory is to provide comprehensive occupational health and safety programs, waste processing, and environmental protection. These activities are designed to protect the worker, the public, and the environment. Meeting these responsibilities requires expertise in many disciplines, including radiation protection, industrial hygiene, safety, occupational medicine, environmental science and engineering, analytical chemistry, epidemiology, and waste management. New and challenging health, safety, and environmental problems occasionally arise from the diverse research and development work of the Laboratory, and research programs in HSE Division often stem from these applied needs. These programs continue but are also extended, as needed, to study specific problems for the Department of Energy. The results of these programs help develop better practices in occupational health and safety, radiation protection, and environmental science.

  9. Cell division in apicomplexan parasites.

    Science.gov (United States)

    Francia, Maria E; Striepen, Boris

    2014-02-01

    Toxoplasma gondii and Plasmodium falciparum are important human pathogens. These parasites and many of their apicomplexan relatives undergo a complex developmental process in the cells of their hosts, which includes genome replication, cell division and the assembly of new invasive stages. Apicomplexan cell cycle progression is both globally and locally regulated. Global regulation is carried out throughout the cytoplasm by diffusible factors that include cell cycle-specific kinases, cyclins and transcription factors. Local regulation acts on individual nuclei and daughter cells that are developing inside the mother cell. We propose that the centrosome is a master regulator that physically tethers cellular components and that provides spatial and temporal control of apicomplexan cell division.

  10. A mechanistic stochastic framework for regulating bacterial cell division.

    Science.gov (United States)

    Ghusinga, Khem Raj; Vargas-Garcia, Cesar A; Singh, Abhyudai

    2016-07-26

    How exponentially growing cells maintain size homeostasis is an important fundamental problem. Recent single-cell studies in prokaryotes have uncovered the adder principle, where cells add a fixed size (volume) from birth to division, irrespective of their size at birth. To mechanistically explain the adder principle, we consider a timekeeper protein that begins to get stochastically expressed after cell birth at a rate proportional to the volume. Cell-division time is formulated as the first-passage time for protein copy numbers to hit a fixed threshold. Consistent with data, the model predicts that the noise in division timing increases with size at birth. Intriguingly, our results show that the distribution of the volume added between successive cell-division events is independent of the newborn cell size. This was dramatically seen in experimental studies, where histograms of the added volume corresponding to different newborn sizes collapsed on top of each other. The model provides further insights consistent with experimental observations: the distribution of the added volume when scaled by its mean becomes invariant of the growth rate. In summary, our simple yet elegant model explains key experimental findings and suggests a mechanism for regulating both the mean and fluctuations in cell-division timing for controlling size.

  11. Prokaryotic cell division: flexible and diverse

    NARCIS (Netherlands)

    den Blaauwen, T.

    2013-01-01

    Gram-negative rod-shaped bacteria have different approaches to position the cell division initiating Z-ring at the correct moment in their cell division cycle. The subsequent maturation into a functional division machine occurs in vastly different species in two steps with appreciable time in

  12. Algebraic divisibility sequences over function fields

    CERN Document Server

    Ingram, Patrick; Silverman, Joseph H; Stange, Katherine E; Streng, Marco

    2011-01-01

    We study the existence of primes and of primitive divisors in classical divisibility sequences defined over function fields. Under various hypotheses, we prove that Lucas sequences and elliptic divisibility sequences over function fields defined over number fields contain infinitely many irreducible elements. We also prove that an elliptic divisibility sequence over a function field has only finitely many terms lacking a primitive divisor.

  13. Take a Bite out of Fraction Division

    Science.gov (United States)

    Cengiz, Nesrin; Rathouz, Margaret

    2011-01-01

    Division of fractions is often considered the most mechanical and least understood topic in elementary school. Enacting fraction division tasks in meaningful ways requires that teachers know not only "how" fraction division works but also "why" it works. The authors have created materials to help preservice teachers develop that knowledge. To…

  14. 77 FR 40586 - Coastal Programs Division

    Science.gov (United States)

    2012-07-10

    ... request for comments in the Federal Register at 77 FR 12245 on the request of Lockheed Martin Corp. to... National Oceanic and Atmospheric Administration Coastal Programs Division AGENCY: Coastal Programs Division... licenses. FOR FURTHER INFORMATION CONTACT: Kerry Kehoe, Coastal Programs Division (NORM/3), Office of...

  15. 7 CFR 29.16 - Division.

    Science.gov (United States)

    2010-01-01

    ... INSPECTION Regulations Definitions § 29.16 Division. Tobacco Division, Agricultural Marketing Service, U.S... 7 Agriculture 2 2010-01-01 2010-01-01 false Division. 29.16 Section 29.16 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections,...

  16. Entrainment of cell division in phytoplankton with dynamic energy budgets

    Science.gov (United States)

    Muller, Erik B.; Ananthasubramaniam, Bharath; Klanjšček, Tin; Nisbet, Roger M.

    2011-11-01

    We explore the entrainment behavior of cell division in phytoplankton in the context of Dynamic Energy Budget (DEB) theory. In particular, we explore the range of DEB and environmental parameter values within which a cell divides at regular intervals in a periodic light environment with abundant nutrients and investigate the impact of parameter values on the phase of cell division. We consider three types of cells that differ in the evolution of surface area to volume ratio during the cell cycle: cells with a constant shape (isomorphs), cells with a constant surface area (V0-morphs) and cells with a constant surface area to volume ratio (V1-morphs), the latter being the default choice in studies on the population dynamics of unicellular organisms because of its desirable mathematical implications. Only in isomorphs and V0-morphs, however, cell division can be entrained to a periodic light. Regular cell division in V1 is purely coincidental, as it depends on exact choices for parameter values. We attribute this to the fact that V1-morphs lack the negative feedback of size on the dynamics of reserves in V0-morphs and isomorphs. Because entrained isomorphs and V0-morphs divide during the dark hours in our simulations, these two shapes can represent the division behavior of phytoplankton species that complete the cell cycle during the night, such as dinoflagellates and coccolithophores. A description of the division behavior of species completing the cell cycle during the day, such as silicon dependent diatoms and cyanobacteria, requires a more complex model than used in this paper. Furthermore, we explore the robustness of our findings by randomizing model parameters and introducing unevenness in biomass separation between daughter cells during cell division. We conclude that especially the entrainment in V0-morphs is relatively insensitive to perturbations.

  17. How Mimas cleared the Cassini Division

    Science.gov (United States)

    Noyelles, Benoit; Baillie, Kevin; Lainey, Valery; Charnoz, Sebastien

    2016-10-01

    Recent measurements of the dissipation of Saturn (Lainey et al. 2016, Icarus, in press) combined with a theoretical study by Fuller et al. (2016, MNRAS) require to revisit the energy dissipation models in planetary systems and the way it affects their satellite system. In addition, the measurements of the large librations of Mimas (Tajeddine et al. 2014, Science) could point to a global ocean underneath the surface of the satellite. These results allowed us to refine the scenarios of the opening of the Cassini Division that we initially presented at the DPS 2012. Assuming a dissipation that is consistent with these latest results, we propose scenarios of combined evolutions of Mimas and the main rings of Saturn, that explain the current size and location of the Division, the excess of density in the outer B ring, a past episode of intense heating of Mimas required to create a global ocean, and its current eccentricity. For that, we show that a past resonance with Tethys increased the eccentricity of Mimas up to 0.2, possibly triggering the melting of Mimas and an episode of inward migration, which created the Cassini Division: the 2:1 resonance between Mimas and the rings pushed the ring material inner to accumulate in the B ring. Once its eccentricity is damped, Mimas resumes its outward migration, leading to a trapping into the current vertical resonance with Tethys. These results are supported by numerical simulations, in which Mimas is driven by the tides, and the rings are simulated with the 1-D hydrodynamical code Hydrorings (Charnoz et al., 2010, Nature). This study has been partially supported by the International Space Sciences Institute in Bern, Switzerland.

  18. The Optimizing Model and Its Solution for Making Train Working Graph with Computer on Separative Division of Double-Track Lines

    Institute of Scientific and Technical Information of China (English)

    Peng Qiyuan; Ju Tingying

    1994-01-01

    The authors specialize in the field of optimization and automatic programme of train working graph. In this paper, at frist, a mixed 0-1 integer programming model about this problem for double-track lines is set up, then the principle and process of solution are stated , with an application example put forward.

  19. 75 FR 16843 - Core Manufacturing, Multi-Plastics, Inc., Division, Sipco, Inc., Division, Including Leased...

    Science.gov (United States)

    2010-04-02

    ... Employment and Training Administration Core Manufacturing, Multi-Plastics, Inc., Division, Sipco, Inc..., 2009, applicable to workers of Core Manufacturing, Multi-Plastics, Inc., Division and Sipco, Inc... of Core Manufacturing, Multi-Plastics, Inc., Division and Sipco, Inc., Division, including...

  20. Terms in elliptic divisibility sequences divisible by their indices

    CERN Document Server

    Stange, Katherine E

    2010-01-01

    Let D = (D_n)_{n\\ge1} be an elliptic divisibility sequence. We study the set S(D) of indices n satisfying n | D_n. In particular, given an index n in S(D), we explain how to construct elements nd in S(D), where d is either a prime divisor of D_n, or d is the product of the primes in an aliquot cycle for D. We also give bounds for the exceptional indices that are not constructed in this way.

  1. Quantitative Classification of Forestry Division in Ceheng County

    Institute of Scientific and Technical Information of China (English)

    Hua; ZHAO; Yong; LIU; Longde; LIU; Jihui; SUN; Yongshun; GU

    2013-01-01

    To determine the main functions of regional forest and focus of forestry construction to form the regional forestry economy with characteristics and ecological service system pattern with obvious advantages,we select some indicators on Ceheng County in Guizhou Province, such as natural geography,socio-economic conditions,ecological environment and forests status. Using the quantitative classification method combining factor analysis and system clustering,we conduct quantitative county level forestry division. The results show that first using factor analysis to establish factor analysis model,and then using a handful of factors loading large amounts of information to carry out system clustering,is an effective quantitative classification method of forestry division,which can not only overcome the weakness of previous division mainly focusing on qualitative analysis,but also eliminate the correlation between indicators in the conventional classification methods; through the factor analysis of 30 indicators influencing the forestry development of each township in Ceheng County,the factor analysis model is established,6 factors loading 89. 94 5% of information amount are used to conduct system clustering on 14 townships in Ceheng County,and finally Ceheng County can be divided into five zones. This study not only enriches the theory of forestry division,but also provides reference for the forestry planning in Guizhou and division of related industries.

  2. Division G Commission 35: Stellar Constitution

    Science.gov (United States)

    Limongi, Marco; Lattanzio, John C.; Charbonnel, Corinne; Dominguez, Inma; Isern, Jordi; Karakas, Amanda; Leitherer, Claus; Marconi, Marcella; Shaviv, Giora; van Loon, Jacco

    2016-04-01

    Commission 35 (C35), ``Stellar Constitution'', consists of members of the International Astronomical Union whose research spans many aspects of theoretical and observational stellar physics and it is mainly focused on the comprehension of the properties of stars, stellar populations and galaxies. The number of members of C35 increased progressively over the last ten years and currently C35 comprises about 400 members. C35 was part of Division IV (Stars) until 2014 and then became part of Division G (Stars and Stellar Physics), after the main IAU reorganisation in 2015. Four Working Groups have been created over the years under Division IV, initially, and Division G later: WG on Active B Stars, WG on Massive Stars, WG on Abundances in Red Giant and WG on Chemically Peculiar and Related Stars. In the last decade the Commission had 4 presidents, Wojciech Dziembowski (2003-2006), Francesca D'Antona (2006-2009), Corinne Charbonnel (2009-2012) and Marco Limongi (2012-2015), who were assisted by an Organizing Committee (OC), usually composed of about 10 members, all of them elected by the C35 members and holding their positions for three years. The C35 webpage (http://iau-c35.stsci.edu) has been designed and continuously maintained by Claus Leitherer from the Space Telescope Institute, who deserves our special thanks. In addition to the various general information on the Commission structure and activities, it contains links to various resources, of interest for the members, such as stellar models, evolutionary tracks and isochrones, synthetic stellar populations, stellar yields and input physics (equation of state, nuclear cross sections, opacity tables), provided by various groups. The main activity of the C35 OC is that of evaluating, ranking and eventually supporting the proposals for IAU sponsored meetings. In the last decade the Commission has supported several meetings focused on topics more or less relevant to C35. Since the primary aim of this document is to

  3. Carrots and Sticks: A Comprehensive Business Model for the Successful Achievement of Energy Efficiency Resource Standards Environmental Energy Technologies DivisionMarch 2011

    Energy Technology Data Exchange (ETDEWEB)

    Satchwell, Andrew; Cappers, Peter; Goldman, Charles

    2011-03-22

    Energy efficiency resource standards (EERS) are a prominent strategy to potentially achieve rapid and aggressive energy savings goals in the U.S. As of December 2010, twenty-six U.S. states had some form of an EERS with savings goals applicable to energy efficiency (EE) programs paid for by utility customers. The European Union has initiated a similar type of savings goal, the Energy End-use Efficiency and Energy Services Directive, where it is being implemented in some countries through direct partnership with regulated electric utilities. U.S. utilities face significant financial disincentives under traditional regulation which affects the interest of shareholders and managers in aggressively pursuing cost-effective energy efficiency. Regulators are considering some combination of mandated goals ('sticks') and alternative utility business model components ('carrots' such as performance incentives) to align the utility's business and financial interests with state and federal energy efficiency public policy goals. European countries that have directed their utilities to administer EE programs have generally relied on non-binding mandates and targets; in the U.S., most state regulators have increasingly viewed 'carrots' as a necessary condition for successful achievement of energy efficiency goals and targets. In this paper, we analyze the financial impacts of an EERS on a large electric utility in the State of Arizona using a pro-forma utility financial model, including impacts on utility earnings, customer bills and rates. We demonstrate how a viable business model can be designed to improve the business case while retaining sizable ratepayer benefits. Quantifying these concerns and identifying ways they can be addressed are crucial steps in gaining the support of major stakeholder groups - lessons that can apply to other countries looking to significantly increase savings targets that can be achieved from their own utility

  4. A Magnetically-Switched, Rotating Black Hole Model For the Production of Extragalactic Radio Jets and the Fanaroff and Riley Class Division

    CERN Document Server

    Meier, D L

    1998-01-01

    A model is presented in which both Fanaroff and Riley class I and II extragalactic jets are produced by magnetized accretion disk coronae in the ergospheres of rotating black holes. While the jets are produced in the accretion disk itself, the output power still is an increasing function of the black hole angular momentum. For high enough spin, the black hole triggers the magnetic switch, producing highly-relativistic, kinetic-energy-dominated jets instead of Poynting-flux-dominated ones for lower spin. The coronal mass densities needed to trigger the switch at the observed FR break power are quite small ($\\sim 10^{-15} g cm^{-3}$), implying that the source of the jet material may be either a pair plasma or very tenuous electron-proton corona, not the main accretion disk itself. The model explains the differences in morphology and Mach number between FR I and II sources and the observed trend for massive galaxies to undergo the FR I/II transition at higher radio power. It also is consistent with the energy co...

  5. Critique and sensitivity analysis of the compensation function used in the LMS Hudson River striped bass models. Environmental Sciences Division publication No. 944

    Energy Technology Data Exchange (ETDEWEB)

    Van Winkle, W.; Christensen, S.W.; Kauffman, G.

    1976-12-01

    The description and justification for the compensation function developed and used by Lawler, Matusky and Skelly Engineers (LMS) (under contract to Consolidated Edison Company of New York) in their Hudson River striped bass models are presented. A sensitivity analysis of this compensation function is reported, based on computer runs with a modified version of the LMS completely mixed (spatially homogeneous) model. Two types of sensitivity analysis were performed: a parametric study involving at least five levels for each of the three parameters in the compensation function, and a study of the form of the compensation function itself, involving comparison of the LMS function with functions having no compensation at standing crops either less than or greater than the equilibrium standing crops. For the range of parameter values used in this study, estimates of percent reduction are least sensitive to changes in YS, the equilibrium standing crop, and most sensitive to changes in KXO, the minimum mortality rate coefficient. Eliminating compensation at standing crops either less than or greater than the equilibrium standing crops results in higher estimates of percent reduction. For all values of KXO and for values of YS and KX at and above the baseline values, eliminating compensation at standing crops less than the equilibrium standing crops results in a greater increase in percent reduction than eliminating compensation at standing crops greater than the equilibrium standing crops.

  6. The Commingled Division of Visual Attention.

    Directory of Open Access Journals (Sweden)

    Yuechuan Sun

    Full Text Available Many critical activities require visual attention to be distributed simultaneously among distinct tasks where the attended foci are not spatially separated. In our two experiments, participants performed a large number of trials where both a primary task (enumeration of spots and a secondary task (reporting the presence/absence or identity of a distinctive shape required the division of visual attention. The spots and the shape were commingled spatially and the shape appeared unpredictably on a relatively small fraction of the trials. The secondary task stimulus (the shape was reported in inverse proportion to the attentional load imposed by the primary task (enumeration of spots. When the shape did appear, performance on the primary task (enumeration suffered relative to when the shape was absent; both speed and accuracy were compromised. When the secondary task required identification in addition to detection, reaction times increased by about 200 percent. These results are broadly compatible with biased competition models of perceptual processing. An important area of application, where the commingled division of visual attention is required, is the augmented reality head-up display (AR-HUD. This innovation has the potential to make operating vehicles safer but our data suggest that there are significant concerns regarding driver distraction.

  7. Heparan sulfate and cell division

    Directory of Open Access Journals (Sweden)

    Porcionatto M.A.

    1999-01-01

    Full Text Available Heparan sulfate is a component of vertebrate and invertebrate tissues which appears during the cytodifferentiation stage of embryonic development. Its structure varies according to the tissue and species of origin and is modified during neoplastic transformation. Several lines of experimental evidence suggest that heparan sulfate plays a role in cellular recognition, cellular adhesion and growth control. Heparan sulfate can participate in the process of cell division in two distinct ways, either as a positive or negative modulator of cellular proliferation, or as a response to a mitogenic stimulus.

  8. A division's worth of data.

    Science.gov (United States)

    Pearce, Christopher; Shearer, Marianne; Gardner, Karina; Kelly, Jill

    2011-03-01

    Throughout the international community there is an increasing focus on the benefits of collecting, pooling and analysing patient data. General practice provides a great opportunity to create a comprehensive database of the Australian population as 90% of Australians visit their general practitioner each year and general practices are increasingly computerised. This article discusses the facilitatory role divisions of general practice can play in harnessing quality data from general practice and the benefits that may follow. It describes experience from 3 years of data pooling by the Melbourne East General Practice Network in Victoria and makes recommendations for other organisations interested in data collection.

  9. Code division multiple access (CDMA)

    CERN Document Server

    Buehrer, R Michael

    2006-01-01

    This book covers the basic aspects of Code Division Multiple Access or CDMA. It begins with an introduction to the basic ideas behind fixed and random access systems in order to demonstrate the difference between CDMA and the more widely understood TDMA, FDMA or CSMA. Secondly, a review of basic spread spectrum techniques are presented which are used in CDMA systems including direct sequence, frequency-hopping and time-hopping approaches. The basic concept of CDMA is presented, followed by the four basic principles of CDMA systems that impact their performance: interference averaging, universa

  10. Wildfires effects on soils: water repellency, NIR models and post-fire treatments. My personal view (SSS Division Outstanding ECS Award Lecture)

    Science.gov (United States)

    Arcenegui, Victoria

    2017-04-01

    I first was intrigued by fire, because all summers we had some of them in our location, and then I was involve in fire effects on soils. We had, and also have, a lot of question to answer. I am absolutely sure that soil science was my best choice. Soils are amazing, a lot of things are happening in soils. Soils and fire, are my main research topics. I studied the immediately effect of fire on soils, focus on the effect of fire in soil water repellency and aggregate stability. Two physical properties that are crucial to post-fire soil response. I also construct NIR models to know the maximum temperature reached in soils. It is well known that temperature is a key factor affecting soils properties. Then, it is a really important tool to predict the temperature reached in a soil after a wildfire. Currently, I am involve in a project to investigate what are the best post-fire treatments in our soils and how this treatments affects soil properties.

  11. Harnessing single cell sorting to identify cell division genes and regulators in bacteria.

    Directory of Open Access Journals (Sweden)

    Catherine Burke

    Full Text Available Cell division is an essential cellular process that requires an array of known and unknown proteins for its spatial and temporal regulation. Here we develop a novel, high-throughput screening method for the identification of bacterial cell division genes and regulators. The method combines the over-expression of a shotgun genomic expression library to perturb the cell division process with high-throughput flow cytometry sorting to screen many thousands of clones. Using this approach, we recovered clones with a filamentous morphology for the model bacterium, Escherichia coli. Genetic analysis revealed that our screen identified both known cell division genes, and genes that have not previously been identified to be involved in cell division. This novel screening strategy is applicable to a wide range of organisms, including pathogenic bacteria, where cell division genes and regulators are attractive drug targets for antibiotic development.

  12. On measures of non-Markovianity: divisibility vs. Markovianity

    CERN Document Server

    Chruściński, Dariusz

    2011-01-01

    We analyze two recently proposed measure of non-Markovianity: one based on the concept of divisibility of the dynamical map and the other one based on distinguishability of quantum states. We provide a toy model to show that these two measures need not agree. Finally, we discuss possible generalizations and intricate relations between these measures.

  13. Measures of non-Markovianity: Divisibility versus backflow of information

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej; Rivas, Ángel

    2011-05-01

    We analyze two recently proposed measures of non-Markovianity: one based on the concept of divisibility of the dynamical map and the other one based on distinguishability of quantum states. We provide a model to show that these two measures need not agree. In addition, we discuss possible generalizations and intricate relations between these measures.

  14. Leading by Example? ALA Division Publications, Open Access, and Sustainability

    Science.gov (United States)

    Hall, Nathan; Arnold-Garza, Sara; Gong, Regina; Shorish, Yasmeen

    2016-01-01

    This investigation explores scholarly communication business models in American Library Association (ALA) division peer-reviewed academic journals. Previous studies reveal the numerous issues organizations and publishers face in the academic publishing environment. Through an analysis of documented procedures, policies, and finances of five ALA…

  15. Leading by Example? ALA Division Publications, Open Access, and Sustainability

    Science.gov (United States)

    Hall, Nathan; Arnold-Garza, Sara; Gong, Regina; Shorish, Yasmeen

    2016-01-01

    This investigation explores scholarly communication business models in American Library Association (ALA) division peer-reviewed academic journals. Previous studies reveal the numerous issues organizations and publishers face in the academic publishing environment. Through an analysis of documented procedures, policies, and finances of five ALA…

  16. Cell division and death inhibit glassy behaviour of confluent tissues

    CERN Document Server

    Matoz-Fernandez, D A; Sknepnek, Rastko; Barrat, J L; Henkes, S

    2016-01-01

    We investigate the effects of cell division and apopotosis on collective dynamics in two-dimensional epithelial tissues. Our model includes three key ingredients observed across many epithelia, namely cell-cell adhesion, cell death and a cell division process that depends on the surrounding environment. We show a rich non-equilibrium phase diagram depending on the ratio of cell death to cell division and on the adhesion strength. For large apopotosis rates, cells die out and the tissue disintegrates. As the death rate decreases, however, we show, consecutively, the existence of a gas-like phase, a gel-like phase, and a dense confluent (tissue) phase. Most striking is the observation that the tissue is self-melting through its own internal activity, ruling out the existence of any glassy phase.

  17. A new synchronization scheme based on time division multiplexing and wavelength division multiplexing technology for practical quantum key distribution system

    Institute of Scientific and Technical Information of China (English)

    Zhong Ping-Ping; Zhang Hua-Ni; Wang Jin-Dong; Qin Xiao-Juan; Wei zheng-Jun; Chen Shuai; Liu Song-Hao

    2011-01-01

    Three clock synchronization schemes for a quantum key distribution system are compared experimentally through the outdoor fibre and the interaction physical model of the the clock signal and the the quantum signal in the quantum key distribution system is analysed to propose a new synchronization scheme based on time division multiplexing and wavelength division multiplexing technology to reduce quantum bits error rates under some transmission rate conditions.The proposed synchronization scheme can not only completely eliminate noise photons from the bright background light of the the clock signal, but also suppress the fibre nonlinear crosstalk.

  18. Chemical Technology Division annual technical report 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-06-01

    The Chemical Technology (CMT) Division is a diverse technical organization with principal emphases in environmental management and development of advanced energy sources. The Division conducts research and development in three general areas: (1) development of advanced power sources for stationary and transportation applications and for consumer electronics, (2) management of high-level and low-level nuclear wastes and hazardous wastes, and (3) electrometallurgical treatment of spent nuclear fuel. The Division also performs basic research in catalytic chemistry involving molecular energy resources, mechanisms of ion transport in lithium battery electrolytes, and the chemistry of technology-relevant materials and electrified interfaces. In addition, the Division operates the Analytical Chemistry Laboratory, which conducts research in analytical chemistry and provides analytical services for programs at Argonne National Laboratory (ANL) and other organizations. Technical highlights of the Division`s activities during 1997 are presented.

  19. Cell Division, Differentiation and Dynamic Clustering

    CERN Document Server

    Kaneko, K; Kaneko, Kunihiko; Yomo, Tetsuya

    1993-01-01

    A novel mechanism for cell differentiation is proposed, based on the dynamic clustering in a globally coupled chaotic system. A simple model with metabolic reaction, active transport of chemicals from media, and cell division is found to show three successive stages with the growth of the number of cells; coherent growth, dynamic clustering, and fixed cell differentiation. At the last stage, disparity in activities, germ line segregation, somatic cell differentiation, and homeochaotic stability against external perturbation are found. Our results, in consistency with the experiments of the preceding paper, imply that cell differentiation can occur without a spatial pattern. From dynamical systems viewpoint, the new concept of ``open chaos" is proposed, as a novel and general scenario for systems with growing numbers of elements, also seen in economics and sociology.A

  20. Using Live-Cell Markers in Maize to Analyze Cell Division Orientation and Timing.

    Science.gov (United States)

    Rasmussen, Carolyn G

    2016-01-01

    Recently developed live-cell markers provide an opportunity to explore the dynamics and localization of proteins in maize, an important crop and model for monocot development. A step-by-step method is outlined for observing and analyzing the process of division in maize cells. The steps include plant growth conditions, sample preparation, time-lapse setup, and calculation of division rates.

  1. DESIGN AND REALISATION OF MODELLING AND FINITE ELEMENT DIVISION ON SHIP FLANGED BRACKET%船舶折边肘板建模与有限元划分的设计与实现

    Institute of Scientific and Technical Information of China (English)

    许一敏; 冷文浩; 周炜; 田志峰; 程成

    2013-01-01

    Bracket is a common component for connection in ship structure and other steel structures,and flanged bracket is frequently used in flanged docking for main ship components.In order to enhance the efficiency of modelling flanged bracket,we design the parametric 3D solid modelling process for flanged bracket.According to the modelling process,we discuss the methods of parametric bracket contour generation and flanges information storage,provide the algorithms for coordinate transformation and flange rotation,and study the objectoriented programming and finite element method.Moreover,we import MSC.Patran for mesh division,realise the transformation from CAD model to finite element analysis model,and present PDM integration.Taking AutoCAD as the development platform,VS.Net as the programming environment,and ObjectARX as the development tool,we implement the object-oriented parametric solid modelling system for flanged bracket.%肘板是船舶结构及其它钢结构中常用的连接构件,折边肘板经常用于船舶主构件的折边对接中.为了提高折边肘板建模的效率,设计折边肘板参数化三维实体造型过程;根据造型过程,探讨肘板轮廓参数化生成及折边信息存储方法;给出坐标转换及折边旋转算法;研究面向对象与有限元方法;并导入MSC.Patran进行网格划分,实现CAD模型到有限元分析模型的转化;给出PDM的集成:以AutoCAD为开发平台,VS.Net为编程环境,ObiectARX为开发工具,实现了面向对象的折边肘板参数化实体造型.

  2. Divisions Panel Discussion: Astronomy for Development

    Science.gov (United States)

    Govender, Kevin; Hemenway, Mary Kay; Wolter, Anna; Haghighipour, Nader; Yan, Yihua; van Dishoeck, E. F.; Silva, David; Guinan, Edward

    2016-10-01

    The main purpose of this panel discussion was to encourage conversation around potential collaborations between the IAU Office of Astronomy for Development (OAD) and IAU Divisions. The discussion was facilitated by the OAD and the conversation revolved mainly around two questions: (i) What should the OAD be doing to enhance the work of the Divisions? (ii) What could the Divisions (both members and respective scientific discipline in general) contribute towards the implementation of the IAU strategic plan?

  3. Major Programs | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention supports major scientific collaborations, research networks, investigator-initiated grants, postdoctoral training, and specialized resources across the United States. |

  4. Power Efficient Division and Square Root Unit

    DEFF Research Database (Denmark)

    Liu, Wei; Nannarelli, Alberto

    2012-01-01

    shows that division and square root units based on the digit-recurrence algorithm offer the best tradeoff delay-area-power. Moreover, the two operations can be combined in a single unit. Here, we present a radix-16 combined division and square root unit obtained by overlapping two radix-4 stages......Although division and square root are not frequent operations, most processors implement them in hardware to not compromise the overall performance. Two classes of algorithms implement division or square root: digit-recurrence and multiplicative (e.g., Newton-Raphson) algorithms. Previous work...

  5. Fair division theory and climate change policy

    Energy Technology Data Exchange (ETDEWEB)

    Helm, C. [Technical University Darmstadt (Germany). Department of Law and Economics

    2008-09-30

    This paper analyzes the fair division of common property resources when monetary compensations are feasible. A prominent example is the fair division of the atmosphere's limited absorptive capacity for greenhouse gases. I propose a solution that is Pareto efficient and satisfies the axiomatic fair division criteria of individual rationality, stand-alone upper bound, and a version of envy-freeness. The latter criterion is adapted to problems where monetary compensations can be used to facilitate the fair division of the common resource. Applied to climate change, the solution implies that developing countries should participate in emission reduction efforts, but should be fully compensated for their incremental abatement costs.

  6. Division Unit for Binary Integer Decimals

    DEFF Research Database (Denmark)

    Lang, Tomas; Nannarelli, Alberto

    2009-01-01

    -recurrence algorithm to BID representation and implement the division unit in standard cell technology. The implementation of the proposed BID division unit is compared to that of a BCD based unit implementing the same algorithm. The comparison shows that for normalized operands the BID unit has the same latency......In this work, we present a radix-10 division unit that is based on the digit-recurrence algorithm and implements binary encodings (binary integer decimal or BID) for significands. Recent decimal division designs are all based on the binary coded decimal (BCD) encoding. We adapt the radix-10 digit...

  7. Division Algebras and Quantum Theory

    CERN Document Server

    Baez, John C

    2011-01-01

    Quantum theory may be formulated using Hilbert spaces over any of the three associative normed division algebras: the real numbers, the complex numbers and the quaternions. Indeed, these three choices appear naturally in a number of axiomatic approaches. However, there are internal problems with real or quaternionic quantum theory. Here we argue that these problems can be resolved if we treat real, complex and quaternionic quantum theory as part of a unified structure. Dyson called this structure the "three-fold way". It is perhaps easiest to see it in the study of irreducible unitary representations of groups on complex Hilbert spaces. These representations come in three kinds: those that are not isomorphic to their own dual (the truly "complex" representations), those that are self-dual thanks to a symmetric bilinear pairing (which are "real", in that they are the complexifications of representations on real Hilbert spaces), and those that are self-dual thanks to an antisymmetric bilinear pairing (which are...

  8. 客运专线与既有线合理分工模型%Mathematical Model and Algorithm for Rational Division of Labor between Passenger Dedicated Line and Conventional Rail

    Institute of Scientific and Technical Information of China (English)

    张迦南; 赵鹏; 纪丽君

    2011-01-01

    This paper analyzes the railway system with transport demand under conditions of passenger dedicated line parallel with the conventional rail, and simulates the system structure based on hypothesis. Modeling the Rational Division of Labor between Passenger Dedicated Line and Conventional Rail Problem (RDLP&CP) with an objective of minimizing the total cost of the railway system, taking into account the fixed and variable costs of trains, and the cost of trains interchange between passenger dedicated line and conventional rail, and the station stop cost which stands for the benefits of passengers. Considering the schedule of stops, route and transport plan of trains as decision variables, the constraints are constructed according to the capability of stations and lines based on the objective of meeting the transport demand from passengers and commodities. The model integrates optimized the schedule of stop, route and transport amount of trains.Then an algorithm combined with the LINGO software is designed. Finally, a case study based on a long railway corridor (adapted from the Beijing-Guangzhou corridor) is presented to illustrate the capabilities of the methodology. The results show that this model can be used to propose the rational division of labor between passenger dedicated line and conventional railway.%分析客运专线与既有线并行条件下的列车运行系统,在抽象和假设的基础上模拟系统结构.以总成本最小化为出发点,将列车运行的固定成本和变动成本、列车在客运专线与既有线之间的转线成本和代表客户利益的停站成本共同纳入目标体系,构建客运专线与既有线合理分工问题的非线性混合整数规划模型.模型以列车停站、区段选择及客流运输方案为决策变量,在铁路客、货运输需求基础上,将车站、线路能力约束与铁路运输要求相结合构造约束条件,实现列车停站、路径选择及流量分配方案的一体化编制.

  9. Asymmetric cell division of T cells upon antigen presentation uses multiple conserved mechanisms.

    Science.gov (United States)

    Oliaro, Jane; Van Ham, Vanessa; Sacirbegovic, Faruk; Pasam, Anupama; Bomzon, Ze'ev; Pham, Kim; Ludford-Menting, Mandy J; Waterhouse, Nigel J; Bots, Michael; Hawkins, Edwin D; Watt, Sally V; Cluse, Leonie A; Clarke, Chris J P; Izon, David J; Chang, John T; Thompson, Natalie; Gu, Min; Johnstone, Ricky W; Smyth, Mark J; Humbert, Patrick O; Reiner, Steven L; Russell, Sarah M

    2010-07-01

    Asymmetric cell division is a potential means by which cell fate choices during an immune response are orchestrated. Defining the molecular mechanisms that underlie asymmetric division of T cells is paramount for determining the role of this process in the generation of effector and memory T cell subsets. In other cell types, asymmetric cell division is regulated by conserved polarity protein complexes that control the localization of cell fate determinants and spindle orientation during division. We have developed a tractable, in vitro model of naive CD8(+) T cells undergoing initial division while attached to dendritic cells during Ag presentation to investigate whether similar mechanisms might regulate asymmetric division of T cells. Using this system, we show that direct interactions with APCs provide the cue for polarization of T cells. Interestingly, the immunological synapse disseminates before division even though the T cells retain contact with the APC. The cue from the APC is translated into polarization of cell fate determinants via the polarity network of the Par3 and Scribble complexes, and orientation of the mitotic spindle during division is orchestrated by the partner of inscuteable/G protein complex. These findings suggest that T cells have selectively adapted a number of evolutionarily conserved mechanisms to generate diversity through asymmetric cell division.

  10. Oriented cell division affects the global stress and cell packing geometry of a monolayer under stretch.

    Science.gov (United States)

    Xu, Guang-Kui; Liu, Yang; Zheng, Zhaoliang

    2016-02-08

    Cell division plays a vital role in tissue morphogenesis and homeostasis, and the division plane is crucial for cell fate. For isolated cells, extensive studies show that the orientation of divisions is sensitive to cell shape and the direction of extrinsic mechanical forces. However, it is poorly understood that how the cell divides within a cell monolayer and how the local stress change, due to the division, affects the global stress of epithelial monolayers. Here, we use the vertex dynamics models to investigate the effects of division orientation on the configurations and mechanics of a cell monolayer under stretch. We examine three scenarios of the divisions: dividing along the stretch axis, dividing along the geometric long axis of cells, and dividing at a random angle. It is found that the division along the long cell axis can induce the minimal energy difference, and the global stress of the monolayer after stretch releases more rapidly in this case. Moreover, the long-axis division can result in more random cell orientations and more isotropic cell shapes within the monolayer, comparing with other two cases. This study helps understand the division orientation of cells within a monolayer under mechanical stimuli, and may shed light on linking individual cell's behaviors to the global mechanics and patterns of tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Emergence of homeostatic epithelial packing and stress dissipation through divisions oriented along the long cell axis

    Science.gov (United States)

    Wyatt, Tom P. J.; Harris, Andrew R.; Lam, Maxine; Cheng, Qian; Bellis, Julien; Dimitracopoulos, Andrea; Kabla, Alexandre J.; Charras, Guillaume T.; Baum, Buzz

    2015-01-01

    Cell division plays an important role in animal tissue morphogenesis, which depends, critically, on the orientation of divisions. In isolated adherent cells, the orientation of mitotic spindles is sensitive to interphase cell shape and the direction of extrinsic mechanical forces. In epithelia, the relative importance of these two factors is challenging to assess. To do this, we used suspended monolayers devoid of ECM, where divisions become oriented following a stretch, allowing the regulation and function of epithelial division orientation in stress relaxation to be characterized. Using this system, we found that divisions align better with the long, interphase cell axis than with the monolayer stress axis. Nevertheless, because the application of stretch induces a global realignment of interphase long axes along the direction of extension, this is sufficient to bias the orientation of divisions in the direction of stretch. Each division redistributes the mother cell mass along the axis of division. Thus, the global bias in division orientation enables cells to act collectively to redistribute mass along the axis of stretch, helping to return the monolayer to its resting state. Further, this behavior could be quantitatively reproduced using a model designed to assess the impact of autonomous changes in mitotic cell mechanics within a stretched monolayer. In summary, the propensity of cells to divide along their long axis preserves epithelial homeostasis by facilitating both stress relaxation and isotropic growth without the need for cells to read or transduce mechanical signals. PMID:25908119

  12. Physics Division annual report 2004.

    Energy Technology Data Exchange (ETDEWEB)

    Glover, J.

    2006-04-06

    This report highlights the research performed in 2004 in the Physics Division of Argonne National Laboratory. The Division's programs include operation of ATLAS as a national user facility, nuclear structure and reaction research, nuclear theory, medium energy nuclear research and accelerator research and development. The intellectual challenges of this research represent some of the most fundamental challenges in modern science, shaping our understanding of both tiny objects at the center of the atom and some of the largest structures in the universe. A great strength of these efforts is the critical interplay of theory and experiment. Notable results in research at ATLAS include a measurement of the charge radius of He-6 in an atom trap and its explanation in ab-initio calculations of nuclear structure. Precise mass measurements on critical waiting point nuclei in the rapid-proton-capture process set the time scale for this important path in nucleosynthesis. An abrupt fall-off was identified in the subbarrier fusion of several heavy-ion systems. ATLAS operated for 5559 hours of research in FY2004 while achieving 96% efficiency of beam delivery for experiments. In Medium Energy Physics, substantial progress was made on a long-term experiment to search for the violation of time-reversal invariance using trapped Ra atoms. New results from HERMES reveal the influence of quark angular momentum. Experiments at JLAB search for evidence of color transparency in rho-meson production and study the EMC effect in helium isotopes. New theoretical results include a Poincare covariant description of baryons as composites of confined quarks and non-point-like diquarks. Green's function Monte Carlo techniques give accurate descriptions of the excited states of light nuclei and these techniques been extended to scattering states for astrophysics studies. A theoretical description of the phenomena of proton radioactivity has been extended to triaxial nuclei. Argonne

  13. "American Gothic" and the Division of Labor.

    Science.gov (United States)

    Saunders, Robert J.

    1987-01-01

    Provides historical review of gender-based division of labor. Argues that gender-based division of labor served a purpose in survival of tribal communities but has lost meaning today and may be a handicap to full use of human talent and ability in the arts. There is nothing in various art forms which make them more appropriate for males or…

  14. Distinguishing division algebras by finite splitting fields

    CERN Document Server

    Krashen, Daniel

    2010-01-01

    This paper is concerned with the problem of determining the number of division algebras which share the same collection of finite splitting fields. As a corollary we are able to determine when two central division algebras may be distinguished by their finite splitting fields over certain fields.

  15. On Durkheim's Explanation of Division of Labor.

    Science.gov (United States)

    Rueschemeyer, Dietrich

    1982-01-01

    In De la Division du Travail Social, Durkheim's causal explanation for secular increases in the division of labor and the differentiation of social structure is flawed. His metatheoretical concerns expressed in the critique of utilitarian social theory flawed his contributions to a causal explanation of social differentiation. (Author/AM)

  16. Introduction to JPL's Mechanical Systems Division

    Science.gov (United States)

    Short, Kendra

    2007-01-01

    This slide presentation reviews the work of the Mechanical Systems Division. It reviews the projects, both past and current that the engineers of this division have worked on. It also reviews the work environment as an exciting place for the entry level engineer.

  17. The Division of Labor as Social Interaction

    Science.gov (United States)

    Freidson, Eliot

    1976-01-01

    Three different principles and ideologies by which the division of labor can be organized are sketched, along with their consequences for variation in structure and content. It is noted that the reality of the division of labor lies in the social interaction of its participants. (Author/AM)

  18. Teaching Cell Division: Basics and Recommendations.

    Science.gov (United States)

    Smith, Mike U.; Kindfield, Ann C. H.

    1999-01-01

    Presents a concise overview of cell division that includes only the essential concepts necessary for understanding genetics and evolution. Makes recommendations based on published research and teaching experiences that can be used to judge the merits of potential activities and materials for teaching cell division. Makes suggestions regarding the…

  19. Polarized Cell Division of Chlamydia trachomatis

    Science.gov (United States)

    Abdelrahman, Yasser; Ouellette, Scot P.; Belland, Robert J.; Cox, John V.

    2016-01-01

    Bacterial cell division predominantly occurs by a highly conserved process, termed binary fission, that requires the bacterial homologue of tubulin, FtsZ. Other mechanisms of bacterial cell division that are independent of FtsZ are rare. Although the obligate intracellular human pathogen Chlamydia trachomatis, the leading bacterial cause of sexually transmitted infections and trachoma, lacks FtsZ, it has been assumed to divide by binary fission. We show here that Chlamydia divides by a polarized cell division process similar to the budding process of a subset of the Planctomycetes that also lack FtsZ. Prior to cell division, the major outer-membrane protein of Chlamydia is restricted to one pole of the cell, and the nascent daughter cell emerges from this pole by an asymmetric expansion of the membrane. Components of the chlamydial cell division machinery accumulate at the site of polar growth prior to the initiation of asymmetric membrane expansion and inhibitors that disrupt the polarity of C. trachomatis prevent cell division. The polarized cell division of C. trachomatis is the result of the unipolar growth and FtsZ-independent fission of this coccoid organism. This mechanism of cell division has not been documented in other human bacterial pathogens suggesting the potential for developing Chlamydia-specific therapeutic treatments. PMID:27505160

  20. Materials Sciences Division 1990 annual report

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

    This report is the Materials Sciences Division`s annual report. It contains abstracts describing materials research at the National Center for Electron Microscopy, and for research groups in metallurgy, solid-state physics, materials chemistry, electrochemical energy storage, electronic materials, surface science and catalysis, ceramic science, high tc superconductivity, polymers, composites, and high performance metals.

  1. Hemispheric Division of Labour in Reading

    Science.gov (United States)

    Shillcock, Richard C.; McDonald, Scott A.

    2005-01-01

    We argue that the reading of words and text is fundamentally conditioned by the splitting of the fovea and the hemispheric division of the brain, and, furthermore, that the equitable division of labour between the hemispheres is a characteristic of normal visual word recognition. We report analyses of a representative corpus of the eye fixations…

  2. Nicely semiramified division algebras over Henselian fields

    Directory of Open Access Journals (Sweden)

    Karim Mounirh

    2005-01-01

    Full Text Available This paper deals with the structure of nicely semiramified valued division algebras. We prove that any defectless finite-dimensional central division algebra over a Henselian field E with an inertial maximal subfield and a totally ramified maximal subfield (not necessarily of radical type (resp., split by inertial and totally ramified field extensions of E is nicely semiramified.

  3. Cognitive and Neural Sciences Division, 1991 Programs.

    Science.gov (United States)

    Vaughan, Willard S., Ed.

    This report documents research and development performed under the sponsorship of the Cognitive and Neural Sciences Division of the Office of Naval Research in fiscal year 1991. It provides abstracts (title, principal investigator, project code, objective, approach, progress, and related reports) of projects of three program divisions (cognitive…

  4. Polarized Cell Division of Chlamydia trachomatis.

    Science.gov (United States)

    Abdelrahman, Yasser; Ouellette, Scot P; Belland, Robert J; Cox, John V

    2016-08-01

    Bacterial cell division predominantly occurs by a highly conserved process, termed binary fission, that requires the bacterial homologue of tubulin, FtsZ. Other mechanisms of bacterial cell division that are independent of FtsZ are rare. Although the obligate intracellular human pathogen Chlamydia trachomatis, the leading bacterial cause of sexually transmitted infections and trachoma, lacks FtsZ, it has been assumed to divide by binary fission. We show here that Chlamydia divides by a polarized cell division process similar to the budding process of a subset of the Planctomycetes that also lack FtsZ. Prior to cell division, the major outer-membrane protein of Chlamydia is restricted to one pole of the cell, and the nascent daughter cell emerges from this pole by an asymmetric expansion of the membrane. Components of the chlamydial cell division machinery accumulate at the site of polar growth prior to the initiation of asymmetric membrane expansion and inhibitors that disrupt the polarity of C. trachomatis prevent cell division. The polarized cell division of C. trachomatis is the result of the unipolar growth and FtsZ-independent fission of this coccoid organism. This mechanism of cell division has not been documented in other human bacterial pathogens suggesting the potential for developing Chlamydia-specific therapeutic treatments.

  5. Israel: the Division before Peace

    Directory of Open Access Journals (Sweden)

    Ferran Izquierdo Brichs

    2000-01-01

    Full Text Available The process of the Middle East peace negotiations at the beginning of the 1990s has its roots in the changes in the international system and in Israeli society. The end of the Cold War, the Gulf War in 1990-1991 and globalization forced all the region’s actors to resituate themselves within the new international context. However, Israeli society neither experienced the international changes in the same way as its neighbors nor did it undergo the same evolutionduring the conflict with the Arabs. Because of this, the debate over peace and the future of the occupied territories became a factor for political and ideological division. Influencing this debate were revised conceptions on security, the economy, and the role Israel should play in the world. The Middle East peace talks began because the strongest side in the conflict, Israel’s Labor government, came to perceive that the maintenance of the status quo was negative forits interests. From the Israeli point of view, the conflict had long been considered a zero-sum game despite the Palestinian’s compromises since the construction of the Palestinian State involved handing over part of the territory claimed by the Jews. Recent changes in the perceptions of Israeli’s own interests, though, led some sectors of Jewish society to re-think and diminish the supposed incompatibility between Palestine nationalism and Zionism, which then opened the doors towards peace. For the Labor government, the territorial occupation of all Palestine was no longer a central objective. In fact, the basic interests of the Labor party’s policies shifted due to the globalization of the international system. For Likud and the Zionist revisionists, however, the occupation and the colonization of Eretz Israel still form the basic ideology of the State –of its reason for being– for which even today both are associated with the national interest, together with Israel’s very survival. Seen this way, Israel

  6. Gravity and the orientation of cell division

    Science.gov (United States)

    Helmstetter, C. E.

    1997-01-01

    A novel culture system for mammalian cells was used to investigate division orientations in populations of Chinese hamster ovary cells and the influence of gravity on the positioning of division axes. The cells were tethered to adhesive sites, smaller in diameter than a newborn cell, distributed over a nonadhesive substrate positioned vertically. The cells grew and divided while attached to the sites, and the angles and directions of elongation during anaphase, projected in the vertical plane, were found to be random with respect to gravity. However, consecutive divisions of individual cells were generally along the same axis or at 90 degrees to the previous division, with equal probability. Thus, successive divisions were restricted to orthogonal planes, but the choice of plane appeared to be random, unlike the ordered sequence of cleavage orientations seen during early embryo development.

  7. 1998 Chemical Technology Division Annual Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ackerman, J.P.; Einziger, R.E.; Gay, E.C.; Green, D.W.; Miller, J.F.

    1999-08-06

    The Chemical Technology (CMT) Division is a diverse technical organization with principal emphases in environmental management and development of advanced energy sources. The Division conducts research and development in three general areas: (1) development of advanced power sources for stationary and transportation applications and for consumer electronics, (2) management of high-level and low-level nuclear wastes and hazardous wastes, and (3) electrometallurgical treatment of spent nuclear fuel. The Division also performs basic research in catalytic chemistry involving molecular energy resources, mechanisms of ion transport in lithium battery electrolytes, and the chemistry of technology-relevant materials. In addition, the Division operates the Analytical Chemistry Laboratory, which conducts research in analytical chemistry and provides analytical services for programs at Argonne National Laboratory (ANL) and other organizations. Technical highlights of the Division's activities during 1998 are presented.

  8. Effect of the Min System on Timing of Cell Division in Escherichia coli

    Science.gov (United States)

    Jia, Shuxin; Keilberg, Daniela; Hot, Edina; Thanbichler, Martin; Søgaard-Andersen, Lotte; Lenz, Peter

    2014-01-01

    In Escherichia coli the Min protein system plays an important role in positioning the division site. We show that this system also has an effect on timing of cell division. We do this in a quantitative way by measuring the cell division waiting time (defined as time difference between appearance of a division site and the division event) and the Z-ring existence time. Both quantities are found to be different in WT and cells without functional Min system. We develop a series of theoretical models whose predictions are compared with the experimental findings. Continuous improvement leads to a final model that is able to explain all relevant experimental observations. In particular, it shows that the chromosome segregation defect caused by the absence of Min proteins has an important influence on timing of cell division. Our results indicate that the Min system affects the septum formation rate. In the absence of the Min proteins this rate is reduced, leading to the observed strongly randomized cell division events and the longer division waiting times. PMID:25090009

  9. Physics division annual report 1999

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, K., ed.; Physics

    2000-12-06

    This report summarizes the research performed in the past year in the Argonne Physics Division. The Division's programs include operation of ATLAS as a national heavy-ion user facility, nuclear structure and reaction research with beams of heavy ions, accelerator research and development especially in superconducting radio frequency technology, nuclear theory and medium energy nuclear physics. The Division took significant strides forward in its science and its initiatives for the future in the past year. Major progress was made in developing the concept and the technology for the future advanced facility of beams of short-lived nuclei, the Rare Isotope Accelerator. The scientific program capitalized on important instrumentation initiatives with key advances in nuclear science. In 1999, the nuclear science community adopted the Argonne concept for a multi-beam superconducting linear accelerator driver as the design of choice for the next major facility in the field a Rare Isotope Accelerator (WA) as recommended by the Nuclear Science Advisory Committee's 1996 Long Range Plan. Argonne has made significant R&D progress on almost all aspects of the design concept including the fast gas catcher (to allow fast fragmentation beams to be stopped and reaccelerated) that in large part defined the RIA concept the superconducting rf technology for the driver accelerator, the multiple-charge-state concept (to permit the facility to meet the design intensity goals with existing ion-source technology), and designs and tests of high-power target concepts to effectively deal with the full beam power of the driver linac. An NSAC subcommittee recommended the Argonne concept and set as tie design goal Uranium beams of 100-kwatt power at 400 MeV/u. Argonne demonstrated that this goal can be met with an innovative, but technically in-hand, design. The heavy-ion research program focused on GammaSphere, the premier facility for nuclear structure gamma-ray studies. One example

  10. Physics division annual report 1999

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, K., ed.; Physics

    2000-12-06

    This report summarizes the research performed in the past year in the Argonne Physics Division. The Division's programs include operation of ATLAS as a national heavy-ion user facility, nuclear structure and reaction research with beams of heavy ions, accelerator research and development especially in superconducting radio frequency technology, nuclear theory and medium energy nuclear physics. The Division took significant strides forward in its science and its initiatives for the future in the past year. Major progress was made in developing the concept and the technology for the future advanced facility of beams of short-lived nuclei, the Rare Isotope Accelerator. The scientific program capitalized on important instrumentation initiatives with key advances in nuclear science. In 1999, the nuclear science community adopted the Argonne concept for a multi-beam superconducting linear accelerator driver as the design of choice for the next major facility in the field a Rare Isotope Accelerator (WA) as recommended by the Nuclear Science Advisory Committee's 1996 Long Range Plan. Argonne has made significant R&D progress on almost all aspects of the design concept including the fast gas catcher (to allow fast fragmentation beams to be stopped and reaccelerated) that in large part defined the RIA concept the superconducting rf technology for the driver accelerator, the multiple-charge-state concept (to permit the facility to meet the design intensity goals with existing ion-source technology), and designs and tests of high-power target concepts to effectively deal with the full beam power of the driver linac. An NSAC subcommittee recommended the Argonne concept and set as tie design goal Uranium beams of 100-kwatt power at 400 MeV/u. Argonne demonstrated that this goal can be met with an innovative, but technically in-hand, design. The heavy-ion research program focused on GammaSphere, the premier facility for nuclear structure gamma-ray studies. One example

  11. Physics Division research and development

    Science.gov (United States)

    Hollen, G. Y.; Schappert, G. T.

    1994-07-01

    This report discusses its following topics: Recent Weapons-Physics Experiments on the Pegasus II Pulsed Power Facility; Operation of a Large-Scale Plasma Source Ion Implantation Experiment; Production of Charm and Beauty Mesons at Fermilab Sudbury Neutrino Observatory; P-Division's Essential Role in the Redirected Inertial Confinement Fusion Program; Trident Target Physics Program; Comparative Studies of Brain Activation with Magnetocephalography and Functional Magnetic Resonance Imaging; Cellular Communication, Interaction of G-Proteins, and Single-Photon Detection; Nuclear Magnetic Resonance Studies of Oxygen-doped La2CuO(4+delta) Thermoacoustic Engines; A Shipborne Raman Water-Vapor Lidar for the Central Pacific Experiment; Angara-5 Pinch Temperature Verification with Time-resolved Spectroscopy; Russian Collaborations on Megagauss Magnetic Fields and Pulsed-Power Applications; Studies of Energy Coupling from Underground Explosions; Trapping and Cooling Large Numbers of Antiprotons: A First Step Toward the Measurement of Gravity on Antimatter; and Nuclear-Energy Production Without a Long-Term High-Level Waste Stream.

  12. EDH 'Millionaire' in PS Division

    CERN Multimedia

    2001-01-01

    Christmas cheer! Left to right: Gerard Lobeau receives a bottle of Champagne from Derek Mathieson and Jurgen De Jonghe in recognition of EDH's millionth document. At 14:33 on Monday 3 December a technician in PS division, Gerard Lobeau, unwittingly became part of an important event in the life of CERN's Electronic Document Handling system (EDH). While ordering some pieces of aluminum for one of the PS's 10Mhz RF cavities, he created EDH document number 1,000,000. To celebrate the event Derek Mathieson (EDH Project Leader) and Jurgen De Jonghe (Original EDH Project Leader) presented Mr Lobeau with a bottle of champagne. As with 93% of material requests, Mr Lobeau's order was delivered within 24 hours. 'I usually never win anything' said Mr Lobeau as he accepted his prize, 'I initially though there may have been a problem with EDH when the document number had so many zeros in it, and was then surprised to get a phone call from you a few minutes later.' The EDH team had been monitoring the EDH document number ...

  13. 49 CFR 1242.03 - Made by accounting divisions.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Made by accounting divisions. 1242.03 Section 1242... accounting divisions. The separation shall be made by accounting divisions, where such divisions are maintained, and the aggregate of the accounting divisions reported for the quarter and for the year....

  14. M-cadherin-mediated intercellular interactions activate satellite cell division.

    Science.gov (United States)

    Marti, Merce; Montserrat, Núria; Pardo, Cristina; Mulero, Lola; Miquel-Serra, Laia; Rodrigues, Alexandre Miguel Cavaco; Andrés Vaquero, José; Kuebler, Bernd; Morera, Cristina; Barrero, María José; Izpisua Belmonte, Juan Carlos

    2013-11-15

    Adult muscle stem cells and their committed myogenic precursors, commonly referred to as the satellite cell population, are involved in both muscle growth after birth and regeneration after damage. It has been previously proposed that, under these circumstances, satellite cells first become activated, divide and differentiate, and only later fuse to the existing myofiber through M-cadherin-mediated intercellular interactions. Our data show that satellite cells fuse with the myofiber concomitantly to cell division, and only when the nuclei of the daughter cells are inside the myofiber, do they complete the process of differentiation. Here we demonstrate that M-cadherin plays an important role in cell-to-cell recognition and fusion, and is crucial for cell division activation. Treatment of satellite cells with M-cadherin in vitro stimulates cell division, whereas addition of anti-M-cadherin antibodies reduces the cell division rate. Our results suggest an alternative model for the contribution of satellite cells to muscle development, which might be useful in understanding muscle regeneration, as well as muscle-related dystrophies.

  15. Connecting the dots of the bacterial cell cycle: Coordinating chromosome replication and segregation with cell division.

    Science.gov (United States)

    Hajduk, Isabella V; Rodrigues, Christopher D A; Harry, Elizabeth J

    2016-05-01

    Proper division site selection is crucial for the survival of all organisms. What still eludes us is how bacteria position their division site with high precision, and in tight coordination with chromosome replication and segregation. Until recently, the general belief, at least in the model organisms Bacillus subtilis and Escherichia coli, was that spatial regulation of division comes about by the combined negative regulatory mechanisms of the Min system and nucleoid occlusion. However, as we review here, these two systems cannot be solely responsible for division site selection and we highlight additional regulatory mechanisms that are at play. In this review, we put forward evidence of how chromosome replication and segregation may have direct links with cell division in these bacteria and the benefit of recent advances in chromosome conformation capture techniques in providing important information about how these three processes mechanistically work together to achieve accurate generation of progenitor cells.

  16. 2008 Florida Division of Emergency Management (FDEM) Lidar Project: Pasco County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set is one component of a digital terrain model (DTM) for the Florida Division of Emergency Management's (FDEM) Project Management and Technical Services...

  17. About the Atlantic Ecology Division (AED) of EPA's National Health and Environmental Effects Research Laboratory

    Science.gov (United States)

    The Atlantic Ecology Division (AED), conducts innovative research and predictive modeling to assess and forecast the risks of anthropogenic stressors to near coastal waters and their watersheds, to develop tools to support resilient watersheds.

  18. Predicting division plane position and orientation.

    Science.gov (United States)

    Minc, Nicolas; Piel, Matthieu

    2012-04-01

    Predicting cellular behavior is a major challenge in cell and developmental biology. Since the late nineteenth century, empirical rules have been formulated to predict the position and orientation of mitotic cleavage planes in plant and animal cells. Here, we review the history of division plane orientation rules and discuss recent experimental and theoretical studies that refine these rules and provide mechanistic insights into how division can be predicted. We describe why some of these rules may better apply to certain cell types and developmental contexts and discuss how they could be integrated in the future to allow the prediction of division positioning in tissues.

  19. Earth Sciences Division collected abstracts: 1979

    Energy Technology Data Exchange (ETDEWEB)

    Henry, A.L.; Schwartz, L.L.

    1980-04-30

    This report is a compilation of abstracts of papers, internal reports, and talks presented during 1979 at national and international meetings by members of the Earth Sciences Division, Lawrence Livermore Laboratory. The arrangement is alphabetical (by author). For a given report, a bibliographic reference appears under the name of each coauthor, but the abstract iself is given only under the name of the first author or the first Earth Sciences Division author. A topical index at the end of the report provides useful cross references, while indicating major areas of research interest in the Earth Sciences Division.

  20. Chemical Sciences Division annual report 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    The division is one of ten LBL research divisions. It is composed of individual research groups organized into 5 scientific areas: chemical physics, inorganic/organometallic chemistry, actinide chemistry, atomic physics, and chemical engineering. Studies include structure and reactivity of critical reaction intermediates, transients and dynamics of elementary chemical reactions, and heterogeneous and homogeneous catalysis. Work for others included studies of superconducting properties of high-{Tc} oxides. In FY 1994, the division neared completion of two end-stations and a beamline for the Advanced Light Source, which will be used for combustion and other studies. This document presents summaries of the studies.

  1. Biology and Medicine Division: Annual report 1986

    Energy Technology Data Exchange (ETDEWEB)

    1987-04-01

    The Biology and Medicine Division continues to make important contributions in scientific areas in which it has a long-established leadership role. For 50 years the Division has pioneered in the application of radioisotopes and charged particles to biology and medicine. There is a growing emphasis on cellular and molecular applications in the work of all the Division's research groups. The powerful tools of genetic engineering, the use of recombinant products, the analytical application of DNA probes, and the use of restriction fragment length polymorphic DNA are described and proposed for increasing use in the future.

  2. Chemical and Laser Sciences Division annual report 1989

    Energy Technology Data Exchange (ETDEWEB)

    Haines, N. (ed.)

    1990-06-01

    The Chemical and Laser Sciences Division Annual Report includes articles describing representative research and development activities within the Division, as well as major programs to which the Division makes significant contributions.

  3. Atmospheric sciences division. Annual report, fiscal year 1981

    Energy Technology Data Exchange (ETDEWEB)

    Raynor, G. S. [ed.

    1981-12-01

    The research activities of the Atmospheric Sciences Division of the Department of Energy and Environment for FY 1981 are presented. Facilities and major items of equipment are described. Research programs are summarized in three categories, modeling, field and laboratory experiments and data management and analysis. Each program is also described individually with title, principal investigator, sponsor and funding levels for FY 1981 and FY 1982. Future plans are summarized. Publications for FY 1981 are listed with abstracts. A list of personnel is included.

  4. An introduction to orthogonal frequency-division multiplexing

    OpenAIRE

    Edfors, Ove; Sandell, Magnus; van de Beek, Jan-Jaap; Landström, Daniel; Sjöberg, Frank

    1996-01-01

    This report is an introduction to orthogonal frequency-division multiplexing (OFDM). The focus is on signal processing areas pursued by our research group at Luleå University of Technology. We present an historical background and some frequently used system models. Typical areas of applications are also described, both wireless and wired. In addition to the general overview, the addressed areas include synchronization, channel estimation and channel coding. Both time and frequency synchroniza...

  5. DNR Division of Enforcement Officer Patrol Areas

    Data.gov (United States)

    Minnesota Department of Natural Resources — This theme shows the DNR Division of Enforcement Office Patrol Areas as of January 1, 2003. Patrol areas were defined and verified by Patrol Officers during the fall...

  6. Spatial Divisions and Fertility in India

    Directory of Open Access Journals (Sweden)

    Vijayan Pillai

    2012-01-01

    Full Text Available The Indian subcontinent can be divided into four geographical divisions. In this paper, we characterize three of the four divisions; the Northern Plains, the Deccan Plateau, and the Northern Mountains or the Himalayan as regions with dissimilar climatic and physical resources. It is argued that human adaptations to these variations would be varied by differences in social organization of production and consumption resulting in differences in fertility differences across the three divisions. We found significant differences in the median age at motherhood as well as in the total family size. The effects of the three selected fertility determinants, age at marriage, years of woman's education, and level of child loss on family size also varied significantly across the three divisions. There is considerable homogeneity with respect to fertility levels within the zones considered in this study.

  7. About DCP | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) is the primary unit of the National Cancer Institute devoted to cancer prevention research. DCP provides funding and administrative support to clinical and laboratory researchers, community and multidisciplinary teams, and collaborative scientific networks. |

  8. Civil Remedies Division Administrative Law Judge Decisions

    Data.gov (United States)

    U.S. Department of Health & Human Services — Decisions issued by Administrative Law Judges of the Departmental Appeals Board's Civil Remedies Division concerning fraud and abuse determinations by the Office of...

  9. Chemical Sciences Division: Annual report 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    The Chemical Sciences Division (CSD) is one of twelve research Divisions of the Lawrence Berkeley Laboratory, a Department of Energy National Laboratory. The CSD is composed of individual groups and research programs that are organized into five scientific areas: Chemical Physics, Inorganic/Organometallic Chemistry, Actinide Chemistry, Atomic Physics, and Physical Chemistry. This report describes progress by the CSD for 1992. Also included are remarks by the Division Director, a description of work for others (United States Office of Naval Research), and appendices of the Division personnel and an index of investigators. Research reports are grouped as Fundamental Interactions (Photochemical and Radiation Sciences, Chemical Physics, Atomic Physics) or Processes and Techniques (Chemical Energy, Heavy-Element Chemistry, and Chemical Engineering Sciences).

  10. Overlapped frequency-time division multiplexing

    Institute of Scientific and Technical Information of China (English)

    JIANG Hui; LI Dao-ben

    2009-01-01

    A technique named overlapped frequency-time division multiplexing (OVFTDM)) is proposed in this article. The technique is derived from Nyquist system and frequency-time division multiplexing system. When the signals are compactly overlapped without the orthogonality in time domain, the technique is named overlapped time division multiplexing (OVTDM), whereas when signals are compactly overlapped without the orthogonality in frequency domain, the technique is called overlapped frequency division multiplexing (OVFDM). To further improve spectral efficiency, the OVFTDM in which signals are overlapped both in frequency domain and in time domain is explored. OVFTDM does not depend on orthogonality whatever in time domain or in frequency domain like Nyquist system or OFDM system, but on the convolutional constraint relationship among signals. Therefore, not only the spectral efficiency but also the reliability is improved. The simulations verify the validity of this theory.

  11. Environmental Research Division's Data Access Program (ERDDAP)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — ERDDAP (the Environmental Research Division's Data Access Program) is a data server that gives you a simple, consistent way to download subsets of scientific...

  12. [Diagnosticum of abnormalities of plant meiotic division].

    Science.gov (United States)

    Shamina, N V

    2006-01-01

    Abnormalities of plant meiotic division leading to abnormal meiotic products are summarized schematically in the paper. Causes of formation of monads, abnormal diads, triads, pentads, polyads, etc. have been observed in meiosis with both successive and simultaneous cytokinesis.

  13. Earth Sciences Division, collected abstracts, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Taasevigen, D.K.; Henry, A.L.; Madsen, S.K.

    1979-03-30

    Abstracts of papers, internal reports, and talks presented during 1978 at national and international meetings by members of the Earth Sciences Division of the Lawrence Livermore Laboratory are compiled. The arrangement is alphabetical (by author). For any given report, a bibliographic reference appears under the name of each coauthor. A topical index at the end provides useful cross references, while indicating major areas of research interest in the Earth Sciences Division.

  14. Weapons Experiments Division Explosives Operations Overview

    Energy Technology Data Exchange (ETDEWEB)

    Laintz, Kenneth E. [Los Alamos National Laboratory

    2012-06-19

    Presentation covers WX Division programmatic operations with a focus on JOWOG-9 interests. A brief look at DARHT is followed by a high level overview of explosives research activities currently being conducted within in the experimental groups of WX-Division. Presentation covers more emphasis of activities and facilities at TA-9 as these efforts have been more traditionally aligned with ongoing collaborative explosive exchanges covered under JOWOG-9.

  15. Nuclear Science Division: 1993 Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Myers, W.D. [ed.

    1994-06-01

    This report describes the activities of the Nuclear Science Division for the 1993 calendar year. This was another significant year in the history of the Division with many interesting and important accomplishments. Activities for the following programs are covered here: (1) nuclear structure and reactions program; (2) the Institute for Nuclear and Particle Astrophysics; (3) relativistic nuclear collisions program; (4) nuclear theory program; (5) nuclear data evaluation program, isotope project; and (6) 88-inch cyclotron operations.

  16. Stationary infinitely divisible processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.

    Several recent strands of work has led to the consideration of various types of continuous time stationary and infinitely divisible processes. A review of these types, with some new results, is presented.......Several recent strands of work has led to the consideration of various types of continuous time stationary and infinitely divisible processes. A review of these types, with some new results, is presented....

  17. Earth Sciences Division annual report 1989

    Energy Technology Data Exchange (ETDEWEB)

    1990-06-01

    This Annual Report presents summaries of selected representative research activities from Lawrence Berkeley Laboratory grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrology, Geology and Geochemistry, and Geophysics and Geomechanics. We are proud to be able to bring you this report, which we hope will convey not only a description of the Division's scientific activities but also a sense of the enthusiasm and excitement present today in the Earth Sciences.

  18. Medical Sciences Division report for 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    This year`s Medical Sciences Division (MSD) Report is organized to show how programs in our division contribute to the core competencies of Oak Ridge Institute for Science and Education (ORISE). ORISE`s core competencies in education and training, environmental and safety evaluation and analysis, occupational and environmental health, and enabling research support the overall mission of the US Department of Energy (DOE).

  19. On K sub 2 of division algebras

    CERN Document Server

    Guo Xue Jun; Qin Hou Rong

    2003-01-01

    In this paper, it is proved that if F is a global field or a local field, then every element of K sub 2 D is generated by symbols of form left brace a, b right brace with an element of F*, b is an element of D*, where D is a central division algebra over F. The tame kernel and wild kernel of central division algebra over F are expressed explicitly.

  20. Weapons Experiments Division Explosives Operations Overview

    Energy Technology Data Exchange (ETDEWEB)

    Laintz, Kenneth E. [Los Alamos National Laboratory

    2012-06-19

    Presentation covers WX Division programmatic operations with a focus on JOWOG-9 interests. A brief look at DARHT is followed by a high level overview of explosives research activities currently being conducted within in the experimental groups of WX-Division. Presentation covers more emphasis of activities and facilities at TA-9 as these efforts have been more traditionally aligned with ongoing collaborative explosive exchanges covered under JOWOG-9.

  1. Earth Sciences Division collected abstracts: 1980

    Energy Technology Data Exchange (ETDEWEB)

    Henry, A.L.; Hornady, B.F. (eds.)

    1981-10-15

    This report is a compilation of abstracts of papers, reports, and talks presented during 1980 at national and international meetings by members of the Earth Sciences Division, Lawrence Livermore National Laboratory. The arrangement is alphabetical (by author). For a given report, a bibliographic reference appears under the name of each coauthor, but the abstract itself is given only under the name of the first author (indicated in capital letters) or the first Earth Sciences Division author.

  2. Divisibility properties for C*-algebras

    DEFF Research Database (Denmark)

    Robert, Leonel; Rørdam, Mikael

    2013-01-01

    We consider three notions of divisibility in the Cuntz semigroup of a C*-algebra, and show how they reflect properties of the C*-algebra. We develop methods to construct (simple and non-simple) C*-algebras with specific divisibility behaviour. As a byproduct of our investigations, we show...... that there exists a sequence (An) of simple unital infinite dimensional C*-algebras such that the product ∏n=1∞ An has a character....

  3. Polarity in plant asymmetric cell division: Division orientation and cell fate differentiation

    OpenAIRE

    Shao, Wanchen; Dong, Juan

    2016-01-01

    Asymmetric cell division (ACD) is universally required for the development of multicellular organisms. Unlike animal cells, plant cells have a rigid cellulosic extracellular matrix, the cell wall, which provides physical support and forms communication routes. This fundamental difference leads to some unique mechanisms in plants for generating asymmetries during cell division. However, plants also utilize intrinsically polarized proteins to regulate asymmetric signaling and cell division, a s...

  4. Asymmetric cell division in polyploid giant cancer cells and low eukaryotic cells.

    Science.gov (United States)

    Zhang, Dan; Wang, Yijia; Zhang, Shiwu

    2014-01-01

    Asymmetric cell division is critical for generating cell diversity in low eukaryotic organisms. We previously have reported that polyploid giant cancer cells (PGCCs) induced by cobalt chloride demonstrate the ability to use an evolutionarily conserved process for renewal and fast reproduction, which is normally confined to simpler organisms. The budding yeast, Saccharomyces cerevisiae, which reproduces by asymmetric cell division, has long been a model for asymmetric cell division studies. PGCCs produce daughter cells asymmetrically in a manner similar to yeast, in that both use budding for cell polarization and cytokinesis. Here, we review the results of recent studies and discuss the similarities in the budding process between yeast and PGCCs.

  5. Bacterial cell division as a target for new antibiotics.

    Science.gov (United States)

    Sass, Peter; Brötz-Oesterhelt, Heike

    2013-10-01

    Bacterial resistance to currently applied antibiotics complicates the treatment of infections and demands the evaluation of new strategies to counteract multidrug-resistant bacteria. In recent years, the inhibition of the bacterial divisome, mainly by targeting the central cell division mediator FtsZ, has been recognized as a promising strategy for antibiotic attack. New antibiotics were shown to either interfere with the natural dynamics and functions of FtsZ during the cell cycle or to activate a bacterial protease to degrade FtsZ and thus bring about bacterial death in a suicidal manner. Their efficacy in animal models of infection together with resistance-breaking properties prove the potential of such drugs and validate the inhibition of bacterial cell division as an attractive approach for antibiotic intervention.

  6. The History of Metals and Ceramics Division

    Energy Technology Data Exchange (ETDEWEB)

    Craig, D.F.

    1999-01-01

    The division was formed in 1946 at the suggestion of Dr. Eugene P. Wigner to attack the problem of the distortion of graphite in the early reactors due to exposure to reactor neutrons, and the consequent radiation damage. It was called the Metallurgy Division and assembled the metallurgical and solid state physics activities of the time which were not directly related to nuclear weapons production. William A. Johnson, a Westinghouse employee, was named Division Director in 1946. In 1949 he was replaced by John H Frye Jr. when the Division consisted of 45 people. He was director during most of what is called the Reactor Project Years until 1973 and his retirement. During this period the Division evolved into three organizational areas: basic research, applied research in nuclear reactor materials, and reactor programs directly related to a specific reactor(s) being designed or built. The Division (Metals and Ceramics) consisted of 204 staff members in 1973 when James R. Weir, Jr., became Director. This was the period of the oil embargo, the formation of the Energy Research and Development Administration (ERDA) by combining the Atomic Energy Commission (AEC) with the Office of Coal Research, and subsequent formation of the Department of Energy (DOE). The diversification process continued when James O. Stiegler became Director in 1984, partially as a result of the pressure of legislation encouraging the national laboratories to work with U.S. industries on their problems. During that time the Division staff grew from 265 to 330. Douglas F. Craig became Director in 1992.

  7. Energy Technology Division research summary - 1999.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-31

    The Energy Technology Division provides materials and engineering technology support to a wide range of programs important to the US Department of Energy. As shown on the preceding page, the Division is organized into ten sections, five with concentrations in the materials area and five in engineering technology. Materials expertise includes fabrication, mechanical properties, corrosion, friction and lubrication, and irradiation effects. Our major engineering strengths are in heat and mass flow, sensors and instrumentation, nondestructive testing, transportation, and electromechanics and superconductivity applications. The Division Safety Coordinator, Environmental Compliance Officers, Quality Assurance Representative, Financial Administrator, and Communication Coordinator report directly to the Division Director. The Division Director is personally responsible for cultural diversity and is a member of the Laboratory-wide Cultural Diversity Advisory Committee. The Division's capabilities are generally applied to issues associated with energy production, transportation, utilization, or conservation, or with environmental issues linked to energy. As shown in the organization chart on the next page, the Division reports administratively to the Associate Laboratory Director (ALD) for Energy and Environmental Science and Technology (EEST) through the General Manager for Environmental and Industrial Technologies. While most of our programs are under the purview of the EEST ALD, we also have had programs funded under every one of the ALDs. Some of our research in superconductivity is funded through the Physical Research Program ALD. We also continue to work on a number of nuclear-energy-related programs under the ALD for Engineering Research. Detailed descriptions of our programs on a section-by-section basis are provided in the remainder of this book.

  8. 7 CFR 2.34 - Director, National Appeals Division.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Director, National Appeals Division. 2.34 Section 2.34... Heads § 2.34 Director, National Appeals Division. The Director, National Appeals Division, under the... officers and other employees as are necessary for the administration of the activities of the Division....

  9. Phenotypic plasticity and effects of selection on cell division symmetry in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Uttara N Lele

    Full Text Available Aging has been demonstrated in unicellular organisms and is presumably due to asymmetric distribution of damaged proteins and other components during cell division. Whether the asymmetry-induced aging is inevitable or an adaptive and adaptable response is debated. Although asymmetric division leads to aging and death of some cells, it increases the effective growth rate of the population as shown by theoretical and empirical studies. Mathematical models predict on the other hand, that if the cells divide symmetrically, cellular aging may be delayed or absent, growth rate will be reduced but growth yield will increase at optimum repair rates. Therefore in nutritionally dilute (oligotrophic environments, where growth yield may be more critical for survival, symmetric division may get selected. These predictions have not been empirically tested so far. We report here that Escherichia coli grown in oligotrophic environments had greater morphological and functional symmetry in cell division. Both phenotypic plasticity and genetic selection appeared to shape cell division time asymmetry but plasticity was lost on prolonged selection. Lineages selected on high nutrient concentration showed greater frequency of presumably old or dead cells. Further, there was a negative correlation between cell division time asymmetry and growth yield but there was no significant correlation between asymmetry and growth rate. The results suggest that cellular aging driven by asymmetric division may not be hardwired but shows substantial plasticity as well as evolvability in response to the nutritional environment.

  10. CyDiv, a conserved and novel filamentous Cyanobacteria cell division protein involved in septum localization.

    Directory of Open Access Journals (Sweden)

    Dinka eMandakovic

    2016-02-01

    Full Text Available Cell division in bacteria has been studied mostly in Escherichia coli and Bacillus subtilis, model organisms for Gram-negative and Gram-positive bacteria, respectively. However, cell division in filamentous cyanobacteria is poorly understood. Here, we identified a novel protein, named CyDiv (Cyanobacterial Division, encoded by the all2320 gene in Anabaena sp. PCC 7120. We show that CyDiv plays a key role during cell division. CyDiv has been previously described only as an exclusive and conserved hypothetical protein in filamentous cyanobacteria. Using polyclonal antibodies against CyDiv, we showed that it localizes at different positions depending on cell division timing: poles, septum, in both daughter cells, but also in only one of the daughter cells. The partial deletion of CyDiv gene generates partial defects in cell division, including severe membrane instability and anomalous septum localization during late division. The inability to complete knock out CyDiv strains suggests that it is an essential gene. In silico structural protein analyses and our experimental results suggest that CyDiv is an FtsB/DivIC-like protein, and could therefore, be part of an essential late divisome complex in Anabaena sp. PCC 7120.

  11. CyDiv, a Conserved and Novel Filamentous Cyanobacterial Cell Division Protein Involved in Septum Localization

    Science.gov (United States)

    Mandakovic, Dinka; Trigo, Carla; Andrade, Derly; Riquelme, Brenda; Gómez-Lillo, Gabriela; Soto-Liebe, Katia; Díez, Beatriz; Vásquez, Mónica

    2016-01-01

    Cell division in bacteria has been studied mostly in Escherichia coli and Bacillus subtilis, model organisms for Gram-negative and Gram-positive bacteria, respectively. However, cell division in filamentous cyanobacteria is poorly understood. Here, we identified a novel protein, named CyDiv (Cyanobacterial Division), encoded by the all2320 gene in Anabaena sp. PCC 7120. We show that CyDiv plays a key role during cell division. CyDiv has been previously described only as an exclusive and conserved hypothetical protein in filamentous cyanobacteria. Using polyclonal antibodies against CyDiv, we showed that it localizes at different positions depending on cell division timing: poles, septum, in both daughter cells, but also in only one of the daughter cells. The partial deletion of CyDiv gene generates partial defects in cell division, including severe membrane instability and anomalous septum localization during late division. The inability to complete knock out CyDiv strains suggests that it is an essential gene. In silico structural protein analyses and our experimental results suggest that CyDiv is an FtsB/DivIC-like protein, and could therefore, be part of an essential late divisome complex in Anabaena sp. PCC 7120. PMID:26903973

  12. Nuclear Chemistry Division annual report FY83

    Energy Technology Data Exchange (ETDEWEB)

    Struble, G. (ed.)

    1983-01-01

    The purpose of the annual reports of the Nuclear Chemistry Division is to provide a timely summary of research activities pursued by members of the Division during the preceding year. Throughout, details are kept to a minimum; readers desiring additional information are encouraged to read the referenced documents or contact the authors. The Introduction presents an overview of the Division's scientific and technical programs. Next is a section of short articles describing recent upgrades of the Division's major facilities, followed by sections highlighting scientific and technical advances. These are grouped under the following sections: nuclear explosives diagnostics; geochemistry and environmental sciences; safeguards technology and radiation effect; and supporting fundamental science. A brief overview introduces each section. Reports on research supported by a particular program are generally grouped together in the same section. The last section lists the scientific, administrative, and technical staff in the Division, along with visitors, consultants, and postdoctoral fellows. It also contains a list of recent publications and presentations. Some contributions to the annual report are classified and only their abstracts are included in this unclassified portion of the report (UCAR-10062-83/1); the full article appears in the classified portion (UCAR-10062-83/2).

  13. Control of apoptosis by asymmetric cell division.

    Directory of Open Access Journals (Sweden)

    Julia Hatzold

    2008-04-01

    Full Text Available Asymmetric cell division and apoptosis (programmed cell death are two fundamental processes that are important for the development and function of multicellular organisms. We have found that the processes of asymmetric cell division and apoptosis can be functionally linked. Specifically, we show that asymmetric cell division in the nematode Caenorhabditis elegans is mediated by a pathway involving three genes, dnj-11 MIDA1, ces-2 HLF, and ces-1 Snail, that directly control the enzymatic machinery responsible for apoptosis. Interestingly, the MIDA1-like protein GlsA of the alga Volvox carteri, as well as the Snail-related proteins Snail, Escargot, and Worniu of Drosophila melanogaster, have previously been implicated in asymmetric cell division. Therefore, C. elegans dnj-11 MIDA1, ces-2 HLF, and ces-1 Snail may be components of a pathway involved in asymmetric cell division that is conserved throughout the plant and animal kingdoms. Furthermore, based on our results, we propose that this pathway directly controls the apoptotic fate in C. elegans, and possibly other animals as well.

  14. Evolution of the chloroplast division machinery

    Institute of Scientific and Technical Information of China (English)

    Hongbo GAO; Fuli GAO

    2011-01-01

    Chloroplasts are photosynthetic organelles derived from endosymbiotic cyanobacteria during evolution.Dramatic changes occurred during the process of the formation and evolution of chloroplasts,including the large-scale gene transfer from chloroplast to nucleus.However,there are still many essential characters remaining.For the chloroplast division machinery,FtsZ proteins,Ftn2,SulA and part of the division site positioning system- MinD and MinE are still conserved.New or at least partially new proteins,such as FtsZ family proteins FtsZl and ARC3,ARC6H,ARC5,PDV1,PDV2 and MCD1,were introduced for the division of chloroplasts during evolution.Some bacterial cell division proteins,such as FtsA,MreB,Ftn6,FtsW and Ftsl,probably lost their function or were gradually lost.Thus,the chloroplast division machinery is a dynamically evolving structure with both conservation and innovation.

  15. Parkin suppresses Drp1-independent mitochondrial division.

    Science.gov (United States)

    Roy, Madhuparna; Itoh, Kie; Iijima, Miho; Sesaki, Hiromi

    2016-07-01

    The cycle of mitochondrial division and fusion disconnect and reconnect individual mitochondria in cells to remodel this energy-producing organelle. Although dynamin-related protein 1 (Drp1) plays a major role in mitochondrial division in cells, a reduced level of mitochondrial division still persists even in the absence of Drp1. It is unknown how much Drp1-mediated mitochondrial division accounts for the connectivity of mitochondria. The role of a Parkinson's disease-associated protein-parkin, which biochemically and genetically interacts with Drp1-in mitochondrial connectivity also remains poorly understood. Here, we quantified the number and connectivity of mitochondria using mitochondria-targeted photoactivatable GFP in cells. We show that the loss of Drp1 increases the connectivity of mitochondria by 15-fold in mouse embryonic fibroblasts (MEFs). While a single loss of parkin does not affect the connectivity of mitochondria, the connectivity of mitochondria significantly decreased compared with a single loss of Drp1 when parkin was lost in the absence of Drp1. Furthermore, the loss of parkin decreased the frequency of depolarization of the mitochondrial inner membrane that is caused by increased mitochondrial connectivity in Drp1-knockout MEFs. Therefore, our data suggest that parkin negatively regulates Drp1-indendent mitochondrial division.

  16. Arabidopsis  SABRE and CLASP interact to stabilize cell division plane orientation and planar polarity

    OpenAIRE

    2013-01-01

    The orientation of cell division and the coordination of cell polarity within the plane of the tissue layer (planar polarity) contribute to shape diverse multicellular organisms. The root of Arabidopsis thaliana displays regularly oriented cell divisions, cell elongation and planar polarity providing a plant model system to study these processes. Here we report that the SABRE protein, which shares similarity with proteins of unknown function throughout eukaryotes, has important roles in orien...

  17. Condensation of FtsZ filaments can drive bacterial cell division.

    Science.gov (United States)

    Lan, Ganhui; Daniels, Brian R; Dobrowsky, Terrence M; Wirtz, Denis; Sun, Sean X

    2009-01-06

    Forces are important in biological systems for accomplishing key cell functions, such as motility, organelle transport, and cell division. Currently, known force generation mechanisms typically involve motor proteins. In bacterial cells, no known motor proteins are involved in cell division. Instead, a division ring (Z-ring) consists of mostly FtsZ, FtsA, and ZipA is used to exerting a contractile force. The mechanism of force generation in bacterial cell division is unknown. Using computational modeling, we show that Z-ring formation results from the colocalization of FtsZ and FtsA mediated by the favorable alignment of FtsZ polymers. The model predicts that the Z-ring undergoes a condensation transition from a low-density state to a high-density state and generates a sufficient contractile force to achieve division. FtsZ GTP hydrolysis facilitates monomer turnover during the condensation transition, but does not directly generate forces. In vivo fluorescence measurements show that FtsZ density increases during division, in accord with model results. The mechanism is akin to van der Waals picture of gas-liquid condensation, and shows that organisms can exploit microphase transitions to generate mechanical forces.

  18. Cell Division and Evolution of Biological Tissues

    Science.gov (United States)

    Rivier, Nicolas; Arcenegui-Siemens, Xavier; Schliecker, Gudrun

    A tissue is a geometrical, space-filling, random cellular network; it remains in this steady state while individual cells divide. Cell division (fragmentation) is a local, elementary topological transformation which establishes statistical equilibrium of the structure. Statistical equilibrium is characterized by observable relations (Lewis, Aboav) between cell shapes, sizes and those of their neighbours, obtained through maximum entropy and topological correlation extending to nearest neighbours only, i.e. maximal randomness. For a two-dimensional tissue (epithelium), the distribution of cell shapes and that of mother and daughter cells can be obtained from elementary geometrical and physical arguments, except for an exponential factor favouring division of larger cells, and exponential and combinatorial factors encouraging a most symmetric division. The resulting distributions are very narrow, and stationarity severely restricts the range of an adjustable structural parameter

  19. Chemical Technology Division annual technical report, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    CMT is a diverse technical organization with principal emphases in environmental management and development of advanced energy sources. It conducts R&D in 3 general areas: development of advanced power sources for stationary and transportation applications and for consumer electronics, management of high-level and low-level nuclear wastes and hazardous wastes, and electrometallurgical treatment of spent nuclear fuel. The Division also performs basic research in catalytic chemistry involving molecular energy resources, mechanisms of ion transport in lithium battery electrolytes, materials chemistry of electrified interfaces and molecular sieves, and the theory of materials properties. It also operates the Analytical Chemistry Laboratory, which conducts research in analytical chemistry and provides analytical services for programs at ANL and other organizations. Technical highlights of the Division`s activities during 1996 are presented.

  20. The Astrophysics Science Division Annual Report 2008

    Science.gov (United States)

    Oegerle, William; Reddy, Francis; Tyler, Pat

    2009-01-01

    The Astrophysics Science Division (ASD) at Goddard Space Flight Center (GSFC) is one of the largest and most diverse astrophysical organizations in the world, with activities spanning a broad range of topics in theory, observation, and mission and technology development. Scientific research is carried out over the entire electromagnetic spectrum from gamma rays to radio wavelengths as well as particle physics and gravitational radiation. Members of ASD also provide the scientific operations for three orbiting astrophysics missions WMAP, RXTE, and Swift, as well as the Science Support Center for the Fermi Gamma-ray Space Telescope. A number of key technologies for future missions are also under development in the Division, including X-ray mirrors, and new detectors operating at gamma-ray, X-ray, ultraviolet, infrared, and radio wavelengths. This report includes the Division's activities during 2008.

  1. Family division in China's transitional economy.

    Science.gov (United States)

    Chen, Feinian

    2009-03-01

    Using a longitudinal data-set (the China Health and Nutrition Survey) we explored the effect of various economic factors, including household wealth, employment sector, and involvement in a household business on the division of extended families in China's transitional economy. Results from event history analyses suggest that these economic factors act as either a dividing or a unifying force on the extended family. Household wealth reduces the risk of family division, but the effect is weaker for families in which parents have upper secondary education. In addition, an extended family is more likely to divide when married children work in the state sector. Further, the probability of family division is higher in families where daughters-in-law work in the state sector than in those with sons in this sector. Finally, involvement in a household business for married children increases family stability.

  2. Biology Division progress report, October 1, 1991--September 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, F.C.; Cook, J.S.

    1993-10-01

    This Progress Report summarizes the research endeavors of the Biology Division of the Oak Ridge National Laboratory during the period October 1, 1991, through September 30, 1993. The report is structured to provide descriptions of current activities and accomplishments in each of the Division`s major organizational units. Lists of information to convey the entire scope of the Division`s activities are compiled at the end of the report.

  3. Facial-Attractiveness Choices Are Predicted by Divisive Normalization.

    Science.gov (United States)

    Furl, Nicholas

    2016-10-01

    Do people appear more attractive or less attractive depending on the company they keep? A divisive-normalization account-in which representation of stimulus intensity is normalized (divided) by concurrent stimulus intensities-predicts that choice preferences among options increase with the range of option values. In the first experiment reported here, I manipulated the range of attractiveness of the faces presented on each trial by varying the attractiveness of an undesirable distractor face that was presented simultaneously with two attractive targets, and participants were asked to choose the most attractive face. I used normalization models to predict the context dependence of preferences regarding facial attractiveness. The more unattractive the distractor, the more one of the targets was preferred over the other target, which suggests that divisive normalization (a potential canonical computation in the brain) influences social evaluations. I obtained the same result when I manipulated faces' averageness and participants chose the most average face. This finding suggests that divisive normalization is not restricted to value-based decisions (e.g., attractiveness). This new application to social evaluation of normalization, a classic theory, opens possibilities for predicting social decisions in naturalistic contexts such as advertising or dating.

  4. Parkin suppresses Drp1-independent mitochondrial division

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Madhuparna, E-mail: mroy17@jhmi.edu; Itoh, Kie, E-mail: kito5@jhmi.edu; Iijima, Miho, E-mail: miijima@jhmi.edu; Sesaki, Hiromi, E-mail: hsesaki@jhmi.edu

    2016-07-01

    The cycle of mitochondrial division and fusion disconnect and reconnect individual mitochondria in cells to remodel this energy-producing organelle. Although dynamin-related protein 1 (Drp1) plays a major role in mitochondrial division in cells, a reduced level of mitochondrial division still persists even in the absence of Drp1. It is unknown how much Drp1-mediated mitochondrial division accounts for the connectivity of mitochondria. The role of a Parkinson’s disease-associated protein—parkin, which biochemically and genetically interacts with Drp1—in mitochondrial connectivity also remains poorly understood. Here, we quantified the number and connectivity of mitochondria using mitochondria-targeted photoactivatable GFP in cells. We show that the loss of Drp1 increases the connectivity of mitochondria by 15-fold in mouse embryonic fibroblasts (MEFs). While a single loss of parkin does not affect the connectivity of mitochondria, the connectivity of mitochondria significantly decreased compared with a single loss of Drp1 when parkin was lost in the absence of Drp1. Furthermore, the loss of parkin decreased the frequency of depolarization of the mitochondrial inner membrane that is caused by increased mitochondrial connectivity in Drp1-knockout MEFs. Therefore, our data suggest that parkin negatively regulates Drp1-indendent mitochondrial division. -- Highlights: •A Drp1-mediated mechanism accounts for ∼95% of mitochondrial division. •Parkin controls the connectivity of mitochondria via a mechanism that is independent of Drp1. •In the absence of Drp1, connected mitochondria transiently depolarize. •The transient depolarization is independent of calcium signaling and uncoupling protein 2.

  5. Life Sciences Division Spaceflight Hardware

    Science.gov (United States)

    Yost, B.

    1999-01-01

    The Ames Research Center (ARC) is responsible for the development, integration, and operation of non-human life sciences payloads in support of NASA's Gravitational Biology and Ecology (GB&E) program. To help stimulate discussion and interest in the development and application of novel technologies for incorporation within non-human life sciences experiment systems, three hardware system models will be displayed with associated graphics/text explanations. First, an Animal Enclosure Model (AEM) will be shown to communicate the nature and types of constraints physiological researchers must deal with during manned space flight experiments using rodent specimens. Second, a model of the Modular Cultivation System (MCS) under development by ESA will be presented to highlight technologies that may benefit cell-based research, including advanced imaging technologies. Finally, subsystems of the Cell Culture Unit (CCU) in development by ARC will also be shown. A discussion will be provided on candidate technology requirements in the areas of specimen environmental control, biotelemetry, telescience and telerobotics, and in situ analytical techniques and imaging. In addition, an overview of the Center for Gravitational Biology Research facilities will be provided.

  6. Division XII: Commission 6: Astronomical Telegrams

    Science.gov (United States)

    Samus, N. N.; Yamaoka, H.; Gilmore, A. C.; Aksnes, K.; Green, D. W. E.; Marsden, B. G.; Nakano, S.; Lara, Martin; Pitjeva, Elena V.; Sphar, T.; Ticha, J.; Williams, G.

    2015-08-01

    IAU Commission 6 ``Astronomical Telegrams'' had a single business meeting during the Beijing General Assembly of the IAU. It took place on Friday, August 24, 2012. The meeting was attended by five C6 members (N. N. Samus; D. W. E. Green; S. Nakano; J. Ticha; and H. Yamaoka). Also present was Prof. F. Genova as a representative of the IAU Division B. She told the audience about the current restructuring of IAU Commissions and Divisions and consequences for the future of C6.

  7. Quantum internet using code division multiple access

    Science.gov (United States)

    Zhang, Jing; Liu, Yu-xi; Özdemir, Şahin Kaya; Wu, Re-Bing; Gao, Feifei; Wang, Xiang-Bin; Yang, Lan; Nori, Franco

    2013-01-01

    A crucial open problem inS large-scale quantum networks is how to efficiently transmit quantum data among many pairs of users via a common data-transmission medium. We propose a solution by developing a quantum code division multiple access (q-CDMA) approach in which quantum information is chaotically encoded to spread its spectral content, and then decoded via chaos synchronization to separate different sender-receiver pairs. In comparison to other existing approaches, such as frequency division multiple access (FDMA), the proposed q-CDMA can greatly increase the information rates per channel used, especially for very noisy quantum channels. PMID:23860488

  8. Life Sciences Division annual report, 1988

    Energy Technology Data Exchange (ETDEWEB)

    Marrone, B.L.; Cram, L.S. (comps.)

    1989-04-01

    This report summarizes the research and development activities of Los Alamos National Laboratory's Life Sciences Division for the calendar year 1988. Technical reports related to the current status of projects are presented in sufficient detail to permit the informed reader to assess their scope and significance. Summaries useful to the casual reader desiring general information have been prepared by the Group Leaders and appear in each group overview. Investigators on the staff of the Life Sciences Division will be pleased to provide further information.

  9. Dynamic self-organisation of haematopoiesis and (a)symmetric cell division.

    Science.gov (United States)

    Måløy, Marthe; Måløy, Frode; Jakobsen, Per; Olav Brandsdal, Bjørn

    2017-02-07

    A model of haematopoiesis that links self-organisation with symmetric and asymmetric cell division is presented in this paper. It is assumed that all cell divisions are completely random events, and that the daughter cells resulting from symmetric and asymmetric stem cell divisions are, in general, phenotypically identical, and still, the haematopoietic system has the flexibility to self-renew, produce mature cells by differentiation, and regenerate undifferentiated and differentiated cells when necessary, due to self-organisation. As far as we know, no previous model implements symmetric and asymmetric division as the result of self-organisation. The model presented in this paper is inspired by experiments on the Drosophila germline stem cell, which imply that under normal conditions, the stem cells typically divide asymmetrically, whereas during regeneration, the rate of symmetric division increases. Moreover, the model can reproduce several of the results from experiments on female Safari cats. In particular, the model can explain why significant fluctuation in the phenotypes of haematopoietic cells was observed in some cats, when the haematopoietic system had reached normal population level after regeneration. To our knowledge, no previous model of haematopoiesis in Safari cats has captured this phenomenon. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Optimal architecture of differentiation cascades with asymmetric and symmetric stem cell division.

    Science.gov (United States)

    Sánchez-Taltavull, Daniel

    2016-10-21

    The role of symmetric division in stem cell biology is ambiguous. It is necessary after injuries, but if symmetric divisions occur too often, the appearance of tumours is more likely. To explore the role of symmetric and asymmetric division in cell populations, we propose a mathematical model of competition of populations, in which the stem cell expansion is controlled by fully differentiated cells. We show that there is an optimal fraction of symmetric stem cell division, which maximises the long-term survival probability of the organism. Moreover, we show the optimal number of stem cells in a tissue, and we show that number has to be small enough to reduce the probability of the appearance of advantageous malignant cells, and large enough to assure that the population will not be suppressed by stochastic fluctuations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Division Models of Profit in Three-Echelon Reverse Supply Chain Cooperation Based on Nash Models%基于Nash谈判的三级逆向供应链合作利益分配模型

    Institute of Scientific and Technical Information of China (English)

    贡文伟; 葛翠翠; 陈敬贤; 潘建国

    2011-01-01

    It needs effort of everyone who takes part in the RSC and reasonable distribution of profits to make sure the RSC operate smoothly. In this paper we aim at a three-echelon RSC system which is composed of one manufacturer, one retailer and third party logistics provider to research the cooperation of RSC with Stakelberg game theory model and consideration the weights of all parties involved in the status of the RSC to allocate the benefits twice by using Nash bargaining models. The results show that, RSC cooperation and reasonable distribution of benefits of cooperation could improve the level of return of the parties, and their income level is proportional to the position in the chain. Also they benefit the custom and improve resource' s utilization. It possesses high practical significance.%逆向供应链的顺利实施需要各方的共同努力以及合理的利益分配,针对由制造商、零售商和第三方物流服务商组成的三级逆向供应链系统,应用Stakelberg博弈模型研究三级逆向供应链的合作问题,并考虑合作各方参与逆向供应链的地位权重,运用Nash谈判模型对总体利益进行两次分配.研究结果表明,逆向供应链的合作及合理的利益分配可提高合作各方的收益水平,并且收益水平与其在链中的地位成正比,同时还可以惠及产品的消费者,提高资源利用水平,具有较高的实践意义.

  12. Trial NCT01950403 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  13. Trial NCT01141231 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  14. Trial NCT02237183 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  15. Trial NCT01382082 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  16. Trial NCT02273362 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  17. Meetings and Events | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  18. Trial NCT02112188 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  19. Trial NCT01824836 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  20. Trial NCT01968798 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  1. Trial NCT01849250 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  2. Trial NCT02116530 | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  3. Clinical Trials Management | Division of Cancer Prevention

    Science.gov (United States)

    Information for researchers about developing, reporting, and managing NCI-funded cancer prevention clinical trials. Protocol Information Office The central clearinghouse for clinical trials management within the Division of Cancer Prevention.Read more about the Protocol Information Office. | Information for researchers about developing, reporting, and managing NCI-funded cancer prevention clinical trials.

  4. On-chip mode division multiplexing technologies

    DEFF Research Database (Denmark)

    Ding, Yunhong; Frellsen, Louise Floor; Guan, Xiaowei

    2016-01-01

    using one-dimensional (1D) photonic crystal silicon waveguides. We furthermore use the fabricated devices to demonstrate on-chip point-to-point mode division multiplexing transmission, and all-optical signal processing by mode-selective wavelength conversion. Finally, we report an efficient silicon...

  5. Physics Division activities report, 1986--1987

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    This report summarizes the research activities of the Physics Division for the years 1986 and 1987. Areas of research discussed in this paper are: research on e/sup +/e/sup /minus// interactions; research on p/bar p/ interactions; experiment at TRIUMF; double beta decay; high energy astrophysics; interdisciplinary research; and advanced technology development and the SSC.

  6. Problems on Divisibility of Binomial Coefficients

    Science.gov (United States)

    Osler, Thomas J.; Smoak, James

    2004-01-01

    Twelve unusual problems involving divisibility of the binomial coefficients are represented in this article. The problems are listed in "The Problems" section. All twelve problems have short solutions which are listed in "The Solutions" section. These problems could be assigned to students in any course in which the binomial theorem and Pascal's…

  7. Mathematical Induction, Difference Equations and Divisibility

    Science.gov (United States)

    McAndrew, Alasdair

    2009-01-01

    Many exercises in mathematical induction require the student to prove a divisibility property of a function of the integers. Such problems are generally presented as being independent of each other. However, many of these problems can be presented in terms of difference equations, and the theory of difference equations can be used to provide a…

  8. BIGAMOUS MARRIAGE AND THE DIVISION OF COMMON ...

    African Journals Online (AJOL)

    milkii

    married women in Ethiopia are in bigamous marriage, with nine percent .... The Southern Rhodesia Native Affairs Department Annual, Vol. 12, No.1 (1979), p. .... Marry: New Life for an Old Lifestyle, Memphis State University Law Review, Vol. ...... the effects of such property division on the life journey and stakeholders of the.

  9. Bacterial cell division proteins as antibiotic targets

    NARCIS (Netherlands)

    den Blaauwen, T.; Andreu, J.M.; Monasterio, O.

    2014-01-01

    Proteins involved in bacterial cell division often do not have a counterpart in eukaryotic cells and they are essential for the survival of the bacteria. The genetic accessibility of many bacterial species in combination with the Green Fluorescence Protein revolution to study localization of

  10. Cell division activity during apical hook development

    NARCIS (Netherlands)

    Raz, V.; Koornneef, M.

    2001-01-01

    Growth during plant development is predominantly governed by the combined activities of cell division and cell elongation. The relative contribution of both activities controls the growth of a tissue. A fast change in growth is exhibited at the apical hypocotyl of etiolated seedlings where cells

  11. 2008 Research Portfolio: Research & Development Division

    Science.gov (United States)

    Educational Testing Service, 2008

    2008-01-01

    This document describes the breadth of the research being conducted in 2008 by the Research and Development Division at Educational Testing Service (ETS). The research described falls into three large categories: (1) Research supported by the ETS research allocation; (2) Research funded by testing programs at ETS; and (3) Research funded by…

  12. Materials Sciences Division 1990 annual report

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    This report is the Materials Sciences Division's annual report. It contains abstracts describing materials research at the National Center for Electron Microscopy, and for research groups in metallurgy, solid-state physics, materials chemistry, electrochemical energy storage, electronic materials, surface science and catalysis, ceramic science, high tc superconductivity, polymers, composites, and high performance metals.

  13. Theoretical Division annual report, FY 1975. [LASL

    Energy Technology Data Exchange (ETDEWEB)

    Carruthers, P.A.

    1976-02-01

    This report presents an overview of the activities in the Theoretical Division and a summary of research highlights during FY 1975. It is intended to inform a wide audience about the theoretical work of the LASL and, therefore, contains introductory material which places recent advances in a broader context. The report is organized into two special interest reports: reactor safety research and the Advanced Research Committee, and 11 reports from the T-Division group leaders on the work of their respective groups. Main interests and responsibilities are outlined including the relationship of the group's work to the work of other T-Division groups and other divisions at the Laboratory. The description of research highlights for FY 1975 explains in a fairly simple, straightforward manner the major recent advances and their significance. Each group report is followed by a publication list for FY 1975 (330 references) and a list of talks given outside the Laboratory (140 references). 29 figures. (auth)

  14. 25 CFR 227.19 - Division orders.

    Science.gov (United States)

    2010-04-01

    ... INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF CERTAIN LANDS IN WIND RIVER INDIAN RESERVATION, WYOMING, FOR OIL AND GAS MINING Rents and Royalties § 227.19 Division orders. (a... it to the supervisor for his consideration. The right is reserved for the supervisor to cancel...

  15. Keypad Geometry and Divisibility of Numbers

    Science.gov (United States)

    Van Dyke, Frances; Keynes, Michael

    2010-01-01

    In this article, the authors show how students can form familiar geometric figures on the calculator keypad and generate numbers that are all divisible by a common number. Students are intrigued by the results and want to know "why it works". The activities can be presented and students given an extended amount of time to think about…

  16. Kara Smigel Croker | Division of Cancer Prevention

    Science.gov (United States)

    Kara Smigel Croker is the Communications Manager for the National Cancer Institute Division of Cancer Prevention. She coordinates and supports all aspects of communication, including media contacts, writing and editing of reports and responses, divisional websites, and social media. |

  17. Clinical Trials Node | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  18. Annalisa Gnoleba, MSA | Division of Cancer Prevention

    Science.gov (United States)

    Mrs. Annalisa Gnoleba is the Public Health Analyst for the Cancer Prevention Fellowship Program, Division of Cancer Prevention, National Cancer Institute. In this position, Mrs. Gnoleba serves as the analyst for developing and formulating short and long range public health program goals, objectives and policies. |

  19. Nutritional Science Staff | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

  20. Chemical Biodynamics Division. Annual report 1979

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    The Chemical Biodynamics Division of LBL continues to conduct basic research on the dynamics of living cells and on the interaction of radiant energy with organic matter. Many aspects of this basic research are related to problems of environmental and health effects of fossil fuel combustion, solar energy conversion and chemical/ viral carcinogenesis.

  1. Flexible frontiers for text division into rows

    Directory of Open Access Journals (Sweden)

    Dan L. Lacrămă

    2009-01-01

    Full Text Available This paper presents an original solution for flexible hand-written text division into rows. Unlike the standard procedure, the proposed method avoids the isolated characters extensions amputation and reduces the recognition error rate in the final stage.

  2. Cell division activity during apical hook development

    NARCIS (Netherlands)

    Raz, V.; Koornneef, M.

    2001-01-01

    Growth during plant development is predominantly governed by the combined activities of cell division and cell elongation. The relative contribution of both activities controls the growth of a tissue. A fast change in growth is exhibited at the apical hypocotyl of etiolated seedlings where cells gro

  3. Cell division in Corynebacterineae

    Directory of Open Access Journals (Sweden)

    Catriona eDonovan

    2014-04-01

    Full Text Available Bacterial cells must coordinate a number of events during the cell cycle. Spatio-temporal regulation of bacterial cytokinesis is indispensable for the production of viable, genetically identical offspring. In many rod-shaped bacteria, precise midcell assembly of the division machinery relies on inhibitory systems such as Min and Noc. In rod-shaped Actinobacteria, for example Corynebacterium glutamicum and Mycobacterium tuberculosis, the divisome assembles in the proximity of the midcell region, however more spatial flexibility is observed compared to Escherichia coli and Bacillus subtilis. Actinobacteria represent a group of bacteria that spatially regulate cytokinesis in the absence of recognizable Min and Noc homologs. The key cell division steps in E. coli and B. subtilis have been subject to intensive study and are well understood. In comparison, only a minimal set of positive and negative regulators of cytokinesis are known in Actinobacteria. Nonetheless, the timing of cytokinesis and the placement of the division septum is coordinated with growth as well as initiation of chromosome replication and segregation. We summarize here the current knowledge on cytokinesis and division site selection in the Actinobacteria suborder Corynebacterineae.

  4. Energy Technology Division research summary 1997.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-21

    The Energy Technology Division provides materials and engineering technology support to a wide range of programs important to the US Department of Energy. As shown on the preceding page, the Division is organized into ten sections, five with concentrations in the materials area and five in engineering technology. Materials expertise includes fabrication, mechanical properties, corrosion, friction and lubrication, and irradiation effects. Our major engineering strengths are in heat and mass flow, sensors and instrumentation, nondestructive testing, transportation, and electromechanics and superconductivity applications. The Division Safety Coordinator, Environmental Compliance Officers, Quality Assurance Representative, Financial Administrator, and Communication Coordinator report directly to the Division Director. The Division Director is personally responsible for cultural diversity and is a member of the Laboratory-wide Cultural Diversity Advisory Committee. The Division's capabilities are generally applied to issues associated with energy production, transportation, utilization or conservation, or with environmental issues linked to energy. As shown in the organization chart on the next page, the Division reports administratively to the Associate Laboratory Director (ALD) for Energy and Environmental Science and Technology (EEST) through the General Manager for Environmental and Industrial Technologies. While most of our programs are under the purview of the EEST ALD, we also have had programs funded under every one of the ALDs. Some of our research in superconductivity is funded through the Physical Research Program ALD. We also continue to work on a number of nuclear-energy-related programs under the ALD for Engineering Research. Detailed descriptions of our programs on a section-by-section basis are provided in the remainder of this book. This Overview highlights some major trends. Research related to the operational safety of commercial light water

  5. Year four pupils' understanding of division of whole numbers

    Science.gov (United States)

    Ibrahim, Faridah Mohamed; Pa, Nik Azis Nik

    2014-07-01

    Based on the theory of radical constructivism, this study investigated Year Four pupils' understandings of division by identifying their schemes of the division of whole numbers and how they used them in solving related problematic situations. Data incorporating both verbal and non-verbal behaviors were gathered from seven pupils based on the five clinical interview sessions involving imagining division, representing division, describing process and product of division, interpreting division statement, and solving division problem tasks. Four schemes that were identified are partitioning scheme, measuring scheme, repeated subtraction scheme, and inverse of multiplication scheme. Findings revealed that the measuring scheme was the dominant scheme for the division of whole numbers and the pupils only used the repeated and the inverse of multiplication schemes when they were asked to relate the subtraction or multiplication process with the division process. Further, the pupils were observed to use the long division algorithm in some situations, but there were indications that they used them with little understandings. It is suggested that more remains to be learnt about the nature of pupils' understanding of the division of whole numbers and how schemes of the division of whole numbers are formed and modified. Also, in order to provide appropriate guidance, mathematics teachers need to have some knowledge about pupils' available schemes of the division of whole numbers, no matter how primitive they might seem to the teachers.

  6. Formation of a cylindrical bridge in cell division

    Science.gov (United States)

    Citron, Daniel; Schmidt, Laura E.; Reichl, Elizabeth; Ren, Yixin; Robinson, Douglas; Zhang, Wendy W.

    2007-11-01

    In nature, the shape transition associated with the division of a mother cell into two daughter cells proceeds via a variety of routes. In the cylinder-thinning route, which has been observed in Dictyostelium and most animal cells, the mother cell first forms a broad bridge-like region, also known as a furrow, between two daughter cells. The furrow then rapidly evolves into a cylindrical bridge, which thins and eventually severs the mother cell into two. The fundamental mechanism underlying this division route is not understood. Recent experiments on Dictyostelium found that, while the cylinder-thinning route persists even when key actin cross-linking proteins are missing, it is disrupted by the removal of force-generating myosin-II proteins. Other measurements revealed that mutant cells lacking myosin-II have a much more uniform tension over the cell surface than wild-type cells. This suggests that tension variation may be important. Here we use a fluid model, previously shown to reproduce the thinning dynamics [Zhang & Robinson, PNAS 102, 7186 (2005)], to test this idea. Consistent with the experiments, the model shows that the cylinder formation process occurs regardless of the exact viscoelastic properties of the cell. In contrast to the experiments, a tension variation in the model hinders, rather then expedites, the cylinder formation.

  7. Tidal impacts on the subtidal flow division at the main bifurcation in the Yangtze River Delta

    Science.gov (United States)

    Zhang, Wei; Feng, Haochuan; Hoitink, A. J. F.; Zhu, Yuliang; Gong, Fei; Zheng, Jinhai

    2017-09-01

    Flow division at bifurcations in the Yangtze Estuary has received ample attention, since it may control the pathways of terrestrial sediments over downstream river branches including the 12.5 m Deepwater Navigation channel. While some efforts have been made to interpret flow division at the bifurcations of the Yangtze Estuary, little attention has been paid to the role of tides. Flow division at estuarine bifurcations is made complicated by tides that propagate from the outlet of the tidal channels into the delta. To quantify the tidal influence on the distribution of river discharge, and more generally, to understand the mechanisms governing the subtidal flow division at the tidally affected bifurcation in the Yangtze River Delta, a two-dimensional hydrodynamic model is employed. In this model, the landward boundary is chosen beyond the tidal limit, where the tidal motion has faded out entirely. The seaward boundary is chosen such that the river discharge does not influence the water level. Subtidal discharges are decomposed using the method of factor separation, to distinguish between the effects of tides, river discharge and river-tide interactions on the subtidal flow division. Results indicate that tides modify the river discharge distribution over distributary channels in the Yangtze River Delta, particularly in the dry season. A significant difference in the subtidal flow division during spring tide and neap tide shows that the tidally averaged flow division over the distributaries in the delta greatly depends on tidal amplitude. By varying the river discharge at the landward boundary and amplitudes and phases of the principal tidal constituents at the seaward boundary of the established model, the sensitivities of the subtidal flow division to the river discharge and tidal amplitude variation were investigated in detail. Generally, the tidal impacts on the subtidal flow division are around 12% to 22%, with river discharge varying from 30,000 m3s-1 to 20

  8. A theory of germinal center B cell selection, division, and exit.

    Science.gov (United States)

    Meyer-Hermann, Michael; Mohr, Elodie; Pelletier, Nadége; Zhang, Yang; Victora, Gabriel D; Toellner, Kai-Michael

    2012-07-26

    High-affinity antibodies are generated in germinal centers in a process involving mutation and selection of B cells. Information processing in germinal center reactions has been investigated in a number of recent experiments. These have revealed cell migration patterns, asymmetric cell divisions, and cell-cell interaction characteristics, used here to develop a theory of germinal center B cell selection, division, and exit (the LEDA model). According to this model, B cells selected by T follicular helper cells on the basis of successful antigen processing always return to the dark zone for asymmetric division, and acquired antigen is inherited by one daughter cell only. Antigen-retaining B cells differentiate to plasma cells and leave the germinal center through the dark zone. This theory has implications for the functioning of germinal centers because compared to previous models, high-affinity antibodies appear one day earlier and the amount of derived plasma cells is considerably larger.

  9. DNR Division of Parks and Trails District Boundaries

    Data.gov (United States)

    Minnesota Department of Natural Resources — This data shows the DNR Division of Parks and Trails District Boundaries as of May 2010. The boundaries were created by the Division Leadership Team. Boundaries are...

  10. Maintenance Management in the ST Division

    CERN Document Server

    Rühl, I

    2001-01-01

    The Maintenance Manager Working Group was established in order to revise existing maintenance contracts and to provide comprehensive and applicable tools for the execution of maintenance activities in the ST Division. This was necessary mainly due to the fact that the maintenance plans in the Division have often evolved rather than being consciously set up and in respect to the change towards result orientated contracts. Also, because the decrease of CERN staff and the trend towards outsourcing, a tighter and well-organised maintenance management has to be established. In order to achieve the most realistic and applicable results the technical and commercial aspects must be considered by following the industrial approach. This document will outline the objectives of the working group and will show the progress that has been made by the implementation of already achieved results. Furthermore this paper will show a possible structure of future maintenance management.

  11. Chemical Technology Division. Annual technical report, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Laidler, J.J.; Myles, K.M.; Green, D.W.; McPheeters, C.C.

    1996-06-01

    Highlights of the Chemical Technology (CMT) Division`s activities during 1995 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) methods for treatment of hazardous waste and mixed hazardous/radioactive waste; (3) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (4) processes for separating and recovering selected elements from waste streams, concentrating low-level radioactive waste streams with advanced evaporator technology, and producing {sup 99}Mo from low-enriched uranium; (5) electrometallurgical treatment of different types of spent nuclear fuel in storage at Department of Energy sites; and (6) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems.

  12. Competitive Equilibria in Economies with Multiple Divisible and Indivisible Commodities and No Money

    NARCIS (Netherlands)

    Koshevoy, G.A.; Talman, A.J.J.

    2006-01-01

    A general equilibrium model is considered with multiple divisible and multiple indivisible commodities.In models with indivisibles it is always assumed that an indivisible commodity, called money, is present that is used to transfer the value of certain amounts of indivisible goods.For these economi

  13. Energy and Environment Division annual report, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Camp, J.A. (ed.)

    1978-01-01

    Research activities of this Division are reported under nine separate programs, namely: Energy Analysis; Solar Energy; Energy-Efficient Buildings; Chemical Process Research and Development; Environmental Research; Atmospheric Aerosol Research; Oil Shale Research; Instrumentation Development; and Combustion Research. A separate abstract was prepared for each of the nine programs, each of which contained several individual research summaries, with responsible researchers listed. All of the abstracts will appear in Energy Research Abstracts (ERA), and five will appear in Energy Abstracts for Policy Analysis (EAPA).

  14. The Divisive Threat of Immigration in Europe

    Science.gov (United States)

    2012-12-01

    Europe , immigrant children consistently underperformed in reading. This disparity suggests that immigrant children will have lower literacy rates, less...OF IMMIGRATION IN EUROPE by Andrew J. Sheehan Lars W. Lilleby December 2012 Thesis Advisor: Gordon McCormick Second Reader: Anna...COVERED Master’s Thesis 4. TITLE AND SUBTITLE The Divisive Threat of Immigration in Europe 5. FUNDING NUMBERS 6. AUTHOR(S) Lars W. Lilleby

  15. Earth Sciences Division annual report 1980

    Energy Technology Data Exchange (ETDEWEB)

    1981-07-01

    Summaries of the highlights of programs in the Earth Sciences Division are presented under four headings; Geosciences, Geothermal Energy Development, Nuclear Waste Isolation, and Marine Sciences. Utilizing both basic and applied research in a wide spectrum of topics, these programs are providing results that will be of value in helping to secure the nation's energy future. Separate abstracts have been prepared for each project for inclusion in the Energy Data Base. (DMC)

  16. Women of the Solar Physics Division

    Science.gov (United States)

    Dupree, Andrea K.

    2007-05-01

    In 1970, when the Solar Physics Division was established, the invitation to become a founding member of the Division was extended by the Organizing Committee to a group of 61 solar scientists of which 4 were women (6.6%). At the first SPD meeting in Huntsville AL (1970), 11% of the papers were given by women. Near that time (1973), women accounted for 8% of all AAS members. The representation of women in the SPD has more than doubled in percentage since the first years. Currently, women comprise about 15.5% of SPD members which, however, is less than the percentage in the AAS general membership (18%) in March 2007. In the 37 years that the SPD has existed, women have frequently held the office of Treasurer and Secretary of the Division and made notable contributions. Elske V.P. Smith was elected the first Treasurer of the SPD and that began a long tradition. Women appear to be considered exceptionally trustworthy since they have been reelected and occupied the position of Treasurer for 75% of the available terms. The Office of SPD Secretary has seen a woman for 13% of the terms. Yet women are practically absent among those in the top leadership positions and in the lists of prize winners of the SPD. Among the 21 SPD Chairs, only 1 woman, Judith T. Karpen, has held that office. The Hale Prize has been awarded 19 times in almost 3 decades, and all of the awardees have been men. Several aspects of the participation of women and their contributions to the Solar Physics Division of the AAS will be reviewed, and compared to that of the AAS and astronomy in general.

  17. On Certain Divisibility Property of Polynomials

    CERN Document Server

    Caceres, Luis F

    2010-01-01

    We review the definition of D-rings introduced by H. Gunji & D. L. MacQuillan. We provide an alternative characterization for such rings that allows us to give an elementary proof of that a ring of algebraic integers is a D-ring. Moreover, we give a characterization for D-rings that are also unique factorization domains to determine divisibility of polynomials using polynomial evaluations.

  18. Information Technology Division Technical Paper Abstracts 1995,

    Science.gov (United States)

    2007-11-02

    Information Technology Division (ITD), one of the largest research and development collectives at the Naval Research Laboratory. The abstracts are organized into sections that represent the six branches with ITD: the Navy Center for Applied Research in Artificial Intelligence, Communications Systems, the Center for High Assurance Computer Systems, Transmission Technology, Advanced Information Technology , and the Center for Computational Science. Within each section, a list of branch papers published in 1993 and 1994 has also been included; abstracts

  19. A combinatorial divisibility question from noncommutative algebra

    OpenAIRE

    2016-01-01

    We present a general conjecture on the divisibility of a certain expression in terms of Kostka numbers and their close variants. This conjecture is closely related to a variant of the period-index problem of noncommutative algebra, with partial implications in both directions. We present a description of the connection between these two problems via Schubert calculus as motivation and evidence for the conjecture before turning to a proof of the conjecture in a family of cases.

  20. Division algebras, extended supersymmetries and applications

    Energy Technology Data Exchange (ETDEWEB)

    Toppan, F. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    2001-03-01

    I present here some new results which make explicit the role of the division algebras R, C, H, O in the construction and classification of, respectively, N= 1, 2, 4, 8 global supersymmetric quantum mechanical and classical dynamical systems. In particular an N=8 Malcev superaffine algebra is introduced and its relation to the non-associative N = 8 SCA is discussed. A list of present and possible future applications is given. (author)

  1. Unpacking the Division Interpretation of a Fraction

    Science.gov (United States)

    Poon, Rebecca C.; Lewis, Priscilla Eide

    2015-01-01

    One of the challenges in learning fractions is understanding how and why a fraction can have multiple interpretations. As presented in one textbook, a fraction is "a symbol, such as 2/3, 5/1, or 8/5, used to name a part of a whole, a part of a set, a location on a number line, or a division of whole numbers" (Charles et al. 2012, p.…

  2. About the Mid-Continent Ecology Division (MED) of EPA's National Health and Environmental Effects Research Laboratory

    Science.gov (United States)

    The Mid-Continent Ecology Division (MED) conducts innovative research and predictive modeling to document and forecast the effects of pollutants on the integrity of watersheds and freshwater ecosystems.

  3. Bilateral high division of sciatic nerve

    Directory of Open Access Journals (Sweden)

    K. Shwetha

    2014-08-01

    Full Text Available Sciatic nerve is the thickest nerve in the body formed by the sacral plexus from L4 to S3 in the lesser pelvis. It emerges through the greater sciatic foramen below the piriformis and enter the gluteal region. Then the nerve passes on the back of the thigh and at the level of superior angle of popliteal fossa it terminates by dividing into tibial and common peroneal nerve. The knowledge of anatomical variations in the division of nerve is important for various surgical and anaesthetic procedures. During routine dissection in the department of anatomy, Mysore Medical College and Research Institute, Mysore, a rare bilateral high division of sciatic nerve was observed in a female cadaver aged about 40 years. In the present case there was bilateral high division of sciatic nerve. The nerve was seen dividing into two branches before it emerges through the greater sciatic foramen. The tibial nerve was entering the gluteal region below the piriformis muscle and common peroneal nerve was entering by piercing the piriformis. The knowledge of this variation is important as the nerve may get compressed with surrounding anatomical structures resulting in non discogenic sciatica. The awareness of variations is important for surgeons during various procedures like fracture, posterior dislocation of hip joint and hip joint replacement. The anatomical variations are important during deep intramuscular injections in gluteal region and also for anaesthetists during sciatic nerve block. [Int J Res Med Sci 2014; 2(4.000: 1785-1787

  4. Chemical Technology Division, Annual technical report, 1991

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    Highlights of the Chemical Technology (CMT) Division`s activities during 1991 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion and coal-fired magnetohydrodynamics; (3) methods for treatment of hazardous and mixed hazardous/radioactive waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (5) processes for separating and recovering transuranic elements from nuclear waste streams; (6) recovery processes for discharged fuel and the uranium blanket in the Integral Fast Reactor (IFR); (7) processes for removal of actinides in spent fuel from commercial water-cooled nuclear reactors and burnup in IFRs; and (8) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources; chemistry of superconducting oxides and other materials of interest with technological application; interfacial processes of importance to corrosion science, catalysis, and high-temperature superconductivity; and the geochemical processes involved in water-rock interactions occurring in active hydrothermal systems. In addition, the Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the technical programs at Argonne National Laboratory (ANL).

  5. Chemical Technology Division annual technical report, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    Highlights of the Chemical Technology (CMT) Division`s activities during 1994 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion; (3) methods for treatment of hazardous waste and mixed hazardous/radioactive waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (5) processes for separating and recovering transuranic elements from waste streams, concentrating radioactive waste streams with advanced evaporator technology, and producing {sup 99}Mo from low-enriched uranium for medical applications; (6) electrometallurgical treatment of the many different types of spent nuclear fuel in storage at Department of Energy sites; and (8) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources and novel ceramic precursors; materials chemistry of superconducting oxides, electrified metal/solution interfaces, molecular sieve structures, and impurities in scrap copper and steel; and the geochemical processes involved in mineral/fluid interfaces and water-rock interactions occurring in active hydrothermal systems. In addition, the Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the technical programs at Argonne National Laboratory (ANL).

  6. Physics Division Argonne National Laboratory description of the programs and facilities.

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, K.J. [ed.

    1999-05-24

    The ANL Physics Division traces its roots to nuclear physics research at the University of Chicago around the time of the second world war. Following the move from the University of Chicago out to the present Argonne site and the formation of Argonne National Laboratory: the Physics Division has had a tradition of research into fundamental aspects of nuclear and atomic physics. Initially, the emphasis was on areas such as neutron physics, mass spectrometry, and theoretical studies of the nuclear shell model. Maria Goeppert Maier was an employee in the Physics Division during the time she did her Nobel-Prize-winning work on the nuclear shell model. These interests diversified and at the present time the research addresses a wide range of current problems in nuclear and atomic physics. The major emphasis of the current experimental nuclear physics research is in heavy-ion physics, centered around the ATLAS facility (Argonne Tandem-Linac Accelerator System) with its new injector providing intense, energetic ion beams over the fill mass range up to uranium. ATLAS is a designated National User Facility and is based on superconducting radio-frequency technology developed in the Physics Division. A small program continues in accelerator development. In addition, the Division has a strong program in medium-energy nuclear physics carried out at a variety of major national and international facilities. The nuclear theory research in the Division spans a wide range of interests including nuclear dynamics with subnucleonic degrees of freedom, dynamics of many-nucleon systems, nuclear structure, and heavy-ion interactions. This research makes contact with experimental research programs in intermediate-energy and heavy-ion physics, both within the Division and on the national and international scale. The Physics Division traditionally has strong connections with the nation's universities. We have many visiting faculty members and we encourage students to participate in our

  7. Couples' attitudes, childbirth and the division of labour

    NARCIS (Netherlands)

    Jansen, M.; Liefbroer, A.C.

    2006-01-01

    In this article, the authors examine effects of partners’ attitudes on the timing of the birth of a first child, the division of domestic labor, the division of child care, and the division of paid labor of couples. They use data from the Panel Study of Social Integration in the Netherlands, which i

  8. Formative cell divisions: principal determinants of plant morphogenesis.

    Science.gov (United States)

    Smolarkiewicz, Michalina; Dhonukshe, Pankaj

    2013-03-01

    Formative cell divisions utilizing precise rotations of cell division planes generate and spatially place asymmetric daughters to produce different cell layers. Therefore, by shaping tissues and organs, formative cell divisions dictate multicellular morphogenesis. In animal formative cell divisions, the orientation of the mitotic spindle and cell division planes relies on intrinsic and extrinsic cortical polarity cues. Plants lack known key players from animals, and cell division planes are determined prior to the mitotic spindle stage. Therefore, it appears that plants have evolved specialized mechanisms to execute formative cell divisions. Despite their profound influence on plant architecture, molecular players and cellular mechanisms regulating formative divisions in plants are not well understood. This is because formative cell divisions in plants have been difficult to track owing to their submerged positions and imprecise timings of occurrence. However, by identifying a spatiotemporally inducible cell division plane switch system applicable for advanced microscopy techniques, recent studies have begun to uncover molecular modules and mechanisms for formative cell divisions. The identified molecular modules comprise developmentally triggered transcriptional cascades feeding onto microtubule regulators that now allow dissection of the hierarchy of the events at better spatiotemporal resolutions. Here, we survey the current advances in understanding of formative cell divisions in plants in the context of embryogenesis, stem cell functionality and post-embryonic organ formation.

  9. 28 CFR 3.2 - Assistant Attorney General, Criminal Division.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Assistant Attorney General, Criminal Division. 3.2 Section 3.2 Judicial Administration DEPARTMENT OF JUSTICE GAMBLING DEVICES § 3.2 Assistant Attorney General, Criminal Division. The Assistant Attorney General, Criminal Division, is authorized to...

  10. Couples’ Attitudes, Childbirth, and the Division of Labor

    NARCIS (Netherlands)

    Jansen, Miranda; Liefbroer, Aart C.

    2006-01-01

    In this article, the authors examine effects of partners’ attitudes on the timing of the birth of a first child, the division of domestic labor, the division of child care, and the division of paid labor of couples. They use data from the Panel Study of Social Integration in the Netherlands, which i

  11. 15 CFR 950.8 - Satellite Data Services Division (SDSD).

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Satellite Data Services Division (SDSD... THE ENVIRONMENTAL DATA SERVICE ENVIRONMENTAL DATA AND INFORMATION § 950.8 Satellite Data Services Division (SDSD). The Satellite Data Services Division of the EDIS National Climatic Center...

  12. Couples’ Attitudes, Childbirth, and the Division of Labor

    NARCIS (Netherlands)

    Jansen, Miranda; Liefbroer, Aart C.

    2006-01-01

    In this article, the authors examine effects of partners’ attitudes on the timing of the birth of a first child, the division of domestic labor, the division of child care, and the division of paid labor of couples. They use data from the Panel Study of Social Integration in the Netherlands, which i

  13. Couples' Attitudes, Childbirth, and the Division of Labor

    Science.gov (United States)

    Jansen, Miranda; Liefbroer, Aart C.

    2006-01-01

    In this article, the authors examine effects of partners' attitudes on the timing of the birth of a first child, the division of domestic labor, the division of child care, and the division of paid labor of couples. They use data from the Panel Study of Social Integration in the Netherlands, which includes independent measures of both partners'…

  14. Reconciling Divisions in the Field of Authentic Education

    Science.gov (United States)

    Sarid, Ariel

    2015-01-01

    The aim of this article is twofold: first, to identify and address three central divisions in the field of authentic education that introduce ambiguity and at times inconsistencies within the field of authentic education. These divisions concern a) the relationship between autonomy and authenticity; b) the division between the two basic attitudes…

  15. 25 CFR 11.800 - Jurisdiction of appellate division.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Jurisdiction of appellate division. 11.800 Section 11.800... LAW AND ORDER CODE Appellate Proceedings § 11.800 Jurisdiction of appellate division. The jurisdiction of the appellate division shall extend to all appeals from final orders and judgments of the...

  16. 32 CFR 516.36 - Referral to Litigation Division.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Referral to Litigation Division. 516.36 Section... Property Claims Assertion of Other Claims § 516.36 Referral to Litigation Division. (a) General. The... channels to Litigation Division with a litigation report. (See § 516.23 of this part). (b)...

  17. Divisibility and Multiplicative Structure of Natural Numbers: Preservice Teachers' Understanding.

    Science.gov (United States)

    Zazkis, Rina; Campbell, Stephen

    1996-01-01

    Elementary number theory is investigated with the main focus on the concept of divisibility and its relation to division, multiplication, prime and composite numbers, factorization, divisibility rules, and prime decomposition. Preservice teachers' responses indicated dispositions toward procedural attachments even when conceptual understanding was…

  18. Sexual division of labor: energetic and evolutionary scenarios.

    Science.gov (United States)

    Panter-Brick, Catherine

    2002-01-01

    This article examines comparative energetic data on hunter-gatherers in the context of evolutionary scenarios of the sexual division of labor, with respect to both specific task allocation and overall levels of daily physical activity. The division of labor between men and women, well marked in contemporary foraging societies, was once posited as the "true watershed" for the evolution of the genus Homo. Some research on brain-wiring even links sex differences in cognitive and spatial abilities to sex-specific foraging activities. Most recent evolutionary arguments posit that men focus on hunting and women on gathering activities to realize potentially conflicting mating and parenting goals. A range of cooperative strategies (male/female and female/female) for child provisioning is also under investigation. Attention to energetic and reproductive trade-offs has usefully challenged the proposition that women are excluded from big-game hunting due to constraints of foraging ecology and reproduction. Simplistic assumptions about gender roles are thus increasingly questioned in anthropology, as well as in archaeology. Current models in behavioral ecology explore ways in which foraging practices vary with ecological circumstances, aiming to derive testable hypotheses from fine-grained data on the behavior of contemporary hunter-gatherers. Data on overall physical activity levels (PAL) can also serve to evaluate relative male/female workloads in modern groups, reconstruct hominid energy requirements and activity profiles, and examine changes with subsistence intensification. Male/female PAL ratios show that a task-specific division of labor does not readily extrapolate to 24-hour energy expenditure and that male/female differences in workloads were not necessarily reduced with the transition to agriculture. With respect to gender roles and PAL, a shift away from facile stereotypes of human behavior is evident. The challenge is to incorporate a range of behavioral

  19. Polarity in plant asymmetric cell division: Division orientation and cell fate differentiation.

    Science.gov (United States)

    Shao, Wanchen; Dong, Juan

    2016-11-01

    Asymmetric cell division (ACD) is universally required for the development of multicellular organisms. Unlike animal cells, plant cells have a rigid cellulosic extracellular matrix, the cell wall, which provides physical support and forms communication routes. This fundamental difference leads to some unique mechanisms in plants for generating asymmetries during cell division. However, plants also utilize intrinsically polarized proteins to regulate asymmetric signaling and cell division, a strategy similar to the differentiation mechanism found in animals. Current progress suggests that common regulatory modes, i.e. protein spontaneous clustering and cytoskeleton reorganization, underlie protein polarization in both animal and plant cells. Despite these commonalities, it is important to note that intrinsic mechanisms in plants are heavily influenced by extrinsic cues. To control physical asymmetry in cell division, although our understanding is fragmentary thus far, plants might have evolved novel polarization strategies to orientate cell division plane. Recent studies also suggest that the phytohormone auxin, one of the most pivotal small molecules in plant development, regulates ACD in plants. Copyright © 2016. Published by Elsevier Inc.

  20. Sonic Hedgehog Signaling Switches the Mode of Division in the Developing Nervous System

    Directory of Open Access Journals (Sweden)

    Murielle Saade

    2013-08-01

    Full Text Available The different modes of stem cell division are tightly regulated to balance growth and differentiation during organ development and homeostasis, and these regulatory processes are subverted in tumor formation. Here, we developed markers that provided the single-cell resolution necessary to quantify the three modes of division taking place in the developing nervous system in vivo: self-expanding, PP; self-replacing, PN; and self-consuming, NN. Using these markers and a mathematical model that predicts the dynamics of motor neuron progenitor division, we identify a role for the morphogen Sonic hedgehog in the maintenance of stem cell identity in the developing spinal cord. Moreover, our study provides insight into the process linking lineage commitment to neurogenesis with changes in cell-cycle parameters. As a result, we propose a challenging model in which the external Sonic hedgehog signal dictates stem cell identity, reflected in the consequent readjustment of cell-cycle parameters.

  1. Cell divisions are not essential for the direct conversion of fibroblasts into neuronal cells.

    Science.gov (United States)

    Fishman, V S; Shnayder, T A; Orishchenko, K E; Bader, M; Alenina, N; Serov, O L

    2015-01-01

    Direct lineage conversion is a promising approach for disease modeling and regenerative medicine. Cell divisions play a key role in reprogramming of somatic cells to pluripotency, however their role in direct lineage conversion is not clear. Here we used transdifferentiation of fibroblasts into neuronal cells by forced expression of defined transcription factors as a model system to study the role of cellular division in the direct conversion process. We have shown that conversion occurs in the presence of the cell cycle inhibitors aphidicolin or mimosine. Moreover, overexpression of the cell cycle activator cMyc negatively influences the process of direct conversion. Overall, our results suggest that cell divisions are not essential for the direct conversion of fibroblasts into neuronal cells.

  2. Three Dimensional Simulation Method in Early Process of Division and Growth for Tumour Cells

    Institute of Scientific and Technical Information of China (English)

    XIA Zhi-qiu; ZHAO Ting-ting

    2014-01-01

    The process of division, growth and death for tumour cell mass in the early is simulated. An integrated GUI is provided for users to set the value of each parameters, which are cell growth rates, cell mass division rates, cell mass death rates, simulate type, maximum running time, polarity and cell colour. It can display the growth process of each cell on result GUI. Also, it can display the values of each parameters for observing and analysing in current life cycle on result GUI, which are cell mass division times, cell mass death rate, cell mass division rate and cell mass growth rate. In the process of simulation, The cell growth rate is described by the approach to combine the exponential model with the linear model. In addition, a linked list data structure to store the tumour cells is used by the cellular automata for a reference to determine the position of each cell. It sets up two linked list to store the cells, one of them save the new small division cells and the other one save the big cell. That can make the painting process of cells on result GUI clearer and more organized. At last, the polarity of tumour growth is described for determining the growth direction of cells.

  3. Biology Division progress report, October 1, 1993--September 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    This Progress Report summarizes the research endeavors of the Biology Division of the Oak Ridge National Laboratory during the period October 1, 1993, through September 30, 1995. The report is structured to provide descriptions of current activities and accomplishments in each of the Division`s major organizational units. Lists of information to convey the entire scope of the Division`s activities are compiled at the end of the report. Attention is focused on the following research activities: molecular, cellular, and cancer biology; mammalian genetics and development; genome mapping program; and educational activities.

  4. N-person envy-free chore division

    CERN Document Server

    Peterson, Elisha

    2009-01-01

    In contrast to the classical cake-cutting problem (how to fairly divide a desirable object), "chore division" is the problem of how to divide an undesirable object. We develop the first explicit algorithm for envy-free chore division among N people, a counterpart to the N-person envy-free cake-division solution of Brams-Taylor (1995). This is accomplished by exploiting a notion of "irrevocable advantage" for chores. We discuss the differences between cake-cutting and chore division and additional problems encountered in chore division.

  5. Gaussian Beams Tracing and Predicting Model Based on Space Quad-tree Division%基于空间四叉树分区的高斯波束跟踪预测模型

    Institute of Scientific and Technical Information of China (English)

    任佳敏; 徐大专; 朱秋明; 唐亚平; 周生奎

    2013-01-01

    As to using radio wave propagation prediction in urban areas, the process of intersection detection for the tracing of Gaussian beams is too complicated, this paper proposes a space division method based on quad-tree to equally distribute the obstacles of the scene into a series of sub-space and accurately locate the grids where the axis of the beams cross through. Simulation result shows that the accelerated Gaussian beam tracing method is roughly equal than and as accurate as ray racing, but prediction efficiency can be increased several times, which is quite useful for the design and optimization of wireless network.%在城市环境中运用三维高斯波束跟踪进行电波传播预测时,障碍物碰撞的波束跟踪过程较为复杂。为此,提出一种基于空间四叉树的加速算法,将仿真场景进行层次分区,保证建筑物在各个分区中得到均匀分配,通过准确定位射线经过的分区,减少相交测试的数目。仿真结果表明,该算法的预测精度与传统射线跟踪法基本相当,但预测效率可提高数十倍,可用于辅助无线网络的规划、设计和优化。

  6. Section III, Division 5 - Development and Future Directions

    Energy Technology Data Exchange (ETDEWEB)

    D. K. Morton; R I Jetter; James E Nestell; T. D. Burchell; T L (Sam) Sham

    2012-07-01

    This paper provides commentary on a new division under Section III of the ASME Boiler and Pressure Vessel (BPV) Code. This new Division 5 has an issuance date of November 1, 2011 and is part of the 2011 Addenda to the 2010 Edition of the BPV Code. The new Division covers the rules for the design, fabrication, inspection and testing of components for high temperature nuclear reactors. Information is provided on the scope and need for Division 5, the structure of Division 5, where the rules originated, the various changes made in finalizing Division 5, and the future near-term and long-term expectations for Division 5 development. Portions of this paper were based on Chapter 17 of the Companion Guide to the ASME Boiler & Pressure Vessel Code, Fourth Edition, © ASME, 2012, Reference.

  7. Physics division. Progress report, January 1, 1995--December 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, M.; Bacon, D.S.; Aine, C.J.; Bartsch, R.R. [eds.] [comps.] [and others

    1997-10-01

    This issue of the Physics Division Progress Report describes progress and achievements in Physics Division research during the period January 1, 1995-December 31, 1996. The report covers the five main areas of experimental research and development in which Physics Division serves the needs of Los Alamos National Laboratory and the nation in applied and basic sciences: (1) biophysics, (2) hydrodynamic physics, (3) neutron science and technology, (4) plasma physics, and (5) subatomic physics. Included in this report are a message from the Division Director, the Physics Division mission statement, an organizational chart, descriptions of the research areas of the five groups in the Division, selected research highlights, project descriptions, the Division staffing and funding levels for FY95-FY97, and a list of publications and presentations.

  8. Myo19 ensures symmetric partitioning of mitochondria and coupling of mitochondrial segregation to cell division.

    Science.gov (United States)

    Rohn, Jennifer L; Patel, Jigna V; Neumann, Beate; Bulkescher, Jutta; Mchedlishvili, Nunu; McMullan, Rachel C; Quintero, Omar A; Ellenberg, Jan; Baum, Buzz

    2014-11-03

    During animal cell division, an actin-based ring cleaves the cell into two. Problems with this process can cause chromosome missegregation and defects in cytoplasmic inheritance and the partitioning of organelles, which in turn are associated with human diseases. Although much is known about how chromosome segregation is coupled to cell division, the way organelles coordinate their inheritance during partitioning to daughter cells is less well understood. Here, using a high-content live-imaging small interfering RNA screen, we identify Myosin-XIX (Myo19) as a novel regulator of cell division. Previously, this actin-based motor was shown to control the interphase movement of mitochondria. Our analysis shows that Myo19 is indeed localized to mitochondria and that its silencing leads to defects in the distribution of mitochondria within cells and in mitochondrial partitioning at division. Furthermore, many Myo19 RNAi cells undergo stochastic division failure--a phenotype that can be mimicked using a treatment that blocks mitochondrial fission and rescued by decreasing mitochondrial fusion, implying that mitochondria can physically interfere with cytokinesis. Strikingly, using live imaging we also observe the inappropriate movement of mitochondria to the poles of spindles in cells depleted for Myo19 as they enter anaphase. Since this phenocopies the results of an acute loss of actin filaments in anaphase, these data support a model whereby the Myo19 actin-based motor helps to control mitochondrial movement to ensure their faithful segregation during division. The presence of DNA within mitochondria makes their inheritance an especially important aspect of symmetrical cell division. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Multidiameter optical ring and Hermite-Gaussian vortices for wavelength division multiplexing-mode division multiplexing

    Science.gov (United States)

    Amphawan, Angela; Fazea, Yousef

    2016-10-01

    Optical vortices are high-capacity data carriers for mode division multiplexing (MDM) in multimode fiber (MMF). This paper reports on the MDM of a combination of helical-phased optical vortices comprising donut modes and Hermite-Gaussian (HG) modes for different radial offsets from the MMF axis. A data rate of 44 Gbps is achieved for wavelength division multiplexing-MDM of two pairs of helical-phased donut mode and HG mode at wavelengths 1550.12 and 1551.72 nm for a MMF length of 1500 m.

  10. Physics division annual report - October 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, K. [ed.

    2000-10-16

    This report summarizes the research performed in the past year in the Argonne Physics Division. The Division's programs include operation of ATLAS as a national heavy-ion user facility, nuclear structure and reaction research with beams of heavy ions, accelerator research and development especially in superconducting radio frequency technology, nuclear theory and medium energy nuclear physics. The Division took significant strides forward in its science and its initiatives for the future in the past year. Major progress was made in developing the concept and the technology for the future advanced facility of beams of short-lived nuclei, the Rare Isotope Accelerator. The scientific program capitalized on important instrumentation initiatives with key advances in nuclear science. In 1999, the nuclear science community adopted the Argonne concept for a multi-beam superconducting linear accelerator driver as the design of choice for the next major facility in the field a Rare Isotope Accelerator (RIA) as recommended by the Nuclear Science Advisory Committee's 1996 Long Range Plan. Argonne has made significant R&D progress on almost all aspects of the design concept including the fast gas catcher (to allow fast fragmentation beams to be stopped and reaccelerated) that in large part, defined the RIA concept the superconducting rf technology for the driver accelerator, the multiple-charge-state concept (to permit the facility to meet the design intensity goals with existing ion-source technology), and designs and tests of high-power target concepts to effectively deal with the full beam power of the driver linac. An NSAC subcommittee recommended the Argonne concept and set as tie design goal Uranium beams of 100-kwatt power at 400 MeV/u. Argonne demonstrated that this goal can be met with an innovative, but technically in-hand, design.

  11. Chemical Technology Division annual technical report, 1986

    Energy Technology Data Exchange (ETDEWEB)

    1987-06-01

    Highlights of the Chemical Technology (CMT) Division's activities during 1986 are presented. In this period, CMT conducted research and development in areas that include the following: (1) high-performance batteries - mainly lithium-alloy/metal sulfide and sodium/sulfur; (2) aqueous batteries (lead-acid, nickel/iron, etc.); (3) advanced fuel cells with molten carbonate or solid oxide electrolytes; (4) coal utilization, including the heat and seed recovery technology for coal-fired magnetohydrodynamics plants, the technology for fluidized-bed combustion, and a novel concept for CO/sub 2/ recovery from fossil fuel combustion; (5) methods for recovery of energy from municipal waste; (6) methods for the electromagnetic continuous casting of steel sheet; (7) techniques for treatment of hazardous waste such as reactive metals and trichloroethylenes; (8) nuclear technology related to waste management, a process for separating and recovering transuranic elements from nuclear waste, and the recovery processes for discharged fuel and the uranium blanket in a sodium-cooled fast reactor; and (9) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also has a program in basic chemistry research in the areas of catalytic hydrogenation and catalytic oxidation; materials chemistry for associated and ordered solutions at high temperatures; interfacial processes of importance to corrosion science, surface science, and catalysis; the thermochemistry of zeolites and related silicates; and the geochemical processes responsible for trace-element migration within the earth's crust. The Division continued to be the major user of the technical support provided by the Analytical Chemistry Laboratory at ANL. 127 refs., 71 figs., 8 tabs.

  12. Chemical Technology Division annual technical report 1989

    Energy Technology Data Exchange (ETDEWEB)

    1990-03-01

    Highlights of the Chemical Technology (CMT) Division's activities during 1989 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including high-performance batteries (mainly lithium/iron sulfide and sodium/metal chloride), aqueous batteries (lead-acid and nickel/iron), and advanced fuel cells with molten carbonate and solid oxide electrolytes: (2) coal utilization, including the heat and seed recovery technology for coal-fired magnetohydrodynamics plants and the technology for fluidized-bed combustion; (3) methods for recovery of energy from municipal waste and techniques for treatment of hazardous organic waste; (4) nuclear technology related to a process for separating and recovering transuranic elements from nuclear waste and for producing {sup 99}Mo from low-enriched uranium targets, the recovery processes for discharged fuel and the uranium blanket in a sodium-cooled fast reactor (the Integral Fast Reactor), and waste management; and (5) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also has a program in basic chemistry research in the areas of fluid catalysis for converting small molecules to desired products; materials chemistry for superconducting oxides and associated and ordered solutions at high temperatures; interfacial processes of importance to corrosion science, high-temperature superconductivity, and catalysis; and the geochemical processes responsible for trace-element migration within the earth's crust. The Division continued to be administratively responsible for and the major user of the Analytical Chemistry Laboratory at Argonne National Laboratory (ANL).

  13. Chemical technology division: Annual technical report 1987

    Energy Technology Data Exchange (ETDEWEB)

    1988-05-01

    Highlights of the Chemical Technology (CMT) Division's activities during 1987 are presented. In this period, CMT conducted research and development in the following areas: (1) high-performance batteries--mainly lithium-alloy/metal sulfide and sodium/sulfur; (2) aqueous batteries (lead-acid, nickel/iron, etc.); (3) advanced fuel cells with molten carbonate or solid oxide electrolytes; (4) coal utilization, including the heat and seed recovery technology for coal-fired magnetohydrodynamics plants and the technology for fluidized-bed combustion; (5) methods for the electromagnetic continuous casting of steel sheet and for the purification of ferrous scrap; (6) methods for recovery of energy from municipal waste and techniques for treatment of hazardous organic waste; (7) nuclear technology related to a process for separating and recovering transuranic elements from nuclear waste, the recovery processes for discharged fuel and the uranium blanket in a sodium-cooled fast reactor, and waste management; and (8) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also has a program in basic chemistry research in the areas of fluid catalysis for converting small molecules to desired products; materials chemistry for liquids and vapors at high temperatures; interfacial processes of importance to corrosion science, high-temperature superconductivity, and catalysis; the thermochemistry of various minerals; and the geochemical processes responsible for trace-element migration within the earth's crust. The Division continued to be the major user of the technical support provided by the Analytical Chemistry Laboratory at ANL. 54 figs., 9 tabs.

  14. Nuclear Science Division 1994 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Myers, W.D. [ed.

    1995-06-01

    This report describes the activities of the Nuclear Science Division for the period of January 1, 1994, to December 31, 1994. This was a time of significant accomplishment for all of the programs in the Division. Assembly of the solar neutrino detector at the Sudbury Neutrino Observatory is well under way. All of the components fabricated by LBL were shipped to Sudbury early in the year and our efforts are now divided between assisting the assembly of the detector and preparing software for data analysis once the detector is operational in 1996. Much of the activity at the 88-Inch Cyclotron centered on Gammasphere. The {open_quotes}early implementation{close_quotes} phase of the detector ended in September. This phase was extremely successful, involving over 60 experiments with nearly 200 users from 37 institutions worldwide. The mechanical structure was installed and the final electronic system is expected to operate in March 1995. The Division concurrently hosted a conference on physics for large {gamma}-ray detector arrays at the Clark Kerr Campus at UC Berkeley in August. This was a very successful meeting, reflecting the enthusiasm for this field worldwide. Also at the Cyclotron, the progress toward weak interaction experiments using ultra-thin sources passed a major milestone with the trapping of radioactive {sup 21}Na atoms. We are now engaged in a major upgrade of the experimental area and the outlook is very promising for these novel experiments. Another highlight of research at the Cyclotron was the confirmation of element 106. This development allowed the original LLNL/LBL discovery team to move forward with their proposal to name this element seaborgium.

  15. Laboratory Astrophysics Division of the AAS (LAD)

    Science.gov (United States)

    Salama, Farid; Drake, R. P.; Federman, S. R.; Haxton, W. C.; Savin, D. W.

    2012-01-01

    The purpose of the Laboratory Astrophysics Division (LAD) is to advance our understanding of the Universe through the promotion of fundamental theoretical and experimental research into the underlying processes that drive the Cosmos. LAD represents all areas of astrophysics and planetary sciences. The first new AAS Division in more than 30 years, the LAD traces its history back to the recommendation from the scientific community via the White Paper from the 2006 NASA-sponsored Laboratory Astrophysics Workshop. This recommendation was endorsed by the Astronomy and Astrophysics Advisory Committee (AAAC), which advises the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), and the U.S. Department of Energy (DOE) on selected issues within the fields of astronomy and astrophysics that are of mutual interest and concern to the agencies. In January 2007, at the 209th AAS meeting, the AAS Council set up a Steering Committee to formulate Bylaws for a Working Group on Laboratory Astrophysics (WGLA). The AAS Council formally established the WGLA with a five-year mandate in May 2007, at the 210th AAS meeting. From 2008 through 2012, the WGLA annually sponsored Meetings in-a-Meeting at the AAS Summer Meetings. In May 2011, at the 218th AAS meeting, the AAS Council voted to convert the WGLA, at the end of its mandate, into a Division of the AAS and requested draft Bylaws from the Steering Committee. In January 2012, at the 219th AAS Meeting, the AAS Council formally approved the Bylaws and the creation of the LAD. The inaugural gathering and the first business meeting of the LAD were held at the 220th AAS meeting in Anchorage in June 2012. You can learn more about LAD by visiting its website at http://lad.aas.org/ and by subscribing to its mailing list.

  16. Environmental Chemistry Division annual report, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Newman, L.

    1990-01-01

    The research activities making up the programs in the Environmental Chemistry Division of the Department of Applied Science are presented. Some of the more significant accomplishments during 1989 are described and plans for 1990 are discussed briefly. Publications for the period are listed and abstracts are provided. Research objectives and principal investigators are given for each of the active programs. A list of personnel and collaborators during the past year is presented. The support distribution of FY 1989 is approximately 85% from the Department of Energy (65% Office of Health and Environmental Research), and 15% other agencies (principally from the Electric Power Research Institute).

  17. Risk Bounds for Infinitely Divisible Distribution

    CERN Document Server

    Zhang, Chao

    2012-01-01

    In this paper, we study the risk bounds for samples independently drawn from an infinitely divisible (ID) distribution. In particular, based on a martingale method, we develop two deviation inequalities for a sequence of random variables of an ID distribution with zero Gaussian component. By applying the deviation inequalities, we obtain the risk bounds based on the covering number for the ID distribution. Finally, we analyze the asymptotic convergence of the risk bound derived from one of the two deviation inequalities and show that the convergence rate of the bound is faster than the result for the generic i.i.d. empirical process (Mendelson, 2003).

  18. Finite-dimensional division algebras over fields

    CERN Document Server

    Jacobson, Nathan

    2009-01-01

    Finite-Dimensional Division Algebras over fields determine, by the Wedderburn Theorem, the semi-simple finite-dimensional algebras over a field. They lead to the definition of the Brauer group and to certain geometric objects, the Brauer-Severi varieties. The book concentrates on those algebras that have an involution. Algebras with involution appear in many contexts; they arose first in the study of the so-called 'multiplication algebras of Riemann matrices'. The largest part of the book is the fifth chapter, dealing with involutorial simple algebras of finite dimension over a field. Of parti

  19. Activation of cell divisions in legume nodulation

    DEFF Research Database (Denmark)

    Nadzieja, Marcin

    Leguminous plants engage into symbiotic relationships with soil bacteria, rhizobia, and develop root nodules. This process initiates with recognition of bacteria derived signalling molecules called nod factors. The subsequent events lead to symbiotic infection and, occurring in parallel, de novo......) vasculature derived auxin contributes to auxin maxima in root cortex, vi) cytokinin and auxin cooperate with symbiotic transcription factors to determine position of the nodule founder cell and maintain cell divisions in nodule primordia, vii) deprivation of the vasculature derived auxin at the site...... regulation of symbiotic infection and organogenesis. Importantly, the developed tools and obtained results open new opportunities for future investigation of plant-rhizobia interaction....

  20. Ecological Research Division, Marine Research Program

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    This report presents program summaries of the various projects sponsored during 1979 by the Marine Research Program of the Ecological Research Division. Program areas include the effects of petroleum hydrocarbons on the marine environment; a study of the baseline ecology of a proposed OTEC site near Puerto Rico; the environmental impact of offshore geothermal energy development; the movement of radionuclides through the marine environment; the environmental aspects of power plant cooling systems; and studies of the physical and biological oceangraphy of the continental shelves bordering the United States.

  1. Quantum internet using code division multiple access

    CERN Document Server

    Zhang, Jing; Ozdemir, Sahin Kaya; Wu, Re-Bing; Wang, Xiang-Bin; Nori, Franco

    2012-01-01

    Code division multiple access (CDMA) is a spread-spectrum technology, in which a code is used to spread the spectral content of information to achieve larger network capacity. It has been widely used in classical communication and wireless networks. Here, we extend CDMA to the quantum case, where many pairs of nodes can transmit quantum information through a shared channel. This can be achieved by chaotic encoding of quantum information to spread its spectral content and by chaos synchronization, to separate different sender-receiver pairs. The proposed method is robust to low-frequency noise, and achieves faithful transmission with fidelities of up to 0.99.

  2. Wavelength division multiplexing a practical engineering guide

    CERN Document Server

    Grobe, Klaus

    2013-01-01

    In this book, Optical Wavelength Division Multiplexing (WDM) is approached from a strictly practical and application-oriented point of view. Based on the characteristics and constraints of modern fiber-optic components, transport systems and fibers, the text provides relevant rules of thumb and practical hints for technology selection, WDM system and link dimensioning, and also for network-related aspects such as wavelength assignment and resilience mechanisms. Actual 10/40 Gb/s WDM systems are considered, and a preview of the upcoming 100 Gb/s systems and technologies for even higher bit rate

  3. Research in the Division of Pharmaceutical Technology.

    Science.gov (United States)

    Junginger, H E

    1985-04-26

    Within the Center for Bio-Pharmaceutical Sciences the release characteristics of drugs form the major research object of the Division of Pharmaceutical Technology. Transdermal systems are being developed that can supply a drug during several days. Irritation of the skin may be avoided by using hydrogels. To enable long-term transdermal application also the colloidal structure of creams and ointments is investigated. As most drugs are to be taken orally, however, a research project was also started to make cheap and easy to produce controlled release tablets. The results with a microporous polypropylene polymer are promising.

  4. Time division multiple access for vehicular communications

    CERN Document Server

    Omar, Hassan Aboubakr

    2014-01-01

    This brief focuses on medium access control (MAC) in vehicular ad hoc networks (VANETs), and presents VeMAC, a novel MAC scheme based on distributed time division multiple access (TDMA) for VANETs. The performance of VeMAC is evaluated via mathematical analysis and computer simulations in comparison with other existing MAC protocols, including the IEEE 802.11p standard. This brief aims at proposing TDMA as a suitable MAC scheme for VANETs, which can support the quality-of-service requirements of high priority VANET applications.

  5. Long-term microfluidic tracking of coccoid cyanobacterial cells reveals robust control of division timing.

    Science.gov (United States)

    Yu, Feiqiao Brian; Willis, Lisa; Chau, Rosanna Man Wah; Zambon, Alessandro; Horowitz, Mark; Bhaya, Devaki; Huang, Kerwyn Casey; Quake, Stephen R

    2017-02-14

    Cyanobacteria are important agents in global carbon and nitrogen cycling and hold great promise for biotechnological applications. Model organisms such as Synechocystis sp. and Synechococcus sp. have advanced our understanding of photosynthetic capacity and circadian behavior, mostly using population-level measurements in which the behavior of individuals cannot be monitored. Synechocystis sp. cells are small and divide slowly, requiring long-term experiments to track single cells. Thus, the cumulative effects of drift over long periods can cause difficulties in monitoring and quantifying cell growth and division dynamics. To overcome this challenge, we enhanced a microfluidic cell-culture device and developed an image analysis pipeline for robust lineage reconstruction. This allowed simultaneous tracking of many cells over multiple generations, and revealed that cells expand exponentially throughout their cell cycle. Generation times were highly correlated for sister cells, but not between mother and daughter cells. Relationships between birth size, division size, and generation time indicated that cell-size control was inconsistent with the "sizer" rule, where division timing is based on cell size, or the "timer" rule, where division occurs after a fixed time interval. Instead, single cell growth statistics were most consistent with the "adder" rule, in which division occurs after a constant increment in cell volume. Cells exposed to light-dark cycles exhibited growth and division only during the light period; dark phases pause but do not disrupt cell-cycle control. Our analyses revealed that the "adder" model can explain both the growth-related statistics of single Synechocystis cells and the correlation between sister cell generation times. We also observed rapid phenotypic response to light-dark transitions at the single cell level, highlighting the critical role of light in cyanobacterial cell-cycle control. Our findings suggest that by monitoring the growth

  6. Physics, Computer Science and Mathematics Division annual report, January 1--December 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Lepore, J.V. (ed.)

    1977-01-01

    This annual report of the Physics, Computer Science and Mathematics Division describes the scientific research and other work carried out within the Division during the calendar year 1976. The Division is concerned with work in experimental and theoretical physics, with computer science and applied mathematics, and with the operation of a computer center. The major physics research activity is in high-energy physics; a vigorous program is maintained in this pioneering field. The high-energy physics research program in the Division now focuses on experiments with e/sup +/e/sup -/ colliding beams using advanced techniques and developments initiated and perfected at the Laboratory. The Division continues its work in medium energy physics, with experimental work carried out at the Bevatron and at the Los Alamos Pi-Meson Facility. Work in computer science and applied mathematics includes construction of data bases, computer graphics, computational physics and data analysis, mathematical modeling, and mathematical analysis of differential and integral equations resulting from physical problems. The computer center serves the Laboratory by constantly upgrading its facility and by providing day-to-day service. This report is descriptive in nature; references to detailed publications are given. (RWR)

  7. BRCA1 controls the cell division axis and governs ploidy and phenotype in human mammary cells.

    Science.gov (United States)

    He, Zhengcheng; Kannan, Nagarajan; Nemirovsky, Oksana; Chen, Helen; Connell, Marisa; Taylor, Brian; Jiang, Jihong; Pilarski, Linda M; Fleisch, Markus C; Niederacher, Dieter; Pujana, Miguel Angel; Eaves, Connie J; Maxwell, Christopher A

    2017-05-16

    BRCA1 deficiency may perturb the differentiation hierarchy present in the normal mammary gland and is associated with the genesis of breast cancers that are genomically unstable and typically display a basal-like transcriptome. Oriented cell division is a mechanism known to regulate cell fates and to restrict tumor formation. We now show that the cell division axis is altered following shRNA-mediated BRCA1 depletion in immortalized but non-tumorigenic, or freshly isolated normal human mammary cells with graded consequences in progeny cells that include aneuploidy, perturbation of cell polarity in spheroid cultures, and a selective loss of cells with luminal features. BRCA1 depletion stabilizes HMMR abundance and disrupts cortical asymmetry of NUMA-dynein complexes in dividing cells such that polarity cues provided by cell-matrix adhesions were not able to orient division. We also show that immortalized mammary cells carrying a mutant BRCA1 allele (BRCA1 185delAG/+) reproduce many of these effects but in this model, oriented divisions were maintained through cues provided by CDH1+ cell-cell junctions. These findings reveal a previously unknown effect of BRCA1 suppression on mechanisms that regulate the cell division axis in proliferating, non-transformed human mammary epithelial cells and consequent downstream effects on the mitotic integrity and phenotype control of their progeny.

  8. Colocalization and interaction between elongasome and divisome during a preparative cell division phase in Escherichia coli.

    Science.gov (United States)

    van der Ploeg, René; Verheul, Jolanda; Vischer, Norbert O E; Alexeeva, Svetlana; Hoogendoorn, Eelco; Postma, Marten; Banzhaf, Manuel; Vollmer, Waldemar; den Blaauwen, Tanneke

    2013-03-01

    The rod-shaped bacterium Escherichia coli grows by insertion of peptidoglycan into the lateral wall during cell elongation and synthesis of new poles during cell division. The monofunctional transpeptidases PBP2 and PBP3 are part of specialized protein complexes called elongasome and divisome, respectively, which catalyse peptidoglycan extension and maturation. Endogenous immunolabelled PBP2 localized in the cylindrical part of the cell as well as transiently at midcell. Using the novel image analysis tool Coli-Inspector to analyse protein localization as function of the bacterial cell age, we compared PBP2 localization with that of other E. coli cell elongation and division proteins including PBP3. Interestingly, the midcell localization of the two transpeptidases overlaps in time during the early period of divisome maturation. Försters Resonance Energy Transfer (FRET) experiments revealed an interaction between PBP2 and PBP3 when both are present at midcell. A decrease in the midcell diameter is visible after 40% of the division cycle indicating that the onset of new cell pole synthesis starts much earlier than previously identified by visual inspection. The data support a new model of the division cycle in which the elongasome and divisome interact to prepare for cell division.

  9. Understanding the role of asymmetric cell division in cancer using C. elegans.

    Science.gov (United States)

    Hyenne, Vincent; Chartier, Nicolas T; Labbé, Jean-Claude

    2010-05-01

    Asymmetric cell division is an important process to generate cell diversity and maintain tissue homeostasis. Recent evidence suggests that this process may also be crucial to prevent tumor formation. In the past 30 years, the embryo of the nematode Caenorhabditis elegans has proven to be a very powerful model to study the molecular and cellular basis of asymmetric cell division. Understanding this process in Caenorhabditis elegans may thus lead to a better understanding of stem cell function and tumorigenesis in humans. Copyright (c) 2010 Wiley-Liss, Inc.

  10. Comprehensiveness of pupils’ education, teachers’ training and teachers’ development at primary schools as a university division

    Directory of Open Access Journals (Sweden)

    Orosmán Hernández Estévez

    2014-07-01

    Full Text Available The paper describes the professional training of Bachelors in Primary Education in school functioning as university divisions. The paper’s objective is to suggest a system of actions to improve leadership and management of these institutions from the perspective of integrating the process of educating children, training professionally the pre-service teacher, and self-developing in-service teachers. Modelling the roll of the institution as a university division was the main result of the research; it includes the system of actions to be developed by pre-service teachers and ways for controlling them. Key words: Teachers’ education, tutorial, professional training.

  11. Chemical Technology Division annual technical report, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Battles, J.E.; Myles, K.M.; Laidler, J.J.; Green, D.W.

    1994-04-01

    Chemical Technology (CMT) Division this period, conducted research and development in the following areas: advanced batteries and fuel cells; fluidized-bed combustion and coal-fired magnetohydrodynamics; treatment of hazardous waste and mixed hazardous/radioactive waste; reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; separating and recovering transuranic elements, concentrating radioactive waste streams with advanced evaporators, and producing {sup 99}Mo from low-enriched uranium; recovering actinide from IFR core and blanket fuel in removing fission products from recycled fuel, and disposing removal of actinides in spent fuel from commercial water-cooled nuclear reactors; and physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources and novel ceramic precursors; materials chemistry of superconducting oxides, electrified metal/solution interfaces, molecular sieve structures, thin-film diamond surfaces, effluents from wood combustion, and molten silicates; and the geochemical processes involved in water-rock interactions. The Analytical Chemistry Laboratory in CMT also provides a broad range of analytical chemistry support.

  12. Effects of Polyhydroxybutyrate Production on Cell Division

    Science.gov (United States)

    Miller, Kathleen; Rahman, Asif; Hadi, Masood Z.

    2015-01-01

    Synthetic biological engineering can be utilized to aide the advancement of improved long-term space flight. The potential to use synthetic biology as a platform to biomanufacture desired equipment on demand using the three dimensional (3D) printer on the International Space Station (ISS) gives long-term NASA missions the flexibility to produce materials as needed on site. Polyhydroxybutyrates (PHBs) are biodegradable, have properties similar to plastics, and can be produced in Escherichia coli using genetic engineering. Using PHBs during space flight could assist mission success by providing a valuable source of biomaterials that can have many potential applications, particularly through 3D printing. It is well documented that during PHB production E. coli cells can become significantly elongated. The elongation of cells reduces the ability of the cells to divide and thus to produce PHB. I aim to better understand cell division during PHB production, through the design, building, and testing of synthetic biological circuits, and identify how to potentially increase yields of PHB with FtsZ overexpression, the gene responsible for cell division. Ultimately, an increase in the yield will allow more products to be created using the 3D printer on the ISS and beyond, thus aiding astronauts in their missions.

  13. Multiplexing photons with a binary division strategy

    Science.gov (United States)

    Schmiegelow, Christian Tomás; Larotonda, Miguel Antonio

    2014-08-01

    We present a scheme to produce clock-synchronized photons from a single parametric downconversion source with a binary division strategy. The time difference between a clock and detections of the herald photons determines the amount of delay that must be imposed to a photon by actively switching different temporal segments, so that all photons emerge from the output with their wavepackets temporally synchronized with the temporal reference. The operation is performed using a binary division configuration which minimizes the passages through switches. Finally, we extend this scheme to the production of many synchronized photons and find expressions for the optimal amount of correction stages as a function of the pair generation rate and the target coherence time. Our results show that, for the generation of this heralded single-photon per output state at an optimized input photon flux, the output rate of our scheme scales essentially with the reciprocal of the target output photon number. With current technology, rates of up to 104 synchronized pairs per second could be observed with only 7 correction stages.

  14. Chemical Technology Division, Annual technical report, 1991

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    Highlights of the Chemical Technology (CMT) Division's activities during 1991 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion and coal-fired magnetohydrodynamics; (3) methods for treatment of hazardous and mixed hazardous/radioactive waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (5) processes for separating and recovering transuranic elements from nuclear waste streams; (6) recovery processes for discharged fuel and the uranium blanket in the Integral Fast Reactor (IFR); (7) processes for removal of actinides in spent fuel from commercial water-cooled nuclear reactors and burnup in IFRs; and (8) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources; chemistry of superconducting oxides and other materials of interest with technological application; interfacial processes of importance to corrosion science, catalysis, and high-temperature superconductivity; and the geochemical processes involved in water-rock interactions occurring in active hydrothermal systems. In addition, the Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the technical programs at Argonne National Laboratory (ANL).

  15. Frequency division using a micromechanical resonance cascade

    Energy Technology Data Exchange (ETDEWEB)

    Qalandar, K. R., E-mail: kamala@engineering.ucsb.edu; Gibson, B.; Sharma, M.; Ma, A.; Turner, K. L. [Department of Mechanical Engineering, University of California at Santa Barbara, Santa Barbara, California 93106 (United States); Strachan, B. S. [Department of Mechanical Engineering, Michigan State University, East Lansing, Michigan 48823 (United States); Department of Electrical Engineering, Michigan State University, East Lansing, Michigan 48823 (United States); Shaw, S. W. [Department of Mechanical Engineering, Michigan State University, East Lansing, Michigan 48823 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48823 (United States)

    2014-12-15

    A coupled micromechanical resonator array demonstrates a mechanical realization of multi-stage frequency division. The mechanical structure consists of a set of N sequentially perpendicular microbeams that are connected by relatively weak elastic elements such that the system vibration modes are localized to individual microbeams and have natural frequencies with ratios close to 1:2:⋯:2{sup N}. Conservative (passive) nonlinear inter-modal coupling provides the required energy transfer between modes and is achieved by finite deformation kinematics. When the highest frequency beam is excited, this arrangement promotes a cascade of subharmonic resonances that achieve frequency division of 2{sup j} at microbeam j for j = 1, …, N. Results are shown for a capacitively driven three-stage divider in which an input signal of 824 kHz is passively divided through three modal stages, producing signals at 412 kHz, 206 kHz, and 103 kHz. The system modes are characterized and used to delineate the range of AC input voltages and frequencies over which the cascade occurs. This narrow band frequency divider has simple design rules that are scalable to higher frequencies and can be extended to a larger number of modal stages.

  16. The Astrophysics Science Division Annual Report 2009

    Science.gov (United States)

    Oegerle, William (Editor); Reddy, Francis (Editor); Tyler, Pat (Editor)

    2010-01-01

    The Astrophysics Science Division (ASD) at Goddard Space Flight Center (GSFC) is one of the largest and most diverse astrophysical organizations in the world, with activities spanning a broad range of topics in theory, observation, and mission and technology development. Scientific research is carried out over the entire electromagnetic spectrum - from gamma rays to radio wavelengths - as well as particle physics and gravitational radiation. Members of ASD also provide the scientific operations for three orbiting astrophysics missions - WMAP, RXTE, and Swift, as well as the Science Support Center for the Fermi Gamma-ray Space Telescope. A number of key technologies for future missions are also under development in the Division, including X-ray mirrors, space-based interferometry, high contrast imaging techniques to search for exoplanets, and new detectors operating at gamma-ray, X-ray, ultraviolet, infrared, and radio wavelengths. The overriding goals of ASD are to carry out cutting-edge scientific research, provide Project Scientist support for spaceflight missions, implement the goals of the NASA Strategic Plan, serve and support the astronomical community, and enable future missions by conceiving new concepts and inventing new technologies.

  17. Some new approaches to infinite divisibility

    CERN Document Server

    Sapatinas, Theofanis; Gupta, Arjun K

    2011-01-01

    Using an approach based, amongst other things, on Proposition 1 of Kaluza (1928), Goldie (1967) and, using a different approach based especially on zeros of polynomials, Steutel (1967) have proved that each nondegenerate distribution function (d.f.) $F$ (on $\\RR$, the real line), satisfying $F(0-) = 0$ and $F(x) = F(0) + (1-F(0)) G(x)$, $x > 0$, where $G$ is the d.f. corresponding to a mixture of exponential distributions, is infinitely divisible. Indeed, Proposition 1 of Kaluza (1928) implies that any nondegenerate discrete probability distribution ${p_x: x= 0,1, ...}$ that is log-convex or, in particular, completely monotone, is compound geometric, and, hence, infinitely divisible. Steutel (1970), Shanbhag & Sreehari (1977) and Steutel & van Harn (2004, Chapter VI) have given certain extensions or variations of one or more of these results. Following a modified version of the C.R. Rao et al. (2009, Section 4) approach based on the Wiener-Hopf factorization, we establish some further results of signi...

  18. Goddard's Astrophysics Science Division Annual Report 2013

    Science.gov (United States)

    Weaver, Kimberly A. (Editor); Reddy, Francis J. (Editor); Tyler, Patricia A. (Editor)

    2014-01-01

    The Astrophysics Science Division (ASD) at Goddard Space Flight Center (GSFC) is one of the largest and most diverse astrophysical organizations in the world, with activities spanning a broad range of topics in theory, observation, and mission and technology development. Scientific research is carried out over the entire electromagnetic spectrum from gamma rays to radio wavelengths as well as particle physics and gravitational radiation. Members of ASD also provide the scientific operations for two orbiting astrophysics missions Fermi Gamma-ray Space Telescope and Swift as well as the Science Support Center for Fermi. A number of key technologies for future missions are also under development in the Division, including X-ray mirrors, space-based interferometry, high contrast imaging techniques to search for exoplanets, and new detectors operating at gamma-ray, X-ray, ultraviolet, infrared, and radio wavelengths. The overriding goals of ASD are to carry out cutting-edge scientific research, provide Project Scientist support for spaceflight missions, implement the goals of the NASA Strategic Plan, serve and support the astronomical community, and enable future missions by conceiving new concepts and inventing new technologies.

  19. Goddard's Astrophysics Science Division Annual Report 2011

    Science.gov (United States)

    Centrella, Joan; Reddy, Francis; Tyler, Pat

    2012-01-01

    The Astrophysics Science Division(ASD) at Goddard Space Flight Center(GSFC)is one of the largest and most diverse astrophysical organizations in the world, with activities spanning a broad range of topics in theory, observation, and mission and technology development. Scientific research is carried out over the entire electromagnetic spectrum from gamma rays to radiowavelengths as well as particle physics and gravitational radiation. Members of ASD also provide the scientific operations for three orbiting astrophysics missions WMAP, RXTE, and Swift, as well as the Science Support Center for the Fermi Gamma-ray Space Telescope. A number of key technologies for future missions are also under development in the Division, including X-ray mirrors, space-based interferometry, high contract imaging techniques to serch for exoplanets, and new detectors operating at gamma-ray, X-ray, ultraviolet, infrared, and radio wavelengths. The overriding goals of ASD are to carry out cutting-edge scientific research, and provide Project Scientist support for spaceflight missions, implement the goals of the NASA Strategic Plan, serve and suppport the astronomical community, and enable future missions by conceiving new conepts and inventing new technologies.

  20. The architecture of the Cassini division

    Science.gov (United States)

    Hedman, M.M.; Nicholson, P.D.; Baines, K.H.; Buratti, B.J.; Sotin, Christophe; Clark, R.N.; Brown, R.H.; French, R.G.; Marouf, E.A.

    2010-01-01

    The Cassini Division in Saturn's rings contains a series of eight named gaps, three of which contain dense ringlets. Observations of stellar occultations by the Visual and Infrared Mapping Spectrometer onboard the Cassini spacecraft have yielded 40 accurate and precise measurements of the radial position of the edges of all of these gaps and ringlets. These data reveal suggestive patterns in the shapes of many of the gap edges: the outer edges of the five gaps without ringlets are circular to within 1 km, while the inner edges of six of the gaps are eccentric, with apsidal precession rates consistent with those expected for eccentric orbits near each edge. Intriguingly, the pattern speeds of these eccentric inner gap edges, together with that of the eccentric Huygens Ringlet, form a series with a characteristic spacing of 006 day-1. The two gaps with non-eccentric inner edges lie near first-order inner Lindblad resonances (ILRs) with moons. One such edge is close to the 5:4 ILR with Prometheus, and the radial excursions of this edge do appear to have an m = 5 component aligned with that moon. The other resonantly confined edge is the outer edge of the B ring, which lies near the 2:1 Mimas ILR. Detailed investigation of the B-ring-edge data confirm the presence of an m = 2 perturbation on the B-ring edge, but also show that during the course of the Cassini Mission, this pattern has drifted backward relative to Mimas. Comparisons with earlier occultation measurements going back to Voyager suggest the possibility that the m = 2 pattern is actually librating relative to Mimas with a libration frequency L 006 day-1 (or possibly 012 day -1). In addition to the m = 2 pattern, the B-ring edge also has an m = 1 component that rotates around the planet at a rate close to the expected apsidal precession rate (?? ?? ?? B ??? 5.??06 day -1). Thus, the pattern speeds of the eccentric edges in the Cassini Division can be generated from various combinations of the pattern speeds

  1. Primitive human hematopoietic cells give rise to differentially specified daughter cells upon their initial cell division.

    NARCIS (Netherlands)

    Giebel, B.; Zhang, T.; Beckmann, J.; Spanholtz, J.; Wernet, P.; Ho, A.; Punzel, M.

    2006-01-01

    It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive

  2. Informal Care and the Division of End-of-Life Transfers

    Science.gov (United States)

    Brown, Meta

    2006-01-01

    Unmarried parents in the AHEAD study derive the majority of their long-term care hours from their children, and child caregivers are generally unpaid. This paper examines the extent to which the division of end-of-life transfers compensates caregiving children. In a model of siblings' altruistic contribution of care to a shared parent, the…

  3. Managing Change in the Student Affairs Divisions of Higher Education Institutions

    Science.gov (United States)

    Lumadi, T. E.; Mampuru, K. C.

    2010-01-01

    In any institution of higher education the student affairs division is an ever-changing environment that necessitates an appropriate management approach. In view of this situation it was deemed necessary to identify a change model that would successfully manage change in student affairs. A literature review was done and an analysis of some…

  4. Primitive human hematopoietic cells give rise to differentially specified daughter cells upon their initial cell division.

    NARCIS (Netherlands)

    Giebel, B.; Zhang, T.; Beckmann, J.; Spanholtz, J.; Wernet, P.; Ho, A.; Punzel, M.

    2006-01-01

    It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive wh

  5. Undergraduate Experiences of Division I Athlete Science, Technology, Engineering, and Mathematics (STEM) Graduates

    Science.gov (United States)

    Comeaux, Eddie; Bachman, Tina; Burton, Rena M.; Aliyeva, Aida

    2017-01-01

    Employing the conceptual model developed by Comeaux and Harrison ("Coll Stud Aff J" 30(1):75-87, 2011), this study explored the undergraduate experience of Division I athlete STEM graduates. Data collection involved 17 in-depth interviews with former athletes at two research-intensive, public institutions. Results revealed that…

  6. Exploring Middle School Students' Conceptions of the Relationship between Genetic Inheritance and Cell Division

    Science.gov (United States)

    Williams, Michelle; DeBarger, Angela Haydel; Montgomery, Beronda L.; Zhou, Xuechun; Tate, Erika

    2012-01-01

    This study examines students' understanding of the normative connections between key concepts of cell division, including both mitosis and meiosis, and underlying biological principles that are critical for an in-depth understanding of genetic inheritance. Using a structural equation modeling method, we examine middle school students'…

  7. Scaling laws governing stochastic growth and division of single bacterial cells

    CERN Document Server

    Iyer-Biswas, Srividya; Henry, Jonathan T; Lo, Klevin; Burov, Stanislav; Lin, Yihan; Crooks, Gavin E; Crosson, Sean; Dinner, Aaron R; Scherer, Norbert F

    2014-01-01

    Uncovering the quantitative laws that govern the growth and division of single cells remains a major challenge. Using a unique combination of technologies that yields unprecedented statistical precision, we find that the sizes of individual Caulobacter crescentus cells increase exponentially in time. We also establish that they divide upon reaching a critical multiple ($\\approx$1.8) of their initial sizes, rather than an absolute size. We show that when the temperature is varied, the growth and division timescales scale proportionally with each other over the physiological temperature range. Strikingly, the cell-size and division-time distributions can both be rescaled by their mean values such that the condition-specific distributions collapse to universal curves. We account for these observations with a minimal stochastic model that is based on an autocatalytic cycle. It predicts the scalings, as well as specific functional forms for the universal curves. Our experimental and theoretical analysis reveals a ...

  8. Polarity and cell division orientation in the cleavage embryo: from worm to human

    Science.gov (United States)

    Ajduk, Anna; Zernicka-Goetz, Magdalena

    2016-01-01

    Cleavage is a period after fertilization, when a 1-cell embryo starts developing into a multicellular organism. Due to a series of mitotic divisions, the large volume of a fertilized egg is divided into numerous smaller, nucleated cells—blastomeres. Embryos of different phyla divide according to different patterns, but molecular mechanism of these early divisions remains surprisingly conserved. In the present paper, we describe how polarity cues, cytoskeleton and cell-to-cell communication interact with each other to regulate orientation of the early embryonic division planes in model animals such as Caenorhabditis elegans, Drosophila and mouse. We focus particularly on the Par pathway and the actin-driven cytoplasmic flows that accompany it. We also describe a unique interplay between Par proteins and the Hippo pathway in cleavage mammalian embryos. Moreover, we discuss the potential meaning of polarity, cytoplasmic dynamics and cell-to-cell communication as quality biomarkers of human embryos. PMID:26660321

  9. Offset phase locking of noisy diode lasers aided by frequency division

    Science.gov (United States)

    Ivanov, E. N.; Esnault, F.-X.; Donley, E. A.

    2011-08-01

    For heterodyne phase locking, frequency division of the beat note between two oscillators can improve the reliability of the phase lock and the quality of the phase synchronization. Frequency division can also reduce the size, weight, power, and cost of the instrument by excluding the microwave synthesizer from the control loop when the heterodyne offset frequency is large (5 to 10 GHz). We have experimentally tested the use of a frequency divider in an optical phase-lock loop and compared the achieved level of residual phase fluctuations between two diode lasers with that achieved without the use of a frequency divider. The two methods achieve comparable phase stability provided that sufficient loop gain is maintained after frequency division to preserve the required bandwidth. We have also numerically analyzed the noise properties and internal dynamics of phase-locked loops subjected to a high level of phase fluctuations, and our modeling confirms the expected benefits of having an in-loop frequency divider.

  10. A SURVEY ON WAVELENGTH DIVISION MULTIPLEXING (WDM NETWORKS

    Directory of Open Access Journals (Sweden)

    G. Ramesh

    2010-03-01

    Full Text Available Communication networks have emerged as a source of empowerment in today’s society. At the global level, the Internet is becoming the backbone of the modern economy. The new generations in developed countries cannot even conceive of a world without broadband access to the Internet. The inability of the current Internet infrastructure to cope with the wide variety and ever growing number of users, emerging networked applications, usage patterns and business models is increasingly being recognized worldwide. The dynamic growth of Internet traffic and its bursty nature requires high transmission rate. With the advances and the progress in Wavelength Division Multiplexing (WDM technology, the amount of raw bandwidth available in fiber links has increased to high magnitude. This paper presents a survey on WDM networks from its development to the current status. Also an analysis on buffer size in optical networks for real time traffic was performed.

  11. Spiking Neural P Systems with Neuron Division and Dissolution

    Science.gov (United States)

    Liu, Xiyu; Wang, Wenping

    2016-01-01

    Spiking neural P systems are a new candidate in spiking neural network models. By using neuron division and budding, such systems can generate/produce exponential working space in linear computational steps, thus provide a way to solve computational hard problems in feasible (linear or polynomial) time with a “time-space trade-off” strategy. In this work, a new mechanism called neuron dissolution is introduced, by which redundant neurons produced during the computation can be removed. As applications, uniform solutions to two NP-hard problems: SAT problem and Subset Sum problem are constructed in linear time, working in a deterministic way. The neuron dissolution strategy is used to eliminate invalid solutions, and all answers to these two problems are encoded as indices of output neurons. Our results improve the one obtained in Science China Information Sciences, 2011, 1596-1607 by Pan et al. PMID:27627104

  12. Distributing and Scheduling Divisible Task on Parallel Communicating Processors

    Institute of Scientific and Technical Information of China (English)

    李国东; 张德富

    2002-01-01

    In this paper we propose a novel scheme for scheduling divisible task onparallel processors connected by system interconnection network with arbitrary topology. Thedivisible task is a computation that can be divided into arbitrary independent subtasks solvedin parallel. Our model takes into consideration communication initial time and communicationdelays between processors. Moreover, by constructing the corresponding Network SpanningTree (NST) for a network, our scheme can be applied to all kinds of network topologies. Wepresent the concept of Balanced Task Distribution Tree and use it to design the Equation SetCreation Algorithm in which the set of linear equations is created by traversing the NST inpost-order. After solving the created equations, we get the optimal task assignment scheme.Experiments confirm the applicability of our scheme in real-life situations.

  13. Establishment of the new Ecuadorian solar physics phenomena division

    CERN Document Server

    Lopez, Ericson D

    2013-01-01

    Crucial physical phenomena occur in the equatorial atmosphere and ionosphere, which are currently understudied and poorly understood. Then, scientific campaigns for monitoring equatorial region are required, which will provide the data for analyzing and creating adequate models. Ecuador is located in strategic geographical position where these studies can be performed, providing data for the scientific community working for understanding the nature of these physical systems. The Quito Astronomical Observatory of National Polytechnic School is working in this direction, promoting research in Space Sciences for studying the equatorial zone. With the participation and valuable collaboration of international initiatives like AWESOME, MAGDAS, SAVNET and CALLISTO, the Quito Observatory is creating a new space physics division on the basis of the International Space Weather Initiative. In this contribution, the aforementioned initiative is presented inviting leaders from others scientific projects to deploy their in...

  14. Injury patterns in Division I collegiate swimming.

    Science.gov (United States)

    Wolf, Brian R; Ebinger, Alexander E; Lawler, Michael P; Britton, Carla L

    2009-10-01

    In the last 25 years, it is estimated that over 42,000 male and female swimmers have competed at the National Collegiate Athletic Association (NCAA) Division I-A level. Despite the magnitude of these numbers, little is known about the epidemiology of collegiate swimming injuries. Purpose To describe the pattern of injuries incurred for one NCAA Division I collegiate men's and women's swimming team over 5 seasons. Descriptive epidemiology study. Musculoskeletal and head injuries reported in the Sports Injury Management System for a Division I swimming team from 2002-2007 were identified. Gender, body part, year of eligibility, position, stroke specialty, scholarship status, and team activity during which the injury occurred and lost time were recorded. Risk of injury was assessed relative to gender, stroke specialty, and year of eligibility. From 2002-2007, 44 male and 50 female athletes competed for the University of Iowa swimming and diving team. The overall injury rates were estimated as 4.00 injuries per 1000 exposures for men and 3.78 injuries per 1000 exposures for women. Thirty-seven percent of injuries resulted in missed time. The shoulder/upper arm was the most frequently injured body part followed by the neck/back. Freshman swimmers suffered the most injuries as well as the highest mean number of injuries per swimmer. A significant pattern of fewer injuries in later years of eligibility was also demonstrated. The relative risk (RR) for injury was higher among nonfreestyle stroke specialties (RR, 1.33 [1.00-1.77]). Injury most often occurred as a result of, or during, practice for all swimmers. However, 38% of injuries were the result of team activities outside of practice or competition, such as strength training. No significant relationship was found between occurrence of injury and gender or scholarship status. There was no significant relationship between body part injured and stroke specialty. An increased number of total injuries and an increased risk

  15. Comprehensive Review on Divisible Load Theory: Concepts, Strategies, and Approaches

    Directory of Open Access Journals (Sweden)

    Shamsollah Ghanbari

    2014-01-01

    Full Text Available There is extensive literature concerning the divisible load theory. The divisible load theory is mainly applied for scheduling in the area of distributed computing. It is based on the fact that the load can be divided into some arbitrarily independent parts, in which each part can be processed independently by a processor. This paper reviews the literature concerning the divisible load theory, while focusing on the details of the basic concepts, approaches, strategies, typologies, and open problems.

  16. Joy Osborne, MS, MPA | Division of Cancer Prevention

    Science.gov (United States)

    Joy Osborne is the ARC Director for the Division of Cancer Prevention and the Division of Cancer Control and Population Sciences. The ARC (Administrative Resource Center) provides services to DCP in the areas of budget, contracts, grants, human resources, travel, space and facilities, and other administrative areas. Joy came to NCI in 1992 as a Presidential Management Intern and has worked with many of the NCI Divisions in both intramural and extramural. |

  17. Asymmetric zygote division: A mystery starting point of embryogenesis.

    Science.gov (United States)

    Zhao, Jing; Sun, Meng-Xiang

    2016-10-02

    In angiosperm, asymmetric zygote division is critical for embryogenesis. The molecular mechanism underlying this process has gained a great attention recently. Some players involve in the control of both accurate position and correct orientation of zygote division plane have been found, which provide useful clues for the extensive investigations. It is getting clear that both internal and external factors are involved in this complex regulatory mechanism and the asymmetric zygote division seems with great impact in cell fate determination and embryo pattern formation.

  18. Analytical Chemistry Division's sample transaction system

    Energy Technology Data Exchange (ETDEWEB)

    Stanton, J.S.; Tilson, P.A.

    1980-10-01

    The Analytical Chemistry Division uses the DECsystem-10 computer for a wide range of tasks: sample management, timekeeping, quality assurance, and data calculation. This document describes the features and operating characteristics of many of the computer programs used by the Division. The descriptions are divided into chapters which cover all of the information about one aspect of the Analytical Chemistry Division's computer processing.

  19. Protein segregation between dividing hematopoietic progenitor cells in the determination of the symmetry/asymmetry of cell division.

    Science.gov (United States)

    Nteliopoulos, Georgios; Gordon, Myrtle Y

    2012-09-20

    In the present study, we investigated how the symmetry/asymmetry of cell division in mitotic CD34(+) cells can be evaluated by determining the plane of cell division and the potential distribution of proteins between daughter cells. The orientation of the mitotic spindle is dependent upon the positioning of the centrosomes, which determine the plane of cell division and the sharing of proteins. If the functions of unequally shared proteins are relevant to the kinetics of cell division, they could determine whether the daughter cells undergo self-renewal or differentiation. The kinetic function of the proteins of interest was investigated using a colony-replating assay and carboxyfluorescein succinimidyl ester (CFSE) staining. We used Notch/Numb as a model system, since they have a role in balancing symmetric/asymmetric divisions. Mitotic cells were examined microscopically and centrosomal markers γ-tubulin/pericentrin were used with activated Notch-1 and Numb. We monitored the first crucial divisions by CFSE staining and found an inverse relationship between activated Notch and Numb expression, suggesting a reciprocal regulation. We suggest that the subpopulations expressing activated Notch or Numb have different cell fates. To determine the influence of Notch signaling on progenitor cell self-renewal, we used the γ-secretase inhibitor N-[N-(3,5-Difluorophenacetyl-L-alanyl)]-S-phenylglycine t-Butyl ester (DAPT). DAPT influences self-renewal/differentiation outcome by affecting the frequency of symmetric renewal divisions without affecting the rate of divisions. Overall, the purpose of this study was to establish a cellular system for predicting the symmetry/asymmetry of hematopoietic progenitor divisions at the level of centrosomes and protein distribution and to investigate the influence of these proteins on progenitor cell kinetics.

  20. ADP Analysis project for the Human Resources Management Division

    Science.gov (United States)

    Tureman, Robert L., Jr.

    1993-01-01

    The ADP (Automated Data Processing) Analysis Project was conducted for the Human Resources Management Division (HRMD) of NASA's Langley Research Center. The three major areas of work in the project were computer support, automated inventory analysis, and an ADP study for the Division. The goal of the computer support work was to determine automation needs of Division personnel and help them solve computing problems. The goal of automated inventory analysis was to find a way to analyze installed software and usage on a Macintosh. Finally, the ADP functional systems study for the Division was designed to assess future HRMD needs concerning ADP organization and activities.

  1. Local Instruction Theory on Division in Mathematics GASING

    Directory of Open Access Journals (Sweden)

    Rully Charitas Indra Prahmana

    2014-07-01

    Full Text Available Several studies on learning mathematics for rural area's student indicate that students have difficulty in understanding the concept of division operation. Students are more likely to be introduced by the use of the formula without involving the concept itself and learning division separate the concrete situation of learning process. This underlies the researcher to design division operation learning in the Mathematics of GASING (Math GASING, which always starts from concrete to abstract level. The research method used is a design research which describes how the Math GASING make a real contribution of students understanding in the concept of division operation.

  2. Quality Management Plan for the Environmental Assessment and Innovation Division

    Science.gov (United States)

    Quality management plan (QMP) which identifies the mission, roles, responsibilities of personnel with regard to quality assurance and quality management for the environmental assessment and innovation division.

  3. Radix-16 Combined Division and Square Root Unit

    DEFF Research Database (Denmark)

    Nannarelli, Alberto

    2011-01-01

    Division and square root, based on the digitrecurrence algorithm, can be implemented in a combined unit. Several implementations of combined division/square root units have been presented mostly for radices 2 and 4. Here, we present a combined radix-16 unit obtained by overlapping two radix-4...... result digit selection functions, as it is normally done for division only units. The latency of the unit is reduced by retiming and low power methods are applied as well. The proposed unit is compared to a radix-4 combined division/square root unit, and to a radix-16 unit, obtained by cascading two...

  4. Radix-16 Combined Division and Square Root Unit

    DEFF Research Database (Denmark)

    Nannarelli, Alberto

    2011-01-01

    Division and square root, based on the digitrecurrence algorithm, can be implemented in a combined unit. Several implementations of combined division/square root units have been presented mostly for radices 2 and 4. Here, we present a combined radix-16 unit obtained by overlapping two radix-4...... result digit selection functions, as it is normally done for division only units. The latency of the unit is reduced by retiming and low power methods are applied as well. The proposed unit is compared to a radix-4 combined division/square root unit, and to a radix-16 unit, obtained by cascading two...

  5. Asymmetric cell divisions: a view from plant development.

    Science.gov (United States)

    Abrash, Emily B; Bergmann, Dominique C

    2009-06-01

    All complex multicellular organisms must solve the problem of generating diverse and appropriately patterned cell types. Asymmetric division, in which a single mother cell gives rise to daughters with distinct identities, is instrumental in the generation of cellular diversity and higher-level patterns. In animal systems, there exists considerable evidence for conserved mechanisms of polarization and asymmetric division. Here, we consider asymmetric cell divisions in plants, highlighting the unique aspects of plant cell biology and organismal development that constrain the process, but also emphasizing conceptual and mechanistic similarities with animal asymmetric divisions.

  6. On Secure Two-Party Integer Division

    DEFF Research Database (Denmark)

    Dahl, Morten; Ning, Chao; Toft, Tomas

    2012-01-01

    We consider the problem of secure integer division: given two Paillier encryptions of ℓ-bit values n and d, determine an encryption of $\\lfloor \\frac{n}{d}\\rfloor$ without leaking any information about n or d. We propose two new protocols solving this problem. The first requires $\\ensuremath......{\\mathcal{O}}(\\ell)$ arithmetic operations on encrypted values (secure addition and multiplication) in $\\ensuremath{\\mathcal{O}}(1)$ rounds. This is the most efficient constant-rounds solution to date. The second protocol requires only $\\ensuremath{\\mathcal{O}} \\left( (\\log^2 \\ell)(\\kappa + \\operatorname{loglog} \\ell) \\right......)$ arithmetic operations in $\\ensuremath{\\mathcal{O}}(\\log^2 \\ell)$ rounds, where κ is a correctness parameter. Theoretically, this is the most efficient solution to date as all previous solutions have required Ω(ℓ) operations. Indeed, the fact that an o(ℓ) solution is possible at all is highly surprising....

  7. Accepting the Other: Different Division Expression

    Directory of Open Access Journals (Sweden)

    Pedro Paulo Scandiuzzi

    2010-02-01

    Full Text Available This article describes some experiences in my work close to the forest indigenous people of Brazil and these descriptions are possible because ethnomathematics´s theory is based in Paulo Freire´s method and anthropology. Gathered at an indigenous people‘s meeting point, I gave some classes on mathematics teacher pre-service education to a group of 19 people with 13 different languages. I began the didactic work with drawings and observed different drawings associated with people of different languages. This article showsrepresentational differences in the algorithm of division. The representations, combined with idiom, myth, and affect, combine to illustrate cultural influences in mathematical education. This demonstrates the need for teachers in classrooms to be aware of people of different languages and cultures. Teachers need to be sensitive and respectful of linguistic and cultural difference, and to demonstrate solidarity, cooperation, and respect towards different students. A new posture in mathematical teaching is implied.

  8. 1998 Annual Report - Environmental Restoration Division

    Energy Technology Data Exchange (ETDEWEB)

    Davis, L.B.

    1998-12-30

    This is a 1998 annual report for Environmental Restoration. Environmental Restoration's accomplishments were significant in 1998. The division, including its support organizations, completed one year without a lost time accident. It also met 111 enforceable agreement milestones on time, with more than 80% ahead of schedule. Funds used to meet these milestones were effectively utilized and $9.63 million in regulatory scope was added. Twelve new, innovative technologies were deployed, enabling ER to achieve significant progress on major field remediation projects, including: Remediation of 25 acres of radioactive burial ground; Removal of 1,300 batteries for recycling; Removal and safe storage of a radioactive underground tank; Extraction of 115,000 pounds of solvent; and Installation of 9 new recirculation wells and a second GeoSiphon Cell for additional removal of solvent Final Records of Decision were made for 9 base unit sites. No Further Action decisions were made for 61 additional sites.

  9. Division F Commission 53: Extrasolar Planets

    Science.gov (United States)

    Lecavelier Des Etangs, Alain; Minniti, Dante; Boss, Alan; Mayor, Michel; Bodenheimer, Peter; Collier-Cameron, Andrew; Jayawardhana, Ray; Kokubo, Eiichiro; Mardling, Rosemary; Queloz, Didier; Rauer, Heike; Zhao, Gang

    2016-04-01

    The IAU Working Group on Extrasolar Planets (WGESP) was created by the Executive Council as a Working Group of Division III. This decision took place in June 1999, that is only 7 years after the discovery of planets around the pulsar PSR B1257+12 and 4 years after the discovery of 51 Peg b. This working group was renewed for 3 years at the General Assembly in 2003 in Sydney, Australia. It was chaired by Alan Boss from Carnegie Institution of Washington. The WGESP members were Paul Butler, William Hubbard, Philip Ianna, Martin Kürster, Jack Lissauer, Michel Mayor, Karen Meech, Francois Mignard, Alan Penny, Andreas Quirrenbach, Jill Tarter, and Alfred Vidal-Madjar.

  10. Accepting the Other: Different Division Expression

    Directory of Open Access Journals (Sweden)

    Pedro Paulo Scandiuzzi

    2010-01-01

    Full Text Available This article describes some experiences in my work close to the forest indigenous people of Brazil and these descriptions are possible because ethnomathematics's theory is based in Paulo Freire's method and anthropology. Gathered at an indigenous people's meeting point, I gave some classes on mathematics teacher pre-service education to a group of 19 people with 13 different languages. I began the didactic work with drawings and observed different drawings associated with people of different languages. This article shows representational differences in the algorithm of division. The representations, combined with idiom, myth, and affect, combine to illustrate cultural influences in mathematical education. This demonstrates the need for teachers in classrooms to be aware of people of different languages and cultures. Teachers need to be sensitive and respectful of linguistic and cultural difference, and to demonstrate solidarity, cooperation, and respect towards different students. A new posture in mathematical teaching is implied.

  11. Biology and Medicine Division annual report, 1985

    Energy Technology Data Exchange (ETDEWEB)

    1986-04-01

    This book briefly describes the activities of the Biology and Medicine Division of the Lawrence Berkeley Laboratory. During the past year the Donner Pavilion program on the treatment of arteriovenous malformations in the brain has chalked up very significant successes. The disease control rate has been high and objective measures of success using cerebral angiography have been established. The new high resolution positron emitting tomographic imager has been demonstrated to operate successfully. In the Radiation Biophysics program, the availability of higher mass ions up to uranium has allowed us cell and tissue studies in a radiation domain that is entirely new. Using uranium beams, investigators have already made new and exciting findings that are described in the body of the report.

  12. P Division monthly report, January 1950

    Energy Technology Data Exchange (ETDEWEB)

    Lee, E.P.

    1950-02-06

    This progress report discusses the activities of the P Division for the month of January 1950. The B, D, F and H pilan operated throughout the month except for outages listed under Area Activities. Power levels were as follow: B pile -- 275 megawatts (MW) D pile -- 305 MW, F pile -- 275 MW increased to 305 MW during the month, and H pile -- 275 MW increased to 330 MW during the month. The piles operated with a time operated'' efficiency of 88.8%. A total of 53.07 tons of metal at an average of 91.2% of the current goal concentration was discharged from the piles during the month. A new record canning yield of 93.9% for 4 inch canned slugs was established during January.

  13. Scientific Scope | Division of Cancer Prevention

    Science.gov (United States)

    The Division of Cancer Prevention conducts and supports research to determine a person's risk of developing cancer and to find ways to reduce that risk. Through laboratory, clinical, and epidemiologic research, scientists have shown that the diseases of cancer occur not as single, catastrophic events, but rather as the result of a complex and long-evolving molecular process that can take decades. This long-term process of carcinogenesis provides time and opportunities to slow down, stop, or reverse the cellular changes that can become cancer. | DCP research spans the initiation of cancer and the occurrence of invasive disease in major organ sites. The overall goal is to detect changes and intervene early to prevent symptomatic disease and death.

  14. Chemical Technology Division annual technical report, 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-05-01

    Highlights of the Chemical Technology (CMT) Division's activities during 1990 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for coal- fired magnetohydrodynamics and fluidized-bed combustion; (3) methods for recovery of energy from municipal waste and techniques for treatment of hazardous organic waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for a high-level waste repository; (5) processes for separating and recovering transuranic elements from nuclear waste streams, concentrating plutonium solids in pyrochemical residues by aqueous biphase extraction, and treating natural and process waters contaminated by volatile organic compounds; (6) recovery processes for discharged fuel and the uranium blanket in the Integral Fast Reactor (IFR); (7) processes for removal of actinides in spent fuel from commercial water-cooled nuclear reactors and burnup in IFRs; and (8) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also has a program in basic chemistry research in the areas of fluid catalysis for converting small molecules to desired products; materials chemistry for superconducting oxides and associated and ordered solutions at high temperatures; interfacial processes of importance to corrosion science, high-temperature superconductivity, and catalysis; and the geochemical processes responsible for trace-element migration within the earth's crust. The Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the scientific and engineering programs at Argonne National Laboratory (ANL). 66 refs., 69 figs., 6 tabs.

  15. PENERAPAN MODEL PEMBELAJARAN KOOPERATIF TIPE STUDENT TEAMS ACHIEVEMENT DIVISION (STAD UNTUK MENINGKATKAN AKTIVITAS BELAJAR DAN HASIL BELAJAR (Kompetensi Mengidentifikasi Jenis-Jenis Surat/Dokumen Siswa Kelas XI Administrasi Perkantoran SMK Widya Praja U

    Directory of Open Access Journals (Sweden)

    Siti Umiroh

    2013-02-01

    Full Text Available Kesulitan yang dialami siswa disebabkan oleh beberapa faktor, salah satunya faktor eksternal seperti kurang tepatnya model yang diterapkan oleh guru, kesenjangan di kelas, kurangnya aktivitas siswa dan sebagainya. Hal tersebut menyebabkan perlu adanya penggunaan variasi model pembelajaran yang dapat meningkatkan aktivitas siswa dalam proses pembelajaran, salah satu alternatifnya dengan menerapkan model pembelajaran kooperatif tipe STAD. Hasil penelitian dengan menggunakan model STAD diperoleh hasil siklus I menunjukkan rata-rata hasil belajar siswa sebesar 71,22 dengan ketuntasan klasikal 60,98%, aktivitas siswa secara klasikal sebesar 60% dalam kategori cukup. Hasil penelitian siklus II menunjukkan rata-rata hasil belajar siswa sebesar 73,54 dengan ketuntasan klasikal 68,29%, aktivitas siswa secara klasikal sebesar 71,10% dalam kategori tinggi. Hasil penelitian siklus III menunjukkan rata-rata hasil belajar siswa sebesar 79,27 dengan ketuntasan klasikal 80,49%, aktivitas siswa secara klasikal sebesar 83,29% dalam kategori tinggi. Saran yang diberikan yaitu supaya siswa kelas XI AP 1 lebih aktif bertanya dalam pembelajaran di kelas serta mempunyai minat mengikuti pembelajaran khususnya pada kompetensi dasar mengidentifikasi jenis-jenis surat/dokumen. The one of factors when made students difficulties was external factor such as the inappropise model by the teacher the gapinclass, lack ofstudents activityandso on. This causes the need for the use of varied learning model which can increase the activity of students in the learning process, one of the alternatives to implement cooperative learning model STAD. The results of the study with the results obtained using the STAD model first cycle shows the average was 71.22 student learning outcomes, with classical completeness was 60.98%, in the classical student’s activitines by60% in categoryof enough. The results in cycle II study showed that the average was 73.54 student’s learning outcomes

  16. A passive optical network based on optical code division multiplexing and time division multiple access technology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A passive optical network (PON) scheme based on optical code division multiplexing (OCDM) for the downstream traffics is proposed and analyzed in detail. In the PON, the downstream traffics are broadcasted by OCDM technology to guarantee the security, while the upstream traffics pass through the same optical fiber by the common time division multiple access (TDMA) technology to decrease the cost.This schemes are denoted as OCDM/TDMA-PON, which can be applied to an optical access network (OAN) with full services on demand, such as Internet protocol, video on demand, tele-presence and high quality audio. The proposed OCDM/TDMA-PON scheme combines advantages of PON, TDMA, and OCDM technology. Simulation results indicate that the designed scheme improves the OAN performance,and enhances flexibility and scalability of the system.

  17. Enterprise virtual private network (VPN) with dense wavelength division multiplexing (DWDM) design

    Science.gov (United States)

    Carranza, Aparicio

    An innovative computer simulation and modeling tool for metropolitan area optical data communication networks is presented. These models address the unique requirements of Virtual Private Networks for enterprise data centers, which may comprise a mixture of protocols including ESCON, FICON, Fibre Channel, Sysplex protocols (ETR, CLO, ISC); and other links interconnected over dark fiber using Dense Wavelength Division Multiplexing (DWDM). Our models have the capability of designing a network with minimal inputs; to compute optical link budgets; suggest alternative configurations; and also optimize the design based on user-defined performance metrics. The models make use of Time Division Multiplexing (TDM) wherever possible for lower data rate traffics. Simulation results for several configurations are presented and they have been validated by means of experiments conducted on the IBM enterprise network testbed in Poughkeepsie, N.Y.

  18. Polarity, cell division, and out-of-equilibrium dynamics control the growth of epithelial structures

    Science.gov (United States)

    Cerruti, Benedetta; Puliafito, Alberto; Shewan, Annette M.; Yu, Wei; Combes, Alexander N.; Little, Melissa H.; Chianale, Federica; Primo, Luca; Serini, Guido; Mostov, Keith E.; Celani, Antonio

    2013-01-01

    The growth of a well-formed epithelial structure is governed by mechanical constraints, cellular apico-basal polarity, and spatially controlled cell division. Here we compared the predictions of a mathematical model of epithelial growth with the morphological analysis of 3D epithelial structures. In both in vitro cyst models and in developing epithelial structures in vivo, epithelial growth could take place close to or far from mechanical equilibrium, and was determined by the hierarchy of time-scales of cell division, cell–cell rearrangements, and lumen dynamics. Equilibrium properties could be inferred by the analysis of cell–cell contact topologies, and the nonequilibrium phenotype was altered by inhibiting ROCK activity. The occurrence of an aberrant multilumen phenotype was linked to fast nonequilibrium growth, even when geometric control of cell division was correctly enforced. We predicted and verified experimentally that slowing down cell division partially rescued a multilumen phenotype induced by altered polarity. These results improve our understanding of the development of epithelial organs and, ultimately, of carcinogenesis. PMID:24145168

  19. The Synchronization of Replication and Division Cycles in Individual E. coli Cells.

    Science.gov (United States)

    Wallden, Mats; Fange, David; Lundius, Ebba Gregorsson; Baltekin, Özden; Elf, Johan

    2016-07-28

    Isogenic E. coli cells growing in a constant environment display significant variability in growth rates, division sizes, and generation times. The guiding principle appears to be that each cell, during one generation, adds a size increment that is uncorrelated to its birth size. Here, we investigate the mechanisms underlying this "adder" behavior by mapping the chromosome replication cycle to the division cycle of individual cells using fluorescence microscopy. We have found that initiation of chromosome replication is triggered at a fixed volume per chromosome independent of a cell's birth volume and growth rate. Each initiation event is coupled to a division event after a growth-rate-dependent time. We formalize our findings in a model showing that cell-to-cell variation in division timing and cell size is mainly driven by variations in growth rate. The model also explains why fast-growing cells display adder behavior and correctly predict deviations from the adder behavior at slow growth. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Division site positioning in bacteria: one size does not fit all.

    Directory of Open Access Journals (Sweden)

    Leigh Graham Monahan

    2014-02-01

    Full Text Available Spatial regulation of cell division in bacteria has been a focus of research for decades. It has been well studied in two model rod-shaped organisms, Escherichia coli and Bacillus subtilis, with the general belief that division site positioning occurs as a result of the combination of two negative regulatory systems, Min and nucleoid occlusion. These systems influence division by preventing the cytokinetic Z ring from forming anywhere other than midcell. However, evidence is accumulating for the existence of additional mechanisms that are involved in controlling Z ring positioning both in these organisms and in several other bacteria. In some cases the decision of where to divide is solved by variations on a common evolutionary theme, and in others completely different proteins and mechanisms are involved. Here we review the different ways bacteria solve the problem of finding the right place to divide. It appears that a one-size-fits-all model does not apply, and that individual species have adapted a division-site positioning mechanism that best suits their lifestyle, environmental niche and mode of growth to ensure equal partitioning of DNA for survival of the next generation.

  1. The PLASTID DIVISION1 and 2 Components of the Chloroplast Division Machinery Determine the Rate of Chloroplast Division in Land Plant Cell Differentiation

    National Research Council Canada - National Science Library

    Kumiko Okazaki; Yukihiro Kabeya; Kenji Suzuki; Toshiyuki Mori; Takanari Ichikawa; Minami Matsui; Hiromitsu Nakanishi; Shin-Ya Miyagishima

    2009-01-01

    .... By contrast, land plants evolved cell and chloroplast differentiation systems in which the size and number of chloroplasts change along with their respective cellular function by regulation of the division rate...

  2. Orange You Glad I "Did" Say "Fraction Division"?

    Science.gov (United States)

    Flores, Alfinio; Priewe, Melina D.

    2013-01-01

    This article describes how teachers address issues and tensions that students meet in learning division of fractions. First, students must make sense of division of fractions on their own by working individually and in small groups, using concrete or pictorial representations, inventing their own processes, and presenting and justifying their…

  3. The Division of Chemical Education Revisited, 25 Years Later

    Science.gov (United States)

    Bodner, George M.; Towns, Marcy H.

    2010-01-01

    This paper examines what has happened over a period of 25 years since a separate Division of Chemical Education was created within the Department of Chemistry at Purdue University. It argues that the faith in the chemical education graduate program that was demonstrated when the division was created was well-placed, and that chemical education has…

  4. Earth Sciences Division, collected abstracts-1977. [Research programs

    Energy Technology Data Exchange (ETDEWEB)

    Quitiquit, W.A.; Ledbetter, G.P.; Henry, A.L.

    1978-05-24

    This report is a compilation of abstracts of papers, internal reports, and talks presented during 1977 at national and international meetings by members of the Earth Sciences Division, Lawrence Livermore Laboratory. It is arranged alphabetically by author and includes a cross-reference by subject indicating the areas of research interest of the Earth Sciences Division.

  5. The marital dynamics of conflict over the division of labor

    NARCIS (Netherlands)

    Kluwer, E.S.; Heesink, J.A.M.; Van de Vliert, E.

    1997-01-01

    The division of labor as a source of conflict is a concern for many couples. This study goes beyond the mere prediction of the amount of marital conflict by scrutinizing the relationship between spouses' discontent with the division of labor, their conflict interaction patterns, and subsequent outco

  6. Control of nuclear division by the Chromosomal Passenger Complex

    NARCIS (Netherlands)

    van der Waal, M.S.

    2012-01-01

    Most cells within an organism function while they are in a non-dividing state. Cells enter the division cycle to initiate tissue growth or to repair damaged tissue. In the last phase of this cycle, M-phase, cytoplasmic division (cytokinesis) is accomplished after, in case of dividing human cells, 23

  7. The marital dynamics of conflict over the division of labor

    NARCIS (Netherlands)

    Kluwer, E.S.; Heesink, J.A.M.; Van de Vliert, E.

    1997-01-01

    The division of labor as a source of conflict is a concern for many couples. This study goes beyond the mere prediction of the amount of marital conflict by scrutinizing the relationship between spouses' discontent with the division of labor, their conflict interaction patterns, and subsequent outco

  8. Spindle Positioning and Cell Division in Caenorhabditis elegans

    NARCIS (Netherlands)

    Voet, M. van der

    2010-01-01

    During cell division a cell duplicates its genetic material and segregates one intact copy into each daughter cell. However, cell division has many aspects in addition to the propagation of the genome. For instance, some cells divide asymmetrically, which contributes to the generation of cell

  9. Plant cortical microtubule dynamics and cell division plane orientation

    NARCIS (Netherlands)

    Chakrabortty, Bandan

    2017-01-01

    This thesis work aimed at a better understanding of the molecular basis of oriented cell division in plant cell. As, the efficiency of plant morphogenesis depends on oriented cell division, this work should contribute  towards a fundamental understanding of the  molecular basis of

  10. 5 CFR 842.613 - Division of a survivor annuity.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Division of a survivor annuity. 842.613... REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Survivor Elections § 842.613 Division of a survivor annuity. (a) The maximum combined total of all current and former spouse...

  11. 5 CFR 831.641 - Division of a survivor annuity.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Division of a survivor annuity. 831.641... REGULATIONS (CONTINUED) RETIREMENT Survivor Annuities Eligibility § 831.641 Division of a survivor annuity. (a... comply with a court order under subpart Q, a survivor annuity may be divided into a combination of...

  12. Subtidal flow division at a shallow tidal junction

    NARCIS (Netherlands)

    Buschman, F.A.; Hoitink, A.J.F.; Vegt, van der M.; Hoekstra, P.

    2010-01-01

    Tides influence distribution of river discharge at tidally affected channel junctions. At the apex of a channel network in an Indonesian delta, observations of flow division suggest that tidally averaged flow division depends on the tidal range. To understand the mechanisms governing the subtidal fl

  13. High energy physics division semiannual report of research activities

    Energy Technology Data Exchange (ETDEWEB)

    Schoessow, P.; Moonier, P.; Talaga, R.; Wagner, R. (eds.) (Argonne National Lab., IL (United States))

    1991-08-01

    This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of January 1, 1991--June 30, 1991. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of division publications and colloquia are included.

  14. THE WESTERN ECOLOGY DIVISION STUDENT INTERN PROGRAM VIDEO

    Science.gov (United States)

    The Western Ecology Division of the National Health & Environmental Effects Research Laboratory has produced a 15 minute video documenting the internship program at the Division. The video highlights various CWEST student interns reporting on their experiences at an end-of-the-s...

  15. Ploidy-Dependent Unreductional Meiotic Cell Division in Polyploid Wheat

    Science.gov (United States)

    Meiosis includes one round of DNA replication and two successive nuclear divisions, i.e. meiosis I (reductional) and meiosis II (equational). This specialized cell division reduces chromosomes in half and generates haploid gametes in sexual reproduction of eukaryotes. It ensures faithful transmiss...

  16. High-precision, wavelength flexible frequency division for metrology

    NARCIS (Netherlands)

    Gross, Petra; Klein, Marvin E.; Boller, Klaus-Jochen

    2005-01-01

    We realize and investigate wavelength-flexible phase-coherent all-optical frequency division by 2. Frequency division is obtained via self-phase-locking in a degenerate continuous-wave (cw) optical parametric oscillator (OPO). The wavelength flexibility of the divider is based on the use of quasi-ph

  17. 28 CFR 16.76 - Exemption of Justice Management Division.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Exemption of Justice Management Division. 16.76 Section 16.76 Judicial Administration DEPARTMENT OF JUSTICE PRODUCTION OR DISCLOSURE OF... Management Division. (a) The following system of records is exempt from 5 U.S.C. 552a(d): (1)...

  18. The History of the Southwestern Division, 1986-1994

    Science.gov (United States)

    1997-01-01

    of layoff or transfer. No district or division The Sante Fe Building, downtown Dallas, remains the headquarters of the Southwestern Division. 85...Oklahoma,2,3,4, 73, 75 National Aeronautics and Space Administration ( NASA ), 9 National Environmental Protection Act (NEPA), 9, 31 National ~arine

  19. Nuclear Science Division, 1995--1996 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Poskanzer, A.M. [ed.

    1997-02-01

    This report describes the activities of the Nuclear Science Division (NSD) for the two-year period, January 1, 1995 to January 1, 1997. This was a time of major accomplishments for all research programs in the Division-many of which are highlighted in the reports of this document.

  20. Spindle Positioning and Cell Division in Caenorhabditis elegans

    NARCIS (Netherlands)

    Voet, M. van der

    2010-01-01

    During cell division a cell duplicates its genetic material and segregates one intact copy into each daughter cell. However, cell division has many aspects in addition to the propagation of the genome. For instance, some cells divide asymmetrically, which contributes to the generation of cell divers

  1. LOCAL INSTRUCTION THEORY ON DIVISION IN MATHEMATICS GASING

    Directory of Open Access Journals (Sweden)

    Rully Charitas Indra Prahmana

    2014-01-01

    Full Text Available Several studies on learning mathematics for rural area's student indicate that students have difficulty in understanding the concept of division operation. Students are more likely to be introduced by the use of the formula without involving the concept itself and learning division separate the concrete situation of learning process. This underlies the researcher to design division operation learning in the Mathematics of GASING (Math GASING, which always starts from concrete to abstract level. The research method used is a design research which describes how the Math GASING make a real contribution of students understanding in the concept of division operation. Keywords: Division Operation, Design Research, Math GASING, Rural Area’s Student DOI: http://dx.doi.org/10.22342/jme.5.1.1445.17-26

  2. Asymmetric division coordinates collective cell migration in angiogenesis.

    Science.gov (United States)

    Costa, Guilherme; Harrington, Kyle I; Lovegrove, Holly E; Page, Donna J; Chakravartula, Shilpa; Bentley, Katie; Herbert, Shane P

    2016-12-01

    The asymmetric division of stem or progenitor cells generates daughters with distinct fates and regulates cell diversity during tissue morphogenesis. However, roles for asymmetric division in other more dynamic morphogenetic processes, such as cell migration, have not previously been described. Here we combine zebrafish in vivo experimental and computational approaches to reveal that heterogeneity introduced by asymmetric division generates multicellular polarity that drives coordinated collective cell migration in angiogenesis. We find that asymmetric positioning of the mitotic spindle during endothelial tip cell division generates daughters of distinct size with discrete 'tip' or 'stalk' thresholds of pro-migratory Vegfr signalling. Consequently, post-mitotic Vegfr asymmetry drives Dll4/Notch-independent self-organization of daughters into leading tip or trailing stalk cells, and disruption of asymmetry randomizes daughter tip/stalk selection. Thus, asymmetric division seamlessly integrates cell proliferation with collective migration, and, as such, may facilitate growth of other collectively migrating tissues during development, regeneration and cancer invasion.

  3. A Toxoplasma MORN1 null mutant undergoes repeated divisions but is defective in basal assembly, apicoplast division and cytokinesis.

    Directory of Open Access Journals (Sweden)

    Alexander Lorestani

    Full Text Available The membrane occupation and recognition nexus protein 1 (MORN1 is highly conserved among apicomplexan parasites and is associated with several structures that have a role in cell division. Here we dissected the role of MORN1 using the relatively simple budding process of Toxoplasma gondii as a model. Ablation of MORN1 in a conditional null mutant resulted in pronounced defects suggesting a central role for MORN1 in apicoplast segregation and in daughter cell budding. Lack of MORN1 resulted in double-headed parasites. These Janus-headed parasites form two complete apical complexes but fail to assemble a basal complex. Moreover, these parasites were capable of undergoing several more budding rounds resulting in the formation of up to 16-headed parasites conjoined at the basal end. Despite this segregation defect, the mother's cytoskeleton was completely disassembled in every budding round. Overall this argues that successful completion of the budding is not required for cell cycle progression. None of the known basal complex components, including a set of recently identified inner membrane complex (IMC proteins, localized correctly in these multi-headed parasites. These data suggest that MORN1 is essential for assembly of the basal complex, and that lack of the basal complex abolishes the contractile capacity assigned to the basal complex late in daughter formation. Consistent with this hypothesis we observe that MORN1 mutants fail to efficiently constrict and divide the apicoplast. We used the null background provided by the mutant to dissect the function of subdomains of the MORN1 protein. This demonstrated that deletion of a single MORN domain already prevented the function of MORN1 whereas a critical role for the short linker between MORN domains 6 and 7 was identified. In conclusion, MORN1 is required for basal complex assembly and loss of MORN1 results in defects in apicoplast division and daughter segregation.

  4. How bacterial cell division might cheat turgor pressure - a unified mechanism of septal division in Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Erickson, Harold P

    2017-08-01

    An important question for bacterial cell division is how the invaginating septum can overcome the turgor force generated by the high osmolarity of the cytoplasm. I suggest that it may not need to. Several studies in Gram-negative bacteria have shown that the periplasm is isoosmolar with the cytoplasm. Indirect evidence suggests that this is also true for Gram-positive bacteria. In this case the invagination of the septum takes place within the uniformly high osmotic pressure environment, and does not have to fight turgor pressure. A related question is how the V-shaped constriction of Gram-negative bacteria relates to the plate-like septum of Gram-positive bacteria. I collected evidence that Gram-negative bacteria have a latent capability of forming plate-like septa, and present a model in which septal division is the basic mechanism in both Gram-positive and Gram-negative bacteria. © 2017 WILEY Periodicals, Inc.

  5. 基于技术扩散模型的区域"数字鸿沟"演变阶段划分%A Division to Evolution Stages of "Digital Divide" between Regions Based on Technology Diffusion Model

    Institute of Scientific and Technical Information of China (English)

    薛伟贤; 刘骏

    2011-01-01

    Firstly, " ICTs diffusion model" is established based on classical technology diffusion model, and time path function of diffusion is derived from the model. By the method of depicting graph, the graph of time path function shows itself as S-Curve pattern. After that , "digital divide" between regions is shown through difference of two region's time path functions. And on this basis evolution stages of "digital divide" between regions are divided. The research result shows that the internal and external factors , number of " potential user" , the number of initial user in different regions are discrepant,so time path functions of different regions are diverse, and difference of diverse time path functions indicates " digital divide" between regions. Therefore, evolution of "digital divide " between regions is divided into three stages : the gradual expansion stage, the stabilization stage, the gradual reducing stage. This research theoretically reveals the evolution rule of " digital divide " between regions.%基于经典的技术扩散模型,构建了"ICTs的扩散模型",在模型中推导出ICTs扩散的时间路径函数,通过函数图形描绘发现其图形是S形曲线,然后用两个地区的时间路径函数之差表示出区域"数字鸿沟",在此基础上对区域"数字鸿沟"演变的阶段进行划分.研究结果表明,由于不同地区内外部因素、"潜在采纳者"总数、最初使用者数量存在差异,导致不同地区ICTs扩散的时间路径函数不同,从而表现出区域"数字鸿沟",其演变可划分为逐渐扩大阶段、稳定阶段、逐渐缩小阶段.本文从理论上揭示了区域"数字鸿沟"的演变规律.

  6. Role of the Number of Microtubules in Chromosome Segregation during Cell Division

    CERN Document Server

    Bertalan, Zsolt; La Porta, Caterina A M; Zapperi, Stefano

    2015-01-01

    Faithful segregation of genetic material during cell division requires alignment of chromosomes between two spindle poles and attachment of their kinetochores to each of the poles. Failure of these complex dynamical processes leads to chromosomal instability (CIN), a characteristic feature of several diseases including cancer. While a multitude of biological factors regulating chromosome congression and bi-orientation have been identified, it is still unclear how they are integrated so that coherent chromosome motion emerges from a large collection of random and deterministic processes. Here we address this issue by a three dimensional computational model of motor-driven chromosome congression and bi-orientation during mitosis. Our model reveals that successful cell division requires control of the total number of microtubules: if this number is too small bi-orientation fails, while if it is too large not all the chromosomes are able to congress. The optimal number of microtubules predicted by our model compa...

  7. Chemical Technology Division annual technical report, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Battles, J.E.; Myles, K.M.; Laidler, J.J.; Green, D.W.

    1993-06-01

    In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion and coal-fired magnetohydrodynamics; (3) methods for treatment of hazardous waste, mixed hazardous/radioactive waste, and municipal solid waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (5) processes for separating and recovering transuranic elements from nuclear waste streams, treating water contaminated with volatile organics, and concentrating radioactive waste streams; (6) recovery processes for discharged fuel and the uranium blanket in the Integral Fast Reactor (EFR); (7) processes for removal of actinides in spent fuel from commercial water-cooled nuclear reactors and burnup in IFRs; and (8) physical chemistry of selected materials (corium; Fe-U-Zr, tritium in LiAlO{sub 2} in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources and novel` ceramic precursors; materials chemistry of superconducting oxides, electrified metal/solution interfaces, and molecular sieve structures; and the geochemical processes involved in water-rock interactions occurring in active hydrothermal systems. In addition, the Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the technical programs at Argonne National Laboratory (ANL).

  8. The Architecture of the Cassini Division

    CERN Document Server

    Hedman, M M; Baines, K; Buratti, B; Sotin, C; Clark, R N; Brown, R H; French, R; Marouf, E

    2009-01-01

    The Cassini Division in Saturn's rings contains a series of eight named gaps, three of which contain dense ringlets. Observations of stellar occultations by the Visual and Infrared Mapping Spectrometer onboard the Cassini spacecraft have yielded ~40 accurate and precise measurements of the radial position of the edges of all of these gaps and ringlets. These data reveal suggestive patterns in the shapes of many of the gap edges: the outer edges of the 5 gaps without ringlets are circular to within 1 km, while the inner edges of 6 of the gaps are eccentric, with apsidal precession rates consistent with those expected for eccentric orbits near each edge. Intriguingly, the pattern speeds of these eccentric inner gap edges, together with that of the eccentric Huygens ringlet,form a series with a characteristic spacing of 0.06 degrees/day. The two gaps with non-eccentric inner edges lie near first-order Inner Lindblad Resonances (ILRs) with moons. One such edge is close to the 5:4 ILR with Prometheus. The other re...

  9. Novel coiled-coil cell division factor ZapB stimulates Z ring assembly and cell division

    DEFF Research Database (Denmark)

    Ebersbach, Gitte; Galli, Elisa; Møller-Jensen, Jakob;

    2008-01-01

    Formation of the Z ring is the first known event in bacterial cell division. However, it is not yet known how the assembly and contraction of the Z ring are regulated. Here, we identify a novel cell division factor ZapB in Escherichia coli that simultaneously stimulates Z ring assembly and cell...

  10. Traffic Analysis Zones, This Layer was created by ARC's Transportation Planning Division to identify Traffic Analysis Zones (TAZs) in the 20-county Atlanta Region. These TAZs represent the geography used in the ongoing transportation modeling for the Envision 6 forecast series (, Published in 2006, 1:100000 (1in=8333ft) scale, Atlanta Regional Commission.

    Data.gov (United States)

    NSGIC Regional | GIS Inventory — Traffic Analysis Zones dataset current as of 2006. This Layer was created by ARC's Transportation Planning Division to identify Traffic Analysis Zones (TAZs) in the...

  11. Algebres non associatives normees de division. Classification des algebres reelles de Jordan non commutatives de division lineaire de dimension 8

    CERN Document Server

    Rochdi, Abdellatif

    2010-01-01

    In this work we are interested in the general problem of the determination of the normed division algebras. Our fundamental results are obtained in the particular subclass of those 8-dimensional quadratic flexible real division algebras. We give a new process which generalizes that of Cayley-Dickson and which allows the obtaining of a new family of eight-dimensional quadratic flexible real division algebras. We give examples of 8-dimensional quadratic flexible real division algebras which cannot be obtained by this first process of duplication and by means of a second process, which consists in making an appropriate deformation of the product of the octonion algebra, we determine these last ones and we resolve the isomorphism problem. Among the eight-dimensional quadratic flexible real division algebras, we study those which possess a nontrivial derivation by mean of the generalized Cayley-Dickson process. We also give examples where the group of automorphisms is trivial, and characterize the algebras whose g...

  12. Dissection of Cell Division Processes in the One Cell Stage Caenorhabditis elegans Embryo by Mutational Analysis

    Science.gov (United States)

    Gönczy, Pierre; Schnabel, Heinke; Kaletta, Titus; Amores, Ana Duran; Hyman, Tony; Schnabel, Ralf

    1999-01-01

    To identify novel components required for cell division processes in complex eukaryotes, we have undertaken an extensive mutational analysis in the one cell stage Caenorhabditis elegans embryo. The large size and optical properties of this cell permit observation of cell division processes with great detail in live specimens by simple differential interference contrast (DIC) microscopy. We have screened an extensive collection of maternal-effect embryonic lethal mutations on chromosome III with time-lapse DIC video microscopy. Using this assay, we have identified 48 mutations in 34 loci which are required for specific cell division processes in the one cell stage embryo. We show that mutations fall into distinct phenotypic classes which correspond, among others, to the processes of pronuclear migration, rotation of centrosomes and associated pronuclei, spindle assembly, chromosome segregation, anaphase spindle positioning, and cytokinesis. We have further analyzed pronuclear migration mutants by indirect immunofluorescence microscopy using antibodies against tubulin and ZYG-9, a centrosomal marker. This analysis revealed that two pronuclear migration loci are required for generating normal microtubule arrays and four for centrosome separation. All 34 loci have been mapped by deficiencies to distinct regions of chromosome III, thus paving the way for their rapid molecular characterization. Our work contributes to establishing the one cell stage C. elegans embryo as a powerful metazoan model system for dissecting cell division processes. PMID:10085292

  13. Physics, Computer Science and Mathematics Division. Annual report, 1 January--31 December 1977. [LBL, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Lepore, J.V. (ed.)

    1977-01-01

    This annual report of the Physics, Computer Science and Mathematics Division describes the scientific research and other work carried out within the Division during 1977. The Division is concerned with work in experimental and theoretical physics, with computer science and applied mathematics, and with the operation of a computer center. The major physics research activity is in high-energy physics, although there is a relatively small program of medium-energy research. The High Energy Physics research program in the Physics Division is concerned with fundamental research which will enable man to comprehend the nature of the physical world. The major effort is now directed toward experiments with positron-electron colliding beam at PEP. The Medium Energy Physics program is concerned with research using mesons and nucleons to probe the properties of matter. This research is concerned with the study of nuclear structure, nuclear reactions, and the interactions between nuclei and electromagnetic radiation and mesons. The Computer Science and Applied Mathematics Department engages in research in a variety of computer science and mathematics disciplines. Work in computer science and applied mathematics includes construction of data bases, computer graphics, computational physics and data analysis, mathematical modeling, and mathematical analysis of differential and integral equations resulting from physical problems. The Computer Center provides large-scale computational support to LBL's scientific programs. Descriptions of the various activities are quite short; references to published results are given. 24 figures. (RWR)

  14. Spire, an actin nucleation factor, regulates cell division during Drosophila heart development.

    Directory of Open Access Journals (Sweden)

    Peng Xu

    Full Text Available The Drosophila dorsal vessel is a beneficial model system for studying the regulation of early heart development. Spire (Spir, an actin-nucleation factor, regulates actin dynamics in many developmental processes, such as cell shape determination, intracellular transport, and locomotion. Through protein expression pattern analysis, we demonstrate that the absence of spir function affects cell division in Myocyte enhancer factor 2-, Tinman (Tin-, Even-skipped- and Seven up (Svp-positive heart cells. In addition, genetic interaction analysis shows that spir functionally interacts with Dorsocross, tin, and pannier to properly specify the cardiac fate. Furthermore, through visualization of double heterozygous embryos, we determines that spir cooperates with CycA for heart cell specification and division. Finally, when comparing the spir mutant phenotype with that of a CycA mutant, the results suggest that most Svp-positive progenitors in spir mutant embryos cannot undergo full cell division at cell cycle 15, and that Tin-positive progenitors are arrested at cell cycle 16 as double-nucleated cells. We conclude that Spir plays a crucial role in controlling dorsal vessel formation and has a function in cell division during heart tube morphogenesis.

  15. Force generation by a dynamic Z-ring in Escherichia coli cell division.

    Science.gov (United States)

    Allard, Jun F; Cytrynbaum, Eric N

    2009-01-06

    FtsZ, a bacterial homologue of tubulin, plays a central role in bacterial cell division. It is the first of many proteins recruited to the division site to form the Z-ring, a dynamic structure that recycles on the time scale of seconds and is required for division to proceed. FtsZ has been recently shown to form rings inside tubular liposomes and to constrict the liposome membrane without the presence of other proteins, particularly molecular motors that appear to be absent from the bacterial proteome. Here, we propose a mathematical model for the dynamic turnover of the Z-ring and for its ability to generate a constriction force. Force generation is assumed to derive from GTP hydrolysis, which is known to induce curvature in FtsZ filaments. We find that this transition to a curved state is capable of generating a sufficient force to drive cell-wall invagination in vivo and can also explain the constriction seen in the in vitro liposome experiments. Our observations resolve the question of how FtsZ might accomplish cell division despite the highly dynamic nature of the Z-ring and the lack of molecular motors.

  16. 49 CFR 173.244 - Bulk packaging for certain pyrophoric liquids (Division 4.2), dangerous when wet (Division 4.3...

    Science.gov (United States)

    2010-10-01

    ... (Division 4.2), dangerous when wet (Division 4.3) materials, and poisonous liquids with inhalation hazards (Division 6.1). 173.244 Section 173.244 Transportation Other Regulations Relating to Transportation PIPELINE... Other Than Class 1 and Class 7 § 173.244 Bulk packaging for certain pyrophoric liquids (Division...

  17. Energy Division progress report, fiscal years 1994--1995

    Energy Technology Data Exchange (ETDEWEB)

    Moser, C.I. [ed.

    1996-06-01

    At ORNL, the Energy Division`s mission is to provide innovative solutions to energy and related issues of national and global importance through interdisciplinary research and development. Its goals and accomplishments are described in this progress report for FY 1994 and FY 1995. The Division`s expenditures in FY 1995 totaled 44.9 million. Sixty percent of the divisions work was supported by the US DOE. Other significant sponsors include the US DOT, the US DOD, other federal agencies, and some private organizations. The Division`s programmatic activities cover three main areas: (1) analysis and assessment, (2) transportation systems, and (3) energy use and delivery technologies. Analysis and assessment activities involve energy and resource analysis, preparation of environmental assessments and impact statements, and impact statements, research on emergency preparedness, analysis of energy and environmental needs in developing countries, and transportation analysis. Transportation systems research seeks to improve the quality of both civilian and military transportation efforts. Energy use and delivery technologies focus on building equipment, building envelopes, (walls, roofs, attics, and materials), improvement of energy efficiency in buildings, and electric power systems.

  18. Maximum Entropy for the International Division of Labor.

    Science.gov (United States)

    Lei, Hongmei; Chen, Ying; Li, Ruiqi; He, Deli; Zhang, Jiang

    2015-01-01

    As a result of the international division of labor, the trade value distribution on different products substantiated by international trade flows can be regarded as one country's strategy for competition. According to the empirical data of trade flows, countries may spend a large fraction of export values on ubiquitous and competitive products. Meanwhile, countries may also diversify their exports share on different types of products to reduce the risk. In this paper, we report that the export share distribution curves can be derived by maximizing the entropy of shares on different products under the product's complexity constraint once the international market structure (the country-product bipartite network) is given. Therefore, a maximum entropy model provides a good fit to empirical data. The empirical data is consistent with maximum entropy subject to a constraint on the expected value of the product complexity for each country. One country's strategy is mainly determined by the types of products this country can export. In addition, our model is able to fit the empirical export share distribution curves of nearly every country very well by tuning only one parameter.

  19. CSIR Division of Mining Technology annual review 1993/94

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    The Division of Mining Technology of the CSIR (Council for Scientific and Industrial Research) works in partnership with the mining industry to solve problems threatening the health, safety and well-being of the workforce, and the productivity of mining operations through the development and implementation of knowledge and technology. The annual review describes the Division's research projects in the following field: rock engineering (for gold, platinum and coal mining); mining environment; occupational hygiene; surface environment; and mining equipment and systems (systems and equipment, orebody information, coal mining and causes of accidents). Details are also given of the Division's publications, research and consultancy services and information centre.

  20. Mechanisms of asymmetric cell divisions in Drosophila melanogaster neuroblasts

    Directory of Open Access Journals (Sweden)

    X Jiang

    2014-04-01

    Full Text Available Stem cells possess the properties of self-renewal and differentiation, and mainly rely on two strategies for division, including symmetric and asymmetric cell divisions. In this review, we summarize the latest progress on asymmetric cell divisions in Drosophila melanogaster neuroblasts (NBs, which focus on the establishment of cell polarity, mitotic spindle orientation, the asymmetric segregation of cell fate determinants as well as cell-cycle control. Here we also introduce five major cell fate determinants, including Numb, Prospero, Brat, Miranda, and Pon, which are thought to be unequally segregated to the ganglion mother cells (GMCs and play an important role in the formation of stem cell-derived tumors

  1. Mitochondrial inheritance is mediated by microtubules in mammalian cell division.

    Science.gov (United States)

    Lawrence, Elizabeth; Mandato, Craig

    2013-11-01

    The mitochondrial network fragments and becomes uniformly dispersed within the cytoplasm when mammalian cells enter mitosis. Such morphology and distribution of mitochondria was previously thought to facilitate the stochastic inheritance of mitochondria by daughter cells. In contrast, we recently reported that mitochondria in dividing mammalian cells are inherited by an ordered mechanism of inheritance mediated by microtubules. We showed that mitochondria are progressively enriched at the cell equator and depleted at the poles throughout division. Furthermore, the mitochondrial distribution during division is dependent on microtubules, indicating an ordered inheritance strategy. The microtubule-mediated positioning of mitochondria in dividing mammalian cells may have functional consequences for cell division and/or mitochondrial inheritance.

  2. Environmental Research Division technical progress report: January 1986--October 1987

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-01

    Technical process in the various research activities of Argonne National Laboratory's Environmental Research Division is reported for the period 1986-1987. Textual, graphic, and tabular information is used to briefly summarize (in separate chapters) the work of the Division's Atmospheric Physics, Environmental Effects Research, Fundamental Molecular Physics and Chemistry, and Organic Geochemistry and Environmental Instrumentation Programs. Information on professional qualifications, awards, and outstanding professional activities of staff members, as well as lists of publications, oral presentations, special events organized, and participants in educational programs, are provided in appendices at the end of each chapter. Individual projects under each division are processed separately for the data bases.

  3. Reasonable partiality in professional ethics: the moral division of labour.

    Science.gov (United States)

    Jacobs, Frans

    2005-04-01

    Attention is given to a background idea that is often invoked in discussions about reasonable partiality: the idea of a moral division of labour. It is not only a right, but also a duty for professionals to attend (almost) exclusively to the interests of their own clients, because their partial activities are part of an impartial scheme providing for an allocation of professional help to all clients. To clarify that idea, a difference is made between two kinds of division of labour, a technical one and a social one. In order to assess the applicability of the idea of a moral division of labour to professional ethics, journalism is contrasted with other professions.

  4. Indole prevents Escherichia coli cell division by modulating membrane potential

    OpenAIRE

    Chimerel, Catalin; Field, Christopher M.; Piñero-Fernandez, Silvia; Keyser, Ulrich F.; Summers, David K.

    2012-01-01

    Indole is a bacterial signalling molecule that blocks E. coli cell division at concentrations of 3–5 mM. We have shown that indole is a proton ionophore and that this activity is key to the inhibition of division. By reducing the electrochemical potential across the cytoplasmic membrane of E. coli, indole deactivates MinCD oscillation and prevents formation of the FtsZ ring that is a prerequisite for division. This is the first example of a natural ionophore regulating a key biological proces...

  5. Asymptotic behavior of a nonlinear functional-integral equation of cell kinetics with unequal division.

    Science.gov (United States)

    Arino, O; Kimmel, M

    1989-01-01

    A model of cell cycle kinetics is proposed, which includes unequal division of cells, and a nonlinear dependence of the fraction of cells re-entering proliferation on the total number of cells in the cycle. The model is described by a nonlinear functional-integral equation. It is analyzed using the operator semigroup theory combined with classical differential equations approach. A complete description of the asymptotic behavior of the model is provided for a relatively broad class of nonlinearities. The nonnegative solutions either tend to a stable steady state, or to zero. The simplicity of the model makes it an interesting step in the analysis of dynamics of nonlinear structure populations.

  6. 77 FR 4368 - Abbott Laboratories, Diagnostics Division, Including On-Site Leased Workers From Manpower...

    Science.gov (United States)

    2012-01-27

    ... Employment and Training Administration Abbott Laboratories, Diagnostics Division, Including On-Site Leased..., Diagnostics Division, including on-site leased workers from Manpower, Comsys, Apex, Fountain Group, Kelly... location of Abbott Laboratories, Diagnostics Division. The Department has determined that these...

  7. 78 FR 1265 - Dana Holding Corporation; Power Technologies Group Division; Including On-Site Leased Workers...

    Science.gov (United States)

    2013-01-08

    ... Employment and Training Administration Dana Holding Corporation; Power Technologies Group Division; Including... Technologies Group Division, Milwaukee, Wisconsin (subject firm). The worker group includes on-site leased... Company, Power Technologies Group Division, Milwaukee, Wisconsin, who were engaged in employment...

  8. Completion of cell division is associated with maximum telomerase activity in naturally synchronized cultures of the green alga Desmodesmus quadricauda.

    Science.gov (United States)

    Ševčíková, Tereza; Bišová, Kateřina; Fojtová, Miloslava; Lukešová, Alena; Hrčková, Kristýna; Sýkorová, Eva

    2013-03-18

    Telomerase maintains the ends of eukaryotic chromosomes, and its activity is an important parameter correlating with the proliferative capacity of cells. We have investigated cell cycle-specific changes in telomerase activity using cultures of Desmodesmus quadricauda, a model alga naturally synchronized by light/dark entrainment. A quantitative telomerase assay revealed high activity in algal cultures, with slight changes during the light period. Significantly increased telomerase activity was observed at the end of the dark phase, when cell division was complete. In contrast to other models, a natural separation between nuclear and cellular division typical for the cell cycle in D. quadricauda made this observation possible.

  9. Arabidopsis FRS4/CPD25 and FHY3/CPD45 work cooperatively to promote the expression of the chloroplast division gene ARC5 and chloroplast division.

    Science.gov (United States)

    Gao, Yuefang; Liu, Han; An, Chuanjing; Shi, Yuhong; Liu, Xia; Yuan, Wanqiong; Zhang, Bing; Yang, Jin; Yu, Caixia; Gao, Hongbo

    2013-09-01

    ARC5 is a dynamin-related GTPase essential for the division of chloroplasts in plants. The arc5 mutant frequently exhibits enlarged, dumbbell-shaped chloroplasts, indicating a role for ARC5 in the constriction of the chloroplast division site. In a screen for chloroplast division mutants with a phenotype similar to arc5, two mutants, cpd25 and cpd45, were obtained. CPD45 was identified as being the same gene as FHY3, a key regulator of far-red light signaling recently shown to be involved in the regulation of ARC5. CPD25 was previously named FRS4 and is homologous to FHY3. We found that CPD25 is also required for the expression of ARC5, suggesting that its function is not redundant to that of FHY3. Moreover, cpd25 does not have the far-red light-sensing defect present in fhy3 and far1. Both FRS4/CPD25 and FHY3/CPD45 could bind to the FBS-like 'ACGCGC' motifs in the promoter region of ARC5, and the binding efficiency of FRS4/CPD25 was much higher than that of FHY3/CPD45. Unlike FHY3/CPD45, FRS4/CPD25 has no ARC5 activation activity. Our data suggest that FRS4/CPD25 and FHY3/CPD45 function as a heterodimer that cooperatively activates ARC5, that FRS4/CPD25 plays the major role in promoter binding, and that FHY3/CPD45 is largely responsible for the gene activation. This study not only provides insight into the mechanisms underlying the regulation of chloroplast division in higher plants, but also suggests a model that shows how members of a transcription factor family can evolve to have different DNA-binding and gene activation features.

  10. Optical Code-Division Multiple-Access and Wavelength Division Multiplexing: Hybrid Scheme Review

    Directory of Open Access Journals (Sweden)

    P. Susthitha Menon

    2012-01-01

    Full Text Available Problem statement: Hybrid Optical Code-Division Multiple-Access (OCDMA and Wavelength-Division Multiplexing (WDM have flourished as successful schemes for expanding the transmission capacity as well as enhancing the security for OCDMA. However, a comprehensive review related to this hybrid system are lacking currently. Approach: The purpose of this paper is to review the literature on OCDMA-WDM overlay systems, including our hybrid approach of one-dimensional coding of SAC OCDMA with WDM signals. In addition, we present an additional review of other categorios of hybrid WDM/OCDMA schemes, where codes of OCDMA can be employed on each WDM wavelength. Furthermore, an essential background of OCDMA, recent coding techniques and security issues are also presented. Results: Our results indicate that the feasibility of transmitting both OCDMA and WDM users on the same spectrum band can be achieved using MQC family code with an acceptable performance as well as good data confidentiality. In addition, the WDM interference signals can be suppressed properly for detection of optical broadband CDMA using notch filters. Conclusion: The paper provides a comprehensive overview of hybrid OCDMA-WDM systems and can be used as a baseline study for other scientists in the similar scope of research.

  11. Computed tomography assessment of temporomandibular joint position and dimensions in patients with class II division 1 and division 2 malocclusions

    Science.gov (United States)

    Ciger, Semra

    2017-01-01

    Background This study aimed to investigate and compare the positions and dimensions of the temporomandibular joint and its components, respectively, in patients with Class II division 1 and division 2 malocclusions. Material and Methods Computed tomography images of 14 patients with Class II division 1 and 14 patients with Class II division 2 malocclusion were included with a mean age of 11.4 ± 1.2 years. The following temporomandibular joint measurements were made with OsiriX medical imaging software program. From the sagittal images, the anterior, superior, and posterior joint spaces and the mandibular fossa depths were measured. From the axial images, the greatest anteroposterior and mediolateral diameters of the mandibular condyles, angles between the long axis of the mandibular condyle and midsagittal plane, and vertical distances from the geometric centers of the condyles to midsagittal plane were measured. The independent samples t-test was used for comparing the measurements between the two sides and between the Class II division 1 and 2 groups. Results No statistically significant differences were observed between the right and left temporomandibular joints; therefore, the data were pooled. There were statistically significant differences between the Class II division 1 and 2 groups with regard to mandibular fossa depth and anterior joint space measurements. Conclusions In Class II patients, the right and left temporomandibular joints were symmetrical. In the Class II division 1 group, the anterior joint space was wider than that in Class II division 2 group, and the mandibular fossa was deeper and wider in the Class II division 1 group. Key words:Temporomandibular joint, Class II malocclusion, Cone beam computed tomography. PMID:28298985

  12. Stability of networked control systems with multi-step delay based on time-division algorithm

    Institute of Scientific and Technical Information of China (English)

    Changlin MA; Huajing FANG

    2005-01-01

    A new control mode is proposed for a networked control system whose network-induced delay is longer than a sampling period. A time-division algorithm is presented to implement the control and for the mathematical modeling of such networked control system. The infinite horizon controller is designed, which renders the networked control system mean square exponentially stable. Simulation results show the validity of the proposed theory.

  13. Engineering Physics Division progress report for period ending November 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-01

    Separate abstracts are included for sections concerning measurement of nuclear cross sections and related quantities; nuclear cross-section evaluations and theory; nuclear cross-section processing, testing, and sensitivity analysis; engineering physics division integral experiments and their analyses; development of methods for shield and reactor analysis; analyses for specific systems or applications; energy model validation; systems reliability and operations research; and information analysis and distribution.

  14. Environmental Sciences Division. Annual progress report for period ending September 30, 1975

    Energy Technology Data Exchange (ETDEWEB)

    1976-08-01

    The energy crisis and creation of ERDA were dominant factors affecting the activities of the Environmental Sciences Division during the past year. Efforts primarily centered on coal conversion effluents, aquatic effects from power plants, terrestrial modeling of both radioactive and nonradioactive waste transport, mineral cycling, forest management, and information handling codes and techniques. A bibliography of publications, presentation, these, and other professional activities is included. (PCS)

  15. Gender role division in Japan and Korea : the relationship between realities and attitudes

    OpenAIRE

    2010-01-01

    This study examines the relation between the "attitudes" and the "realities" of gender role division and its influence on men's mental health in Japan and Korea. The data used in this study are the "Social Stratification and Social Mobility Survey" in Japan (SSM Japan 2005) and "the Social Stratification and Social Mobility Survey" in Korea (SSM Korea 2005). Based on general linear model, the following results were obtained: 1) Korean men experience more gaps between the attitudes and the ...

  16. Saying and doing gender: intergenerational transmission of attitudes towards the sexual division of labour

    OpenAIRE

    Platt, Lucinda; Polavieja, Javier

    2016-01-01

    The persistence of gender inequalities in the division of paid and unpaid work poses an important question for gender socialization research: what matters most for the intergenerational transmission of gender-role attitudes, parental own attitudes or parental behaviours? Recent explanations in cultural economics suggest that intentional attitudinal transmission is the main driver of cultural reproduction. In line with classical sex-role learning models, we contend, however, that what parents ...

  17. Maximum Entropy for the International Division of Labor

    National Research Council Canada - National Science Library

    Lei, Hongmei; Chen, Ying; Li, Ruiqi; He, Deli; Zhang, Jiang

    2015-01-01

    As a result of the international division of labor, the trade value distribution on different products substantiated by international trade flows can be regarded as one country's strategy for competition...

  18. Earth Sciences Division annual report 1981. [Lead abstract

    Energy Technology Data Exchange (ETDEWEB)

    1982-09-01

    Separate abstracts were prepared for the 59 papers of the 1981 annual report of the Earth Sciences Division at Lawrence Berkeley Laboratory. The general topics covered included nuclear waste isolation, geophysics and reservoir engineering, and geosciences. (KRM)

  19. Division for Heart Disease and Stroke Prevention: Data Trends & Maps

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CDC Division for Heart Disease and Stroke Prevention's Data Trends & Maps online tool allows searching for and view of health indicators related to Heart...

  20. Erie National Wildlife Refuge (Sugar Lake Division) [Land Status Map

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Erie National Wildlife Refuge. It was generated from rectified aerial photography,...