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Sample records for genetic constraints guide

  1. Constraints in Genetic Programming

    NASA Technical Reports Server (NTRS)

    Janikow, Cezary Z.

    1996-01-01

    Genetic programming refers to a class of genetic algorithms utilizing generic representation in the form of program trees. For a particular application, one needs to provide the set of functions, whose compositions determine the space of program structures being evolved, and the set of terminals, which determine the space of specific instances of those programs. The algorithm searches the space for the best program for a given problem, applying evolutionary mechanisms borrowed from nature. Genetic algorithms have shown great capabilities in approximately solving optimization problems which could not be approximated or solved with other methods. Genetic programming extends their capabilities to deal with a broader variety of problems. However, it also extends the size of the search space, which often becomes too large to be effectively searched even by evolutionary methods. Therefore, our objective is to utilize problem constraints, if such can be identified, to restrict this space. In this publication, we propose a generic constraint specification language, powerful enough for a broad class of problem constraints. This language has two elements -- one reduces only the number of program instances, the other reduces both the space of program structures as well as their instances. With this language, we define the minimal set of complete constraints, and a set of operators guaranteeing offspring validity from valid parents. We also show that these operators are not less efficient than the standard genetic programming operators if one preprocesses the constraints - the necessary mechanisms are identified.

  2. Genetic map construction with constraints

    SciTech Connect

    Clark, D.A.; Rawlings, C.J.; Soursenot, S.

    1994-12-31

    A pilot program, CME, is described for generating a physical genetic map from hybridization fingerprinting data. CME is implemented in the parallel constraint logic programming language ElipSys. The features of constraint logic programming are used to enable the integration of preexisting mapping information (partial probe orders from cytogenetic maps and local physical maps) into the global map generation process, while parallelism enables the search space to be traversed more efficiently. CME was tested using data from chromosome 2 of Schizosaccharomyces pombe and was found able to generate maps as well as (and sometimes better than) a more traditional method. This paper illustrates the practical benefits of using a symbolic logic programming language and shows that the features of constraint handling and parallel execution bring the development of practical systems based on Al programming technologies nearer to being a reality.

  3. Adaptive Divergence in Experimental Populations of Pseudomonas fluorescens. IV. Genetic Constraints Guide Evolutionary Trajectories in a Parallel Adaptive Radiation

    PubMed Central

    McDonald, Michael J.; Gehrig, Stefanie M.; Meintjes, Peter L.; Zhang, Xue-Xian; Rainey, Paul B.

    2009-01-01

    The capacity for phenotypic evolution is dependent upon complex webs of functional interactions that connect genotype and phenotype. Wrinkly spreader (WS) genotypes arise repeatedly during the course of a model Pseudomonas adaptive radiation. Previous work showed that the evolution of WS variation was explained in part by spontaneous mutations in wspF, a component of the Wsp-signaling module, but also drew attention to the existence of unknown mutational causes. Here, we identify two new mutational pathways (Aws and Mws) that allow realization of the WS phenotype: in common with the Wsp module these pathways contain a di-guanylate cyclase-encoding gene subject to negative regulation. Together, mutations in the Wsp, Aws, and Mws regulatory modules account for the spectrum of WS phenotype-generating mutations found among a collection of 26 spontaneously arising WS genotypes obtained from independent adaptive radiations. Despite a large number of potential mutational pathways, the repeated discovery of mutations in a small number of loci (parallel evolution) prompted the construction of an ancestral genotype devoid of known (Wsp, Aws, and Mws) regulatory modules to see whether the types derived from this genotype could converge upon the WS phenotype via a novel route. Such types—with equivalent fitness effects—did emerge, although they took significantly longer to do so. Together our data provide an explanation for why WS evolution follows a limited number of mutational pathways and show how genetic architecture can bias the molecular variation presented to selection. PMID:19704015

  4. Lagrangian and Hamiltonian constraints for guiding-center Hamiltonian theories

    SciTech Connect

    Tronko, Natalia; Brizard, Alain J.

    2015-11-15

    A consistent guiding-center Hamiltonian theory is derived by Lie-transform perturbation method, with terms up to second order in magnetic-field nonuniformity. Consistency is demonstrated by showing that the guiding-center transformation presented here satisfies separate Jacobian and Lagrangian constraints that have not been explored before. A new first-order term appearing in the guiding-center phase-space Lagrangian is identified through a calculation of the guiding-center polarization. It is shown that this new polarization term also yields a simpler expression of the guiding-center toroidal canonical momentum, which satisfies an exact conservation law in axisymmetric magnetic geometries. Finally, an application of the guiding-center Lagrangian constraint on the guiding-center Hamiltonian yields a natural interpretation for its higher-order corrections.

  5. Genetic constraints predict evolutionary divergence in Dalechampia blossoms

    PubMed Central

    Bolstad, Geir H.; Hansen, Thomas F.; Pélabon, Christophe; Falahati-Anbaran, Mohsen; Pérez-Barrales, Rocío; Armbruster, W. Scott

    2014-01-01

    If genetic constraints are important, then rates and direction of evolution should be related to trait evolvability. Here we use recently developed measures of evolvability to test the genetic constraint hypothesis with quantitative genetic data on floral morphology from the Neotropical vine Dalechampia scandens (Euphorbiaceae). These measures were compared against rates of evolution and patterns of divergence among 24 populations in two species in the D. scandens species complex. We found clear evidence for genetic constraints, particularly among traits that were tightly phenotypically integrated. This relationship between evolvability and evolutionary divergence is puzzling, because the estimated evolvabilities seem too large to constitute real constraints. We suggest that this paradox can be explained by a combination of weak stabilizing selection around moving adaptive optima and small realized evolvabilities relative to the observed additive genetic variance. PMID:25002700

  6. Genetic constraints predict evolutionary divergence in Dalechampia blossoms.

    PubMed

    Bolstad, Geir H; Hansen, Thomas F; Pélabon, Christophe; Falahati-Anbaran, Mohsen; Pérez-Barrales, Rocío; Armbruster, W Scott

    2014-08-19

    If genetic constraints are important, then rates and direction of evolution should be related to trait evolvability. Here we use recently developed measures of evolvability to test the genetic constraint hypothesis with quantitative genetic data on floral morphology from the Neotropical vine Dalechampia scandens (Euphorbiaceae). These measures were compared against rates of evolution and patterns of divergence among 24 populations in two species in the D. scandens species complex. We found clear evidence for genetic constraints, particularly among traits that were tightly phenotypically integrated. This relationship between evolvability and evolutionary divergence is puzzling, because the estimated evolvabilities seem too large to constitute real constraints. We suggest that this paradox can be explained by a combination of weak stabilizing selection around moving adaptive optima and small realized evolvabilities relative to the observed additive genetic variance. PMID:25002700

  7. Active constraint control for image-guided robotic surgery.

    PubMed

    Yen, P-L; Davies, B L

    2010-01-01

    The concept of active constraint control for image-guided robotic surgery is introduced, together with its benefits and a short outline of its history. The clinical use of active constraint control in orthopaedic surgery is discussed, together with the outcomes of a clinical trial for unicondylar knee replacement surgery. The evolution of the robotic design from large costly structures towards simpler, more cost-effective systems is also presented, leading to the design of the Acrobot 'Sculptor' system. A new approach to the achievement of robotic total knee replacement is also presented, in which a high-speed rotary cutter is used to slice through the bone to achieve a speedy resection. The control concept is presented, together with the results of trials on animal bones and a cadaver, showing that it is possible to remove large quantities of bone both quickly and accurately.

  8. Making Sense of Your Genes: A Guide to Genetic Counseling

    MedlinePlus

    Making Sense of Your Genes a Guide to Genetic Counseling 1 A Guide to Genetic Counseling Contents What is genetic counseling? 1 Why might I ... methods contained in the material therein. Understanding Your Genes What is genetic counseling? The goal of genetic ...

  9. Genetic constraints on dishonesty and caste dimorphism in an ant.

    PubMed

    Holman, Luke; Linksvayer, Timothy A; d'Ettorre, Patrizia

    2013-02-01

    The ultimate causes of honest signaling remain a subject of debate, with questions remaining over the relative importance of costs and constraints. Signal costs may make dishonesty prohibitively expensive, while genetic constraints could make it impossible. We investigated honest signaling using full-sib analysis and parent-offspring regression in the ant Lasius niger, in which queens produce a cuticular hydrocarbon-based pheromone that signals fertility and inhibits worker reproduction and aggression. We found multiple lines of evidence that cuticular hydrocarbon production is genetically correlated with oogenesis and that the queen pheromone 3-methylhentriacontane and other 3-methylalkanes have strong genetic links with fertility relative to other cuticular hydrocarbons. These genetic correlations may maintain honesty in the face of directional selection on signaling and explain the putatively widespread use of cuticular hydrocarbons in fertility signaling across the social insects. We also found evidence for a positive genetic correlation for fertility between the castes; that is, the most fertile queens produced especially fertile workers. These results highlight that intercaste genetic correlations could constrain the evolution of queen-worker dimorphism, such that worker reproduction may sometimes reflect a nonadaptive "caste load" rather than positively selected cheating. PMID:23348771

  10. Constraints on the Genetic and Antigenic Variability of Measles Virus

    PubMed Central

    Beaty, Shannon M.; Lee, Benhur

    2016-01-01

    Antigenic drift and genetic variation are significantly constrained in measles virus (MeV). Genetic stability of MeV is exceptionally high, both in the lab and in the field, and few regions of the genome allow for rapid genetic change. The regions of the genome that are more tolerant of mutations (i.e., the untranslated regions and certain domains within the N, C, V, P, and M proteins) indicate genetic plasticity or structural flexibility in the encoded proteins. Our analysis reveals that strong constraints in the envelope proteins (F and H) allow for a single serotype despite known antigenic differences among its 24 genotypes. This review describes some of the many variables that limit the evolutionary rate of MeV. The high genomic stability of MeV appears to be a shared property of the Paramyxovirinae, suggesting a common mechanism that biologically restricts the rate of mutation. PMID:27110809

  11. Constraints on the Genetic and Antigenic Variability of Measles Virus.

    PubMed

    Beaty, Shannon M; Lee, Benhur

    2016-04-01

    Antigenic drift and genetic variation are significantly constrained in measles virus (MeV). Genetic stability of MeV is exceptionally high, both in the lab and in the field, and few regions of the genome allow for rapid genetic change. The regions of the genome that are more tolerant of mutations (i.e., the untranslated regions and certain domains within the N, C, V, P, and M proteins) indicate genetic plasticity or structural flexibility in the encoded proteins. Our analysis reveals that strong constraints in the envelope proteins (F and H) allow for a single serotype despite known antigenic differences among its 24 genotypes. This review describes some of the many variables that limit the evolutionary rate of MeV. The high genomic stability of MeV appears to be a shared property of the Paramyxovirinae, suggesting a common mechanism that biologically restricts the rate of mutation. PMID:27110809

  12. Bypass of genetic constraints during mutator evolution to antibiotic resistance

    PubMed Central

    Couce, Alejandro; Rodríguez-Rojas, Alexandro; Blázquez, Jesús

    2015-01-01

    Genetic constraints can block many mutational pathways to optimal genotypes in real fitness landscapes, yet the extent to which this can limit evolution remains to be determined. Interestingly, mutator bacteria elevate only specific types of mutations, and therefore could be very sensitive to genetic constraints. Testing this possibility is not only clinically relevant, but can also inform about the general impact of genetic constraints in adaptation. Here, we evolved 576 populations of two mutator and one wild-type Escherichia coli to doubling concentrations of the antibiotic cefotaxime. All strains carried TEM-1, a β-lactamase enzyme well known by its low availability of mutational pathways. Crucially, one of the mutators does not elevate any of the relevant first-step mutations known to improve cefatoximase activity. Despite this, both mutators displayed a similar ability to evolve more than 1000-fold resistance. Initial adaptation proceeded in parallel through general multi-drug resistance mechanisms. High-level resistance, in contrast, was achieved through divergent paths; with the a priori inferior mutator exploiting alternative mutational pathways in PBP3, the target of the antibiotic. These results have implications for mutator management in clinical infections and, more generally, illustrate that limits to natural selection in real organisms are alleviated by the existence of multiple loci contributing to fitness. PMID:25716795

  13. Bypass of genetic constraints during mutator evolution to antibiotic resistance.

    PubMed

    Couce, Alejandro; Rodríguez-Rojas, Alexandro; Blázquez, Jesús

    2015-04-01

    Genetic constraints can block many mutational pathways to optimal genotypes in real fitness landscapes, yet the extent to which this can limit evolution remains to be determined. Interestingly, mutator bacteria elevate only specific types of mutations, and therefore could be very sensitive to genetic constraints. Testing this possibility is not only clinically relevant, but can also inform about the general impact of genetic constraints in adaptation. Here, we evolved 576 populations of two mutator and one wild-type Escherichia coli to doubling concentrations of the antibiotic cefotaxime. All strains carried TEM-1, a β-lactamase enzyme well known by its low availability of mutational pathways. Crucially, one of the mutators does not elevate any of the relevant first-step mutations known to improve cefatoximase activity. Despite this, both mutators displayed a similar ability to evolve more than 1000-fold resistance. Initial adaptation proceeded in parallel through general multi-drug resistance mechanisms. High-level resistance, in contrast, was achieved through divergent paths; with the a priori inferior mutator exploiting alternative mutational pathways in PBP3, the target of the antibiotic. These results have implications for mutator management in clinical infections and, more generally, illustrate that limits to natural selection in real organisms are alleviated by the existence of multiple loci contributing to fitness.

  14. Using activity-based costing and theory of constraints to guide continuous improvement in managed care.

    PubMed

    Roybal, H; Baxendale, S J; Gupta, M

    1999-01-01

    Activity-based costing and the theory of constraints have been applied successfully in many manufacturing organizations. Recently, those concepts have been applied in service organizations. This article describes the application of activity-based costing and the theory of constraints in a managed care mental health and substance abuse organization. One of the unique aspects of this particular application was the integration of activity-based costing and the theory of constraints to guide process improvement efforts. This article describes the activity-based costing model and the application of the theory of constraint's focusing steps with an emphasis on unused capacities of activities in the organization.

  15. Using activity-based costing and theory of constraints to guide continuous improvement in managed care.

    PubMed

    Roybal, H; Baxendale, S J; Gupta, M

    1999-01-01

    Activity-based costing and the theory of constraints have been applied successfully in many manufacturing organizations. Recently, those concepts have been applied in service organizations. This article describes the application of activity-based costing and the theory of constraints in a managed care mental health and substance abuse organization. One of the unique aspects of this particular application was the integration of activity-based costing and the theory of constraints to guide process improvement efforts. This article describes the activity-based costing model and the application of the theory of constraint's focusing steps with an emphasis on unused capacities of activities in the organization. PMID:10350791

  16. Genetic constraints on adaptive evolution in principle and in practice

    NASA Astrophysics Data System (ADS)

    Weinreich, Daniel

    2014-03-01

    Geneticists have long recognized that pairs of mutations often produce surprising effects on the organism, given their effects in isolation. Such mutational interactions are called epistasis. Importantly, epistasis among mutations influencing an organism's survival or reproductive success can constrain the temporal order in which mutations will be favored by natural selection. After exploring these theoretical considerations more fully, we will demonstrate substantial epistatic constraint on the evolution of an enzyme that confers bacterial antibiotic resistance. Such epistatically induced constraints turn out to be rather common in enzyme evolution, and we will briefly discuss recent work that seeks to explicate its mechanistic basis using methods of molecular and structural biology. Finally we observe that the epistatic interaction between two mutations itself often varies with genetic context, implying the existence of higher-order interactions. We present a computational framework for assessing magnitude of epistatic interactions of all orders, and show that non-negligible epistatic interactions of all orders are common in a diverse set of biological systems. Work supported by NIGMS Award R01GM095728 and NSF Emerging Frontiers Award 1038657

  17. Language Evolution: Constraints and Opportunities From Modern Genetics.

    PubMed

    Dediu, Dan; Christiansen, Morten H

    2016-04-01

    Our understanding of language, its origins and subsequent evolution (including language change), is shaped not only by data and theories from the language sciences, but also fundamentally by the biological sciences. Recent developments in genetics and evolutionary theory offer both very strong constraints on what scenarios of language evolution are possible and probable, but also offer exciting opportunities for understanding otherwise puzzling phenomena. Due to the intrinsic breathtaking rate of advancement in these fields, and the complexity, subtlety, and sometimes apparent non-intuitiveness of the phenomena discovered, some of these recent developments have either being completely missed by language scientists or misperceived and misrepresented. In this short paper, we offer an update on some of these findings and theoretical developments through a selection of illustrative examples and discussions that cast new light on current debates in the language sciences. The main message of our paper is that life is much more complex and nuanced than anybody could have predicted even a few decades ago, and that we need to be flexible in our theorizing instead of embracing a priori dogmas and trying to patch paradigms that are no longer satisfactory.

  18. Genetics and behavior: a guide for practitioners.

    PubMed

    Overall, Karen L; Tiira, Katriina; Broach, Desiree; Bryant, Deborah

    2014-05-01

    Phenotyping behavior is difficult, partly because behavior is almost always influenced by environment. Using objective terms/criteria to evaluate behaviors is best; the more objective the assessment, the more likely underlying genetic patterns will be identified. Behavioral pathologies, and highly desirable behavioral characteristics/traits, are likely complex, meaning that multiple genes are probably involved, and therefore simple genetic tests are less possible. Breeds can be improved using traditional quantitative genetic methods; unfortunately, this also creates the possibility of inadvertently selecting for covarying undesirable behaviors. Patterns of behaviors within families and breed lines are still the best guidelines for genetic counseling in dogs. PMID:24766696

  19. Genetics and behavior: a guide for practitioners.

    PubMed

    Overall, Karen L; Tiira, Katriina; Broach, Desiree; Bryant, Deborah

    2014-05-01

    Phenotyping behavior is difficult, partly because behavior is almost always influenced by environment. Using objective terms/criteria to evaluate behaviors is best; the more objective the assessment, the more likely underlying genetic patterns will be identified. Behavioral pathologies, and highly desirable behavioral characteristics/traits, are likely complex, meaning that multiple genes are probably involved, and therefore simple genetic tests are less possible. Breeds can be improved using traditional quantitative genetic methods; unfortunately, this also creates the possibility of inadvertently selecting for covarying undesirable behaviors. Patterns of behaviors within families and breed lines are still the best guidelines for genetic counseling in dogs.

  20. The hitchhiker's guide to Xenopus genetics.

    PubMed

    Abu-Daya, Anita; Khokha, Mustafa K; Zimmerman, Lyle B

    2012-03-01

    A decade after the human genome sequence, most vertebrate gene functions remain poorly understood, limiting benefits to human health from rapidly advancing genomic technologies. Systematic in vivo functional analysis is ideally suited to the experimentally accessible Xenopus embryo, which combines embryological accessibility with a broad range of transgenic, biochemical, and gain-of-function assays. The diploid X. tropicalis adds loss-of-function genetics and enhanced genomics to this repertoire. In the last decade, diverse phenotypes have been recovered from genetic screens, mutations have been cloned, and reverse genetics in the form of TILLING and targeted gene editing have been established. Simple haploid genetics and gynogenesis and the very large number of embryos produced streamline screening and mapping. Improved genomic resources and the revolution in high-throughput sequencing are transforming mutation cloning and reverse genetic approaches. The combination of loss-of-function mutant backgrounds with the diverse array of conventional Xenopus assays offers a uniquely flexible platform for analysis of gene function in vertebrate development. PMID:22344745

  1. A guided search genetic algorithm using mined rules for optimal affective product design

    NASA Astrophysics Data System (ADS)

    Fung, Chris K. Y.; Kwong, C. K.; Chan, Kit Yan; Jiang, H.

    2014-08-01

    Affective design is an important aspect of new product development, especially for consumer products, to achieve a competitive edge in the marketplace. It can help companies to develop new products that can better satisfy the emotional needs of customers. However, product designers usually encounter difficulties in determining the optimal settings of the design attributes for affective design. In this article, a novel guided search genetic algorithm (GA) approach is proposed to determine the optimal design attribute settings for affective design. The optimization model formulated based on the proposed approach applied constraints and guided search operators, which were formulated based on mined rules, to guide the GA search and to achieve desirable solutions. A case study on the affective design of mobile phones was conducted to illustrate the proposed approach and validate its effectiveness. Validation tests were conducted, and the results show that the guided search GA approach outperforms the GA approach without the guided search strategy in terms of GA convergence and computational time. In addition, the guided search optimization model is capable of improving GA to generate good solutions for affective design.

  2. Guiding rational reservoir flood operation using penalty-type genetic algorithm

    NASA Astrophysics Data System (ADS)

    Chang, Li-Chiu

    2008-06-01

    SummaryReal-time flood control of a multi-purpose reservoir should consider decreasing the flood peak stage downstream and storing floodwaters for future usage during typhoon seasons. This study proposes a reservoir flood control optimization model with linguistic description of requirements and existing regulations for rational operating decisions. The approach involves formulating reservoir flood operation as an optimization problem and using the genetic algorithm (GA) as a search engine. The optimizing formulation is expressed not only by mathematical forms of objective function and constraints, but also by no analytic expression in terms of parameters. GA is used to search a global optimum of a mixture of mathematical and nonmathematical formulations. Due to the great number of constraints and flood control requirements, it is difficult to reach a solution without violating constraints. To tackle this bottleneck, the proper penalty strategy for each parameter is proposed to guide the GA searching process. The proposed approach is applied to the Shihmen reservoir in North Taiwan for finding the rational release and desired storage as a case study. The hourly historical data sets of 29 typhoon events that have hit the area in last thirty years are investigated bye the proposed method. To demonstrate the effectiveness of the proposed approach, the simplex method was performed. The results demonstrated that a penalty-type genetic algorithm could effectively provide rational hydrographs to reduce flood damage during the flood operation and to increase final storage for future usages.

  3. A Method of Solving Scheduling Problems Using Improved Guided Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Ou, Gyouhi; Tamura, Hiroki; Tanno, Koichi; Tang, Zheng

    In this paper, an improved guided genetic algorithm is proposed forJob-shop schueduling problem. The proposed method is improved by genetic algorithm using multipliers which can be adjusted during the search process. The simulation results based on some benchmark problems that proves the proposed method can find better solutions than genetic algorithm and original guided genetic algorithm.

  4. Genetic constraints for thermal coadaptation in Drosophila subobscura

    PubMed Central

    2010-01-01

    Background Behaviour has been traditionally viewed as a driver of subsequent evolution because behavioural adjustments expose organisms to novel environments, which may result in a correlated evolution on other traits. In Drosophila subobscura, thermal preference and heat tolerance are linked to chromosomal inversion polymorphisms that show parallel latitudinal clines worldwide, such that "cold-climate" ("warm-climate") chromosome arrangements collectively favour a coherent response to colder (warmer) settings as flies carrying them prefer colder (warmer) conditions and have lower (higher) knock out temperatures. Yet, it is not clear whether a genetic correlation between thermal preference and heat tolerance can partially underlie such response. Results We have analyzed the genetic basis of thermal preference and heat tolerance using isochromosomal lines in D. subobscura. Chromosome arrangements on the O chromosome were known to have a biometrical effect on thermal preference in a laboratory temperature gradient, and also harbour several genes involved in the heat shock response; in particular, the genes Hsp68 and Hsp70. Our results corroborate that arrangements on chromosome O affect adult thermal preference in a laboratory temperature gradient, with cold-climate Ost carriers displaying a lower thermal preference than their warm-climate O3+4 and O3+4+8 counterparts. However, these chromosome arrangements did not have any effect on adult heat tolerance and, hence, we putatively discard a genetic covariance between both traits arising from linkage disequilibrium between genes affecting thermal preference and candidate genes for heat shock resistance. Nonetheless, a possible association of juvenile thermal preference and heat resistance warrants further analysis. Conclusions Thermal preference and heat tolerance in the isochromosomal lines of D. subobscura appear to be genetically independent, which might potentially prevent a coherent response of behaviour and

  5. Deformable Image Registration with Local Rigidity Constraints for Cone-Beam CT Guided Spine Surgery

    PubMed Central

    Reaungamornrat, S.; Wang, A. S.; Uneri, A.; Otake, Y.; Khanna, A. J.; Siewerdsen, J. H.

    2014-01-01

    Image-guided spine surgery is associated with reduced co-morbidity and improved surgical outcome. However, precise localization of target anatomy and adjacent nerves and vessels relative to planning information (e.g., device trajectories) can be challenged by anatomical deformation. Rigid registration alone fails to account for deformation associated with changes in spine curvature, and conventional deformable registration fails to account for rigidity of the vertebrae, causing unrealistic distortions in the registered image that can confound high-precision surgery. We developed and evaluated a deformable registration method capable of preserving rigidity of bones while resolving the deformation of surrounding soft tissue. The method aligns preoperative CT to intraoperative CBCT using free-form deformation (FFD) with constraints on rigid body motion imposed according to a simple intensity threshold of bone intensities. The constraints enforced 3 properties of a rigid transformation – namely, constraints on affinity (AC), orthogonality (OC), and properness (PC). The method also incorporated an injectivity constraint (IC) to preserve topology. Physical experiments involving phantoms, an ovine spine, and a human cadaver as well as digital simulations were performed to evaluate the sensitivity to registration parameters, preservation of rigid body morphology, and overall registration accuracy of constrained FFD in comparison to conventional unconstrained FFD (denoted uFFD) and Demons registration. FFD with orthogonality and injectivity constraints (denoted FFD+OC+IC) demonstrated improved performance compared to uFFD and Demons. Affinity and properness constraints offered little or no additional improvement. The FFD+OC+IC method preserved rigid body morphology at near-ideal values of zero dilatation (𝒟 = 0.05, compared to 0.39 and 0.56 for uFFD and Demons, respectively) and shear (𝒮 = 0.08, compared to 0.36 and 0.44 for uFFD and Demons, respectively

  6. Genetic algorithm-based regularization parameter estimation for the inverse electrocardiography problem using multiple constraints.

    PubMed

    Dogrusoz, Yesim Serinagaoglu; Gavgani, Alireza Mazloumi

    2013-04-01

    In inverse electrocardiography, the goal is to estimate cardiac electrical sources from potential measurements on the body surface. It is by nature an ill-posed problem, and regularization must be employed to obtain reliable solutions. This paper employs the multiple constraint solution approach proposed in Brooks et al. (IEEE Trans Biomed Eng 46(1):3-18, 1999) and extends its practical applicability to include more than two constraints by finding appropriate values for the multiple regularization parameters. Here, we propose the use of real-valued genetic algorithms for the estimation of multiple regularization parameters. Theoretically, it is possible to include as many constraints as necessary and find the corresponding regularization parameters using this approach. We have shown the feasibility of our method using two and three constraints. The results indicate that GA could be a good approach for the estimation of multiple regularization parameters.

  7. Deformable image registration with local rigidity constraints for cone-beam CT-guided spine surgery.

    PubMed

    Reaungamornrat, S; Wang, A S; Uneri, A; Otake, Y; Khanna, A J; Siewerdsen, J H

    2014-07-21

    Image-guided spine surgery (IGSS) is associated with reduced co-morbidity and improved surgical outcome. However, precise localization of target anatomy and adjacent nerves and vessels relative to planning information (e.g., device trajectories) can be challenged by anatomical deformation. Rigid registration alone fails to account for deformation associated with changes in spine curvature, and conventional deformable registration fails to account for rigidity of the vertebrae, causing unrealistic distortions in the registered image that can confound high-precision surgery. We developed and evaluated a deformable registration method capable of preserving rigidity of bones while resolving the deformation of surrounding soft tissue. The method aligns preoperative CT to intraoperative cone-beam CT (CBCT) using free-form deformation (FFD) with constraints on rigid body motion imposed according to a simple intensity threshold of bone intensities. The constraints enforced three properties of a rigid transformation-namely, constraints on affinity (AC), orthogonality (OC), and properness (PC). The method also incorporated an injectivity constraint (IC) to preserve topology. Physical experiments involving phantoms, an ovine spine, and a human cadaver as well as digital simulations were performed to evaluate the sensitivity to registration parameters, preservation of rigid body morphology, and overall registration accuracy of constrained FFD in comparison to conventional unconstrained FFD (uFFD) and Demons registration. FFD with orthogonality and injectivity constraints (denoted FFD+OC+IC) demonstrated improved performance compared to uFFD and Demons. Affinity and properness constraints offered little or no additional improvement. The FFD+OC+IC method preserved rigid body morphology at near-ideal values of zero dilatation (D = 0.05, compared to 0.39 and 0.56 for uFFD and Demons, respectively) and shear (S = 0.08, compared to 0.36 and 0.44 for uFFD and Demons, respectively

  8. Deformable image registration with local rigidity constraints for cone-beam CT-guided spine surgery

    NASA Astrophysics Data System (ADS)

    Reaungamornrat, S.; Wang, A. S.; Uneri, A.; Otake, Y.; Khanna, A. J.; Siewerdsen, J. H.

    2014-07-01

    Image-guided spine surgery (IGSS) is associated with reduced co-morbidity and improved surgical outcome. However, precise localization of target anatomy and adjacent nerves and vessels relative to planning information (e.g., device trajectories) can be challenged by anatomical deformation. Rigid registration alone fails to account for deformation associated with changes in spine curvature, and conventional deformable registration fails to account for rigidity of the vertebrae, causing unrealistic distortions in the registered image that can confound high-precision surgery. We developed and evaluated a deformable registration method capable of preserving rigidity of bones while resolving the deformation of surrounding soft tissue. The method aligns preoperative CT to intraoperative cone-beam CT (CBCT) using free-form deformation (FFD) with constraints on rigid body motion imposed according to a simple intensity threshold of bone intensities. The constraints enforced three properties of a rigid transformation—namely, constraints on affinity (AC), orthogonality (OC), and properness (PC). The method also incorporated an injectivity constraint (IC) to preserve topology. Physical experiments involving phantoms, an ovine spine, and a human cadaver as well as digital simulations were performed to evaluate the sensitivity to registration parameters, preservation of rigid body morphology, and overall registration accuracy of constrained FFD in comparison to conventional unconstrained FFD (uFFD) and Demons registration. FFD with orthogonality and injectivity constraints (denoted FFD+OC+IC) demonstrated improved performance compared to uFFD and Demons. Affinity and properness constraints offered little or no additional improvement. The FFD+OC+IC method preserved rigid body morphology at near-ideal values of zero dilatation ({ D} = 0.05, compared to 0.39 and 0.56 for uFFD and Demons, respectively) and shear ({ S} = 0.08, compared to 0.36 and 0.44 for uFFD and Demons

  9. Deformable image registration with local rigidity constraints for cone-beam CT-guided spine surgery.

    PubMed

    Reaungamornrat, S; Wang, A S; Uneri, A; Otake, Y; Khanna, A J; Siewerdsen, J H

    2014-07-21

    Image-guided spine surgery (IGSS) is associated with reduced co-morbidity and improved surgical outcome. However, precise localization of target anatomy and adjacent nerves and vessels relative to planning information (e.g., device trajectories) can be challenged by anatomical deformation. Rigid registration alone fails to account for deformation associated with changes in spine curvature, and conventional deformable registration fails to account for rigidity of the vertebrae, causing unrealistic distortions in the registered image that can confound high-precision surgery. We developed and evaluated a deformable registration method capable of preserving rigidity of bones while resolving the deformation of surrounding soft tissue. The method aligns preoperative CT to intraoperative cone-beam CT (CBCT) using free-form deformation (FFD) with constraints on rigid body motion imposed according to a simple intensity threshold of bone intensities. The constraints enforced three properties of a rigid transformation-namely, constraints on affinity (AC), orthogonality (OC), and properness (PC). The method also incorporated an injectivity constraint (IC) to preserve topology. Physical experiments involving phantoms, an ovine spine, and a human cadaver as well as digital simulations were performed to evaluate the sensitivity to registration parameters, preservation of rigid body morphology, and overall registration accuracy of constrained FFD in comparison to conventional unconstrained FFD (uFFD) and Demons registration. FFD with orthogonality and injectivity constraints (denoted FFD+OC+IC) demonstrated improved performance compared to uFFD and Demons. Affinity and properness constraints offered little or no additional improvement. The FFD+OC+IC method preserved rigid body morphology at near-ideal values of zero dilatation (D = 0.05, compared to 0.39 and 0.56 for uFFD and Demons, respectively) and shear (S = 0.08, compared to 0.36 and 0.44 for uFFD and Demons, respectively

  10. Constraints on decision making: implications from genetics, personality, and addiction.

    PubMed

    Baker, Travis E; Stockwell, Tim; Holroyd, Clay B

    2013-09-01

    An influential neurocomputational theory of the biological mechanisms of decision making, the "basal ganglia go/no-go model," holds that individual variability in decision making is determined by differences in the makeup of a striatal system for approach and avoidance learning. The model has been tested empirically with the probabilistic selection task (PST), which determines whether individuals learn better from positive or negative feedback. In accordance with the model, in the present study we examined whether an individual's ability to learn from positive and negative reinforcement can be predicted by genetic factors related to the midbrain dopamine system. We also asked whether psychiatric and personality factors related to substance dependence and dopamine affect PST performance. Although we found characteristics that predicted individual differences in approach versus avoidance learning, these observations were qualified by additional findings that appear inconsistent with the predictions of the go/no-go model. These results highlight a need for future research to validate the PST as a measure of basal ganglia reward learning. PMID:23658007

  11. Constraints on decision making: implications from genetics, personality, and addiction.

    PubMed

    Baker, Travis E; Stockwell, Tim; Holroyd, Clay B

    2013-09-01

    An influential neurocomputational theory of the biological mechanisms of decision making, the "basal ganglia go/no-go model," holds that individual variability in decision making is determined by differences in the makeup of a striatal system for approach and avoidance learning. The model has been tested empirically with the probabilistic selection task (PST), which determines whether individuals learn better from positive or negative feedback. In accordance with the model, in the present study we examined whether an individual's ability to learn from positive and negative reinforcement can be predicted by genetic factors related to the midbrain dopamine system. We also asked whether psychiatric and personality factors related to substance dependence and dopamine affect PST performance. Although we found characteristics that predicted individual differences in approach versus avoidance learning, these observations were qualified by additional findings that appear inconsistent with the predictions of the go/no-go model. These results highlight a need for future research to validate the PST as a measure of basal ganglia reward learning.

  12. Genetic code evolution reveals the neutral emergence of mutational robustness, and information as an evolutionary constraint.

    PubMed

    Massey, Steven E

    2015-01-01

    The standard genetic code (SGC) is central to molecular biology and its origin and evolution is a fundamental problem in evolutionary biology, the elucidation of which promises to reveal much about the origins of life. In addition, we propose that study of its origin can also reveal some fundamental and generalizable insights into mechanisms of molecular evolution, utilizing concepts from complexity theory. The first is that beneficial traits may arise by non-adaptive processes, via a process of "neutral emergence". The structure of the SGC is optimized for the property of error minimization, which reduces the deleterious impact of point mutations. Via simulation, it can be shown that genetic codes with error minimization superior to the SGC can emerge in a neutral fashion simply by a process of genetic code expansion via tRNA and aminoacyl-tRNA synthetase duplication, whereby similar amino acids are added to codons related to that of the parent amino acid. This process of neutral emergence has implications beyond that of the genetic code, as it suggests that not all beneficial traits have arisen by the direct action of natural selection; we term these "pseudaptations", and discuss a range of potential examples. Secondly, consideration of genetic code deviations (codon reassignments) reveals that these are mostly associated with a reduction in proteome size. This code malleability implies the existence of a proteomic constraint on the genetic code, proportional to the size of the proteome (P), and that its reduction in size leads to an "unfreezing" of the codon - amino acid mapping that defines the genetic code, consistent with Crick's Frozen Accident theory. The concept of a proteomic constraint may be extended to propose a general informational constraint on genetic fidelity, which may be used to explain variously, differences in mutation rates in genomes with differing proteome sizes, differences in DNA repair capacity and genome GC content between organisms, a

  13. Genetic Code Evolution Reveals the Neutral Emergence of Mutational Robustness, and Information as an Evolutionary Constraint

    PubMed Central

    Massey, Steven E.

    2015-01-01

    The standard genetic code (SGC) is central to molecular biology and its origin and evolution is a fundamental problem in evolutionary biology, the elucidation of which promises to reveal much about the origins of life. In addition, we propose that study of its origin can also reveal some fundamental and generalizable insights into mechanisms of molecular evolution, utilizing concepts from complexity theory. The first is that beneficial traits may arise by non-adaptive processes, via a process of “neutral emergence”. The structure of the SGC is optimized for the property of error minimization, which reduces the deleterious impact of point mutations. Via simulation, it can be shown that genetic codes with error minimization superior to the SGC can emerge in a neutral fashion simply by a process of genetic code expansion via tRNA and aminoacyl-tRNA synthetase duplication, whereby similar amino acids are added to codons related to that of the parent amino acid. This process of neutral emergence has implications beyond that of the genetic code, as it suggests that not all beneficial traits have arisen by the direct action of natural selection; we term these “pseudaptations”, and discuss a range of potential examples. Secondly, consideration of genetic code deviations (codon reassignments) reveals that these are mostly associated with a reduction in proteome size. This code malleability implies the existence of a proteomic constraint on the genetic code, proportional to the size of the proteome (P), and that its reduction in size leads to an “unfreezing” of the codon – amino acid mapping that defines the genetic code, consistent with Crick’s Frozen Accident theory. The concept of a proteomic constraint may be extended to propose a general informational constraint on genetic fidelity, which may be used to explain variously, differences in mutation rates in genomes with differing proteome sizes, differences in DNA repair capacity and genome GC content

  14. Trait associations across evolutionary time within a drosophila phylogeny: correlated selection or genetic constraint?

    PubMed

    Kellermann, Vanessa; Overgaard, Johannes; Loeschcke, Volker; Kristensen, Torsten Nygaard; Hoffmann, Ary A

    2013-01-01

    Traits do not evolve independently. To understand how trait changes under selection might constrain adaptive changes, phenotypic and genetic correlations are typically considered within species, but these capture constraints across a few generations rather than evolutionary time. For longer-term constraints, comparisons are needed across species but associations may arise because of correlated selection pressures rather than genetic interactions. Implementing a unique approach, we use known patterns of selection to separate likely trait correlations arising due to correlated selection from those reflecting genetic constraints. We examined the evolution of stress resistance in >90 Drosophila species adapted to a range of environments, while controlling for phylogeny. Initially we examined the role of climate and phylogeny in shaping the evolution of starvation and body size, two traits previously not examined in this context. Following correction for phylogeny only a weak relationship between climate and starvation resistance was detected, while all of the variation in the relationship between body size and climate could be attributed to phylogeny. Species were divided into three environmental groups (hot and dry, hot and wet, cold) with the expectation that, if genetic correlations underpin trait correlations, these would persist irrespective of the environment, whereas selection-driven evolution should produce correlations dependent on the environment. We found positive associations between most traits in hot and dry environments coupled with high trait means. In contrast few trait correlations were observed in hot/wet and cold environments. These results suggest trait associations are primarily driven by correlated selection rather than genetic interactions, highlighting that such interactions are unlikely to limit evolution of stress resistance.

  15. Pharmacogenetics: Using Genetic Information to Guide Drug Therapy

    PubMed Central

    CHANG, KU-LANG; WEITZEL, KRISTIN; SCHMIDT, SIEGFRIED

    2016-01-01

    Clinical pharmacogenetics, the use of genetic data to guide drug therapy decisions, is beginning to be used for medications commonly prescribed by family physicians. However, clinicians are largely unfamiliar with principles supporting clinical use of this type of data. For example, genetic variability in the cytochrome P450 2D6 drug metabolizing enzyme can alter the clinical effects of some opioid analgesics (e.g., codeine, tramadol), whereas variability in the CYP2C19 enzyme affects the antiplatelet agent clopidogrel. If testing is performed, patients who are ultrarapid or poor metabolizers of CYP2D6 should avoid codeine use (and possibly tramadol, hydrocodone, and oxycodone) because of the potential for increased toxicity or lack of effectiveness. Patients undergoing percutaneous coronary intervention for acute coronary syndromes who are known to be poor metabolizers of CYP2C19 should consider alternate antiplatelet therapy (e.g., ticagrelor, prasugrel). Some guidelines are available that address appropriate drug therapy changes, and others are in development. Additionally, a number of clinical resources are emerging to support family physicians in the use of pharmacogenetics. When used appropriately, pharmacogenetic testing can be a practical tool to optimize drug therapy and avoid medication adverse effects. PMID:26447442

  16. Pharmacogenetics: Using Genetic Information to Guide Drug Therapy.

    PubMed

    Chang, Ku-Lang; Weitzel, Kristin; Schmidt, Siegfried

    2015-10-01

    Clinical pharmacogenetics, the use of genetic data to guide drug therapy decisions, is beginning to be used for medications commonly prescribed by family physicians. However, clinicians are largely unfamiliar with principles supporting clinical use of this type of data. For example, genetic variability in the cytochrome P450 2D6 drug metabolizing enzyme can alter the clinical effects of some opioid analgesics (e.g., codeine, tramadol), whereas variability in the CYP2C19 enzyme affects the antiplatelet agent clopidogrel. If testing is performed, patients who are ultrarapid or poor metabolizers of CYP2D6 should avoid codeine use (and possibly tramadol, hydrocodone, and oxycodone) because of the potential for increased toxicity or lack of effectiveness. Patients undergoing percutaneous coronary intervention for acute coronary syndromes who are known to be poor metabolizers of CYP2C19 should consider alternate antiplatelet therapy (e.g., ticagrelor, prasugrel). Some guidelines are available that address appropriate drug therapy changes, and others are in development. Additionally, a number of clinical resources are emerging to support family physicians in the use of pharmacogenetics. When used appropriately, pharmacogenetic testing can be a practical tool to optimize drug therapy and avoid medication adverse effects.

  17. Pharmacogenetics: Using Genetic Information to Guide Drug Therapy.

    PubMed

    Chang, Ku-Lang; Weitzel, Kristin; Schmidt, Siegfried

    2015-10-01

    Clinical pharmacogenetics, the use of genetic data to guide drug therapy decisions, is beginning to be used for medications commonly prescribed by family physicians. However, clinicians are largely unfamiliar with principles supporting clinical use of this type of data. For example, genetic variability in the cytochrome P450 2D6 drug metabolizing enzyme can alter the clinical effects of some opioid analgesics (e.g., codeine, tramadol), whereas variability in the CYP2C19 enzyme affects the antiplatelet agent clopidogrel. If testing is performed, patients who are ultrarapid or poor metabolizers of CYP2D6 should avoid codeine use (and possibly tramadol, hydrocodone, and oxycodone) because of the potential for increased toxicity or lack of effectiveness. Patients undergoing percutaneous coronary intervention for acute coronary syndromes who are known to be poor metabolizers of CYP2C19 should consider alternate antiplatelet therapy (e.g., ticagrelor, prasugrel). Some guidelines are available that address appropriate drug therapy changes, and others are in development. Additionally, a number of clinical resources are emerging to support family physicians in the use of pharmacogenetics. When used appropriately, pharmacogenetic testing can be a practical tool to optimize drug therapy and avoid medication adverse effects. PMID:26447442

  18. An Improved Hierarchical Genetic Algorithm for Sheet Cutting Scheduling with Process Constraints

    PubMed Central

    Rao, Yunqing; Qi, Dezhong; Li, Jinling

    2013-01-01

    For the first time, an improved hierarchical genetic algorithm for sheet cutting problem which involves n cutting patterns for m non-identical parallel machines with process constraints has been proposed in the integrated cutting stock model. The objective of the cutting scheduling problem is minimizing the weighted completed time. A mathematical model for this problem is presented, an improved hierarchical genetic algorithm (ant colony—hierarchical genetic algorithm) is developed for better solution, and a hierarchical coding method is used based on the characteristics of the problem. Furthermore, to speed up convergence rates and resolve local convergence issues, a kind of adaptive crossover probability and mutation probability is used in this algorithm. The computational result and comparison prove that the presented approach is quite effective for the considered problem. PMID:24489491

  19. An entomologist guide to demystify pseudoreplication: data analysis of field studies with design constraints.

    PubMed

    Chaves, Luis Fernando

    2010-05-01

    Lack of independence, or pseudoreplication, in samples from ecological studies of insects reflects the complexity of working with living organisms: the finite and limited input of individuals, their relatedness (ecological and/or genetic), and the need to group organisms into functional experimental units to estimate population parameters (e.g., cohort replicates). Several decades ago, when the issue of pseudoreplication was first recognized, it was highlighted that mainstream statistical tools were unable to account for the lack of independence. For example, the variability as a result of differences across individuals would be confounded with that of the experimental units where they were observed (e.g., pans for mosquito larvae), whereas both sources of variability now can be separated using modern statistical techniques, such as the linear mixed effects model, that explicitly consider the different scales of variability in a dataset (e.g., mosquitoes and pans). However, the perception of pseudoreplication as a problem without solution remains. This study presents concepts to critically appraise pseudoreplication and the linear mixed effects model as a statistical solution for analyzing data with pseudoreplication, by separating the different sources of variability and thereby generating correct inferences from data gathered in studies with constraints in randomization.

  20. Little effect of seasonal constraints on population genetic structure in eusocial paper wasps

    PubMed Central

    Lengronne, Thibault; Leadbeater, Ellouise; Patalano, Solenn; Dreier, Stephanie; Field, Jeremy; Sumner, Seirian; Keller, Laurent

    2012-01-01

    Climate has long been suggested to affect population genetic structures of eusocial insect societies. For instance, Hamilton [Journal of Theoretical Biology 7 (1964) 17] discusses whether temperate and tropical eusocial insects may show differences in population-level genetic structure and viscosity, and how this might relate to differences in the degree of synchrony in their life cycles or modes of nest founding. Despite the importance of Hamilton's 1964 papers, this specific idea has not been tested in actual populations of wasps, probably due to the paucity of studies on tropical species. Here, we compare colony and population genetic structures in two species of primitively eusocial paper wasps with contrasting ecologies: the tropical species Polistes canadensis and the temperate species P. dominulus. Our results provide important clarifications of Hamilton's discussion. Specifically, we show that the genetic structures of the temperate and tropical species were very similar, indicating that seasonality does not greatly affect population viscosity or inbreeding. For both species, the high genetic differentiation between nests suggests strong selection at the nest level to live with relatives, whereas low population viscosity and low genetic differentiation between nest aggregations might reflect balancing selection to disperse, avoiding competition with relatives. Overall, our study suggests no prevalence of seasonal constraints of the life cycle in affecting the population genetic structure of eusocial paper wasps. These conclusions are likely to apply also to other primitively eusocial insects, such as halictine bees. They also highlight how selection for a kin structure that promotes altruism can override potential effects of ecology in eusocial insects. PMID:23145345

  1. Constraints on Biological Mechanism from Disease Comorbidity Using Electronic Medical Records and Database of Genetic Variants.

    PubMed

    Bagley, Steven C; Sirota, Marina; Chen, Richard; Butte, Atul J; Altman, Russ B

    2016-04-01

    Patterns of disease co-occurrence that deviate from statistical independence may represent important constraints on biological mechanism, which sometimes can be explained by shared genetics. In this work we study the relationship between disease co-occurrence and commonly shared genetic architecture of disease. Records of pairs of diseases were combined from two different electronic medical systems (Columbia, Stanford), and compared to a large database of published disease-associated genetic variants (VARIMED); data on 35 disorders were available across all three sources, which include medical records for over 1.2 million patients and variants from over 17,000 publications. Based on the sources in which they appeared, disease pairs were categorized as having predominant clinical, genetic, or both kinds of manifestations. Confounding effects of age on disease incidence were controlled for by only comparing diseases when they fall in the same cluster of similarly shaped incidence patterns. We find that disease pairs that are overrepresented in both electronic medical record systems and in VARIMED come from two main disease classes, autoimmune and neuropsychiatric. We furthermore identify specific genes that are shared within these disease groups. PMID:27115429

  2. Relaxed Genetic Constraint is Ancestral to the Evolution of Phenotypic Plasticity

    PubMed Central

    Leichty, Aaron R.; Pfennig, David W.; Jones, Corbin D.; Pfennig, Karin S.

    2012-01-01

    Phenotypic plasticity––the capacity of a single genotype to produce different phenotypes in response to varying environmental conditions––is widespread. Yet, whether, and how, plasticity impacts evolutionary diversification is unclear. According to a widely discussed hypothesis, plasticity promotes rapid evolution because genes expressed differentially across different environments (i.e., genes with “biased” expression) experience relaxed genetic constraint and thereby accumulate variation faster than do genes with unbiased expression. Indeed, empirical studies confirm that biased genes evolve faster than unbiased genes in the same genome. An alternative hypothesis holds, however, that the relaxed constraint and faster evolutionary rates of biased genes may be a precondition for, rather than a consequence of, plasticity’s evolution. Here, we evaluated these alternative hypotheses by characterizing evolutionary rates of biased and unbiased genes in two species of frogs that exhibit a striking form of phenotypic plasticity. We also characterized orthologs of these genes in four species of frogs that had diverged from the two plastic species before the plasticity evolved. We found that the faster evolutionary rates of biased genes predated the evolution of the plasticity. Furthermore, biased genes showed greater expression variance than did unbiased genes, suggesting that they may be more dispensable. Phenotypic plasticity may therefore evolve when dispensable genes are co-opted for novel function in environmentally induced phenotypes. Thus, relaxed genetic constraint may be a cause––not a consequence––of the evolution of phenotypic plasticity, and thereby contribute to the evolution of novel traits. PMID:22526866

  3. Unifying genetic canalization, genetic constraint, and genotype-by-environment interaction: QTL by genomic background by environment interaction of flowering time in Boechera stricta.

    PubMed

    Lee, Cheng-Ruei; Anderson, Jill T; Mitchell-Olds, Thomas

    2014-10-01

    Natural populations exhibit substantial variation in quantitative traits. A quantitative trait is typically defined by its mean and variance, and to date most genetic mapping studies focus on loci altering trait means but not (co)variances. For single traits, the control of trait variance across genetic backgrounds is referred to as genetic canalization. With multiple traits, the genetic covariance among different traits in the same environment indicates the magnitude of potential genetic constraint, while genotype-by-environment interaction (GxE) concerns the same trait across different environments. While some have suggested that these three attributes of quantitative traits are different views of similar concepts, it is not yet clear, however, whether they have the same underlying genetic mechanism. Here, we detect quantitative trait loci (QTL) influencing the (co)variance of phenological traits in six distinct environments in Boechera stricta, a close relative of Arabidopsis. We identified nFT as the QTL altering the magnitude of phenological trait canalization, genetic constraint, and GxE. Both the magnitude and direction of nFT's canalization effects depend on the environment, and to our knowledge, this reversibility of canalization across environments has not been reported previously. nFT's effects on trait covariance structure (genetic constraint and GxE) likely result from the variable and reversible canalization effects across different traits and environments, which can be explained by the interaction among nFT, genomic backgrounds, and environmental stimuli. This view is supported by experiments demonstrating significant nFT by genomic background epistatic interactions affecting phenological traits and expression of the candidate gene, FT. In contrast to the well-known canalization gene Hsp90, the case of nFT may exemplify an alternative mechanism: Our results suggest that (at least in traits with major signal integrators such as flowering time) genetic

  4. Flexible Job-Shop Scheduling with Dual-Resource Constraints to Minimize Tardiness Using Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Paksi, A. B. N.; Ma'ruf, A.

    2016-02-01

    In general, both machines and human resources are needed for processing a job on production floor. However, most classical scheduling problems have ignored the possible constraint caused by availability of workers and have considered only machines as a limited resource. In addition, along with production technology development, routing flexibility appears as a consequence of high product variety and medium demand for each product. Routing flexibility is caused by capability of machines that offers more than one machining process. This paper presents a method to address scheduling problem constrained by both machines and workers, considering routing flexibility. Scheduling in a Dual-Resource Constrained shop is categorized as NP-hard problem that needs long computational time. Meta-heuristic approach, based on Genetic Algorithm, is used due to its practical implementation in industry. Developed Genetic Algorithm uses indirect chromosome representative and procedure to transform chromosome into Gantt chart. Genetic operators, namely selection, elitism, crossover, and mutation are developed to search the best fitness value until steady state condition is achieved. A case study in a manufacturing SME is used to minimize tardiness as objective function. The algorithm has shown 25.6% reduction of tardiness, equal to 43.5 hours.

  5. Geographic Variation of Melanisation Patterns in a Hornet Species: Genetic Differences, Climatic Pressures or Aposematic Constraints?

    PubMed Central

    Perrard, Adrien; Arca, Mariangela; Rome, Quentin; Muller, Franck; Tan, Jiangli; Bista, Sanjaya; Nugroho, Hari; Baudoin, Raymond; Baylac, Michel; Silvain, Jean-François; Carpenter, James M.; Villemant, Claire

    2014-01-01

    Coloration of stinging insects is often based on contrasted patterns of light and black pigmentations as a warning signal to predators. However, in many social wasp species, geographic variation drastically modifies this signal through melanic polymorphism potentially driven by different selective pressures. To date, surprisingly little is known about the geographic variation of coloration of social wasps in relation to aposematism and melanism and to genetic and developmental constraints. The main objectives of this study are to improve the description of the colour variation within a social wasp species and to determine which factors are driving this variation. Therefore, we explored the evolutionary history of a polymorphic hornet, Vespa velutina Lepeletier, 1836, using mitochondrial and microsatellite markers, and we analysed its melanic variation using a colour space based on a description of body parts coloration. We found two main lineages within the species and confirmed the previous synonymy of V. auraria Smith, 1852, under V. velutina, differing only by the coloration. We also found that the melanic variation of most body parts was positively correlated, with some segments forming potential colour modules. Finally, we showed that the variation of coloration between populations was not related to their molecular, geographic or climatic differences. Our observations suggest that the coloration patterns of hornets and their geographic variations are determined by genes with an influence of developmental constraints. Our results also highlight that Vespa velutina populations have experienced several convergent evolutions of the coloration, more likely influenced by constraints on aposematism and Müllerian mimicry than by abiotic pressures on melanism. PMID:24740142

  6. Geographic variation of melanisation patterns in a hornet species: genetic differences, climatic pressures or aposematic constraints?

    PubMed

    Perrard, Adrien; Arca, Mariangela; Rome, Quentin; Muller, Franck; Tan, Jiangli; Bista, Sanjaya; Nugroho, Hari; Baudoin, Raymond; Baylac, Michel; Silvain, Jean-François; Carpenter, James M; Villemant, Claire

    2014-01-01

    Coloration of stinging insects is often based on contrasted patterns of light and black pigmentations as a warning signal to predators. However, in many social wasp species, geographic variation drastically modifies this signal through melanic polymorphism potentially driven by different selective pressures. To date, surprisingly little is known about the geographic variation of coloration of social wasps in relation to aposematism and melanism and to genetic and developmental constraints. The main objectives of this study are to improve the description of the colour variation within a social wasp species and to determine which factors are driving this variation. Therefore, we explored the evolutionary history of a polymorphic hornet, Vespa velutina Lepeletier, 1836, using mitochondrial and microsatellite markers, and we analysed its melanic variation using a colour space based on a description of body parts coloration. We found two main lineages within the species and confirmed the previous synonymy of V. auraria Smith, 1852, under V. velutina, differing only by the coloration. We also found that the melanic variation of most body parts was positively correlated, with some segments forming potential colour modules. Finally, we showed that the variation of coloration between populations was not related to their molecular, geographic or climatic differences. Our observations suggest that the coloration patterns of hornets and their geographic variations are determined by genes with an influence of developmental constraints. Our results also highlight that Vespa velutina populations have experienced several convergent evolutions of the coloration, more likely influenced by constraints on aposematism and Müllerian mimicry than by abiotic pressures on melanism. PMID:24740142

  7. Geographic variation of melanisation patterns in a hornet species: genetic differences, climatic pressures or aposematic constraints?

    PubMed

    Perrard, Adrien; Arca, Mariangela; Rome, Quentin; Muller, Franck; Tan, Jiangli; Bista, Sanjaya; Nugroho, Hari; Baudoin, Raymond; Baylac, Michel; Silvain, Jean-François; Carpenter, James M; Villemant, Claire

    2014-01-01

    Coloration of stinging insects is often based on contrasted patterns of light and black pigmentations as a warning signal to predators. However, in many social wasp species, geographic variation drastically modifies this signal through melanic polymorphism potentially driven by different selective pressures. To date, surprisingly little is known about the geographic variation of coloration of social wasps in relation to aposematism and melanism and to genetic and developmental constraints. The main objectives of this study are to improve the description of the colour variation within a social wasp species and to determine which factors are driving this variation. Therefore, we explored the evolutionary history of a polymorphic hornet, Vespa velutina Lepeletier, 1836, using mitochondrial and microsatellite markers, and we analysed its melanic variation using a colour space based on a description of body parts coloration. We found two main lineages within the species and confirmed the previous synonymy of V. auraria Smith, 1852, under V. velutina, differing only by the coloration. We also found that the melanic variation of most body parts was positively correlated, with some segments forming potential colour modules. Finally, we showed that the variation of coloration between populations was not related to their molecular, geographic or climatic differences. Our observations suggest that the coloration patterns of hornets and their geographic variations are determined by genes with an influence of developmental constraints. Our results also highlight that Vespa velutina populations have experienced several convergent evolutions of the coloration, more likely influenced by constraints on aposematism and Müllerian mimicry than by abiotic pressures on melanism.

  8. Constraints to Genetic Exchange Support Gene Coadaptation in a Tripartite RNA Virus

    PubMed Central

    Escriu, Fernando; Fraile, Aurora; García-Arenal, Fernando

    2007-01-01

    Genetic exchange by recombination, or reassortment of genomic segments, has been shown to be an important process in RNA virus evolution, resulting often in important phenotypic changes affecting host range and virulence. However, data from numerous systems indicate that reassortant or recombinant genotypes could be selected against in virus populations and suggest that there is coadaptation among viral genes. Little is known about the factors affecting the frequency of reassortants and recombinants along the virus life cycle. We have explored this issue by estimating the frequency of reassortant and recombinant genotypes in experimental populations of Cucumber mosaic virus derived from mixed infections with four different pairs of isolates that differed in about 12% of their nucleotide sequence. Genetic composition of progeny populations were analyzed at various steps of the virus life cycle during host colonization: infection of leaf cells, cell-to-cell movement within the inoculated leaf, encapsidation of progeny genomes, and systemic movement to upper noninoculated leaves. Results indicated that reassortant frequencies do not correspond to random expectations and that selection operates against reassortant genotypes. The intensity of selection, estimated through the use of log-linear models, increased as host colonization progressed. No recombinant was detected in any progeny. Hence, results showed the existence of constraints to genetic exchange linked to various steps of the virus life cycle, so that genotypes with heterologous gene combinations were less fit and disappeared from the population. These results contribute to explain the low frequency of recombinants and reassortants in natural populations of many viruses, in spite of high rates of genetic exchange. More generally, the present work supports the hypothesis of coadaptation of gene complexes within the viral genomes. PMID:17257060

  9. Using Genetic Testing to Guide Therapeutic Decisions in Cardiomyopathy

    PubMed Central

    Lakdawala, Neal K

    2013-01-01

    Opinion statement Genetic analysis of human cardiomyopathy has rapidly transitioned from a strictly research endeavor to a diagnostic tool readily available to clinicians across the globe. In contemporary practice, genetic testing improves the efficiency of family evaluations and clarifies the etiology of ambiguous clinical presentations. The great promise of genetic diagnosis is to enable preventative therapies for individuals at high risk of future disease development, a strategy that is under active clinical investigation. However, in the present and future, careful interpretation of DNA sequence variation is critical, and can be ensured by referral to a specialized cardiovascular genetics clinic. PMID:23794152

  10. The Life Course Perspective: a Guide for Genetic Counselors.

    PubMed

    Hamilton, Rebekah J; Innella, Nancy A; Bounds, Dawn T

    2016-02-01

    This is the first article in a two part series about utilizing the life course perspective (LCP) in genetic counseling. LCP can be a useful tool for genetic counselors when counseling people with a known genetic mutation. Previous theories such as Protection Motivation Theory (PMT) and Common Sense Model of Self-Regulation (CSMSR) examine current reactions to a positive genetic test result. LCP extends beyond the current time to explore temporal and contextual elements of the experience. A review of research revealed, LCP has been used to study the perspective of caregivers of people with Alzheimer's disease, referral for a family history of breast cancer, Mexican American caregivers of older adult, social class and cancer incidence and cancer and the sense of mastery. Incorporating LCP into a study explaining the experiences of people living with a positive test result for a genetic mutation such as the BRCA mutation provides a comprehensive exploration of this experience.

  11. Introductory Guide to the Statistics of Molecular Genetics

    ERIC Educational Resources Information Center

    Eley, Thalia C.; Rijsdijk, Fruhling

    2005-01-01

    Background: This introductory guide presents the main two analytical approaches used by molecular geneticists: linkage and association. Methods: Traditional linkage and association methods are described, along with more recent advances in methodologies such as those using a variance components approach. Results: New methods are being developed all…

  12. The Hitchhiker’s Guide to Xenopus Genetics

    PubMed Central

    Abu-Daya, Anita; Khokha, Mustafa K.; Zimmerman, Lyle B.

    2012-01-01

    Summary A decade after the human genome sequence, most vertebrate gene functions remain poorly understood, limiting benefits to human health from rapidly advancing genomic technologies. Systematic in vivo functional analysis is ideally suited to the experimentally accessible Xenopus embryo, which combines embryological accessibility with a broad range of transgenic, biochemical and gain-of-function assays. The diploid X. tropicalis adds loss-of-function genetics and enhanced genomics to this repertoire. In the last decade diverse phenotypes have been recovered from genetic screens, mutations have been cloned, and reverse genetics in the form of TILLING and targeted gene editing have been established. Simple haploid genetics and gynogenesis and the very large number of embryos produced streamline screening and mapping. Improved genomic resources and the revolution in high-throughput sequencing are transforming mutation cloning and reverse genetic approaches. The combination of loss-of-function mutant backgrounds with the diverse array of conventional Xenopus assays offers a uniquely flexible platform for analysis of gene function in vertebrate development. PMID:22344745

  13. A Guide to Selected National Genetic Voluntary Organizations.

    ERIC Educational Resources Information Center

    National Center for Education in Maternal and Child Health, Washington, DC.

    The directory lists mutual support groups concerned with the medical and psychosocial impacts of genetic disorders and birth defects on affected individuals and families. Each organization included is dedicated to the ongoing emotional, practical, and financial needs of these populations. Entries are categorized by disorder, including: general,…

  14. A Guide to Selected National Genetic Voluntary Organizations.

    ERIC Educational Resources Information Center

    National Center for Education in Maternal and Child Health, Washington, DC.

    The directory lists approximately 120 mutual support groups concerned with the medical and psychological impacts of genetic disorders and birth defects on individuals and their families. The groups are dedicated to serving the ongoing emotional, practical, and financial needs of these populations. The entries are arranged alphabetically and…

  15. Effects of Hybridization and Evolutionary Constraints on Secondary Metabolites: The Genetic Architecture of Phenylpropanoids in European Populus Species

    PubMed Central

    Caseys, Celine; Stritt, Christoph; Glauser, Gaetan; Blanchard, Thierry; Lexer, Christian

    2015-01-01

    The mechanisms responsible for the origin, maintenance and evolution of plant secondary metabolite diversity remain largely unknown. Decades of phenotypic studies suggest hybridization as a key player in generating chemical diversity in plants. Knowledge of the genetic architecture and selective constraints of phytochemical traits is key to understanding the effects of hybridization on plant chemical diversity and ecological interactions. Using the European Populus species P. alba (White poplar) and P. tremula (European aspen) and their hybrids as a model, we examined levels of inter- and intraspecific variation, heritabilities, phenotypic correlations, and the genetic architecture of 38 compounds of the phenylpropanoid pathway measured by liquid chromatography and mass spectrometry (UHPLC-MS). We detected 41 quantitative trait loci (QTL) for chlorogenic acids, salicinoids and flavonoids by genetic mapping in natural hybrid crosses. We show that these three branches of the phenylpropanoid pathway exhibit different geographic patterns of variation, heritabilities, and genetic architectures, and that they are affected differently by hybridization and evolutionary constraints. Flavonoid abundances present high species specificity, clear geographic structure, and strong genetic determination, contrary to salicinoids and chlorogenic acids. Salicinoids, which represent important defence compounds in Salicaceae, exhibited pronounced genetic correlations on the QTL map. Our results suggest that interspecific phytochemical differentiation is concentrated in downstream sections of the phenylpropanoid pathway. In particular, our data point to glycosyltransferase enzymes as likely targets of rapid evolution and interspecific differentiation in the ‘model forest tree’ Populus. PMID:26010156

  16. Initialization Method for Grammar-Guided Genetic Programming

    NASA Astrophysics Data System (ADS)

    García-Arnau, M.; Manrique, D.; Ríos, J.; Rodríguez-Patón, A.

    This paper proposes a new tree-generation algorithm for grammarguided genetic programming that includes a parameter to control the maximum size of the trees to be generated. An important feature of this algorithm is that the initial populations generated are adequately distributed in terms of tree size and distribution within the search space. Consequently, genetic programming systems starting from the initial populations generated by the proposed method have a higher convergence speed. Two different problems have been chosen to carry out the experiments: a laboratory test involving searching for arithmetical equalities and the real-world task of breast cancer prognosis. In both problems, comparisons have been made to another five important initialization methods.

  17. Users guide to the PGAPack parallel genetic algorithm library

    SciTech Connect

    Levine, D.

    1996-01-01

    PGAPack is a parallel genetic algorithm library that is intended to provide most capabilities desired in a genetic algorithm package, in an integrated, seamless, and portable manner. Key features of PGAPack are as follows: Ability to be called from Fortran or C. Executable on uniprocessors, multiprocessors, multicomputers, and workstation networks. Binary-, integer-, real-, and character-valued native data types. Object-oriented data structure neutral design. Parameterized population replacement. Multiple choices for selection, crossover, and mutation operators. Easy integration of hill-climbing heuristics. Easy-to-use interface for novice and application users. Multiple levels of access for expert users. Full extensibility to support custom operators and new data types. Extensive debugging facilities. Large set of example problems.

  18. Specific immunotherapy by genetically engineered APCs: the "guided missile" strategy.

    PubMed

    Wu, B; Wu, J M; Miagkov, A; Adams, R N; Levitsky, H I; Drachman, D B

    2001-04-01

    We tested the hypothesis that APCs genetically engineered to present an Ag and to express Fas ligand (FasL) simultaneously can target and eliminate Ag-specific T cells. Transgenic T cells specific for influenza hemagglutinin (HA) were used as targets. We prepared recombinant vaccinia virus vectors (VVV) to transfer the gene constructs individually or simultaneously into APCs. We prevented unwanted viral replication by attenuating the VVVs with psoralen-UV light treatment. For presentation of the HA Ag, APCs were transduced with cDNA for HA flanked by sequences of the lysosome-associated membrane protein that direct efficient processing and presentation of the Ag by APCs. As a "warhead" for the APCs, we transduced them with the gene for FasL, which induces apoptosis of Fas-expressing activated T cells. To protect the transduced APCs from self-destruction by FasL, we transferred cDNA for a truncated form of Fas-associated death domain, which inhibits Fas-mediated cell death. Our results show that the engineered APCs effectively expressed the genes of interest. APCs transduced with VVV carrying all three gene constructs specifically killed HA-transgenic T cells in culture. Coculture with T cells specific for an unrelated Ag (OVA) had no significant effect. Our in vitro findings show that APCs can be genetically engineered to target and kill Ag-specific T cells and represent a promising novel strategy for the specific treatment of autoimmune diseases. PMID:11254740

  19. Can genetic testing guide treatment in breast cancer?

    PubMed

    Tutt, Andrew; Ashworth, Alan

    2008-12-01

    In the last 15 years, our understanding of genes that predispose to breast cancer has increased enormously. Germline alleles have been identified that have a modest effect on the risk of breast cancer, but there remain only a handful of genes in which mutation substantially elevates the risk of breast cancer. These include BRCA1, BRCA2, TP53 and PTEN. Whilst breast cancer occurring in patients in Li-Fraumeni and Cowden's syndrome families is of great importance, the more frequent scenario is that of women, or indeed of men, presenting with breast cancer with an underlying germline mutation in BRCA1 or BRCA2. Should these individuals be treated differently because they have had a breast cancer or are at risk of the disease because of a BRCA1 or BRCA2 mutation? In this review, we consider whether BRCA1 or BRCA2 mutation influences the choice of breast screening and breast cancer prevention strategies. Furthermore, for women with an established breast cancer whether their mutation directly influences (1) baseline prognosis, (2) the results of local surgical and radiation therapy, (3) the benefits from adjuvant systemic therapy and finally (4) whether selection or avoidance of particular systemic agents is guided by the presence of a BRCA1 or BRCA2 germline mutation?

  20. The rank ordering of genotypic fitness values predicts genetic constraint on natural selection on landscapes lacking sign epistasis.

    PubMed

    Weinreich, Daniel M

    2005-11-01

    Sewall Wright's genotypic fitness landscape makes explicit one mechanism by which epistasis for fitness can constrain evolution by natural selection. Wright distinguished between landscapes possessing multiple fitness peaks and those with only a single peak and emphasized that the former class imposes substantially greater constraint on natural selection. Here I present novel formalism that more finely partitions the universe of possible fitness landscapes on the basis of the rank ordering of their genotypic fitness values. In this report I focus on fitness landscapes lacking sign epistasis (i.e., landscapes that lack mutations the sign of whose fitness effect varies epistatically), which constitute a subset of Wright's single peaked landscapes. More than one fitness rank ordering lacking sign epistasis exists for L > 2 (where L is the number of interacting loci), and I find that a highly statistically significant effect exists between landscape membership in fitness rank-ordering partition and two different proxies for genetic constraint, even within this subset of landscapes. This statistical association is robust to population size, permitting general inferences about some of the characteristics of fitness rank orderings responsible for genetic constraint on natural selection. PMID:16079241

  1. Rapid construction of insulated genetic circuits via synthetic sequence-guided isothermal assembly

    SciTech Connect

    Torella, JP; Boehm, CR; Lienert, F; Chen, JH; Way, JC; Silver, PA

    2013-12-28

    In vitro recombination methods have enabled one-step construction of large DNA sequences from multiple parts. Although synthetic biological circuits can in principle be assembled in the same fashion, they typically contain repeated sequence elements such as standard promoters and terminators that interfere with homologous recombination. Here we use a computational approach to design synthetic, biologically inactive unique nucleotide sequences (UNSes) that facilitate accurate ordered assembly. Importantly, our designed UNSes make it possible to assemble parts with repeated terminator and insulator sequences, and thereby create insulated functional genetic circuits in bacteria and mammalian cells. Using UNS-guided assembly to construct repeating promoter-gene-terminator parts, we systematically varied gene expression to optimize production of a deoxychromoviridans biosynthetic pathway in Escherichia coli. We then used this system to construct complex eukaryotic AND-logic gates for genomic integration into embryonic stem cells. Construction was performed by using a standardized series of UNS-bearing BioBrick-compatible vectors, which enable modular assembly and facilitate reuse of individual parts. UNS-guided isothermal assembly is broadly applicable to the construction and optimization of genetic circuits and particularly those requiring tight insulation, such as complex biosynthetic pathways, sensors, counters and logic gates.

  2. A Study of Penalty Function Methods for Constraint Handling with Genetic Algorithm

    NASA Technical Reports Server (NTRS)

    Ortiz, Francisco

    2004-01-01

    COMETBOARDS (Comparative Evaluation Testbed of Optimization and Analysis Routines for Design of Structures) is a design optimization test bed that can evaluate the performance of several different optimization algorithms. A few of these optimization algorithms are the sequence of unconstrained minimization techniques (SUMT), sequential linear programming (SLP) and the sequential quadratic programming techniques (SQP). A genetic algorithm (GA) is a search technique that is based on the principles of natural selection or "survival of the fittest". Instead of using gradient information, the GA uses the objective function directly in the search. The GA searches the solution space by maintaining a population of potential solutions. Then, using evolving operations such as recombination, mutation and selection, the GA creates successive generations of solutions that will evolve and take on the positive characteristics of their parents and thus gradually approach optimal or near-optimal solutions. By using the objective function directly in the search, genetic algorithms can be effectively applied in non-convex, highly nonlinear, complex problems. The genetic algorithm is not guaranteed to find the global optimum, but it is less likely to get trapped at a local optimum than traditional gradient-based search methods when the objective function is not smooth and generally well behaved. The purpose of this research is to assist in the integration of genetic algorithm (GA) into COMETBOARDS. COMETBOARDS cast the design of structures as a constrained nonlinear optimization problem. One method used to solve constrained optimization problem with a GA to convert the constrained optimization problem into an unconstrained optimization problem by developing a penalty function that penalizes infeasible solutions. There have been several suggested penalty function in the literature each with there own strengths and weaknesses. A statistical analysis of some suggested penalty functions

  3. Genetic algorithms-based inversion of multimode guided waves for cortical bone characterization

    NASA Astrophysics Data System (ADS)

    Bochud, N.; Vallet, Q.; Bala, Y.; Follet, H.; Minonzio, J.-G.; Laugier, P.

    2016-10-01

    Recent progress in quantitative ultrasound has exploited the multimode waveguide response of long bones. Measurements of the guided modes, along with suitable waveguide modeling, have the potential to infer strength-related factors such as stiffness (mainly determined by cortical porosity) and cortical thickness. However, the development of such model-based approaches is challenging, in particular because of the multiparametric nature of the inverse problem. Current estimation methods in the bone field rely on a number of assumptions for pairing the incomplete experimental data with the theoretical guided modes (e.g. semi-automatic selection and classification of the data). The availability of an alternative inversion scheme that is user-independent is highly desirable. Thus, this paper introduces an efficient inversion method based on genetic algorithms using multimode guided waves, in which the mode-order is kept blind. Prior to its evaluation on bone, our proposal is validated using laboratory-controlled measurements on isotropic plates and bone-mimicking phantoms. The results show that the model parameters (i.e. cortical thickness and porosity) estimated from measurements on a few ex vivo human radii are in good agreement with the reference values derived from x-ray micro-computed tomography. Further, the cortical thickness estimated from in vivo measurements at the third from the distal end of the radius is in good agreement with the values delivered by site-matched high-resolution x-ray peripheral computed tomography.

  4. Experimental evolution for generalists and specialists reveals multivariate genetic constraints on thermal reaction norms.

    PubMed

    Berger, D; Walters, R J; Blanckenhorn, W U

    2014-09-01

    Theory predicts the emergence of generalists in variable environments and antagonistic pleiotropy to favour specialists in constant environments, but empirical data seldom support such generalist-specialist trade-offs. We selected for generalists and specialists in the dung fly Sepsis punctum (Diptera: Sepsidae) under conditions that we predicted would reveal antagonistic pleiotropy and multivariate trade-offs underlying thermal reaction norms for juvenile development. We performed replicated laboratory evolution using four treatments: adaptation at a hot (31 °C) or a cold (15 °C) temperature, or under regimes fluctuating between these temperatures, either within or between generations. After 20 generations, we assessed parental effects and genetic responses of thermal reaction norms for three correlated life-history traits: size at maturity, juvenile growth rate and juvenile survival. We find evidence for antagonistic pleiotropy for performance at hot and cold temperatures, and a temperature-mediated trade-off between juvenile survival and size at maturity, suggesting that trade-offs associated with environmental tolerance can arise via intensified evolutionary compromises between genetically correlated traits. However, despite this antagonistic pleiotropy, we found no support for the evolution of increased thermal tolerance breadth at the expense of reduced maximal performance, suggesting low genetic variance in the generalist-specialist dimension.

  5. Genetic mechanisms and constraints governing the evolution of correlated traits in drosophilid flies.

    PubMed

    Gompel, Nicolas; Carroll, Sean B

    2003-08-21

    Some morphological traits differ greatly between related species, but it is not clear whether diversity evolves through changes in the same genes and whether similar, independent (that is, convergent) changes occur by the same mechanism. Pigmentation in fruitflies presents an attractive opportunity to explore these issues because pigmentation patterns are diverse, similar patterns have arisen in independent clades, and numerous genes governing their formation have been identified in Drosophila melanogaster. Here we show that both evolutionary diversification and convergence can be due to evolution at the same locus, by comparing abdominal pigmentation and trichome patterns and the expression of Bric-à-brac2 (Bab2), which regulates both traits in D. melanogaster, in 13 species representing the major clades of the subfamily Drosophilinae. Modifications of Bab2 expression are frequently correlated with diverse pigmentation and trichome patterns that evolved independently in multiple lineages. In a few species, Bab2 expression is not correlated with changes in pigmentation but is correlated with a conserved pattern of trichomes, indicating that this locus can be circumvented to evolve new patterns when a correlated trait is under different constraints.

  6. DeMAID/GA USER'S GUIDE Design Manager's Aid for Intelligent Decomposition with a Genetic Algorithm

    NASA Technical Reports Server (NTRS)

    Rogers, James L.

    1996-01-01

    Many companies are looking for new tools and techniques to aid a design manager in making decisions that can reduce the time and cost of a design cycle. One tool that is available to aid in this decision making process is the Design Manager's Aid for Intelligent Decomposition (DeMAID). Since the initial release of DEMAID in 1989, numerous enhancements have been added to aid the design manager in saving both cost and time in a design cycle. The key enhancement is a genetic algorithm (GA) and the enhanced version is called DeMAID/GA. The GA orders the sequence of design processes to minimize the cost and time to converge to a solution. These enhancements as well as the existing features of the original version of DEMAID are described. Two sample problems are used to show how these enhancements can be applied to improve the design cycle. This report serves as a user's guide for DeMAID/GA.

  7. Large-Scale Single-Guide RNA Library Construction and Use for Genetic Screens

    PubMed Central

    Wang, Tim; Lander, Eric S.; Sabatini, David M.

    2016-01-01

    The ability to systematically disrupt genes serves as a powerful tool for understanding their function. The programmable Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system enables efficient targeting of large numbers of genes through the use of single-guide RNA (sgRNA) libraries. In cultured mammalian cells, collections of knockout mutants can be readily generated via transduction of Cas9/sgRNA lentiviral pools, screened for a phenotype of interest, and tracked using high-throughput DNA sequencing. This technique represents the first general method for undertaking systematic loss-of-function genetic screens in mammalian cells. In this chapter, we outline the steps for conducting CRISPR-based screens from the initial library design to final data analysis and provide guidelines for developing an appropriate screening strategy. PMID:26933254

  8. Mechanism-guided library design and dual genetic selection of synthetic OFF riboswitches.

    PubMed

    Muranaka, Norihito; Abe, Koichi; Yokobayashi, Yohei

    2009-09-21

    After the recent discovery of bacterial riboswitches, synthetic riboswitches have been engineered by using natural and artificial RNA aptamers. In contrast to natural riboswitches, the majority of synthetic riboswitches in bacteria reported to date are ON switches that activate gene expression in response to the aptamer ligand. In this study, we adopted a mechanism-guided approach to design libraries predisposed to contain OFF riboswitches that respond to thiamine pyrophosphate (TPP). The first library design exploited a pseudo-Shine-Dalgarno (SD) sequence located near the 3'-end of the TPP aptamer, which would be less accessible to the ribosome when the aptamer is bound to TPP. In the second library, an SD sequence was strategically placed in the aptamer's P1 stem, which is stabilized upon ligand binding. OFF riboswitches were obtained by dual genetic selection of these libraries. The results underscore the importance of effective library design to achieve desired riboswitch functions. PMID:19658147

  9. Lakeview uranium area, Lake County, Oregon - constraints on genetic modelling from a district-scale perspective

    SciTech Connect

    Weissenburger, K.W.

    1984-01-01

    Extent-of-outcrop geologic mapping (1:12,000) on the Cox Flat 7.5-minute quadrangle establishes the stratigraphy and structure near the White King uranium mine, about 25 km northwest of Lakeview, Lake County, Oregon. Bedrock includes an Oligocene andesitic volcanic/sedimentary section, four late Oligocene rhyodacitic ignimbrite sequences, a late Oligocene/Miocene tuffaceous section, locally thick early to late Miocene basaltic flows, and an interbedded sequence of late Miocene (about 7-8 Ma old) felsic tuffs and thin basalt flows. Relatively intense down-to-the northeast normal faulting and southwestward stratal tilting resulted from a pre-Basin-and-Range extensional tectonic regime with an ENE least-principal stress orientation. This faulting and tilting began after the late Oligocene ignimbrite volcanism and before the spread of Coleman Rim-equivalent basalt flows. The interpreted geology constrains genetic models, resource estimates, and exploration strategies for uranium occurrences in the Lakeview area. Fault- and fracture-controlled hydrothermal uranium deposits are restricted to favorable stratigraphic horizons of the Miocene section with the important exception of porous and permeable upper portions of the late Oligocene section. Previous models have stressed the importance of intrusive rhyolite plug domes as sources of uranium and/or heat in ore genesis and targeted exploration efforts at dome contacts. Mass balance and other arguments show that an association with rhyolite domes is not a necessary criterion for ore formation or exploration.

  10. Genetic Conditions: A Resource Book and Instructional Guide to Human Heredity and Birth Defects for Kindergarten Through Adult Education.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento.

    Designed for administrators, teachers, school nurses, and others involved in health education for kindergarten through adult education, the resource guide provides curriculum ideas for instruction in genetic conditions, heredity, and birth defects. Student learning objectives, content information, learning activities, and evaluation methods are…

  11. 75 FR 36445 - Draft Regulatory Guide, DG-4018, “Constraint on Releases of Airborne Radioactive Materials To the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-25

    ... Period. SUMMARY: On April 20, 2010 (75 FR 20645), the U. S. Nuclear Regulatory Commission (NRC) published... ADAMS Accession Number ML092600090. SUPPLEMENTARY INFORMATION: On April 20, 2010 (75 FR 20645), the NRC... Environment for Licensees Other Than Power Reactors,'' Proposed Revision 1 of Regulatory Guide 4.20;...

  12. Constraints, independence, and evolution of thermal plasticity: probing genetic architecture of long- and short-term thermal acclimation.

    PubMed

    Gerken, Alison R; Eller, Olivia C; Hahn, Daniel A; Morgan, Theodore J

    2015-04-01

    Seasonal and daily thermal variation can limit species distributions because of physiological tolerances. Low temperatures are particularly challenging for ectotherms, which use both basal thermotolerance and acclimation, an adaptive plastic response, to mitigate thermal stress. Both basal thermotolerance and acclimation are thought to be important for local adaptation and persistence in the face of climate change. However, the evolutionary independence of basal and plastic tolerances remains unclear. Acclimation can occur over longer (seasonal) or shorter (hours to days) time scales, and the degree of mechanistic overlap is unresolved. Using a midlatitude population of Drosophila melanogaster, we show substantial heritable variation in both short- and long-term acclimation. Rapid cold hardening (short-term plasticity) and developmental acclimation (long-term plasticity) are positively correlated, suggesting shared mechanisms. However, there are independent components of these traits, because developmentally acclimated flies respond positively to short-term acclimation. A strong negative correlation between basal cold tolerance and developmental acclimation suggests that basal cold tolerance may constrain developmental acclimation, whereas a weaker negative correlation between basal cold tolerance and short-term acclimation suggests less constraint. Using genome-wide association mapping, we show the genetic architecture of rapid cold hardening and developmental acclimation responses are nonoverlapping at the SNP and corresponding gene level. However, genes associated with each trait share functional similarities, including genes involved in apoptosis and autophagy, cytoskeletal and membrane structural components, and ion binding and transport. These results indicate substantial opportunity for short-term and long-term acclimation responses to evolve separately from each other and for short-term acclimation to evolve separately from basal thermotolerance.

  13. Multi-View Budgeted Learning under Label and Feature Constraints Using Label-Guided Graph-Based Regularization

    SciTech Connect

    Symons, Christopher T; Arel, Itamar

    2011-01-01

    Budgeted learning under constraints on both the amount of labeled information and the availability of features at test time pertains to a large number of real world problems. Ideas from multi-view learning, semi-supervised learning, and even active learning have applicability, but a common framework whose assumptions fit these problem spaces is non-trivial to construct. We leverage ideas from these fields based on graph regularizers to construct a robust framework for learning from labeled and unlabeled samples in multiple views that are non-independent and include features that are inaccessible at the time the model would need to be applied. We describe examples of applications that fit this scenario, and we provide experimental results to demonstrate the effectiveness of knowledge carryover from training-only views. As learning algorithms are applied to more complex applications, relevant information can be found in a wider variety of forms, and the relationships between these information sources are often quite complex. The assumptions that underlie most learning algorithms do not readily or realistically permit the incorporation of many of the data sources that are available, despite an implicit understanding that useful information exists in these sources. When multiple information sources are available, they are often partially redundant, highly interdependent, and contain noise as well as other information that is irrelevant to the problem under study. In this paper, we are focused on a framework whose assumptions match this reality, as well as the reality that labeled information is usually sparse. Most significantly, we are interested in a framework that can also leverage information in scenarios where many features that would be useful for learning a model are not available when the resulting model will be applied. As with constraints on labels, there are many practical limitations on the acquisition of potentially useful features. A key difference in the

  14. Space tug thermal control equipment thermal requirements, characteristics, and constraints catalogue: Users guide. [spacecraft thermal control components

    NASA Technical Reports Server (NTRS)

    Ward, T. L.

    1974-01-01

    This manual details the input instructions to the data bank, and explanation of the program and its output. The data bank was developed in satisfaction of two of the study tasks, the equipment thermal requirement catalog and the equipment characteristics and constraints catalog. The data bank contains 109 components within space tug avionics system. Other systems were not included in the data bank due to the available information, however, with some program modification, other systems could be incorporated into the data bank program. The data bank was developed and checked out and is compatible with the Univac 1108, and the CDC 6500 operating systems. The data contained in the data bank is general in content with emphasis on the component thermal design. The data is applicable to any spacecraft program where the components contained in the data bank can be applied in satisfaction of the system and subsystem requirements.

  15. On the use of genetic algorithm to optimize industrial assets lifecycle management under safety and budget constraints

    SciTech Connect

    Lonchampt, J.; Fessart, K.

    2013-07-01

    The purpose of this paper is to describe the method and tool dedicated to optimize investments planning for industrial assets. These investments may either be preventive maintenance tasks, asset enhancements or logistic investments such as spare parts purchases. The two methodological points to investigate in such an issue are: 1. The measure of the profitability of a portfolio of investments 2. The selection and planning of an optimal set of investments 3. The measure of the risk of a portfolio of investments The measure of the profitability of a set of investments in the IPOP tool is synthesised in the Net Present Value indicator. The NPV is the sum of the differences of discounted cash flows (direct costs, forced outages...) between the situations with and without a given investment. These cash flows are calculated through a pseudo-Markov reliability model representing independently the components of the industrial asset and the spare parts inventories. The component model has been widely discussed over the years but the spare part model is a new one based on some approximations that will be discussed. This model, referred as the NPV function, takes for input an investments portfolio and gives its NPV. The second issue is to optimize the NPV. If all investments were independent, this optimization would be an easy calculation, unfortunately there are two sources of dependency. The first one is introduced by the spare part model, as if components are indeed independent in their reliability model, the fact that several components use the same inventory induces a dependency. The second dependency comes from economic, technical or logistic constraints, such as a global maintenance budget limit or a safety requirement limiting the residual risk of failure of a component or group of component, making the aggregation of individual optimum not necessary feasible. The algorithm used to solve such a difficult optimization problem is a genetic algorithm. After a description

  16. Specific immunotherapy of experimental myasthenia by genetically engineered APCs: the "guided missile" strategy.

    PubMed

    Drachman, D B; Wu, J-M; Miagkov, A; Williams, M A; Adams, R N; Wu, B

    2003-09-01

    Although treatment of MG with general immunosuppressive agents is often effective, it has important drawbacks, including suppression of the immune system as a whole, with the risks of infection and neoplasia, and numerous other adverse side effects. Ideally, treatment of MG should eliminate the specific pathogenic autoimmune response to AChR, without otherwise suppressing the immune system or producing other adverse side effects. Although antibodies to AChR are directly responsible for the loss of AChRs at neuromuscular junctions in MG, the AChR antibody response is T cell-dependent, and immunotherapy directed at T cells can abrogate the autoantibody response, with resulting benefit. As in other autoimmune diseases, the T cell response in MG is highly heterogeneous. The design of specific immunotherapy must take this heterogeneity into account and target the entire repertoire of AChR-specific T cells. We describe our investigation of a novel strategy for specific immunotherapy of MG, involving gene transfer to convert antigen-presenting cells (APCs) to "guided missiles" that target AChR-specific T cells, and that induce apoptosis and elimination of those T cells. This strategy uses the ability of APCs from a given individual to present the entire spectrum of AChR epitopes unique for that individual, and thereby to target the entire repertoire of antigen-specific T cells of the same individual. Using viral vectors, we have genetically engineered the APCs to process and present the most important domain of the AChR molecule, and to express a "warhead" of Fas ligand (FasL) to eliminate the activated AChR-specific T cells with which they interact. Our results show that the APCs express the appropriate gene products, and effectively and specifically eliminate AChR-specific T cells by the Fas/FasL pathway, while sparing T cells of other specificities. PMID:14592923

  17. DIAGNOSIS-GUIDED METHOD FOR IDENTIFYING MULTI-MODALITY NEUROIMAGING BIOMARKERS ASSOCIATED WITH GENETIC RISK FACTORS IN ALZHEIMER'S DISEASE.

    PubMed

    Hao, Xiaoke; Yan, Jingwen; Yao, Xiaohui; Risacher, Shannon L; Saykin, Andrew J; Zhang, Daoqiang; Shen, Li

    2016-01-01

    Many recent imaging genetic studies focus on detecting the associations between genetic markers such as single nucleotide polymorphisms (SNPs) and quantitative traits (QTs). Although there exist a large number of generalized multivariate regression analysis methods, few of them have used diagnosis information in subjects to enhance the analysis performance. In addition, few of models have investigated the identification of multi-modality phenotypic patterns associated with interesting genotype groups in traditional methods. To reveal disease-relevant imaging genetic associations, we propose a novel diagnosis-guided multi-modality (DGMM) framework to discover multi-modality imaging QTs that are associated with both Alzheimer's disease (AD) and its top genetic risk factor (i.e., APOE SNP rs429358). The strength of our proposed method is that it explicitly models the priori diagnosis information among subjects in the objective function for selecting the disease-relevant and robust multi-modality QTs associated with the SNP. We evaluate our method on two modalities of imaging phenotypes, i.e., those extracted from structural magnetic resonance imaging (MRI) data and fluorodeoxyglucose positron emission tomography (FDG-PET) data in the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. The experimental results demonstrate that our proposed method not only achieves better performances under the metrics of root mean squared error and correlation coefficient but also can identify common informative regions of interests (ROIs) across multiple modalities to guide the disease-induced biological interpretation, compared with other reference methods.

  18. The 2005 USDA Food Guide Pyramid is associated with more adequate nutrient intakes within energy constraints than the 1992 Pyramid.

    PubMed

    Gao, Xiang; Wilde, Parke E; Lichtenstein, Alice H; Tucker, Katherine L

    2006-05-01

    The USDA issued the Food Guide Pyramid (FGP) to help Americans choose healthy diets. We examined whether adherence to the 1992 and 2005 FGP was associated with moderate energy and adequate nutrient intakes. We used data for 2138 men and 2213 women > 18 y old, from the 2001-2002 U.S. National Health and Nutrition Examination Survey (NHANES). Quadratic programming was used to generate diets with minimal departure from intakes reported for the NHANES 2001-02. We examined the effect of the number of servings/d of Food Pyramid groups set at 1992 and at 2005 FGP recommendations for 1600, 2200, and 2800 kcal (1 kcal = 4.184 kJ) levels. We calculated energy and nutrients provided by different FGP dietary patterns. Within current U.S. dietary practices, following the 1992 FGP without sodium restriction may provide 200 more kcal than recommended for each energy level. Although it can meet most of old nutrient recommendations (1989), it fails to meet the latest dietary reference intakes, especially for the 1600 kcal level. The 2005 FGP appears to provide less energy and more adequate nutrient intakes, with the exception of vitamin E and potassium for some groups. However, without discretionary energy restriction, Americans are at risk of having excessive energy intake even if they follow the 2005 FGP food serving recommendations. Our analysis suggests that following the 2005 FGP may be associated with lower energy and optimal nutrient intake. Careful restriction of discretionary calories appears necessary for appropriate energy intakes to be maintained. PMID:16614427

  19. The 2005 USDA Food Guide Pyramid is associated with more adequate nutrient intakes within energy constraints than the 1992 Pyramid.

    PubMed

    Gao, Xiang; Wilde, Parke E; Lichtenstein, Alice H; Tucker, Katherine L

    2006-05-01

    The USDA issued the Food Guide Pyramid (FGP) to help Americans choose healthy diets. We examined whether adherence to the 1992 and 2005 FGP was associated with moderate energy and adequate nutrient intakes. We used data for 2138 men and 2213 women > 18 y old, from the 2001-2002 U.S. National Health and Nutrition Examination Survey (NHANES). Quadratic programming was used to generate diets with minimal departure from intakes reported for the NHANES 2001-02. We examined the effect of the number of servings/d of Food Pyramid groups set at 1992 and at 2005 FGP recommendations for 1600, 2200, and 2800 kcal (1 kcal = 4.184 kJ) levels. We calculated energy and nutrients provided by different FGP dietary patterns. Within current U.S. dietary practices, following the 1992 FGP without sodium restriction may provide 200 more kcal than recommended for each energy level. Although it can meet most of old nutrient recommendations (1989), it fails to meet the latest dietary reference intakes, especially for the 1600 kcal level. The 2005 FGP appears to provide less energy and more adequate nutrient intakes, with the exception of vitamin E and potassium for some groups. However, without discretionary energy restriction, Americans are at risk of having excessive energy intake even if they follow the 2005 FGP food serving recommendations. Our analysis suggests that following the 2005 FGP may be associated with lower energy and optimal nutrient intake. Careful restriction of discretionary calories appears necessary for appropriate energy intakes to be maintained.

  20. Additive genetic variation in resistance traits of an exotic pine species: little evidence for constraints on evolution of resistance against native herbivores

    PubMed Central

    Moreira, X; Zas, R; Sampedro, L

    2013-01-01

    The apparent failure of invasions by alien pines in Europe has been explained by the co-occurrence of native pine congeners supporting herbivores that might easily recognize the new plants as hosts. Previous studies have reported that exotic pines show reduced tolerance and capacity to induce resistance to those native herbivores. We hypothesize that limited genetic variation in resistance to native herbivores and the existence of evolutionary trade-offs between growth and resistance could represent additional potential constraints on the evolution of invasiveness of exotic pines outside their natural range. In this paper, we examined genetic variation for constitutive and induced chemical defences (measured as non-volatile resin in the stem and total phenolics in the needles) and resistance to two major native generalist herbivores of pines in cafeteria bioassays (the phloem-feeder Hylobius abietis and the defoliator Thaumetopoea pityocampa) using half-sib families drawn from a sample of the population of Pinus radiata introduced to Spain in the mid-19th century. We found (i) significant genetic variation, with moderate-to-high narrow-sense heritabilities for both the production of constitutive non-volatile resin and induced total phenolics, and for constitutive resistance against T. pityocampa in bioassays, (ii) no evolutionary trade-offs between plant resistance and growth traits or between the production of different quantitative chemical defences and (iii) a positive genetic correlation between constitutive resistance to the two studied herbivores. Overall, results of our study indicate that the exotic pine P. radiata has limited genetic constraints on the evolution of resistance against herbivores in its introduced range, suggesting that, at least in terms of interactions with these enemies, this pine species has potential to become invasive in the future. PMID:23232833

  1. Image-guided intensity-modulated radiotherapy for prostate cancer: Dose constraints for the anterior rectal wall to minimize rectal toxicity

    SciTech Connect

    Peterson, Jennifer L.; Buskirk, Steven J.; Heckman, Michael G.; Diehl, Nancy N.; Bernard, Johnny R.; Tzou, Katherine S.; Casale, Henry E.; Bellefontaine, Louis P.; Serago, Christopher; Kim, Siyong; Vallow, Laura A.; Daugherty, Larry C.; Ko, Stephen J.

    2014-04-01

    Rectal adverse events (AEs) are a major concern with definitive radiotherapy (RT) treatment for prostate cancer. The anterior rectal wall is at the greatest risk of injury as it lies closest to the target volume and receives the highest dose of RT. This study evaluated the absolute volume of anterior rectal wall receiving a high dose to identify potential ideal dose constraints that can minimize rectal AEs. A total of 111 consecutive patients with Stage T1c to T3a N0 M0 prostate cancer who underwent image-guided intensity-modulated RT at our institution were included. AEs were graded according to the Common Terminology Criteria for Adverse Events, version 4.0. The volume of anterior rectal wall receiving 5 to 80 Gy in 2.5-Gy increments was determined. Multivariable Cox regression models were used to identify cut points in these volumes that led to an increased risk of early and late rectal AEs. Early AEs occurred in most patients (88%); however, relatively few of them (13%) were grade ≥2. At 5 years, the cumulative incidence of late rectal AEs was 37%, with only 5% being grade ≥2. For almost all RT doses, we identified a threshold of irradiated absolute volume of anterior rectal wall above which there was at least a trend toward a significantly higher rate of AEs. Most strikingly, patients with more than 1.29, 0.73, or 0.45 cm{sup 3} of anterior rectal wall exposed to radiation doses of 67.5, 70, or 72.5 Gy, respectively, had a significantly increased risk of late AEs (relative risks [RR]: 2.18 to 2.72; p ≤ 0.041) and of grade ≥ 2 early AEs (RR: 6.36 to 6.48; p = 0.004). Our study provides evidence that definitive image-guided intensity-modulated radiotherapy (IG-IMRT) for prostate cancer is well tolerated and also identifies dose thresholds for the absolute volume of anterior rectal wall above which patients are at greater risk of early and late complications.

  2. AudioGene: predicting hearing loss genotypes from phenotypes to guide genetic screening.

    PubMed

    Taylor, Kyle R; Deluca, Adam P; Shearer, A Eliot; Hildebrand, Michael S; Black-Ziegelbein, E Ann; Anand, V Nikhil; Sloan, Christina M; Eppsteiner, Robert W; Scheetz, Todd E; Huygen, Patrick L M; Smith, Richard J H; Braun, Terry A; Casavant, Thomas L

    2013-04-01

    Autosomal dominant nonsyndromic hearing loss (ADNSHL) is a common and often progressive sensory deficit. ADNSHL displays a high degree of genetic heterogeneity and varying rates of progression. Accurate, comprehensive, and cost-effective genetic testing facilitates genetic counseling and provides valuable prognostic information to affected individuals. In this article, we describe the algorithm underlying AudioGene, a software system employing machine-learning techniques that utilizes phenotypic information derived from audiograms to predict the genetic cause of hearing loss in persons segregating ADNSHL. Our data show that AudioGene has an accuracy of 68% in predicting the causative gene within its top three predictions, as compared with 44% for a majority classifier. We also show that AudioGene remains effective for audiograms with high levels of clinical measurement noise. We identify audiometric outliers for each genetic locus and hypothesize that outliers may reflect modifying genetic effects. As personalized genomic medicine becomes more common, AudioGene will be increasingly useful as a phenotypic filter to assess pathogenicity of variants identified by massively parallel sequencing. PMID:23280582

  3. Simulation of Finnish Population History, Guided by Empirical Genetic Data, to Assess Power of Rare-Variant Tests in Finland

    PubMed Central

    Wang, Sophie R.; Agarwala, Vineeta; Flannick, Jason; Chiang, Charleston W.K.; Altshuler, David; Flannick, Jason; Manning, Alisa; Hartl, Christopher; Agarwala, Vineeta; Fontanillas, Pierre; Green, Todd; Banks, Eric; DePristo, Mark; Poplin, Ryan; Shakir, Khalid; Fennell, Timothy; Murphy, Jacquelyn; Burtt, Noël; Gabriel, Stacey; Altshuler, David; Fuchsberger, Christian; Kang, Hyun Min; Sim, Xueling; Ma, Clement; Locke, Adam; Blackwell, Thomas; Jackson, Anne; Teslovich, Tanya; Stringham, Heather; Chines, Peter; Kwan, Phoenix; Huyghe, Jeroen; Tan, Adrian; Jun, Goo; Stitzel, Michael; Bergman, Richard N.; Bonnycastle, Lori; Tuomilehto, Jaakko; Collins, Francis S.; Scott, Laura; Mohlke, Karen; Abecasis, Gonçalo; Boehnke, Michael; Strom, Tim; Gieger, Christian; Müller-Nurasyid, Martina; Grallert, Harald; Kriebel, Jennifer; Ried, Janina; Hrabé de Angelis, Martin; Huth, Cornelia; Meisinger, Christa; Peters, Annette; Rathmann, Wolfgang; Strauch, Konstantin; Meitinger, Thomas; Kravic, Jasmina; Ladenvall, Claes; Toumi, Tiinamaija; Isomaa, Bo; Groop, Leif; Gaulton, Kyle; Moutsianas, Loukas; Rivas, Manny; Pearson, Richard; Mahajan, Anubha; Prokopenko, Inga; Kumar, Ashish; Perry, John; Chen, Jeff; Howie, Bryan; van de Bunt, Martijn; Small, Kerrin; Lindgren, Cecilia; Lunter, Gerton; Robertson, Neil; Rayner, Will; Morris, Andrew; Buck, David; Hattersley, Andrew; Spector, Tim; McVean, Gil; Frayling, Tim; Donnelly, Peter; McCarthy, Mark; Hirschhorn, Joel N.

    2014-01-01

    Finnish samples have been extensively utilized in studying single-gene disorders, where the founder effect has clearly aided in discovery, and more recently in genome-wide association studies of complex traits, where the founder effect has had less obvious impacts. As the field starts to explore rare variants’ contribution to polygenic traits, it is of great importance to characterize and confirm the Finnish founder effect in sequencing data and to assess its implications for rare-variant association studies. Here, we employ forward simulation, guided by empirical deep resequencing data, to model the genetic architecture of quantitative polygenic traits in both the general European and the Finnish populations simultaneously. We demonstrate that power of rare-variant association tests is higher in the Finnish population, especially when variants’ phenotypic effects are tightly coupled with fitness effects and therefore reflect a greater contribution of rarer variants. SKAT-O, variable-threshold tests, and single-variant tests are more powerful than other rare-variant methods in the Finnish population across a range of genetic models. We also compare the relative power and efficiency of exome array genotyping to those of high-coverage exome sequencing. At a fixed cost, less expensive genotyping strategies have far greater power than sequencing; in a fixed number of samples, however, genotyping arrays miss a substantial portion of genetic signals detected in sequencing, even in the Finnish founder population. As genetic studies probe sequence variation at greater depth in more diverse populations, our simulation approach provides a framework for evaluating various study designs for gene discovery. PMID:24768551

  4. Hippocampal transcriptome-guided genetic analysis of correlated episodic memory phenotypes in Alzheimer's disease

    PubMed Central

    Yan, Jingwen; Kim, Sungeun; Nho, Kwangsik; Chen, Rui; Risacher, Shannon L.; Moore, Jason H.; Saykin, Andrew J.; Shen, Li

    2015-01-01

    As the most common type of dementia, Alzheimer's disease (AD) is a neurodegenerative disorder initially manifested by impaired memory performances. While the diagnosis information indicates a dichotomous status of a patient, memory scores have the potential to capture the continuous nature of the disease progression and may provide more insights into the underlying mechanism. In this work, we performed a targeted genetic study of memory scores on an AD cohort to identify the associations between a set of genes highly expressed in the hippocampal region and seven cognitive scores related to episodic memory. Both main effects and interaction effects of the targeted genetic markers on these correlated memory scores were examined. In addition to well-known AD genetic markers APOE and TOMM40, our analysis identified a new risk gene NAV2 through the gene-level main effect analysis. NAV2 was found to be significantly and consistently associated with all seven episodic memory scores. Genetic interaction analysis also yielded a few promising hits warranting further investigation, especially for the RAVLT list B Score. PMID:25859259

  5. Genetics

    MedlinePlus

    ... Inheritance; Heterozygous; Inheritance patterns; Heredity and disease; Heritable; Genetic markers ... The chromosomes are made up of strands of genetic information called DNA. Each chromosome contains sections of ...

  6. A new approach to self-organizing fuzzy polynomial neural networks guided by genetic optimization

    NASA Astrophysics Data System (ADS)

    Oh, Sung-Kwun; Pedrycz, Witold

    2005-09-01

    In this study, we introduce a new topology of Fuzzy Polynomial Neural Networks (FPNN) that is based on a genetically optimized multilayer perceptron with fuzzy polynomial neurons (FPNs) and discuss its comprehensive design methodology. The underlying methodology involves mechanisms of genetic optimization, especially genetic algorithms (GAs). Let us recall that the design of the “conventional” FPNNs uses an extended Group Method of Data Handling (GMDH) and exploits a fixed fuzzy inference type located at each FPN of the FPNN as well as considers a fixed number of input nodes at FPNs (or nodes) located in each layer. The proposed FPNN gives rise to a structurally optimized structure and comes with a substantial level of flexibility in comparison to the one we encounter in conventional FPNNs. The structural optimization is realized via GAs whereas in the case of the parametric optimization we proceed with a standard least square method based learning. Through the consecutive process of such structural and parametric optimization, an optimized and flexible fuzzy neural network is generated in a dynamic fashion. The performance of the proposed gFPNN is quantified through experimentation that exploits standard data already being used in fuzzy modeling. The results reveal superiority of the proposed networks over the existing fuzzy and neural models.

  7. Geomorphic and Fish Genetics Constraints on Late Cenozoic Long Wavelength Topographic Evolution of the Hangay Mountains, Central Mongolia

    NASA Astrophysics Data System (ADS)

    Wegmann, K. W.; Tamra, M.; Sabaj Pérez, M.; Lopresti, M.; Cole, M. B.; Gosse, J. C.; Smith, S. G.; Bayasgalan, G.; Ancuta, L. D.; McDannell, K. T.; Gallen, S. F.

    2014-12-01

    The Hangay Mountains stand 1.5 - 2 km above adjacent lowlands and the timing and cause of their high elevation is debated. As part of a broad collaborative project, we synthesize several data sets that collectively suggest the Hangay increased in elevation during the mid-to-late Miocene, while topographic relief, one metric commonly associated with active mountain ranges, remained largely unchanged. The topographic crest of the Hangay forms the drainage divide between the Selenga River and internal drainage of the Mongolian Depression of Lakes (MDL) and northern Gobi. Synthetic drainage divides for the Hangay were created by filtering digital topography in the spectral domain (50 - 200 km wavelengths) using a 2D-FFT function. The co-location of the synthetic and modern divides suggests that the Hangay divide is in a stable, equilibrium configuration. This assumption is corroborated by chi-maps of steady-state river channel elevations that exhibit nearly equal values across water divides. An exception to both of these metrics occurs in the northwest Hangay where the Bulnay fault crosses a low divide between the western Selenga basin and the MDL. Recent basalt vesicle paleoaltimetry results allow for ~1 km of surface uplift of the central Hangay in the past ~ 10 Ma. These same basalt flows in-filled late Miocene valleys cut into basement with a minimum of 800 m of local relief; similar to the amount of modern, post-glacial relief along the drainage divide. mtDNA analyses from > 250 combined Stone Loaches (Barbatula), Grayling (Thymallus), and Eurasian Dace (Leuciscus) samples from both sides of the continental drainage divide are supportive of Miocene surface uplift. Molecular genetic differences between the loach populations across the divide suggest that they separated from a common ancestor between 20 and 11 Ma. This date is consistent with the timing of surface uplift and valley incision preserved in the Miocene basalt flows. The dace and grayling populations on

  8. Genetically distinct pathways guide effector export through the type VI secretion system

    PubMed Central

    Whitney, John C.; Beck, Christina M.; Goo, Young Ah; Russell, Alistair B.; Harding, Brittany; De Leon, Justin A.; Cunningham, David A.; Tran, Bao Q.; Low, David A.; Goodlett, David R.; Hayes, Christopher S.; Mougous, Joseph D.

    2014-01-01

    Summary Bacterial secretion systems often employ molecular chaperones to recognize and facilitate export of their substrates. Recent work demonstrated that a secreted component of the type VI secretion system (T6SS), hemolysin co-regulated protein (Hcp), binds directly to effectors, enhancing their stability in the bacterial cytoplasm. Herein, we describe a quantitative cellular proteomics screen for T6S substrates that exploits this chaperone-like quality of Hcp. Application of this approach to the Hcp secretion island I-encoded T6SS (H1-T6SS) of Pseudomonas aeruginosa led to the identification of a novel effector protein, termed Tse4 (type VI secretion exported 4), subsequently shown to act as a potent intra-specific H1-T6SS-delivered antibacterial toxin. Interestingly, our screen failed to identify two predicted H1-T6SS effectors, Tse5 and Tse6, which differ from Hcp-stabilized substrates by the presence of toxin-associated PAAR-repeat motifs and genetic linkage to members of the valine-glycine repeat protein G (vgrG) genes. Genetic studies further distinguished these two groups of effectors: Hcp-stabilized effectors were found to display redundancy in interbacterial competition with respect to the requirement for the two H1-T6SS-exported VgrG proteins, whereas Tse5 and Tse6 delivery strictly required a cognate VgrG. Together, we propose that interaction with either VgrG or Hcp defines distinct pathways for T6S effector export. PMID:24589350

  9. Human genetics in rheumatoid arthritis guides a high-throughput drug screen of the CD40 signaling pathway.

    PubMed

    Li, Gang; Diogo, Dorothée; Wu, Di; Spoonamore, Jim; Dancik, Vlado; Franke, Lude; Kurreeman, Fina; Rossin, Elizabeth J; Duclos, Grant; Hartland, Cathy; Zhou, Xuezhong; Li, Kejie; Liu, Jun; De Jager, Philip L; Siminovitch, Katherine A; Zhernakova, Alexandra; Raychaudhuri, Soumya; Bowes, John; Eyre, Steve; Padyukov, Leonid; Gregersen, Peter K; Worthington, Jane; Gupta, Namrata; Clemons, Paul A; Stahl, Eli; Tolliday, Nicola; Plenge, Robert M

    2013-05-01

    Although genetic and non-genetic studies in mouse and human implicate the CD40 pathway in rheumatoid arthritis (RA), there are no approved drugs that inhibit CD40 signaling for clinical care in RA or any other disease. Here, we sought to understand the biological consequences of a CD40 risk variant in RA discovered by a previous genome-wide association study (GWAS) and to perform a high-throughput drug screen for modulators of CD40 signaling based on human genetic findings. First, we fine-map the CD40 risk locus in 7,222 seropositive RA patients and 15,870 controls, together with deep sequencing of CD40 coding exons in 500 RA cases and 650 controls, to identify a single SNP that explains the entire signal of association (rs4810485, P = 1.4×10(-9)). Second, we demonstrate that subjects homozygous for the RA risk allele have ∼33% more CD40 on the surface of primary human CD19+ B lymphocytes than subjects homozygous for the non-risk allele (P = 10(-9)), a finding corroborated by expression quantitative trait loci (eQTL) analysis in peripheral blood mononuclear cells from 1,469 healthy control individuals. Third, we use retroviral shRNA infection to perturb the amount of CD40 on the surface of a human B lymphocyte cell line (BL2) and observe a direct correlation between amount of CD40 protein and phosphorylation of RelA (p65), a subunit of the NF-κB transcription factor. Finally, we develop a high-throughput NF-κB luciferase reporter assay in BL2 cells activated with trimerized CD40 ligand (tCD40L) and conduct an HTS of 1,982 chemical compounds and FDA-approved drugs. After a series of counter-screens and testing in primary human CD19+ B cells, we identify 2 novel chemical inhibitors not previously implicated in inflammation or CD40-mediated NF-κB signaling. Our study demonstrates proof-of-concept that human genetics can be used to guide the development of phenotype-based, high-throughput small-molecule screens to identify potential novel therapies in

  10. Human Genetics in Rheumatoid Arthritis Guides a High-Throughput Drug Screen of the CD40 Signaling Pathway

    PubMed Central

    Li, Gang; Diogo, Dorothée; Wu, Di; Spoonamore, Jim; Dancik, Vlado; Franke, Lude; Kurreeman, Fina; Rossin, Elizabeth J.; Duclos, Grant; Hartland, Cathy; Zhou, Xuezhong; Li, Kejie; Liu, Jun; De Jager, Philip L.; Siminovitch, Katherine A.; Zhernakova, Alexandra; Raychaudhuri, Soumya; Bowes, John; Eyre, Steve; Padyukov, Leonid; Gregersen, Peter K.; Worthington, Jane; Gupta, Namrata; Clemons, Paul A.; Stahl, Eli; Tolliday, Nicola; Plenge, Robert M.

    2013-01-01

    Although genetic and non-genetic studies in mouse and human implicate the CD40 pathway in rheumatoid arthritis (RA), there are no approved drugs that inhibit CD40 signaling for clinical care in RA or any other disease. Here, we sought to understand the biological consequences of a CD40 risk variant in RA discovered by a previous genome-wide association study (GWAS) and to perform a high-throughput drug screen for modulators of CD40 signaling based on human genetic findings. First, we fine-map the CD40 risk locus in 7,222 seropositive RA patients and 15,870 controls, together with deep sequencing of CD40 coding exons in 500 RA cases and 650 controls, to identify a single SNP that explains the entire signal of association (rs4810485, P = 1.4×10−9). Second, we demonstrate that subjects homozygous for the RA risk allele have ∼33% more CD40 on the surface of primary human CD19+ B lymphocytes than subjects homozygous for the non-risk allele (P = 10−9), a finding corroborated by expression quantitative trait loci (eQTL) analysis in peripheral blood mononuclear cells from 1,469 healthy control individuals. Third, we use retroviral shRNA infection to perturb the amount of CD40 on the surface of a human B lymphocyte cell line (BL2) and observe a direct correlation between amount of CD40 protein and phosphorylation of RelA (p65), a subunit of the NF-κB transcription factor. Finally, we develop a high-throughput NF-κB luciferase reporter assay in BL2 cells activated with trimerized CD40 ligand (tCD40L) and conduct an HTS of 1,982 chemical compounds and FDA–approved drugs. After a series of counter-screens and testing in primary human CD19+ B cells, we identify 2 novel chemical inhibitors not previously implicated in inflammation or CD40-mediated NF-κB signaling. Our study demonstrates proof-of-concept that human genetics can be used to guide the development of phenotype-based, high-throughput small-molecule screens to identify potential novel therapies in

  11. Breeding and Genetics Symposium: networks and pathways to guide genomic selection.

    PubMed

    Snelling, W M; Cushman, R A; Keele, J W; Maltecca, C; Thomas, M G; Fortes, M R S; Reverter, A

    2013-02-01

    Many traits affecting profitability and sustainability of meat, milk, and fiber production are polygenic, with no single gene having an overwhelming influence on observed variation. No knowledge of the specific genes controlling these traits has been needed to make substantial improvement through selection. Significant gains have been made through phenotypic selection enhanced by pedigree relationships and continually improving statistical methodology. Genomic selection, recently enabled by assays for dense SNP located throughout the genome, promises to increase selection accuracy and accelerate genetic improvement by emphasizing the SNP most strongly correlated to phenotype although the genes and sequence variants affecting phenotype remain largely unknown. These genomic predictions theoretically rely on linkage disequilibrium (LD) between genotyped SNP and unknown functional variants, but familial linkage may increase effectiveness when predicting individuals related to those in the training data. Genomic selection with functional SNP genotypes should be less reliant on LD patterns shared by training and target populations, possibly allowing robust prediction across unrelated populations. Although the specific variants causing polygenic variation may never be known with certainty, a number of tools and resources can be used to identify those most likely to affect phenotype. Associations of dense SNP genotypes with phenotype provide a 1-dimensional approach for identifying genes affecting specific traits; in contrast, associations with multiple traits allow defining networks of genes interacting to affect correlated traits. Such networks are especially compelling when corroborated by existing functional annotation and established molecular pathways. The SNP occurring within network genes, obtained from public databases or derived from genome and transcriptome sequences, may be classified according to expected effects on gene products. As illustrated by

  12. Molecular protein adaptor with genetically encoded interaction sites guiding the hierarchical assembly of plasmonically active nanoparticle architectures.

    PubMed

    Schreiber, Andreas; Huber, Matthias C; Cölfen, Helmut; Schiller, Stefan M

    2015-01-01

    The control over the defined assembly of nano-objects with nm-precision is important to create systems and materials with enhanced properties, for example, metamaterials. In nature, the precise assembly of inorganic nano-objects with unique features, for example, magnetosomes, is accomplished by efficient and reliable recognition schemes involving protein effectors. Here we present a molecular approach using protein-based 'adaptors/connectors' with genetically encoded interaction sites to guide the assembly and functionality of different plasmonically active gold nanoparticle architectures (AuNP). The interaction of the defined geometricaly shaped protein adaptors with the AuNP induces the self-assembly of nanoarchitectures ranging from AuNP encapsulation to one-dimensional chain-like structures, complex networks and stars. Synthetic biology and bionanotechnology are applied to co-translationally encode unnatural amino acids as additional site-specific modification sites to generate functionalized biohybrid nanoarchitectures. This protein adaptor-based nano-object assembly approach might be expanded to other inorganic nano-objects creating biohybrid materials with unique electronic, photonic, plasmonic and magnetic properties. PMID:25813537

  13. Genome-wide recessive genetic screening in mammalian cells with a lentiviral CRISPR-guide RNA library.

    PubMed

    Koike-Yusa, Hiroko; Li, Yilong; Tan, E-Pien; Velasco-Herrera, Martin Del Castillo; Yusa, Kosuke

    2014-03-01

    Identification of genes influencing a phenotype of interest is frequently achieved through genetic screening by RNA interference (RNAi) or knockouts. However, RNAi may only achieve partial depletion of gene activity, and knockout-based screens are difficult in diploid mammalian cells. Here we took advantage of the efficiency and high throughput of genome editing based on type II, clustered, regularly interspaced, short palindromic repeats (CRISPR)-CRISPR-associated (Cas) systems to introduce genome-wide targeted mutations in mouse embryonic stem cells (ESCs). We designed 87,897 guide RNAs (gRNAs) targeting 19,150 mouse protein-coding genes and used a lentiviral vector to express these gRNAs in ESCs that constitutively express Cas9. Screening the resulting ESC mutant libraries for resistance to either Clostridium septicum alpha-toxin or 6-thioguanine identified 27 known and 4 previously unknown genes implicated in these phenotypes. Our results demonstrate the potential for efficient loss-of-function screening using the CRISPR-Cas9 system.

  14. Molecular protein adaptor with genetically encoded interaction sites guiding the hierarchical assembly of plasmonically active nanoparticle architectures

    NASA Astrophysics Data System (ADS)

    Schreiber, Andreas; Huber, Matthias C.; Cölfen, Helmut; Schiller, Stefan M.

    2015-03-01

    The control over the defined assembly of nano-objects with nm-precision is important to create systems and materials with enhanced properties, for example, metamaterials. In nature, the precise assembly of inorganic nano-objects with unique features, for example, magnetosomes, is accomplished by efficient and reliable recognition schemes involving protein effectors. Here we present a molecular approach using protein-based ‘adaptors/connectors’ with genetically encoded interaction sites to guide the assembly and functionality of different plasmonically active gold nanoparticle architectures (AuNP). The interaction of the defined geometricaly shaped protein adaptors with the AuNP induces the self-assembly of nanoarchitectures ranging from AuNP encapsulation to one-dimensional chain-like structures, complex networks and stars. Synthetic biology and bionanotechnology are applied to co-translationally encode unnatural amino acids as additional site-specific modification sites to generate functionalized biohybrid nanoarchitectures. This protein adaptor-based nano-object assembly approach might be expanded to other inorganic nano-objects creating biohybrid materials with unique electronic, photonic, plasmonic and magnetic properties.

  15. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Capsicum represents one of several well characterized Solanaceous genera. A wealth of classical and molecular genetics research is available for the genus. Information gleaned from its cultivated relatives, tomato and potato, provide further insight for basic and applied studies. Early ...

  16. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintaining genetic variation in wild populations of Arctic organisms is fundamental to the long-term persistence of high latitude biodiversity. Variability is important because it provides options for species to respond to changing environmental conditions and novel challenges such as emerging path...

  17. A Microsatellite Guided Insight into the Genetic Status of Adi, an Isolated Hunting-Gathering Tribe of Northeast India

    PubMed Central

    Krithika, S.; Maji, Suvendu; Vasulu, T. S.

    2008-01-01

    Tibeto-Burman populations of India provide an insight into the peopling of India and aid in understanding their genetic relationship with populations of East, South and Southeast Asia. The study investigates the genetic status of one such Tibeto-Burman group, Adi of Arunachal Pradesh based on 15 autosomal microsatellite markers. Further the study examines, based on 9 common microsatellite loci, the genetic relationship of Adi with 16 other Tibeto-Burman speakers of India and 28 neighboring populations of East and Southeast Asia. Overall, the results support the recent formation of the Adi sub-tribes from a putative ancestral group and reveal that geographic contiguity is a major influencing factor of the genetic affinity among the Tibeto-Burman populations of India. PMID:18596928

  18. A microsatellite guided insight into the genetic status of adi, an isolated hunting-gathering tribe of northeast India.

    PubMed

    Krithika, S; Maji, Suvendu; Vasulu, T S

    2008-01-01

    Tibeto-Burman populations of India provide an insight into the peopling of India and aid in understanding their genetic relationship with populations of East, South and Southeast Asia. The study investigates the genetic status of one such Tibeto-Burman group, Adi of Arunachal Pradesh based on 15 autosomal microsatellite markers. Further the study examines, based on 9 common microsatellite loci, the genetic relationship of Adi with 16 other Tibeto-Burman speakers of India and 28 neighboring populations of East and Southeast Asia. Overall, the results support the recent formation of the Adi sub-tribes from a putative ancestral group and reveal that geographic contiguity is a major influencing factor of the genetic affinity among the Tibeto-Burman populations of India.

  19. Web-based software tool for constraint-based design specification of synthetic biological systems.

    PubMed

    Oberortner, Ernst; Densmore, Douglas

    2015-06-19

    miniEugene provides computational support for solving combinatorial design problems, enabling users to specify and enumerate designs for novel biological systems based on sets of biological constraints. This technical note presents a brief tutorial for biologists and software engineers in the field of synthetic biology on how to use miniEugene. After reading this technical note, users should know which biological constraints are available in miniEugene, understand the syntax and semantics of these constraints, and be able to follow a step-by-step guide to specify the design of a classical synthetic biological system-the genetic toggle switch.1 We also provide links and references to more information on the miniEugene web application and the integration of the miniEugene software library into sophisticated Computer-Aided Design (CAD) tools for synthetic biology ( www.eugenecad.org ).

  20. Web-based software tool for constraint-based design specification of synthetic biological systems.

    PubMed

    Oberortner, Ernst; Densmore, Douglas

    2015-06-19

    miniEugene provides computational support for solving combinatorial design problems, enabling users to specify and enumerate designs for novel biological systems based on sets of biological constraints. This technical note presents a brief tutorial for biologists and software engineers in the field of synthetic biology on how to use miniEugene. After reading this technical note, users should know which biological constraints are available in miniEugene, understand the syntax and semantics of these constraints, and be able to follow a step-by-step guide to specify the design of a classical synthetic biological system-the genetic toggle switch.1 We also provide links and references to more information on the miniEugene web application and the integration of the miniEugene software library into sophisticated Computer-Aided Design (CAD) tools for synthetic biology ( www.eugenecad.org ). PMID:25426642

  1. Method for Optimal Sensor Deployment on 3D Terrains Utilizing a Steady State Genetic Algorithm with a Guided Walk Mutation Operator Based on the Wavelet Transform

    PubMed Central

    Unaldi, Numan; Temel, Samil; Asari, Vijayan K.

    2012-01-01

    One of the most critical issues of Wireless Sensor Networks (WSNs) is the deployment of a limited number of sensors in order to achieve maximum coverage on a terrain. The optimal sensor deployment which enables one to minimize the consumed energy, communication time and manpower for the maintenance of the network has attracted interest with the increased number of studies conducted on the subject in the last decade. Most of the studies in the literature today are proposed for two dimensional (2D) surfaces; however, real world sensor deployments often arise on three dimensional (3D) environments. In this paper, a guided wavelet transform (WT) based deployment strategy (WTDS) for 3D terrains, in which the sensor movements are carried out within the mutation phase of the genetic algorithms (GAs) is proposed. The proposed algorithm aims to maximize the Quality of Coverage (QoC) of a WSN via deploying a limited number of sensors on a 3D surface by utilizing a probabilistic sensing model and the Bresenham's line of sight (LOS) algorithm. In addition, the method followed in this paper is novel to the literature and the performance of the proposed algorithm is compared with the Delaunay Triangulation (DT) method as well as a standard genetic algorithm based method and the results reveal that the proposed method is a more powerful and more successful method for sensor deployment on 3D terrains. PMID:22666078

  2. New knowledge-based genetic algorithm for excavator boom structural optimization

    NASA Astrophysics Data System (ADS)

    Hua, Haiyan; Lin, Shuwen

    2014-03-01

    Due to the insufficiency of utilizing knowledge to guide the complex optimal searching, existing genetic algorithms fail to effectively solve excavator boom structural optimization problem. To improve the optimization efficiency and quality, a new knowledge-based real-coded genetic algorithm is proposed. A dual evolution mechanism combining knowledge evolution with genetic algorithm is established to extract, handle and utilize the shallow and deep implicit constraint knowledge to guide the optimal searching of genetic algorithm circularly. Based on this dual evolution mechanism, knowledge evolution and population evolution can be connected by knowledge influence operators to improve the configurability of knowledge and genetic operators. Then, the new knowledge-based selection operator, crossover operator and mutation operator are proposed to integrate the optimal process knowledge and domain culture to guide the excavator boom structural optimization. Eight kinds of testing algorithms, which include different genetic operators, are taken as examples to solve the structural optimization of a medium-sized excavator boom. By comparing the results of optimization, it is shown that the algorithm including all the new knowledge-based genetic operators can more remarkably improve the evolutionary rate and searching ability than other testing algorithms, which demonstrates the effectiveness of knowledge for guiding optimal searching. The proposed knowledge-based genetic algorithm by combining multi-level knowledge evolution with numerical optimization provides a new effective method for solving the complex engineering optimization problem.

  3. Evolutionary Constraints to Viroid Evolution

    PubMed Central

    Elena, Santiago F.; Gómez, Gustavo; Daròs, José-Antonio

    2009-01-01

    We suggest that viroids are trapped into adaptive peaks as the result of adaptive constraints. The first one is imposed by the necessity to fold into packed structures to escape from RNA silencing. This creates antagonistic epistases, which make future adaptive trajectories contingent upon the first mutation and slow down the rate of adaptation. This second constraint can only be surpassed by increasing genetic redundancy or by recombination. Eigen’s paradox imposes a limit to the increase in genome complexity in the absence of mechanisms reducing mutation rate. Therefore, recombination appears as the only possible route to evolutionary innovation in viroids. PMID:21994548

  4. Hydroeconomic optimization of reservoir management under downstream water quality constraints

    NASA Astrophysics Data System (ADS)

    Davidsen, Claus; Liu, Suxia; Mo, Xingguo; Holm, Peter E.; Trapp, Stefan; Rosbjerg, Dan; Bauer-Gottwein, Peter

    2015-10-01

    A hydroeconomic optimization approach is used to guide water management in a Chinese river basin with the objectives of meeting water quantity and water quality constraints, in line with the China 2011 No. 1 Policy Document and 2015 Ten-point Water Plan. The proposed modeling framework couples water quantity and water quality management and minimizes the total costs over a planning period assuming stochastic future runoff. The outcome includes cost-optimal reservoir releases, groundwater pumping, water allocation, wastewater treatments and water curtailments. The optimization model uses a variant of stochastic dynamic programming known as the water value method. Nonlinearity arising from the water quality constraints is handled with an effective hybrid method combining genetic algorithms and linear programming. Untreated pollutant loads are represented by biochemical oxygen demand (BOD), and the resulting minimum dissolved oxygen (DO) concentration is computed with the Streeter-Phelps equation and constrained to match Chinese water quality targets. The baseline water scarcity and operational costs are estimated to 15.6 billion CNY/year. Compliance to water quality grade III causes a relatively low increase to 16.4 billion CNY/year. Dilution plays an important role and increases the share of surface water allocations to users situated furthest downstream in the system. The modeling framework generates decision rules that result in the economically efficient strategy for complying with both water quantity and water quality constraints.

  5. Genetics Home Reference: adermatoglyphia

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions adermatoglyphia adermatoglyphia Enable Javascript to ...

  6. Berthierine and chamosite hydrothermal: genetic guides in the Peña Colorada magnetite-bearing ore deposit, Mexico

    NASA Astrophysics Data System (ADS)

    Rivas-Sanchez, M. L.; Alva-Valdivia, L. M.; Arenas-Alatorre, J.; Urrutia-Fucugauchi, J.; Ruiz-Sandoval, M.; Ramos-Molina, M. A.

    2006-10-01

    We report the first finding of berthierine and chamosite in Mexico. They occur in the iron-ore deposit of Peña Colorada, Colima. Their genetic characteristics show two different mineralization events associated mainly to the magnetite ore. Berthierine is an Fe-rich and Mg-low 1:1 layer phyllosilicate of hydrothermal sedimentary origin. Its structure is 7 Å, d hkl [10 0] basal spacing and low degree structural ordering. The phyllosilicate has been identified by a lack of 14 Å basal reflection on X-ray diffraction (XRD) patterns. These data were supported by High Resolution Transmision Electron Microscopy (HRTEM) images that show thick packets of berthierine in well defined parallel plates. From the analysis of Fast Fourier Transform (FFT), we found around [1 0 0] reflections of berhierine 7.12 Å and corresponding angles of hexagonal crystalline structure. Berthierine has a microcrystalline structure, dark green color, and high refraction index (1.64 to 1.65). Birefringence is low, near 0.007 to null and it is associated to nanoparticles (<15 nm) and microparticles of magnetite (<25 μm), fine grain siderite, and organic matter. Its texture is intergranular-interstratified with colloform banding. The chamosite Mg-rich is of hydrothermal epigenetic origin affected by low-degree metamorphism. It is an Fe-rich 2:1 layer silicate, with basal space of 14 Å, d hkl [0 0 1]. The chamosite occurs as lamellar in sizes ranging from 50 to 150 μm. It has intense green color and refraction index from 1.64 to 1.65. The birefringence is near 0.008, with biaxial (-) orientation and a 2V small. It is associated mainly to sericite, epidote, clay, feldspar, and magnetite. Chamosite is emplaced in open spaces filling and linings. Mössbauer spectra of berthierine and chamosite are similar. They show the typical spectra of paramagnetic substances, with two well defined unfoldings corresponding to the oxidation state of Fe+2 and Fe+3. Chemical composition of both minerals was

  7. Constraint monitoring in TOSCA

    NASA Technical Reports Server (NTRS)

    Beck, Howard

    1992-01-01

    The Job-Shop Scheduling Problem (JSSP) deals with the allocation of resources over time to factory operations. Allocations are subject to various constraints (e.g., production precedence relationships, factory capacity constraints, and limits on the allowable number of machine setups) which must be satisfied for a schedule to be valid. The identification of constraint violations and the monitoring of constraint threats plays a vital role in schedule generation in terms of the following: (1) directing the scheduling process; and (2) informing scheduling decisions. This paper describes a general mechanism for identifying constraint violations and monitoring threats to the satisfaction of constraints throughout schedule generation.

  8. Multiple Genetic Analysis System-Based Antibiotic Susceptibility Testing in Helicobacter pylori and High Eradication Rate With Phenotypic Resistance-Guided Quadruple Therapy.

    PubMed

    Dong, Fangyuan; Ji, Danian; Huang, Renxiang; Zhang, Fan; Huang, Yiqin; Xiang, Ping; Kong, Mimi; Nan, Li; Zeng, Xianping; Wu, Yong; Bao, Zhijun

    2015-11-01

    Antibiotics resistance in Helicobacter pylori (H. pylori) is the major factor for eradication failure. Molecular tests including fluorescence in situ hybridization, PCR-restriction fragment length polymorphism, and dual priming oligonucleotide-PCR (DPO-PCR) play critical roles in the detection of antibiotic susceptibility; however, limited knowledge is known about application of multiple genetic analysis system (MGAS) in the area of H. pylori identification and antibiotics resistance detection.The aim of this study is to determine the antibiotics resistance using different molecular tests and evaluate the treatment outcomes of E-test-based genotypic resistance.A total of 297 patients with dyspepsia complaint were recruited for gastroscopies. Ninety patients with H. pylori culture positive were randomly divided into 2 groups (test group and control group). E-test, general PCR, and MGAS assay were performed in test group. Patients in control group were treated with empirical therapy (rabeprazole + bismuth potassium citrate + amoxicillin [AMX] + clarithromycin [CLR]), whereas patients in test group received quadruple therapy based on E-test results twice daily for 14 consecutive days. The eradication effect of H. pylori was confirmed by C-urea breath test after at least 4 weeks when treatment was finished.Rapid urease test showed 46.5% (128/297) patients with H. pylori infection, whereas 30.3% (90/297) patients were H. pylori culture positive. E-test showed that H. pylori primary resistance rate to CLR, AMX, metronidazole, tetracycline, and levofloxacin (LVX) was 40.0% (18/45), 4.4% (2/45), 53.3% (24/45), 0% (0/45), and 55.6% (25/45), respectively. In addition, there are many multidrug resistant (MDR) phenotypes, and the MDR strains have higher minimum inhibitory concentration than their single-drug resistant counterparts. Considering E-test as the reference test, the sensitivities of general PCR and MGAS in detecting CLR resistance were 83.3% (15/18) and 94.4% (17

  9. Multiple Genetic Analysis System-Based Antibiotic Susceptibility Testing in Helicobacter pylori and High Eradication Rate With Phenotypic Resistance-Guided Quadruple Therapy

    PubMed Central

    Dong, Fangyuan; Ji, Danian; Huang, Renxiang; Zhang, Fan; Huang, Yiqin; Xiang, Ping; Kong, Mimi; Nan, Li; Zeng, Xianping; Wu, Yong; Bao, Zhijun

    2015-01-01

    Abstract Antibiotics resistance in Helicobacter pylori (H. pylori) is the major factor for eradication failure. Molecular tests including fluorescence in situ hybridization, PCR-restriction fragment length polymorphism, and dual priming oligonucleotide-PCR (DPO-PCR) play critical roles in the detection of antibiotic susceptibility; however, limited knowledge is known about application of multiple genetic analysis system (MGAS) in the area of H. pylori identification and antibiotics resistance detection. The aim of this study is to determine the antibiotics resistance using different molecular tests and evaluate the treatment outcomes of E-test-based genotypic resistance. A total of 297 patients with dyspepsia complaint were recruited for gastroscopies. Ninety patients with H. pylori culture positive were randomly divided into 2 groups (test group and control group). E-test, general PCR, and MGAS assay were performed in test group. Patients in control group were treated with empirical therapy (rabeprazole + bismuth potassium citrate + amoxicillin [AMX] + clarithromycin [CLR]), whereas patients in test group received quadruple therapy based on E-test results twice daily for 14 consecutive days. The eradication effect of H. pylori was confirmed by 13C-urea breath test after at least 4 weeks when treatment was finished. Rapid urease test showed 46.5% (128/297) patients with H. pylori infection, whereas 30.3% (90/297) patients were H. pylori culture positive. E-test showed that H. pylori primary resistance rate to CLR, AMX, metronidazole, tetracycline, and levofloxacin (LVX) was 40.0% (18/45), 4.4% (2/45), 53.3% (24/45), 0% (0/45), and 55.6% (25/45), respectively. In addition, there are many multidrug resistant (MDR) phenotypes, and the MDR strains have higher minimum inhibitory concentration than their single-drug resistant counterparts. Considering E-test as the reference test, the sensitivities of general PCR and MGAS in detecting CLR resistance were 83.3% (15

  10. Genetics Home Reference: adiposis dolorosa

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions adiposis dolorosa adiposis dolorosa Enable ...

  11. Genetics Home Reference: Canavan disease

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions Canavan disease Canavan disease Enable ...

  12. Genetics Home Reference: Carney complex

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions Carney complex Carney complex Enable ...

  13. Genetics Home Reference: cardiofaciocutaneous syndrome

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions cardiofaciocutaneous syndrome cardiofaciocutaneous syndrome Enable ...

  14. Genetics Home Reference: Caffey disease

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions Caffey disease Caffey disease Enable ...

  15. Constraint Based Modeling Going Multicellular

    PubMed Central

    Martins Conde, Patricia do Rosario; Sauter, Thomas; Pfau, Thomas

    2016-01-01

    Constraint based modeling has seen applications in many microorganisms. For example, there are now established methods to determine potential genetic modifications and external interventions to increase the efficiency of microbial strains in chemical production pipelines. In addition, multiple models of multicellular organisms have been created including plants and humans. While initially the focus here was on modeling individual cell types of the multicellular organism, this focus recently started to switch. Models of microbial communities, as well as multi-tissue models of higher organisms have been constructed. These models thereby can include different parts of a plant, like root, stem, or different tissue types in the same organ. Such models can elucidate details of the interplay between symbiotic organisms, as well as the concerted efforts of multiple tissues and can be applied to analyse the effects of drugs or mutations on a more systemic level. In this review we give an overview of the recent development of multi-tissue models using constraint based techniques and the methods employed when investigating these models. We further highlight advances in combining constraint based models with dynamic and regulatory information and give an overview of these types of hybrid or multi-level approaches. PMID:26904548

  16. Constraint Based Modeling Going Multicellular.

    PubMed

    Martins Conde, Patricia do Rosario; Sauter, Thomas; Pfau, Thomas

    2016-01-01

    Constraint based modeling has seen applications in many microorganisms. For example, there are now established methods to determine potential genetic modifications and external interventions to increase the efficiency of microbial strains in chemical production pipelines. In addition, multiple models of multicellular organisms have been created including plants and humans. While initially the focus here was on modeling individual cell types of the multicellular organism, this focus recently started to switch. Models of microbial communities, as well as multi-tissue models of higher organisms have been constructed. These models thereby can include different parts of a plant, like root, stem, or different tissue types in the same organ. Such models can elucidate details of the interplay between symbiotic organisms, as well as the concerted efforts of multiple tissues and can be applied to analyse the effects of drugs or mutations on a more systemic level. In this review we give an overview of the recent development of multi-tissue models using constraint based techniques and the methods employed when investigating these models. We further highlight advances in combining constraint based models with dynamic and regulatory information and give an overview of these types of hybrid or multi-level approaches.

  17. Constraint Based Modeling Going Multicellular.

    PubMed

    Martins Conde, Patricia do Rosario; Sauter, Thomas; Pfau, Thomas

    2016-01-01

    Constraint based modeling has seen applications in many microorganisms. For example, there are now established methods to determine potential genetic modifications and external interventions to increase the efficiency of microbial strains in chemical production pipelines. In addition, multiple models of multicellular organisms have been created including plants and humans. While initially the focus here was on modeling individual cell types of the multicellular organism, this focus recently started to switch. Models of microbial communities, as well as multi-tissue models of higher organisms have been constructed. These models thereby can include different parts of a plant, like root, stem, or different tissue types in the same organ. Such models can elucidate details of the interplay between symbiotic organisms, as well as the concerted efforts of multiple tissues and can be applied to analyse the effects of drugs or mutations on a more systemic level. In this review we give an overview of the recent development of multi-tissue models using constraint based techniques and the methods employed when investigating these models. We further highlight advances in combining constraint based models with dynamic and regulatory information and give an overview of these types of hybrid or multi-level approaches. PMID:26904548

  18. Genes and Surroundings: Teacher's Guide.

    ERIC Educational Resources Information Center

    Biological Sciences Curriculum Study, Colorado Springs, CO. Center for Education in Human and Medical Genetics.

    This teacher's guide is intended to be used with "Genes and Surroundings," an activity unit on human and medical genetics for junior high and middle school students. The unit emphasizes variability and diversity in genetics and is organized around five themes: (1) individuality; (2) continuity; (3) variability in relation to others; (4)…

  19. Creating Positive Task Constraints

    ERIC Educational Resources Information Center

    Mally, Kristi K.

    2006-01-01

    Constraints are characteristics of the individual, the task, or the environment that mold and shape movement choices and performances. Constraints can be positive--encouraging proficient movements or negative--discouraging movement or promoting ineffective movements. Physical educators must analyze, evaluate, and determine the effect various…

  20. Constraint Reasoning Over Strings

    NASA Technical Reports Server (NTRS)

    Koga, Dennis (Technical Monitor); Golden, Keith; Pang, Wanlin

    2003-01-01

    This paper discusses an approach to representing and reasoning about constraints over strings. We discuss how many string domains can often be concisely represented using regular languages, and how constraints over strings, and domain operations on sets of strings, can be carried out using this representation.

  1. Credit Constraints in Education

    ERIC Educational Resources Information Center

    Lochner, Lance; Monge-Naranjo, Alexander

    2012-01-01

    We review studies of the impact of credit constraints on the accumulation of human capital. Evidence suggests that credit constraints have recently become important for schooling and other aspects of households' behavior. We highlight the importance of early childhood investments, as their response largely determines the impact of credit…

  2. Reduction of Constraints: Applicability of the Homogeneity Constraint for Macrobatch 3

    SciTech Connect

    Peeler, D.K.

    2001-02-15

    The Product Composition Control System (PCCS) is used to determine the acceptability of each batch of Defense Waste Processing Facility (DWPF) melter feed in the Slurry Mix Evaporator (SME). This control system imposes several constraints on the composition of the contents of the SME to define acceptability. These constraints relate process or product properties to composition via prediction models. A SME batch is deemed acceptable if its sample composition measurements lead to acceptable property predictions after accounting for modeling, measurement and analytic uncertainties. The baseline document guiding the use of these data and models is ''SME Acceptability Determination for DWPF Process Control (U)'' by Brown and Postles [1996]. A minimum of three PCCS constraints support the prediction of the glass durability from a given SME batch. The Savannah River Technology Center (SRTC) is reviewing all of the PCCS constraints associated with durability. The purpose of this review is to revisit these constraints in light of the additional knowledge gained since the beginning of radioactive operations at DWPF and to identify any supplemental studies needed to amplify this knowledge so that redundant or overly conservative constraints can be eliminated or replaced by more appropriate constraints.

  3. Accounting 10-20-30. Business Education Curriculum Guide.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Curriculum Branch.

    This curriculum guide is one of nine such guides developed for an Alberta high school business education program. Its content covers the main subject area or strand of accounting. Subject to the constraints outlined in the guide, the modules are to be formatted into three- or four-credit courses within each strand. Introductory materials include a…

  4. Computer Processing 10-20-30. Business Education Curriculum Guide.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Curriculum Branch.

    This curriculum guide is one of nine such guides developed for an Alberta high school business education program. Its content covers the main subject area or strand of computer processing. Subject to the constraints outlined in the guide, the modules are to be formatted into three- or four-credit courses within each strand. Introductory materials…

  5. Marketing 20-30. Business Education Curriculum Guide.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Curriculum Branch.

    This curriculum guide is one of nine such guides developed for an Alberta high school business education program. Its content covers the main subject area or strand of marketing. Subject to the constraints outlined in the guide, the modules are to be formatted into three- or four-credit courses within each strand. Introductory materials include a…

  6. Neutron guide

    DOEpatents

    Greene, Geoffrey L.

    1999-01-01

    A neutron guide in which lengths of cylindrical glass tubing have rectangular glass plates properly dimensioned to allow insertion into the cylindrical glass tubing so that a sealed geometrically precise polygonal cross-section is formed in the cylindrical glass tubing. The neutron guide provides easier alignment between adjacent sections than do the neutron guides of the prior art.

  7. Rod guide

    SciTech Connect

    Sable, D.E.

    1988-11-29

    This patent describes a rod guide assembly for a sucker rod longitudinally reciprocably movable in a well flow conductor comprising: a pair of longitudinally spaced upper and lower stops rigidly secured to a sucker rod; and a guide body movably mounted on the rod between the stops. The stops being spaced from each other a distance slightly greater than the length of the guide body, the upper stop engaging the guide body to move the guide body downwardly with the rod after an initial short downward movement of the rod after initiation of each downward movement of the rod and the lower stop engaging the guide body to move the second guide body upwardly with the rod after initial short upward movement of the rod after initiation of each upward movement of the rod during the longitudinal reciprocatory movement of the rod in a well flow conductor.

  8. Discovery and Structure-Guided Optimization of Diarylmethanesulfonamide Disrupters of Glucokinase-Glucokinase Regulatory Protein (GK-GKRP) Binding: Strategic Use of a N → S (nN → σ*S-X) Interaction for Conformational Constraint.

    PubMed

    Pennington, Lewis D; Bartberger, Michael D; Croghan, Michael D; Andrews, Kristin L; Ashton, Kate S; Bourbeau, Matthew P; Chen, Jie; Chmait, Samer; Cupples, Rod; Fotsch, Christopher; Helmering, Joan; Hong, Fang-Tsao; Hungate, Randall W; Jordan, Steven R; Kong, Ke; Liu, Longbin; Michelsen, Klaus; Moyer, Carolyn; Nishimura, Nobuko; Norman, Mark H; Reichelt, Andreas; Siegmund, Aaron C; Sivits, Glenn; Tadesse, Seifu; Tegley, Christopher M; Van, Gwyneth; Yang, Kevin C; Yao, Guomin; Zhang, Jiandong; Lloyd, David J; Hale, Clarence; St Jean, David J

    2015-12-24

    The HTS-based discovery and structure-guided optimization of a novel series of GKRP-selective GK-GKRP disrupters are revealed. Diarylmethanesulfonamide hit 6 (hGK-hGKRP IC50 = 1.2 μM) was optimized to lead compound 32 (AMG-0696; hGK-hGKRP IC50 = 0.0038 μM). A stabilizing interaction between a nitrogen atom lone pair and an aromatic sulfur system (nN → σ*S-X) in 32 was exploited to conformationally constrain a biaryl linkage and allow contact with key residues in GKRP. Lead compound 32 was shown to induce GK translocation from the nucleus to the cytoplasm in rats (IHC score = 0; 10 mg/kg po, 6 h) and blood glucose reduction in mice (POC = -45%; 100 mg/kg po, 3 h). X-ray analyses of 32 and several precursors bound to GKRP were also obtained. This novel disrupter of GK-GKRP binding enables further exploration of GKRP as a potential therapeutic target for type II diabetes and highlights the value of exploiting unconventional nonbonded interactions in drug design.

  9. Effect of spatial constraints on Hardy-Weinberg equilibrium

    PubMed Central

    Chen, Yi-Shin; Su, Yi-Cheng; Pan, Wei

    2016-01-01

    Panmixia is a key issue in maintaining genetic diversity, which facilitates evolutionary potential during environmental changes. Additionally, conservation biologists suggest the importance of avoiding small or subdivided populations, which are prone to losing genetic diversity. In this paper, computer simulations were performed to the genetic drift of neutral alleles in random mating populations with or without spatial constraints by randomly choosing a mate among the closest neighbours. The results demonstrated that the number of generations required for the neutral allele to become homozygous (Th) varied proportionally to the population size and also strongly correlated with spatial constraints. The average Th for populations of the same size with spatial constraints was approximately one-and-a-half times longer than without constraints. With spatial constraints, homozygous population clusters formed, which reduced local diversity but preserved global diversity. Therefore, panmixia might be harmful in preserving the genetic diversity of an entire population. The results also suggested that the gene flow or gene exchange among the subdivided populations must be carefully processed to restrict diseases transmission or death during transportation and to monitor the genetic diversity. The application of this concept to similar systems, such as information transfer among peers, is also discussed. PMID:26771073

  10. Constraint algebra in bigravity

    SciTech Connect

    Soloviev, V. O.

    2015-07-15

    The number of degrees of freedom in bigravity theory is found for a potential of general form and also for the potential proposed by de Rham, Gabadadze, and Tolley (dRGT). This aim is pursued via constructing a Hamiltonian formalismand studying the Poisson algebra of constraints. A general potential leads to a theory featuring four first-class constraints generated by general covariance. The vanishing of the respective Hessian is a crucial property of the dRGT potential, and this leads to the appearance of two additional second-class constraints and, hence, to the exclusion of a superfluous degree of freedom—that is, the Boulware—Deser ghost. The use of a method that permits avoiding an explicit expression for the dRGT potential is a distinctive feature of the present study.

  11. The photogrammetric inner constraints

    NASA Astrophysics Data System (ADS)

    Dermanis, Athanasios

    A derivation of the complete inner constraints, which are required for obtaining "free network" solutions in close-range photogrammetry, is presented. The inner constraints are derived analytically for the bundle method, by exploiting the fact that the rows of their coefficient matrix from a basis for the null subspace of the design matrix used in the linearized observation equations. The derivation is independent of any particular choice of rotational parameters and examples are given for three types of rotation angles used in photogrammetry, as well as for the Rodriguez elements. A convenient algorithm based on the use of the S-transformation is presented, for the computation of free solutions with either inner or partial inner constraints. This approach is finally compared with alternative approaches to free network solutions.

  12. Constraint algebra in bigravity

    NASA Astrophysics Data System (ADS)

    Soloviev, V. O.

    2015-07-01

    The number of degrees of freedom in bigravity theory is found for a potential of general form and also for the potential proposed by de Rham, Gabadadze, and Tolley (dRGT). This aim is pursued via constructing a Hamiltonian formalismand studying the Poisson algebra of constraints. A general potential leads to a theory featuring four first-class constraints generated by general covariance. The vanishing of the respective Hessian is a crucial property of the dRGT potential, and this leads to the appearance of two additional second-class constraints and, hence, to the exclusion of a superfluous degree of freedom—that is, the Boulware—Deser ghost. The use of a method that permits avoiding an explicit expression for the dRGT potential is a distinctive feature of the present study.

  13. Genetic structure of Pilosocereus gounellei (Cactaceae) as revealed by AFLP marker to guide proposals for improvement and restoration of degraded areas in Caatinga biome.

    PubMed

    Monteiro, E R; Strioto, D K; Meirelles, A C S; Mangolin, C A; Machado, M F P S

    2015-12-15

    Amplified fragment length polymorphism (AFLP) analysis was used to evaluate DNA polymorphism in Pilosocereus gounellei with the aim of differentiating samples grown in different Brazilian semiarid regions. Seven primer pairs were used to amplify 703 AFLP markers, of which 700 (99.21%) markers were polymorphic. The percentage of polymorphic markers ranged from 95.3% for the primer combination E-AAG/M-CTT to 100% for E-ACC/M-CAT, E-ACC/M-CAA, E-AGC/M-CAG, E-ACT/M-CTA, and E-AGG/M-CTG. The largest number of informative markers (126) was detected using the primer combination E-AAC/M-CTA. Polymorphism of the amplified DNA fragments ranged from 72.55% (in sample from Piauí State) to 82.79% (in samples from Rio Grande Norte State), with an average of 75.39%. Despite the high genetic diversity of AFLP markers in xiquexique, analysis using the STRUCTURE software identified relatively homogeneous clusters of xiquexique from the same location, indicating a differentiation at the molecular level, among the plant samples from different regions of the Caatinga biome. The AFLP methodology identified genetically homogeneous and contrasting plants, as well as plants from different regions with common DNA markers. Seeds from such plants can be used for further propagation of plants for establishment of biodiversity conservation units and restoration of degraded areas of the Caatinga biome.

  14. Genetic structure of Pilosocereus gounellei (Cactaceae) as revealed by AFLP marker to guide proposals for improvement and restoration of degraded areas in Caatinga biome.

    PubMed

    Monteiro, E R; Strioto, D K; Meirelles, A C S; Mangolin, C A; Machado, M F P S

    2015-01-01

    Amplified fragment length polymorphism (AFLP) analysis was used to evaluate DNA polymorphism in Pilosocereus gounellei with the aim of differentiating samples grown in different Brazilian semiarid regions. Seven primer pairs were used to amplify 703 AFLP markers, of which 700 (99.21%) markers were polymorphic. The percentage of polymorphic markers ranged from 95.3% for the primer combination E-AAG/M-CTT to 100% for E-ACC/M-CAT, E-ACC/M-CAA, E-AGC/M-CAG, E-ACT/M-CTA, and E-AGG/M-CTG. The largest number of informative markers (126) was detected using the primer combination E-AAC/M-CTA. Polymorphism of the amplified DNA fragments ranged from 72.55% (in sample from Piauí State) to 82.79% (in samples from Rio Grande Norte State), with an average of 75.39%. Despite the high genetic diversity of AFLP markers in xiquexique, analysis using the STRUCTURE software identified relatively homogeneous clusters of xiquexique from the same location, indicating a differentiation at the molecular level, among the plant samples from different regions of the Caatinga biome. The AFLP methodology identified genetically homogeneous and contrasting plants, as well as plants from different regions with common DNA markers. Seeds from such plants can be used for further propagation of plants for establishment of biodiversity conservation units and restoration of degraded areas of the Caatinga biome. PMID:26681043

  15. Genetics Home Reference: adenosine monophosphate deaminase deficiency

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions adenosine monophosphate deaminase deficiency adenosine ...

  16. Genetics Home Reference: Camurati-Engelmann disease

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions Camurati-Engelmann disease Camurati-Engelmann ...

  17. Genetics Home Reference: Cantú syndrome

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions Cantú syndrome Cantú syndrome Enable ...

  18. Genetics Home Reference: Buschke-Ollendorff syndrome

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions Buschke-Ollendorff syndrome Buschke-Ollendorff ...

  19. Background constraints in the infinite tension limit of the heterotic string

    NASA Astrophysics Data System (ADS)

    Azevedo, Thales; Jusinskas, Renann Lipinski

    2016-08-01

    In this work we investigate the classical constraints imposed on the supergravity and super Yang-Mills backgrounds in the α' → 0 limit of the heterotic string using the pure spinor formalism. Guided by the recently observed sectorization of the model, we show that all the ten-dimensional constraints are elegantly obtained from the single condition of nilpotency of the BRST charge.

  20. Breaking evolutionary constraint with a tradeoff ratchet

    PubMed Central

    de Vos, Marjon G. J.; Dawid, Alexandre; Sunderlikova, Vanda; Tans, Sander J.

    2015-01-01

    Epistatic interactions can frustrate and shape evolutionary change. Indeed, phenotypes may fail to evolve when essential mutations are only accessible through positive selection if they are fixed simultaneously. How environmental variability affects such constraints is poorly understood. Here, we studied genetic constraints in fixed and fluctuating environments using the Escherichia coli lac operon as a model system for genotype–environment interactions. We found that, in different fixed environments, all trajectories that were reconstructed by applying point mutations within the transcription factor–operator interface became trapped at suboptima, where no additional improvements were possible. Paradoxically, repeated switching between these same environments allows unconstrained adaptation by continuous improvements. This evolutionary mode is explained by pervasive cross-environmental tradeoffs that reposition the peaks in such a way that trapped genotypes can repeatedly climb ascending slopes and hence, escape adaptive stasis. Using a Markov approach, we developed a mathematical framework to quantify the landscape-crossing rates and show that this ratchet-like adaptive mechanism is robust in a wide spectrum of fluctuating environments. Overall, this study shows that genetic constraints can be overcome by environmental change and that cross-environmental tradeoffs do not necessarily impede but also, can facilitate adaptive evolution. Because tradeoffs and environmental variability are ubiquitous in nature, we speculate this evolutionary mode to be of general relevance. PMID:26567153

  1. Mechanical constraints imposed by 3D cellular geometry and arrangement modulate growth patterns in the Arabidopsis embryo.

    PubMed

    Bassel, George W; Stamm, Petra; Mosca, Gabriella; Barbier de Reuille, Pierre; Gibbs, Daniel J; Winter, Robin; Janka, Ales; Holdsworth, Michael J; Smith, Richard S

    2014-06-10

    Morphogenesis occurs in 3D space over time and is guided by coordinated gene expression programs. Here we use postembryonic development in Arabidopsis plants to investigate the genetic control of growth. We demonstrate that gene expression driving the production of the growth-stimulating hormone gibberellic acid and downstream growth factors is first induced within the radicle tip of the embryo. The center of cell expansion is, however, spatially displaced from the center of gene expression. Because the rapidly growing cells have very different geometry from that of those at the tip, we hypothesized that mechanical factors may contribute to this growth displacement. To this end we developed 3D finite-element method models of growing custom-designed digital embryos at cellular resolution. We used this framework to conceptualize how cell size, shape, and topology influence tissue growth and to explore the interplay of geometrical and genetic inputs into growth distribution. Our simulations showed that mechanical constraints are sufficient to explain the disconnect between the experimentally observed spatiotemporal patterns of gene expression and early postembryonic growth. The center of cell expansion is the position where genetic and mechanical facilitators of growth converge. We have thus uncovered a mechanism whereby 3D cellular geometry helps direct where genetically specified growth takes place.

  2. Constraining neutron guide optimizations with phase-space considerations

    NASA Astrophysics Data System (ADS)

    Bertelsen, Mads; Lefmann, Kim

    2016-09-01

    We introduce a method named the Minimalist Principle that serves to reduce the parameter space for neutron guide optimization when the required beam divergence is limited. The reduced parameter space will restrict the optimization to guides with a minimal neutron intake that are still theoretically able to deliver the maximal possible performance. The geometrical constraints are derived using phase-space propagation from moderator to guide and from guide to sample, while assuming that the optimized guides will achieve perfect transport of the limited neutron intake. Guide systems optimized using these constraints are shown to provide performance close to guides optimized without any constraints, however the divergence received at the sample is limited to the desired interval, even when the neutron transport is not limited by the supermirrors used in the guide. As the constraints strongly limit the parameter space for the optimizer, two control parameters are introduced that can be used to adjust the selected subspace, effectively balancing between maximizing neutron transport and avoiding background from unnecessary neutrons. One parameter is needed to describe the expected focusing abilities of the guide to be optimized, going from perfectly focusing to no correlation between position and velocity. The second parameter controls neutron intake into the guide, so that one can select exactly how aggressively the background should be limited. We show examples of guides optimized using these constraints which demonstrates the higher signal to noise than conventional optimizations. Furthermore the parameter controlling neutron intake is explored which shows that the simulated optimal neutron intake is close to the analytically predicted, when assuming that the guide is dominated by multiple scattering events.

  3. Dynamical Constraints on Exoplanets

    NASA Astrophysics Data System (ADS)

    Horner, Jonti; Wittenmyer, Robert A.; Tinney, Chris; Hinse, Tobias C.; Marshall, Jonathan P.

    2014-01-01

    Dynamical studies of new exoplanet systems are a critical component of the discovery and characterisation process. Such studies can provide firmer constraints on the parameters of the newly discovered planets, and may even reveal that the proposed planets do not stand up to dynamical scrutiny. Here, we demonstrate how dynamical studies can assist the characterisation of such systems through two examples: QS Virginis and HD 73526.

  4. Constraint-based scheduling

    NASA Technical Reports Server (NTRS)

    Zweben, Monte

    1991-01-01

    The GERRY scheduling system developed by NASA Ames with assistance from the Lockheed Space Operations Company, and the Lockheed Artificial Intelligence Center, uses a method called constraint based iterative repair. Using this technique, one encodes both hard rules and preference criteria into data structures called constraints. GERRY repeatedly attempts to improve schedules by seeking repairs for violated constraints. The system provides a general scheduling framework which is being tested on two NASA applications. The larger of the two is the Space Shuttle Ground Processing problem which entails the scheduling of all inspection, repair, and maintenance tasks required to prepare the orbiter for flight. The other application involves power allocations for the NASA Ames wind tunnels. Here the system will be used to schedule wind tunnel tests with the goal of minimizing power costs. In this paper, we describe the GERRY system and its applications to the Space Shuttle problem. We also speculate as to how the system would be used for manufacturing, transportation, and military problems.

  5. Constraint-based scheduling

    NASA Technical Reports Server (NTRS)

    Zweben, Monte

    1991-01-01

    The GERRY scheduling system developed by NASA Ames with assistance from the Lockheed Space Operations Company, and the Lockheed Artificial Intelligence Center, uses a method called constraint-based iterative repair. Using this technique, one encodes both hard rules and preference criteria into data structures called constraints. GERRY repeatedly attempts to improve schedules by seeking repairs for violated constraints. The system provides a general scheduling framework which is being tested on two NASA applications. The larger of the two is the Space Shuttle Ground Processing problem which entails the scheduling of all the inspection, repair, and maintenance tasks required to prepare the orbiter for flight. The other application involves power allocation for the NASA Ames wind tunnels. Here the system will be used to schedule wind tunnel tests with the goal of minimizing power costs. In this paper, we describe the GERRY system and its application to the Space Shuttle problem. We also speculate as to how the system would be used for manufacturing, transportation, and military problems.

  6. Constraint-based scheduling

    NASA Technical Reports Server (NTRS)

    Zweben, Monte

    1993-01-01

    The GERRY scheduling system developed by NASA Ames with assistance from the Lockheed Space Operations Company, and the Lockheed Artificial Intelligence Center, uses a method called constraint-based iterative repair. Using this technique, one encodes both hard rules and preference criteria into data structures called constraints. GERRY repeatedly attempts to improve schedules by seeking repairs for violated constraints. The system provides a general scheduling framework which is being tested on two NASA applications. The larger of the two is the Space Shuttle Ground Processing problem which entails the scheduling of all the inspection, repair, and maintenance tasks required to prepare the orbiter for flight. The other application involves power allocation for the NASA Ames wind tunnels. Here the system will be used to schedule wind tunnel tests with the goal of minimizing power costs. In this paper, we describe the GERRY system and its application to the Space Shuttle problem. We also speculate as to how the system would be used for manufacturing, transportation, and military problems.

  7. Pediatric genetic disorders of lens.

    PubMed

    Nihalani, Bharti R

    2014-12-01

    Pediatric genetic disorders of lens include various cataractous and non-cataractous anomalies. The purpose of this review is to help determine the genetic cause based on the lens appearance, ocular and systemic associations. Children with bilateral cataracts require a comprehensive history, ophthalmic and systemic examination to guide further genetic evaluation. With advancements in genetics, it is possible to determine the genetic mutations and assess phenotype genotype correlation in different lens disorders. The genetic diagnosis helps the families to better understand the disorder and develop realistic expectations as to the course of their child's disorder. PMID:27625879

  8. Pediatric genetic disorders of lens

    PubMed Central

    Nihalani, Bharti R.

    2014-01-01

    Pediatric genetic disorders of lens include various cataractous and non-cataractous anomalies. The purpose of this review is to help determine the genetic cause based on the lens appearance, ocular and systemic associations. Children with bilateral cataracts require a comprehensive history, ophthalmic and systemic examination to guide further genetic evaluation. With advancements in genetics, it is possible to determine the genetic mutations and assess phenotype genotype correlation in different lens disorders. The genetic diagnosis helps the families to better understand the disorder and develop realistic expectations as to the course of their child's disorder.

  9. The enigma of nonholonomic constraints

    NASA Astrophysics Data System (ADS)

    Flannery, M. R.

    2005-03-01

    The problems associated with the modification of Hamilton's principle to cover nonholonomic constraints by the application of the multiplier theorem of variational calculus are discussed. The reason for the problems is subtle and is discussed, together with the reason why the proper account of nonholonomic constraints is outside the scope of Hamilton's variational principle. However, linear velocity constraints remain within the scope of D'Alembert's principle. A careful and comprehensive analysis facilitates the resolution of the puzzling features of nonholonomic constraints.

  10. Structure Constraints in a Constraint-Based Planner

    NASA Technical Reports Server (NTRS)

    Pang, Wan-Lin; Golden, Keith

    2004-01-01

    In this paper we report our work on a new constraint domain, where variables can take structured values. Earth-science data processing (ESDP) is a planning domain that requires the ability to represent and reason about complex constraints over structured data, such as satellite images. This paper reports on a constraint-based planner for ESDP and similar domains. We discuss our approach for translating a planning problem into a constraint satisfaction problem (CSP) and for representing and reasoning about structured objects and constraints over structures.

  11. GPU-enabled projectile guidance for impact area constraints

    NASA Astrophysics Data System (ADS)

    Rogers, Jonathan

    2013-05-01

    Guided projectile engagement scenarios often involve impact area constraints, in which it may be less desirable to incur miss distance on one side of a target or within a specified boundary near the target area. Current projectile guidance schemes such as impact point predictors cannot handle these constraints within the guidance loop, and may produce dispersion patterns that are insensitive to these constraints. In this paper, a new projectile guidance law is proposed that leverages real-time Monte Carlo impact point prediction to continually evaluate the probability of violating impact area constraints. The desired aim point is then adjusted accordingly. Real-time Monte Carlo simulation is enabled within the feedback loop through use of graphics processing units (GPU's), which provide parallel pipelines through which a dispersion pattern can routinely be predicted. The result is a guidance law that can achieve minimum miss distance while avoiding impact area constraints. The new guidance law is described and formulated as a nonlinear optimization problem which is solved in real-time through massively-parallel Monte Carlo simulation. An example simulation is shown in which impact area constraints are enforced and the methodology of stochastic guidance is demonstrated. Finally, Monte Carlo simulations are shown which demonstrate the ability of the stochastic guidance scheme to avoid an arbitrary set of impact area constraints, generating an impact probability density function that optimally trades miss distance within the restricted impact area. The proposed guidance scheme has applications beyond smart weapons to include missiles, UAV's, and other autonomous systems.

  12. Deformation invariant bounding spheres for dynamic active constraints in surgery.

    PubMed

    Bowyer, Stuart A; Rodriguez Y Baena, Ferdinando

    2014-04-01

    Active constraints are collaborative robot control strategies, which can be used to guide a surgeon or protect delicate tissue structures during robot-assisted surgery. Tissue structures of interest often move and deform throughout a surgical intervention, and therefore, dynamic active constraints, which adapt and conform to these changes, are required. A fundamental element of an active constraint controller is the computation of the geometric relationship between the constraint geometry and the surgical instrument. For a static active constraint, there are a variety of computationally efficient methods for computing this relative configuration; however, for a dynamic active constraint, it becomes significantly more challenging. Deformation invariant bounding spheres are a novel bounding volume formulation, which can be used within a hierarchy to allow efficient proximity queries within dynamic active constraints. These bounding spheres are constructed in such a way that as the surface deforms, they do not require time-consuming rebuilds or updates, rather they are implicitly updated and continue to represent the underlying geometry as it changes. Experimental results show that performing proximity queries with deformation invariant bounding sphere hierarchies is faster than common methods from the literature when the deformation rate is within the range expected from conventional imaging systems. PMID:24622983

  13. Mitochondrial genetics

    PubMed Central

    Chinnery, Patrick Francis; Hudson, Gavin

    2013-01-01

    Introduction In the last 10 years the field of mitochondrial genetics has widened, shifting the focus from rare sporadic, metabolic disease to the effects of mitochondrial DNA (mtDNA) variation in a growing spectrum of human disease. The aim of this review is to guide the reader through some key concepts regarding mitochondria before introducing both classic and emerging mitochondrial disorders. Sources of data In this article, a review of the current mitochondrial genetics literature was conducted using PubMed (http://www.ncbi.nlm.nih.gov/pubmed/). In addition, this review makes use of a growing number of publically available databases including MITOMAP, a human mitochondrial genome database (www.mitomap.org), the Human DNA polymerase Gamma Mutation Database (http://tools.niehs.nih.gov/polg/) and PhyloTree.org (www.phylotree.org), a repository of global mtDNA variation. Areas of agreement The disruption in cellular energy, resulting from defects in mtDNA or defects in the nuclear-encoded genes responsible for mitochondrial maintenance, manifests in a growing number of human diseases. Areas of controversy The exact mechanisms which govern the inheritance of mtDNA are hotly debated. Growing points Although still in the early stages, the development of in vitro genetic manipulation could see an end to the inheritance of the most severe mtDNA disease. PMID:23704099

  14. Asteroseismic constraints for Gaia

    NASA Astrophysics Data System (ADS)

    Creevey, O. L.; Thévenin, F.

    2012-12-01

    Distances from the Gaia mission will no doubt improve our understanding of stellar physics by providing an excellent constraint on the luminosity of the star. However, it is also clear that high precision stellar properties from, for example, asteroseismology, will also provide a needed input constraint in order to calibrate the methods that Gaia will use, e.g. stellar models or GSP_Phot. For solar-like stars (F, G, K IV/V), asteroseismic data delivers at the least two very important quantities: (1) the average large frequency separation < Δ ν > and (2) the frequency corresponding to the maximum of the modulated-amplitude spectrum ν_{max}. Both of these quantities are related directly to stellar parameters (radius and mass) and in particular their combination (gravity and density). We show how the precision in < Δ ν >, ν_{max}, and atmospheric parameters T_{eff} and [Fe/H] affect the determination of gravity (log g) for a sample of well-known stars. We find that log g can be determined within less than 0.02 dex accuracy for our sample while considering precisions in the data expected for V˜12 stars from Kepler data. We also derive masses and radii which are accurate to within 1σ of the accepted values. This study validates the subsequent use of all of the available asteroseismic data on solar-like stars from the Kepler field (>500 IV/V stars) in order to provide a very important constraint for Gaia calibration of GSP_Phot} through the use of log g. We note that while we concentrate on IV/V stars, both the CoRoT and Kepler fields contain asteroseismic data on thousands of giant stars which will also provide useful calibration measures.

  15. Superresolution via sparsity constraints

    NASA Technical Reports Server (NTRS)

    Donoho, David L.

    1992-01-01

    The problem of recovering a measure mu supported on a lattice of span Delta is considered under the condition that measurements are only available concerning the Fourier Transform at frequencies of Omega or less. If Omega is much smaller than the Nyquist frequency pi/Delta and the measurements are noisy, then stable recovery of mu is generally impossible. It is shown here that if, in addition, it is known that mu satisfies certain sparsity constraints, then stable recovery is possible. This finding validates practical efforts in spectroscopy, seismic prospecting, and astronomy to provide superresolution by imposing support limitations in reconstruction.

  16. Performance constraints in decathletes.

    PubMed

    Van Damme, Raoul; Wilson, Robbie S; Vanhooydonck, Bieke; Aerts, Peter

    2002-02-14

    Physical performance by vertebrates is thought to be constrained by trade-offs between antagonistic pairs of ecologically relevant traits and between conflicting specialist and generalist phenotypes, but there is surprisingly little evidence to support this reasoning. Here we analyse the performance of world-class athletes in standardized decathlon events and find that it is subject to both types of trade-off, after correction has been made for differences between athletes in general ability across all 10 events. These trade-offs may have imposed important constraints on the evolution of physical performance in humans and other vertebrates. PMID:11845199

  17. On heterotic model constraints

    NASA Astrophysics Data System (ADS)

    Bouchard, Vincent; Donagi, Ron

    2008-08-01

    The constraints imposed on heterotic compactifications by global consistency and phenomenology seem to be very finely balanced. We show that weakening these constraints, as was proposed in some recent works, is likely to lead to frivolous results. In particular, we construct an infinite set of such frivolous models having precisely the massless spectrum of the MSSM and other quasi-realistic features. Only one model in this infinite collection (the one constructed in [8]) is globally consistent and supersymmetric. The others might be interpreted as being anomalous, or as non-supersymmetric models, or as local models that cannot be embedded in a global one. We also show that the strongly coupled model of [8] can be modified to a perturbative solution with stable SU(4) or SU(5) bundles in the hidden sector. We finally propose a detailed exploration of heterotic vacua involving bundles on Calabi-Yau threefolds with Bbb Z6 Wilson lines; we obtain many more frivolous solutions, but none that are globally consistent and supersymmetric at the string scale.

  18. Symbolic Constraint Maintenance Grid

    NASA Technical Reports Server (NTRS)

    James, Mark

    2006-01-01

    Version 3.1 of Symbolic Constraint Maintenance Grid (SCMG) is a software system that provides a general conceptual framework for utilizing pre-existing programming techniques to perform symbolic transformations of data. SCMG also provides a language (and an associated communication method and protocol) for representing constraints on the original non-symbolic data. SCMG provides a facility for exchanging information between numeric and symbolic components without knowing the details of the components themselves. In essence, it integrates symbolic software tools (for diagnosis, prognosis, and planning) with non-artificial-intelligence software. SCMG executes a process of symbolic summarization and monitoring of continuous time series data that are being abstractly represented as symbolic templates of information exchange. This summarization process enables such symbolic- reasoning computing systems as artificial- intelligence planning systems to evaluate the significance and effects of channels of data more efficiently than would otherwise be possible. As a result of the increased efficiency in representation, reasoning software can monitor more channels and is thus able to perform monitoring and control functions more effectively.

  19. Comparative population genomics of the Borrelia burgdorferi species complex reveals high degree of genetic isolation among species and underscores benefits and constraints to studying intra-specific epidemiological processes.

    PubMed

    Jacquot, Maude; Gonnet, Mathieu; Ferquel, Elisabeth; Abrial, David; Claude, Alexandre; Gasqui, Patrick; Choumet, Valérie; Charras-Garrido, Myriam; Garnier, Martine; Faure, Benjamin; Sertour, Natacha; Dorr, Nelly; De Goër, Jocelyn; Vourc'h, Gwenaël; Bailly, Xavier

    2014-01-01

    Lyme borreliosis, one of the most frequently contracted zoonotic diseases in the Northern Hemisphere, is caused by bacteria belonging to different genetic groups within the Borrelia burgdorferi species complex, which are transmitted by ticks among various wildlife reservoirs, such as small mammals and birds. These features make the Borrelia burgdorferi species complex an attractive biological model that can be used to study the diversification and the epidemiology of endemic bacterial pathogens. We investigated the potential of population genomic approaches to study these processes. Sixty-three strains belonging to three species within the Borrelia burgdorferi complex were isolated from questing ticks in Alsace (France), a region where Lyme disease is highly endemic. We first aimed to characterize the degree of genetic isolation among the species sampled. Phylogenetic and coalescent-based analyses revealed clear delineations: there was a ∼50 fold difference between intra-specific and inter-specific recombination rates. We then investigated whether the population genomic data contained information of epidemiological relevance. In phylogenies inferred using most of the genome, conspecific strains did not cluster in clades. These results raise questions about the relevance of different strategies when investigating pathogen epidemiology. For instance, here, both classical analytic approaches and phylodynamic simulations suggested that population sizes and migration rates were higher in B. garinii populations, which are normally associated with birds, than in B. burgdorferi s.s. populations. The phylogenetic analyses of the infection-related ospC gene and its flanking region provided additional support for this finding. Traces of recombination among the B. burgdorferi s.s. lineages and lineages associated with small mammals were found, suggesting that they shared the same hosts. Altogether, these results provide baseline evidence that can be used to formulate

  20. Medication Guide

    MedlinePlus

    ... Quit Smoking Benefits of Quitting Health Effects of Smoking Secondhand Smoke Withdrawal Ways to Quit QuitGuide Pregnancy & Motherhood Pregnancy & Motherhood Before Your Baby is Born From Birth to 2 Years Quitting for Two SmokefreeMom Healthy Kids Parenting & ... Weight Management Weight Management ...

  1. Homebuyer's Guide.

    ERIC Educational Resources Information Center

    Sindt, Roger P.; Harris, Jack

    Designed to assist prospective buyers in making such important decisions as whether to buy a new or older home and within what price range, the guide provides information on the purchase process. Discussion of the purchase process covers the life-cycle costs (recurring homeownership costs that must be met every month); selection of a home;…

  2. Freestyle Guide.

    ERIC Educational Resources Information Center

    Science Research Associates, Inc., Chicago, IL.

    This booklet serves as an introduction to the concept of Freestyle, a career awareness project designed to encourage nine- to twelve-year-olds to freely explore their interests, develop their skills, and choose their career paths. The booklet includes an explanation of the Freestyle project, goals, and components (t.v. programs, project guide,…

  3. Teachers Guide.

    ERIC Educational Resources Information Center

    Linsky, Ronald B.; Schnitger, Ronald L.

    This guide provides teachers with copies of the materials given to students participating in the oceanography program of the Orange County Floating Laboratory Program and provides information concerning colleges and universities offering courses in oceanography and marine science, source of films, and sources of publications concerning the Navy's…

  4. Solutions exist for constraints to household production and retention of animal food products.

    PubMed

    Brown, Dan L

    2003-11-01

    This article reviews constraints to household level animal source food production in developing countries and suggests solutions to some of these constraints. These constraints include land, labor, money, feed quality, water, disease, animal genetics, roles for animals beyond food production, grazing techniques and an understanding of the entire agricultural system at the household level. Better understanding of farming systems and the elements that comprise it which affect animal food production permits wise management of nutrient flows and enhanced sustainability. PMID:14672309

  5. Relative constraints and evolution

    NASA Astrophysics Data System (ADS)

    Ochoa, Juan G. Diaz

    2014-03-01

    Several mathematical models of evolving systems assume that changes in the micro-states are constrained to the search of an optimal value in a local or global objective function. However, the concept of evolution requires a continuous change in the environment and species, making difficult the definition of absolute optimal values in objective functions. In this paper, we define constraints that are not absolute but relative to local micro-states, introducing a rupture in the invariance of the phase space of the system. This conceptual basis is useful to define alternative mathematical models for biological (or in general complex) evolving systems. We illustrate this concept with a modified Ising model, which can be useful to understand and model problems like the somatic evolution of cancer.

  6. Evolutionary constraints or opportunities?

    PubMed

    Sharov, Alexei A

    2014-04-22

    Natural selection is traditionally viewed as a leading factor of evolution, whereas variation is assumed to be random and non-directional. Any order in variation is attributed to epigenetic or developmental constraints that can hinder the action of natural selection. In contrast I consider the positive role of epigenetic mechanisms in evolution because they provide organisms with opportunities for rapid adaptive change. Because the term "constraint" has negative connotations, I use the term "regulated variation" to emphasize the adaptive nature of phenotypic variation, which helps populations and species to survive and evolve in changing environments. The capacity to produce regulated variation is a phenotypic property, which is not described in the genome. Instead, the genome acts as a switchboard, where mostly random mutations switch "on" or "off" preexisting functional capacities of organism components. Thus, there are two channels of heredity: informational (genomic) and structure-functional (phenotypic). Functional capacities of organisms most likely emerged in a chain of modifications and combinations of more simple ancestral functions. The role of DNA has been to keep records of these changes (without describing the result) so that they can be reproduced in the following generations. Evolutionary opportunities include adjustments of individual functions, multitasking, connection between various components of an organism, and interaction between organisms. The adaptive nature of regulated variation can be explained by the differential success of lineages in macro-evolution. Lineages with more advantageous patterns of regulated variation are likely to produce more species and secure more resources (i.e., long-term lineage selection).

  7. Evolutionary constraints or opportunities?

    PubMed

    Sharov, Alexei A

    2014-09-01

    Natural selection is traditionally viewed as a leading factor of evolution, whereas variation is assumed to be random and non-directional. Any order in variation is attributed to epigenetic or developmental constraints that can hinder the action of natural selection. In contrast I consider the positive role of epigenetic mechanisms in evolution because they provide organisms with opportunities for rapid adaptive change. Because the term "constraint" has negative connotations, I use the term "regulated variation" to emphasize the adaptive nature of phenotypic variation, which helps populations and species to survive and evolve in changing environments. The capacity to produce regulated variation is a phenotypic property, which is not described in the genome. Instead, the genome acts as a switchboard, where mostly random mutations switch "on" or "off" preexisting functional capacities of organism components. Thus, there are two channels of heredity: informational (genomic) and structure-functional (phenotypic). Functional capacities of organisms most likely emerged in a chain of modifications and combinations of more simple ancestral functions. The role of DNA has been to keep records of these changes (without describing the result) so that they can be reproduced in the following generations. Evolutionary opportunities include adjustments of individual functions, multitasking, connection between various components of an organism, and interaction between organisms. The adaptive nature of regulated variation can be explained by the differential success of lineages in macro-evolution. Lineages with more advantageous patterns of regulated variation are likely to produce more species and secure more resources (i.e., long-term lineage selection).

  8. Neural constraints on learning

    PubMed Central

    Sadtler, Patrick T.; Quick, Kristin M.; Golub, Matthew D.; Chase, Steven M.; Ryu, Stephen I.; Tyler-Kabara, Elizabeth C.; Yu, Byron M.; Batista, Aaron P.

    2014-01-01

    Motor, sensory, and cognitive learning require networks of neurons to generate new activity patterns. Because some behaviors are easier to learn than others1,2, we wondered if some neural activity patterns are easier to generate than others. We asked whether the existing network constrains the patterns that a subset of its neurons is capable of exhibiting, and if so, what principles define the constraint. We employed a closed-loop intracortical brain-computer interface (BCI) learning paradigm in which Rhesus monkeys controlled a computer cursor by modulating neural activity patterns in primary motor cortex. Using the BCI paradigm, we could specify and alter how neural activity mapped to cursor velocity. At the start of each session, we observed the characteristic activity patterns of the recorded neural population. These patterns comprise a low-dimensional space (termed the intrinsic manifold, or IM) within the high-dimensional neural firing rate space. They presumably reflect constraints imposed by the underlying neural circuitry. We found that the animals could readily learn to proficiently control the cursor using neural activity patterns that were within the IM. However, animals were less able to learn to proficiently control the cursor using activity patterns that were outside of the IM. This result suggests that the existing structure of a network can shape learning. On the timescale of hours, it appears to be difficult to learn to generate neural activity patterns that are not consistent with the existing network structure. These findings offer a network-level explanation for the observation that we are more readily able to learn new skills when they are related to the skills that we already possess3,4. PMID:25164754

  9. [Genetics and genetic counseling].

    PubMed

    Izzi, Claudia; Liut, Francesca; Dallera, Nadia; Mazza, Cinzia; Magistroni, Riccardo; Savoldi, Gianfranco; Scolari, Francesco

    2016-01-01

    Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the most frequent genetic disease, characterized by progressive development of bilateral renal cysts. Two causative genes have been identified: PKD1 and PKD2. ADPKD phenotype is highly variable. Typically, ADPKD is an adult onset disease. However, occasionally, ADPKD manifests as very early onset disease. The phenotypic variability of ADPKD can be explained at three genetic levels: genic, allelic and gene modifier effects. Recent advances in molecular screening for PKD gene mutations and the introduction of the new next generation sequencing (NGS)- based genotyping approach have generated considerable improvement regarding the knowledge of genetic basis of ADPKD. The purpose of this article is to provide a comprehensive review of the genetics of ADPKD, focusing on new insights in genotype-phenotype correlation and exploring novel clinical approach to genetic testing. Evaluation of these new genetic information requires a multidisciplinary approach involving a nephrologist and a clinical geneticist. PMID:27067213

  10. Gradient Domain Guided Image Filtering.

    PubMed

    Kou, Fei; Chen, Weihai; Wen, Changyun; Li, Zhengguo

    2015-11-01

    Guided image filter (GIF) is a well-known local filter for its edge-preserving property and low computational complexity. Unfortunately, the GIF may suffer from halo artifacts, because the local linear model used in the GIF cannot represent the image well near some edges. In this paper, a gradient domain GIF is proposed by incorporating an explicit first-order edge-aware constraint. The edge-aware constraint makes edges be preserved better. To illustrate the efficiency of the proposed filter, the proposed gradient domain GIF is applied for single-image detail enhancement, tone mapping of high dynamic range images and image saliency detection. Both theoretical analysis and experimental results prove that the proposed gradient domain GIF can produce better resultant images, especially near the edges, where halos appear in the original GIF. PMID:26285153

  11. Introducing High School Students to Human Genetics.

    ERIC Educational Resources Information Center

    Haddow, Paula K.; And Others

    1988-01-01

    Considers six key concepts in human genetics in a question-and-answer format designed to help guide students to an understanding of the concept. Lists eight workshops in human genetics for high school biology teachers and four curriculum material packages on human genetics. (CW)

  12. Brain evolution and development: adaptation, allometry and constraint.

    PubMed

    Montgomery, Stephen H; Mundy, Nicholas I; Barton, Robert A

    2016-09-14

    Phenotypic traits are products of two processes: evolution and development. But how do these processes combine to produce integrated phenotypes? Comparative studies identify consistent patterns of covariation, or allometries, between brain and body size, and between brain components, indicating the presence of significant constraints limiting independent evolution of separate parts. These constraints are poorly understood, but in principle could be either developmental or functional. The developmental constraints hypothesis suggests that individual components (brain and body size, or individual brain components) tend to evolve together because natural selection operates on relatively simple developmental mechanisms that affect the growth of all parts in a concerted manner. The functional constraints hypothesis suggests that correlated change reflects the action of selection on distributed functional systems connecting the different sub-components, predicting more complex patterns of mosaic change at the level of the functional systems and more complex genetic and developmental mechanisms. These hypotheses are not mutually exclusive but make different predictions. We review recent genetic and neurodevelopmental evidence, concluding that functional rather than developmental constraints are the main cause of the observed patterns.

  13. Brain evolution and development: adaptation, allometry and constraint

    PubMed Central

    Barton, Robert A.

    2016-01-01

    Phenotypic traits are products of two processes: evolution and development. But how do these processes combine to produce integrated phenotypes? Comparative studies identify consistent patterns of covariation, or allometries, between brain and body size, and between brain components, indicating the presence of significant constraints limiting independent evolution of separate parts. These constraints are poorly understood, but in principle could be either developmental or functional. The developmental constraints hypothesis suggests that individual components (brain and body size, or individual brain components) tend to evolve together because natural selection operates on relatively simple developmental mechanisms that affect the growth of all parts in a concerted manner. The functional constraints hypothesis suggests that correlated change reflects the action of selection on distributed functional systems connecting the different sub-components, predicting more complex patterns of mosaic change at the level of the functional systems and more complex genetic and developmental mechanisms. These hypotheses are not mutually exclusive but make different predictions. We review recent genetic and neurodevelopmental evidence, concluding that functional rather than developmental constraints are the main cause of the observed patterns. PMID:27629025

  14. Brain evolution and development: adaptation, allometry and constraint.

    PubMed

    Montgomery, Stephen H; Mundy, Nicholas I; Barton, Robert A

    2016-09-14

    Phenotypic traits are products of two processes: evolution and development. But how do these processes combine to produce integrated phenotypes? Comparative studies identify consistent patterns of covariation, or allometries, between brain and body size, and between brain components, indicating the presence of significant constraints limiting independent evolution of separate parts. These constraints are poorly understood, but in principle could be either developmental or functional. The developmental constraints hypothesis suggests that individual components (brain and body size, or individual brain components) tend to evolve together because natural selection operates on relatively simple developmental mechanisms that affect the growth of all parts in a concerted manner. The functional constraints hypothesis suggests that correlated change reflects the action of selection on distributed functional systems connecting the different sub-components, predicting more complex patterns of mosaic change at the level of the functional systems and more complex genetic and developmental mechanisms. These hypotheses are not mutually exclusive but make different predictions. We review recent genetic and neurodevelopmental evidence, concluding that functional rather than developmental constraints are the main cause of the observed patterns. PMID:27629025

  15. On Constraints in Assembly Planning

    SciTech Connect

    Calton, T.L.; Jones, R.E.; Wilson, R.H.

    1998-12-17

    Constraints on assembly plans vary depending on product, assembly facility, assembly volume, and many other factors. Assembly costs and other measures to optimize vary just as widely. To be effective, computer-aided assembly planning systems must allow users to express the plan selection criteria that appIy to their products and production environments. We begin this article by surveying the types of user criteria, both constraints and quality measures, that have been accepted by assembly planning systems to date. The survey is organized along several dimensions, including strategic vs. tactical criteria; manufacturing requirements VS. requirements of the automated planning process itself and the information needed to assess compliance with each criterion. The latter strongly influences the efficiency of planning. We then focus on constraints. We describe a framework to support a wide variety of user constraints for intuitive and efficient assembly planning. Our framework expresses all constraints on a sequencing level, specifying orders and conditions on part mating operations in a number of ways. Constraints are implemented as simple procedures that either accept or reject assembly operations proposed by the planner. For efficiency, some constraints are supplemented with special-purpose modifications to the planner's algorithms. Fast replanning enables an interactive plan-view-constrain-replan cycle that aids in constraint discovery and documentation. We describe an implementation of the framework in a computer-aided assembly planning system and experiments applying the system to a number of complex assemblies, including one with 472 parts.

  16. Credit Constraints for Higher Education

    ERIC Educational Resources Information Center

    Solis, Alex

    2012-01-01

    This paper exploits a natural experiment that produces exogenous variation on credit access to determine the effect on college enrollment. The paper assess how important are credit constraints to explain the gap in college enrollment by family income, and what would be the gap if credit constraints are eliminated. Progress in college and dropout…

  17. Fixed Costs and Hours Constraints

    ERIC Educational Resources Information Center

    Johnson, William R.

    2011-01-01

    Hours constraints are typically identified by worker responses to questions asking whether they would prefer a job with more hours and more pay or fewer hours and less pay. Because jobs with different hours but the same rate of pay may be infeasible when there are fixed costs of employment or mandatory overtime premia, the constraint in those…

  18. Generalizing Atoms in Constraint Logic

    NASA Technical Reports Server (NTRS)

    Page, C. David, Jr.; Frisch, Alan M.

    1991-01-01

    This paper studies the generalization of atomic formulas, or atoms, that are augmented with constraints on or among their terms. The atoms may also be viewed as definite clauses whose antecedents express the constraints. Atoms are generalized relative to a body of background information about the constraints. This paper first examines generalization of atoms with only monadic constraints. The paper develops an algorithm for the generalization task and discusses algorithm complexity. It then extends the algorithm to apply to atoms with constraints of arbitrary arity. The paper also presents semantic properties of the generalizations computed by the algorithms, making the algorithms applicable to such problems as abduction, induction, and knowledge base verification. The paper emphasizes the application to induction and presents a pac-learning result for constrained atoms.

  19. Algorithms for reactions of nonholonomic constraints and servo-constraints

    NASA Astrophysics Data System (ADS)

    Slawianowski, J. J.

    Various procedures for deriving equations of motion of constrained mechanical systems are discussed and compared. A geometric interpretation of the procedures is given, stressing both linear and nonlinear nonholonomic constraints. Certain qualitative differences are analyzed between models of nonholonomic dynamics based on different procedures. Two algorithms of particular interest are: (1) the d'Alembert principle and its Appell-Tshetajev generalization, and (2) the variational Hamiltonian principle with subsidiary conditions. It is argued that the Hamiltonian principle, although not accepted in traditional technical applications, is more promising in generalizations concerning systems with higher differential constraints, or the more general functional constraints appearing in feedback and control systems.

  20. Genetics Home Reference: carbamoyl phosphate synthetase I deficiency

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions carbamoyl phosphate synthetase I deficiency ...

  1. Medical genetics

    SciTech Connect

    Nora, J.J.; Fraser, F.C.

    1989-01-01

    This book presents a discussion of medical genetics for the practitioner treating or counseling patients with genetic disease. It includes a discussion of the relationship of heredity and diseases, the chromosomal basis for heredity, gene frequencies, and genetics of development and maldevelopment. The authors also focus on teratology, somatic cell genetics, genetics and cancer, genetics of behavior.

  2. Evolutionary constraints or opportunities?

    PubMed Central

    Sharov, Alexei A.

    2014-01-01

    Natural selection is traditionally viewed as a leading factor of evolution, whereas variation is assumed to be random and non-directional. Any order in variation is attributed to epigenetic or developmental constraints that can hinder the action of natural selection. In contrast I consider the positive role of epigenetic mechanisms in evolution because they provide organisms with opportunities for rapid adaptive change. Because the term “constraint” has negative connotations, I use the term “regulated variation” to emphasize the adaptive nature of phenotypic variation, which helps populations and species to survive and evolve in changing environments. The capacity to produce regulated variation is a phenotypic property, which is not described in the genome. Instead, the genome acts as a switchboard, where mostly random mutations switch “on” or “off” preexisting functional capacities of organism components. Thus, there are two channels of heredity: informational (genomic) and structure-functional (phenotypic). Functional capacities of organisms most likely emerged in a chain of modifications and combinations of more simple ancestral functions. The role of DNA has been to keep records of these changes (without describing the result) so that they can be reproduced in the following generations. Evolutionary opportunities include adjustments of individual functions, multitasking, connection between various components of an organism, and interaction between organisms. The adaptive nature of regulated variation can be explained by the differential success of lineages in macro-evolution. Lineages with more advantageous patterns of regulated variation are likely to produce more species and secure more resources (i.e., long-term lineage selection). PMID:24769155

  3. Federal constraints: earned or unearned?

    PubMed

    Chalkley, D T

    1977-08-01

    The author discusses the evolution of federal constraints on medical, behavioral, and social science research. There has been only one court decision related to behavioral research and none in medical research. The burden of consent procedures can be lightened somewhat by careful consideration of the potential risks and nature of the research; questions are presented that can be used to determine whether constraints apply. The author notes that although there are good reasons for regulations in both behavioral and medical research, the appropriateness of current and proposed constraints is still a matter of debate.

  4. Resource allocation using constraint propagation

    NASA Technical Reports Server (NTRS)

    Rogers, John S.

    1990-01-01

    The concept of constraint propagation was discussed. Performance increases are possible with careful application of these constraint mechanisms. The degree of performance increase is related to the interdependence of the different activities resource usage. Although this method of applying constraints to activities and resources is often beneficial, it is obvious that this is no panacea cure for the computational woes that are experienced by dynamic resource allocation and scheduling problems. A combined effort for execution optimization in all areas of the system during development and the selection of the appropriate development environment is still the best method of producing an efficient system.

  5. A constraint consensus memetic algorithm for solving constrained optimization problems

    NASA Astrophysics Data System (ADS)

    Hamza, Noha M.; Sarker, Ruhul A.; Essam, Daryl L.; Deb, Kalyanmoy; Elsayed, Saber M.

    2014-11-01

    Constraint handling is an important aspect of evolutionary constrained optimization. Currently, the mechanism used for constraint handling with evolutionary algorithms mainly assists the selection process, but not the actual search process. In this article, first a genetic algorithm is combined with a class of search methods, known as constraint consensus methods, that assist infeasible individuals to move towards the feasible region. This approach is also integrated with a memetic algorithm. The proposed algorithm is tested and analysed by solving two sets of standard benchmark problems, and the results are compared with other state-of-the-art algorithms. The comparisons show that the proposed algorithm outperforms other similar algorithms. The algorithm has also been applied to solve a practical economic load dispatch problem, where it also shows superior performance over other algorithms.

  6. Weighted constraints in generative linguistics.

    PubMed

    Pater, Joe

    2009-08-01

    Harmonic Grammar (HG) and Optimality Theory (OT) are closely related formal frameworks for the study of language. In both, the structure of a given language is determined by the relative strengths of a set of constraints. They differ in how these strengths are represented: as numerical weights (HG) or as ranks (OT). Weighted constraints have advantages for the construction of accounts of language learning and other cognitive processes, partly because they allow for the adaptation of connectionist and statistical models. HG has been little studied in generative linguistics, however, largely due to influential claims that weighted constraints make incorrect predictions about the typology of natural languages, predictions that are not shared by the more popular OT. This paper makes the case that HG is in fact a promising framework for typological research, and reviews and extends the existing arguments for weighted over ranked constraints.

  7. Fluid convection, constraint and causation

    PubMed Central

    Bishop, Robert C.

    2012-01-01

    Complexity—nonlinear dynamics for my purposes in this essay—is rich with metaphysical and epistemological implications but is receiving sustained philosophical analysis only recently. I will explore some of the subtleties of causation and constraint in Rayleigh–Bénard convection as an example of a complex phenomenon, and extract some lessons for further philosophical reflection on top-down constraint and causation particularly with respect to causal foundationalism. PMID:23386955

  8. Domestication changes innate constraints for birdsong learning.

    PubMed

    Kagawa, Hiroko; Suzuki, Kenta; Takahasi, Miki; Okanoya, Kazuo

    2014-07-01

    Birdsongs are acquired by imitating the sounds produced by conspecifics. Within a species, songs diverge by cultural transmission, but the range of species-specific features is restricted by innate constraints. Bengalese finches (Lonchura striata var. domestica) are a domesticated strain of the wild White-rumped munia (Lonchura striata). The songs of the domesticated strain have more tonal sounds and more variable sequences than those of the wild strain. We compared the features of songs that were produced by normal birds, isolation-reared birds, and cross-fostered birds in both White-rumped munias and Bengalese finches to identify differences in the genetic and environmental factors of their songs. Factor analyses were conducted based on 17 song measurements. We found that isolated songs differed from normal and cross-fostered songs, especially in unstable prosodic features. In addition, there were significant differences in sound property of mean frequency between the two strains regardless of the rearing conditions. Thus, innate constraints that partially determine birdsong phenotypes may be altered through domestication.

  9. Domestication changes innate constraints for birdsong learning.

    PubMed

    Kagawa, Hiroko; Suzuki, Kenta; Takahasi, Miki; Okanoya, Kazuo

    2014-07-01

    Birdsongs are acquired by imitating the sounds produced by conspecifics. Within a species, songs diverge by cultural transmission, but the range of species-specific features is restricted by innate constraints. Bengalese finches (Lonchura striata var. domestica) are a domesticated strain of the wild White-rumped munia (Lonchura striata). The songs of the domesticated strain have more tonal sounds and more variable sequences than those of the wild strain. We compared the features of songs that were produced by normal birds, isolation-reared birds, and cross-fostered birds in both White-rumped munias and Bengalese finches to identify differences in the genetic and environmental factors of their songs. Factor analyses were conducted based on 17 song measurements. We found that isolated songs differed from normal and cross-fostered songs, especially in unstable prosodic features. In addition, there were significant differences in sound property of mean frequency between the two strains regardless of the rearing conditions. Thus, innate constraints that partially determine birdsong phenotypes may be altered through domestication. PMID:24793499

  10. Genetic and Rare Diseases Information Center

    MedlinePlus

    ... and Students guides/pages/99/teachers-and-students Teaching Resources News 1 In The Spotlight News Archive ... about rare or genetic diseases in English or Spanish. text go Browse Diseases View diseases by alphabetical ...

  11. Genetics Home Reference: isolated Pierre Robin sequence

    MedlinePlus

    ... of isolated Pierre Robin sequence: Boston Children's Hospital: Cleft Lip and Cleft Palate Treatment and Care Genetic Testing ... 7 links) Centers for Disease Control: Facts About Cleft Lip and Cleft Palate Children's Craniofacial Association: A Guide ...

  12. Medical genetics

    SciTech Connect

    Jorde, L.B.; Carey, J.C.; White, R.L.

    1995-10-01

    This book on the subject of medical genetics is a textbook aimed at a very broad audience: principally, medical students, nursing students, graduate, and undergraduate students. The book is actually a primer of general genetics as applied to humans and provides a well-balanced introduction to the scientific and clinical basis of human genetics. The twelve chapters include: Introduction, Basic Cell Biology, Genetic Variation, Autosomal Dominant and Recessive Inheritance, Sex-linked and Mitochondrial Inheritance, Clinical Cytogenetics, Gene Mapping, Immunogenetics, Cancer Genetics, Multifactorial Inheritance and Common Disease, Genetic Screening, Genetic Diagnosis and Gene Therapy, and Clinical Genetics and Genetic Counseling.

  13. Genetic algorithms

    NASA Technical Reports Server (NTRS)

    Wang, Lui; Bayer, Steven E.

    1991-01-01

    Genetic algorithms are mathematical, highly parallel, adaptive search procedures (i.e., problem solving methods) based loosely on the processes of natural genetics and Darwinian survival of the fittest. Basic genetic algorithms concepts are introduced, genetic algorithm applications are introduced, and results are presented from a project to develop a software tool that will enable the widespread use of genetic algorithm technology.

  14. Generating properly weighted ensemble of conformations of proteins from sparse or indirect distance constraints.

    PubMed

    Lin, Ming; Lu, Hsiao-Mei; Chen, Rong; Liang, Jie

    2008-09-01

    Inferring three-dimensional structural information of biomacromolecules such as proteins from limited experimental data is an important and challenging task. Nuclear Overhauser effect measurements based on nucleic magnetic resonance, disulfide linking, and electron paramagnetic resonance labeling studies can all provide useful partial distance constraint characteristic of the conformations of proteins. In this study, we describe a general approach for reconstructing conformations of biomolecules that are consistent with given distance constraints. Such constraints can be in the form of upper bounds and lower bounds of distances between residue pairs, contact maps based on specific contact distance cutoff values, or indirect distance constraints such as experimental phi-value measurement. Our approach is based on the framework of sequential Monte Carlo method, a chain growth-based method. We have developed a novel growth potential function to guide the generation of conformations that satisfy given distance constraints. This potential function incorporates not only the distance information of current residue during growth but also the distance information of future residues by introducing global distance upper bounds between residue pairs and the placement of reference points. To obtain protein conformations from indirect distance constraints in the form of experimental phi-values, we first generate properly weighted contact maps satisfying phi-value constraints, we then generate conformations from these contact maps. We show that our approach can faithfully generate conformations that satisfy the given constraints, which approach the native structures when distance constraints for all residue pairs are given.

  15. COATING ALTERNATIVES GUIDE (CAGE) USER'S GUIDE

    EPA Science Inventory

    The guide provides instructions for using the Coating Alternatives GuidE (CAGE) software program, version 1.0. It assumes that the user is familiar with the fundamentals of operating an IBM-compatible personal computer (PC) under the Microsoft disk operating system (MS-DOS). CAGE...

  16. Canali-type channels on Venus - Some genetic constraints

    NASA Technical Reports Server (NTRS)

    Komatsu, Goro; Kargel, Jeffrey S.; Baker, Victor R.

    1992-01-01

    Canali-type channels on Venus are unique because of their great lengths (up to 6800 km) and nearly constant channel cross sectional shapes along their paths. A simple model incorporating channel flow and radiative cooling suggests that common terrestrial-type tholeiite lava cannot sustain a superheated and turbulent state for the long distances required for thermal erosion of canali within allowable discharge rates. If canali formed mainly by constructional processes, laminar tholeiitic flow of relatively high, sustained discharge rates might travel the observed distances, but the absence of levees would need to be explained. An exotic low temperature, low viscosity lava like carbonatite or sulfur seems to be required for the erosional genesis of canali.

  17. New Genetics

    MedlinePlus

    ... human genome, behavioral genetics, pharmacogenetics, drug resistance, biofilms, computer modeling. » more Chapter 5: 21st-Century Genetics Covers systems biology, GFP, genetic testing, privacy concerns, DNA forensics, ...

  18. Genetic Counseling

    MedlinePlus

    Genetic counseling provides information and support to people who have, or may be at risk for, genetic disorders. A ... meets with you to discuss genetic risks. The counseling may be for yourself or a family member. ...

  19. Genetic Counseling

    MedlinePlus

    ... Articles Genetic Counseling Information For... Media Policy Makers Genetic Counseling Language: English Español (Spanish) Recommend on Facebook ... informed decisions about testing and treatment. Reasons for Genetic Counseling There are many reasons that people go ...

  20. Developmental constraints on behavioural flexibility

    PubMed Central

    Holekamp, Kay E.; Swanson, Eli M.; Van Meter, Page E.

    2013-01-01

    We suggest that variation in mammalian behavioural flexibility not accounted for by current socioecological models may be explained in part by developmental constraints. From our own work, we provide examples of constraints affecting variation in behavioural flexibility, not only among individuals, but also among species and higher taxonomic units. We first implicate organizational maternal effects of androgens in shaping individual differences in aggressive behaviour emitted by female spotted hyaenas throughout the lifespan. We then compare carnivores and primates with respect to their locomotor and craniofacial adaptations. We inquire whether antagonistic selection pressures on the skull might impose differential functional constraints on evolvability of skulls and brains in these two orders, thus ultimately affecting behavioural flexibility in each group. We suggest that, even when carnivores and primates would theoretically benefit from the same adaptations with respect to behavioural flexibility, carnivores may nevertheless exhibit less behavioural flexibility than primates because of constraints imposed by past adaptations in the morphology of the limbs and skull. Phylogenetic analysis consistent with this idea suggests greater evolutionary lability in relative brain size within families of primates than carnivores. Thus, consideration of developmental constraints may help elucidate variation in mammalian behavioural flexibility. PMID:23569298

  1. Developmental constraints on behavioural flexibility.

    PubMed

    Holekamp, Kay E; Swanson, Eli M; Van Meter, Page E

    2013-05-19

    We suggest that variation in mammalian behavioural flexibility not accounted for by current socioecological models may be explained in part by developmental constraints. From our own work, we provide examples of constraints affecting variation in behavioural flexibility, not only among individuals, but also among species and higher taxonomic units. We first implicate organizational maternal effects of androgens in shaping individual differences in aggressive behaviour emitted by female spotted hyaenas throughout the lifespan. We then compare carnivores and primates with respect to their locomotor and craniofacial adaptations. We inquire whether antagonistic selection pressures on the skull might impose differential functional constraints on evolvability of skulls and brains in these two orders, thus ultimately affecting behavioural flexibility in each group. We suggest that, even when carnivores and primates would theoretically benefit from the same adaptations with respect to behavioural flexibility, carnivores may nevertheless exhibit less behavioural flexibility than primates because of constraints imposed by past adaptations in the morphology of the limbs and skull. Phylogenetic analysis consistent with this idea suggests greater evolutionary lability in relative brain size within families of primates than carnivores. Thus, consideration of developmental constraints may help elucidate variation in mammalian behavioural flexibility. PMID:23569298

  2. Developmental constraints on behavioural flexibility.

    PubMed

    Holekamp, Kay E; Swanson, Eli M; Van Meter, Page E

    2013-05-19

    We suggest that variation in mammalian behavioural flexibility not accounted for by current socioecological models may be explained in part by developmental constraints. From our own work, we provide examples of constraints affecting variation in behavioural flexibility, not only among individuals, but also among species and higher taxonomic units. We first implicate organizational maternal effects of androgens in shaping individual differences in aggressive behaviour emitted by female spotted hyaenas throughout the lifespan. We then compare carnivores and primates with respect to their locomotor and craniofacial adaptations. We inquire whether antagonistic selection pressures on the skull might impose differential functional constraints on evolvability of skulls and brains in these two orders, thus ultimately affecting behavioural flexibility in each group. We suggest that, even when carnivores and primates would theoretically benefit from the same adaptations with respect to behavioural flexibility, carnivores may nevertheless exhibit less behavioural flexibility than primates because of constraints imposed by past adaptations in the morphology of the limbs and skull. Phylogenetic analysis consistent with this idea suggests greater evolutionary lability in relative brain size within families of primates than carnivores. Thus, consideration of developmental constraints may help elucidate variation in mammalian behavioural flexibility.

  3. Data assimilation with inequality constraints

    NASA Astrophysics Data System (ADS)

    Thacker, W. C.

    If values of variables in a numerical model are limited to specified ranges, these restrictions should be enforced when data are assimilated. The simplest option is to assimilate without regard for constraints and then to correct any violations without worrying about additional corrections implied by correlated errors. This paper addresses the incorporation of inequality constraints into the standard variational framework of optimal interpolation with emphasis on our limited knowledge of the underlying probability distributions. Simple examples involving only two or three variables are used to illustrate graphically how active constraints can be treated as error-free data when background errors obey a truncated multi-normal distribution. Using Lagrange multipliers, the formalism is expanded to encompass the active constraints. Two algorithms are presented, both relying on a solution ignoring the inequality constraints to discover violations to be enforced. While explicitly enforcing a subset can, via correlations, correct the others, pragmatism based on our poor knowledge of the underlying probability distributions suggests the expedient of enforcing them all explicitly to avoid the computationally expensive task of determining the minimum active set. If additional violations are encountered with these solutions, the process can be repeated. Simple examples are used to illustrate the algorithms and to examine the nature of the corrections implied by correlated errors.

  4. Genetic Dissection of Neural Circuits

    PubMed Central

    Luo, Liqun; Callaway, Edward M.; Svoboda, Karel

    2009-01-01

    Understanding the principles of information processing in neural circuits requires systematic characterization of the participating cell types and their connections, and the ability to measure and perturb their activity. Genetic approaches promise to bring experimental access to complex neural systems, including genetic stalwarts such as the fly and mouse, but also to nongenetic systems such as primates. Together with anatomical and physiological methods, cell-type-specific expression of protein markers and sensors and transducers will be critical to construct circuit diagrams and to measure the activity of genetically defined neurons. Inactivation and activation of genetically defined cell types will establish causal relationships between activity in specific groups of neurons, circuit function, and animal behavior. Genetic analysis thus promises to reveal the logic of the neural circuits in complex brains that guide behaviors. Here we review progress in the genetic analysis of neural circuits and discuss directions for future research and development. PMID:18341986

  5. Mice and Men Environmental Balance, Parts Three and Four of an Integrated Science Sequence, Teacher's Guide, 1970 Edition.

    ERIC Educational Resources Information Center

    Portland Project Committee, OR.

    This teacher's guide contains parts three and four of the four-part first year Portland Project, a three-year secondary integrated science curriculum sequence. Part three of the guide deals with topics such as the cell, reproduction, embryology, genetics, genetic diseases, genetics and change, populations, effects of density on populations,…

  6. Symmetry constraint for foreground extraction.

    PubMed

    Fu, Huazhu; Cao, Xiaochun; Tu, Zhuowen; Lin, Dongdai

    2014-05-01

    Symmetry as an intrinsic shape property is often observed in natural objects. In this paper, we discuss how explicitly taking into account the symmetry constraint can enhance the quality of foreground object extraction. In our method, a symmetry foreground map is used to represent the symmetry structure of the image, which includes the symmetry matching magnitude and the foreground location prior. Then, the symmetry constraint model is built by introducing this symmetry structure into the graph-based segmentation function. Finally, the segmentation result is obtained via graph cuts. Our method encourages objects with symmetric parts to be consistently extracted. Moreover, our symmetry constraint model is applicable to weak symmetric objects under the part-based framework. Quantitative and qualitative experimental results on benchmark datasets demonstrate the advantages of our approach in extracting the foreground. Our method also shows improved results in segmenting objects with weak, complex symmetry properties.

  7. Magnetotail dynamics under isobaric constraints

    NASA Technical Reports Server (NTRS)

    Birn, Joachim; Schindler, Karl; Janicke, Lutz; Hesse, Michael

    1994-01-01

    Using linear theory and nonlinear MHD simulations, we investigate the resistive and ideal MHD stability of two-dimensional plasma configurations under the isobaric constraint dP/dt = 0, which in ideal MHD is equivalent to conserving the pressure function P = P(A), where A denotes the magnetic flux. This constraint is satisfied for incompressible modes, such as Alfven waves, and for systems undergoing energy losses. The linear stability analysis leads to a Schroedinger equation, which can be investigated by standard quantum mechanics procedures. We present an application to a typical stretched magnetotail configuration. For a one-dimensional sheet equilibrium characteristic properties of tearing instability are rediscovered. However, the maximum growth rate scales with the 1/7 power of the resistivity, which implies much faster growth than for the standard tearing mode (assuming that the resistivity is small). The same basic eigen-mode is found also for weakly two-dimensional equilibria, even in the ideal MHD limit. In this case the growth rate scales with the 1/4 power of the normal magnetic field. The results of the linear stability analysis are confirmed qualitatively by nonlinear dynamic MHD simulations. These results suggest the interesting possibility that substorm onset, or the thinning in the late growth phase, is caused by the release of a thermodynamic constraint without the (immediate) necessity of releasing the ideal MHD constraint. In the nonlinear regime the resistive and ideal developments differ in that the ideal mode does not lead to neutral line formation without the further release of the ideal MHD constraint; instead a thin current sheet forms. The isobaric constraint is critically discussed. Under perhaps more realistic adiabatic conditions the ideal mode appears to be stable but could be driven by external perturbations and thus generate the thin current sheet in the late growth phase, before a nonideal instability sets in.

  8. The constraint model of attrition

    SciTech Connect

    Hartley, D.S. III.

    1989-01-01

    Helmbold demonstrated a relationship between a ratio containing initial force sizes and casualties, herein called the Helmbold ratio, and the initial force ratio in a large number of historical battles. This paper examines some of the complexity of the Helmbold ratio using analytical and simulation techniques and demonstrates that a constraint model of attrition captures some aspects of historical data. The effect that the constraint model would have on warfare modeling is uncertain. However, some speculation has been attempted concerning its use in large scale simulations. 9 refs., 7 figs., 2 tabs.

  9. Greenstone belt tectonics: Thermal constraints

    NASA Technical Reports Server (NTRS)

    Bickle, M. J.; Nisbet, E. G.

    1986-01-01

    Archaean rocks provide a record of the early stages of planetary evolution. The interpretation is frustrated by the probable unrepresentative nature of the preserved crust and by the well known ambiguities of tectonic geological synthesis. Broad constraints can be placed on the tectonic processes in the early Earth from global scale modeling of thermal and chemical evolution of the Earth and its hydrosphere and atmosphere. The Archean record is the main test of such models. Available general model constraints are outlined based on the global tectonic setting within which Archaean crust evolved and on the direct evidence the Archaean record provides, particularly the thermal state of the early Earth.

  10. Constraints on the evolution of function-valued traits: a study of growth in Tribolium castaneum.

    PubMed

    Irwin, K K; Carter, P A

    2013-12-01

    Growth trajectories often impact individual fitness. They are continuous by nature and so are amenable to analysis using a function-valued (FV) trait framework to reveal their underlying genetic architecture. Previous studies have found high levels of standing additive genetic (co)variance for growth trajectories despite the expectation that growth should be responding to frequent strong directional selection. In this study, the FV framework is used to estimate the additive genetic covariance function for growth trajectories in larval Tribolium castaneum to address questions about standing additive genetic (co)variance and possible evolutionary constraints on growth and to predict responses to four plausible selection regimes. Results show that additive genetic (co)variance is high at the early ages, but decreases towards later ages in the larval period. A selection gradient function of the same size and in the same direction of the first eigenfunction of the G-function should give the maximal response. However, evolutionary constraints may be acting to keep this maximal response from being realized, through either conflicting effects on survivability and fecundity of larger body size, few evolutionary directions having sufficient additive variance for a response, genetic trade-offs with other traits or physiological regulatory mechanisms. More light may be shed on these constraints through the development of more sophisticated statistical approaches and implementation of additional empirical studies to explicitly test for specific types of constraints.

  11. Contextual Constraints on Adolescents' Leisure.

    ERIC Educational Resources Information Center

    Silbereisen, Rainer K.

    2003-01-01

    Interlinks crucial cultural themes emerging from preceding chapters, highlighting the contextual constraints in adolescents' use of free time. Draws parallels across the nations discussed on issues related to how school molds leisure time, the balance of passive versus active leisure, timing of leisure pursuits, and the cumulative effect of…

  12. Perceptual Constraints in Phonotactic Learning

    ERIC Educational Resources Information Center

    Endress, Ansgar D.; Mehler, Jacques

    2010-01-01

    Structural regularities in language have often been attributed to symbolic or statistical general purpose computations, whereas perceptual factors influencing such generalizations have received less interest. Here, we use phonotactic-like constraints as a case study to ask whether the structural properties of specific perceptual and memory…

  13. Temporal Constraint Reasoning With Preferences

    NASA Technical Reports Server (NTRS)

    Khatib, Lina; Morris, Paul; Morris, Robert; Rossi, Francesca

    2001-01-01

    A number of reasoning problems involving the manipulation of temporal information can naturally be viewed as implicitly inducing an ordering of potential local decisions involving time (specifically, associated with durations or orderings of events) on the basis of preferences. For example. a pair of events might be constrained to occur in a certain order, and, in addition. it might be preferable that the delay between them be as large, or as small, as possible. This paper explores problems in which a set of temporal constraints is specified, where each constraint is associated with preference criteria for making local decisions about the events involved in the constraint, and a reasoner must infer a complete solution to the problem such that, to the extent possible, these local preferences are met in the best way. A constraint framework for reasoning about time is generalized to allow for preferences over event distances and durations, and we study the complexity of solving problems in the resulting formalism. It is shown that while in general such problems are NP-hard, some restrictions on the shape of the preference functions, and on the structure of the preference set, can be enforced to achieve tractability. In these cases, a simple generalization of a single-source shortest path algorithm can be used to compute a globally preferred solution in polynomial time.

  14. Constraints on galaxy formation theories

    NASA Technical Reports Server (NTRS)

    Szalay, A. S.

    1986-01-01

    The present theories of galaxy formation are reviewed. The relation between peculiar velocities, temperature fluctuations of the microwave background and the correlation function of galaxies point to the possibility that galaxies do not form uniformly everywhere. The velocity data provide strong constraints on the theories even in the case when light does not follow mass of the universe.

  15. Institutional constraints on alternative water for energy: a guidebook for regional assessments

    SciTech Connect

    Not Available

    1980-11-01

    Basic information is presented about the legal, political, and social constraints faced by energy developers in the acquisition of water from underground, irrigation return flow, municipal waste, and saline sources. It is a guide to those institutional constraints which are general and pronounced enough to be important for regional assessments. First, attention was focused on the acquisition phase of the water use cycle. Second, constraints were analyzed primarily from a regional, rather than state-by-state, perspective. Emphasis was placed generally on the West - particularly the synfuel-rich Rocky Mountain states, the East, and Mid-West, in that order. Alaska and Hawaii were not surveyed. Third, the study focuses on the constraints associated with groundwater, municipal waste, irrigation return flow, and sea water, in that order. The phrase, institutional constraints, as used in the study, means legal, social, economic, and political restrictions, requirements, circumstances, or conditions that must be anticipated or responded to in order to acquire water for energy development. The study focuses primarily on legal constraints and secondarily on political constraints, because they tend to encompass or reflect other forms of institutional constraints.

  16. Design constraints of the LST fine guidance sensor

    NASA Technical Reports Server (NTRS)

    Wissinger, A. B.

    1975-01-01

    The LST Fine Guidance Sensor design is shaped by the rate of occurrence of suitable guide stars, the competition for telescope focal plane space with the Science Instruments, and the sensitivity of candidate image motion sensors. The relationship between these parameters is presented, and sensitivity to faint stars is shown to be of prime importance. An interferometric technique of image motion sensing is shown to have improved sensitivity and, therefore, a reduced focal plane area requirement in comparison with other candidate techniques (image-splitting prism and image dissector tube techniques). Another design requirement is speed in acquiring the guide star in order to maximize the time available for science observations. The design constraints are shown parametrically, and modelling results are presented.

  17. User's guide for SOL/QPSOL: a Fortran package for quadratic programming

    SciTech Connect

    Gill, P.E.; Murray, W.; Saunders, M.A.; Wright, M.H.

    1983-07-01

    This report forms the user's guide for Version 3.1 of SOL/QPSOL, a set of Fortran subroutines designed to locate the minimum value of an arbitrary quadratic function subject to linear constraints and simple upper and lower bounds. If the quadratic function is convex, a global minimum is found; otherwise, a local minimum is found. The method used is most efficient when many constraints or bounds are active at the solution. QPSOL treats the Hessian and general constraints as dense matrices, and hence is not intended for large sparse problems. This document replaces the previous user's guide of June 1982.

  18. Stress constraints in optimality criteria design

    NASA Technical Reports Server (NTRS)

    Levy, R.

    1982-01-01

    Procedures described emphasize the processing of stress constraints within optimality criteria designs for low structural weight with stress and compliance constraints. Prescreening criteria are used to partition stress constraints into either potentially active primary sets or passive secondary sets that require minimal processing. Side constraint boundaries for passive constraints are derived by projections from design histories to modify conventional stress-ratio boundaries. Other procedures described apply partial structural modification reanalysis to design variable groups to correct stress constraint violations of unfeasible designs. Sample problem results show effective design convergence and, in particular, advantages for reanalysis in obtaining lower feasible design weights.

  19. Evaluating the role of reproductive constraints in ant social evolution.

    PubMed

    Khila, Abderrahman; Abouheif, Ehab

    2010-02-27

    The reproductive division of labour is a key feature of eusociality in ants, where queen and worker castes show dramatic differences in the development of their reproductive organs. To understand the developmental and genetic basis underlying this division of labour, we performed a molecular analysis of ovary function and germ cell development in queens and workers. We show that the processes of ovarian development in queens have been highly conserved relative to the fruitfly Drosophila melanogaster. We also identify specific steps during oogenesis and embryogenesis in which ovarian and germ cell development have been evolutionarily modified in the workers. These modifications, which we call 'reproductive constraints', are often assumed to represent neutral degenerations that are a consequence of social evolutionary forces. Based on our developmental and functional analysis of these constraints, however, we propose and discuss the alternative hypothesis that reproductive constraints represent adaptive proximate mechanisms or traits for maintaining social harmony in ants. We apply a multi-level selection framework to help understand the role of these constraints in ant social evolution. A complete understanding of how cooperation, conflict and developmental systems evolve in social groups requires a 'socio-evo-devo' approach that integrates social evolutionary and developmental biology.

  20. Evolutionary constraints and the maintenance of individual specialization throughout succession.

    PubMed

    Monro, Keyne; Marshall, Dustin J

    2013-12-01

    Constraints on life-history traits, with their close links to fitness, are widely invoked as limits to niche expansion at most organizational levels. Theoretically, such constraints can maintain individual specialization by preventing adaptation to all niches available, but empirical evidence of them remains elusive for natural populations. This problem may be compounded by a tendency to seek constraints involving multiple traits, neglecting their added potential to manifest in trait expression across environments (i.e., within reaction norms). By replicating genotypes of a colonial marine invertebrate across successional stages in its local community, and taking a holistic approach to the analysis of ensuing reaction norms for fitness, we show the potential for individual specialization to be maintained by genetic constraints associated with these norms, which limit the potential for fitness at one successional stage to improve without loss of fitness at others. Our study provides new insight into the evolutionary maintenance of individual specialization in natural populations and reinforces the importance of reaction norms for studying this phenomenon.

  1. Evolutionary constraints and the maintenance of individual specialization throughout succession.

    PubMed

    Monro, Keyne; Marshall, Dustin J

    2013-12-01

    Constraints on life-history traits, with their close links to fitness, are widely invoked as limits to niche expansion at most organizational levels. Theoretically, such constraints can maintain individual specialization by preventing adaptation to all niches available, but empirical evidence of them remains elusive for natural populations. This problem may be compounded by a tendency to seek constraints involving multiple traits, neglecting their added potential to manifest in trait expression across environments (i.e., within reaction norms). By replicating genotypes of a colonial marine invertebrate across successional stages in its local community, and taking a holistic approach to the analysis of ensuing reaction norms for fitness, we show the potential for individual specialization to be maintained by genetic constraints associated with these norms, which limit the potential for fitness at one successional stage to improve without loss of fitness at others. Our study provides new insight into the evolutionary maintenance of individual specialization in natural populations and reinforces the importance of reaction norms for studying this phenomenon. PMID:24299414

  2. Cancer genetics in primary care.

    PubMed

    McKelvey, Kent D; Evans, James P

    2003-11-01

    Primary care physicians are in a unique position to apply recent advances in cancer genetics to the improved care of their patients. Although the impact of our burgeoning knowledge in this area is significant and growing, it is often incompletely understood by the general practitioner. In this article we review the genetic basis of cancer and focus attention on inherited forms of cancer using breast cancer gene 1 (BRCA1) and breast cancer gene 2 (BRCA2) as examples. Specific attributes of family and personal history are the most significant indicators of an increased risk of cancer in the individual patient. Genetic testing can be used to further assess risk and guide strategies for cancer screening, prevention, and treatment. However, the decision of whether to pursue genetic testing and the interpretation of results are complex. We review factors involved in these decisions as well as the implications, risks, and benefits of genetic testing for the individual and the family.

  3. Genetic disorders producing compressive radiculopathy.

    PubMed

    Corey, Joseph M

    2006-11-01

    Back pain is a frequent complaint seen in neurological practice. In evaluating back pain, neurologists are asked to evaluate patients for radiculopathy, determine whether they may benefit from surgery, and help guide management. Although disc herniation is the most common etiology of compressive radiculopathy, there are many other causes, including genetic disorders. This article is a discussion of genetic disorders that cause or contribute to radiculopathies. These genetic disorders include neurofibromatosis, Paget's disease of bone, and ankylosing spondylitis. Numerous genetic disorders can also lead to deformities of the spine, including spinal muscular atrophy, Friedreich's ataxia, Charcot-Marie-Tooth disease, familial dysautonomia, idiopathic torsional dystonia, Marfan's syndrome, and Ehlers-Danlos syndrome. However, the extent of radiculopathy caused by spine deformities is essentially absent from the literature. Finally, recent investigation into the heritability of disc degeneration and lumbar disc herniation suggests a significant genetic component in the etiology of lumbar disc disease. PMID:17048153

  4. Genetic disorders producing compressive radiculopathy.

    PubMed

    Corey, Joseph M

    2006-11-01

    Back pain is a frequent complaint seen in neurological practice. In evaluating back pain, neurologists are asked to evaluate patients for radiculopathy, determine whether they may benefit from surgery, and help guide management. Although disc herniation is the most common etiology of compressive radiculopathy, there are many other causes, including genetic disorders. This article is a discussion of genetic disorders that cause or contribute to radiculopathies. These genetic disorders include neurofibromatosis, Paget's disease of bone, and ankylosing spondylitis. Numerous genetic disorders can also lead to deformities of the spine, including spinal muscular atrophy, Friedreich's ataxia, Charcot-Marie-Tooth disease, familial dysautonomia, idiopathic torsional dystonia, Marfan's syndrome, and Ehlers-Danlos syndrome. However, the extent of radiculopathy caused by spine deformities is essentially absent from the literature. Finally, recent investigation into the heritability of disc degeneration and lumbar disc herniation suggests a significant genetic component in the etiology of lumbar disc disease.

  5. Unitarity constraints on trimaximal mixing

    SciTech Connect

    Kumar, Sanjeev

    2010-07-01

    When the neutrino mass eigenstate {nu}{sub 2} is trimaximally mixed, the mixing matrix is called trimaximal. The middle column of the trimaximal mixing matrix is identical to tribimaximal mixing and the other two columns are subject to unitarity constraints. This corresponds to a mixing matrix with four independent parameters in the most general case. Apart from the two Majorana phases, the mixing matrix has only one free parameter in the CP conserving limit. Trimaximality results in interesting interplay between mixing angles and CP violation. A notion of maximal CP violation naturally emerges here: CP violation is maximal for maximal 2-3 mixing. Similarly, there is a natural constraint on the deviation from maximal 2-3 mixing which takes its maximal value in the CP conserving limit.

  6. Traj_opt User's Guide

    NASA Technical Reports Server (NTRS)

    Saunders, David A.

    2005-01-01

    Trajectory optimization program Traj_opt was developed at Ames Research Center to help assess the potential benefits of ultrahigh temperature ceramic materials applied to reusable space vehicles with sharp noses and wing leading edges. Traj_opt loosely couples the Ames three-degrees-of-freedom trajectory package Traj (see NASA-TM-2004-212847) with the SNOPT optimization package (Stanford University Technical Report SOL 98-1). Traj_opt version January 22, 2003 is covered by this user guide. The program has been applied extensively to entry and ascent abort trajectory calculations for sharp and blunt crew transfer vehicles. The main optimization variables are control points for the angle of attack and bank angle time histories. No propulsion options are provided, but numerous objective functions may be specified and the nonlinear constraints implemented include a distributed surface heating constraint capability. Aero-capture calculations are also treated with an option to minimize orbital eccentricity at apoapsis. Traj_opt runs efficiently on a single processor, using forward or central differences for the gradient calculations. Results may be displayed conveniently with Gnuplot scripts. Control files recommended for five standard reentry and ascent abort trajectories are included along with detailed descriptions of the inputs and outputs.

  7. Managing Restaurant Tables using Constraints

    NASA Astrophysics Data System (ADS)

    Vidotto, Alfio; Brown, Kenneth N.; Beck, J. Christopher

    Restaurant table management can have significant impact on both profitability and the customer experience. The core of the issue is a complex dynamic combinatorial problem. We show how to model the problem as constraint satisfaction, with extensions which generate flexible seating plans and which maintain stability when changes occur. We describe an implemented system which provides advice to users in real time. The system is currently being evaluated in a restaurant environment.

  8. Macroscopic constraints on string unification

    SciTech Connect

    Taylor, T.R.

    1989-03-01

    The comparison of sting theory with experiment requires a huge extrapolation from the microscopic distances, of order of the Planck length, up to the macroscopic laboratory distances. The quantum effects give rise to large corrections to the macroscopic predictions of sting unification. I discus the model-independent constraints on the gravitational sector of string theory due to the inevitable existence of universal Fradkin-Tseytlin dilatons. 9 refs.

  9. Updating neutrino magnetic moment constraints

    NASA Astrophysics Data System (ADS)

    Cañas, B. C.; Miranda, O. G.; Parada, A.; Tórtola, M.; Valle, J. W. F.

    2016-02-01

    In this paper we provide an updated analysis of the neutrino magnetic moments (NMMs), discussing both the constraints on the magnitudes of the three transition moments Λi and the role of the CP violating phases present both in the mixing matrix and in the NMM matrix. The scattering of solar neutrinos off electrons in Borexino provides the most stringent restrictions, due to its robust statistics and the low energies observed, below 1 MeV. Our new limit on the effective neutrino magnetic moment which follows from the most recent Borexino data is 3.1 ×10-11μB at 90% C.L. This corresponds to the individual transition magnetic moment constraints: |Λ1 | ≤ 5.6 ×10-11μB, |Λ2 | ≤ 4.0 ×10-11μB, and |Λ3 | ≤ 3.1 ×10-11μB (90% C.L.), irrespective of any complex phase. Indeed, the incoherent admixture of neutrino mass eigenstates present in the solar flux makes Borexino insensitive to the Majorana phases present in the NMM matrix. For this reason we also provide a global analysis including the case of reactor and accelerator neutrino sources, presenting the resulting constraints for different values of the relevant CP phases. Improved reactor and accelerator neutrino experiments will be needed in order to underpin the full profile of the neutrino electromagnetic properties.

  10. Infrared Constraint on Ultraviolet Theories

    SciTech Connect

    Tsai, Yuhsin

    2012-08-01

    While our current paradigm of particle physics, the Standard Model (SM), has been extremely successful at explaining experiments, it is theoretically incomplete and must be embedded into a larger framework. In this thesis, we review the main motivations for theories beyond the SM (BSM) and the ways such theories can be constrained using low energy physics. The hierarchy problem, neutrino mass and the existence of dark matter (DM) are the main reasons why the SM is incomplete . Two of the most plausible theories that may solve the hierarchy problem are the Randall-Sundrum (RS) models and supersymmetry (SUSY). RS models usually suffer from strong flavor constraints, while SUSY models produce extra degrees of freedom that need to be hidden from current experiments. To show the importance of infrared (IR) physics constraints, we discuss the flavor bounds on the anarchic RS model in both the lepton and quark sectors. For SUSY models, we discuss the difficulties in obtaining a phenomenologically allowed gaugino mass, its relation to R-symmetry breaking, and how to build a model that avoids this problem. For the neutrino mass problem, we discuss the idea of generating small neutrino masses using compositeness. By requiring successful leptogenesis and the existence of warm dark matter (WDM), we can set various constraints on the hidden composite sector. Finally, to give an example of model independent bounds from collider experiments, we show how to constrain the DM–SM particle interactions using collider results with an effective coupling description.

  11. Isocurvature constraints on portal couplings

    NASA Astrophysics Data System (ADS)

    Kainulainen, Kimmo; Nurmi, Sami; Tenkanen, Tommi; Tuominen, Kimmo; Vaskonen, Ville

    2016-06-01

    We consider portal models which are ultraweakly coupled with the Standard Model, and confront them with observational constraints on dark matter abundance and isocurvature perturbations. We assume the hidden sector to contain a real singlet scalar s and a sterile neutrino ψ coupled to s via a pseudoscalar Yukawa term. During inflation, a primordial condensate consisting of the singlet scalar s is generated, and its contribution to the isocurvature perturbations is imprinted onto the dark matter abundance. We compute the total dark matter abundance including the contributions from condensate decay and nonthermal production from the Standard Model sector. We then use the Planck limit on isocurvature perturbations to derive a novel constraint connecting dark matter mass and the singlet self coupling with the scale of inflation: mDM/GeV lesssim 0.2λs3/8 (H*/1011 GeV)‑3/2. This constraint is relevant in most portal models ultraweakly coupled with the Standard Model and containing light singlet scalar fields.

  12. Steric constraints as folding coadjuvant

    NASA Astrophysics Data System (ADS)

    Tarragó, M. E.; Rocha, Luiz F.; Dasilva, R. A.; Caliri, A.

    2003-03-01

    Through the analyses of the Miyazawa-Jernigan matrix it has been shown that the hydrophobic effect generates the dominant driving force for protein folding. By using both lattice and off-lattice models, it is shown that hydrophobic-type potentials are indeed efficient in inducing the chain through nativelike configurations, but they fail to provide sufficient stability so as to keep the chain in the native state. However, through comparative Monte Carlo simulations, it is shown that hydrophobic potentials and steric constraints are two basic ingredients for the folding process. Specifically, it is shown that suitable pairwise steric constraints introduce strong changes on the configurational activity, whose main consequence is a huge increase in the overall stability condition of the native state; detailed analysis of the effects of steric constraints on the heat capacity and configurational activity are provided. The present results support the view that the folding problem of globular proteins can be approached as a process in which the mechanism to reach the native conformation and the requirements for the globule stability are uncoupled.

  13. Constraint programming based biomarker optimization.

    PubMed

    Zhou, Manli; Luo, Youxi; Sun, Guoquan; Mai, Guoqin; Zhou, Fengfeng

    2015-01-01

    Efficient and intuitive characterization of biological big data is becoming a major challenge for modern bio-OMIC based scientists. Interactive visualization and exploration of big data is proven to be one of the successful solutions. Most of the existing feature selection algorithms do not allow the interactive inputs from users in the optimizing process of feature selection. This study investigates this question as fixing a few user-input features in the finally selected feature subset and formulates these user-input features as constraints for a programming model. The proposed algorithm, fsCoP (feature selection based on constrained programming), performs well similar to or much better than the existing feature selection algorithms, even with the constraints from both literature and the existing algorithms. An fsCoP biomarker may be intriguing for further wet lab validation, since it satisfies both the classification optimization function and the biomedical knowledge. fsCoP may also be used for the interactive exploration of bio-OMIC big data by interactively adding user-defined constraints for modeling.

  14. Constraints to commercialization of algal fuels.

    PubMed

    Chisti, Yusuf

    2013-09-10

    Production of algal crude oil has been achieved in various pilot scale facilities, but whether algal fuels can be produced in sufficient quantity to meaningfully displace petroleum fuels, has been largely overlooked. Limitations to commercialization of algal fuels need to be understood and addressed for any future commercialization. This review identifies the major constraints to commercialization of transport fuels from microalgae. Algae derived fuels are expensive compared to petroleum derived fuels, but this could change. Unfortunately, improved economics of production are not sufficient for an environmentally sustainable production, or its large scale feasibility. A low-cost point supply of concentrated carbon dioxide colocated with the other essential resources is necessary for producing algal fuels. An insufficiency of concentrated carbon dioxide is actually a major impediment to any substantial production of algal fuels. Sustainability of production requires the development of an ability to almost fully recycle the phosphorous and nitrogen nutrients that are necessary for algae culture. Development of a nitrogen biofixation ability to support production of algal fuels ought to be an important long term objective. At sufficiently large scale, a limited supply of freshwater will pose a significant limitation to production even if marine algae are used. Processes for recovering energy from the algal biomass left after the extraction of oil, are required for achieving a net positive energy balance in the algal fuel oil. The near term outlook for widespread use of algal fuels appears bleak, but fuels for niche applications such as in aviation may be likely in the medium term. Genetic and metabolic engineering of microalgae to boost production of fuel oil and ease its recovery, are essential for commercialization of algal fuels. Algae will need to be genetically modified for improved photosynthetic efficiency in the long term. PMID:23886651

  15. Genetic Mapping

    MedlinePlus

    ... Genetic Education Resources for Teachers Genomic Careers National DNA Day Online Education Kit Online Genetics Education Resources ... prevalent. Using various laboratory techniques, the scientists isolate DNA from these samples and examine it for unique ...

  16. Genetic Disorders

    MedlinePlus

    ... This can cause a medical condition called a genetic disorder. You can inherit a gene mutation from ... during your lifetime. There are three types of genetic disorders: Single-gene disorders, where a mutation affects ...

  17. A Hybrid Constraint Representation and Reasoning Framework

    NASA Technical Reports Server (NTRS)

    Golden, Keith; Pang, Wanlin

    2004-01-01

    In this paper, we introduce JNET, a novel constraint representation and reasoning framework that supports procedural constraints and constraint attachments, providing a flexible way of integrating the constraint system with a runtime software environment and improving its applicability. We describe how JNET is applied to a real-world problem - NASA's Earth-science data processing domain, and demonstrate how JNET can be extended, without any knowledge of how it is implemented, to meet the growing demands of real-world applications.

  18. Genetic modification and genetic determinism

    PubMed Central

    Resnik, David B; Vorhaus, Daniel B

    2006-01-01

    In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions. PMID:16800884

  19. Guide to Understanding Lymphedema

    MedlinePlus

    ... Diet, Nutrition and Exercise Expressive Writing Guided Imagery Hypnosis Massage Therapy Mindfulness-Based Stress Reduction Yoga and ... Diet, Nutrition and Exercise Expressive Writing Guided Imagery Hypnosis Massage Therapy Mindfulness-Based Stress Reduction Yoga and ...

  20. The genetics of dilated cardiomyopathy

    PubMed Central

    Dellefave, Lisa; McNally, Elizabeth M.

    2010-01-01

    Purpose of review More than forty different individual genes have been implicated in the inheritance of dilated cardiomyopathy. For a subset of these genes, mutations can lead to a spectrum of cardiomyopathy that extends to hypertrophic cardiomyopathy and left ventricular noncompaction. In nearly all cases, there is an increased risk of arrhythmias. With some genetic mutations, extracardiac manifestations are likely to be present. The precise genetic etiology can usually not be discerned from the cardiac and/or extracardiac manifestations and requires molecular genetic diagnosis for prognostic determination and cardiac care. Recent findings Newer technologies are influencing genetic testing, especially cardiomyopathy genetic testing, where an increased number of genes are now routinely being tested simultaneously. While this approach to testing multiple genes is increasing the diagnostic yield, the analysis of multiple genes in one test is also resulting in a large amount of genetic information of unclear significance. Summary Genetic testing is highly useful in the care of patients and families, since it guides diagnosis, influences care and aids in prognosis. However, the large amount of benign human genetic variation may complicate genetic results, and often requires a skilled team to accurately interpret the findings. PMID:20186049

  1. Learning and Parallelization Boost Constraint Search

    ERIC Educational Resources Information Center

    Yun, Xi

    2013-01-01

    Constraint satisfaction problems are a powerful way to abstract and represent academic and real-world problems from both artificial intelligence and operations research. A constraint satisfaction problem is typically addressed by a sequential constraint solver running on a single processor. Rather than construct a new, parallel solver, this work…

  2. Cultural and Social Constraints on Portability.

    ERIC Educational Resources Information Center

    Murray-Lasso, Marco

    1990-01-01

    Describes 12 constraints imposed by culture on educational software portability. Nielsen's seven-level virtual protocol model of human-computer interaction is discussed as a framework for considering the constraints, a hypothetical example of adapting software for Mexico is included, and suggestions for overcoming constraints and making software…

  3. Genetic principles.

    PubMed

    Abuelo, D

    1987-01-01

    The author discusses the basic principles of genetics, including the classification of genetic disorders and a consideration of the rules and mechanisms of inheritance. The most common pitfalls in clinical genetic diagnosis are described, with emphasis on the problem of the negative or misleading family history.

  4. Imaging Genetics

    ERIC Educational Resources Information Center

    Munoz, Karen E.; Hyde, Luke W.; Hariri, Ahmad R.

    2009-01-01

    Imaging genetics is an experimental strategy that integrates molecular genetics and neuroimaging technology to examine biological mechanisms that mediate differences in behavior and the risks for psychiatric disorder. The basic principles in imaging genetics and the development of the field are discussed.

  5. Genetic Testing

    MedlinePlus

    ... genetic tests for several reasons. These include Finding genetic diseases in unborn babies Finding out if people carry a gene for a disease and might pass it on to their children Screening embryos for disease Testing for genetic diseases in adults before they cause ...

  6. Swimming constraints and arm coordination.

    PubMed

    Seifert, Ludovic; Chollet, Didier; Rouard, Annie

    2007-02-01

    Following Newell's concept of constraint (1986), we sought to identify the constraints (organismic, environmental and task) on front crawl performance, focusing on arm coordination adaptations over increasing race paces. Forty-two swimmers (15 elite men, 15 mid-level men and 12 elite women) performed seven self-paced swim trials (race paces: as if competitively swimming 1500m, 800m, 400m, 200m, 100m, 50m, and maximal velocity, respectively) using the front crawl stroke. The paces were race simulations over 25m to avoid fatigue effects. Swim velocity, stroke rate, stroke length, and various arm stroke phases were calculated from video analysis. Arm coordination was quantified in terms of an index of coordination (IdC) based on the lag time between the propulsive phases of each arm. This measure quantified three possible coordination modes in the front crawl: opposition (continuity between the two arm propulsions), catch-up (a time gap between the two arm propulsions) and superposition (an overlap of the two arm propulsions). With increasing race paces, swim velocity, stroke rate, and stroke length, the three groups showed a similar transition in arm coordination mode at the critical 200m pace, which separated the long- and mid-pace pattern from the sprint pace pattern. The 200m pace was also characterized by a stroke rate close to 40strokemin(-1). The finding that all three groups showed a similar adaptation of arm coordination suggested that race paces, swim velocity, stroke rate and stroke length reflect task constraints that can be manipulated as control parameters, with race paces (R(2)=.28) and stroke rate (R(2)=.36) being the best predictors of IdC changes. On the other hand, only the elite men reached a velocity greater than 1.8ms(-1) and a stroke rate of 50strokemin(-1). They did so using superposition of the propulsion phases of the two arms, which occurred because of the great forward resistance created when these swimmers achieved high velocity, i.e., an

  7. Managerial Accounting. Study Guide.

    ERIC Educational Resources Information Center

    Plachta, Leonard E.

    This self-instructional study guide is part of the materials for a college-level programmed course in managerial accounting. The study guide is intended for use by students in conjuction with a separate textbook, Horngren's "Accounting for Management Control: An Introduction," and a workbook, Curry's "Student Guide to Accounting for Management…

  8. ESL VI Curriculum Guide.

    ERIC Educational Resources Information Center

    Flander, Leonard

    This curriculum guide for English as a Second Language (ESL) Level VI is the sixth of six in a Guam Community College ESL project series. The other five guides, a companion teacher's guide and pre- and post-tests are available separately (see note). The entire project centers around the Peabody Kits P, Level P, Level 1, Level 2, Level 3, and the…

  9. Optical mechanical analogy and nonlinear nonholonomic constraints

    NASA Astrophysics Data System (ADS)

    Bloch, Anthony M.; Rojo, Alberto G.

    2016-02-01

    In this paper we establish a connection between particle trajectories subject to a nonholonomic constraint and light ray trajectories in a variable index of refraction. In particular, we extend the analysis of systems with linear nonholonomic constraints to the dynamics of particles in a potential subject to nonlinear velocity constraints. We contrast the long time behavior of particles subject to a constant kinetic energy constraint (a thermostat) to particles with the constraint of parallel velocities. We show that, while in the former case the velocities of each particle equalize in the limit, in the latter case all the kinetic energies of each particle remain the same.

  10. Genetics Home Reference: cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy

    MedlinePlus

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions CADASIL cerebral autosomal dominant arteriopathy ...

  11. Trajectory constraints in qualitative simulation

    SciTech Connect

    Brajnik, G.; Clancy, D.J.

    1996-12-31

    We present a method for specifying temporal constraints on trajectories of dynamical systems and enforcing them during qualitative simulation. This capability can be used to focus a simulation, simulate non-autonomous and piecewise-continuous systems, reason about boundary condition problems and incorporate observations into the simulation. The method has been implemented in TeQSIM, a qualitative simulator that combines the expressive power of qualitative differential equations with temporal logic. It interleaves temporal logic model checking with the simulation to constrain and refine the resulting predicted behaviors and to inject discontinuous changes into the simulation.

  12. QPO Constraints on Neutron Stars

    NASA Technical Reports Server (NTRS)

    Miller, M. Coleman

    2005-01-01

    The kilohertz frequencies of QPOs from accreting neutron star systems imply that they are generated in regions of strong gravity, close to the star. This suggests that observations of the QPOs can be used to constrain the properties of neutron stars themselves, and in particular to inform us about the properties of cold matter beyond nuclear densities. Here we discuss some relatively model-insensitive constraints that emerge from the kilohertz QPOs, as well as recent developments that may hint at phenomena related to unstable circular orbits outside neutron stars.

  13. Automatic generation of computable implementation guides from clinical information models.

    PubMed

    Boscá, Diego; Maldonado, José Alberto; Moner, David; Robles, Montserrat

    2015-06-01

    Clinical information models are increasingly used to describe the contents of Electronic Health Records. Implementation guides are a common specification mechanism used to define such models. They contain, among other reference materials, all the constraints and rules that clinical information must obey. However, these implementation guides typically are oriented to human-readability, and thus cannot be processed by computers. As a consequence, they must be reinterpreted and transformed manually into an executable language such as Schematron or Object Constraint Language (OCL). This task can be difficult and error prone due to the big gap between both representations. The challenge is to develop a methodology for the specification of implementation guides in such a way that humans can read and understand easily and at the same time can be processed by computers. In this paper, we propose and describe a novel methodology that uses archetypes as basis for generation of implementation guides. We use archetypes to generate formal rules expressed in Natural Rule Language (NRL) and other reference materials usually included in implementation guides such as sample XML instances. We also generate Schematron rules from NRL rules to be used for the validation of data instances. We have implemented these methods in LinkEHR, an archetype editing platform, and exemplify our approach by generating NRL rules and implementation guides from EN ISO 13606, openEHR, and HL7 CDA archetypes. PMID:25910958

  14. Design Constraints on a Synthetic Metabolism

    PubMed Central

    Bilgin, Tugce; Wagner, Andreas

    2012-01-01

    A metabolism is a complex network of chemical reactions that converts sources of energy and chemical elements into biomass and other molecules. To design a metabolism from scratch and to implement it in a synthetic genome is almost within technological reach. Ideally, a synthetic metabolism should be able to synthesize a desired spectrum of molecules at a high rate, from multiple different nutrients, while using few chemical reactions, and producing little or no waste. Not all of these properties are achievable simultaneously. We here use a recently developed technique to create random metabolic networks with pre-specified properties to quantify trade-offs between these and other properties. We find that for every additional molecule to be synthesized a network needs on average three additional reactions. For every additional carbon source to be utilized, it needs on average two additional reactions. Networks able to synthesize 20 biomass molecules from each of 20 alternative sole carbon sources need to have at least 260 reactions. This number increases to 518 reactions for networks that can synthesize more than 60 molecules from each of 80 carbon sources. The maximally achievable rate of biosynthesis decreases by approximately 5 percent for every additional molecule to be synthesized. Biochemically related molecules can be synthesized at higher rates, because their synthesis produces less waste. Overall, the variables we study can explain 87 percent of variation in network size and 84 percent of the variation in synthesis rate. The constraints we identify prescribe broad boundary conditions that can help to guide synthetic metabolism design. PMID:22768162

  15. Transversal vibration analysis of an axially moving string with unilateral constraints using the HHT method

    NASA Astrophysics Data System (ADS)

    Xia, Chunlin; Wu, Yangfang; Lu, Qianqian

    2013-08-01

    In this paper, the transversal vibration characteristics of an axially moving string with unilateral constraints were examined using the Hilbert-Huang transform (HHT), due to its wide range of applications. Experiments were conducted on five test cases, and the subsequent analyses were discussed. The experimental results show that the introduction of a guide has the effect of causing low-frequency vibration suppression. The vibration behaviors of the guided segment and the free portion are highly sensitive to the initial tension, the initial clearance between the string and the guide, the transport speed and the guiding length. The details of the string vibrations revealed in this work will be used as a reference for engineering designs and relative system identifications.

  16. Shaping tissues by balancing active forces and geometric constraints

    NASA Astrophysics Data System (ADS)

    Foolen, Jasper; Yamashita, Tadahiro; Kollmannsberger, Philip

    2016-02-01

    The self-organization of cells into complex tissues during growth and regeneration is a combination of physical-mechanical events and biochemical signal processing. Cells actively generate forces at all stages in this process, and according to the laws of mechanics, these forces result in stress fields defined by the geometric boundary conditions of the cell and tissue. The unique ability of cells to translate such force patterns into biochemical information and vice versa sets biological tissues apart from any other material. In this topical review, we summarize the current knowledge and open questions of how forces and geometry act together on scales from the single cell to tissues and organisms, and how their interaction determines biological shape and structure. Starting with a planar surface as the simplest type of geometric constraint, we review literature on how forces during cell spreading and adhesion together with geometric constraints impact cell shape, stress patterns, and the resulting biological response. We then move on to include cell-cell interactions and the role of forces in monolayers and in collective cell migration, and introduce curvature at the transition from flat cell sheets to three-dimensional (3D) tissues. Fibrous 3D environments, as cells experience them in the body, introduce new mechanical boundary conditions and change cell behaviour compared to flat surfaces. Starting from early work on force transmission and collagen remodelling, we discuss recent discoveries on the interaction with geometric constraints and the resulting structure formation and network organization in 3D. Recent literature on two physiological scenarios—embryonic development and bone—is reviewed to demonstrate the role of the force-geometry balance in living organisms. Furthermore, the role of mechanics in pathological scenarios such as cancer is discussed. We conclude by highlighting common physical principles guiding cell mechanics, tissue patterning and

  17. Assessing Multivariate Constraints to Evolution across Ten Long-Term Avian Studies

    PubMed Central

    Teplitsky, Celine; Tarka, Maja; Møller, Anders P.; Nakagawa, Shinichi; Balbontín, Javier; Burke, Terry A.; Doutrelant, Claire; Gregoire, Arnaud; Hansson, Bengt; Hasselquist, Dennis; Gustafsson, Lars; de Lope, Florentino; Marzal, Alfonso; Mills, James A.; Wheelwright, Nathaniel T.; Yarrall, John W.; Charmantier, Anne

    2014-01-01

    Background In a rapidly changing world, it is of fundamental importance to understand processes constraining or facilitating adaptation through microevolution. As different traits of an organism covary, genetic correlations are expected to affect evolutionary trajectories. However, only limited empirical data are available. Methodology/Principal Findings We investigate the extent to which multivariate constraints affect the rate of adaptation, focusing on four morphological traits often shown to harbour large amounts of genetic variance and considered to be subject to limited evolutionary constraints. Our data set includes unique long-term data for seven bird species and a total of 10 populations. We estimate population-specific matrices of genetic correlations and multivariate selection coefficients to predict evolutionary responses to selection. Using Bayesian methods that facilitate the propagation of errors in estimates, we compare (1) the rate of adaptation based on predicted response to selection when including genetic correlations with predictions from models where these genetic correlations were set to zero and (2) the multivariate evolvability in the direction of current selection to the average evolvability in random directions of the phenotypic space. We show that genetic correlations on average decrease the predicted rate of adaptation by 28%. Multivariate evolvability in the direction of current selection was systematically lower than average evolvability in random directions of space. These significant reductions in the rate of adaptation and reduced evolvability were due to a general nonalignment of selection and genetic variance, notably orthogonality of directional selection with the size axis along which most (60%) of the genetic variance is found. Conclusions These results suggest that genetic correlations can impose significant constraints on the evolution of avian morphology in wild populations. This could have important impacts on evolutionary

  18. The putative role of lutein and zeaxanthin as protective agents against age-related macular degeneration: promise of molecular genetics for guiding mechanistic and translational research in the field1234

    PubMed Central

    Neuringer, Martha

    2012-01-01

    Age-related macular degeneration (AMD) is the primary cause of vision loss in elderly people of western European ancestry. Genetic, dietary, and environmental factors affect tissue concentrations of macular xanthophylls (MXs) within retinal cell types manifesting AMD pathology. In this article we review the history and state of science on the putative role of the MXs (lutein, zeaxanthin, and meso-zeaxanthin) in AMD and report findings on AMD-associated genes encoding enzymes, transporters, ligands, and receptors affecting or affected by MXs. We then use this context to discuss emerging research opportunities that offer promise for meaningful investigation and inference in the field. PMID:23053548

  19. Using Public-Private Partnerships to Mitigate Disparities in Access to Genetic Services: Lessons from Wisconsin

    PubMed Central

    Senier, Laura; Kearney, Matthew; Orne, Jason

    2016-01-01

    Purpose This mixed-methods study reports on an outreach clinics program designed to deliver genetic services to medically underserved communities in Wisconsin. Methodology We show the geographic distribution, funding patterns, and utilization trends for outreach clinics over a 20-year period. Interviews with program planners and outreach clinic staff show how external and internal constraints limited the program’s capacity. We compare clinic operations to the conceptual models guiding program design. Findings Our findings show that state health officials had to scale back financial support for outreach clinic activities while healthcare providers faced increasing pressure from administrators to reduce investments in charity care. These external and internal constraints led to a decline in the overall number of patients served. We also find that redistribution of clinics to the Milwaukee area increased utilization among Hispanics but not among African-Americans. Our interviews suggest that these patterns may be a function of shortcomings embedded in the planning models. Implications Planning models have three shortcomings. First, they do not identify the mitigation of health disparities as a specific goal. Second, they fail to acknowledge that partners face escalating profit-seeking mandates that may limit their capacity to provide charity services. Finally, they underemphasize the importance of seeking trusted partners, especially in working with communities that have been historically marginalized. Contribution There has been little discussion about equitably leveraging genetic advances that improve healthcare quality and efficacy. The role of State Health Agencies in mitigating disparities in access to genetic services has been largely ignored in the sociological literature. PMID:27279725

  20. Genetic barcodes

    DOEpatents

    Weier, Heinz -Ulrich G

    2015-08-04

    Herein are described multicolor FISH probe sets termed "genetic barcodes" targeting several cancer or disease-related loci to assess gene rearrangements and copy number changes in tumor cells. Two, three or more different fluorophores are used to detect the genetic barcode sections thus permitting unique labeling and multilocus analysis in individual cell nuclei. Gene specific barcodes can be generated and combined to provide both numerical and structural genetic information for these and other pertinent disease associated genes.

  1. Sex reduces genetic variation: a multidisciplinary review.

    PubMed

    Gorelick, Root; Heng, Henry H Q

    2011-04-01

    For over a century, the paradigm has been that sex invariably increases genetic variation, despite many renowned biologists asserting that sex decreases most genetic variation. Sex is usually perceived as the source of additive genetic variance that drives eukaryotic evolution vis-à-vis adaptation and Fisher's fundamental theorem. However, evidence for sex decreasing genetic variation appears in ecology, paleontology, population genetics, and cancer biology. The common thread among many of these disciplines is that sex acts like a coarse filter, weeding out major changes, such as chromosomal rearrangements (that are almost always deleterious), but letting minor variation, such as changes at the nucleotide or gene level (that are often neutral), flow through the sexual sieve. Sex acts as a constraint on genomic and epigenetic variation, thereby limiting adaptive evolution. The diverse reasons for sex reducing genetic variation (especially at the genome level) and slowing down evolution may provide a sufficient benefit to offset the famed costs of sex.

  2. Paleopopulation genetics.

    PubMed

    Wall, Jeffrey D; Slatkin, Montgomery

    2012-01-01

    Paleopopulation genetics is a new field that focuses on the population genetics of extinct groups and ancestral populations (i.e., populations ancestral to extant groups). With recent advances in DNA sequencing technologies, we now have unprecedented ability to directly assay genetic variation from fossils. This allows us to address issues, such as past population structure, changes in population size, and evolutionary relationships between taxa, at a much greater resolution than can traditional population genetics studies. In this review, we discuss recent developments in this emerging field as well as prospects for the future. PMID:22994357

  3. Physiological and Molecular Aspects of Tolerance to Environmental Constraints in Grain and Forage Legumes

    PubMed Central

    Bargaz, Adnane; Zaman-Allah, Mainassara; Farissi, Mohamed; Lazali, Mohamed; Drevon, Jean-Jacques; Maougal, Rim T.; Carlsson, Georg

    2015-01-01

    Despite the agronomical and environmental advantages of the cultivation of legumes, their production is limited by various environmental constraints such as water or nutrient limitation, frost or heat stress and soil salinity, which may be the result of pedoclimatic conditions, intensive use of agricultural lands, decline in soil fertility and environmental degradation. The development of more sustainable agroecosystems that are resilient to environmental constraints will therefore require better understanding of the key mechanisms underlying plant tolerance to abiotic constraints. This review provides highlights of legume tolerance to abiotic constraints with a focus on soil nutrient deficiencies, drought, and salinity. More specifically, recent advances in the physiological and molecular levels of the adaptation of grain and forage legumes to abiotic constraints are discussed. Such adaptation involves complex multigene controlled-traits which also involve multiple sub-traits that are likely regulated under the control of a number of candidate genes. This multi-genetic control of tolerance traits might also be multifunctional, with extended action in response to a number of abiotic constraints. Thus, concrete efforts are required to breed for multifunctional candidate genes in order to boost plant stability under various abiotic constraints. PMID:26287163

  4. OligArch: A software tool to allow artificially expanded genetic information systems (AEGIS) to guide the autonomous self-assembly of long DNA constructs from multiple DNA single strands

    PubMed Central

    Bradley, Kevin M

    2014-01-01

    Summary Synthetic biologists wishing to self-assemble large DNA (L-DNA) constructs from small DNA fragments made by automated synthesis need fragments that hybridize predictably. Such predictability is difficult to obtain with nucleotides built from just the four standard nucleotides. Natural DNA's peculiar combination of strong and weak G:C and A:T pairs, the context-dependence of the strengths of those pairs, unimolecular strand folding that competes with desired interstrand hybridization, and non-Watson–Crick interactions available to standard DNA, all contribute to this unpredictability. In principle, adding extra nucleotides to the genetic alphabet can improve the predictability and reliability of autonomous DNA self-assembly, simply by increasing the information density of oligonucleotide sequences. These extra nucleotides are now available as parts of artificially expanded genetic information systems (AEGIS), and tools are now available to generate entirely standard DNA from AEGIS DNA during PCR amplification. Here, we describe the OligArch (for "oligonucleotide architecting") software, an application that permits synthetic biologists to engineer optimally self-assembling DNA constructs from both six- and eight-letter AEGIS alphabets. This software has been used to design oligonucleotides that self-assemble to form complete genes from 20 or more single-stranded synthetic oligonucleotides. OligArch is therefore a key element of a scalable and integrated infrastructure for the rapid and designed engineering of biology. PMID:25161743

  5. OligArch: A software tool to allow artificially expanded genetic information systems (AEGIS) to guide the autonomous self-assembly of long DNA constructs from multiple DNA single strands.

    PubMed

    Bradley, Kevin M; Benner, Steven A

    2014-01-01

    Synthetic biologists wishing to self-assemble large DNA (L-DNA) constructs from small DNA fragments made by automated synthesis need fragments that hybridize predictably. Such predictability is difficult to obtain with nucleotides built from just the four standard nucleotides. Natural DNA's peculiar combination of strong and weak G:C and A:T pairs, the context-dependence of the strengths of those pairs, unimolecular strand folding that competes with desired interstrand hybridization, and non-Watson-Crick interactions available to standard DNA, all contribute to this unpredictability. In principle, adding extra nucleotides to the genetic alphabet can improve the predictability and reliability of autonomous DNA self-assembly, simply by increasing the information density of oligonucleotide sequences. These extra nucleotides are now available as parts of artificially expanded genetic information systems (AEGIS), and tools are now available to generate entirely standard DNA from AEGIS DNA during PCR amplification. Here, we describe the OligArch (for "oligonucleotide architecting") software, an application that permits synthetic biologists to engineer optimally self-assembling DNA constructs from both six- and eight-letter AEGIS alphabets. This software has been used to design oligonucleotides that self-assemble to form complete genes from 20 or more single-stranded synthetic oligonucleotides. OligArch is therefore a key element of a scalable and integrated infrastructure for the rapid and designed engineering of biology.

  6. Evaluating the role of reproductive constraints in ant social evolution

    PubMed Central

    Khila, Abderrahman; Abouheif, Ehab

    2010-01-01

    The reproductive division of labour is a key feature of eusociality in ants, where queen and worker castes show dramatic differences in the development of their reproductive organs. To understand the developmental and genetic basis underlying this division of labour, we performed a molecular analysis of ovary function and germ cell development in queens and workers. We show that the processes of ovarian development in queens have been highly conserved relative to the fruitfly Drosophila melanogaster. We also identify specific steps during oogenesis and embryogenesis in which ovarian and germ cell development have been evolutionarily modified in the workers. These modifications, which we call ‘reproductive constraints’, are often assumed to represent neutral degenerations that are a consequence of social evolutionary forces. Based on our developmental and functional analysis of these constraints, however, we propose and discuss the alternative hypothesis that reproductive constraints represent adaptive proximate mechanisms or traits for maintaining social harmony in ants. We apply a multi-level selection framework to help understand the role of these constraints in ant social evolution. A complete understanding of how cooperation, conflict and developmental systems evolve in social groups requires a ‘socio-evo-devo’ approach that integrates social evolutionary and developmental biology. PMID:20083637

  7. Constraints and flexibility in mammalian social behaviour: introduction and synthesis

    PubMed Central

    Kappeler, Peter M.; Barrett, Louise; Blumstein, Daniel T.; Clutton-Brock, Tim H.

    2013-01-01

    This paper introduces a Theme Issue presenting the latest developments in research on the interplay between flexibility and constraint in social behaviour, using comparative datasets, long-term field studies and experimental data from both field and laboratory studies of mammals. We first explain our focus on mammals and outline the main components of their social systems, focusing on variation within- and among-species in numerous aspects of social organization, mating system and social structure. We then review the current state of primarily ultimate explanations of this diversity in social behaviour. We approach the question of how and why the balance between behavioural flexibility and continuity is achieved by discussing the genetic, developmental, ecological and social constraints on hypothetically unlimited behavioural flexibility. We introduce the other contributions to this Theme Issue against this background and conclude that constraints are often crucial to the evolution and expression of behavioural flexibility. In exploring these issues, the enduring relevance of Tinbergen's seminal paper ‘On aims and methods in ethology’, with its advocacy of an integrative, four-pronged approach to studying behaviour becomes apparent: an exceptionally fitting tribute on the 50th anniversary of its publication. PMID:23569286

  8. Mice and Men Environmental Balance, Parts Three and Four of an Integrated Science Sequence, Student Guide, 1970 Edition.

    ERIC Educational Resources Information Center

    Portland Project Committee, OR.

    This student guide is divided into two sections: "Mice and Men" and "Environmental Balance," and constitutes parts three and four of the first year of the Portland Project, a three-year, integrated high school science curriculum. Part One of the guide deals with topics such as cell, reproduction, embryology, genetics, genetic diseases, genetics…

  9. Causality constraints in conformal field theory

    NASA Astrophysics Data System (ADS)

    Hartman, Thomas; Jain, Sachin; Kundu, Sandipan

    2016-05-01

    Causality places nontrivial constraints on QFT in Lorentzian signature, for example fixing the signs of certain terms in the low energy Lagrangian. In d dimensional conformal field theory, we show how such constraints are encoded in crossing symmetry of Euclidean correlators, and derive analogous constraints directly from the conformal bootstrap (analytically). The bootstrap setup is a Lorentzian four-point function corresponding to propagation through a shockwave. Crossing symmetry fixes the signs of certain log terms that appear in the conformal block expansion, which constrains the interactions of low-lying operators. As an application, we use the bootstrap to rederive the well known sign constraint on the (∂ ϕ)4 coupling in effective field theory, from a dual CFT. We also find constraints on theories with higher spin conserved currents. Our analysis is restricted to scalar correlators, but we argue that similar methods should also impose nontrivial constraints on the interactions of spinning operators.

  10. Symmetric scalar constraint for loop quantum gravity

    NASA Astrophysics Data System (ADS)

    Lewandowski, Jerzy; Sahlmann, Hanno

    2015-02-01

    In the framework of loop quantum gravity, we define a new Hilbert space of states which are solutions of a large number of components of the diffeomorphism constraint. On this Hilbert space, using the methods of Thiemann, we obtain a family of gravitational scalar constraints. They preserve the Hilbert space for every choice of lapse function. Thus adjointness and commutator properties of the constraint can be investigated in a straightforward manner. We show how the space of solutions of the symmetrized constraint can be defined by spectral decomposition, and the Hilbert space of physical states by subsequently fully implementing the diffeomorphism constraint. The relationship of the solutions to those resulting from a proposal for a symmetric constraint operator by Thiemann remains to be elucidated.

  11. Constraint-based interactive assembly planning

    SciTech Connect

    Jones, R.E.; Wilson, R.H.; Calton, T.L.

    1997-03-01

    The constraints on assembly plans vary depending on the product, assembly facility, assembly volume, and many other factors. This paper describes the principles and implementation of a framework that supports a wide variety of user-specified constraints for interactive assembly planning. Constraints from many sources can be expressed on a sequencing level, specifying orders and conditions on part mating operations in a number of ways. All constraints are implemented as filters that either accept or reject assembly operations proposed by the planner. For efficiency, some constraints are supplemented with special-purpose modifications to the planner`s algorithms. Replanning is fast enough to enable a natural plan-view-constrain-replan cycle that aids in constraint discovery and documentation. We describe an implementation of the framework in a computer-aided assembly planning system and experiments applying the system to several complex assemblies. 12 refs., 2 figs., 3 tabs.

  12. Constraint Embedding for Multibody System Dynamics

    NASA Technical Reports Server (NTRS)

    Jain, Abhinandan

    2009-01-01

    This paper describes a constraint embedding approach for the handling of local closure constraints in multibody system dynamics. The approach uses spatial operator techniques to eliminate local-loop constraints from the system and effectively convert the system into tree-topology systems. This approach allows the direct derivation of recursive O(N) techniques for solving the system dynamics and avoiding the expensive steps that would otherwise be required for handling the closedchain dynamics. The approach is very effective for systems where the constraints are confined to small-subgraphs within the system topology. The paper provides background on the spatial operator O(N) algorithms, the extensions for handling embedded constraints, and concludes with some examples of such constraints.

  13. Thermodynamic constraints on fluctuation phenomena

    NASA Astrophysics Data System (ADS)

    Maroney, O. J. E.

    2009-12-01

    The relationships among reversible Carnot cycles, the absence of perpetual motion machines, and the existence of a nondecreasing globally unique entropy function form the starting point of many textbook presentations of the foundations of thermodynamics. However, the thermal fluctuation phenomena associated with statistical mechanics has been argued to restrict the domain of validity of this basis of the second law of thermodynamics. Here we demonstrate that fluctuation phenomena can be incorporated into the traditional presentation, extending rather than restricting the domain of validity of the phenomenologically motivated second law. Consistency conditions lead to constraints upon the possible spectrum of thermal fluctuations. In a special case this uniquely selects the Gibbs canonical distribution and more generally incorporates the Tsallis distributions. No particular model of microscopic dynamics need be assumed.

  14. Physical constraints for pathogen movement.

    PubMed

    Schwarz, Ulrich S

    2015-10-01

    In this pedagogical review, we discuss the physical constraints that pathogens experience when they move in their host environment. Due to their small size, pathogens are living in a low Reynolds number world dominated by viscosity. For swimming pathogens, the so-called scallop theorem determines which kinds of shape changes can lead to productive motility. For crawling or gliding cells, the main resistance to movement comes from protein friction at the cell-environment interface. Viruses and pathogenic bacteria can also exploit intracellular host processes such as actin polymerization and motor-based transport, if they present the appropriate factors on their surfaces. Similar to cancer cells that also tend to cross various barriers, pathogens often combine several of these strategies in order to increase their motility and therefore their chances to replicate and spread.

  15. Thermodynamic constraints on fluctuation phenomena.

    PubMed

    Maroney, O J E

    2009-12-01

    The relationships among reversible Carnot cycles, the absence of perpetual motion machines, and the existence of a nondecreasing globally unique entropy function form the starting point of many textbook presentations of the foundations of thermodynamics. However, the thermal fluctuation phenomena associated with statistical mechanics has been argued to restrict the domain of validity of this basis of the second law of thermodynamics. Here we demonstrate that fluctuation phenomena can be incorporated into the traditional presentation, extending rather than restricting the domain of validity of the phenomenologically motivated second law. Consistency conditions lead to constraints upon the possible spectrum of thermal fluctuations. In a special case this uniquely selects the Gibbs canonical distribution and more generally incorporates the Tsallis distributions. No particular model of microscopic dynamics need be assumed.

  16. Atom mapping with constraint programming.

    PubMed

    Mann, Martin; Nahar, Feras; Schnorr, Norah; Backofen, Rolf; Stadler, Peter F; Flamm, Christoph

    2014-01-01

    Chemical reactions are rearrangements of chemical bonds. Each atom in an educt molecule thus appears again in a specific position of one of the reaction products. This bijection between educt and product atoms is not reported by chemical reaction databases, however, so that the "Atom Mapping Problem" of finding this bijection is left as an important computational task for many practical applications in computational chemistry and systems biology. Elementary chemical reactions feature a cyclic imaginary transition state (ITS) that imposes additional restrictions on the bijection between educt and product atoms that are not taken into account by previous approaches. We demonstrate that Constraint Programming is well-suited to solving the Atom Mapping Problem in this setting. The performance of our approach is evaluated for a manually curated subset of chemical reactions from the KEGG database featuring various ITS cycle layouts and reaction mechanisms.

  17. Relativistic Guiding Center Equations

    SciTech Connect

    White, R. B.; Gobbin, M.

    2014-10-01

    In toroidal fusion devices it is relatively easy that electrons achieve relativistic velocities, so to simulate runaway electrons and other high energy phenomena a nonrelativistic guiding center formalism is not sufficient. Relativistic guiding center equations including flute mode time dependent field perturbations are derived. The same variables as used in a previous nonrelativistic guiding center code are adopted, so that a straightforward modifications of those equations can produce a relativistic version.

  18. Sensor Characteristics Reference Guide

    SciTech Connect

    none,

    2013-04-01

    The purpose of the guide is to inform building owners and operators of the current status, capabilities, and limitations of sensor technologies. It is hoped that this guide will aid in the design and procurement process and result in successful implementation of building sensor and control systems. DOE will also use this guide to identify research priorities, develop future specifications for potential market adoption, and provide market clarity through unbiased information.

  19. Geomagnetic main field modeling using magnetohydrodynamic constraints

    NASA Technical Reports Server (NTRS)

    Estes, R. H.

    1985-01-01

    The influence of physical constraints are investigated which may be approximately satisfied by the Earth's liquid core on models of the geomagnetic main field and its secular variation. A previous report describes the methodology used to incorporate nonlinear equations of constraint into the main field model. The application of that methodology to the GSFC 12/83 field model to test the frozen-flux hypothesis and the usefulness of incorporating magnetohydrodynamic constraints for obtaining improved geomagnetic field models is described.

  20. Precision guided antiaircraft munition

    DOEpatents

    Hirschfeld, Tomas B.

    1987-01-01

    A small diameter, 20 mm to 50 mm, guided projectile is used in antiaircraft defense. A pulsing laser designator illuminates the target aircraft. Energy reflected from the aircraft is received by the guided projectile. The guided projectile is fired from a standard weapon but the spining caused by the riflings are removed before active tracking and guidance occurs. The received energy is focused by immersion optics onto a bridge cell. AC coupling and gating removes background and allows steering signals to move extended vanes by means of piezoelectric actuators in the rear of the guided projectile.

  1. Natural constraints, folding, motion, and structural stability in transmembrane helical proteins

    NASA Astrophysics Data System (ADS)

    Harrington, Susan E.; Ben-Tal, Nir

    Transmembrane (TM) helical proteins are of fundamental importance in many diverse biological processes. To understand these proteins functionally, it is necessary to characterize the forces that stabilize them. What are these forces (both within the protein itself and between the protein and membrane) and how do they give rise to the multiple conformational states and complex activity of TM helical proteins? How do they act in concert to fold TM helical proteins, create their low-energy stable states, and guide their motion? These central questions have led to the description of critical natural constraints and partial answers, which we will review. We will then describe how these constraints can be tracked through homologs and proteins of similar folds in order to better understand how amino acid sequence can specify structure and guide motion. Our emphasis throughout will be on structural features of TM helix bundles themselves, but we will also sketch the membrane-related aspects of these questions.

  2. Genetic Engineering

    ERIC Educational Resources Information Center

    Phillips, John

    1973-01-01

    Presents a review of genetic engineering, in which the genotypes of plants and animals (including human genotypes) may be manipulated for the benefit of the human species. Discusses associated problems and solutions and provides an extensive bibliography of literature relating to genetic engineering. (JR)

  3. Optimality criteria design and stress constraint processing

    NASA Technical Reports Server (NTRS)

    Levy, R.

    1982-01-01

    Methods for pre-screening stress constraints into either primary or side-constraint categories are reviewed; a projection method, which is developed from prior cycle stress resultant history, is introduced as an additional screening parameter. Stress resultant projections are also employed to modify the traditional stress-ratio, side-constraint boundary. A special application of structural modification reanalysis is applied to the critical stress constraints to provide feasible designs that are preferable to those obtained by conventional scaling. Sample problem executions show relatively short run times and fewer design cycle iterations to achieve low structural weights; those attained are comparable to the minimum values developed elsewhere.

  4. An introductory review of parallel independent component analysis (p-ICA) and a guide to applying p-ICA to genetic data and imaging phenotypes to identify disease-associated biological pathways and systems in common complex disorders.

    PubMed

    Pearlson, Godfrey D; Liu, Jingyu; Calhoun, Vince D

    2015-01-01

    Complex inherited phenotypes, including those for many common medical and psychiatric diseases, are most likely underpinned by multiple genes contributing to interlocking molecular biological processes, along with environmental factors (Owen et al., 2010). Despite this, genotyping strategies for complex, inherited, disease-related phenotypes mostly employ univariate analyses, e.g., genome wide association. Such procedures most often identify isolated risk-related SNPs or loci, not the underlying biological pathways necessary to help guide the development of novel treatment approaches. This article focuses on the multivariate analysis strategy of parallel (i.e., simultaneous combination of SNP and neuroimage information) independent component analysis (p-ICA), which typically yields large clusters of functionally related SNPs statistically correlated with phenotype components, whose overall molecular biologic relevance is inferred subsequently using annotation software suites. Because this is a novel approach, whose details are relatively new to the field we summarize its underlying principles and address conceptual questions regarding interpretation of resulting data and provide practical illustrations of the method. PMID:26442095

  5. Contribution of genetics to ecological restoration.

    PubMed

    Mijangos, Jose Luis; Pacioni, Carlo; Spencer, Peter B S; Craig, Michael D

    2015-01-01

    Ecological restoration of degraded ecosystems has emerged as a critical tool in the fight to reverse and ameliorate the current loss of biodiversity and ecosystem services. Approaches derived from different genetic disciplines are extending the theoretical and applied frameworks on which ecological restoration is based. We performed a search of scientific articles and identified 160 articles that employed a genetic approach within a restoration context to shed light on the links between genetics and restoration. These articles were then classified on whether they examined association between genetics and fitness or the application of genetics in demographic studies, and on the way the studies informed restoration practice. Although genetic research in restoration is rapidly growing, we found that studies could make better use of the extensive toolbox developed by applied fields in genetics. Overall, 41% of reviewed studies used genetic information to evaluate or monitor restoration, and 59% provided genetic information to guide prerestoration decision-making processes. Reviewed studies suggest that restoration practitioners often overlook the importance of including genetic aspects within their restoration goals. Even though there is a genetic basis influencing the provision of ecosystem services, few studies explored this relationship. We provide a view of research gaps, future directions and challenges in the genetics of restoration.

  6. Science: Grade 7. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  7. Science: Grade 8. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  8. Science: Grade 9. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  9. Science: Grade 5. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  10. Science: Grade 3. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  11. Science: Grade 6. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  12. Neighboring optimal guidance for aeroassisted orbital plane change with G-value constraint

    NASA Astrophysics Data System (ADS)

    Chern, Jeng-Shing; Hsu, Fu-Kuo; Lin, Ching-Chyuan

    In the last decade, the optimal aeroassisted trajectories, either for reentry or orbital transfer, have been investigated extensively. At the same time, the guidance and control problems for these missions are attracting scientists gradually. The purpose of this paper is to develop a neighboring optimal guidance for aeroassisted orbital plane change with G-value constraint. The normal optimal trajectory for maximizing the orbital plane change with G-value constraint is computed with specified initial and final conditions. We then assume that there are small variations in initial values of the state variables, and try to guide the vehicle back to the nominal optimal trajectory under G-value constraint of 2.5 by using the neighboring optimal guidance law developed in this paper. The displacements of the switching points are calculated and discussed.

  13. Closed Loop Guidance with Multiple Constraints for Low Orbit Vehicle Trajectory Optimization

    NASA Astrophysics Data System (ADS)

    Zhang, Rufei; Zhao, Shifan

    Low orbit has features of strong invisibility and penetration, but needs more shutdown energy comparable to high orbit under the same range, which strongly requires studying the problem of delivery capacity optimization for multi-stage launch vehicles. Based on remnant apparent velocity and constraints models, multi-constraint closed-loop guidance with constraints of trajectory maximum height and azimuth was proposed, which adopted elliptical orbit theory and Newton iteration algorithm to optimize trajectory and thrust direction, reached to take full advantage of multi-stage launch vehicle propellant, and guided low orbit vehicle to enter maximum range trajectory. Theory deduction and numerical example demonstrate that the proposed guidance method could extend range and achieve precise control for orbit maximum height and azimuth.

  14. Guide star targeting success for the HEAO-B observatory

    NASA Technical Reports Server (NTRS)

    Farrenkopf, R. L.; Hoffman, D. P.

    1977-01-01

    The statistics associated with the successful selection and acquisition of guide stars as attitude benchmarks for use in reorientation maneuvers of the HEAO-B observatory are considered as a function of the maneuver angle, initial attitude uncertainties, and the pertinent celestial region. Success likelihoods in excess of 0.99 are predicted assuming anticipated gyro and star tracker error sources. The maneuver technique and guide star selection constraints are described in detail. The results presented are specialized numerically to the HEAO-B observatory. However, the analytical techniques developed are considered applicable to broader classes of spacecraft requiring celestial targeting.

  15. Manufacturing Technology. Curriculum Guide.

    ERIC Educational Resources Information Center

    North Dakota State Board for Vocational Education, Bismarck.

    This guide provides the basic foundation to develop a one-semester course based on the cluster concept, manufacturing technology. One of a set of six guides for an industrial arts curriculum at the junior high school level, it suggests activities that allow students (1) to become familiar with and use some of the tools, materials, and processes…

  16. Katimavik Participant Information Guide.

    ERIC Educational Resources Information Center

    OPCAN, Montreal (Quebec).

    The guide provides prospective participants with an overview of Katimavik, a 9-month community volunteer service and learning program for 17- to 21-year-olds sponsored since 1977 by the Canadian Government. The guide describes the application process and computerized random selection procedures; work projects, which may range from building…

  17. User's Guide for SKETCH

    NASA Technical Reports Server (NTRS)

    Hedgley, David R., Jr.

    2000-01-01

    A user's guide for the computer program SKETCH is presented on this disk. SKETCH solves a popular problem in computer graphics-the removal of hidden lines from images of solid objects. Examples and illustrations are included in the guide. Also included is the SKETCH program, so a user can incorporate the information into a particular software system.

  18. Vocational Planning Guide.

    ERIC Educational Resources Information Center

    Dyrenfurth, Michael J.; Elias, John E.

    This guide provides local vocational administrators (LVAs) with information and guidelines to plan vocational programs for their school, district, or community college. The first four chapters outline a four-step planning process. They guide the LVA through (1) establishment of vocational education's place within the community's educational…

  19. Business Management Course Guide.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Vocational Education.

    This course guide is designed for teaching about the U.S. business system. Students are introduced to management functions and the background knowledge/skills necessary to be a successful manager. The guide contains 10 competency goals: (1) nature of U.S. business; (2) environment of business; (3) types of business ownership; (4) management…

  20. Volunteeer's Reference Guide.

    ERIC Educational Resources Information Center

    Armstrong, Julie; And Others

    For Postpartum Education for Parents (PEP) volunteers, this reference guide provides background information about the common concerns of parents. Extensively reviewed for accuracy and content by pediatricians, psychologists, obstetricians, nurses, and childbirth educators, the guide contains a summary discussion of the postpartum infant and…

  1. Valuing Families. Activity Guide.

    ERIC Educational Resources Information Center

    Glashagel, Jerry; Glashagel, Char

    Developed as a resource for family life education, this activity guide can be used to lead experiential learning situations for intergenerational groups by a counselor, in a course, in a family organization like the YMCA, or in the home. The goals of this guide are to increase the self-esteem of each person and to strengthen the family as a human…

  2. Medical Assisting Learning Guides.

    ERIC Educational Resources Information Center

    Meyer, Rose

    Eight student learning guides are provided for a medical assisting program at the secondary, postsecondary, or adult level. Each learning guide is composed of these component parts: a title page that states the task, purpose, program and task numbers, estimated time, and prerequisites; an optional learning contract that includes terminal…

  3. Drafting Lab Management Guide.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Instructional Materials Lab.

    This manual was developed to guide drafting instructors and vocational supervisors in sequencing laboratory instruction and controlling the flow of work for a 2-year machine trades training program. The first part of the guide provides information on program management (program description, safety concerns, academic issues, implementation…

  4. Measurement Practice Guide

    ERIC Educational Resources Information Center

    College and Career Readiness and Success Center, 2014

    2014-01-01

    This discussion guide is part of a larger practice guide designed to help state education agencies (SEAs) define measurement goals, select college and career readiness measures and indicators designed to support those goals, and use the data gathered with those measures and indicators to make informed decisions about college and career readiness…

  5. Women's History Curriculum Guide.

    ERIC Educational Resources Information Center

    Ruthsdotter, Mary, Ed.; Eisenberg, Bonnie, Ed.

    This curriculum guide is designed to facilitate teachers' first efforts to introduce information about women in U.S. history. The guide promotes a multicultural awareness of women's history beginning with the Native Americans and proceeding to current issues of diversity. Activities are divided for grades 1-6 and 7-12 but may be adapted as…

  6. Livestock. Student Learning Guides.

    ERIC Educational Resources Information Center

    Ridge Vocational-Technical Center, Winter Haven, FL.

    These 25 learning guides are self-instructional packets for 25 tasks identified as essential for performance on an entry-level job in livestock production. Each guide is based on a terminal performance objective (task) and 1-4 enabling objectives. For each enabling objective, some or all of these materials may be presented: learning steps (outline…

  7. Ecological Investigations, Curriculum Guide.

    ERIC Educational Resources Information Center

    Washington City Board of Education, NC.

    Activities which stress ecological concepts make up the major portion of this curriculum guide. Designed as a 12 week mini-course for students in grades eight and nine, the guide first presents the course schedule, including time requirements, lists the ecological concepts to be studied, and correlates the concepts with the activities. Following…

  8. Irrigation Systems. Instructor's Guide.

    ERIC Educational Resources Information Center

    Amarillo Coll., TX.

    This guide is intended for use by licensed irrigators who wish to teach others how to design and install residential and commercial irrigation systems. The materials included in the guide have been developed under the assumption that the instructors who use it have little or no formal training as teachers. The first section presents detailed…

  9. Irrigation Systems. Student's Guide.

    ERIC Educational Resources Information Center

    Amarillo Coll., TX.

    This guide is intended for use by individuals preparing for a career in commercial and residential irrigation. The materials included are geared toward students who have had some experience in the irrigation business; they are intended to be presented in 10 six-hour sessions. The first two sections deal with using this guide and preparing for the…

  10. Public Relations Guide.

    ERIC Educational Resources Information Center

    Proctor and Gamble Co., Cincinnati, OH.

    This guide was especially designed for home economists and includes 50 pages of practical ideas and examples on how to set public relations objectives, determine target audiences, work with the media, write releases' and prepare for broadcast interviews. The guide includes definitions of basic terms used in public relations, establishes guidelines…

  11. Consumer Mathematics Curriculum Guide.

    ERIC Educational Resources Information Center

    Louisiana State Dept. of Education, Baton Rouge.

    This guide for high school consumer mathematics (one in a set of curriculum guides developed by Louisiana statewide mathematics curriculum committees) contains a course outline, performance objectives, and coordinated activities designed to teach skills that students will need as citizens and consumers. Background on the development,…

  12. Personal Finance Education Guide.

    ERIC Educational Resources Information Center

    Oregon State Board of Education, Salem.

    The guide was developed to aid teachers in planning and developing programs in personal finance education which will prepare students to function as intelligent consumers. Three case studies illustrating common consumer problems are followed by the body of the guide, focusing on five major topics and incorporating economic, social, and physical…

  13. Medical Assisting Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This guide presents the standard curriculum for technical institutes in Georgia. The curriculum addresses the minimum competencies for a medical assisting program. The program guide is designed to relate primarily to the development of those skills needed by individuals in the medical assisting field, such as medical law and ethics, typing,…

  14. Radiologic Technology Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This guide presents the standard curriculum for technical institutes in Georgia. The curriculum addresses the minimum competencies for a radiologic technology program. The guide contains four major sections. The General Information section contains an introduction giving an overview and defining purpose and objectives; a program description,…

  15. Native Americans: Subject Guide.

    ERIC Educational Resources Information Center

    Bonanni, Mimmo; Etter, Patricia A.

    This annotated subject guide lists reference material that deals with Native Americans and is available in the Arizona State University Libraries. Entries were published 1933-98, but mostly in the 1980s-90s. The guide is not comprehensive, but rather a selective list of resources useful for researching a topic in a variety of fields. The guide…

  16. Geology 12. Curriculum Guide.

    ERIC Educational Resources Information Center

    British Columbia Dept. of Education, Victoria.

    This publication, developed by the Ministry of Education, Province of British Columbia, Canada, is a teaching guide for the Geology 12 course. The course is intended to provide secondary school students with the background and desire to investigate their earth, its materials and its processes. The guide consists of the following four sections: (1)…

  17. Primary Art Resource Guide.

    ERIC Educational Resources Information Center

    Newton Unified School District 373, KS.

    GRADES OR AGES: Primary Grades. SUBJECT MATTER: Art. ORGANIZATION AND PHYSICAL APPEARANCE: The guide begins with a list of topics for art expression. The main body of the guide contains 15 color-coded sections on the following subjects: 1) mobiles and folded paper; 2) collage and photo montage; 3) square paper and mosaics; 4) wax paper and…

  18. Hospitality Services. Curriculum Guide.

    ERIC Educational Resources Information Center

    Texas Tech Univ., Lubbock. Home Economics Curriculum Center.

    This guide, which was developed as part of Texas' home economics education program, is intended to assist teachers of a hospitality services course focusing on the food and lodging segments of the hospitality and tourism industry. The first 40% of the approximately 600-page guide consists of strategies for teaching each of 29 essential…

  19. Nutrition Activities Resource Guide.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Div. of Special Education.

    The resource guide suggests activities to help special education students make appropriate choices about their nutritional habits. It is explained that the activities can be infused into other curriculum areas. The guide consists of five themes and includes performance objectives for each: foods eaten at school (planning a school lunch, keeping a…

  20. INDUSTRIAL RADIOGRAPHY INSTRUCTOR'S GUIDE.

    ERIC Educational Resources Information Center

    Bureau of Adult, Vocational, and Technical Education (DHEW/OE), Washington, DC. Div. of Vocational and Technical Education.

    THIS LABORATORY GUIDE WAS DEVELOPED FOR AN 80-HOUR COURSE IN INDUSTRIAL RADIOGRAPHY FOR HIGH SCHOOL GRADUATES TRAINING TO BECOME BEGINNING RADIOGRAPHERS. IT IS USED IN CONJUNCTION WITH TWO OTHER VOLUMES--(1) INDUSTRIAL RADIOGRAPHY INSTRUCTOR'S GUIDE, AND (2) INUDSTRIAL RADIOGRAPHY MANUAL. THE PROGRAM WAS DEVELOPED BY A COMMITTEE OF REPRESENTATIVES…

  1. Library Automation Style Guide.

    ERIC Educational Resources Information Center

    Gaylord Bros., Liverpool, NY.

    This library automation style guide lists specific terms and names often used in the library automation industry. The terms and/or acronyms are listed alphabetically and each is followed by a brief definition. The guide refers to the "Chicago Manual of Style" for general rules, and a notes section is included for the convenience of individual…

  2. Marketing Education Curriculum Guide.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This curriculum guide is intended to provide a common core of competencies from which to design an effective secondary marketing education program. Introductory materials include a definition of marketing education, objectives, outline of instructional content, and questions and answers regarding the curriculum guide. These practical materials are…

  3. Recycling Study Guide.

    ERIC Educational Resources Information Center

    Hallowell, Anne; And Others

    This study guide was designed to help teachers and students understand the problems surrounding solid wastes. It includes an overview of solid waste and recycling, a glossary, suggested activities and a list of resource publications, audiovisual materials and organizations. There are 19 activity suggestions included in this guide designed for use…

  4. Instructional Guide for Cosmetology.

    ERIC Educational Resources Information Center

    Virginia Polytechnic Inst. and State Univ., Blacksburg. Dept. of Education.

    Intended as a tool for cosmetology teachers in Virginia public and private schools, the document is an instructional guide which offers 12 units of study, arranged in a three year course. Materials covered help prepare students for licensure in the State of Virginia and the guide is designed to cover the 1,500 hours required to be spent in the…

  5. Curriculum Guide for Metals.

    ERIC Educational Resources Information Center

    Oregon State Board of Education, Salem. Div. of Community Colleges and Career Education.

    Developed through a cooperative effort by industry and education, this curriculum guide outlines the basic skills and knowledge necessary for entry-level competencies in the broad field of metals, or for entrance into an apprenticeship, post-high school, or university program. This guide is one of several developed for Oregon's new approach to…

  6. Oregon Trail Teacher's Guide.

    ERIC Educational Resources Information Center

    National Park Service (Dept. of Interior), Washington, DC.

    The road to the U.S. West, known as the Oregon Trail, had its first real traffic in 1843 when a group of about 1000 people left Independence, Missouri and traveled west. This teacher's guide contains short descriptions of the main landmarks and stopping points that were significant along the northwest portion of the Oregon Trail. The guide is…

  7. Conquistadors. Teaching Guide.

    ERIC Educational Resources Information Center

    Larson, Susan Booth

    This teaching guide is comprised of four interdisciplinary units dealing with the expeditions of conquistadors in the New World: (1) "Cortes and the Aztecs: Different Views of the World"; (2) "Pizarro and the Incas: The 'What Ifs?' of History"; (3) "Orellana and the Amazon: Human and Environmental Issues"; and (4) "Teaching Guide for Cabeza de…

  8. Spanish Curriculum Guide.

    ERIC Educational Resources Information Center

    Wicklund, Jacqueline

    This guide delineates the scope and sequence of Spanish instruction in both junior and senior high schools indicating instructional goals in terms of behavioral objectives. Following a review of the Bloomington, Minnesota, school of philosophy and a discussion of the design of the foreign language behavioral objectives in the guide, the manual…

  9. Educator's Guide to Perspectives.

    ERIC Educational Resources Information Center

    Procter and Gamble Educational Services, Cincinnati, OH.

    This teaching guide was designed to implement eight teaching units based on specific events or periods in history. The learning packet was developed to give educators and students a view of the parallel growth of our country and its business and industry. The guide presents: (1) an overview of each of the teaching units; (2) guidelines for using…

  10. Soviet Arts Curriculum Guide.

    ERIC Educational Resources Information Center

    San Diego County Office of Education, CA.

    This extensive curriculum guide was written in conjunction with the San Diego Arts Festival of Soviet Arts in 1989. It aimed to provide teachers with insights and ideas about arts in the Soviet Union before, during, and after the Arts Festival. A curriculum model is presented at the beginning of the guide to illustrate how the lessons were…

  11. Guided Learning at Work.

    ERIC Educational Resources Information Center

    Billett, Stephen

    2000-01-01

    Guided learning (questioning, diagrams/analogies, modeling, coaching) was studied through critical incident interviews in five workplaces. Participation in everyday work activities was the most effective contributor to workplace learning. Organizational readiness and the efficacy of guided learning in resolving novel tasks were also important. (SK)

  12. Latin Curriculum Guide.

    ERIC Educational Resources Information Center

    Lee, Agnes; Stevens, Patrick

    This guide delineates the scope and sequence of Latin instruction in levels 1-3 in terms of behavioral objectives. Following a review of the Bloomington, Minnesota, school philosophy and a discussion of the design of foreign language behavioral objectives on which the guide is based, the manual discusses expected terminal behavior in the level 1…

  13. GEOMETRY, TENTATIVE GUIDES.

    ERIC Educational Resources Information Center

    KLIER, KATHERINE M.

    PRESENTED IS A FUSED COURSE IN PLANE, SOLID, AND COORDINATE GEOMETRY. ELEMENTARY SET THEORY, LOGIC, AND THE PRINCIPLE OF SEPARATION PROVIDE UNIFYING THREADS THROUGHOUT THE TEXT. THE TWO CURRICULUM GUIDES HAVE BEEN PREPARED FOR USE WITH TWO DIFFERENT TEXTS. EITHER CURRICULUM GUIDE MAY BE USED DEPENDING UPON THE CHOICE OF THE TEACHER AND THE NEEDS…

  14. First Business Guide.

    ERIC Educational Resources Information Center

    Small Business Administration, Washington, DC. Office of Business Development.

    This guide offers first-time business persons information as well as administrative and operational techniques for one-person business enterprises that have low initial start-up costs and low operational and overhead costs. These one-person businesses can be home based or have site locations outside the home. Included in this guide is a list of…

  15. Welding. Student Learning Guides.

    ERIC Educational Resources Information Center

    Ridge Vocational-Technical Center, Winter Haven, FL.

    These 23 learning guides are self-instructional packets for 23 tasks identified as essential for performance on an entry-level job in welding. Each guide is based on a terminal performance objective (task) and 1-4 enabling objectives. For each enabling objective, some or all of these materials may be presented: learning steps (outline of student…

  16. Understanding Math - Teachers Guide.

    ERIC Educational Resources Information Center

    Wyks, Hollis W.; Austin, Robert J.

    The teacher's guide for the remedial text-workbook "Understanding Math" discusses instruction of the deaf student. An answer key for workbooks 1 and 2, a section with masters for transparencies to be used for games and activities and for teaching fractions, and two patterns for making geometric solids are included in the guide. For workbooks 1 and…

  17. Curriculum Guide Construction Cluster.

    ERIC Educational Resources Information Center

    Kline, Ken

    As part of a model construction cluster curriculum development project, this guide was developed and implemented in the Beaverton (Oregon) School District. The curriculum guide contains 16 units covering the following topics: introduction to construction jobs; safety and first aid; blueprint readings; basic mathematics; site work; framing; roofing…

  18. Vocational Carpentry Curriculum Guide.

    ERIC Educational Resources Information Center

    Virginia Polytechnic Inst. and State Univ., Blacksburg. Dept. of Education.

    The carpentry curriculum guide was developed as a basic guide to be used by instructors in formulating their own courses of study. The material is designed for use in vocational carpentry classes at grade levels 10, 11, and 12. Planned as a two-year sequence, it incorporates 1080 class hours of instruction and emphasizes light or residential type…

  19. Traffic Safety Education Guide.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Curriculum Development.

    This guide, intended for administrators, curriculum developers, and teachers, provides outlines and suggestions for strategies and materials needed to achieve the goals and objectives of the safety education program. The guide covers the following topics: a broad examination of the highway system; the responsibilities highway users have toward…

  20. Agriculture, Environmental Education Guide.

    ERIC Educational Resources Information Center

    Project I-C-E, Green Bay, WI.

    This agriculture guide, for use at the secondary level, is one of a series of guides, K-12, which were developed by teachers to help introduce environmental education into the total curriculum. Environmental problems are present in every community where agriculture education is offered, and therefore many agriculture teachers have included some…

  1. BONES, TEACHER'S GUIDE.

    ERIC Educational Resources Information Center

    Elementary Science Study, Newton, MA.

    THIS GUIDE WAS DEVELOPED FOR USE WITH THE ELEMENTARY SCIENCE STUDY UNIT ON "BONES.""BONES" HAS BEEN TAUGHT IN THE FOURTH GRADE AND REQUIRES FROM 10 TO 25 LESSONS, DEPENDING ON THE NUMBER OF ACTIVITIES USED. THE GUIDE DOES NOT PROVIDE DETAILED INSTRUCTION FOR CONDUCTING CLASSES, BUT RATHER SOME POSSIBLE ACTIVITIES, AND LEAVES THE DAY-TO-DAY…

  2. Cutting Parameters Optimization and Constraints Investigation for Turning Process by GA with Self-Organizing Adaptive Penalty Strategy

    NASA Astrophysics Data System (ADS)

    Ahmad, Nafis; Tanaka, Tomohisa; Saito, Yoshio

    For efficient use of machine tools at optimum cutting condition, it is necessary to find a suitable optimization method, which can find optimum feasible solution rapidly and explain the constraints as well. As the actual turning process parameter optimization is highly constrained and nonlinear, a modified Genetic Algorithm with Self Organizing Adaptive Penalty (SOAP) strategy is used to find the optimum cutting condition and to get clear idea of constraints at the optimum condition. Unit production cost is the objective function while limits of the cutting force, power, surface finish, stability condition, tool-chip interface temperature and available rotational speed in the machine tool are considered as the constraints. The result shows that our approach of GA with SOAP converges quickly by focusing on the boundary of the feasible and infeasible solution space created by constraints and also identifies the critical and non-critical constraints at the optimum condition.

  3. Genetics of inherited cardiomyopathy

    PubMed Central

    Jacoby, Daniel; McKenna, William J.

    2012-01-01

    During the past two decades, numerous disease-causing genes for different cardiomyopathies have been identified. These discoveries have led to better understanding of disease pathogenesis and initial steps in the application of mutation analysis in the evaluation of affected individuals and their family members. As knowledge of the genetic abnormalities, and insight into cellular and organ biology has grown, so has appreciation of the level of complexity of interaction between genotype and phenotype across disease states. What were initially thought to be one-to-one gene-disease correlates have turned out to display important relational plasticity dependent in large part on the genetic and environmental backgrounds into which the genes of interest express. The current state of knowledge with regard to genetics of cardiomyopathy represents a starting point to address the biology of disease, but is not yet developed sufficiently to supplant clinically based classification systems or, in most cases, to guide therapy to any significant extent. Future work will of necessity be directed towards elucidation of the biological mechanisms of both rare and common gene variants and environmental determinants of plasticity in the genotype–phenotype relationship with the ultimate goal of furthering our ability to identify, diagnose, risk stratify, and treat this group of disorders which cause heart failure and sudden death in the young. PMID:21810862

  4. Phonological Constraint Induction in a Connectionist Network: Learning OCP-Place Constraints from Data

    ERIC Educational Resources Information Center

    Alderete, John; Tupper, Paul; Frisch, Stefan A.

    2013-01-01

    A significant problem in computational language learning is that of inferring the content of well-formedness constraints from input data. In this article, we approach the constraint induction problem as the gradual adjustment of subsymbolic constraints in a connectionist network. In particular, we develop a multi-layer feed-forward network that…

  5. Electrostatically Guided Rydberg Positronium.

    PubMed

    Deller, A; Alonso, A M; Cooper, B S; Hogan, S D; Cassidy, D B

    2016-08-12

    We report experiments in which positronium (Ps) atoms were guided using inhomogeneous electric fields. Ps atoms in Rydberg-Stark states with principal quantum number n=10 and electric dipole moments up to 610 D were prepared via two-color two-photon optical excitation in the presence of a 670  V cm^{-1} electric field. The Ps atoms were created at the entrance of a 0.4 m long electrostatic quadrupole guide, and were detected at the end of the guide via annihilation gamma radiation. When the lasers were tuned to excite low-field-seeking Stark states, a fivefold increase in the number of atoms reaching the end of the guide was observed, whereas no signal was detected when high-field-seeking states were produced. The data are consistent with the calculated geometrical guide acceptance. PMID:27563960

  6. Electrostatically Guided Rydberg Positronium

    NASA Astrophysics Data System (ADS)

    Deller, A.; Alonso, A. M.; Cooper, B. S.; Hogan, S. D.; Cassidy, D. B.

    2016-08-01

    We report experiments in which positronium (Ps) atoms were guided using inhomogeneous electric fields. Ps atoms in Rydberg-Stark states with principal quantum number n =10 and electric dipole moments up to 610 D were prepared via two-color two-photon optical excitation in the presence of a 670 V cm-1 electric field. The Ps atoms were created at the entrance of a 0.4 m long electrostatic quadrupole guide, and were detected at the end of the guide via annihilation gamma radiation. When the lasers were tuned to excite low-field-seeking Stark states, a fivefold increase in the number of atoms reaching the end of the guide was observed, whereas no signal was detected when high-field-seeking states were produced. The data are consistent with the calculated geometrical guide acceptance.

  7. Electrician's Helper. Coordinator's Guide. Individualized Study Guide.

    ERIC Educational Resources Information Center

    Stotts, Danny

    This guide is designed to assist teacher-coordinators supervising cooperative education programs for electrician's helpers in helping students complete a set of individualized, competency-based training activities dealing with electricity and electrical circuits and equipment. The first part of the manual includes a progress chart, a study guide…

  8. Plumber's Helper. Coordinator's Guide. Individualized Study Guide.

    ERIC Educational Resources Information Center

    Traylor, Charles R.

    This individualized, competency-based study guide is designed to assist teacher-coordinators supervising cooperative education programs for plumber's helpers in providing students with general information for immediate reinforcement on the job and developing an understanding of the job prior to employment. A progress chart is provided to allow the…

  9. Gaining Algorithmic Insight through Simplifying Constraints.

    ERIC Educational Resources Information Center

    Ginat, David

    2002-01-01

    Discusses algorithmic problem solving in computer science education, particularly algorithmic insight, and focuses on the relevance and effectiveness of the heuristic simplifying constraints which involves simplification of a given problem to a problem in which constraints are imposed on the input data. Presents three examples involving…

  10. Domain General Constraints on Statistical Learning

    ERIC Educational Resources Information Center

    Thiessen, Erik D.

    2011-01-01

    All theories of language development suggest that learning is constrained. However, theories differ on whether these constraints arise from language-specific processes or have domain-general origins such as the characteristics of human perception and information processing. The current experiments explored constraints on statistical learning of…

  11. Constraints on Noun Incorporation in Korean.

    ERIC Educational Resources Information Center

    Khym, Hangyoo

    1997-01-01

    A study of the noun incorporation phenomenon in Korean suggests that noun incorporation occurs at D-structure and obeys the Head Movement Constraint syntactically, and the Theme-Only Constraint semantically. First, the structure of "sunrise"-type words is identified, showing that before derivation through nominalization of the affix "-i,"…

  12. Trimodal interpretation of constraints for planning

    NASA Technical Reports Server (NTRS)

    Krieger, David; Brown, Richard

    1987-01-01

    Constraints are used in the CAMPS knowledge based planning system to represent those propositions that must be true for a plan to be acceptable. CAMPS introduces the make-mode for interpreting a constraint. Given an unsatisfied constraint, make evaluation mode suggests planning actions which, if taken, would result in a modified plan in which the constraint in question may be satisfied. These suggested planning actions, termed delta-tuples, are the raw material of intelligent plan repair. They are used both in debugging an almost-right plan and in replanning due to changing situations. Given a defective plan in which some set of constraints are violated, a problem solving strategy selects one or more constraints as a focus of attention. These selected constraints are evaluated in the make-mode to produce delta-tuples. The problem solving strategy then reviews the delta-tuples according to its application and problem-specific criteria to find the most acceptable change in terms of success likelihood and plan disruption. Finally, the problem solving strategy makes the suggested alteration to the plan and then rechecks constraints to find any unexpected consequences.

  13. The "No Crossing Constraint" in Autosegmental Phonology.

    ERIC Educational Resources Information Center

    Coleman, John; Local, John

    A discussion of autosegmental phonology (AP), a theory of phonological representation that uses graphs rather than strings as the central data structure, considers its principal constraint, the "No Crossing Constraint" (NCC). The NCC is the statement that in a well-formed autosegmental diagram, lines of association may not cross. After an…

  14. The genetic basis of complex human behaviors.

    PubMed

    Plomin, R; Owen, M J; McGuffin, P

    1994-06-17

    Quantitative genetic research has built a strong case for the importance of genetic factors in many complex behavioral disorders and dimensions in the domains of psychopathology, personality, and cognitive abilities. Quantitative genetics can also provide an empirical guide and a conceptual framework for the application of molecular genetics. The success of molecular genetics in elucidating the genetic basis of behavioral disorders has largely relied on a reductionistic one gene, one disorder (OGOD) approach in which a single gene is necessary and sufficient to develop a disorder. In contrast, a quantitative trait loci (QTL) approach involves the search for multiple genes, each of which is neither necessary nor sufficient for the development of a trait. The OGOD and QTL approaches have both advantages and disadvantages for identifying genes that affect complex human behaviors.

  15. Hanford's Cleanup Constraints and Challenges

    SciTech Connect

    Reichmuth, Barbara A.; Lesperance, Ann M.; Adams, J. F.; Schlender, Michael H.

    2002-08-02

    The framework for the environmental cleanup decisions made at the Hanford is complex and multi-faceted. There are numerous interfaces and decision pathways. In recent years, the complexities and inter-relatedness of the various interfaces have fostered an environment of frustration and distrust amongst the decision makers. The major stakeholders for the Hanford Cleanup are The U.S. Department of Energy (DOE), the Washington State Department of Ecology (Ecology), and The Environmental Protection Agency (EPA) Region 10. DOE has two field offices at Hanford, the Richland Operations Office (RL) and the Office of River Protection (ORP). Each party has a legitimate jurisdiction over the cleanup and none of the parties can make key decision independent of the other parties. In 1989, DOE entered into a compliance agreement with the regulators (the Hanford Federal Facility Agreement and Consent Order), which established a regulatory framework and compliance milestones for cleanup of the Hanford Site. The purpose of this paper will be to articulate: 1) The process used to collect and analyze the information on cleanup constraints, 2) The technical analysis provided to Hanford decision makers, 3) The principles used to enhance decision making among the decision makers and stakeholders, and 4)How this process is leading to outcomes and eliminating barriers to Hanford cleanup.

  16. Optimal Stopping with Information Constraint

    SciTech Connect

    Lempa, Jukka

    2012-10-15

    We study the optimal stopping problem proposed by Dupuis and Wang (Adv. Appl. Probab. 34:141-157, 2002). In this maximization problem of the expected present value of the exercise payoff, the underlying dynamics follow a linear diffusion. The decision maker is not allowed to stop at any time she chooses but rather on the jump times of an independent Poisson process. Dupuis and Wang (Adv. Appl. Probab. 34:141-157, 2002), solve this problem in the case where the underlying is a geometric Brownian motion and the payoff function is of American call option type. In the current study, we propose a mild set of conditions (covering the setup of Dupuis and Wang in Adv. Appl. Probab. 34:141-157, 2002) on both the underlying and the payoff and build and use a Markovian apparatus based on the Bellman principle of optimality to solve the problem under these conditions. We also discuss the interpretation of this model as optimal timing of an irreversible investment decision under an exogenous information constraint.

  17. Volcanological constraints of Archaean tectonics

    NASA Technical Reports Server (NTRS)

    Thurston, P. C.; Ayres, L. D.

    1986-01-01

    Volcanological and trace element geochemical data can be integrated to place some constraints upon the size, character and evolutionary history of Archean volcanic plumbing, and hence indirectly, Archean tectonics. The earliest volcanism in any greenhouse belt is almost universally tholeitic basalt. Archean mafic magma chambers were usually the site of low pressure fractionation of olivine, plagioclase and later Cpx + or - an oxide phase during evolution of tholeitic liquids. Several models suggest basalt becoming more contaminated by sial with time. Data in the Uchi Subprovince shows early felsic volcanics to have fractionated REE patterns followed by flat REE pattern rhyolites. This is interpreted as initial felsic liquids produced by melting of a garnetiferous mafic source followed by large scale melting of LIL-rich sial. Rare andesites in the Uchi Subprovince are produced by basalt fractionation, direct mantle melts and mixing of basaltic and tonalitic liquids. Composite dikes in the Abitibi Subprovince have a basaltic edge with a chill margin, a rhyolitic interior with no basalt-rhyolite chill margin and partially melted sialic inclusions. Ignimbrites in the Uchi and Abitibi Subprovinces have mafic pumice toward the top. Integration of these data suggest initial mantle-derived basaltic liquids pond in a sialic crust, fractionate and melt sial. The inirial melts low in heavy REE are melts of mafic material, subsequently melting of adjacent sial produces a chamber with a felsic upper part underlain by mafic magma.

  18. Solar system constraints on disformal gravity theories

    NASA Astrophysics Data System (ADS)

    Ip, Hiu Yan; Sakstein, Jeremy; Schmidt, Fabian

    2015-10-01

    Disformal theories of gravity are scalar-tensor theories where the scalar couples derivatively to matter via the Jordan frame metric. These models have recently attracted interest in the cosmological context since they admit accelerating solutions. We derive the solution for a static isolated mass in generic disformal gravity theories and transform it into the parameterised post-Newtonian form. This allows us to investigate constraints placed on such theories by local tests of gravity. The tightest constraints come from preferred-frame effects due to the motion of the Solar System with respect to the evolving cosmological background field. The constraints we obtain improve upon the previous solar system constraints by two orders of magnitude, and constrain the scale of the disformal coupling for generic models to ℳ gtrsim 100 eV. These constraints render all disformal effects irrelevant for cosmology.

  19. Solar system constraints on disformal gravity theories

    SciTech Connect

    Ip, Hiu Yan; Schmidt, Fabian; Sakstein, Jeremy E-mail: jeremy.sakstein@port.ac.uk

    2015-10-01

    Disformal theories of gravity are scalar-tensor theories where the scalar couples derivatively to matter via the Jordan frame metric. These models have recently attracted interest in the cosmological context since they admit accelerating solutions. We derive the solution for a static isolated mass in generic disformal gravity theories and transform it into the parameterised post-Newtonian form. This allows us to investigate constraints placed on such theories by local tests of gravity. The tightest constraints come from preferred-frame effects due to the motion of the Solar System with respect to the evolving cosmological background field. The constraints we obtain improve upon the previous solar system constraints by two orders of magnitude, and constrain the scale of the disformal coupling for generic models to ℳ ∼> 100 eV. These constraints render all disformal effects irrelevant for cosmology.

  20. Evolutionary constraints and the neutral theory. [mutation-caused nucleotide substitutions in DNA

    NASA Technical Reports Server (NTRS)

    Jukes, T. H.; Kimura, M.

    1984-01-01

    The neutral theory of molecular evolution postulates that nucleotide substitutions inherently take place in DNA as a result of point mutations followed by random genetic drift. In the absence of selective constraints, the substitution rate reaches the maximum value set by the mutation rate. The rate in globin pseudogenes is about 5 x 10 to the -9th substitutions per site per year in mammals. Rates slower than this indicate the presence of constraints imposed by negative (natural) selection, which rejects and discards deleterious mutations.

  1. Arthropod Genetics.

    ERIC Educational Resources Information Center

    Zumwalde, Sharon

    2000-01-01

    Introduces an activity on arthropod genetics that involves phenotype and genotype identification of the creature and the construction process. Includes a list of required materials and directions to build a model arthropod. (YDS)

  2. Genetic Discrimination

    MedlinePlus

    ... Medicine Working Group New Horizons and Research Patient Management Policy and Ethics Issues Quick Links for Patient Care ... genetic discrimination. April 25, 2007, Statement of Administration Policy, Office of Management and Budget Official Statement from the Office of ...

  3. Ciona Genetics

    PubMed Central

    Veeman, Michael T.; Chiba, Shota; Smith, William C.

    2010-01-01

    Ascidians, such as Ciona, are invertebrate chordates with simple embryonic body plans and small, relatively non-redundant genomes. Ciona genetics is in its infancy compared to many other model systems, but it provides a powerful method for studying this important vertebrate outgroup. Here we give basic methods for genetic analysis of Ciona, including protocols for controlled crosses both by natural spawning and by the surgical isolation of gametes; the identification and propagation of mutant lines; and strategies for positional cloning. PMID:21805273

  4. Ethical aspects of genetic testing.

    PubMed

    Carter, M A

    2001-07-01

    This article explores ethical concerns and emerging dilemmas associated with the proliferation of information resulting from the extraordinary advances in molecular genetics. It provides an overview of the ethical and legal challenges associated with predictive testing for inherited disease currently being addressed in the literature. Finally, it offers a framework of ethical principles that can be used to guide nurses and other practitioners in the appropriate application of research findings to the clinical practice setting. The ethical guidelines of self-determination, benefit-burden ratio, and justice promulgated in The Belmont Report are interpreted in the new context of predictive genetic testing. The author concludes by discussing how to balance the technical imperative to advance genetic knowledge for the sake of human health with the ethical imperative to preserve the fundamental rights and liberties of both individuals and communities who are its recipients.

  5. Natural Constraints to Species Diversification.

    PubMed

    Lewitus, Eric; Morlon, Hélène

    2016-08-01

    Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades) within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the deep-time evolution of

  6. Hydrogeologic Constraints on Yucatan's Development.

    PubMed

    Doehring, D O; Butler, J H

    1974-11-15

    The Republic of Mexico has an ambitious and effective national water program. The Secretaria de Recursos Hidraulicos (SRH), whose director has cabinet rank in the federal government, is one of the most professionally distinguished government agencies of its kind in the Americas. Resources for the Future, Inc., has been assisting the World Bank with a water planning study which the Bank is undertaking jointly with the Mexican government. The study is intended to provide guidelines for the development of government policies and projects designed to bring about the most efficient use of Mexico's water resources. However, to date, their study has not been directed toward the growing problems of the northern Yucatáan Peninsula which are discussed here. LeGrand (13) suggested that man has inherited a harsh environment in carbonate terranes. In the case of the northern Yucatán Peninsula, the physical environment creates a set of hydrogeologic constraints to future economic and social development. Planning for intermediate and long-range land use on the peninsula must be related directly to the limited and fragile groundwater source. Continued contamination will make future aquifer management a difficult challenge for federal, state, and territorial agencies. We conclude that any strategy for long-range land use in the study area should include establishment of a regional aquifermonitoring network for long-term measurements of key hydrogeologic parameters, including precipitation, evapotranspiration, water table elevations, and water quality. Information from this network would flow into a central facility for storage, interpretation, and analysis. At present the SRH is collecting some of these data. Expansion of the existing program to provide sound information for regional planning will greatly benefit present as well as future generations. If such a program is implemented, it will represent a model for regional planning in other tropical and subtropical karstic

  7. Natural Constraints to Species Diversification

    PubMed Central

    Lewitus, Eric; Morlon, Hélène

    2016-01-01

    Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades) within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the deep-time evolution of

  8. Natural Constraints to Species Diversification.

    PubMed

    Lewitus, Eric; Morlon, Hélène

    2016-08-01

    Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades) within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the deep-time evolution of

  9. Ventilation best practices guide

    SciTech Connect

    Dorgan, C.B.; Dorgan, C.E.

    1996-07-01

    The intent of this Guide is to provide utility marketing and engineering personnel with information on how to identify indoor air quality (IAQ) problems, the current standards relating to IAQ and examples of what typically causes IAQ problems in commercial buildings. The Guide is written assuming that the reader has limited knowledge of heating, ventilating and air conditioning (HVAC) systems and that they are new to the IAQ arena. Also included in the Guide is a discussion of new electric technologies which are energy efficient and maintain a high level of IAQ.

  10. Manufacturing Planning Guide

    NASA Technical Reports Server (NTRS)

    Waid, Michael

    2011-01-01

    Manufacturing process, milestones and inputs are unknowns to first-time users of the manufacturing facilities. The Manufacturing Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their project engineering personnel in manufacturing planning and execution. Material covered includes a roadmap of the manufacturing process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, products, and inputs necessary to define test scope, cost, and schedule are included as an appendix to the guide.

  11. Lagrangian systems with higher order constraints

    NASA Astrophysics Data System (ADS)

    Cendra, H.; Grillo, S. D.

    2007-05-01

    A class of mechanical systems subject to higher order constraints (i.e., constraints involving higher order derivatives of the position of the system) are studied. We call them higher order constrained systems (HOCSs). They include simplified models of elastic rolling bodies, and also the so-called generalized nonholonomic systems (GNHSs), whose constraints only involve the velocities of the system (i.e., first order derivatives in the position of the system). One of the features of this kind of systems is that D'Alembert's principle (or its nonlinear higher order generalization, the Chetaev's principle) is not necessarily satisfied. We present here, as another interesting example of HOCS, systems subjected to friction forces, showing that those forces can be encoded in a second order kinematic constraint. The main aim of the paper is to show that every HOCS is equivalent to a GNHS with linear constraints, in a canonical way. That is to say, systems with higher order constraints can be described in terms of one with linear constraints in velocities. We illustrate this fact with a system with friction and with Rocard's model [Dynamique Générale des Vibrations (1949), Chap. XV, p. 246 and L'instabilité en Mécanique; Automobiles, Avions, Ponts Suspendus (1954)] of a pneumatic tire. As a by-product, we introduce some applications on higher order tangent bundles, which we expect to be useful for the study of intrinsic aspects of the geometry of such bundles.

  12. Detecting genetic responses to environmental change.

    PubMed

    Hoffmann, Ary A; Willi, Yvonne

    2008-06-01

    Changes in environmental conditions can rapidly shift allele frequencies in populations of species with relatively short generation times. Frequency shifts might be detectable in neutral genetic markers when stressful conditions cause a population decline. However, frequency shifts that are diagnostic of specific conditions depend on isolating sets of genes that are involved in adaptive responses. Shifts at candidate loci underlying adaptive responses and DNA regions that control their expression have now been linked to evolutionary responses to pollution, global warming and other changes. Conversely, adaptive constraints, particularly in physiological traits, are recognized through DNA decay in candidate genes. These approaches help researchers and conservation managers understand the power and constraints of evolution.

  13. Specific Genetic Disorders

    MedlinePlus

    ... of Genetic Terms Definitions for genetic terms Specific Genetic Disorders Many human diseases have a genetic component. ... Condition in an Adult The Undiagnosed Diseases Program Genetic Disorders Achondroplasia Alpha-1 Antitrypsin Deficiency Antiphospholipid Syndrome ...

  14. Botanic garden genetics: comparison of two cyacad conservation collections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic data can guide the management of plant conservation collections. Direct assay of an ex situ collection’s genetic diversity, measured against wild plant populations, offers insight for conservation efforts. Here we present a carefully chosen case study, Zamia lucayana, selected for its contra...

  15. Non-GMO genetically edited crop plants.

    PubMed

    Kanchiswamy, Chidananda Nagamangala; Malnoy, Mickael; Velasco, Riccardo; Kim, Jin-Soo; Viola, Roberto

    2015-09-01

    Direct delivery of purified Cas9 protein with guide RNA into plant cells, as opposed to plasmid-mediated delivery, displays high efficiency and reduced off-target effects. Following regeneration from edited cells, the ensuing plant is also likely to bypass genetically modified organism (GMO) legislation as the genome editing complex is degraded in the recipient cells. PMID:25978870

  16. Non-GMO genetically edited crop plants.

    PubMed

    Kanchiswamy, Chidananda Nagamangala; Malnoy, Mickael; Velasco, Riccardo; Kim, Jin-Soo; Viola, Roberto

    2015-09-01

    Direct delivery of purified Cas9 protein with guide RNA into plant cells, as opposed to plasmid-mediated delivery, displays high efficiency and reduced off-target effects. Following regeneration from edited cells, the ensuing plant is also likely to bypass genetically modified organism (GMO) legislation as the genome editing complex is degraded in the recipient cells.

  17. QCD unitarity constraints on Reggeon Field Theory

    NASA Astrophysics Data System (ADS)

    Kovner, Alex; Levin, Eugene; Lublinsky, Michael

    2016-08-01

    We point out that the s-channel unitarity of QCD imposes meaningful constraints on a possible form of the QCD Reggeon Field Theory. We show that neither the BFKL nor JIMWLK nor Braun's Hamiltonian satisfy the said constraints. In a toy, zero transverse dimensional case we construct a model that satisfies the analogous constraint and show that at infinite energy it indeed tends to a "black disk limit" as opposed to the model with triple Pomeron vertex only, routinely used as a toy model in the literature.

  18. Astrophysical and cosmological constraints to neutrino properties

    NASA Technical Reports Server (NTRS)

    Kolb, Edward W.; Schramm, David N.; Turner, Michael S.

    1989-01-01

    The astrophysical and cosmological constraints on neutrino properties (masses, lifetimes, numbers of flavors, etc.) are reviewed. The freeze out of neutrinos in the early Universe are discussed and then the cosmological limits on masses for stable neutrinos are derived. The freeze out argument coupled with observational limits is then used to constrain decaying neutrinos as well. The limits to neutrino properties which follow from SN1987A are then reviewed. The constraint from the big bang nucleosynthesis on the number of neutrino flavors is also considered. Astrophysical constraints on neutrino-mixing as well as future observations of relevance to neutrino physics are briefly discussed.

  19. Black hole thermodynamics from Euclidean horizon constraints.

    PubMed

    Carlip, S

    2007-07-13

    To explain black hole thermodynamics in quantum gravity, one must introduce constraints to ensure that a black hole is actually present. I show that for a large class of black holes, such "horizon constraints" allow the use of conformal field theory techniques to compute the density of states, reproducing the Bekenstein-Hawking entropy in a nearly model-independent manner. One standard string theory approach to black hole entropy arises as a special case, lending support to the claim that the mechanism may be "universal." I argue that the relevant degrees of freedom are Goldstone-boson-like excitations arising from the weak breaking of symmetry by the constraints. PMID:17678209

  20. CONSTRAINT EFFECT IN FRACTURE WHAT IS IT

    SciTech Connect

    Lam, P; Prof. Yuh J. Chao, P

    2008-10-29

    The meaning of the phrase 'constraint effect in fracture' has changed in the past two decades from 'contained plasticity' to a broader description of 'dependence of fracture toughness value on geometry of test specimen or structure'. This paper will first elucidate the fundamental mechanics reasons for the apparent 'constraint effects in fracture', followed by outlining a straightforward approach to overcoming this problem in both brittle (elastic) and ductile (elastic-plastic) fracture. It is concluded by discussing the major difference in constraint effect on fracture event in elastic and elastic-plastic materials.

  1. Black hole thermodynamics from Euclidean horizon constraints.

    PubMed

    Carlip, S

    2007-07-13

    To explain black hole thermodynamics in quantum gravity, one must introduce constraints to ensure that a black hole is actually present. I show that for a large class of black holes, such "horizon constraints" allow the use of conformal field theory techniques to compute the density of states, reproducing the Bekenstein-Hawking entropy in a nearly model-independent manner. One standard string theory approach to black hole entropy arises as a special case, lending support to the claim that the mechanism may be "universal." I argue that the relevant degrees of freedom are Goldstone-boson-like excitations arising from the weak breaking of symmetry by the constraints.

  2. The inevitability of genetic enhancement technologies.

    PubMed

    Baylis, Francoise; Robert, Jason Scott

    2004-01-01

    We outline a number of ethical objections to genetic technologies aimed at enhancing human capacities and traits. We then argue that, despite the persuasiveness of some of these objections, they are insufficient to stop the development and use of genetic enhancement technologies. We contend that the inevitability of the technologies results from a particular guiding worldview of humans as masters of the human evolutionary future, and conclude that recognising this worldview points to new directions for ethical thinking about genetic enhancement technologies. PMID:15168695

  3. Animal Science. Instructor Guide [and] Student Reference. Volume 28, Number 3 [and] Volume 28, Number 4.

    ERIC Educational Resources Information Center

    Baker, Andy; And Others

    This instructor guide and the corresponding student reference contain 4 units that include 30 lessons for a course in animal science for 11th- and 12th-grade agriculture science students. The units cover nutrition, genetics, reproduction, and animal health. The instructor's guide contains the following: objectives, competencies, motivational…

  4. EERE Peer Review Guide

    SciTech Connect

    2009-01-18

    The primary purpose of this guide is to provide managers and staff guidance in establishing formal in-progress peer review that provides intellectually fair expert evaluation of EERE RD3 and supporting business administration programs, both retrospective and prospective.

  5. Operator Certification Study Guide.

    ERIC Educational Resources Information Center

    American Water Works Association, Denver, CO.

    This study guide contains typical questions and answers that all levels of water treatment plant operators might expect to find on a certification examination. The manual covers the basic sciences, treatment techniques, testing procedures, and federal legislation. (Author/SB)

  6. Guided Inquiry Laboratory.

    ERIC Educational Resources Information Center

    Allen, J. B.; And Others

    1986-01-01

    Advocates the use of discovery or guided inquiry experiments for developing critical thinking in problem solving. Provides a stepwise method for creating inquiry experiments and provides an example by comparing the two methods for a freezing point experiment. (JM)

  7. The Saturn Educator Guide

    NASA Astrophysics Data System (ADS)

    Morrow, C. A.; Throop, H. B.

    1998-09-01

    NASA's Cassini Mission to Saturn is the most ambitious deep space mission ever. Its 4-year scientific tour of Saturn, its majestic rings, and its 18 presently known moons will reveal new beauty, richness and insights on behalf of all humankind. This presentation introduces the inquiry-based lessons from the innovative Saturn Educator Guide, appropriate for grades 5-8. The Guide is the product of a collaborative venture among teachers, scientists, engineers, and education researchers. The Guide offers opportunities to explore Saturn as a system, and the Cassini robotic spacecraft as an extension of human senses. There are also unique lessons on the history of science, science as a human endeavor, and science in social and personal perspectives. The Guide highlights the interconnections between Saturn and other areas of human endeavor (art, language, history and mythology). This distinctive blend will enable a grander diversity of learners to share and benefit from the excitement of Cassini mission discoveries.

  8. Low turbulence rod guide

    SciTech Connect

    Olinger, E.L.

    1992-05-26

    This patent describes an improved sucker rod guide for fixedly engaging around a sucker rod at a selected location along the length of the rod. It comprises a substantially cylindrical polymeric body having a longitudinal axis, a terminal end substantially continually tapered to the rod, a radially-inward surface and a radially outward surface, the radially inward surface of the body adjacent to and in tripping engagement with the rod when the rod guide is fixedly engaged around the rod; and a plurality of substantially continuous, longitudinal vanes carried by the body, a vane having a selected length and width, and longitudinally disposed along the radially outward surface of the guide body, extending radially away from the guide body and having a radially outside wear surface.

  9. EPA QUICK REFERENCE GUIDES

    EPA Science Inventory

    EPA Quick Reference Guides are compilations of information on chemical and biological terrorist agents. The information is presented in consistent format and includes agent characteristics, release scenarios, health and safety data, real-time field detection, effect levels, samp...

  10. Guide to Insulating Sheathing

    SciTech Connect

    2007-10-11

    This guide examines new methods of enclosure designs that provide high thermal performance and long-term durability but also take opportunities to reduce material use, simplify or integrate systems and details, and potentially reduce overall initial costs of construction.

  11. Wind Energy Teachers Guide

    SciTech Connect

    anon.

    2003-01-01

    This guide, created by the American Wind Association, with support from the U.S. Department of Energy, is a learning tool about wind energy targeted toward grades K-12. The guide provides teacher information, ideas for sparking children's and students' interest, suggestions for activities to undertake in and outside the classroom, and research tools for both teachers and students. Also included is an additional resources section.

  12. VOLTTRON: User Guide

    SciTech Connect

    Lutes, Robert G.; Katipamula, Srinivas; Akyol, Bora A.; Tenney, Nathan D.; Haack, Jereme N.; Monson, Kyle E.; Carpenter, Brandon J.

    2014-04-24

    This document is a user guide for the deployment of the Transactional Network platform and agent/application development within the VOLTTRON. The intent of this user guide is to provide a description of the functionality of the Transactional Network Platform. This document describes how to deploy the platform, including installation, use, guidance, and limitations. It also describes how additional features can be added to enhance its current functionality.

  13. Guide for a typewriter

    NASA Technical Reports Server (NTRS)

    Dubois, R. D.; Pinson, G. T. (Inventor)

    1976-01-01

    The invention relates to accessories for typewriters, and more particularly to an improved guide for use in aligning a sheet of paper preparatory to an application of typed indicia to selected spaces. The device includes an aligning plate pivotally mounted on a line guide having formed therein a plurality of aligned apertures. The plate is so positioned that an aperture is positioned immediately above a target area for a type slug so that a slug will imprint a character in selected spaces.

  14. Security guide for subcontractors

    SciTech Connect

    Adams, R.C.

    1991-01-01

    This security guide of the Department of Energy covers contractor and subcontractor access to DOE and Mound facilities. The topics of the security guide include responsibilities, physical barriers, personnel identification system, personnel and vehicular access controls, classified document control, protecting classified matter in use, storing classified matter repository combinations, violations, security education clearance terminations, security infractions, classified information nondisclosure agreement, personnel security clearances, visitor control, travel to communist-controlled or sensitive countries, shipment security, and surreptitious listening devices.

  15. Career Education Resource Guide for Biology. Working Draft.

    ERIC Educational Resources Information Center

    Louisiana State Dept. of Education, Baton Rouge.

    The resource guide integrates learning activities in biological science with an exploration of careers in biology or related fields. The materials are divided into seven units: tools of the scientist, basis for life, diversity (protists, plants, animals), structure and function, continuity (reproduction, development, and genetics), evolution, and…

  16. Control system design guide

    SciTech Connect

    Sellers, David; Friedman, Hannah; Haasl, Tudi; Bourassa, Norman; Piette, Mary Ann

    2003-05-01

    The ''Control System Design Guide'' (Design Guide) provides methods and recommendations for the control system design process and control point selection and installation. Control systems are often the most problematic system in a building. A good design process that takes into account maintenance, operation, and commissioning can lead to a smoothly operating and efficient building. To this end, the Design Guide provides a toolbox of templates for improving control system design and specification. HVAC designers are the primary audience for the Design Guide. The control design process it presents will help produce well-designed control systems that achieve efficient and robust operation. The spreadsheet examples for control valve schedules, damper schedules, and points lists can streamline the use of the control system design concepts set forth in the Design Guide by providing convenient starting points from which designers can build. Although each reader brings their own unique questions to the text, the Design Guide contains information that designers, commissioning providers, operators, and owners will find useful.

  17. Radiological design guide

    SciTech Connect

    Evans, R.A.

    1994-08-16

    The purpose of this design guide is to provide radiological safety requirements, standards, and information necessary for designing facilities that will operate without unacceptable risk to personnel, the public, or the environment as required by the US Department of Energy (DOE). This design guide, together with WHC-CM-4-29, Nuclear Criticality Safety, WHC-CM-4-46, Nonreactor Facility Safety Analysis, and WHC-CM-7-5, Environmental Compliance, covers the radiation safety design requirements at Westinghouse Hanford Company (WHC). This design guide applies to the design of all new facilities. The WHC organization with line responsibility for design shall determine to what extent this design guide shall apply to the modifications to existing facilities. In making this determination, consideration shall include a cost versus benefit study. Specifically, facilities that store, handle, or process radioactive materials will be covered. This design guide replaces WHC-CM-4-9 and is designated a living document. This design guide is intended for design purposes only. Design criteria are different from operational criteria and often more stringent. Criteria that might be acceptable for operations might not be adequate for design.

  18. Exploring evolutionary constraints is a task for an integrative evolutionary biology.

    PubMed

    Brakefield, P M; Roskam, J C

    2006-12-01

    Judging by the volume of writings about evolutionary constraints, they are an important topic in evolutionary biology. However, their involvement in shaping patterns of evolutionary change from morphological stasis to adaptive radiation remains contentious. This is at least in part because of the paucity of robust analyses of potential examples of constraints, whether of a more absolute or a relative nature. Here, we argue that what is needed to explore the type of constraints and bias on evolutionary change that may emerge from the way in which phenotypic variation is generated is an integrative approach applied to systems that can be tackled at different levels of biological organization. This is illustrated using research on the evolution of patterns in butterfly wing eyespots that has applied a combination of evolutionary genetics and evo-devo to an emerging model species with the beginnings of a comparative approach to describe patterns of variability among the extant taxa of two species-rich genera. PMID:17109328

  19. Exploring evolutionary constraints is a task for an integrative evolutionary biology.

    PubMed

    Brakefield, P M; Roskam, J C

    2006-12-01

    Judging by the volume of writings about evolutionary constraints, they are an important topic in evolutionary biology. However, their involvement in shaping patterns of evolutionary change from morphological stasis to adaptive radiation remains contentious. This is at least in part because of the paucity of robust analyses of potential examples of constraints, whether of a more absolute or a relative nature. Here, we argue that what is needed to explore the type of constraints and bias on evolutionary change that may emerge from the way in which phenotypic variation is generated is an integrative approach applied to systems that can be tackled at different levels of biological organization. This is illustrated using research on the evolution of patterns in butterfly wing eyespots that has applied a combination of evolutionary genetics and evo-devo to an emerging model species with the beginnings of a comparative approach to describe patterns of variability among the extant taxa of two species-rich genera.

  20. Planck 2015 constraints on neutrino physics

    NASA Astrophysics Data System (ADS)

    Lattanzi, Massimiliano

    2016-05-01

    Anisotropies of the cosmic microwave background radiation represent a powerful probe of neutrino physics, complementary to laboratory experiments. Here I review constraints on neutrino properties from the recent 2015 data from the Planck satellite.

  1. Constraint-based Attribute and Interval Planning

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari; Frank, Jeremy

    2013-01-01

    In this paper we describe Constraint-based Attribute and Interval Planning (CAIP), a paradigm for representing and reasoning about plans. The paradigm enables the description of planning domains with time, resources, concurrent activities, mutual exclusions among sets of activities, disjunctive preconditions and conditional effects. We provide a theoretical foundation for the paradigm, based on temporal intervals and attributes. We then show how the plans are naturally expressed by networks of constraints, and show that the process of planning maps directly to dynamic constraint reasoning. In addition, we de ne compatibilities, a compact mechanism for describing planning domains. We describe how this framework can incorporate the use of constraint reasoning technology to improve planning. Finally, we describe EUROPA, an implementation of the CAIP framework.

  2. New cosmological constraints on primordial black holes

    SciTech Connect

    Carr, B. J.; Kohri, Kazunori; Sendouda, Yuuiti; Yokoyama, Jun'ichi

    2010-05-15

    We update the constraints on the fraction of the Universe going into primordial black holes in the mass range 10{sup 9}-10{sup 17} g associated with the effects of their evaporations on big bang nucleosynthesis and the extragalactic photon background. We include for the first time all the effects of quark and gluon emission by black holes on these constraints and account for the latest observational developments. We then discuss the other constraints in this mass range and show that these are weaker than the nucleosynthesis and photon background limits, apart from a small range 10{sup 13}-10{sup 14} g, where the damping of cosmic microwave background anisotropies dominates. Finally we review the gravitational and astrophysical effects of nonevaporating primordial black holes, updating constraints over the broader mass range 1-10{sup 50} g.

  3. Biological constraints do not entail cognitive closure.

    PubMed

    Vlerick, Michael

    2014-12-01

    From the premise that our biology imposes cognitive constraints on our epistemic activities, a series of prominent authors--most notably Fodor, Chomsky and McGinn--have argued that we are cognitively closed to certain aspects and properties of the world. Cognitive constraints, they argue, entail cognitive closure. I argue that this is not the case. More precisely, I detect two unwarranted conflations at the core of arguments deriving closure from constraints. The first is a conflation of what I will refer to as 'representation' and 'object of representation'. The second confuses the cognitive scope of the assisted mind for that of the unassisted mind. Cognitive closure, I conclude, cannot be established from pointing out the (uncontroversial) existence of cognitive constraints.

  4. Genetic haemochromatosis.

    PubMed

    Rosalki, S B

    2002-10-01

    Genetic haemochromatosis is an autosomal recessive inherited disorder of iron metabolism due to mutation of the HFE gene. In homozygotes (1 in 300 of the UK population), this results in excessive iron absorption from the gut and its deposition in major body organs. This may give rise to fatigue, arthritis, cardiac failure, diabetes mellitus, hepatic cirrhosis or skin pigmentation, occurring predominantly in males over 50 years of age. Identification uses measurement of serum iron, iron-binding capacity (or transferrin) and ferritin, together with initial or confirmatory genetic DNA studies.

  5. Marketing and Society. Study Guide.

    ERIC Educational Resources Information Center

    Welsh, Robert S.; Blake, Rowland S.

    This self-instructional study guide is part of the materials for a college-level programmed course entitled "Marketing and Society." The study guide is intended for use by students in conjunction with a related textbook, a workbook, a review guide, and a series of instructional tape casettes. The study guide contains a brief introductory section…

  6. Knowledge, Attitudes, and Practice Regarding Genetic Testing and Genetic Counselors in Jordan: A Population-Based Survey.

    PubMed

    Ahram, Mamoun; Soubani, Majd; Abu Salem, Lana; Saker, Haneen; Ahmad, Muayyad

    2015-12-01

    Genetic testing has a potential in the prevention of genetic diseases, particularly in communities with high rates of consanguineous marriage. Therefore, knowledge, practice, and attitudes of the public in Jordan regarding genetic testing were investigated. Individuals (N = 3,196) were questioned about the concepts of genetic testing and genetic counselors, if they underwent any genetic tests, the type of test, the method of consenting to the test, as well as their level of satisfaction with the privacy of the genetic testing service. The likelihood of pursuing predictive genetic testing for cancer was also investigated. Although almost 70 % of respondents knew the term "genetic testing," only 18 % had undergone genetic testing, primarily the mandatory premarital test. In addition, there was a lack of general knowledge about genetic counselors. Many of those who had genetic testing (45 %) indicated they did not go through a consent process, and a lack of consent was significantly related to dissatisfaction with the privacy of the service. Approximately 55 % of respondents indicated they would potentially pursue predictive genetic testing for cancer. Going for routine health checkups was not significantly correlated with either actual or potential uptake of genetic testing, suggesting health care providers do not play an influential role in patients' testing decisions. Our results show a gap between the knowledge and uptake of genetic testing and may help to guide the design of effective strategies to initiate successful genetic counseling and testing services.

  7. Astronomical Insights into Dark Matter Particle Constraints

    NASA Astrophysics Data System (ADS)

    Dawson, William; Simon, Joshua D.; Read, Justin; Bullock, James; Keeton, Charles R.; Treu, Tommaso

    2016-01-01

    Intriguing constraints on key dark matter properties have been made through diverse astronomical measurements and experiments, not limited to the clustering of Lyman-alpha forest observations, the structure and energetics of the Bullet Cluster, the kinematics and dynamics of dwarf galaxies, statistics of strong gravitational lensing systems, and so on. We present a synthesis of the diversity of such observations, and discuss the relationship between the types of dark matter particle constraints they achieve.

  8. Causality constraints in conformal field theory

    DOE PAGES

    Hartman, Thomas; Jain, Sachin; Kundu, Sandipan

    2016-05-17

    Causality places nontrivial constraints on QFT in Lorentzian signature, for example fixing the signs of certain terms in the low energy Lagrangian. In d dimensional conformal field theory, we show how such constraints are encoded in crossing symmetry of Euclidean correlators, and derive analogous constraints directly from the conformal bootstrap (analytically). The bootstrap setup is a Lorentzian four-point function corresponding to propagation through a shockwave. Crossing symmetry fixes the signs of certain log terms that appear in the conformal block expansion, which constrains the interactions of low-lying operators. As an application, we use the bootstrap to rederive the well knownmore » sign constraint on the (Φ)4 coupling in effective field theory, from a dual CFT. We also find constraints on theories with higher spin conserved currents. As a result, our analysis is restricted to scalar correlators, but we argue that similar methods should also impose nontrivial constraints on the interactions of spinning operators« less

  9. Genetic Disorders

    MedlinePlus

    ... of pregnancy loss. How do I know which tests to have? Your health care provider or a genetic counselor can discuss all of the testing options with you and help you decide based on your individual risk factors. Do I have to have these tests? Whether you want to be tested is a ...

  10. Genetic Recombination

    ERIC Educational Resources Information Center

    Whitehouse, H. L. K.

    1973-01-01

    Discusses the mechanisms of genetic recombination with particular emphasis on the study of the fungus Sordaria brevicollis. The study of recombination is facilitated by the use of mutants of this fungus in which the color of the ascospores is affected. (JR)

  11. Selection and constraint underlie irreversibility of tooth loss in cypriniform fishes

    PubMed Central

    Aigler, Sharon R.; Jandzik, David; Hatta, Kohei; Uesugi, Kentaro; Stock, David W.

    2014-01-01

    The apparent irreversibility of the loss of complex traits in evolution (Dollo’s Law) has been explained either by constraints on generating the lost traits or the complexity of selection required for their return. Distinguishing between these explanations is challenging, however, and little is known about the specific nature of potential constraints. We investigated the mechanisms underlying the irreversibility of trait loss using reduction of dentition in cypriniform fishes, a lineage that includes the zebrafish (Danio rerio) as a model. Teeth were lost from the mouth and upper pharynx in this group at least 50 million y ago and retained only in the lower pharynx. We identified regional loss of expression of the Ectodysplasin (Eda) signaling ligand as a likely cause of dentition reduction. In addition, we found that overexpression of this gene in the zebrafish is sufficient to restore teeth to the upper pharynx but not to the mouth. Because both regions are competent to respond to Eda signaling with transcriptional output, the likely constraint on the reappearance of oral teeth is the alteration of multiple genetic pathways required for tooth development. The upper pharyngeal teeth are fully formed, but do not exhibit the ancestral relationship to other pharyngeal structures, suggesting that they would not be favored by selection. Our results illustrate an underlying commonality between constraint and selection as explanations for the irreversibility of trait loss; multiple genetic changes would be required to restore teeth themselves to the oral region and optimally functioning ones to the upper pharynx. PMID:24821783

  12. Competition as a source of constraint on life history evolution in natural populations

    PubMed Central

    Wilson, A J

    2014-01-01

    Competition among individuals is central to our understanding of ecology and population dynamics. However, it could also have major implications for the evolution of resource-dependent life history traits (for example, growth, fecundity) that are important determinants of fitness in natural populations. This is because when competition occurs, the phenotype of each individual will be causally influenced by the phenotypes, and so the genotypes, of competitors. Theory tells us that indirect genetic effects arising from competitive interactions will give rise to the phenomenon of ‘evolutionary environmental deterioration', and act as a source of evolutionary constraint on resource-dependent traits under natural selection. However, just how important this constraint is remains an unanswered question. This article seeks to stimulate empirical research in this area, first highlighting some patterns emerging from life history studies that are consistent with a competition-based model of evolutionary constraint, before describing several quantitative modelling strategies that could be usefully applied. A recurrent theme is that rigorous quantification of a competition's impact on life history evolution will require an understanding of the causal pathways and behavioural processes by which genetic (co)variance structures arise. Knowledge of the G-matrix among life history traits is not, in and of itself, sufficient to identify the constraints caused by competition. PMID:23443060

  13. Competition as a source of constraint on life history evolution in natural populations.

    PubMed

    Wilson, A J

    2014-01-01

    Competition among individuals is central to our understanding of ecology and population dynamics. However, it could also have major implications for the evolution of resource-dependent life history traits (for example, growth, fecundity) that are important determinants of fitness in natural populations. This is because when competition occurs, the phenotype of each individual will be causally influenced by the phenotypes, and so the genotypes, of competitors. Theory tells us that indirect genetic effects arising from competitive interactions will give rise to the phenomenon of 'evolutionary environmental deterioration', and act as a source of evolutionary constraint on resource-dependent traits under natural selection. However, just how important this constraint is remains an unanswered question. This article seeks to stimulate empirical research in this area, first highlighting some patterns emerging from life history studies that are consistent with a competition-based model of evolutionary constraint, before describing several quantitative modelling strategies that could be usefully applied. A recurrent theme is that rigorous quantification of a competition's impact on life history evolution will require an understanding of the causal pathways and behavioural processes by which genetic (co)variance structures arise. Knowledge of the G-matrix among life history traits is not, in and of itself, sufficient to identify the constraints caused by competition.

  14. The dimensionality of genetic variation for wing shape in Drosophila melanogaster.

    PubMed

    Mezey, Jason G; Houle, David

    2005-05-01

    Absolute constraints are limitations on genetic variation that preclude evolutionary change in some aspect of the phenotype. Absolute constraints may reflect complete absence of variation, lack of genetic variation that extends the range of phenotypes beyond some limit, or lack of additive genetic variation. This last type of absolute constraint is bidirectional, because the mean cannot evolve to be larger or smaller. Most traits do possess genetic variation, so bidirectional absolute constraints are most likely to be detected in a multivariate context, where they would reflect combinations of traits, or dimensions in phenotype space that cannot evolve. A bidirectional absolute constraint will cause the additive genetic covariance matrix (G) to have a rank less than the number of traits studied. In this study, we estimate the rank of the G-matrix for 20 aspects of wing shape in Drosophila melanogaster. Our best estimates of matrix rank are 20 in both sexes. Lower 95% confidence intervals of rank are 17 for females and 18 for males. We therefore find little evidence of bidirectional absolute constraints. We discuss the importance of this result for resolving the relative roles of selection and drift processes versus constraints in the evolution of wing shape in Drosophila.

  15. Constraint-Muse: A Soft-Constraint Based System for Music Therapy

    NASA Astrophysics Data System (ADS)

    Hölzl, Matthias; Denker, Grit; Meier, Max; Wirsing, Martin

    Monoidal soft constraints are a versatile formalism for specifying and solving multi-criteria optimization problems with dynamically changing user preferences. We have developed a prototype tool for interactive music creation, called Constraint Muse, that uses monoidal soft constraints to ensure that a dynamically generated melody harmonizes with input from other sources. Constraint Muse provides an easy to use interface based on Nintendo Wii controllers and is intended to be used in music therapy for people with Parkinson’s disease and for children with high-functioning autism or Asperger’s syndrome.

  16. Imposing Constraints from the Source Tree on ITG Constraints for SMT

    NASA Astrophysics Data System (ADS)

    Yamamoto, Hirofumi; Okuma, Hideo; Sumita, Eiichiro

    In the current statistical machine translation (SMT), erroneous word reordering is one of the most serious problems. To resolve this problem, many word-reordering constraint techniques have been proposed. Inversion transduction grammar (ITG) is one of these constraints. In ITG constraints, target-side word order is obtained by rotating nodes of the source-side binary tree. In these node rotations, the source binary tree instance is not considered. Therefore, stronger constraints for word reordering can be obtained by imposing further constraints derived from the source tree on the ITG constraints. For example, for the source word sequence { a b c d }, ITG constraints allow a total of twenty-two target word orderings. However, when the source binary tree instance ((a b) (c d)) is given, our proposed “imposing source tree on ITG” (IST-ITG) constraints allow only eight word orderings. The reduction in the number of word-order permutations by our proposed stronger constraints efficiently suppresses erroneous word orderings. In our experiments with IST-ITG using the NIST MT08 English-to-Chinese translation track's data, the proposed method resulted in a 1.8-points improvement in character BLEU-4 (35.2 to 37.0) and a 6.2% lower CER (74.1 to 67.9%) compared with our baseline condition.

  17. Cancer Genetics Services Directory

    MedlinePlus

    ... Overview–for health professionals Research NCI Cancer Genetics Services Directory This directory lists professionals who provide services related to cancer genetics (cancer risk assessment, genetic ...

  18. Genetic algorithms and supernovae type Ia analysis

    SciTech Connect

    Bogdanos, Charalampos; Nesseris, Savvas E-mail: nesseris@nbi.dk

    2009-05-15

    We introduce genetic algorithms as a means to analyze supernovae type Ia data and extract model-independent constraints on the evolution of the Dark Energy equation of state w(z) {identical_to} P{sub DE}/{rho}{sub DE}. Specifically, we will give a brief introduction to the genetic algorithms along with some simple examples to illustrate their advantages and finally we will apply them to the supernovae type Ia data. We find that genetic algorithms can lead to results in line with already established parametric and non-parametric reconstruction methods and could be used as a complementary way of treating SNIa data. As a non-parametric method, genetic algorithms provide a model-independent way to analyze data and can minimize bias due to premature choice of a dark energy model.

  19. Sucker rod guide

    SciTech Connect

    Edwards, B.J.; Starks, J.A.

    1989-08-22

    This patent describes a sucker rod guide for mounting on a sucker rod and spacing the sucker rod from the tubing in an oil well. The guide comprising a generally cylindrically-shaped, extruded, ultra-high density polyethylene body having a substantially smooth outside surface; a longitudinal bore provided centrally of the body. The bore having a smaller diameter than the diameter of the sucker rod; a plurality of grooves provided in circumferential relationship in the bore; and a tapered slot extending longitudinally through the body from the outside surface to the bore. The tapered slot further comprising a slot mouth located at the outside surface and a slot throat spaced from the slot mouth. The slot throat lying adjacent to the sucker rod bore and wherein the slot throat is wider than the slot mouth for mounting the sucker rod guide on the sucker rod.

  20. Materials Performance buyers guide

    SciTech Connect

    1996-11-01

    The MP Buyers Guide is an exclusive directory of manufacturers, suppliers, and consultants providing products and services for the prevention and control of corrosion. The Guide is divided into three primary directories: Company Directory, Product Directory, and Trade Name Directory. The Guide also contains a NACE Resource Directory. The index of products and services provides an extensive index of manufacturers, suppliers, and consultants, listed according to specific product categories. The index of suppliers, manufacturers, and consultants contains a detailed alphabetical list of more than 900 manufacturers, suppliers, and consultants providing products and services for corrosion prevention and control. Included are each company`s name, address, contact name, phone number, fax number, email address, branch offices, and a brief description of their products and services. The index of product names is an alphabetical listing of product trade names cross-referenced to the manufacturer, supplier, or consultant.

  1. Genetic Algorithms for Digital Quantum Simulations

    NASA Astrophysics Data System (ADS)

    Las Heras, U.; Alvarez-Rodriguez, U.; Solano, E.; Sanz, M.

    2016-06-01

    We propose genetic algorithms, which are robust optimization techniques inspired by natural selection, to enhance the versatility of digital quantum simulations. In this sense, we show that genetic algorithms can be employed to increase the fidelity and optimize the resource requirements of digital quantum simulation protocols while adapting naturally to the experimental constraints. Furthermore, this method allows us to reduce not only digital errors but also experimental errors in quantum gates. Indeed, by adding ancillary qubits, we design a modular gate made out of imperfect gates, whose fidelity is larger than the fidelity of any of the constituent gates. Finally, we prove that the proposed modular gates are resilient against different gate errors.

  2. Constraint satisfaction and optimization for space station short-term mission planning based on an iterative conflict-repair method

    NASA Astrophysics Data System (ADS)

    Bu, Hui-Jiao; Zhang, Jin; Luo, Ya-Zhong

    2016-10-01

    This article studies the optimization of space station short-term mission planning (STMP) problems. The domain knowledge including description and the concept definitions of the STMP problem are presented, an STMP constraint satisfaction model is developed, and then an iterative conflict-repair method with the resolving strategies is proposed to satisfy complicated constraints. A genetic algorithm (GA) is adopted to optimize the STMP problem. The proposed approach is evaluated using a test case with 15 missions, 13 devices and three astronauts. The results show that the established STMP constraint satisfaction model is effective, and the iterative conflict-repair method can make the plan satisfy all constraints considered and can effectively improve the optimization performance of the GA.

  3. Genetic testing, genetic medicine, and managed care.

    PubMed

    Rothstein, M A; Hoffman, S

    1999-01-01

    As modern human genetics moves from the research setting to the clinical setting, it will encounter the managed care system. Issues of cost, access, and quality of care will affect the availability and nature of genetic testing, genetic counseling, and genetic therapies. This Article will explore such issues as professional education, coverage of genetic services, privacy and confidentiality, and liability. It will conclude with a series of recommendations for the practice of genetic medicine in the age of managed care.

  4. Synthetic guide star generation

    DOEpatents

    Payne, Stephen A.; Page, Ralph H.; Ebbers, Christopher A.; Beach, Raymond J.

    2004-03-09

    A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

  5. Synthetic guide star generation

    DOEpatents

    Payne, Stephen A [Castro Valley, CA; Page, Ralph H [Castro Valley, CA; Ebbers, Christopher A [Livermore, CA; Beach, Raymond J [Livermore, CA

    2008-06-10

    A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

  6. Manifold tool guide

    DOEpatents

    Djordjevic, A.

    1982-07-08

    A tool guide that makes possible the insertion of cleaning and/or inspection tools into a manifold pipe that will dislocate and extract the accumulated sediment in such manifold pipes. The tool guide basically comprises a right angled tube (or other angled tube as required) which can be inserted in a large tube and locked into a radially extending cross pipe by adjustable spacer rods and a spring-loaded cone, whereby appropriate cleaning tools can be inserted into to cross pipe for cleaning, inspection, etc.

  7. Manifold tool guide

    DOEpatents

    Djordjevic, A.

    1983-12-27

    A tool guide is described that makes possible the insertion of cleaning and/or inspection tools into a manifold pipe that will dislocate and extract the accumulated sediment in such manifold pipes. The tool guide basically comprises a right angled tube (or other angled tube as required) which can be inserted in a large tube and locked into a radially extending cross pipe by adjustable spacer rods and a spring-loaded cone, whereby appropriate cleaning tools can be inserted into the cross pipe for cleaning, inspection, etc. 3 figs.

  8. Manifold tool guide

    DOEpatents

    Djordjevic, Aleksandar

    1983-12-27

    A tool guide that makes possible the insertion of cleaning and/or inspection tools into a manifold pipe that will dislocate and extract the accumulated sediment in such manifold pipes. The tool guide basically comprises a right angled tube (or other angled tube as required) which can be inserted in a large tube and locked into a radially extending cross pipe by adjustable spacer rods and a spring-loaded cone, whereby appropriate cleaning tools can be inserted into to cross pipe for cleaning, inspection, etc.

  9. Seismic Safety Guide

    SciTech Connect

    Eagling, D.G.

    1983-09-01

    This guide provides managers with practical guidelines for administering a comprehensive earthquake safety program. The Guide is comprehensive with respect to earthquakes in that it covers the most important aspects of natural hazards, site planning, evaluation and rehabilitation of existing buildings, design of new facilities, operational safety, emergency planning, special considerations related to shielding blocks, non-structural elements, lifelines, fire protection and emergency facilities. Management of risk and liabilities is also covered. Nuclear facilities per se are not dealt with specifically. The principles covered also apply generally to nuclear facilities but the design and construction of such structures are subject to special regulations and legal controls.

  10. Forces Associated with Nonlinear Nonholonomic Constraint Equations

    NASA Technical Reports Server (NTRS)

    Roithmayr, Carlos M.; Hodges, Dewey H.

    2010-01-01

    A concise method has been formulated for identifying a set of forces needed to constrain the behavior of a mechanical system, modeled as a set of particles and rigid bodies, when it is subject to motion constraints described by nonholonomic equations that are inherently nonlinear in velocity. An expression in vector form is obtained for each force; a direction is determined, together with the point of application. This result is a consequence of expressing constraint equations in terms of dot products of vectors rather than in the usual way, which is entirely in terms of scalars and matrices. The constraint forces in vector form are used together with two new analytical approaches for deriving equations governing motion of a system subject to such constraints. If constraint forces are of interest they can be brought into evidence in explicit dynamical equations by employing the well-known nonholonomic partial velocities associated with Kane's method; if they are not of interest, equations can be formed instead with the aid of vectors introduced here as nonholonomic partial accelerations. When the analyst requires only the latter, smaller set of equations, they can be formed directly; it is not necessary to expend the labor to form the former, larger set first and subsequently perform matrix multiplications.

  11. Diffusion Processes Satisfying a Conservation Law Constraint

    DOE PAGES

    Bakosi, J.; Ristorcelli, J. R.

    2014-03-04

    We investigate coupled stochastic differential equations governing N non-negative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires that a set of fluctuating variables be non-negative and (if appropriately normalized) sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the non-negativity and the unit-sum conservation law constraint are satisfied as the variables evolve in time. We investigate the consequencesmore » of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have diffusion terms that are coupled and nonlinear. The set of constraints developed enables the development of statistical representations of fluctuating variables satisfying a conservation law. We exemplify the results with the bivariate beta process and the multivariate Wright-Fisher, Dirichlet, and Lochner’s generalized Dirichlet processes.« less

  12. Diffusion Processes Satisfying a Conservation Law Constraint

    SciTech Connect

    Bakosi, J.; Ristorcelli, J. R.

    2014-03-04

    We investigate coupled stochastic differential equations governing N non-negative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires that a set of fluctuating variables be non-negative and (if appropriately normalized) sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the non-negativity and the unit-sum conservation law constraint are satisfied as the variables evolve in time. We investigate the consequences of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have diffusion terms that are coupled and nonlinear. The set of constraints developed enables the development of statistical representations of fluctuating variables satisfying a conservation law. We exemplify the results with the bivariate beta process and the multivariate Wright-Fisher, Dirichlet, and Lochner’s generalized Dirichlet processes.

  13. Reliable biological communication with realistic constraints.

    PubMed

    de Polavieja, Gonzalo G

    2004-12-01

    Communication in biological systems must deal with noise and metabolic or temporal constraints. We include these constraints into information theory to obtain the distributions of signal usage corresponding to a maximal rate of information transfer given any noise structure and any constraints. Generalized versions of the Boltzmann, Gaussian, or Poisson distributions are obtained for linear, quadratic and temporal constraints, respectively. These distributions are shown to imply that biological transformations must dedicate a larger output range to the more probable inputs and less to the outputs with higher noise and higher participation in the constraint. To show the general theory of reliable communication at work, we apply these results to biochemical and neuronal signaling. Noncooperative enzyme kinetics is shown to be suited for transfer of a high signal quality when the input distribution has a maximum at low concentrations while cooperative kinetics for near-Gaussian input statistics. Neuronal codes based on spike rates, spike times or bursts have to balance signal quality and cost-efficiency and at the network level imply sparseness and uncorrelation within the limits of noise, cost, and processing operations. PMID:15697405

  14. Two new constraints for the cumulant matrix

    SciTech Connect

    Ramos-Cordoba, Eloy; Salvador, Pedro; Matito, Eduard; Piris, Mario

    2014-12-21

    We suggest new strict constraints that the two-particle cumulant matrix should fulfill. The constraints are obtained from the decomposition of 〈S-^{sup 2}〉, previously developed in our laboratory, and the vanishing number of electrons shared by two non-interacting fragments. The conditions impose stringent constraints into the cumulant structure without any need to perform an orbital optimization procedure thus carrying very small or no computational effort. These constraints are tested on the series of Piris natural orbital functionals (PNOF), which are among the most accurate ones available in the literature. Interestingly, even though all PNOF cumulants ensure correct overall 〈S{sup ^2}〉 values, none of them is consistent with the local spin structure of systems that dissociate more than one pair of electrons. A careful analysis of the local spin components reveals the most important missing contributions in the cumulant expression thus suggesting a means to improve PNOF5. The constraints provide an inexpensive tool for the construction and testing of cumulant structures that complement previously known conditions such as the N-representability or the square of the total spin angular momentum, 〈S{sup ^2}〉.

  15. Pair Production Constraints on Superluminal Neutrinos Revisited

    SciTech Connect

    Brodsky, Stanley J.; Gardner, Susan; /Kentucky U.

    2012-02-16

    We revisit the pair creation constraint on superluminal neutrinos considered by Cohen and Glashow in order to clarify which types of superluminal models are constrained. We show that a model in which the superluminal neutrino is effectively light-like can evade the Cohen-Glashow constraint. In summary, any model for which the CG pair production process operates is excluded because such timelike neutrinos would not be detected by OPERA or other experiments. However, a superluminal neutrino which is effectively lightlike with fixed p{sup 2} can evade the Cohen-Glashow constraint because of energy-momentum conservation. The coincidence involved in explaining the SN1987A constraint certainly makes such a picture improbable - but it is still intrinsically possible. The lightlike model is appealing in that it does not violate Lorentz symmetry in particle interactions, although one would expect Hughes-Drever tests to turn up a violation eventually. Other evasions of the CG constraints are also possible; perhaps, e.g., the neutrino takes a 'short cut' through extra dimensions or suffers anomalous acceleration in matter. Irrespective of the OPERA result, Lorentz-violating interactions remain possible, and ongoing experimental investigation of such possibilities should continue.

  16. Human genetics

    SciTech Connect

    Carlson, E.A.

    1984-01-01

    This text provides full and balanced coverage of the concepts requisite for a thorough understanding of human genetics. Applications to both the individual and society are integrated throughout the lively and personal narrative, and the essential principles of heredity are clearly presented to prepare students for informed participation in public controversies. High-interest, controversial topics, including recombinant DNA technology, oncogenes, embryo transfer, environmental mutagens and carcinogens, IQ testing, and eugenics encourage understanding of important social issues.

  17. Clock gene evolution: seasonal timing, phylogenetic signal, or functional constraint?

    PubMed

    Krabbenhoft, Trevor J; Turner, Thomas F

    2014-01-01

    Genetic determinants of seasonal reproduction are not fully understood but may be important predictors of organism responses to climate change. We used a comparative approach to study the evolution of seasonal timing within a fish community in a natural common garden setting. We tested the hypothesis that allelic length variation in the PolyQ domain of a circadian rhythm gene, Clock1a, corresponded to interspecific differences in seasonal reproductive timing across 5 native and 1 introduced cyprinid fishes (n = 425 individuals) that co-occur in the Rio Grande, NM, USA. Most common allele lengths were longer in native species that initiated reproduction earlier (Spearman's r = -0.70, P = 0.23). Clock1a allele length exhibited strong phylogenetic signal and earlier spawners were evolutionarily derived. Aside from length variation in Clock1a, all other amino acids were identical across native species, suggesting functional constraint over evolutionary time. Interestingly, the endangered Rio Grande silvery minnow (Hybognathus amarus) exhibited less allelic variation in Clock1a and observed heterozygosity was 2- to 6-fold lower than the 5 other (nonimperiled) species. Reduced genetic variation in this functionally important gene may impede this species' capacity to respond to ongoing environmental change. PMID:24558102

  18. Host immune constraints on malaria transmission: insights from population biology of within-host parasites

    PubMed Central

    2013-01-01

    Background Plasmodium infections trigger complex immune reactions from their hosts against several life stages of the parasite, including gametocytes. These immune responses are highly variable, depending on age, genetics, and exposure history of the host as well as species and strain of parasite. Although the effects of host antibodies that act against gamete stages in the mosquito (due to uptake in the blood meal) are well documented, the effects of host immunity upon within-host gametocytes are not as well understood. This report consists of a theoretical population biology-based analysis to determine constraints that host immunity impose upon gametocyte population growth. The details of the mathematical models used for the analysis were guided by published reports of clinical and animal studies, incorporated plausible modalities of immune reactions to parasites, and were tailored to the life cycl es of the two most widespread human malaria pathogens, Plasmodium falciparum and Plasmodium vivax. Results For the same ability to bind and clear a target, the model simulations suggest that an antibody attacking immature gametocytes would tend to lower the overall density of transmissible mature gametocytes more than an antibody attacking the mature forms directly. Transmission of P. falciparum would be especially vulnerable to complete blocking by antibodies to its immature forms since its gametocytes take much longer to reach maturity than those of P. vivax. On the other hand, antibodies attacking the mature gametocytes directly would reduce the time the mature forms can linger in the host. Simulation results also suggest that varying the standard deviation in the time necessary for individual asexual parasites to develop and produce schizonts can affect the efficiency of production of transmissible gametocytes. Conclusions If mature gametocyte density determines the probability of transmission, both Plasmodium species, but especially P. falciparum, could bolster

  19. NMR Constraints Analyser: a web-server for the graphical analysis of NMR experimental constraints.

    PubMed

    Heller, Davide Martin; Giorgetti, Alejandro

    2010-07-01

    Nuclear magnetic resonance (NMR) spectroscopy together with X-ray crystallography, are the main techniques used for the determination of high-resolution 3D structures of biological molecules. The output of an NMR experiment includes a set of lower and upper limits for the distances (constraints) between pairs of atoms. If the number of constraints is high enough, there will be a finite number of possible conformations (models) of the macromolecule satisfying the data. Thus, the more constraints are measured, the better defined these structures will be. The availability of a user-friendly tool able to help in the analysis and interpretation of the number of experimental constraints per residue, is thus of valuable importance when assessing the levels of structure definition of NMR solved biological macromolecules, in particular, when high-quality structures are needed in techniques such as, computational biology approaches, site-directed mutagenesis experiments and/or drug design. Here, we present a free publicly available web-server, i.e. NMR Constraints Analyser, which is aimed at providing an automatic graphical analysis of the NMR experimental constraints atom by atom. The NMR Constraints Analyser server is available from the web-page http://molsim.sci.univr.it/constraint.

  20. The Role of Motivation, Perceived Constraints, and Constraint Negotiation Strategies in Students' Internship Selection Experience

    ERIC Educational Resources Information Center

    Batty, Kimberly A.

    2011-01-01

    The purpose of this study was to document the factors (i.e., motivation and perceived constraints) and processes (i.e., constraint negotiation) that influence students' selection of and satisfaction with their internship choice. The study was conducted using a quantitative approach, which included a focus group, a pilot study, and a…

  1. Genetic Testing (For Parents)

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Genetic Testing KidsHealth > For Parents > Genetic Testing Print A ... blood, skin, bone, or other tissue is needed. Genetic Testing During Pregnancy For genetic testing before birth, ...

  2. Cancer Genetics Services Directory

    MedlinePlus

    ... Services Directory Cancer Prevention Overview Research NCI Cancer Genetics Services Directory This directory lists professionals who provide services related to cancer genetics (cancer risk assessment, genetic counseling, genetic susceptibility testing, ...

  3. Straightness error evaluation of additional constraints

    NASA Astrophysics Data System (ADS)

    Pei, Ling; Wang, Shenghuai; Liu, Yong

    2011-05-01

    A new generation of Dimensional and Geometrical Product Specifications (GPS) and Verification standard system is based on both the Mathematical structure and the Metrology. To determine the eligibility of the product should be adapt to modern digital measuring instruments. But in mathematizating measurement when the geometric tolerance specifications has additional constraints requirement, such as straightness with an additional constraint, required to qualify the additional form requirements of the feature within the tolerance zone. Knowing how to close the geometrical specification to the functional specification will result in the correctness of measurement results. Adopting the methodology to evaluate by analyzing various forms including the ideal features and the extracted features and their combinations in an additional form constraint of the straightness in tolerance zone had been found correctly acceptance decision for products. The results show that different combinations of the various forms had affected acceptance on the product qualification and the appropriate forms matching can meet the additional form requirements for product features.

  4. Straightness error evaluation of additional constraints

    NASA Astrophysics Data System (ADS)

    Pei, Ling; Wang, Shenghuai; Liu, Yong

    2010-12-01

    A new generation of Dimensional and Geometrical Product Specifications (GPS) and Verification standard system is based on both the Mathematical structure and the Metrology. To determine the eligibility of the product should be adapt to modern digital measuring instruments. But in mathematizating measurement when the geometric tolerance specifications has additional constraints requirement, such as straightness with an additional constraint, required to qualify the additional form requirements of the feature within the tolerance zone. Knowing how to close the geometrical specification to the functional specification will result in the correctness of measurement results. Adopting the methodology to evaluate by analyzing various forms including the ideal features and the extracted features and their combinations in an additional form constraint of the straightness in tolerance zone had been found correctly acceptance decision for products. The results show that different combinations of the various forms had affected acceptance on the product qualification and the appropriate forms matching can meet the additional form requirements for product features.

  5. General constraints on the Viking biology investigation

    NASA Technical Reports Server (NTRS)

    Klein, H. P.

    1976-01-01

    The paper discusses some of the constraints pertaining to the Viking mission for detection of life on Mars, within which the Viking experiments were conceived, designed, and developed. The most important limitation to the entire study is the complete information about the nature of Mars, such as the chemical composition of the surface material of Mars and the exact identification of the constituents of that planet. Ways in which celestial mechanics places severe limitations on the Viking biology investigation are discussed. Major engineering constraints are examined relative to the accomodation of biology instrument inside the Viking lander and to the design of the instrument itself. Other constraints discussed concern the operational aspects of the mission and the testing program.

  6. Cognitive dissonance reduction as constraint satisfaction.

    PubMed

    Shultz, T R; Lepper, M R

    1996-04-01

    A constraint satisfaction neural network model (the consonance model) simulated data from the two major cognitive dissonance paradigms of insufficient justification and free choice. In several cases, the model fit the human data better than did cognitive dissonance theory. Superior fits were due to the inclusion of constraints that were not part of dissonance theory and to the increased precision inherent to this computational approach. Predictions generated by the model for a free choice between undesirable alternatives were confirmed in a new psychological experiment. The success of the consonance model underscores important, unforeseen similarities between what had been formerly regarded as the rather exotic process of dissonance reduction and a variety of other, more mundane psychological processes. Many of these processes can be understood as the progressive application of constraints supplied by beliefs and attitudes.

  7. Biological organisation as closure of constraints.

    PubMed

    Montévil, Maël; Mossio, Matteo

    2015-05-01

    We propose a conceptual and formal characterisation of biological organisation as a closure of constraints. We first establish a distinction between two causal regimes at work in biological systems: processes, which refer to the whole set of changes occurring in non-equilibrium open thermodynamic conditions; and constraints, those entities which, while acting upon the processes, exhibit some form of conservation (symmetry) at the relevant time scales. We then argue that, in biological systems, constraints realise closure, i.e. mutual dependence such that they both depend on and contribute to maintaining each other. With this characterisation in hand, we discuss how organisational closure can provide an operational tool for marking the boundaries between interacting biological systems. We conclude by focusing on the original conception of the relationship between stability and variation which emerges from this framework.

  8. Optimization of EB plant by constraint control

    SciTech Connect

    Hummel, H.K.; de Wit, G.B.C.; Maarleveld, A. )

    1991-03-01

    Optimum plant operation can often be achieved by means of constraint control instead of model- based on-line optimization. This is because optimum operation is seldom at the top of the hill but usually at the intersection of constraints. This article describes the development of a constraint control system for a plant producing ethylbenzene (EB) by the Mobil/Badger Ethylbenzene Process. Plant optimization can be defined as the maximization of a profit function describing the economics of the plant. This function contains terms with product values, feedstock prices and operational costs. Maximization of the profit function can be obtained by varying relevant degrees of freedom in the plant, such as a column operating pressure or a reactor temperature. These degrees of freedom can be varied within the available operating margins of the plant.

  9. Restricting query relaxation through user constraints

    SciTech Connect

    Gaasterland, T.

    1993-07-01

    This paper describes techniques to restrict and to heuristically control relaxation of deductive database queries. The process of query relaxation provides a user with a means to automatically identify new queries that are related to the user`s original query. However, for large databases, many relaxations may be possible. The methods to control and restrict the relaxation process introduced in this paper focus the relaxation process and make it more efficient. User restrictions over the data base domain may be expressed as user constraints. This paper describes how user constraints can restrict relaxed queries. Also, a set of heuristics based on cooperative answering techniques are presented for controlling the relaxation process. Finally, the interaction of the methods for relaxing queries, processing user constraints, and applying the heuristic rules is described.

  10. Inference-based constraint satisfaction supports explanation

    SciTech Connect

    Sqalli, M.H.; Freuder, E.C.

    1996-12-31

    Constraint satisfaction problems are typically solved using search, augmented by general purpose consistency inference methods. This paper proposes a paradigm shift in which inference is used as the primary problem solving method, and attention is focused on special purpose, domain specific inference methods. While we expect this approach to have computational advantages, we emphasize here the advantages of a solution method that is more congenial to human thought processes. Specifically we use inference-based constraint satisfaction to support explanations of the problem solving behavior that are considerably more meaningful than a trace of a search process would be. Logic puzzles are used as a case study. Inference-based constraint satisfaction proves surprisingly powerful and easily extensible in this domain. Problems drawn from commercial logic puzzle booklets are used for evaluation. Explanations are produced that compare well with the explanations provided by these booklets.

  11. Propagating Resource Constraints Using Mutual Exclusion Reasoning

    NASA Technical Reports Server (NTRS)

    Frank, Jeremy; Sanchez, Romeo; Do, Minh B.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    One of the most recent techniques for propagating resource constraints in Constraint Based scheduling is Energy Constraint. This technique focuses in precedence based scheduling, where precedence relations are taken into account rather than the absolute position of activities. Although, this particular technique proved to be efficient on discrete unary resources, it provides only loose bounds for jobs using discrete multi-capacity resources. In this paper we show how mutual exclusion reasoning can be used to propagate time bounds for activities using discrete resources. We show that our technique based on critical path analysis and mutex reasoning is just as effective on unary resources, and also shows that it is more effective on multi-capacity resources, through both examples and empirical study.

  12. Astrophysical Constraints of Dark Matter Properties

    NASA Astrophysics Data System (ADS)

    Moustakas, Leonidas A.; Abel, Tom; Brooks, Alyson; Buckley, Matthew; Bullock, James; Collins, Michelle; Cyr-Racine, Francis-Yan; Dawson, William; Drlica-Wagner, Alex; Gaskins, Jennifer; Kaplinghat, Manoj; Keeton, Charles R.; Kim, Stacy; Peter, Annika; Read, Justin; Simon, Joshua D.; Somerville, Rachel S.; Tollerud, Erik Jon; Treu, Tommaso; Wechsler, Risa H.

    2016-01-01

    The nature of the dark matter that fills the universe remains a profound puzzle in physics and astrophysics. Modern astronomical observations have the potential to produce constraints or measurements on properties of dark matter that may have real power for insights into its particle nature. The key lies with understanding what those constraints may be in a way that is interpretable for both the astronomical and particle physics communities, and establishing a community consensus of how diverse astronomical paths can use a common language. The AAS Special Session on the "Astrophysical constraints of dark matter properties" focuses on framing these questions with concrete proposals for astronomical dark matter metrics and potentially figures of merit, and through a series of presentations that serve as points of departure for discussion, ultimately to reach a community consensus that will be useful for current and future pursuits on this topic.

  13. The transmission interface constraint problem. Revision

    SciTech Connect

    Baldick, R.; Kahn, E.

    1994-10-01

    Electric power transmission systems exhibit a number of complex constraints on their operation and usage. When a network is subject to a constraint that limits the amount of power that can be moved from one region to another, there is said to be an interface limit. The power systems literature gives no general treatment of the engineering-economics of this ubiquitous phenomenon. Particular aspects of interface limits are typically discussed in sophisticated technical detail, but the general engineering-economic trade-offs involved in relieving interface constraints have not been systematically addressed. We approach this problem in the spirit of a heuristic model. Such models are quite valuable under current industry conditions because they delineate technical opportunities and choices in situations where there may be conflicting views among competing parties and regulatory authorities. We organize and enumerate the choices, clarify the practical conditions that dictate the optimum in particular cases, and help to motivate the final choices made by planners.

  14. Spacecraft Attitude Maneuver Planning Using Genetic Algorithms

    NASA Technical Reports Server (NTRS)

    Kornfeld, Richard P.

    2004-01-01

    A key enabling technology that leads to greater spacecraft autonomy is the capability to autonomously and optimally slew the spacecraft from and to different attitudes while operating under a number of celestial and dynamic constraints. The task of finding an attitude trajectory that meets all the constraints is a formidable one, in particular for orbiting or fly-by spacecraft where the constraints and initial and final conditions are of time-varying nature. This approach for attitude path planning makes full use of a priori constraint knowledge and is computationally tractable enough to be executed onboard a spacecraft. The approach is based on incorporating the constraints into a cost function and using a Genetic Algorithm to iteratively search for and optimize the solution. This results in a directed random search that explores a large part of the solution space while maintaining the knowledge of good solutions from iteration to iteration. A solution obtained this way may be used as is or as an initial solution to initialize additional deterministic optimization algorithms. A number of representative case examples for time-fixed and time-varying conditions yielded search times that are typically on the order of minutes, thus demonstrating the viability of this method. This approach is applicable to all deep space and planet Earth missions requiring greater spacecraft autonomy, and greatly facilitates navigation and science observation planning.

  15. MADS Users' Guide

    NASA Technical Reports Server (NTRS)

    Moerder, Daniel D.

    2014-01-01

    MADS (Minimization Assistant for Dynamical Systems) is a trajectory optimization code in which a user-specified performance measure is directly minimized, subject to constraints placed on a low-order discretization of user-supplied plant ordinary differential equations. This document describes the mathematical formulation of the set of trajectory optimization problems for which MADS is suitable, and describes the user interface. Usage examples are provided.

  16. The B-matrix harbors significant and sex-specific constraints on the evolution of multicharacter sexual dimorphism.

    PubMed

    Gosden, Thomas P; Shastri, Krishna-Lila; Innocenti, Paolo; Chenoweth, Stephen F

    2012-07-01

    The extent to which sexual dimorphism can evolve within a population depends on an interaction between sexually divergent selection and constraints imposed by a genetic architecture that is shared between males and females. The degree of constraint within a population is normally inferred from the intersexual genetic correlation, r(mf) . However, such bivariate correlations ignore the potential constraining effect of genetic covariances between other sexually coexpressed traits. Using the fruit fly Drosophila serrata, a species that exhibits mutual mate preference for blends of homologous contact pheromones, we tested the impact of between-sex between-trait genetic covariances using an extended version of the genetic variance-covariance matrix, G, that includes Lande's (1980) between-sex covariance matrix, B. We find that including B greatly reduces the degree to which male and female traits are predicted to diverge in the face of divergent phenotypic selection. However, the degree to which B alters the response to selection differs between the sexes. The overall rate of male trait evolution is predicted to decline, but its direction remains relatively unchanged, whereas the opposite is found for females. We emphasize the importance of considering the B-matrix in microevolutionary studies of constraint on the evolution of sexual dimorphism.

  17. Citizen's Guide to Pesticides.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Pesticide Programs.

    This guide provides suggestions on pest control and safety rules for pesticide use at home. Pest prevention may be possible by modification of pest habitat: removal of food and water sources, removal or destruction of pest shelter and breeding sites, and good horticultural practices that reduce plant stress. Nonchemical alternatives to pesticides…

  18. HAPPIER: Health Resource Guide.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg.

    Based on findings of Project HAPPIER surveys and intended as a resource for health care providers and educators who serve the migrant community, this guide describes over 375 instructional materials in the areas of dental health, disease control, fitness, health promotion, human growth and development, hypertension, maternal and child care, mental…

  19. Basic Pneumatics. Instructor's Guide.

    ERIC Educational Resources Information Center

    Fessehaye, Michael

    This instructor's guide is designed for use by industrial vocational teachers in teaching a course on basic pneumatics. Covered in the individual units are the following topics: an introduction to pneumatics (including the operation of a service station hoist); fundamentals and physical laws; air compressors (positive displacement compressors;…

  20. Barbering Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide presents the barbering program for technical institutes in Georgia. The general information section contains the following: purpose and objectives; program description, including admissions, typical job titles, and accreditation and certification; and curriculum model, including standard curriculum sequence and lists of courses.…

  1. Moving? A Relocation Guide.

    ERIC Educational Resources Information Center

    Rackliffe, Gary; Pearson, Nancy

    This guide answers questions for high school graduates moving away from home for the first time. The question and answer format begins with reasons for moving and offers ways of finding information about a new town before leaving, meeting people, and fighting homesickness and indecision. Practical advice is presented on money management and…

  2. Solar Curriculum Guides, 1980.

    ERIC Educational Resources Information Center

    Seward County Community Coll., Liberal, KS.

    This document contains an outline for a curriculum to train solar energy technicians in community colleges. The guide contains eight courses, each of which is divided into one to five modules. Modules, in turn, are divided into units, and units contain student handouts appropriate to the material. The following eight courses are included in this…

  3. GROWING SEEDS, TEACHER'S GUIDE.

    ERIC Educational Resources Information Center

    Elementary Science Study, Newton, MA.

    THIS TEACHER'S GUIDE IS DESIGNED FOR USE WITH AN ELEMENTARY SCIENCE STUDY UNIT, "GROWING SEEDS," IN WHICH SUCH BASIC SCIENCE SKILLS AND PROCESSES AS MEASUREMENT, OBSERVATION, AND HYPOTHESIS FORMATION ARE INTRODUCED THROUGH STUDENT ACTIVITIES INVOLVING SEEDS, GERMINATION, AND SEEDLING GROWTH. THE MATERIALS WERE DEVELOPED FOR USE IN ELEMENTARY…

  4. Elementary Science Resource Guide.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin. Div. of Curriculum Development.

    This guide for elementary teachers provides information on getting ideas into action, designing and implementing the right situation, ways in which to evaluate science process activities with students, and seven sample units. The units cover using the senses, magnets, forces, weather forecasting, classification of living things, and the physical…

  5. Appliance Servicing Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide presents the standard appliance servicing technician curriculum for technical institutes in Georgia. The general information section contains the following: purpose and objectives; program description, including admissions, typical job titles, and accreditation and certification; and curriculum model, including standard…

  6. Destination: Poland. Video Guide.

    ERIC Educational Resources Information Center

    Puchalski, Shirley; Legowski, Margaret

    This video guide was developed for teachers and students participating in the Peace Corps World Wise Schools program. The primary purpose of the study/video series is to enhance each class's correspondence with its Peace Corps Volunteer and help students gain a greater understanding of regions and cultures different from their own. The specific…

  7. Evolution. Teacher's Guide.

    ERIC Educational Resources Information Center

    Bershad, Carol

    This teacher's guide was developed to assist teachers in the use of multimedia resources for the Public Broadcasting System (PBS) program, "Evolution." Each unit uses an inquiry-based approach to meet the National Science Education Standards. Units include: (1) "What is the Nature of Science?"; (2) "Who Was Charles Darwin?"; (3) "What is the…

  8. Ecology, Elementary Teaching Guide.

    ERIC Educational Resources Information Center

    Gross, Iva Helen

    In an effort to provide background information and encourage incorporation of ecological understandings into the curriculum, this teacher's guide has been devised for fourth and fifth grade teachers. It utilizes an activity-oriented approach to discovery and inquiry, outlining behavioral objectives, learning activities, teaching suggestions, and…

  9. K-12 Art Guide.

    ERIC Educational Resources Information Center

    Furney, Trudy; And Others

    The development of students in various art fields is the focus of this K-12 art curriculum guide. The philosophy of the art program and the roles of administrator, teacher, and parent are outlined. The underlying school community relationships, and the objective, goals, and purposes of art education are described. Phases of child development in…

  10. Sampling. Teacher's Guide.

    ERIC Educational Resources Information Center

    San Francisco State Univ., CA.

    This document is the fourth of seven units developed by the Math Network Curriculum Project. Each unit, designed to be a 2-week module, is a teacher's guide which includes detailed directions along with the courseware and software needed. Teacher intervention in the non-computer activities that begin each unit is required, and the consistent use…

  11. SPACES. A Teacher's Guide.

    ERIC Educational Resources Information Center

    InterAmerica Research Associates, Rosslyn, VA.

    A variety of in-class assignments are included in this guide designed to accompany SPACES, a series of six, half-hour television programs designed to introduce students in the fourth through eighth grades to people and careers in science and technology. Targeted toward Black, Hispanic, Asian, and Native American minority children, the series…

  12. Accounting & Computing Curriculum Guide.

    ERIC Educational Resources Information Center

    Avani, Nathan T.; And Others

    This curriculum guide consists of materials for use in teaching a competency-based accounting and computing course that is designed to prepare students for employability in the following occupational areas: inventory control clerk, invoice clerk, payroll clerk, traffic clerk, general ledger bookkeeper, accounting clerk, account information clerk,…

  13. Masonry Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This masonry program guide presents the standard curriculum for technical institutes in Georgia. The curriculum addresses the minimum competencies for a masonry program. The general information section contains the following: purpose and objectives; program description, including admissions, typical job titles, and accreditation and certification;…

  14. Hospitality Occupations. Curriculum Guide.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Homemaking Education.

    This curriculum guide on the hospitality occupations was developed to help secondary and postsecondary home economics teachers prepare individuals for entry-level jobs in the hospitality industry. The content is in seven sections. The first section presents organizational charts of a medium-size hotel, food and beverage division, housekeeping and…

  15. Sensor Characteristics Reference Guide

    SciTech Connect

    Cree, Johnathan V.; Dansu, A.; Fuhr, P.; Lanzisera, Steven M.; McIntyre, T.; Muehleisen, Ralph T.; Starke, M.; Banerjee, Pranab; Kuruganti, T.; Castello, C.

    2013-04-01

    The Buildings Technologies Office (BTO), within the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy (EERE), is initiating a new program in Sensor and Controls. The vision of this program is: • Buildings operating automatically and continuously at peak energy efficiency over their lifetimes and interoperating effectively with the electric power grid. • Buildings that are self-configuring, self-commissioning, self-learning, self-diagnosing, self-healing, and self-transacting to enable continuous peak performance. • Lower overall building operating costs and higher asset valuation. The overarching goal is to capture 30% energy savings by enhanced management of energy consuming assets and systems through development of cost-effective sensors and controls. One step in achieving this vision is the publication of this Sensor Characteristics Reference Guide. The purpose of the guide is to inform building owners and operators of the current status, capabilities, and limitations of sensor technologies. It is hoped that this guide will aid in the design and procurement process and result in successful implementation of building sensor and control systems. DOE will also use this guide to identify research priorities, develop future specifications for potential market adoption, and provide market clarity through unbiased information

  16. LATIN--COURSE GUIDE.

    ERIC Educational Resources Information Center

    KENNEDY, DORA F.; AND OTHERS

    SECONDARY SCHOOL LATIN TEACHERS IN PRINCE GEORGE'S COUNTY, MARYLAND, COLLABORATED WITH THE FOREIGN LANGUAGE SUPERVISOR IN DEVELOPING THIS LATIN COURSE GUIDE DESIGNED TO ESTABLISH CLEARER PROGRAM OBJECTIVES, TO PRESENT BASIC CURRICULUM GUIDELINES FOR THREE LEVELS OF INSTRUCTION, AND TO ACT AS A SOURCE BOOK OF MATERIALS AND ACTIVITIES FOR PROGRAM…

  17. SOCMATICAS Teacher's Guide.

    ERIC Educational Resources Information Center

    Frame, Laurence

    Instructions for use of Socmaticas, a bilingual (Spanish-English), multicultural, multidisciplinary sports learning program are given in this teacher's guide. The program is based on the use of World Soccer team rosters (which include lists of players' names, ages, heights, weights, etc.) to teach English as a second language or Spanish. Students…

  18. Diffusion Strategy Guide.

    ERIC Educational Resources Information Center

    McCutcheon, James R.; Sanders, John R.

    A methodology is presented for planning and managing the spread of educational innovations. The first portion of the guide develops a theoretical framework for diffusion which summarizes and capitalizes on the latest marketing and on the latest marketing and diffusion research findings. Major stages in the diffusion paradigm discussed include…

  19. ADHD: A Teachers' Guide.

    ERIC Educational Resources Information Center

    Templeton, Rosalyn A.

    This paper provides a brief historical outline of attention deficit hyperactivity disorder (ADHD), its definition, its behavioral characteristics, and a guide to creating successful learning environments for these students. Diagnostic criteria for ADHD are listed and discussed, and incidence figures of 3 to 5 percent of all school-age children are…

  20. Beginner's guide to SPICE

    SciTech Connect

    Geisik, C.; Schilling, L.

    1988-07-01

    This work is intended to help a beginner learn the fundamentals of the circuit simulation program SPICE using a series of increasingly complex examples. These examples take the beginner from the most elementary circuits on up to an operational amplifier model. This work serves as a supplement to the existing SPICE documentation SPICE User's Guide. 13 figs.

  1. Management. Teacher's Instructional Guide.

    ERIC Educational Resources Information Center

    Hutnyak, Dana

    This teacher's instructional guide, which is part of a family and consumer sciences education series focusing on a broad range of employment opportunities, is intended to assist teachers responsible for teaching one- and two-year management programs for Texas high school students. The following are among the items included: (1) introductory…

  2. Plants Study Guide.

    ERIC Educational Resources Information Center

    Brynildson, Inga

    This study quide is intended to provide students with information about the types and functions of plants, along with some individual learning activities. The guide contains sections about: (1) the contributions of plants to life on earth and the benefits they afford to humanity; (2) the processes of photosynthesis and respiration; (3) the flow of…

  3. Mathematics Guide, K-12.

    ERIC Educational Resources Information Center

    Portales Public Schools, NM.

    This curriculum guide provides aid in organizing and planning for the mathematical needs of the individual classroom. It is recommended that: (1) each teacher study the entire curriculum to become familiar with the concepts that interlock and blend all the grades together, and (2) all students with average ability master 70% of the skills. The…

  4. Visible Traces. Teacher's Guide.

    ERIC Educational Resources Information Center

    ASIA Society, New York, NY.

    This teacher's guide is based on the exhibition, "Visible Traces: Rare Books and Special Collections from the National Library of China," a collaborative effort of the Queens Borough Public Library and the National Library of China; it links rare treasures from the National Library of China to curriculum standards. The following themes are…

  5. GLOBE Program Teacher's Guide.

    ERIC Educational Resources Information Center

    1997

    The GLOBE Program is a worldwide, hands-on educational program for elementary and secondary school students. GLOBE aims to increase student achievement in mathematics and science, awareness towards the environment, and improve science process skills through network technology. This teacher's guide provides an overview of the GLOBE program and…

  6. Health Occupations Cluster Guide.

    ERIC Educational Resources Information Center

    Oregon State Dept. of Education, Salem.

    Intended to assist the vocational teacher in designing and implementing a cluster program in health occupations, this guide suggests ideas for teaching the specific knowledge and skills that qualify students for entry-level employment in the health occupations field. The knowledge and skills are applicable to 12 occupations: dental assistant;…

  7. Migrant Education Administrative Guide.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Compensatory Education.

    Relating specifically to the North Carolina migrant education program's administrative responsibilities, this guide is designed to aid administrators in program management, monitoring project activities, project evaluation, self-assessment, determining needs for training and staff development, site-visit preparation, policy development, and…

  8. Communities, Teacher's Guide.

    ERIC Educational Resources Information Center

    California Univ., Berkeley. Science Curriculum Improvement Study.

    The Science Curriculum Improvement Study has developed this teacher's guide to "Communities," the fifth part of a six unit life science curriculum sequence. The six basic units, emphasizing organism-environment interactions, are organisms, life cycles, populations, environments, communities, and ecosystems, and make use of scientific and…

  9. Training Guide: Construction.

    ERIC Educational Resources Information Center

    Kogan Page, Ltd., London (England).

    This British guide is designed for training officers, employers, teachers, lecturers in architecture and related professional subjects, and others concerned with training and education in the construction industry. Chapter topics are: (1) the training picture (largely dealing with program planning and financial policy under the Construction…

  10. Training Guide: Road Transport.

    ERIC Educational Resources Information Center

    Kogan Page, Ltd., London (England).

    The third in a series of guides to British industrial training, this publication begins with a survey of training issues and tasks confronting the Road Transport Industry Training Board (RTITB). This is followed by information on RTITB policies and provisions; RTITB members, officers, and committees; apprenticeships and other training schemes;…

  11. Comp Curriculum Guide.

    ERIC Educational Resources Information Center

    Forsberg, Sara J.; And Others

    This curriculum guide describes and gives procedures for implementing the Comp Curriculum, which is composed of objectives categorized by age (birth to 5) and domains of developmental tasks (communication, self care, motor and problem solving), for handicapped and nonhandicapped children. (The objectives themselves are listed in a separate…

  12. Cosmetology. Secondary Curriculum Guide.

    ERIC Educational Resources Information Center

    Moye, Michael D.; And Others

    This curriculum guide is designed to offer guidelines along with supporting resources and teaching ideas from which the local secondary instructor can extract a cosmetology curriculum that meets local needs. Following an outline of the philosophy and goals underlying state and local vocational education programs in Georgia, the purpose and…

  13. Acronyms & Resource Guide

    ERIC Educational Resources Information Center

    Association of American Universities, 2011

    2011-01-01

    This guide includes the following: higher education and related associations; advocacy organizations and coalitions of interest to research universities; explanations of acronyms and terms commonly used in the university community; web links to government resources and agencies; Executive and Legislative Branch offices; and key federal…

  14. Fire Science Curriculum Guide.

    ERIC Educational Resources Information Center

    Oregon State Board of Education, Salem.

    This curriculum guide, developed in cooperation with the State Advisory Committee on Fireman Training for Post-High School Preparatory Programs, summarizes the need for formal training programs in fire protection and offers guidelines for their establishment. It is also a practical handbook for the planning of fire protection curriculums and…

  15. Employer Recruitment & Orientation Guide.

    ERIC Educational Resources Information Center

    Jobs for the Future, Boston, MA.

    Work-based learning is a competency-based experience that integrates classroom instruction with structured work site experiences. Its purpose is to allow students to gain occupational and employable skills while applying and advancing their academic abilities. This guide contains strategies and resources to help educators involve the business…

  16. Jackdaws Teacher's Guide.

    ERIC Educational Resources Information Center

    Greenberg, Judith E.; Carey, Helen H.

    This teacher's guide describes "Jackdaws"--materials that emphasize the use of primary and secondary sources in the teaching of history. A typical Jackdaws kit contains reproductions of primary and secondary source materials; broadsheets, which present detailed background information on the subject matter of the kit; and notes on the documents.…

  17. Dental Assisting Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide contains the standard dental assisting curriculum for technical institutes in Georgia. The curriculum encompasses the minimum competencies required for entry-level dental assistants, and includes job skills in the technical areas of preventive dentistry; four-handed dentistry; chairside assisting with emphasis in diagnostics,…

  18. Hydrodynamic blade guide

    DOEpatents

    Blaedel, Kenneth L.; Davis, Pete J.; Landram, Charles S.

    2000-01-01

    A saw having a self-pumped hydrodynamic blade guide or bearing for retaining the saw blade in a centered position in the saw kerf (width of cut made by the saw). The hydrodynamic blade guide or bearing utilizes pockets or grooves incorporated into the sides of the blade. The saw kerf in the workpiece provides the guide or bearing stator surface. Both sides of the blade entrain cutting fluid as the blade enters the kerf in the workpiece, and the trapped fluid provides pressure between the blade and the workpiece as an inverse function of the gap between the blade surface and the workpiece surface. If the blade wanders from the center of the kerf, then one gap will increase and one gap will decrease and the consequent pressure difference between the two sides of the blade will cause the blade to re-center itself in the kerf. Saws using the hydrodynamic blade guide or bearing have particular application in slicing slabs from boules of single crystal materials, for example, as well as for cutting other difficult to saw materials such as ceramics, glass, and brittle composite materials.

  19. ZOOMsci Activity Guide.

    ERIC Educational Resources Information Center

    Wade, Meredith

    This activity guide is based on the Public Broadcasting System's (PBS) program "ZOOM." It is designed for educators with activities that are categorized into three themes: (1) Things That Go, which includes "Air" which explores air pressure, "Rubber Bands" which discovers the potential energy of rubber bands, "Baking Soda and Vinegar" which…

  20. Russian Resource Materials Guide.

    ERIC Educational Resources Information Center

    Seymour, Viveca

    This guide provides the teacher of Russian with helpful background material and activities on the geography of the Soviet Union and the history of Russia as well as its customs, traditions, literary selections, songs, foods, and festivals. In addition to these topics, the introductory chapter outlines a philosophy for teaching and learning Russian…